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 | T5,T12,T13 |
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 | T3,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 | T3,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 | T14,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 | T14,T16,T17 |
1 | 1 | Covered | T14,T16,T17 |
LINE 123
EXPRESSION (src_wd_i & BitMask)
----1--- ---2---
-1- | -2- | Status | Tests |
0 | - | Covered | T14,T16,T17 |
1 | - | Covered | T14,T16,T17 |
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 | T14,T16,T17 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T14,T16,T17 |
1 | 1 | Covered | T14,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 |
162095736 |
0 |
0 |
T3 |
61034 |
7201 |
0 |
0 |
T4 |
389037 |
48383 |
0 |
0 |
T5 |
4175829 |
29484 |
0 |
0 |
T6 |
4313716 |
35489 |
0 |
0 |
T7 |
1380876 |
10068 |
0 |
0 |
T8 |
8940895 |
67780 |
0 |
0 |
T9 |
4942903 |
34389 |
0 |
0 |
T10 |
1366069 |
10620 |
0 |
0 |
T11 |
11200400 |
10425 |
0 |
0 |
T12 |
0 |
36266 |
0 |
0 |
T13 |
0 |
28398 |
0 |
0 |
T14 |
595340 |
22281 |
0 |
0 |
T15 |
560305 |
48848 |
0 |
0 |
T16 |
133794 |
1804 |
0 |
0 |
T17 |
0 |
8032 |
0 |
0 |
T18 |
0 |
6422 |
0 |
0 |
T19 |
0 |
8098 |
0 |
0 |
T20 |
0 |
710 |
0 |
0 |
T21 |
0 |
475 |
0 |
0 |
T22 |
3211 |
0 |
0 |
0 |
T23 |
526745 |
0 |
0 |
0 |
T31 |
0 |
28837 |
0 |
0 |
T41 |
0 |
1031 |
0 |
0 |
T42 |
6789248 |
0 |
0 |
0 |
T43 |
665104 |
0 |
0 |
0 |
T44 |
758199 |
0 |
0 |
0 |
T45 |
542784 |
0 |
0 |
0 |
T46 |
821899 |
0 |
0 |
0 |
T47 |
341689 |
0 |
0 |
0 |
T48 |
231870 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
843152336 |
835437876 |
0 |
0 |
T1 |
2106 |
104 |
0 |
0 |
T2 |
20020 |
416 |
0 |
0 |
T3 |
31694 |
30394 |
0 |
0 |
T4 |
20826 |
18408 |
0 |
0 |
T5 |
13260 |
4732 |
0 |
0 |
T6 |
27430 |
25922 |
0 |
0 |
T7 |
17550 |
15600 |
0 |
0 |
T8 |
28730 |
27352 |
0 |
0 |
T22 |
2756 |
780 |
0 |
0 |
T23 |
1638 |
130 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
181903 |
0 |
0 |
T3 |
61034 |
41 |
0 |
0 |
T4 |
389037 |
29 |
0 |
0 |
T5 |
4175829 |
20 |
0 |
0 |
T6 |
4313716 |
41 |
0 |
0 |
T7 |
1380876 |
25 |
0 |
0 |
T8 |
8940895 |
41 |
0 |
0 |
T9 |
4942903 |
41 |
0 |
0 |
T10 |
1366069 |
41 |
0 |
0 |
T11 |
11200400 |
33 |
0 |
0 |
T12 |
0 |
142 |
0 |
0 |
T13 |
0 |
34 |
0 |
0 |
T14 |
595340 |
58 |
0 |
0 |
T15 |
560305 |
64 |
0 |
0 |
T16 |
133794 |
18 |
0 |
0 |
T17 |
0 |
18 |
0 |
0 |
T18 |
0 |
36 |
0 |
0 |
T19 |
0 |
18 |
0 |
0 |
T20 |
0 |
2 |
0 |
0 |
T21 |
0 |
2 |
0 |
0 |
T22 |
3211 |
0 |
0 |
0 |
T23 |
526745 |
0 |
0 |
0 |
T31 |
0 |
16 |
0 |
0 |
T41 |
0 |
4 |
0 |
0 |
T42 |
6789248 |
0 |
0 |
0 |
T43 |
665104 |
0 |
0 |
0 |
T44 |
758199 |
0 |
0 |
0 |
T45 |
542784 |
0 |
0 |
0 |
T46 |
821899 |
0 |
0 |
0 |
T47 |
341689 |
0 |
0 |
0 |
T48 |
231870 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
1081028 |
1079572 |
0 |
0 |
T2 |
2404974 |
2381938 |
0 |
0 |
T3 |
1586884 |
1585168 |
0 |
0 |
T4 |
10114962 |
10112570 |
0 |
0 |
T5 |
6386562 |
6312956 |
0 |
0 |
T6 |
6597448 |
6596148 |
0 |
0 |
T7 |
2111928 |
2109458 |
0 |
0 |
T8 |
13674310 |
13671996 |
0 |
0 |
T22 |
83486 |
81120 |
0 |
0 |
T23 |
805610 |
803894 |
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: T3 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T3 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 | T3,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 | T3,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 |
T3,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 |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
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 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T3 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T3 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 | T3,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 | T3,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 |
