Line Coverage for Module :
prim_reg_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T1 T2 T3
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T1 T2 T3
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T1 T2 T3
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T1 T2 T3
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T1 T2 T3
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T1 T2 T3
135 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Module :
prim_reg_cdc ( parameter DataWidth=2,ResetVal=0,BitMask=3,DstWrReq=0,TxnWidth=3 + DataWidth=32,ResetVal,BitMask,DstWrReq=0,TxnWidth=3 + DataWidth=8,ResetVal=4,BitMask=255,DstWrReq=0,TxnWidth=3 + DataWidth=16,ResetVal=155,BitMask=65535,DstWrReq=0,TxnWidth=3 + DataWidth=28,ResetVal=0,BitMask=268374015,DstWrReq=1,TxnWidth=3 + DataWidth=9,ResetVal=0,BitMask=511,DstWrReq=0,TxnWidth=3 + DataWidth=9,ResetVal=0,BitMask=511,DstWrReq=1,TxnWidth=3 + DataWidth=5,ResetVal=0,BitMask=31,DstWrReq=1,TxnWidth=3 )
Cond Coverage for Module self-instances :
| Total | Covered | Percent |
Conditions | 15 | 13 | 86.67 |
Logical | 15 | 13 | 86.67 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T8,T13,T14 |
1 | 0 | Covered | T1,T2,T3 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T1,T2,T3 |
1 | 1 | Covered | T1,T2,T3 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T1,T4,T5 |
1 | 0 | Covered | T1,T2,T3 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T1,T2,T3 |
1 | 1 | Covered | T1,T2,T3 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Not Covered | |
1 | 1 | Covered | T1,T4,T5 |
Cond Coverage for Module :
prim_reg_cdc ( parameter DataWidth=1,ResetVal=0,BitMask=1,DstWrReq=0,TxnWidth=3 )
Cond Coverage for Module self-instances :
| Total | Covered | Percent |
Conditions | 13 | 12 | 92.31 |
Logical | 13 | 12 | 92.31 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T15,T16,T17 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T15,T16,T17 |
1 | 1 | Covered | T15,T16,T17 |
LINE 123
EXPRESSION (src_wd_i & BitMask)
----1--- ---2---
-1- | -2- | Status | Tests |
0 | - | Covered | T15,T16,T17 |
1 | - | Covered | T16,T17,T18 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T15,T16,T17 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T15,T16,T17 |
1 | 1 | Covered | T15,T16,T17 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Module :
prim_reg_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T1,T2,T3 |
0 |
0 |
1 |
Covered |
T1,T2,T3 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T1,T2,T3 |
0 |
0 |
1 |
Covered |
T1,T2,T3 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Module :
prim_reg_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
158044187 |
0 |
0 |
T1 |
144532 |
17475 |
0 |
0 |
T2 |
195083 |
0 |
0 |
0 |
T3 |
3407 |
0 |
0 |
0 |
T4 |
99939 |
12696 |
0 |
0 |
T5 |
133093 |
16062 |
0 |
0 |
T6 |
150321 |
17083 |
0 |
0 |
T7 |
75991 |
10903 |
0 |
0 |
T8 |
2375818 |
43941 |
0 |
0 |
T9 |
8026096 |
7369 |
0 |
0 |
T10 |
1774736 |
14537 |
0 |
0 |
T11 |
14234816 |
105759 |
0 |
0 |
T12 |
9313024 |
9393 |
0 |
0 |
T13 |
0 |
21258 |
0 |
0 |
T14 |
0 |
100848 |
0 |
0 |
T15 |
575267 |
61957 |
0 |
0 |
T16 |
0 |
5668 |
0 |
0 |
T17 |
0 |
7532 |
0 |
0 |
T18 |
0 |
6429 |
0 |
0 |
T19 |
0 |
2225 |
0 |
0 |
T20 |
0 |
4077 |
0 |
0 |
T21 |
0 |
26188 |
0 |
0 |
T23 |
21276 |
0 |
0 |
0 |
T24 |
183988 |
0 |
0 |
0 |
T25 |
161168 |
0 |
0 |
0 |
T26 |
194752 |
0 |
0 |
0 |
T27 |
6200320 |
0 |
0 |
0 |
T28 |
3127472 |
0 |
0 |
0 |
T29 |
11951744 |
0 |
0 |
0 |
T40 |
0 |
959 |
0 |
0 |
T41 |
0 |
911 |
0 |
0 |
T42 |
541210 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
861333226 |
853196526 |
0 |
0 |
T1 |
30030 |
27924 |
0 |
0 |
T2 |
42250 |
650 |
0 |
0 |
T3 |
1924 |
416 |
0 |
0 |
T4 |
21606 |
20150 |
0 |
0 |
T5 |
30056 |
27612 |
0 |
0 |
T6 |
31226 |
28782 |
0 |
0 |
T7 |
18772 |
17342 |
0 |
0 |
T8 |
21424 |
12740 |
0 |
0 |
T23 |
2262 |
182 |
0 |
0 |
T24 |
39832 |
520 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
182279 |
0 |
0 |
T1 |
144532 |
41 |
0 |
0 |
T2 |
195083 |
0 |
0 |
0 |
T3 |
3407 |
0 |
0 |
0 |
T4 |
99939 |
31 |
0 |
0 |
T5 |
133093 |
41 |
0 |
0 |
T6 |
150321 |
41 |
0 |
0 |
T7 |
75991 |
29 |
0 |
0 |
T8 |
2375818 |
54 |
0 |
0 |
T9 |
8026096 |
29 |
0 |
0 |
T10 |
1774736 |
37 |
0 |
0 |
T11 |
14234816 |
62 |
0 |
0 |
T12 |
9313024 |
23 |
0 |
0 |
T13 |
0 |
32 |
0 |
0 |
T14 |
0 |
64 |
0 |
0 |
T15 |
575267 |
67 |
0 |
0 |
T16 |
0 |
18 |
0 |
0 |
T17 |
0 |
18 |
0 |
0 |
T18 |
0 |
18 |
0 |
0 |
T19 |
0 |
18 |
0 |
0 |
T20 |
0 |
54 |
0 |
0 |
T21 |
0 |
18 |
0 |
0 |
T23 |
21276 |
0 |
0 |
0 |
T24 |
183988 |
0 |
0 |
0 |
T25 |
