Unified Coverage Report :: Module Instance :: tb.dut.u_reg.u_ec_rst_ctl_cdc.u_arb

Module Instance : tb.dut.u_reg.u_ec_rst_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
83.33	100.00	66.67

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
97.73	100.00	90.91			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_ec_rst_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_ulp_ac_debounce_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
83.33	100.00	66.67

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
97.73	100.00	90.91			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_ulp_ac_debounce_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_ulp_lid_debounce_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
83.33	100.00	66.67

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
97.73	100.00	90.91			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_ulp_lid_debounce_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_ulp_pwrb_debounce_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
83.33	100.00	66.67

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
97.73	100.00	90.91			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_ulp_pwrb_debounce_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_ulp_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
98.08	100.00	92.31			100.00	100.00	u_ulp_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_wkup_status_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
90.68	92.00	88.10			82.61	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
93.39	95.92	86.96			90.70	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
96.88	100.00	87.50			100.00	100.00	u_wkup_status_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_wr_req.u_dst_update_sync	93.75	100.00	75.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_key_invert_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_key_invert_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_pin_allowed_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_pin_allowed_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_pin_out_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_pin_out_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_pin_out_value_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_pin_out_value_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_key_intr_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_key_intr_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_key_intr_debounce_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
83.33	100.00	66.67

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
97.73	100.00	90.91			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_key_intr_debounce_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_auto_block_debounce_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
83.33	100.00	66.67

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
97.73	100.00	90.91			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_auto_block_debounce_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_auto_block_out_ctl_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_auto_block_out_ctl_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_com_pre_sel_ctl_0_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_com_pre_sel_ctl_0_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_com_pre_sel_ctl_1_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_com_pre_sel_ctl_1_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_com_pre_sel_ctl_2_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_com_pre_sel_ctl_2_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_com_pre_sel_ctl_3_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_com_pre_sel_ctl_3_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_com_pre_det_ctl_0_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_com_pre_det_ctl_0_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Module Instance : tb.dut.u_reg.u_com_pre_det_ctl_1_cdc.u_arb

Instance :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00

Instance's subtree :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
100.00	100.00	100.00			100.00	100.00

Parent :

SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT	NAME
97.73	100.00	90.91			100.00	100.00	u_com_pre_det_ctl_1_cdc

Subtrees :

NAME	SCORE	LINE	COND	TOGGLE	FSM	BRANCH	ASSERT
gen_passthru.u_dst_to_src_ack	100.00	100.00	100.00			100.00	100.00

Line Coverage for Instance : tb.dut.u_reg.u_ec_rst_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T4 T3 T7 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T4 T3 T7 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_ec_rst_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	2	66.67
Logical	3	2	66.67
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Not Covered
1	Covered	T4,T5,T1

Line Coverage for Instance : tb.dut.u_reg.u_ulp_ac_debounce_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T2 T24 T10 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T2 T24 T10 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_ulp_ac_debounce_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	2	66.67
Logical	3	2	66.67
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Not Covered
1	Covered	T4,T5,T1

Line Coverage for Instance : tb.dut.u_reg.u_ulp_lid_debounce_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T2 T24 T10 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T2 T24 T10 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_ulp_lid_debounce_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	2	66.67
Logical	3	2	66.67
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Not Covered
1	Covered	T4,T5,T1

Line Coverage for Instance : tb.dut.u_reg.u_ulp_pwrb_debounce_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T2 T24 T10 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T2 T24 T10 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_ulp_pwrb_debounce_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	2	66.67
Logical	3	2	66.67
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Not Covered
1	Covered	T4,T5,T1

Line Coverage for Instance : tb.dut.u_reg.u_ulp_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T2 T10 T25 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T2 T10 T25 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_ulp_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T2,T10,T25
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T2,T10,T25

