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 | T6,T10,T11 |
1 | 0 | Covered | T1,T2,T3 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T1,T2,T3 |
1 | 1 | Covered | T1,T2,T3 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T1,T3,T4 |
1 | 0 | Covered | T1,T2,T3 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T1,T2,T3 |
1 | 1 | Covered | T1,T2,T3 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Not Covered | |
1 | 1 | Covered | T1,T3,T4 |
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 | T10,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 | T10,T12,T13 |
1 | 1 | Covered | T10,T12,T13 |
LINE 123
EXPRESSION (src_wd_i & BitMask)
----1--- ---2---
-1- | -2- | Status | Tests |
0 | - | Covered | T10,T12,T13 |
1 | - | Covered | T10,T12,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 | T10,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T10,T12,T13 |
1 | 1 | Covered | T10,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 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 |
177774981 |
0 |
0 |
T1 |
275894 |
32512 |
0 |
0 |
T2 |
21894 |
0 |
0 |
0 |
T3 |
63265 |
7659 |
0 |
0 |
T4 |
26861 |
3022 |
0 |
0 |
T5 |
355835 |
45449 |
0 |
0 |
T6 |
5035638 |
63534 |
0 |
0 |
T7 |
5315968 |
38456 |
0 |
0 |
T8 |
14026887 |
14014 |
0 |
0 |
T9 |
1454464 |
12165 |
0 |
0 |
T10 |
6571843 |
41010 |
0 |
0 |
T11 |
5606753 |
29940 |
0 |
0 |
T12 |
171441 |
2204 |
0 |
0 |
T13 |
0 |
7369 |
0 |
0 |
T14 |
0 |
6028 |
0 |
0 |
T15 |
0 |
2816 |
0 |
0 |
T16 |
0 |
6589 |
0 |
0 |
T17 |
0 |
3986 |
0 |
0 |
T18 |
0 |
671 |
0 |
0 |
T19 |
183376 |
0 |
0 |
0 |
T20 |
38107 |
0 |
0 |
0 |
T21 |
421088 |
0 |
0 |
0 |
T22 |
13178224 |
0 |
0 |
0 |
T23 |
6959137 |
0 |
0 |
0 |
T24 |
9282663 |
0 |
0 |
0 |
T36 |
0 |
24494 |
0 |
0 |
T37 |
0 |
876 |
0 |
0 |
T38 |
0 |
2736 |
0 |
0 |
T39 |
0 |
2119 |
0 |
0 |
T40 |
766469 |
0 |
0 |
0 |
T41 |
117799 |
0 |
0 |
0 |
T42 |
35137 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
839375160 |
831264824 |
0 |
0 |
T1 |
29848 |
28314 |
0 |
0 |
T2 |
2236 |
156 |
0 |
0 |
T3 |
29874 |
28158 |
0 |
0 |
T4 |
17420 |
14976 |
0 |
0 |
T5 |
18642 |
16796 |
0 |
0 |
T6 |
26364 |
15730 |
0 |
0 |
T7 |
30056 |
27560 |
0 |
0 |
T8 |
164996 |
162838 |
0 |
0 |
T19 |
19422 |
182 |
0 |
0 |
T20 |
2522 |
130 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
188046 |
0 |
0 |
T1 |
275894 |
41 |
0 |
0 |
T2 |
21894 |
0 |
0 |
0 |
T3 |
63265 |
41 |
0 |
0 |
T4 |
26861 |
23 |
0 |
0 |
T5 |
355835 |
27 |
0 |
0 |
T6 |
5035638 |
40 |
0 |
0 |
T7 |
5315968 |
41 |
0 |
0 |
T8 |
14026887 |
31 |
0 |
0 |
T9 |
1454464 |
27 |
0 |
0 |
T10 |
6571843 |
101 |
0 |
0 |
T11 |
5606753 |
41 |
0 |
0 |
T12 |
171441 |
18 |
0 |
0 |
T13 |
0 |
21 |
0 |
0 |
T14 |
0 |
54 |
0 |
0 |
T15 |
0 |
36 |
0 |
0 |
T16 |
0 |
36 |
0 |
0 |
T17 |
0 |
18 |
0 |
0 |
T18 |
0 |
4 |
0 |
0 |
T19 |
183376 |
0 |
0 |
0 |
T20 |
38107 |
0 |
0 |
0 |
T21 |
421088 |
0 |
0 |
0 |
T22 |
13178224 |
0 |
0 |
0 |
T23 |
6959137 |
0 |
0 |
0 |
T24 |
9282663 |
0 |
0 |
0 |
T36 |
0 |
17 |
0 |
0 |
T37 |
0 |
2 |
0 |
0 |
T38 |
0 |
14 |
0 |
0 |
T39 |
0 |
1 |
0 |
0 |
T40 |
766469 |
0 |
0 |
0 |
T41 |
117799 |
0 |
0 |
0 |
T42 |
35137 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
7173244 |
7171242 |
0 |
0 |
T2 |
569244 |
567632 |
0 |
0 |
T3 |
1644890 |
1643226 |
0 |
0 |
T4 |
698386 |
696150 |
0 |
0 |
T5 |
9251710 |
9249474 |
0 |
0 |
T6 |
7701564 |
7623746 |
0 |
0 |
T7 |
8130304 |
8128068 |
0 |
0 |
T8 |
21452886 |
21451248 |
0 |
0 |
T19 |
4767776 |
4749316 |
0 |
0 |
T20 |
990782 |
989066 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_0_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 17 | 16 | 94.12 |
CONT_ASSIGN | 65 | 0 | 0 | |
ALWAYS | 71 | 5 | 4 | 80.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 7 | 7 | 100.00 |
CONT_ASSIGN | 150 | 0 | 0 | |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 unreachable assign src_req = src_we_i | src_re_i;
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 unreachable src_busy_q <= 1'b1;
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 0/1 ==> src_busy_q <= 1'b0;
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 unreachable src_q <= src_wd_i & BitMask;
124 unreachable txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T1 T3 T4
135 1/1 txn_bits_q <= '0;
Tests: T1 T3 T4
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 unreachable assign unused_wd = ^src_wd_i;
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_0_cdc
| Total | Covered | Percent |
Conditions | 7 | 6 | 85.71 |
Logical | 7 | 6 | 85.71 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Unreachable | |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Excluded | |
VC_COV_UNR |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T1,T3,T4 |
1 | 0 | Excluded | |
VC_COV_UNR |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Not Covered | |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Excluded | |
VC_COV_UNR |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Covered | T1,T3,T4 |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_0_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
6 |
5 |
83.33 |
IF |
71 |
3 |
2 |
66.67 |
IF |
115 |
3 |
3 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==> (Unreachable)