161168 |
0 |
0 |
0 |
T26 |
194752 |
0 |
0 |
0 |
T27 |
6200320 |
0 |
0 |
0 |
T28 |
3127472 |
0 |
0 |
0 |
T29 |
11951744 |
0 |
0 |
0 |
T40 |
0 |
4 |
0 |
0 |
T41 |
0 |
2 |
0 |
0 |
T42 |
541210 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
3757832 |
3755986 |
0 |
0 |
T2 |
5072158 |
5032222 |
0 |
0 |
T3 |
88582 |
86372 |
0 |
0 |
T4 |
2598414 |
2596828 |
0 |
0 |
T5 |
3460418 |
3458130 |
0 |
0 |
T6 |
3908346 |
3905902 |
0 |
0 |
T7 |
1975766 |
1973868 |
0 |
0 |
T8 |
3633604 |
3590262 |
0 |
0 |
T23 |
553176 |
551408 |
0 |
0 |
T24 |
4783688 |
4744896 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_0_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 17 | 16 | 94.12 |
CONT_ASSIGN | 65 | 0 | 0 | |
ALWAYS | 71 | 5 | 4 | 80.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 7 | 7 | 100.00 |
CONT_ASSIGN | 150 | 0 | 0 | |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 unreachable assign src_req = src_we_i | src_re_i;
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 unreachable src_busy_q <= 1'b1;
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 0/1 ==> src_busy_q <= 1'b0;
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 unreachable src_q <= src_wd_i & BitMask;
124 unreachable txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T1 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T1 T4 T5
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 unreachable assign unused_wd = ^src_wd_i;
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_0_cdc
| Total | Covered | Percent |
Conditions | 7 | 6 | 85.71 |
Logical | 7 | 6 | 85.71 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Unreachable | |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Excluded | |
VC_COV_UNR |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T1,T4,T5 |
1 | 0 | Excluded | |
VC_COV_UNR |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Not Covered | |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Excluded | |
VC_COV_UNR |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Covered | T1,T4,T5 |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_0_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
6 |
5 |
83.33 |
IF |
71 |
3 |
2 |
66.67 |
IF |
115 |
3 |
3 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==> (Unreachable)
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Unreachable |
|
0 |
0 |
1 |
Not Covered |
|
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==> (Unreachable)
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Unreachable |
|
0 |
0 |
1 |
Covered |
T1,T4,T5 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_0_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_1_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 17 | 16 | 94.12 |
CONT_ASSIGN | 65 | 0 | 0 | |
ALWAYS | 71 | 5 | 4 | 80.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 7 | 7 | 100.00 |
CONT_ASSIGN | 150 | 0 | 0 | |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 unreachable assign src_req = src_we_i | src_re_i;
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 unreachable src_busy_q <= 1'b1;
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 0/1 ==> src_busy_q <= 1'b0;
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 unreachable src_q <= src_wd_i & BitMask;
124 unreachable txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T1 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T1 T4 T5
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 unreachable assign unused_wd = ^src_wd_i;
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_1_cdc
| Total | Covered | Percent |
Conditions | 7 | 6 | 85.71 |
Logical | 7 | 6 | 85.71 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Unreachable | |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Excluded | |
VC_COV_UNR |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T1,T4,T5 |
1 | 0 | Excluded | |
VC_COV_UNR |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Not Covered | |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Excluded | |
VC_COV_UNR |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Covered | T1,T4,T5 |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_1_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
6 |
5 |
83.33 |
IF |
71 |
3 |
2 |
66.67 |
IF |
115 |
3 |
3 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==> (Unreachable)
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Unreachable |
|
0 |
0 |
1 |
Not Covered |
|
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==> (Unreachable)
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Unreachable |
