async2sync, clk2fflogic: Add support for $check and $print cells

This commit is contained in:
Jannis Harder 2024-01-22 18:32:23 +01:00
parent 6c4902313b
commit e1a59ba80b
3 changed files with 197 additions and 69 deletions

View File

@ -41,31 +41,88 @@ struct Async2syncPass : public Pass {
log("reset value in the next cycle regardless of the data-in value at the time of\n");
log("the clock edge.\n");
log("\n");
log(" -nolower\n");
log(" Do not automatically run 'chformal -lower' to lower $check cells.\n");
log("\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) override
{
// bool flag_noinit = false;
bool flag_nolower = false;
log_header(design, "Executing ASYNC2SYNC pass.\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
// if (args[argidx] == "-noinit") {
// flag_noinit = true;
// continue;
// }
if (args[argidx] == "-nolower") {
flag_nolower = true;
continue;
}
break;
}
extra_args(args, argidx, design);
bool have_check_cells = false;
for (auto module : design->selected_modules())
{
SigMap sigmap(module);
FfInitVals initvals(&sigmap, module);
SigBit initstate;
for (auto cell : vector<Cell*>(module->selected_cells()))
{
if (cell->type.in(ID($print), ID($check)))
{
if (cell->type == ID($check))
have_check_cells = true;
bool trg_enable = cell->getParam(ID(TRG_ENABLE)).as_bool();
if (!trg_enable)
continue;
int trg_width = cell->getParam(ID(TRG_WIDTH)).as_int();
if (trg_width > 1)
log_error("$check cell %s with TRG_WIDTH > 1 is not support by async2sync, use clk2fflogic.\n", log_id(cell));
if (trg_width == 0) {
if (initstate == State::S0)
initstate = module->Initstate(NEW_ID);
SigBit sig_en = cell->getPort(ID::EN);
cell->setPort(ID::EN, module->And(NEW_ID, sig_en, initstate));
} else {
SigBit sig_en = cell->getPort(ID::EN);
SigSpec sig_args = cell->getPort(ID::ARGS);
bool trg_polarity = cell->getParam(ID(TRG_POLARITY)).as_bool();
SigBit sig_trg = cell->getPort(ID::TRG);
Wire *sig_en_q = module->addWire(NEW_ID);
Wire *sig_args_q = module->addWire(NEW_ID, GetSize(sig_args));
sig_en_q->attributes.emplace(ID::init, State::S0);
module->addDff(NEW_ID, sig_trg, sig_en, sig_en_q, trg_polarity, cell->get_src_attribute());
module->addDff(NEW_ID, sig_trg, sig_args, sig_args_q, trg_polarity, cell->get_src_attribute());
cell->setPort(ID::EN, sig_en_q);
cell->setPort(ID::ARGS, sig_args_q);
if (cell->type == ID($check)) {
SigBit sig_a = cell->getPort(ID::A);
Wire *sig_a_q = module->addWire(NEW_ID);
sig_a_q->attributes.emplace(ID::init, State::S1);
module->addDff(NEW_ID, sig_trg, sig_a, sig_a_q, trg_polarity, cell->get_src_attribute());
cell->setPort(ID::A, sig_a_q);
}
}
cell->setPort(ID::TRG, SigSpec());
cell->setParam(ID::TRG_ENABLE, false);
cell->setParam(ID::TRG_WIDTH, 0);
cell->setParam(ID::TRG_POLARITY, false);
cell->set_bool_attribute(ID(trg_on_gclk));
continue;
}
if (!RTLIL::builtin_ff_cell_types().count(cell->type))
continue;
@ -273,6 +330,12 @@ struct Async2syncPass : public Pass {
ff.emit();
}
}
if (have_check_cells && !flag_nolower) {
log_push();
Pass::call(design, "chformal -lower");
log_pop();
}
}
} Async2syncPass;

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@ -48,6 +48,9 @@ struct Clk2fflogicPass : public Pass {
log("reset value in the next cycle regardless of the data-in value at the time of\n");
log("the clock edge.\n");
log("\n");
log(" -nolower\n");
log(" Do not automatically run 'chformal -lower' to lower $check cells.\n");
log("\n");
}
// Active-high sampled and current value of a level-triggered control signal. Initial sampled values is low/non-asserted.