Line Coverage for Instance : tb.dut.u_reg.u_wkup_status_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		50	46	92.00
CONT_ASSIGN	100	1	1	100.00
ALWAYS	111	3	3	100.00
ALWAYS	121	6	6	100.00
CONT_ASSIGN	135	1	1	100.00
ALWAYS	139	6	5	83.33
ALWAYS	155	10	9	90.00
CONT_ASSIGN	183	1	1	100.00
ALWAYS	187	19	17	89.47
CONT_ASSIGN	228	1	1	100.00
CONT_ASSIGN	243	1	1	100.00
CONT_ASSIGN	244	1	1	100.00

99                        logic dst_update;
100        1/1            assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
           Tests:       T1 T2 T3 
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111        1/1                if (!rst_dst_ni) begin
           Tests:       T4 T5 T1 
112        1/1                  state_q <= StIdle;
           Tests:       T4 T5 T1 
113                           end else begin
114        1/1                  state_q <= state_d;
           Tests:       T4 T5 T1 
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121        1/1                if (!rst_dst_ni) begin
           Tests:       T4 T5 T1 
122        1/1                  dst_req_q <= '0;
           Tests:       T4 T5 T1 
123        1/1                end else if (dst_req_q && dst_lat_d) begin
           Tests:       T4 T5 T1 
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128        1/1                  dst_req_q <= '0;
           Tests:       T20 T21 T22 
129        1/1                end else if (dst_req_i && !dst_req_q && busy) begin
           Tests:       T4 T5 T1 
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132        1/1                  dst_req_q <= 1'b1;
           Tests:       T20 T21 T22 
133                           end
                        MISSING_ELSE
134                         end
135        1/1              assign dst_req = dst_req_q | dst_req_i;
           Tests:       T2 T10 T19 
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139        1/1                if (!rst_dst_ni) begin
           Tests:       T4 T5 T1 
140        1/1                  dst_qs_o <= ResetVal;
           Tests:       T4 T5 T1 
141        1/1                end else if (dst_lat_d) begin
           Tests:       T4 T5 T1 
142        1/1                  dst_qs_o <= dst_ds_i;
           Tests:       T1 T2 T3 
143        1/1                end else if (dst_lat_q) begin
           Tests:       T4 T5 T1 
144        0/1     ==>          dst_qs_o <= dst_qs_i;
145                           end
                        MISSING_ELSE
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155        1/1                if (!rst_dst_ni) begin
           Tests:       T4 T5 T1 
156        1/1                  id_q <= SelSwReq;
           Tests:       T4 T5 T1 
157        1/1                end else if (dst_update_req && dst_update_ack) begin
           Tests:       T4 T5 T1 
158        1/1                  id_q <= SelSwReq;
           Tests:       T1 T2 T3 
159        1/1                end else if (dst_req && dst_lat_d) begin
           Tests:       T4 T5 T1 
160        1/1                  id_q <= SelSwReq;
           Tests:       T2 T10 T19 
161        1/1                end else if (!dst_req && dst_lat_d) begin
           Tests:       T4 T5 T1 
162        1/1                  id_q <= SelHwReq;
           Tests:       T1 T2 T3 
163        1/1                end else if (dst_lat_q) begin
           Tests:       T4 T5 T1 
164        0/1     ==>          id_q <= SelHwReq;
165                           end
                        MISSING_ELSE
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183        1/1              assign dst_req_o = ~busy & dst_req;
           Tests:       T1 T2 T3 
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187        1/1                state_d = state_q;
           Tests:       T1 T2 T3 
188        1/1                dst_hold_req = '0;
           Tests:       T1 T2 T3 
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192        1/1                dst_lat_q = '0;
           Tests:       T1 T2 T3 
193        1/1                dst_lat_d = '0;
           Tests:       T1 T2 T3 
194                     
195        1/1                busy = 1'b1;
           Tests:       T1 T2 T3 
196                     
197        1/1                unique case (state_q)
           Tests:       T1 T2 T3 
198                             StIdle: begin
199        1/1                    busy = '0;
           Tests:       T1 T2 T3 
200        1/1                    if (dst_req) begin
           Tests:       T1 T2 T3 
201                                 // there's a software issued request for change
202        1/1                      state_d = StWait;
           Tests:       T2 T10 T19 
203        1/1                      dst_lat_d = 1'b1;
           Tests:       T2 T10 T19 
204        1/1                    end else if (dst_update) begin
           Tests:       T1 T2 T3 
205        1/1                      state_d = StWait;
           Tests:       T1 T2 T3 
206        1/1                      dst_lat_d = 1'b1;
           Tests:       T1 T2 T3 
207        1/1                    end else if (dst_qs_o != dst_qs_i) begin
           Tests:       T1 T2 T3 
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210        0/1     ==>              state_d = StWait;
211        0/1     ==>              dst_lat_q = 1'b1;
212                               end
                        MISSING_ELSE
213                             end
214                     
215                             StWait: begin
216        1/1                    dst_hold_req = 1'b1;
           Tests:       T1 T2 T3 
217        1/1                    if (dst_update_ack) begin
           Tests:       T1 T2 T3 
218        1/1                      state_d = StIdle;
           Tests:       T1 T2 T3 
219                               end
                        MISSING_ELSE
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228        1/1              assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
           Tests:       T1 T2 T3 
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243        1/1              assign src_ack_o = src_req & (id_q == SelSwReq);
           Tests:       T4 T5 T1 
244        1/1              assign src_update_o = src_req & (id_q == SelHwReq);
           Tests:       T4 T5 T1 