|
0 |
0 |
1 |
Covered |
T1,T4,T5 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_1_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_filter_status_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T13 T15 T16
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T13 T15 T16
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T13 T15 T16
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T13 T15 T16
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T13 T15 T16
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_filter_status_cdc
| Total | Covered | Percent |
Conditions | 14 | 12 | 85.71 |
Logical | 14 | 12 | 85.71 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T13,T15,T16 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T13,T15,T16 |
1 | 1 | Covered | T13,T15,T16 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T8,T13,T14 |
1 | 0 | Covered | T13,T15,T16 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T13,T15,T16 |
1 | 1 | Covered | T13,T15,T16 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Not Covered | |
1 | 1 | Covered | T8,T13,T14 |
Branch Coverage for Instance : tb.dut.u_reg.u_filter_status_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T13,T15,T16 |
0 |
0 |
1 |
Covered |
T13,T15,T16 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T13,T15,T16 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_filter_status_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
56839534 |
0 |
0 |
T13 |
164548 |
944 |
0 |
0 |
T14 |
578960 |
0 |
0 |
0 |
T15 |
575267 |
993 |
0 |
0 |
T16 |
370586 |
24658 |
0 |
0 |
T17 |
379180 |
33277 |
0 |
0 |
T18 |
324486 |
23626 |
0 |
0 |
T19 |
0 |
8751 |
0 |
0 |
T20 |
0 |
18520 |
0 |
0 |
T22 |
0 |
944 |
0 |
0 |
T40 |
0 |
32615 |
0 |
0 |
T41 |
0 |
36279 |
0 |
0 |
T42 |
541210 |
0 |
0 |
0 |
T43 |
83581 |
0 |
0 |
0 |
T44 |
117408 |
0 |
0 |
0 |
T45 |
12813 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
63085 |
0 |
0 |
T13 |
164548 |
1 |
0 |
0 |
T14 |
578960 |
0 |
0 |
0 |
T15 |
575267 |
1 |
0 |
0 |
T16 |
370586 |
64 |
0 |
0 |
T17 |
379180 |
94 |
0 |
0 |
T18 |
324486 |
70 |
0 |
0 |
T19 |
0 |
79 |
0 |
0 |
T20 |
0 |
210 |
0 |
0 |
T22 |
0 |
2 |
0 |
0 |
T40 |
0 |
143 |
0 |
0 |
T41 |
0 |
80 |
0 |
0 |
T42 |
541210 |
0 |
0 |
0 |
T43 |
83581 |
0 |
0 |
0 |
T44 |
117408 |
0 |
0 |
0 |
T45 |
12813 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_fsm_state_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 21 | 21 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 0 | 0 | |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T1 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T1 T4 T5
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 unreachable assign unused_wd = ^src_wd_i;
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_fsm_state_cdc
| Total | Covered | Percent |
Conditions | 14 | 12 | 85.71 |
Logical | 14 | 12 | 85.71 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T8,T13,T14 |
1 | 0 | Unreachable | |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T1,T4,T5 |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Not Covered | |
1 | 1 | Covered | T1,T4,T5 |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_fsm_state_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T1,T4,T5 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_fsm_state_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
98459 |
0 |
0 |
T8 |
139754 |
1082 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1283 |
0 |
0 |
T14 |
0 |
1926 |
0 |
0 |
T15 |
0 |
1292 |
0 |
0 |
T22 |
0 |
792 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
T30 |
0 |
830 |
0 |
0 |
T31 |
0 |
988 |
0 |
0 |
T32 |
0 |
1394 |
0 |
0 |
T46 |
0 |
1582 |
0 |
0 |
T47 |
0 |
1374 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
89 |
0 |
0 |
T8 |
139754 |
1 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
1 |
0 |
0 |
T15 |
0 |
1 |
0 |
0 |
T22 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
T30 |
0 |
1 |
0 |
0 |
T31 |
0 |
2 |
0 |
0 |
T32 |
0 |
1 |
0 |
0 |
T46 |
0 |
1 |
0 |
0 |
T47 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_en_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T1 T4 T5
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T1 T4 T5
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T1 T4 T5
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T1 T4 T5
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T1 T4 T5
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T1 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T1 T4 T5