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Unreachable |
|
0 |
0 |
1 |
Not Covered |
|
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==> (Unreachable)
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Unreachable |
|
0 |
0 |
1 |
Covered |
T1,T3,T4 |
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 |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
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 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_1_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 17 | 16 | 94.12 |
CONT_ASSIGN | 65 | 0 | 0 | |
ALWAYS | 71 | 5 | 4 | 80.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 7 | 7 | 100.00 |
CONT_ASSIGN | 150 | 0 | 0 | |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 unreachable assign src_req = src_we_i | src_re_i;
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 unreachable src_busy_q <= 1'b1;
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 0/1 ==> src_busy_q <= 1'b0;
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 unreachable src_q <= src_wd_i & BitMask;
124 unreachable txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T1 T3 T4
135 1/1 txn_bits_q <= '0;
Tests: T1 T3 T4
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 unreachable assign unused_wd = ^src_wd_i;
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_1_cdc
| Total | Covered | Percent |
Conditions | 7 | 6 | 85.71 |
Logical | 7 | 6 | 85.71 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Unreachable | |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Excluded | |
VC_COV_UNR |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T1,T3,T4 |
1 | 0 | Excluded | |
VC_COV_UNR |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Not Covered | |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Excluded | |
VC_COV_UNR |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests | Exclude Annotation |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Excluded | |
VC_COV_UNR |
1 | 1 | Covered | T1,T3,T4 |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_chn_val_1_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
6 |
5 |
83.33 |
IF |
71 |
3 |
2 |
66.67 |
IF |
115 |
3 |
3 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==> (Unreachable)
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Unreachable |
|
0 |
0 |
1 |
Not Covered |
|
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==> (Unreachable)
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Unreachable |
|
0 |
0 |
1 |
Covered |
T1,T3,T4 |
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 |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
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 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T10 T11 T12
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: T10 T11 T12
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T10 T11 T12
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: T10 T11 T12
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T10 T11 T12
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T10,T11,T12 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T10,T11,T12 |
1 | 1 | Covered | T10,T11,T12 |
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 | T6,T10,T11 |
1 | 0 | Covered | T10,T11,T12 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T10,T11,T12 |
1 | 1 | Covered | T10,T11,T12 |
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 | T6,T10,T11 |
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 |
T10,T11,T12 |
0 |
0 |
1 |
Covered |
T10,T11,T12 |
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 |
T10,T11,T12 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
59171018 |
0 |
0 |
T10 |
386579 |
425 |
0 |
0 |
T11 |
329809 |
733 |
0 |
0 |
T12 |
171441 |
11707 |
0 |
0 |
T13 |
236299 |
326 |
0 |
0 |
T14 |
210446 |
15109 |
0 |
0 |
T15 |
0 |
14909 |
0 |
0 |
T16 |
0 |
28122 |
0 |
0 |
T17 |
0 |
21621 |
0 |
0 |
T18 |
0 |
20301 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T37 |
0 |
40557 |
0 |
0 |
T40 |
766469 |
0 |
0 |
0 |
T41 |
117799 |
0 |
0 |
0 |
T42 |
35137 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
64360 |
0 |
0 |
T10 |
386579 |
1 |
0 |
0 |
T11 |
329809 |
1 |
0 |
0 |
T12 |
171441 |
77 |
0 |
0 |
T13 |
236299 |
1 |
0 |
0 |
T14 |
210446 |
138 |
0 |
0 |
T15 |
0 |
143 |
0 |
0 |
T16 |
0 |
142 |
0 |
0 |
T17 |
0 |
78 |
0 |
0 |
T18 |
0 |
144 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T37 |
0 |
93 |
0 |
0 |
T40 |
766469 |
0 |
0 |
0 |
T41 |
117799 |
0 |
0 |
0 |
T42 |
35137 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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 T3 T4
135 1/1 txn_bits_q <= '0;
Tests: T1 T3 T4
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 | T6,T10,T11 |
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 | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Covered | T1,T3,T4 |
1 | 0 | Covered | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Not Covered | |
1 | 1 | Covered | T1,T3,T4 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T1,T3,T4 |
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 |
95492 |
0 |
0 |
T6 |