---

Cond Coverage for Instance : tb.dut.u_reg.u_wkup_status_cdc.u_arb

	Total	Covered	Percent
Conditions	42	37	88.10
Logical	42	37	88.10
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Not Covered
1	0	Covered	T1,T2,T6
1	1	Covered	T1,T2,T3

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T1,T2,T3

 LINE       123
 EXPRESSION (gen_wr_req.dst_req_q && gen_wr_req.dst_lat_d)
             ----------1---------    ----------2---------

-1-	-2-	Status	Tests
0	1	Covered	T1,T2,T3
1	0	Covered	T21,T22,T23
1	1	Covered	T20,T21,T22

 LINE       129
 EXPRESSION (dst_req_i && ((!gen_wr_req.dst_req_q)) && gen_wr_req.busy)
             ----1----    ------------2------------    -------3-------

-1-	-2-	-3-	Status	Tests
0	1	1	Covered	T1,T2,T3
1	0	1	Not Covered
1	1	0	Covered	T2,T10,T19
1	1	1	Covered	T20,T21,T22

 LINE       135
 EXPRESSION (gen_wr_req.dst_req_q | dst_req_i)
             ----------1---------   ----2----

-1-	-2-	Status	Tests
0	0	Covered	T4,T5,T1
0	1	Covered	T2,T10,T19
1	0	Covered	T20,T21,T22

 LINE       157
 EXPRESSION (gen_wr_req.dst_update_req && gen_wr_req.dst_update_ack)
             ------------1------------    ------------2------------

-1-	-2-	Status	Tests
0	1	Not Covered
1	0	Covered	T1,T2,T3
1	1	Covered	T1,T2,T3

 LINE       159
 EXPRESSION (gen_wr_req.dst_req && gen_wr_req.dst_lat_d)
             ---------1--------    ----------2---------

-1-	-2-	Status	Tests
0	1	Covered	T1,T2,T3
1	0	Covered	T21,T22,T23
1	1	Covered	T2,T10,T19

 LINE       161
 EXPRESSION (((!gen_wr_req.dst_req)) && gen_wr_req.dst_lat_d)
             -----------1-----------    ----------2---------

-1-	-2-	Status	Tests	Exclude Annotation
0	1	Excluded		VC_COV_UNR
1	0	Covered	T4,T5,T1
1	1	Covered	T1,T2,T3

 LINE       183
 EXPRESSION (((~gen_wr_req.busy)) & gen_wr_req.dst_req)
             ----------1---------   ---------2--------

-1-	-2-	Status	Tests
0	1	Covered	T20,T21,T22
1	0	Covered	T4,T5,T1
1	1	Covered	T2,T10,T19

 LINE       207
 EXPRESSION (dst_qs_o != dst_qs_i)
            -----------1----------