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_en_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T1,T4,T5 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T1,T4,T5 |
1 | 1 | Covered | T1,T4,T5 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T1,T4,T5 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T1,T4,T5 |
1 | 1 | Covered | T1,T4,T5 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_en_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T1,T4,T5 |
0 |
0 |
1 |
Covered |
T1,T4,T5 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T1,T4,T5 |
0 |
0 |
1 |
Covered |
T1,T4,T5 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_en_ctl_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
26662268 |
0 |
0 |
T1 |
144532 |
17475 |
0 |
0 |
T2 |
195083 |
0 |
0 |
0 |
T3 |
3407 |
0 |
0 |
0 |
T4 |
99939 |
12696 |
0 |
0 |
T5 |
133093 |
16062 |
0 |
0 |
T6 |
150321 |
17083 |
0 |
0 |
T7 |
75991 |
10903 |
0 |
0 |
T8 |
139754 |
4225 |
0 |
0 |
T9 |
0 |
7369 |
0 |
0 |
T10 |
0 |
14537 |
0 |
0 |
T11 |
0 |
105759 |
0 |
0 |
T12 |
0 |
9393 |
0 |
0 |
T23 |
21276 |
0 |
0 |
0 |
T24 |
183988 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
31697 |
0 |
0 |
T1 |
144532 |
41 |
0 |
0 |
T2 |
195083 |
0 |
0 |
0 |
T3 |
3407 |
0 |
0 |
0 |
T4 |
99939 |
31 |
0 |
0 |
T5 |
133093 |
41 |
0 |
0 |
T6 |
150321 |
41 |
0 |
0 |
T7 |
75991 |
29 |
0 |
0 |
T8 |
139754 |
6 |
0 |
0 |
T9 |
0 |
29 |
0 |
0 |
T10 |
0 |
37 |
0 |
0 |
T11 |
0 |
62 |
0 |
0 |
T12 |
0 |
23 |
0 |
0 |
T23 |
21276 |
0 |
0 |
0 |
T24 |
183988 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_pd_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T1 T4 T5
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T1 T4 T5
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T1 T4 T5
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T1 T4 T5
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T1 T4 T5
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T1 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T1 T4 T5
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_pd_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T1,T4,T5 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T1,T4,T5 |
1 | 1 | Covered | T1,T4,T5 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T1,T4,T5 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T1,T4,T5 |
1 | 1 | Covered | T1,T4,T5 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_pd_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T1,T4,T5 |
0 |
0 |
1 |
Covered |
T1,T4,T5 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T1,T4,T5 |
0 |
0 |
1 |
Covered |
T1,T4,T5 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_pd_ctl_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
12579260 |
0 |
0 |
T1 |
144532 |
371 |
0 |
0 |
T2 |
195083 |
0 |
0 |
0 |
T3 |
3407 |
0 |
0 |
0 |
T4 |
99939 |
5854 |
0 |
0 |
T5 |
133093 |
341 |
0 |
0 |
T6 |
150321 |
350 |
0 |
0 |
T7 |
75991 |
5230 |
0 |
0 |
T8 |
139754 |
3681 |
0 |
0 |
T9 |
0 |
3507 |
0 |
0 |
T10 |
0 |
6858 |
0 |
0 |
T11 |
0 |
17848 |
0 |
0 |
T12 |
0 |
4560 |
0 |
0 |
T23 |
21276 |
0 |
0 |
0 |
T24 |
183988 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
15316 |
0 |
0 |
T1 |
144532 |
1 |
0 |
0 |
T2 |
195083 |
0 |
0 |
0 |
T3 |
3407 |
0 |
0 |
0 |
T4 |
99939 |
15 |
0 |
0 |
T5 |
133093 |
1 |
0 |
0 |
T6 |
150321 |
1 |
0 |
0 |
T7 |
75991 |
14 |
0 |
0 |
T8 |
139754 |
6 |
0 |
0 |
T9 |
0 |
14 |
0 |
0 |
T10 |
0 |
18 |
0 |
0 |
T11 |
0 |
11 |
0 |
0 |
T12 |
0 |
11 |
0 |
0 |
T23 |
21276 |
0 |
0 |
0 |
T24 |
183988 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_lp_sample_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T2 T3 T23
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T2 T3 T23
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T2 T3 T23
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T2 T3 T23
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T2 T3 T23
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T2 T3 T23
135 1/1 txn_bits_q <= '0;
Tests: T2 T3 T23
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_lp_sample_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T2,T3,T23 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T2,T3,T23 |
1 | 1 | Covered | T2,T3,T23 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T2,T3,T23 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T2,T3,T23 |
1 | 1 | Covered | T2,T3,T23 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_lp_sample_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T2,T3,T23 |
0 |
0 |
1 |
Covered |
T2,T3,T23 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T2,T3,T23 |
0 |
0 |
1 |