T3,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 |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
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 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T12 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: T12 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T12 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: T12 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T12 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: T12 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T12 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 | T12,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 | T12,T13,T14 |
1 | 1 | Covered | T12,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 | T12,T13,T14 |
1 | 0 | Covered | T12,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T12,T13,T14 |
1 | 1 | Covered | T12,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 | T12,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 |
T12,T13,T14 |
0 |
0 |
1 |
Covered |
T12,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 |
T12,T13,T14 |
0 |
0 |
1 |
Covered |
T12,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 |
62855100 |
0 |
0 |
T12 |
485034 |
969 |
0 |
0 |
T13 |
393091 |
1905 |
0 |
0 |
T14 |
595340 |
1220 |
0 |
0 |
T15 |
0 |
2377 |
0 |
0 |
T16 |
0 |
7616 |
0 |
0 |
T17 |
0 |
30508 |
0 |
0 |
T18 |
0 |
24685 |
0 |
0 |
T19 |
0 |
32950 |
0 |
0 |
T20 |
0 |
17567 |
0 |
0 |
T21 |
0 |
16676 |
0 |
0 |
T24 |
148498 |
0 |
0 |
0 |
T25 |
174668 |
0 |
0 |
0 |
T26 |
821468 |
0 |
0 |
0 |
T27 |
583962 |
0 |
0 |
0 |
T28 |
18603 |
0 |
0 |
0 |
T29 |
412987 |
0 |
0 |
0 |
T30 |
959815 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
64624 |
0 |
0 |
T12 |
485034 |
4 |
0 |
0 |
T13 |
393091 |
2 |
0 |
0 |
T14 |
595340 |
3 |
0 |
0 |
T15 |
0 |
3 |
0 |
0 |
T16 |
0 |
62 |
0 |
0 |
T17 |
0 |
74 |
0 |
0 |
T18 |
0 |
162 |
0 |
0 |
T19 |
0 |
78 |
0 |
0 |
T20 |
0 |
66 |
0 |
0 |
T21 |
0 |
81 |
0 |
0 |
T24 |
148498 |
0 |
0 |
0 |
T25 |
174668 |
0 |
0 |
0 |
T26 |
821468 |
0 |
0 |
0 |
T27 |
583962 |
0 |
0 |
0 |
T28 |
18603 |
0 |
0 |
0 |
T29 |
412987 |
0 |
0 |
0 |
T30 |
959815 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T3 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T3 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 | T5,T12,T13 |
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 | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T3,T4,T5 |
1 | 0 | Covered | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T3,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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T3,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 |
87494 |
0 |
0 |
T5 |
245637 |
1290 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
1176 |
0 |
0 |
T13 |
0 |
929 |
0 |
0 |
T14 |
0 |
1489 |
0 |
0 |
T15 |
0 |
854 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
2796 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
T49 |
0 |
954 |
0 |
0 |
T50 |
0 |
791 |
0 |
0 |
T51 |
0 |
965 |
0 |
0 |
T52 |
0 |
1009 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
88 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
2 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
1 |
0 |
0 |
T15 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
T49 |
0 |
1 |
0 |
0 |
T50 |
0 |
1 |
0 |
0 |
T51 |
0 |
1 |
0 |
0 |
T52 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T3 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: T3 T4 T5
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T3 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: T3 T4 T5
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T3 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: T3 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T3 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 | T3,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 | T3,T4,T5 |