-1-	Status	Tests
0	Covered	T1,T2,T3
1	Not Covered

 LINE       228
 EXPRESSION (gen_wr_req.dst_hold_req | gen_wr_req.dst_lat_d | gen_wr_req.dst_lat_q)
             -----------1-----------   ----------2---------   ----------3---------

-1-	-2-	-3-	Status	Tests
0	0	0	Covered	T4,T5,T1
0	0	1	Not Covered
0	1	0	Covered	T1,T2,T3
1	0	0	Covered	T1,T2,T3

 LINE       243
 EXPRESSION (gen_wr_req.src_req & (gen_wr_req.id_q == SelSwReq))
             ---------1--------   --------------2--------------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Covered	T1,T2,T3
1	1	Covered	T2,T10,T19

 LINE       243
 SUB-EXPRESSION (gen_wr_req.id_q == SelSwReq)
                --------------1--------------

-1-	Status	Tests
0	Covered	T1,T2,T3
1	Covered	T4,T5,T1

 LINE       244
 EXPRESSION (gen_wr_req.src_req & (gen_wr_req.id_q == SelHwReq))
             ---------1--------   --------------2--------------

-1-	-2-	Status	Tests
0	1	Covered	T1,T2,T3
1	0	Covered	T2,T10,T19
1	1	Covered	T1,T2,T3

 LINE       244
 SUB-EXPRESSION (gen_wr_req.id_q == SelHwReq)
                --------------1--------------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T1,T2,T3

---

Branch Coverage for Instance : tb.dut.u_reg.u_wkup_status_cdc.u_arb

	Line No.	Total	Covered	Percent
Branches		23	19	82.61
IF	111	2	2	100.00
IF	121	4	4	100.00
IF	139	4	3	75.00
IF	155	6	5	83.33
CASE	197	7	5	71.43

111              if (!rst_dst_ni) begin
                 -1-  
112                state_q <= StIdle;
                   ==>
113              end else begin
114                state_q <= state_d;
                   ==>

Branches:

-1-	Status	Tests
1	Covered	T4,T5,T1
0	Covered	T4,T5,T1

121              if (!rst_dst_ni) begin
                 -1-  
122                dst_req_q <= '0;
                   ==>
123              end else if (dst_req_q && dst_lat_d) begin
                          -2-  
124                // if request is held, when the transaction starts,
125                // automatically clear.
126                // dst_lat_d is safe to used here because dst_req_q, if set,
127                // always has priority over other hardware based events.
128                dst_req_q <= '0;
                   ==>
129              end else if (dst_req_i && !dst_req_q && busy) begin
                          -3-  
130                // if destination request arrives when a handshake event
131                // is already ongoing, hold on to request and send later
132                dst_req_q <= 1'b1;
                   ==>
133              end
                 MISSING_ELSE
                 ==>

Branches:

-1-	-2-	-3-	Status	Tests
1	-	-	Covered	T4,T5,T1
0	1	-	Covered	T20,T21,T22
0	0	1	Covered	T20,T21,T22
0	0	0	Covered	T4,T5,T1

139              if (!rst_dst_ni) begin
                 -1-  
140                dst_qs_o <= ResetVal;
                   ==>
141              end else if (dst_lat_d) begin
                          -2-  
142                dst_qs_o <= dst_ds_i;
                   ==>
143              end else if (dst_lat_q) begin
                          -3-  
144                dst_qs_o <= dst_qs_i;
                   ==>
145              end
                 MISSING_ELSE
                 ==>

Branches:

-1-	-2-	-3-	Status	Tests
1	-	-	Covered	T4,T5,T1
0	1	-	Covered	T1,T2,T3
0	0	1	Not Covered
0	0	0	Covered	T4,T5,T1

155              if (!rst_dst_ni) begin
                 -1-  
156                id_q <= SelSwReq;
                   ==>
157              end else if (dst_update_req && dst_update_ack) begin
                          -2-  
158                id_q <= SelSwReq;
                   ==>
159              end else if (dst_req && dst_lat_d) begin
                          -3-  
160                id_q <= SelSwReq;
                   ==>
161              end else if (!dst_req && dst_lat_d) begin
                          -4-  
162                id_q <= SelHwReq;
                   ==>
163              end else if (dst_lat_q) begin
                          -5-  
164                id_q <= SelHwReq;
                   ==>
165              end
                 MISSING_ELSE
                 ==>