Covered |
T2,T3,T23 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_lp_sample_ctl_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
10207574 |
0 |
0 |
T2 |
195083 |
358 |
0 |
0 |
T3 |
3407 |
133 |
0 |
0 |
T4 |
99939 |
0 |
0 |
0 |
T5 |
133093 |
0 |
0 |
0 |
T6 |
150321 |
0 |
0 |
0 |
T7 |
75991 |
0 |
0 |
0 |
T8 |
139754 |
2815 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T23 |
21276 |
724 |
0 |
0 |
T24 |
183988 |
464 |
0 |
0 |
T25 |
0 |
248 |
0 |
0 |
T26 |
0 |
450 |
0 |
0 |
T27 |
0 |
733 |
0 |
0 |
T29 |
0 |
1916 |
0 |
0 |
T48 |
0 |
751 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
12475 |
0 |
0 |
T2 |
195083 |
1 |
0 |
0 |
T3 |
3407 |
1 |
0 |
0 |
T4 |
99939 |
0 |
0 |
0 |
T5 |
133093 |
0 |
0 |
0 |
T6 |
150321 |
0 |
0 |
0 |
T7 |
75991 |
0 |
0 |
0 |
T8 |
139754 |
4 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T23 |
21276 |
1 |
0 |
0 |
T24 |
183988 |
1 |
0 |
0 |
T25 |
0 |
1 |
0 |
0 |
T26 |
0 |
1 |
0 |
0 |
T27 |
0 |
1 |
0 |
0 |
T29 |
0 |
1 |
0 |
0 |
T48 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_sample_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T2 T3 T23
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T2 T3 T23
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T2 T3 T23
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T2 T3 T23
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T2 T3 T23
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T2 T3 T23
135 1/1 txn_bits_q <= '0;
Tests: T2 T3 T23
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_sample_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T2,T3,T23 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T2,T3,T23 |
1 | 1 | Covered | T2,T3,T23 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T2,T3,T23 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T2,T3,T23 |
1 | 1 | Covered | T2,T3,T23 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_sample_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T2,T3,T23 |
0 |
0 |
1 |
Covered |
T2,T3,T23 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T2,T3,T23 |
0 |
0 |
1 |
Covered |
T2,T3,T23 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_sample_ctl_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
10298185 |
0 |
0 |
T2 |
195083 |
360 |
0 |
0 |
T3 |
3407 |
100 |
0 |
0 |
T4 |
99939 |
0 |
0 |
0 |
T5 |
133093 |
0 |
0 |
0 |
T6 |
150321 |
0 |
0 |
0 |
T7 |
75991 |
0 |
0 |
0 |
T8 |
139754 |
2846 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T23 |
21276 |
733 |
0 |
0 |
T24 |
183988 |
476 |
0 |
0 |
T25 |
0 |
257 |
0 |
0 |
T26 |
0 |
464 |
0 |
0 |
T27 |
0 |
735 |
0 |
0 |
T29 |
0 |
1920 |
0 |
0 |
T48 |
0 |
759 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
12485 |
0 |
0 |
T2 |
195083 |
1 |
0 |
0 |
T3 |
3407 |
1 |
0 |
0 |
T4 |
99939 |
0 |
0 |
0 |
T5 |
133093 |
0 |
0 |
0 |
T6 |
150321 |
0 |
0 |
0 |
T7 |
75991 |
0 |
0 |
0 |
T8 |
139754 |
4 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T23 |
21276 |
1 |
0 |
0 |
T24 |
183988 |
1 |
0 |
0 |
T25 |
0 |
1 |
0 |
0 |
T26 |
0 |
1 |
0 |
0 |
T27 |
0 |
1 |
0 |
0 |
T29 |
0 |
1 |
0 |
0 |
T48 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_0_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_0_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_0_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_0_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1704927 |
0 |
0 |
T8 |
139754 |
2709 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1455 |
0 |
0 |
T14 |
0 |
6363 |
0 |
0 |
T15 |
0 |
4744 |
0 |
0 |
T16 |
0 |
328 |
0 |
0 |
T17 |
0 |
455 |
0 |
0 |
T18 |
0 |
385 |
0 |
0 |
T19 |
0 |
122 |
0 |
0 |
T20 |
0 |
245 |
0 |
0 |
T21 |
0 |
1468 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1862 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
5 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_1_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_1_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_1_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_1_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1586012 |
0 |
0 |
T8 |
139754 |
2687 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1432 |
0 |
0 |
T14 |
0 |
6355 |
0 |
0 |
T15 |
0 |
3737 |
0 |
0 |
T16 |
0 |
326 |
0 |
0 |
T17 |
0 |
441 |
0 |
0 |
T18 |
0 |
378 |
0 |
0 |
T19 |
0 |
117 |
0 |
0 |
T20 |
0 |
239 |
0 |
0 |
T21 |
0 |
1466 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1730 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_2_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_2_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_2_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_2_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1624520 |