296214 |
2130 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
967 |
0 |
0 |
T11 |
329809 |
1087 |
0 |
0 |
T13 |
0 |
816 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T25 |
0 |
1521 |
0 |
0 |
T36 |
0 |
2073 |
0 |
0 |
T38 |
0 |
766 |
0 |
0 |
T39 |
0 |
2119 |
0 |
0 |
T43 |
0 |
1299 |
0 |
0 |
T44 |
0 |
1644 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
86 |
0 |
0 |
T6 |
296214 |
1 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1 |
0 |
0 |
T11 |
329809 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T25 |
0 |
1 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
T38 |
0 |
1 |
0 |
0 |
T39 |
0 |
1 |
0 |
0 |
T43 |
0 |
1 |
0 |
0 |
T44 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_en_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T1 T3 T4
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 T3 T4
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T1 T3 T4
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 T3 T4
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T1 T3 T4
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 T3 T4
135 1/1 txn_bits_q <= '0;
Tests: T1 T3 T4
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_en_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T1,T3,T4 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T1,T3,T4 |
1 | 1 | Covered | T1,T3,T4 |
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,T3,T4 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T1,T3,T4 |
1 | 1 | Covered | T1,T3,T4 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_en_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T1,T3,T4 |
0 |
0 |
1 |
Covered |
T1,T3,T4 |
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,T3,T4 |
0 |
0 |
1 |
Covered |
T1,T3,T4 |
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 |
31758519 |
0 |
0 |
T1 |
275894 |
32512 |
0 |
0 |
T2 |
21894 |
0 |
0 |
0 |
T3 |
63265 |
7659 |
0 |
0 |
T4 |
26861 |
3022 |
0 |
0 |
T5 |
355835 |
45449 |
0 |
0 |
T6 |
296214 |
10578 |
0 |
0 |
T7 |
312704 |
38456 |
0 |
0 |
T8 |
825111 |
14014 |
0 |
0 |
T9 |
0 |
12165 |
0 |
0 |
T10 |
0 |
18838 |
0 |
0 |
T11 |
0 |
5877 |
0 |
0 |
T19 |
183376 |
0 |
0 |
0 |
T20 |
38107 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
32648 |
0 |
0 |
T1 |
275894 |
41 |
0 |
0 |
T2 |
21894 |
0 |
0 |
0 |
T3 |
63265 |
41 |
0 |
0 |
T4 |
26861 |
23 |
0 |
0 |
T5 |
355835 |
27 |
0 |
0 |
T6 |
296214 |
7 |
0 |
0 |
T7 |
312704 |
41 |
0 |
0 |
T8 |
825111 |
31 |
0 |
0 |
T9 |
0 |
27 |
0 |
0 |
T10 |
0 |
48 |
0 |
0 |
T11 |
0 |
8 |
0 |
0 |
T19 |
183376 |
0 |
0 |
0 |
T20 |
38107 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_pd_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T1 T3 T4
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 T3 T4
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T1 T3 T4
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 T3 T4
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T1 T3 T4
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 T3 T4
135 1/1 txn_bits_q <= '0;
Tests: T1 T3 T4
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_pd_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T1,T3,T4 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T1,T3,T4 |
1 | 1 | Covered | T1,T3,T4 |
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,T3,T4 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T1,T3,T4 |
1 | 1 | Covered | T1,T3,T4 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_pd_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T1,T3,T4 |
0 |
0 |
1 |
Covered |
T1,T3,T4 |
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,T3,T4 |
0 |
0 |
1 |
Covered |
T1,T3,T4 |
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 |
15130060 |
0 |
0 |
T1 |
275894 |
934 |
0 |
0 |
T2 |
21894 |
0 |
0 |
0 |
T3 |
63265 |
217 |
0 |
0 |
T4 |
26861 |
1380 |
0 |
0 |
T5 |
355835 |
21091 |
0 |
0 |
T6 |
296214 |
6278 |
0 |
0 |
T7 |
312704 |
806 |
0 |
0 |
T8 |
825111 |
6999 |
0 |
0 |
T9 |
0 |
5520 |
0 |
0 |
T10 |
0 |
4199 |
0 |
0 |
T11 |
0 |
4089 |
0 |
0 |
T19 |
183376 |
0 |
0 |
0 |
T20 |
38107 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
15862 |
0 |
0 |
T1 |
275894 |
1 |
0 |
0 |
T2 |
21894 |
0 |
0 |
0 |
T3 |
63265 |
1 |
0 |
0 |
T4 |
26861 |
11 |
0 |
0 |
T5 |
355835 |
13 |
0 |
0 |
T6 |
296214 |
5 |
0 |
0 |
T7 |
312704 |
1 |
0 |
0 |
T8 |
825111 |
15 |
0 |
0 |
T9 |
0 |
13 |
0 |
0 |
T10 |
0 |
11 |
0 |
0 |
T11 |
0 |
6 |
0 |
0 |
T19 |
183376 |
0 |
0 |
0 |
T20 |
38107 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_lp_sample_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T2 T19 T20
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T2 T19 T20
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T2 T19 T20
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T2 T19 T20
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T2 T19 T20
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T2 T19 T20
135 1/1 txn_bits_q <= '0;
Tests: T2 T19 T20
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_lp_sample_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T2,T19,T20 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T2,T19,T20 |