Branches:

-1-	-2-	-3-	-4-	-5-	Status	Tests
1	-	-	-	-	Covered	T4,T5,T1
0	1	-	-	-	Covered	T1,T2,T3
0	0	1	-	-	Covered	T2,T10,T19
0	0	0	1	-	Covered	T1,T2,T3
0	0	0	0	1	Not Covered
0	0	0	0	0	Covered	T4,T5,T1

197              unique case (state_q)
                        -1-  
198                StIdle: begin
199                  busy = '0;
200                  if (dst_req) begin
                     -2-  
201                    // there's a software issued request for change
202                    state_d = StWait;
                       ==>
203                    dst_lat_d = 1'b1;
204                  end else if (dst_update) begin
                              -3-  
205                    state_d = StWait;
                       ==>
206                    dst_lat_d = 1'b1;
207                  end else if (dst_qs_o != dst_qs_i) begin
                              -4-  
208                    // there's a direct destination update
209                    // that was blocked by an ongoing transaction
210                    state_d = StWait;
                       ==>
211                    dst_lat_q = 1'b1;
212                  end
                     MISSING_ELSE
                     ==>
213                end
214        
215                StWait: begin
216                  dst_hold_req = 1'b1;
217                  if (dst_update_ack) begin
                     -5-  
218                    state_d = StIdle;
                       ==>
219                  end
                     MISSING_ELSE
                     ==>
220                end
221        
222                default: begin
223                  state_d = StIdle;
                     ==>

Branches:

-1-	-2-	-3-	-4-	-5-	Status	Tests
StIdle	1	-	-	-	Covered	T2,T10,T19
StIdle	0	1	-	-	Covered	T1,T2,T3
StIdle	0	0	1	-	Not Covered
StIdle	0	0	0	-	Covered	T1,T2,T3
StWait	-	-	-	1	Covered	T1,T2,T3
StWait	-	-	-	0	Covered	T1,T2,T3
default	-	-	-	-	Not Covered

---

Assert Coverage for Instance : tb.dut.u_reg.u_wkup_status_cdc.u_arb

	Total	Attempted	Percent	Succeeded/Matched	Percent
Assertions	2	2	100.00	2	100.00
Cover properties	0	0		0
Cover sequences	0	0		0
Total	2	2	100.00	2	100.00

---

Assertion Details

Name	Attempts	Real Successes	Failures	Incomplete
gen_wr_req.DstUpdateReqCheck_A	6902343	557	0	910
gen_wr_req.HwIdSelCheck_A	6902343	557	0	0

gen_wr_req.DstUpdateReqCheck_A

Name	Attempts	Real Successes	Failures	Incomplete
Total	6902343	557	0	910
T1	613	1	0	1
T2	1420	2	0	1
T3	504	1	0	1
T6	0	1	0	0
T7	490	1	0	1
T8	0	1	0	0
T9	0	1	0	0
T10	0	1	0	0
T11	0	1	0	0
T12	0	1	0	0
T13	495	0	0	1
T14	423	0	0	1
T15	639	0	0	1
T16	431	0	0	1
T17	435	0	0	1
T18	403	0	0	1

gen_wr_req.HwIdSelCheck_A

Name	Attempts	Real Successes	Failures	Incomplete
Total	6902343	557	0	0
T1	613	1	0	0
T2	1420	2	0	0
T3	504	1	0	0
T6	0	1	0	0
T7	490	1	0	0
T8	0	1	0	0
T9	0	1	0	0
T10	0	1	0	0
T11	0	1	0	0
T12	0	1	0	0
T13	495	0	0	0
T14	423	0	0	0
T15	639	0	0	0
T16	431	0	0	0
T17	435	0	0	0
T18	403	0	0	0