0 |
0 |
T8 |
139754 |
2650 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1414 |
0 |
0 |
T14 |
0 |
6347 |
0 |
0 |
T15 |
0 |
3729 |
0 |
0 |
T16 |
0 |
324 |
0 |
0 |
T17 |
0 |
430 |
0 |
0 |
T18 |
0 |
374 |
0 |
0 |
T19 |
0 |
135 |
0 |
0 |
T20 |
0 |
233 |
0 |
0 |
T21 |
0 |
1464 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1764 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_3_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_3_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_3_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_3_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1604582 |
0 |
0 |
T8 |
139754 |
2632 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1400 |
0 |
0 |
T14 |
0 |
6339 |
0 |
0 |
T15 |
0 |
3721 |
0 |
0 |
T16 |
0 |
322 |
0 |
0 |
T17 |
0 |
415 |
0 |
0 |
T18 |
0 |
369 |
0 |
0 |
T19 |
0 |
119 |
0 |
0 |
T20 |
0 |
227 |
0 |
0 |
T21 |
0 |
1462 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1768 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_4_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_4_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_4_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_4_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1588310 |
0 |
0 |
T8 |
139754 |
2591 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1387 |
0 |
0 |
T14 |
0 |
6331 |
0 |
0 |
T15 |
0 |
3713 |
0 |
0 |
T16 |
0 |
320 |
0 |
0 |
T17 |
0 |
404 |
0 |
0 |
T18 |
0 |
359 |
0 |
0 |
T19 |
0 |
112 |
0 |
0 |
T20 |
0 |
221 |
0 |
0 |
T21 |
0 |
1460 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1750 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_5_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_5_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_5_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_5_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1627596 |
0 |
0 |
T8 |
139754 |
2552 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1367 |
0 |
0 |
T14 |
0 |
6323 |
0 |
0 |
T15 |
0 |
3705 |
0 |
0 |
T16 |
0 |
318 |
0 |
0 |
T17 |
0 |
395 |
0 |
0 |
T18 |
0 |
351 |
0 |
0 |
T19 |
0 |
134 |
0 |
0 |
T20 |
0 |
215 |
0 |
0 |
T21 |
0 |
1458 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1781 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_6_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_6_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_6_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_6_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1564963 |
0 |
0 |
T8 |
139754 |
2525 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1351 |
0 |
0 |
T14 |
0 |
6315 |
0 |
0 |
T15 |
0 |
3697 |
0 |
0 |
T16 |
0 |
316 |
0 |
0 |
T17 |
0 |
384 |
0 |
0 |
T18 |
0 |
341 |
0 |
0 |
T19 |
0 |
127 |
0 |
0 |
T20 |
0 |
209 |
0 |
0 |
T21 |
0 |
1456 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1753 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_7_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_7_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_7_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn0_filter_ctl_7_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1582967 |
0 |
0 |
T8 |
139754 |
2490 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1336 |
0 |
0 |
T14 |
0 |
6307 |
0 |
0 |
T15 |
0 |
3689 |
0 |
0 |
T16 |
0 |
314 |
0 |
0 |
T17 |
0 |
372 |
0 |
0 |
T18 |
0 |
338 |
0 |
0 |
T19 |
0 |
117 |
0 |
0 |
T20 |
0 |
203 |
0 |
0 |
T21 |
0 |
1454 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1770 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_0_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_0_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_0_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_0_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1669055 |
0 |
0 |
T8 |
139754 |
2455 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1326 |
0 |
0 |
T14 |
0 |
6299 |
0 |
0 |
T15 |
0 |
4678 |
0 |
0 |
T16 |
0 |
312 |
0 |
0 |
T17 |
0 |
359 |
0 |
0 |
T18 |
0 |
326 |
0 |
0 |
T19 |
0 |
113 |
0 |
0 |
T20 |
0 |
197 |
0 |
0 |
T21 |
0 |
1452 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1847 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
5 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_1_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_1_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_1_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_1_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1589478 |
0 |