1 | 1 | Covered | T2,T19,T20 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T2,T19,T20 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T2,T19,T20 |
1 | 1 | Covered | T2,T19,T20 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_lp_sample_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T2,T19,T20 |
0 |
0 |
1 |
Covered |
T2,T19,T20 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T2,T19,T20 |
0 |
0 |
1 |
Covered |
T2,T19,T20 |
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 |
12532085 |
0 |
0 |
T2 |
21894 |
712 |
0 |
0 |
T3 |
63265 |
0 |
0 |
0 |
T4 |
26861 |
0 |
0 |
0 |
T5 |
355835 |
0 |
0 |
0 |
T6 |
296214 |
5979 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
0 |
2429 |
0 |
0 |
T11 |
0 |
3114 |
0 |
0 |
T19 |
183376 |
968 |
0 |
0 |
T20 |
38107 |
1379 |
0 |
0 |
T21 |
0 |
1033 |
0 |
0 |
T22 |
0 |
1491 |
0 |
0 |
T23 |
0 |
1438 |
0 |
0 |
T42 |
0 |
1457 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
12875 |
0 |
0 |
T2 |
21894 |
1 |
0 |
0 |
T3 |
63265 |
0 |
0 |
0 |
T4 |
26861 |
0 |
0 |
0 |
T5 |
355835 |
0 |
0 |
0 |
T6 |
296214 |
4 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
0 |
6 |
0 |
0 |
T11 |
0 |
4 |
0 |
0 |
T19 |
183376 |
1 |
0 |
0 |
T20 |
38107 |
1 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T22 |
0 |
1 |
0 |
0 |
T23 |
0 |
1 |
0 |
0 |
T42 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
0 |
0 |
Line Coverage for Instance : tb.dut.u_reg.u_adc_sample_ctl_cdc
| Line No. | Total | Covered | Percent |
TOTAL | | 22 | 22 | 100.00 |
CONT_ASSIGN | 65 | 1 | 1 | 100.00 |
ALWAYS | 71 | 6 | 6 | 100.00 |
CONT_ASSIGN | 85 | 1 | 1 | 100.00 |
CONT_ASSIGN | 109 | 1 | 1 | 100.00 |
ALWAYS | 115 | 9 | 9 | 100.00 |
CONT_ASSIGN | 150 | 1 | 1 | 100.00 |
CONT_ASSIGN | 155 | 1 | 1 | 100.00 |
CONT_ASSIGN | 156 | 1 | 1 | 100.00 |
CONT_ASSIGN | 200 | 1 | 1 | 100.00 |
64
65 1/1 assign src_req = src_we_i | src_re_i;
Tests: T2 T19 T20
66
67 // busy indication back-pressures upstream if the register is accessed
68 // again. The busy indication is also used as a "commit" indication for
69 // resolving software and hardware write conflicts
70 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
71 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
72 1/1 src_busy_q <= '0;
Tests: T1 T2 T3
73 1/1 end else if (src_req) begin
Tests: T1 T2 T3
74 1/1 src_busy_q <= 1'b1;
Tests: T2 T19 T20
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T2 T19 T20
77 end
MISSING_ELSE
78 end
79
80 // A src_ack should only be sent if there was a src_req.
81 // src_busy_q asserts whenever there is a src_req. By association,
82 // whenever src_ack is seen, then src_busy must be high.
83 `ASSERT(SrcAckBusyChk_A, src_ack |-> src_busy_q, clk_src_i, !rst_src_ni)
84
85 1/1 assign src_busy_o = src_busy_q;
Tests: T1 T2 T3
86
87 // src_q acts as both the write holding register and the software read back
88 // register.
89 // When software performs a write, the write data is captured in src_q for
90 // CDC purposes. When not performing a write, the src_q reflects the most recent
91 // hardware value. For registers with no hardware access, this is simply the
92 // the value programmed by software (or in the case R1C, W1C etc) the value after
93 // the operation. For registers with hardware access, this reflects a potentially
94 // delayed version of the real value, as the software facing updates lag real
95 // time updates.
96 //
97 // To resolve software and hardware conflicts, the process is as follows:
98 // When software issues a write, this module asserts "busy". While busy,
99 // src_q does not take on destination value updates. Since the
100 // logic has committed to updating based on software command, there is an irreversible
101 // window from which hardware writes are ignored. Once the busy window completes,
102 // the cdc portion then begins sampling once more.
103 //
104 // This is consistent with prim_subreg_arb where during software / hardware conflicts,
105 // software is always prioritized. The main difference is the conflict resolution window
106 // is now larger instead of just one destination clock cycle.
107
108 logic busy;
109 1/1 assign busy = src_busy_q & !src_ack;
Tests: T1 T2 T3
110
111 // This is the current destination value
112 logic [DataWidth-1:0] dst_qs;
113 logic src_update;
114 always_ff @(posedge clk_src_i or negedge rst_src_ni) begin
115 1/1 if (!rst_src_ni) begin
Tests: T1 T2 T3
116 1/1 src_q <= ResetVal;
Tests: T1 T2 T3
117 1/1 txn_bits_q <= '0;
Tests: T1 T2 T3
118 1/1 end else if (src_req) begin
Tests: T1 T2 T3
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 1/1 src_q <= src_wd_i & BitMask;
Tests: T2 T19 T20
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T2 T19 T20
125 1/1 end else if (src_busy_q && src_ack || src_update && !busy) begin
Tests: T1 T2 T3
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 1/1 src_q <= dst_qs;
Tests: T2 T19 T20
135 1/1 txn_bits_q <= '0;
Tests: T2 T19 T20
136 end
MISSING_ELSE
137 end
138
139 // The current design (tlul_adapter_reg) does not spit out a request if the destination it chooses
140 // (decoded from address) is busy. So this creates a situation in the current design where
141 // src_req_i and busy can never be high at the same time.