Line Coverage for Instance : tb.dut.u_reg.u_key_invert_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T13 T26 T27 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T13 T26 T27 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_key_invert_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T13,T26,T27
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T13,T26,T27

Line Coverage for Instance : tb.dut.u_reg.u_pin_allowed_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T5 T13 T28 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T5 T13 T28 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_pin_allowed_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T13,T26,T27
1	Covered	T4,T5,T1

Line Coverage for Instance : tb.dut.u_reg.u_pin_out_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T4 T5 T13 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T4 T5 T13 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_pin_out_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T13,T26,T27
1	Covered	T4,T5,T1

Line Coverage for Instance : tb.dut.u_reg.u_pin_out_value_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T5 T28 T29 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T5 T28 T29 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_pin_out_value_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T5,T28,T29
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T5,T28,T29

Line Coverage for Instance : tb.dut.u_reg.u_key_intr_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T1 T6 T9 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T1 T6 T9 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_key_intr_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T1,T6,T9
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T1,T6,T9

Line Coverage for Instance : tb.dut.u_reg.u_key_intr_debounce_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T4 T1 T3 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T4 T1 T3 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_key_intr_debounce_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	2	66.67
Logical	3	2	66.67
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Not Covered
1	Covered	T4,T5,T1

Line Coverage for Instance : tb.dut.u_reg.u_auto_block_debounce_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T15 T30 T31 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T15 T30 T31 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_auto_block_debounce_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	2	66.67
Logical	3	2	66.67
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T4,T5,T1
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Not Covered
1	Covered	T4,T5,T1

Line Coverage for Instance : tb.dut.u_reg.u_auto_block_out_ctl_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		3	3	100.00
CONT_ASSIGN	100	1	1	100.00
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        1/1            assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
           Tests:       T15 T30 T31 
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T15 T30 T31 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T15 T30 T31 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_auto_block_out_ctl_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T15,T30,T31
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T15,T30,T31

Line Coverage for Instance : tb.dut.u_reg.u_com_pre_sel_ctl_0_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T3 T8 T32 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T3 T8 T32 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_com_pre_sel_ctl_0_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T3,T8,T32
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T3,T8,T32

Line Coverage for Instance : tb.dut.u_reg.u_com_pre_sel_ctl_1_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T33 T34 T35 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T33 T34 T35 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_com_pre_sel_ctl_1_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T33,T34,T35
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T33,T34,T35

Line Coverage for Instance : tb.dut.u_reg.u_com_pre_sel_ctl_2_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T33 T34 T35 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T33 T34 T35 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_com_pre_sel_ctl_2_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T33,T34,T35
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T33,T34,T35

Line Coverage for Instance : tb.dut.u_reg.u_com_pre_sel_ctl_3_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T33 T34 T35 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T33 T34 T35 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_com_pre_sel_ctl_3_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T33,T34,T35
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T33,T34,T35

Line Coverage for Instance : tb.dut.u_reg.u_com_pre_det_ctl_0_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T3 T8 T32 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T3 T8 T32 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_com_pre_det_ctl_0_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T3,T8,T32
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T3,T8,T32

Line Coverage for Instance : tb.dut.u_reg.u_com_pre_det_ctl_1_cdc.u_arb

	Line No.	Total	Covered	Percent
TOTAL		2	2	100.00
CONT_ASSIGN	100	0	0
CONT_ASSIGN	283	1	1	100.00
CONT_ASSIGN	284	1	1	100.00
CONT_ASSIGN	299	0	0