1 | 1 | Covered | T3,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 | T3,T4,T5 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T3,T4,T5 |
1 | 1 | Covered | T3,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 |
T3,T4,T5 |
0 |
0 |
1 |
Covered |
T3,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 |
T3,T4,T5 |
0 |
0 |
1 |
Covered |
T3,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 |
26065858 |
0 |
0 |
T3 |
61034 |
7201 |
0 |
0 |
T4 |
389037 |
48383 |
0 |
0 |
T5 |
245637 |
6716 |
0 |
0 |
T6 |
253748 |
35489 |
0 |
0 |
T7 |
81228 |
10068 |
0 |
0 |
T8 |
525935 |
67780 |
0 |
0 |
T9 |
290759 |
34389 |
0 |
0 |
T10 |
80357 |
10620 |
0 |
0 |
T11 |
0 |
10425 |
0 |
0 |
T12 |
0 |
21936 |
0 |
0 |
T22 |
3211 |
0 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
31279 |
0 |
0 |
T3 |
61034 |
41 |
0 |
0 |
T4 |
389037 |
29 |
0 |
0 |
T5 |
245637 |
4 |
0 |
0 |
T6 |
253748 |
41 |
0 |
0 |
T7 |
81228 |
25 |
0 |
0 |
T8 |
525935 |
41 |
0 |
0 |
T9 |
290759 |
41 |
0 |
0 |
T10 |
80357 |
41 |
0 |
0 |
T11 |
0 |
33 |
0 |
0 |
T12 |
0 |
78 |
0 |
0 |
T22 |
3211 |
0 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T3 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: T3 T4 T5
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T3 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: T3 T4 T5
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T3 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: T3 T4 T5
135 1/1 txn_bits_q <= '0;
Tests: T3 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 | T3,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 | T3,T4,T5 |
1 | 1 | Covered | T3,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 | T3,T4,T5 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T3,T4,T5 |
1 | 1 | Covered | T3,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 |
T3,T4,T5 |
0 |
0 |
1 |
Covered |
T3,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 |
T3,T4,T5 |
0 |
0 |
1 |
Covered |
T3,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 |
12172535 |
0 |
0 |
T3 |
61034 |
197 |
0 |
0 |
T4 |
389037 |
23085 |
0 |
0 |
T5 |
245637 |
4759 |
0 |
0 |
T6 |
253748 |
16529 |
0 |
0 |
T7 |
81228 |
4656 |
0 |
0 |
T8 |
525935 |
1421 |
0 |
0 |
T9 |
290759 |
731 |
0 |
0 |
T10 |
80357 |
5068 |
0 |
0 |
T11 |
0 |
5008 |
0 |
0 |
T12 |
0 |
11636 |
0 |
0 |
T22 |
3211 |
0 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
15062 |
0 |
0 |
T3 |
61034 |
1 |
0 |
0 |
T4 |
389037 |
14 |
0 |
0 |
T5 |
245637 |
3 |
0 |
0 |
T6 |
253748 |
20 |
0 |
0 |
T7 |
81228 |
12 |
0 |
0 |
T8 |
525935 |
1 |
0 |
0 |
T9 |
290759 |
1 |
0 |
0 |
T10 |
80357 |
20 |
0 |
0 |
T11 |
0 |
16 |
0 |
0 |
T12 |
0 |
43 |
0 |
0 |
T22 |
3211 |
0 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T1 T2 T22
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 T22
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T1 T2 T22
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 T22
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T1 T2 T22
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 T22
135 1/1 txn_bits_q <= '0;
Tests: T1 T2 T22
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 | T1,T2,T22 |
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,T22 |
1 | 1 | Covered | T1,T2,T22 |
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,T2,T22 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T1,T2,T22 |
1 | 1 | Covered | T1,T2,T22 |
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 |
T1,T2,T22 |
0 |
0 |
1 |
Covered |
T1,T2,T22 |
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,T22 |
0 |
0 |
1 |
Covered |
T1,T2,T22 |
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 |
9610233 |
0 |
0 |
T1 |
41578 |
1399 |
0 |
0 |
T2 |
92499 |
358 |
0 |
0 |
T3 |
61034 |
0 |
0 |
0 |
T4 |
389037 |
0 |
0 |
0 |