142 // While the code above could be coded directly to be expressed as `src_req & !busy`, which makes
143 // the intent clearer, it ends up causing coverage holes from the tool's perspective since that
144 // condition cannot be met.
145 // Thus we add an assertion here to ensure the condition is always satisfied.
146 `ASSERT(BusySrcReqChk_A, busy |-> !src_req, clk_src_i, !rst_src_ni)
147
148 // reserved bits are not used
149 logic unused_wd;
150 1/1 assign unused_wd = ^src_wd_i;
Tests: T1 T2 T3
151
152 // src_q is always updated in the clk_src domain.
153 // when performing an update to the destination domain, it is guaranteed
154 // to not change by protocol.
155 1/1 assign src_qs_o = src_q;
Tests: T1 T2 T3
156 1/1 assign dst_wd_o = src_q;
Tests: T1 T2 T3
157
158 ////////////////////////////
159 // CDC handling
160 ////////////////////////////
161
162 logic dst_req_from_src;
163 logic dst_req;
164
165
166 // the software transaction is pulse synced across the domain.
167 // the prim_reg_cdc_arb module handles conflicts with ongoing hardware updates.
168 prim_pulse_sync u_src_to_dst_req (
169 .clk_src_i,
170 .rst_src_ni,
171 .clk_dst_i,
172 .rst_dst_ni,
173 .src_pulse_i(src_req),
174 .dst_pulse_o(dst_req_from_src)
175 );
176
177 prim_reg_cdc_arb #(
178 .DataWidth(DataWidth),
179 .ResetVal(ResetVal),
180 .DstWrReq(DstWrReq)
181 ) u_arb (
182 .clk_src_i,
183 .rst_src_ni,
184 .clk_dst_i,
185 .rst_dst_ni,
186 .src_ack_o(src_ack),
187 .src_update_o(src_update),
188 .dst_req_i(dst_req_from_src),
189 .dst_req_o(dst_req),
190 .dst_update_i,
191 .dst_ds_i,
192 .dst_qs_i,
193 .dst_qs_o(dst_qs)
194 );
195
196
197 // Each is valid only when destination request pulse is high; this is important in not propagating
198 // the internal assertion of 'dst_req' by the 'prim_pulse_sync' channel when just one domain is
199 // reset.
200 1/1 assign {dst_we_o, dst_re_o, dst_regwen_o} = txn_bits_q & {TxnWidth{dst_req}};
Tests: T1 T2 T3
Cond Coverage for Instance : tb.dut.u_reg.u_adc_sample_ctl_cdc
| Total | Covered | Percent |
Conditions | 11 | 10 | 90.91 |
Logical | 11 | 10 | 90.91 |
Non-Logical | 0 | 0 | |
Event | 0 | 0 | |
LINE 65
EXPRESSION (src_we_i | src_re_i)
----1--- ----2---
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T2,T19,T20 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T2,T19,T20 |
1 | 1 | Covered | T2,T19,T20 |
LINE 125
EXPRESSION ((src_busy_q && src_ack) || (src_update && ((!busy))))
-----------1----------- ------------2------------
-1- | -2- | Status | Tests |
0 | 0 | Covered | T1,T2,T3 |
0 | 1 | Unreachable | |
1 | 0 | Covered | T2,T19,T20 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T2,T19,T20 |
1 | 1 | Covered | T2,T19,T20 |
LINE 125
SUB-EXPRESSION (src_update && ((!busy)))
-----1---- ----2----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Unreachable | |
1 | 1 | Unreachable | |
Branch Coverage for Instance : tb.dut.u_reg.u_adc_sample_ctl_cdc
| Line No. | Total | Covered | Percent |
Branches |
|
8 |
8 |
100.00 |
IF |
71 |
4 |
4 |
100.00 |
IF |
115 |
4 |
4 |
100.00 |
71 if (!rst_src_ni) begin
-1-
72 src_busy_q <= '0;
==>
73 end else if (src_req) begin
-2-
74 src_busy_q <= 1'b1;
==>
75 end else if (src_ack) begin
-3-
76 src_busy_q <= 1'b0;
==>
77 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T2,T19,T20 |
0 |
0 |
1 |
Covered |
T2,T19,T20 |
0 |
0 |
0 |
Covered |
T1,T2,T3 |
115 if (!rst_src_ni) begin
-1-
116 src_q <= ResetVal;
==>
117 txn_bits_q <= '0;
118 end else if (src_req) begin
-2-
119 // See assertion below
120 // At the beginning of a software initiated transaction, the following
121 // values are captured in the src_q/txn_bits_q flops to ensure they cannot
122 // change for the duration of the synchronization operation.
123 src_q <= src_wd_i & BitMask;
==>
124 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
125 end else if (src_busy_q && src_ack || src_update && !busy) begin
-3-
126 // sample data whenever a busy transaction finishes OR
127 // when an update pulse is seen.