SampledSig sample_control(Module *module, SigSpec sig, bool polarity, bool is_fine) {
@ -117,21 +120,23 @@ struct Clk2fflogicPass : public Pass {
}
void execute(std::vector<std::string> args, RTLIL::Design *design) override
{
// bool flag_noinit = false;
bool flag_nolower = false;
log_header(design, "Executing CLK2FFLOGIC pass (convert clocked FFs to generic $ff cells).\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
// if (args[argidx] == "-noinit") {
// flag_noinit = true;
// continue;
// }
if (args[argidx] == "-nolower") {
flag_nolower = true;
continue;
}
break;
}
extra_args(args, argidx, design);
bool have_check_cells = false;
for (auto module : design->selected_modules())
{
SigMap sigmap(module);
@ -194,79 +199,137 @@ struct Clk2fflogicPass : public Pass {
mem.emit();
}
SigBit initstate;
for (auto cell : vector<Cell*>(module->selected_cells()))
{
SigSpec qval;
if (RTLIL::builtin_ff_cell_types().count(cell->type)) {
FfData ff(&initvals, cell);
if (cell->type.in(ID($print), ID($check)))
{
if (cell->type == ID($check))
have_check_cells = true;
if (ff.has_gclk) {
// Already a $ff or $_FF_ cell.
bool trg_enable = cell->getParam(ID(TRG_ENABLE)).as_bool();
if (!trg_enable)
continue;
}
if (ff.has_clk) {
log("Replacing %s.%s (%s): CLK=%s, D=%s, Q=%s\n",
log_id(module), log_id(cell), log_id(cell->type),
log_signal(ff.sig_clk), log_signal(ff.sig_d), log_signal(ff.sig_q));
} else if (ff.has_aload) {
log("Replacing %s.%s (%s): EN=%s, D=%s, Q=%s\n",
log_id(module), log_id(cell), log_id(cell->type),
log_signal(ff.sig_aload), log_signal(ff.sig_ad), log_signal(ff.sig_q));
int trg_width = cell->getParam(ID(TRG_WIDTH)).as_int();
if (trg_width == 0) {
if (initstate == State::S0)
initstate = module->Initstate(NEW_ID);
SigBit sig_en = cell->getPort(ID::EN);
cell->setPort(ID::EN, module->And(NEW_ID, sig_en, initstate));
} else {
// $sr.
log("Replacing %s.%s (%s): SET=%s, CLR=%s, Q=%s\n",
log_id(module), log_id(cell), log_id(cell->type),
log_signal(ff.sig_set), log_signal(ff.sig_clr), log_signal(ff.sig_q));
SigBit sig_en = cell->getPort(ID::EN);
SigSpec sig_args = cell->getPort(ID::ARGS);
Const trg_polarity = cell->getParam(ID(TRG_POLARITY));
SigSpec sig_trg = cell->getPort(ID::TRG);
SigSpec sig_trg_sampled;
for (auto const &bit : sig_trg)
sig_trg_sampled.append(sample_control_edge(module, bit, trg_polarity[GetSize(sig_trg_sampled)] == State::S1, false));
SigSpec sig_args_sampled = sample_data(module, sig_args, Const(State::S0, GetSize(sig_args)), false, false).sampled;
SigBit sig_en_sampled = sample_data(module, sig_en, State::S0, false, false).sampled;
SigBit sig_trg_combined = module->ReduceOr(NEW_ID, sig_trg_sampled);
cell->setPort(ID::EN, module->And(NEW_ID, sig_en_sampled, sig_trg_combined));
cell->setPort(ID::ARGS, sig_args_sampled);
if (cell->type == ID($check)) {
SigBit sig_a_sampled = sample_data(module, sig_en, State::S1, false, false).sampled;
cell->setPort(ID::A, sig_a_sampled);
}
}
ff.remove();
cell->setPort(ID::TRG, SigSpec());
if (ff.has_clk)
ff.unmap_ce_srst();
cell->setParam(ID::TRG_ENABLE, false);
cell->setParam(ID::TRG_WIDTH, 0);
cell->setParam(ID::TRG_POLARITY, false);
cell->set_bool_attribute(ID(trg_on_gclk));
auto next_q = sample_data(module, ff.sig_q, ff.val_init, ff.is_fine, true).sampled;
if (ff.has_clk) {
// The init value for the sampled d is never used, so we can set it to fixed zero, reducing uninit'd FFs
auto sampled_d = sample_data(module, ff.sig_d, RTLIL::Const(State::S0, ff.width), ff.is_fine);
auto clk_edge = sample_control_edge(module, ff.sig_clk, ff.pol_clk, ff.is_fine);
next_q = mux(module, next_q, sampled_d.sampled, clk_edge, ff.is_fine);
}
SampledSig sampled_aload, sampled_ad, sampled_set, sampled_clr, sampled_arst;
// The check for a constant sig_aload is also done by opt_dff, but when using verific and running
// clk2fflogic before opt_dff (which does more and possibly unwanted optimizations) this check avoids
// generating a lot of extra logic.