T5 |
245637 |
2517 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T12 |
0 |
1124 |
0 |
0 |
T22 |
3211 |
122 |
0 |
0 |
T23 |
30985 |
1178 |
0 |
0 |
T25 |
0 |
808 |
0 |
0 |
T42 |
0 |
999 |
0 |
0 |
T43 |
0 |
1264 |
0 |
0 |
T53 |
0 |
1912 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
11787 |
0 |
0 |
T1 |
41578 |
1 |
0 |
0 |
T2 |
92499 |
1 |
0 |
0 |
T3 |
61034 |
0 |
0 |
0 |
T4 |
389037 |
0 |
0 |
0 |
T5 |
245637 |
2 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T12 |
0 |
5 |
0 |
0 |
T22 |
3211 |
1 |
0 |
0 |
T23 |
30985 |
1 |
0 |
0 |
T25 |
0 |
1 |
0 |
0 |
T42 |
0 |
1 |
0 |
0 |
T43 |
0 |
1 |
0 |
0 |
T53 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T1 T2 T22
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 T22
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T1 T2 T22
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 T22
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T1 T2 T22
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 T22
135 1/1 txn_bits_q <= '0;
Tests: T1 T2 T22
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 | T1,T2,T22 |
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,T22 |
1 | 1 | Covered | T1,T2,T22 |
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,T2,T22 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T1,T2,T22 |
1 | 1 | Covered | T1,T2,T22 |
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 |
T1,T2,T22 |
0 |
0 |
1 |
Covered |
T1,T2,T22 |
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,T22 |
0 |
0 |
1 |
Covered |
T1,T2,T22 |
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 |
9688476 |
0 |
0 |
T1 |
41578 |
1401 |
0 |
0 |
T2 |
92499 |
360 |
0 |
0 |
T3 |
61034 |
0 |
0 |
0 |
T4 |
389037 |
0 |
0 |
0 |
T5 |
245637 |
2521 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T12 |
0 |
1175 |
0 |
0 |
T22 |
3211 |
94 |
0 |
0 |
T23 |
30985 |
1190 |
0 |
0 |
T25 |
0 |
817 |
0 |
0 |
T42 |
0 |
1001 |
0 |
0 |
T43 |
0 |
1266 |
0 |
0 |
T53 |
0 |
1916 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
11779 |
0 |
0 |
T1 |
41578 |
1 |
0 |
0 |
T2 |
92499 |
1 |
0 |
0 |
T3 |
61034 |
0 |
0 |
0 |
T4 |
389037 |
0 |
0 |
0 |
T5 |
245637 |
2 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T12 |
0 |
5 |
0 |
0 |
T22 |
3211 |
1 |
0 |
0 |
T23 |
30985 |
1 |
0 |
0 |
T25 |
0 |
1 |
0 |
0 |
T42 |
0 |
1 |
0 |
0 |
T43 |
0 |
1 |
0 |
0 |
T53 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1732386 |
0 |
0 |
T5 |
245637 |
1438 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
993 |
0 |
0 |
T13 |
0 |
2645 |
0 |
0 |
T14 |
0 |
2101 |
0 |
0 |
T15 |
0 |
3113 |
0 |
0 |
T16 |
0 |
101 |
0 |
0 |
T17 |
0 |
484 |
0 |
0 |
T18 |
0 |
361 |
0 |
0 |
T19 |
0 |
489 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1901 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1891 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
3 |
0 |
0 |
T14 |
0 |
5 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1656396 |
0 |
0 |
T5 |
245637 |
1436 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
944 |
0 |
0 |
T13 |
0 |
1681 |
0 |
0 |
T14 |
0 |
1259 |
0 |
0 |
T15 |
0 |
3105 |
0 |
0 |
T16 |
0 |
97 |
0 |
0 |
T17 |
0 |
469 |
0 |
0 |
T18 |
0 |
339 |
0 |
0 |
T19 |
0 |
477 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1890 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1800 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1653202 |
0 |
0 |
T5 |
245637 |
1434 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
908 |
0 |
0 |
T13 |
0 |
1677 |
0 |
0 |
T14 |
0 |
1235 |
0 |
0 |
T15 |
0 |
3097 |
0 |
0 |
T16 |
0 |
88 |
0 |
0 |
T17 |
0 |
463 |
0 |
0 |
T18 |
0 |
323 |
0 |
0 |
T19 |
0 |
467 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1872 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1818 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1652249 |
0 |
0 |
T5 |
245637 |
1432 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