128 // TODO: We should add a cover group to test different sync timings
129 // between src_ack and src_update. ie. there can be 3 scenarios:
130 // 1. update one cycle before ack
131 // 2. ack one cycle before update
132 // 3. update / ack on the same cycle
133 // During all 3 cases the read data should be correct
134 src_q <= dst_qs;
==>
135 txn_bits_q <= '0;
136 end
MISSING_ELSE
==>
Branches:
-1- | -2- | -3- | Status | Tests |
1 |
- |
- |
Covered |
T1,T2,T3 |
0 |
1 |
- |
Covered |
T2,T19,T20 |
0 |
0 |
1 |
Covered |
T2,T19,T20 |
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 |
12599233 |
0 |
0 |
T2 |
21894 |
714 |
0 |
0 |
T3 |
63265 |
0 |
0 |
0 |
T4 |
26861 |
0 |
0 |
0 |
T5 |
355835 |
0 |
0 |
0 |
T6 |
296214 |
6015 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
0 |
2474 |
0 |
0 |
T11 |
0 |
3122 |
0 |
0 |
T19 |
183376 |
973 |
0 |
0 |
T20 |
38107 |
1394 |
0 |
0 |
T21 |
0 |
1044 |
0 |
0 |
T22 |
0 |
1500 |
0 |
0 |
T23 |
0 |
1440 |
0 |
0 |
T42 |
0 |
1467 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
12857 |
0 |
0 |
T2 |
21894 |
1 |
0 |
0 |
T3 |
63265 |
0 |
0 |
0 |
T4 |
26861 |
0 |
0 |
0 |
T5 |
355835 |
0 |
0 |
0 |
T6 |
296214 |
4 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
0 |
6 |
0 |
0 |
T11 |
0 |
4 |
0 |
0 |
T19 |
183376 |
1 |
0 |
0 |
T20 |
38107 |
1 |
0 |
0 |
T21 |
0 |
1 |
0 |
0 |
T22 |
0 |
1 |
0 |
0 |
T23 |
0 |
1 |
0 |
0 |
T42 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1832738 |
0 |
0 |
T6 |
296214 |
3340 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1799 |
0 |
0 |
T11 |
329809 |
1466 |
0 |
0 |
T12 |
0 |
133 |
0 |
0 |
T13 |
0 |
728 |
0 |
0 |
T14 |
0 |
337 |
0 |
0 |
T15 |
0 |
176 |
0 |
0 |
T16 |
0 |
374 |
0 |
0 |
T17 |
0 |
236 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1450 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1989 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
4 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1744640 |
0 |
0 |
T6 |
296214 |
3311 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1323 |
0 |
0 |
T11 |
329809 |
1462 |
0 |
0 |
T12 |
0 |
131 |
0 |
0 |
T13 |
0 |
352 |
0 |
0 |
T14 |
0 |
320 |
0 |
0 |
T15 |
0 |
172 |
0 |
0 |
T16 |
0 |
352 |
0 |
0 |
T17 |
0 |
229 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1448 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1866 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1686992 |
0 |
0 |
T6 |
296214 |
3297 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1310 |
0 |
0 |
T11 |
329809 |
1458 |
0 |
0 |
T12 |
0 |
129 |
0 |
0 |
T13 |
0 |
339 |
0 |
0 |
T14 |
0 |
311 |
0 |
0 |
T15 |
0 |
168 |
0 |
0 |
T16 |
0 |
326 |
0 |
0 |
T17 |
0 |
214 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1442 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1820 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1690197 |
0 |
0 |
T6 |
296214 |
3270 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1285 |
0 |
0 |
T11 |
329809 |
1454 |
0 |
0 |
T12 |
0 |
127 |
0 |
0 |
T13 |
0 |
330 |
0 |
0 |
T14 |
0 |
326 |
0 |
0 |
T15 |
0 |
164 |
0 |
0 |
T16 |
0 |
359 |
0 |
0 |
T17 |
0 |
197 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1434 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1828 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1698040 |
0 |
0 |
T6 |
296214 |
3253 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1264 |
0 |
0 |
T11 |
329809 |
1450 |
0 |
0 |
T12 |
0 |
125 |
0 |
0 |
T13 |
0 |
317 |
0 |
0 |
T14 |
0 |
361 |
0 |
0 |
T15 |
0 |
160 |
0 |
0 |
T16 |
0 |
413 |
0 |
0 |
T17 |
0 |
195 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1427 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1848 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1660360 |
0 |
0 |
T6 |
296214 |
3231 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1241 |
0 |
0 |
T11 |
329809 |
1446 |
0 |
0 |
T12 |
0 |
123 |
0 |
0 |
T13 |
0 |
309 |
0 |
0 |
T14 |
0 |
328 |
0 |
0 |
T15 |
0 |
156 |
0 |
0 |
T16 |
0 |
387 |
0 |
0 |
T17 |
0 |
183 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1424 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1823 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1702086 |
0 |
0 |
T6 |
296214 |
3216 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1219 |
0 |
0 |
T11 |
329809 |
1442 |
0 |
0 |
T12 |
0 |
121 |
0 |
0 |
T13 |
0 |
304 |
0 |
0 |
T14 |
0 |
336 |
0 |
0 |
T15 |
0 |
152 |
0 |
0 |
T16 |
0 |
359 |
0 |
0 |
T17 |
0 |
174 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1413 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1868 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1656989 |