99                        logic dst_update;
100        unreachable    assign dst_update = dst_update_i & (dst_qs_o != dst_ds_i);
101                     
102                       if (DstWrReq) begin : gen_wr_req
103                         logic dst_lat_q;
104                         logic dst_lat_d;
105                         logic dst_update_req;
106                         logic dst_update_ack;
107                         req_sel_e id_q;
108                     
109                         state_e state_q, state_d;
110                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
111                           if (!rst_dst_ni) begin
112                             state_q <= StIdle;
113                           end else begin
114                             state_q <= state_d;
115                           end
116                         end
117                     
118                         logic busy;
119                         logic dst_req_q, dst_req;
120                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
121                           if (!rst_dst_ni) begin
122                             dst_req_q <= '0;
123                           end else if (dst_req_q && dst_lat_d) begin
124                             // if request is held, when the transaction starts,
125                             // automatically clear.
126                             // dst_lat_d is safe to used here because dst_req_q, if set,
127                             // always has priority over other hardware based events.
128                             dst_req_q <= '0;
129                           end else if (dst_req_i && !dst_req_q && busy) begin
130                             // if destination request arrives when a handshake event
131                             // is already ongoing, hold on to request and send later
132                             dst_req_q <= 1'b1;
133                           end
134                         end
135                         assign dst_req = dst_req_q | dst_req_i;
136                     
137                         // Hold data at the beginning of a transaction
138                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
139                           if (!rst_dst_ni) begin
140                             dst_qs_o <= ResetVal;
141                           end else if (dst_lat_d) begin
142                             dst_qs_o <= dst_ds_i;
143                           end else if (dst_lat_q) begin
144                             dst_qs_o <= dst_qs_i;
145                           end
146                         end
147                     
148                         // Which type of transaction is being ack'd back?
149                         // 0 - software initiated request
150                         // 1 - hardware initiated request
151                         // The id information is used by prim_reg_cdc to disambiguate
152                         // simultaneous updates from software and hardware.
153                         // See scenario 2 case 3 for an example of how this is handled.
154                         always_ff @(posedge clk_dst_i or negedge rst_dst_ni) begin
155                           if (!rst_dst_ni) begin
156                             id_q <= SelSwReq;
157                           end else if (dst_update_req && dst_update_ack) begin
158                             id_q <= SelSwReq;
159                           end else if (dst_req && dst_lat_d) begin
160                             id_q <= SelSwReq;
161                           end else if (!dst_req && dst_lat_d) begin
162                             id_q <= SelHwReq;
163                           end else if (dst_lat_q) begin
164                             id_q <= SelHwReq;
165                           end
166                         end
167                     
168                         // if a destination update is received when the system is idle and there is no
169                         // software side request, hw update must be selected.
170                         `ASSERT(DstUpdateReqCheck_A, ##1 dst_update & !dst_req & !busy |=> id_q == SelHwReq,
171                           clk_dst_i, !rst_dst_ni)
172                     
173                         // if hw select was chosen, then it must be the case there was a destination update
174                         // indication or there was a difference between the transit register and the
175                         // latest incoming value.
176                         `ASSERT(HwIdSelCheck_A, $rose(id_q == SelHwReq) |-> $past(dst_update_i, 1) ||
177                           $past(dst_lat_q, 1),
178                           clk_dst_i, !rst_dst_ni)
179                     
180                     
181                         // send out prim_subreg request only when proceeding
182                         // with software request
183                         assign dst_req_o = ~busy & dst_req;
184                     
185                         logic dst_hold_req;
186                         always_comb begin
187                           state_d = state_q;
188                           dst_hold_req = '0;
189                     
190                           // depending on when the request is received, we
191                           // may latch d or q.
192                           dst_lat_q = '0;
193                           dst_lat_d = '0;
194                     
195                           busy = 1'b1;
196                     
197                           unique case (state_q)
198                             StIdle: begin
199                               busy = '0;
200                               if (dst_req) begin
201                                 // there's a software issued request for change
202                                 state_d = StWait;
203                                 dst_lat_d = 1'b1;