868 |
0 |
0 |
T13 |
0 |
1673 |
0 |
0 |
T14 |
0 |
1213 |
0 |
0 |
T15 |
0 |
3089 |
0 |
0 |
T16 |
0 |
110 |
0 |
0 |
T17 |
0 |
449 |
0 |
0 |
T18 |
0 |
398 |
0 |
0 |
T19 |
0 |
452 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1863 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1803 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1668862 |
0 |
0 |
T5 |
245637 |
1430 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
828 |
0 |
0 |
T13 |
0 |
1669 |
0 |
0 |
T14 |
0 |
1200 |
0 |
0 |
T15 |
0 |
3081 |
0 |
0 |
T16 |
0 |
99 |
0 |
0 |
T17 |
0 |
436 |
0 |
0 |
T18 |
0 |
378 |
0 |
0 |
T19 |
0 |
441 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1844 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1811 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1633270 |
0 |
0 |
T5 |
245637 |
1428 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
786 |
0 |
0 |
T13 |
0 |
1665 |
0 |
0 |
T14 |
0 |
1170 |
0 |
0 |
T15 |
0 |
3073 |
0 |
0 |
T16 |
0 |
84 |
0 |
0 |
T17 |
0 |
427 |
0 |
0 |
T18 |
0 |
360 |
0 |
0 |
T19 |
0 |
427 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1831 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1798 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1644507 |
0 |
0 |
T5 |
245637 |
1426 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
900 |
0 |
0 |
T13 |
0 |
1661 |
0 |
0 |
T14 |
0 |
1148 |
0 |
0 |
T15 |
0 |
3065 |
0 |
0 |
T16 |
0 |
108 |
0 |
0 |
T17 |
0 |
414 |
0 |
0 |
T18 |
0 |
333 |
0 |
0 |
T19 |
0 |
418 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1818 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1797 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1639202 |
0 |
0 |
T5 |
245637 |
1424 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
868 |
0 |
0 |
T13 |
0 |
1657 |
0 |
0 |
T14 |
0 |
1125 |
0 |
0 |
T15 |
0 |
3057 |
0 |
0 |
T16 |
0 |
91 |
0 |
0 |
T17 |
0 |
409 |
0 |
0 |
T18 |
0 |
359 |
0 |
0 |
T19 |
0 |
407 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1809 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1832 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1710753 |
0 |
0 |
T5 |
245637 |
1422 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
990 |
0 |
0 |
T13 |
0 |
2611 |
0 |
0 |
T14 |
0 |
1912 |
0 |
0 |
T15 |
0 |
3049 |
0 |
0 |
T16 |
0 |
118 |
0 |
0 |
T17 |
0 |
402 |
0 |
0 |
T18 |
0 |
341 |
0 |
0 |
T19 |
0 |
401 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1797 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1912 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
3 |
0 |
0 |
T14 |
0 |
5 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1634314 |
0 |
0 |
T5 |
245637 |
1420 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
952 |
0 |
0 |
T13 |
0 |
1649 |
0 |
0 |
T14 |
0 |
1079 |
0 |
0 |
T15 |
0 |
3041 |
0 |
0 |
T16 |
0 |
104 |
0 |
0 |
T17 |
0 |
382 |
0 |
0 |
T18 |
0 |
370 |
0 |
0 |
T19 |
0 |
385 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1779 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1823 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1658531 |
0 |
0 |
T5 |
245637 |
1418 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
918 |
0 |
0 |
T13 |
0 |
1645 |
0 |
0 |
T14 |
0 |
1056 |
0 |
0 |
T15 |
0 |
3033 |
0 |
0 |
T16 |
0 |
90 |
0 |
0 |
T17 |
0 |
500 |
0 |
0 |
T18 |
0 |
347 |
0 |
0 |
T19 |
0 |
381 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1770 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1834 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1596160 |
0 |
0 |
T5 |
245637 |
1416 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
868 |
0 |
0 |
T13 |
0 |
1641 |
0 |
0 |
T14 |
0 |
1029 |
0 |
0 |
T15 |
0 |
3025 |
0 |
0 |
T16 |
0 |
86 |
0 |
0 |
T17 |
0 |
493 |
0 |
0 |
T18 |
0 |
373 |
0 |
0 |
T19 |
0 |
495 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1754 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1789 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1637431 |