0 |
T8 |
139754 |
2437 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1306 |
0 |
0 |
T14 |
0 |
6291 |
0 |
0 |
T15 |
0 |
3673 |
0 |
0 |
T16 |
0 |
310 |
0 |
0 |
T17 |
0 |
349 |
0 |
0 |
T18 |
0 |
323 |
0 |
0 |
T19 |
0 |
139 |
0 |
0 |
T20 |
0 |
191 |
0 |
0 |
T21 |
0 |
1450 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1775 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_2_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_2_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_2_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_2_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1542874 |
0 |
0 |
T8 |
139754 |
2409 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1286 |
0 |
0 |
T14 |
0 |
6283 |
0 |
0 |
T15 |
0 |
3665 |
0 |
0 |
T16 |
0 |
308 |
0 |
0 |
T17 |
0 |
458 |
0 |
0 |
T18 |
0 |
314 |
0 |
0 |
T19 |
0 |
129 |
0 |
0 |
T20 |
0 |
185 |
0 |
0 |
T21 |
0 |
1448 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1739 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_3_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_3_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_3_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_3_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1588090 |
0 |
0 |
T8 |
139754 |
2380 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1267 |
0 |
0 |
T14 |
0 |
6275 |
0 |
0 |
T15 |
0 |
3657 |
0 |
0 |
T16 |
0 |
306 |
0 |
0 |
T17 |
0 |
451 |
0 |
0 |
T18 |
0 |
312 |
0 |
0 |
T19 |
0 |
121 |
0 |
0 |
T20 |
0 |
254 |
0 |
0 |
T21 |
0 |
1446 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1764 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_4_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_4_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_4_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_4_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1584870 |
0 |
0 |
T8 |
139754 |
2352 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1256 |
0 |
0 |
T14 |
0 |
6267 |
0 |
0 |
T15 |
0 |
3649 |
0 |
0 |
T16 |
0 |
304 |
0 |
0 |
T17 |
0 |
448 |
0 |
0 |
T18 |
0 |
304 |
0 |
0 |
T19 |
0 |
113 |
0 |
0 |
T20 |
0 |
248 |
0 |
0 |
T21 |
0 |
1444 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1766 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_5_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_5_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_5_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_5_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1633787 |
0 |
0 |
T8 |
139754 |
2316 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1246 |
0 |
0 |
T14 |
0 |
6259 |
0 |
0 |
T15 |
0 |
3641 |
0 |
0 |
T16 |
0 |
302 |
0 |
0 |
T17 |
0 |
429 |
0 |
0 |
T18 |
0 |
393 |
0 |
0 |
T19 |
0 |
137 |
0 |
0 |
T20 |
0 |
242 |
0 |
0 |
T21 |
0 |
1442 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1796 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_6_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_6_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_6_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_6_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1565321 |
0 |
0 |
T8 |
139754 |
2278 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1222 |
0 |
0 |
T14 |
0 |
6251 |
0 |
0 |
T15 |
0 |
3633 |
0 |
0 |
T16 |
0 |
300 |
0 |
0 |
T17 |
0 |
416 |
0 |
0 |
T18 |
0 |
389 |
0 |
0 |
T19 |
0 |
126 |
0 |
0 |
T20 |
0 |
236 |
0 |
0 |
T21 |
0 |
1440 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1773 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_7_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_7_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_7_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_chn1_filter_ctl_7_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1536618 |
0 |
0 |
T8 |
139754 |
2253 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1207 |
0 |
0 |
T14 |
0 |
6243 |
0 |
0 |
T15 |
0 |
3625 |
0 |
0 |
T16 |
0 |
298 |
0 |
0 |
T17 |
0 |
413 |
0 |
0 |
T18 |
0 |
381 |
0 |
0 |
T19 |
0 |
123 |
0 |
0 |
T20 |
0 |
230 |
0 |
0 |
T21 |
0 |
1438 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1759 |
0 |
0 |
T8 |
139754 |
3 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
4 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T20 |
0 |
3 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_wakeup_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T8 T13 T14
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T8 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T8 T13 T14
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T8 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T8 T13 T14