204                               end else if (dst_update) begin
205                                 state_d = StWait;
206                                 dst_lat_d = 1'b1;
207                               end else if (dst_qs_o != dst_qs_i) begin
208                                 // there's a direct destination update
209                                 // that was blocked by an ongoing transaction
210                                 state_d = StWait;
211                                 dst_lat_q = 1'b1;
212                               end
213                             end
214                     
215                             StWait: begin
216                               dst_hold_req = 1'b1;
217                               if (dst_update_ack) begin
218                                 state_d = StIdle;
219                               end
220                             end
221                     
222                             default: begin
223                               state_d = StIdle;
224                             end
225                           endcase // unique case (state_q)
226                         end // always_comb
227                     
228                         assign dst_update_req = dst_hold_req | dst_lat_d | dst_lat_q;
229                         logic src_req;
230                         prim_sync_reqack u_dst_update_sync (
231                           .clk_src_i(clk_dst_i),
232                           .rst_src_ni(rst_dst_ni),
233                           .clk_dst_i(clk_src_i),
234                           .rst_dst_ni(rst_src_ni),
235                           .req_chk_i(1'b1),
236                           .src_req_i(dst_update_req),
237                           .src_ack_o(dst_update_ack),
238                           .dst_req_o(src_req),
239                           // immediate ack
240                           .dst_ack_i(src_req)
241                         );
242                     
243                         assign src_ack_o = src_req & (id_q == SelSwReq);
244                         assign src_update_o = src_req & (id_q == SelHwReq);
245                     
246                         // once hardware makes an update request, we must eventually see an update pulse
247                         `ifdef FPV_ON
248                           `ASSERT(ReqTimeout_A, $rose(id_q == SelHwReq) |-> s_eventually(src_update_o),
249                                   clk_src_i, !rst_src_ni)
250                           // TODO: #14913 check if we can add additional sim assertions.
251                         `endif
252                     
253                         `ifdef FPV_ON
254                           //VCS coverage off
255                           // pragma coverage off
256                     
257                           logic async_flag;
258                           always_ff @(posedge clk_dst_i or negedge rst_dst_ni or posedge src_update_o) begin
259                             if (!rst_dst_ni) begin
260                               async_flag <= '0;
261                             end else if (src_update_o) begin
262                               async_flag <= '0;
263                             end else if (dst_update && !dst_req_o && !busy) begin
264                               async_flag <= 1'b1;
265                             end
266                           end
267                     
268                           //VCS coverage on
269                           // pragma coverage on
270                     
271                           // once hardware makes an update request, we must eventually see an update pulse
272                           // TODO: #14913 check if we can add additional sim assertions.
273                           `ASSERT(UpdateTimeout_A, $rose(async_flag) |-> s_eventually(src_update_o),
274                                   clk_src_i, !rst_src_ni)
275                         `endif
276                     
277                       end else begin : gen_passthru
278                         // when there is no possibility of conflicting HW transactions,
279                         // we can assume that dst_qs_i will only ever take on the value
280                         // that is directly related to the transaction. As a result,
281                         // there is no need to latch further, and the end destination
282                         // can in fact be used as the holding register.
283        1/1              assign dst_qs_o = dst_qs_i;
           Tests:       T33 T34 T35 
284        1/1              assign dst_req_o = dst_req_i;
           Tests:       T33 T34 T35 
285                     
286                         // since there are no hw transactions, src_update_o is always '0
287                         assign src_update_o = '0;
288                     
289                         prim_pulse_sync u_dst_to_src_ack (
290                           .clk_src_i(clk_dst_i),
291                           .rst_src_ni(rst_dst_ni),
292                           .clk_dst_i(clk_src_i),
293                           .rst_dst_ni(rst_src_ni),
294                           .src_pulse_i(dst_req_i),
295                           .dst_pulse_o(src_ack_o)
296                         );
297                     
298                         logic unused_sigs;
299        unreachable      assign unused_sigs = |{dst_ds_i, dst_update};

---

Cond Coverage for Instance : tb.dut.u_reg.u_com_pre_det_ctl_1_cdc.u_arb

	Total	Covered	Percent
Conditions	3	3	100.00
Logical	3	3	100.00
Non-Logical	0	0
Event	0	0

 LINE       100
 EXPRESSION (dst_update_i & (dst_qs_o != dst_ds_i))
             ------1-----   -----------2----------

-1-	-2-	Status	Tests
0	1	Covered	T33,T34,T35
1	0	Unreachable
1	1	Unreachable

 LINE       100
 SUB-EXPRESSION (dst_qs_o != dst_ds_i)
                -----------1----------

-1-	Status	Tests
0	Covered	T4,T5,T1
1	Covered	T33,T34,T35