0 |
0 |
T5 |
245637 |
1414 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
824 |
0 |
0 |
T13 |
0 |
1637 |
0 |
0 |
T14 |
0 |
1015 |
0 |
0 |
T15 |
0 |
3017 |
0 |
0 |
T16 |
0 |
82 |
0 |
0 |
T17 |
0 |
478 |
0 |
0 |
T18 |
0 |
354 |
0 |
0 |
T19 |
0 |
489 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1743 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1847 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1654655 |
0 |
0 |
T5 |
245637 |
1412 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
865 |
0 |
0 |
T13 |
0 |
1633 |
0 |
0 |
T14 |
0 |
992 |
0 |
0 |
T15 |
0 |
3009 |
0 |
0 |
T16 |
0 |
116 |
0 |
0 |
T17 |
0 |
465 |
0 |
0 |
T18 |
0 |
337 |
0 |
0 |
T19 |
0 |
470 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1737 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1848 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1664394 |
0 |
0 |
T5 |
245637 |
1410 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
889 |
0 |
0 |
T13 |
0 |
1629 |
0 |
0 |
T14 |
0 |
1084 |
0 |
0 |
T15 |
0 |
3001 |
0 |
0 |
T16 |
0 |
101 |
0 |
0 |
T17 |
0 |
456 |
0 |
0 |
T18 |
0 |
366 |
0 |
0 |
T19 |
0 |
461 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1719 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1874 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T5 T12 T13
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: T5 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T5 T12 T13
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: T5 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T5 T12 T13
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: T5 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T5 T12 T13
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 | T5,T12,T13 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 | T5,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T5,T12,T13 |
1 | 1 | Covered | T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
T5,T12,T13 |
0 |
0 |
1 |
Covered |
T5,T12,T13 |
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 |
1624267 |
0 |
0 |
T5 |
245637 |
1408 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
929 |
0 |
0 |
T13 |
0 |
1625 |
0 |
0 |
T14 |
0 |
1053 |
0 |
0 |
T15 |
0 |
2993 |
0 |
0 |
T16 |
0 |
94 |
0 |
0 |
T17 |
0 |
439 |
0 |
0 |
T18 |
0 |
354 |
0 |
0 |
T19 |
0 |
454 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1710 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1842 |
0 |
0 |
T5 |
245637 |
1 |
0 |
0 |
T6 |
253748 |
0 |
0 |
0 |
T7 |
81228 |
0 |
0 |
0 |
T8 |
525935 |
0 |
0 |
0 |
T9 |
290759 |
0 |
0 |
0 |
T10 |
80357 |
0 |
0 |
0 |
T11 |
700025 |
0 |
0 |
0 |
T12 |
0 |
4 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T18 |
0 |
2 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T23 |
30985 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T42 |
424328 |
0 |
0 |
0 |
T43 |
41569 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T12 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: T12 T13 T14
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T12 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: T12 T13 T14
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T12 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: T12 T13 T14
135 1/1 txn_bits_q <= '0;
Tests: T12 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 | T12,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 | T12,T13,T14 |
1 | 1 | Covered | T12,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 | T12,T13,T14 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T12,T13,T14 |
1 | 1 | Covered | T12,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 |
T12,T13,T14 |
0 |
0 |
1 |
Covered |
T12,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 |
T12,T13,T14 |
0 |
0 |
1 |
Covered |