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T8 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T8 T13 T14
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_wakeup_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T8,T13,T14 |
1 | 1 | Covered | T8,T13,T14 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_wakeup_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T8,T13,T14 |
0 |
0 |
1 |
Covered |
T8,T13,T14 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_wakeup_ctl_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1095851 |
0 |
0 |
T8 |
139754 |
784 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
562 |
0 |
0 |
T14 |
0 |
2868 |
0 |
0 |
T15 |
0 |
961 |
0 |
0 |
T21 |
0 |
1430 |
0 |
0 |
T22 |
0 |
761 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
T40 |
0 |
497 |
0 |
0 |
T49 |
0 |
574 |
0 |
0 |
T50 |
0 |
481 |
0 |
0 |
T51 |
0 |
245 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1264 |
0 |
0 |
T8 |
139754 |
1 |
0 |
0 |
T9 |
501631 |
0 |
0 |
0 |
T10 |
110921 |
0 |
0 |
0 |
T11 |
889676 |
0 |
0 |
0 |
T12 |
582064 |
0 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
2 |
0 |
0 |
T15 |
0 |
1 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T22 |
0 |
2 |
0 |
0 |
T25 |
10073 |
0 |
0 |
0 |
T26 |
12172 |
0 |
0 |
0 |
T27 |
387520 |
0 |
0 |
0 |
T28 |
195467 |
0 |
0 |
0 |
T29 |
746984 |
0 |
0 |
0 |
T40 |
0 |
2 |
0 |
0 |
T49 |
0 |
3 |
0 |
0 |
T50 |
0 |
1 |
0 |
0 |
T51 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_fsm_rst_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T15 T16 T17
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T15 T16 T17
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T15 T16 T17
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T15 T16 T17
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T15 T16 T17
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T15 T16 T17
135 1/1 txn_bits_q <= '0;
Tests: T15 T16 T17
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_fsm_rst_cdc
| Total | Covered | Percent |
Conditions | 13 | 12 | 92.31 |
Logical | 13 | 12 | 92.31 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T15,T16,T17 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T15,T16,T17 |
1 | 1 | Covered | T15,T16,T17 |
LINE 123
EXPRESSION (src_wd_i & BitMask)
----1--- ---2---
-1- | -2- | Status | Tests |
0 | - | Covered | T15,T16,T17 |
1 | - | Covered | T16,T17,T18 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T15,T16,T17 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T15,T16,T17 |
1 | 1 | Covered | T15,T16,T17 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_fsm_rst_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T15,T16,T17 |
0 |
0 |
1 |
Covered |
T15,T16,T17 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T15,T16,T17 |
0 |
0 |
1 |
Covered |
T15,T16,T17 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
Assert Coverage for Instance : tb.dut.u_reg.u_adc_fsm_rst_cdc
Assertion Details
BusySrcReqChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
14669086 |
0 |
0 |
T15 |
575267 |
1001 |
0 |
0 |
T16 |
370586 |
660 |
0 |
0 |
T17 |
379180 |
913 |
0 |
0 |
T18 |
324486 |
792 |
0 |
0 |
T19 |
114034 |
241 |
0 |
0 |
T20 |
249575 |
502 |
0 |
0 |
T21 |
0 |
2940 |
0 |
0 |
T40 |
0 |
959 |
0 |
0 |
T41 |
0 |
911 |
0 |
0 |
T42 |
541210 |
0 |
0 |
0 |
T43 |
83581 |
0 |
0 |
0 |
T44 |
117408 |
0 |
0 |
0 |
T45 |
12813 |
0 |
0 |
0 |
T49 |
0 |
1660 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
33128201 |
32815251 |
0 |
0 |
T1 |
1155 |
1074 |
0 |
0 |
T2 |
1625 |
25 |
0 |
0 |
T3 |
74 |
16 |
0 |
0 |
T4 |
831 |
775 |
0 |
0 |
T5 |
1156 |
1062 |
0 |
0 |
T6 |
1201 |
1107 |
0 |
0 |
T7 |
722 |
667 |
0 |
0 |
T8 |
824 |
490 |
0 |
0 |
T23 |
87 |
7 |
0 |
0 |
T24 |
1532 |
20 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
17471 |
0 |
0 |
T15 |
575267 |
1 |
0 |
0 |
T16 |
370586 |
2 |
0 |
0 |
T17 |
379180 |
2 |
0 |
0 |
T18 |
324486 |
2 |
0 |
0 |
T19 |
114034 |
2 |
0 |
0 |
T20 |
249575 |
6 |
0 |
0 |
T21 |
0 |
2 |
0 |
0 |
T40 |
0 |
4 |
0 |
0 |
T41 |
0 |
2 |
0 |
0 |
T42 |
541210 |
0 |
0 |
0 |
T43 |
83581 |
0 |
0 |
0 |
T44 |
117408 |
0 |
0 |
0 |
T45 |
12813 |
0 |
0 |
0 |
T49 |
0 |
6 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
144532 |
144461 |
0 |
0 |
T2 |
195083 |
193547 |
0 |
0 |
T3 |
3407 |
3322 |
0 |
0 |
T4 |
99939 |
99878 |
0 |
0 |
T5 |
133093 |
133005 |
0 |
0 |
T6 |
150321 |
150227 |
0 |
0 |
T7 |
75991 |
75918 |
0 |
0 |
T8 |
139754 |
138087 |
0 |
0 |
T23 |
21276 |
21208 |
0 |
0 |
T24 |
183988 |
182496 |
0 |
0 |