0 |
0 |
T6 |
296214 |
3197 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1198 |
0 |
0 |
T11 |
329809 |
1438 |
0 |
0 |
T12 |
0 |
119 |
0 |
0 |
T13 |
0 |
297 |
0 |
0 |
T14 |
0 |
335 |
0 |
0 |
T15 |
0 |
148 |
0 |
0 |
T16 |
0 |
340 |
0 |
0 |
T17 |
0 |
246 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1402 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1838 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1782490 |
0 |
0 |
T6 |
296214 |
3175 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1619 |
0 |
0 |
T11 |
329809 |
1434 |
0 |
0 |
T12 |
0 |
117 |
0 |
0 |
T13 |
0 |
644 |
0 |
0 |
T14 |
0 |
345 |
0 |
0 |
T15 |
0 |
144 |
0 |
0 |
T16 |
0 |
327 |
0 |
0 |
T17 |
0 |
233 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1391 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1941 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
4 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
2 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1681910 |
0 |
0 |
T6 |
296214 |
3143 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1156 |
0 |
0 |
T11 |
329809 |
1430 |
0 |
0 |
T12 |
0 |
115 |
0 |
0 |
T13 |
0 |
270 |
0 |
0 |
T14 |
0 |
348 |
0 |
0 |
T15 |
0 |
140 |
0 |
0 |
T16 |
0 |
368 |
0 |
0 |
T17 |
0 |
228 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1385 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1855 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1674596 |
0 |
0 |
T6 |
296214 |
3124 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1133 |
0 |
0 |
T11 |
329809 |
1426 |
0 |
0 |
T12 |
0 |
113 |
0 |
0 |
T13 |
0 |
263 |
0 |
0 |
T14 |
0 |
323 |
0 |
0 |
T15 |
0 |
136 |
0 |
0 |
T16 |
0 |
353 |
0 |
0 |
T17 |
0 |
220 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1382 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1848 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1634691 |
0 |
0 |
T6 |
296214 |
3101 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1110 |
0 |
0 |
T11 |
329809 |
1422 |
0 |
0 |
T12 |
0 |
111 |
0 |
0 |
T13 |
0 |
252 |
0 |
0 |
T14 |
0 |
335 |
0 |
0 |
T15 |
0 |
132 |
0 |
0 |
T16 |
0 |
392 |
0 |
0 |
T17 |
0 |
212 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1378 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1810 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1653756 |
0 |
0 |
T6 |
296214 |
3075 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1078 |
0 |
0 |
T11 |
329809 |
1418 |
0 |
0 |
T12 |
0 |
109 |
0 |
0 |
T13 |
0 |
366 |
0 |
0 |
T14 |
0 |
355 |
0 |
0 |
T15 |
0 |
128 |
0 |
0 |
T16 |
0 |
368 |
0 |
0 |
T17 |
0 |
203 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1371 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1846 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1645321 |
0 |
0 |
T6 |
296214 |
3057 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1059 |
0 |
0 |
T11 |
329809 |
1414 |
0 |
0 |
T12 |
0 |
107 |
0 |
0 |
T13 |
0 |
360 |
0 |
0 |
T14 |
0 |
344 |
0 |
0 |
T15 |
0 |
124 |
0 |
0 |
T16 |
0 |
343 |
0 |
0 |
T17 |
0 |
196 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1365 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1837 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1636885 |
0 |
0 |
T6 |
296214 |
3031 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1262 |
0 |
0 |
T11 |
329809 |
1410 |
0 |
0 |
T12 |
0 |
105 |
0 |
0 |
T13 |
0 |
348 |
0 |
0 |
T14 |
0 |
318 |
0 |
0 |
T15 |
0 |
180 |
0 |
0 |
T16 |
0 |
385 |
0 |
0 |
T17 |
0 |
184 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1360 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1854 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1670230 |
0 |
0 |
T6 |
296214 |
3005 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
1353 |
0 |
0 |
T11 |
329809 |
1406 |
0 |
0 |
T12 |
0 |
103 |
0 |
0 |
T13 |
0 |
333 |
0 |
0 |
T14 |
0 |
296 |
0 |
0 |
T15 |
0 |
176 |
0 |
0 |
T16 |
0 |
367 |
0 |
0 |
T17 |
0 |
250 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1349 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1853 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
3 |
0 |
0 |
T11 |
329809 |
2 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T15 |
0 |
2 |
0 |
0 |
T16 |
0 |
2 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T36 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T6 T10 T11
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: T6 T10 T11
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T6 T10 T11
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: T6 T10 T11
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T6 T10 T11