T12,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 |
1199354 |
0 |
0 |
T12 |
485034 |
432 |
0 |
0 |
T13 |
393091 |
1609 |
0 |
0 |
T14 |
595340 |
313 |
0 |
0 |
T15 |
0 |
921 |
0 |
0 |
T17 |
0 |
408 |
0 |
0 |
T19 |
0 |
418 |
0 |
0 |
T21 |
0 |
143 |
0 |
0 |
T24 |
148498 |
0 |
0 |
0 |
T25 |
174668 |
0 |
0 |
0 |
T26 |
821468 |
0 |
0 |
0 |
T27 |
583962 |
0 |
0 |
0 |
T28 |
18603 |
0 |
0 |
0 |
T29 |
412987 |
0 |
0 |
0 |
T30 |
959815 |
0 |
0 |
0 |
T31 |
0 |
1669 |
0 |
0 |
T41 |
0 |
486 |
0 |
0 |
T54 |
0 |
461 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1347 |
0 |
0 |
T12 |
485034 |
2 |
0 |
0 |
T13 |
393091 |
2 |
0 |
0 |
T14 |
595340 |
1 |
0 |
0 |
T15 |
0 |
1 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T19 |
0 |
1 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T24 |
148498 |
0 |
0 |
0 |
T25 |
174668 |
0 |
0 |
0 |
T26 |
821468 |
0 |
0 |
0 |
T27 |
583962 |
0 |
0 |
0 |
T28 |
18603 |
0 |
0 |
0 |
T29 |
412987 |
0 |
0 |
0 |
T30 |
959815 |
0 |
0 |
0 |
T31 |
0 |
1 |
0 |
0 |
T41 |
0 |
2 |
0 |
0 |
T54 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
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: T14 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: T14 T16 T17
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T14 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: T14 T16 T17
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T14 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: T14 T16 T17
135 1/1 txn_bits_q <= '0;
Tests: T14 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 | T14,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 | T14,T16,T17 |
1 | 1 | Covered | T14,T16,T17 |
LINE 123
EXPRESSION (src_wd_i & BitMask)
----1--- ---2---
-1- | -2- | Status | Tests |
0 | - | Covered | T14,T16,T17 |
1 | - | Covered | T14,T16,T17 |
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 | T14,T16,T17 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T14,T16,T17 |
1 | 1 | Covered | T14,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 |
T14,T16,T17 |
0 |
0 |
1 |
Covered |
T14,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 |
T14,T16,T17 |
0 |
0 |
1 |
Covered |
T14,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 |
13956107 |
0 |
0 |
T14 |
595340 |
2610 |
0 |
0 |
T15 |
560305 |
0 |
0 |
0 |
T16 |
133794 |
235 |
0 |
0 |
T17 |
0 |
866 |
0 |
0 |
T18 |
0 |
729 |
0 |
0 |
T19 |
0 |
984 |
0 |
0 |
T20 |
0 |
710 |
0 |
0 |
T21 |
0 |
475 |
0 |
0 |
T31 |
249804 |
0 |
0 |
0 |
T41 |
0 |
1031 |
0 |
0 |
T44 |
758199 |
0 |
0 |
0 |
T45 |
542784 |
0 |
0 |
0 |
T46 |
821899 |
0 |
0 |
0 |
T47 |
341689 |
0 |
0 |
0 |
T48 |
231870 |
0 |
0 |
0 |
T54 |
0 |
876 |
0 |
0 |
T55 |
0 |
1077 |
0 |
0 |
T56 |
3704 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32428936 |
32132226 |
0 |
0 |
T1 |
81 |
4 |
0 |
0 |
T2 |
770 |
16 |
0 |
0 |
T3 |
1219 |
1169 |
0 |
0 |
T4 |
801 |
708 |
0 |
0 |
T5 |
510 |
182 |
0 |
0 |
T6 |
1055 |
997 |
0 |
0 |
T7 |
675 |
600 |
0 |
0 |
T8 |
1105 |
1052 |
0 |
0 |
T22 |
106 |
30 |
0 |
0 |
T23 |
63 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
16618 |
0 |
0 |
T14 |
595340 |
6 |
0 |
0 |
T15 |
560305 |
0 |
0 |
0 |
T16 |
133794 |
2 |
0 |
0 |
T17 |
0 |
2 |
0 |
0 |
T18 |
0 |
4 |
0 |
0 |
T19 |
0 |
2 |
0 |
0 |
T20 |
0 |
2 |
0 |
0 |
T21 |
0 |
2 |
0 |
0 |
T31 |
249804 |
0 |
0 |
0 |
T41 |
0 |
4 |
0 |
0 |
T44 |
758199 |
0 |
0 |
0 |
T45 |
542784 |
0 |
0 |
0 |
T46 |
821899 |
0 |
0 |
0 |
T47 |
341689 |
0 |
0 |
0 |
T48 |
231870 |
0 |
0 |
0 |
T54 |
0 |
2 |
0 |
0 |
T55 |
0 |
4 |
0 |
0 |
T56 |
3704 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
41578 |
41522 |
0 |
0 |
T2 |
92499 |
91613 |
0 |
0 |
T3 |
61034 |
60968 |
0 |
0 |
T4 |
389037 |
388945 |
0 |
0 |
T5 |
245637 |
242806 |
0 |
0 |
T6 |
253748 |
253698 |
0 |
0 |
T7 |
81228 |
81133 |
0 |
0 |
T8 |
525935 |
525846 |
0 |
0 |
T22 |
3211 |
3120 |
0 |
0 |
T23 |
30985 |
30919 |
0 |
0 |