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: T6 T10 T11
135 1/1 txn_bits_q <= '0;
Tests: T6 T10 T11
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 | T6,T10,T11 |
LINE 109
EXPRESSION (src_busy_q & ((!src_ack)))
-----1---- ------2-----
-1- | -2- | Status | Tests |
0 | 1 | Covered | T1,T2,T3 |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 | T6,T10,T11 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T6,T10,T11 |
1 | 1 | Covered | T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
T6,T10,T11 |
0 |
0 |
1 |
Covered |
T6,T10,T11 |
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 |
1246123 |
0 |
0 |
T6 |
296214 |
2913 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
836 |
0 |
0 |
T11 |
329809 |
695 |
0 |
0 |
T12 |
0 |
95 |
0 |
0 |
T13 |
0 |
290 |
0 |
0 |
T14 |
0 |
294 |
0 |
0 |
T17 |
0 |
217 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T34 |
0 |
101 |
0 |
0 |
T45 |
0 |
597 |
0 |
0 |
T46 |
0 |
695 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
1374 |
0 |
0 |
T6 |
296214 |
2 |
0 |
0 |
T7 |
312704 |
0 |
0 |
0 |
T8 |
825111 |
0 |
0 |
0 |
T9 |
90904 |
0 |
0 |
0 |
T10 |
386579 |
2 |
0 |
0 |
T11 |
329809 |
1 |
0 |
0 |
T12 |
0 |
1 |
0 |
0 |
T13 |
0 |
1 |
0 |
0 |
T14 |
0 |
3 |
0 |
0 |
T17 |
0 |
1 |
0 |
0 |
T21 |
26318 |
0 |
0 |
0 |
T22 |
823639 |
0 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T34 |
0 |
1 |
0 |
0 |
T45 |
0 |
3 |
0 |
0 |
T46 |
0 |
1 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
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: T10 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: T10 T12 T13
75 1/1 end else if (src_ack) begin
Tests: T1 T2 T3
76 1/1 src_busy_q <= 1'b0;
Tests: T10 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: T10 T12 T13
124 1/1 txn_bits_q <= {src_we_i, src_re_i, src_regwen_i};
Tests: T10 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: T10 T12 T13
135 1/1 txn_bits_q <= '0;
Tests: T10 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_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 | T10,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 | T10,T12,T13 |
1 | 1 | Covered | T10,T12,T13 |
LINE 123
EXPRESSION (src_wd_i & BitMask)
----1--- ---2---
-1- | -2- | Status | Tests |
0 | - | Covered | T10,T12,T13 |
1 | - | Covered | T10,T12,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 | T10,T12,T13 |
LINE 125
SUB-EXPRESSION (src_busy_q && src_ack)
-----1---- ---2---
-1- | -2- | Status | Tests |
0 | 1 | Not Covered | |
1 | 0 | Covered | T10,T12,T13 |
1 | 1 | Covered | T10,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_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 |
T10,T12,T13 |
0 |
0 |
1 |
Covered |
T10,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 |
T10,T12,T13 |
0 |
0 |
1 |
Covered |
T10,T12,T13 |
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 |
18190530 |
0 |
0 |
T10 |
386579 |
796 |
0 |
0 |
T11 |
329809 |
0 |
0 |
0 |
T12 |
171441 |
316 |
0 |
0 |
T13 |
236299 |
741 |
0 |
0 |
T14 |
210446 |
710 |
0 |
0 |
T15 |
0 |
360 |
0 |
0 |
T16 |
0 |
776 |
0 |
0 |
T17 |
0 |
586 |
0 |
0 |
T18 |
0 |
671 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T37 |
0 |
876 |
0 |
0 |
T38 |
0 |
1970 |
0 |
0 |
T40 |
766469 |
0 |
0 |
0 |
T41 |
117799 |
0 |
0 |
0 |
T42 |
35137 |
0 |
0 |
0 |
DstReqKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
32283660 |
31971724 |
0 |
0 |
T1 |
1148 |
1089 |
0 |
0 |
T2 |
86 |
6 |
0 |
0 |
T3 |
1149 |
1083 |
0 |
0 |
T4 |
670 |
576 |
0 |
0 |
T5 |
717 |
646 |
0 |
0 |
T6 |
1014 |
605 |
0 |
0 |
T7 |
1156 |
1060 |
0 |
0 |
T8 |
6346 |
6263 |
0 |
0 |
T19 |
747 |
7 |
0 |
0 |
T20 |
97 |
5 |
0 |
0 |
SrcAckBusyChk_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
18260 |
0 |
0 |
T10 |
386579 |
2 |
0 |
0 |
T11 |
329809 |
0 |
0 |
0 |
T12 |
171441 |
2 |
0 |
0 |
T13 |
236299 |
2 |
0 |
0 |
T14 |
210446 |
6 |
0 |
0 |
T15 |
0 |
4 |
0 |
0 |
T16 |
0 |
4 |
0 |
0 |
T17 |
0 |
2 |
0 |
0 |
T18 |
0 |
4 |
0 |
0 |
T23 |
409361 |
0 |
0 |
0 |
T24 |
546039 |
0 |
0 |
0 |
T37 |
0 |
2 |
0 |
0 |
T38 |
0 |
13 |
0 |
0 |
T40 |
766469 |
0 |
0 |
0 |
T41 |
117799 |
0 |
0 |
0 |
T42 |
35137 |
0 |
0 |
0 |
SrcBusyKnown_A
Name | Attempts | Real Successes | Failures | Incomplete |
Total |
2147483647 |
2147483647 |
0 |
0 |
T1 |
275894 |
275817 |
0 |
0 |
T2 |
21894 |
21832 |
0 |
0 |
T3 |
63265 |
63201 |
0 |
0 |
T4 |
26861 |
26775 |
0 |
0 |
T5 |
355835 |
355749 |
0 |
0 |
T6 |
296214 |
293221 |
0 |
0 |
T7 |
312704 |
312618 |
0 |
0 |
T8 |
825111 |
825048 |
0 |
0 |
T19 |
183376 |
182666 |
0 |
0 |
T20 |
38107 |
38041 |
0 |
0 |