bool has_nonconst_aload = ff.has_aload && ff.sig_aload != (ff.pol_aload ? State::S0 : State::S1);
if (has_nonconst_aload) {
sampled_aload = sample_control(module, ff.sig_aload, ff.pol_aload, ff.is_fine);
// The init value for the sampled ad is never used, so we can set it to fixed zero, reducing uninit'd FFs
sampled_ad = sample_data(module, ff.sig_ad, RTLIL::Const(State::S0, ff.width), ff.is_fine);
}
if (ff.has_sr) {
sampled_set = sample_control(module, ff.sig_set, ff.pol_set, ff.is_fine);
sampled_clr = sample_control(module, ff.sig_clr, ff.pol_clr, ff.is_fine);
}
if (ff.has_arst)
sampled_arst = sample_control(module, ff.sig_arst, ff.pol_arst, ff.is_fine);
// First perform updates using _only_ sampled values, then again using _only_ current values. Unlike the previous
// implementation, this approach correctly handles all the cases of multiple signals changing simultaneously.
for (int current = 0; current < 2; current++) {
if (has_nonconst_aload)
next_q = mux(module, next_q, sampled_ad[current], sampled_aload[current], ff.is_fine);
if (ff.has_sr)
next_q = bitwise_sr(module, next_q, sampled_set[current], sampled_clr[current], ff.is_fine);
if (ff.has_arst)
next_q = mux(module, next_q, ff.val_arst, sampled_arst[current], ff.is_fine);
}
module->connect(ff.sig_q, next_q);
continue;
}
if (!RTLIL::builtin_ff_cell_types().count(cell->type))
continue;
FfData ff(&initvals, cell);
if (ff.has_gclk) {
// Already a $ff or $_FF_ cell.
continue;
}
if (ff.has_clk) {
log("Replacing %s.%s (%s): CLK=%s, D=%s, Q=%s\n",
log_id(module), log_id(cell), log_id(cell->type),
log_signal(ff.sig_clk), log_signal(ff.sig_d), log_signal(ff.sig_q));
} else if (ff.has_aload) {
log("Replacing %s.%s (%s): EN=%s, D=%s, Q=%s\n",
log_id(module), log_id(cell), log_id(cell->type),
log_signal(ff.sig_aload), log_signal(ff.sig_ad), log_signal(ff.sig_q));
} else {
// $sr.
log("Replacing %s.%s (%s): SET=%s, CLR=%s, Q=%s\n",
log_id(module), log_id(cell), log_id(cell->type),
log_signal(ff.sig_set), log_signal(ff.sig_clr), log_signal(ff.sig_q));
}
ff.remove();
if (ff.has_clk)
ff.unmap_ce_srst();
auto next_q = sample_data(module, ff.sig_q, ff.val_init, ff.is_fine, true).sampled;
if (ff.has_clk) {
// The init value for the sampled d is never used, so we can set it to fixed zero, reducing uninit'd FFs
auto sampled_d = sample_data(module, ff.sig_d, RTLIL::Const(State::S0, ff.width), ff.is_fine);
auto clk_edge = sample_control_edge(module, ff.sig_clk, ff.pol_clk, ff.is_fine);
next_q = mux(module, next_q, sampled_d.sampled, clk_edge, ff.is_fine);
}
SampledSig sampled_aload, sampled_ad, sampled_set, sampled_clr, sampled_arst;
// The check for a constant sig_aload is also done by opt_dff, but when using verific and running
// clk2fflogic before opt_dff (which does more and possibly unwanted optimizations) this check avoids
// generating a lot of extra logic.
bool has_nonconst_aload = ff.has_aload && ff.sig_aload != (ff.pol_aload ? State::S0 : State::S1);
if (has_nonconst_aload) {
sampled_aload = sample_control(module, ff.sig_aload, ff.pol_aload, ff.is_fine);
// The init value for the sampled ad is never used, so we can set it to fixed zero, reducing uninit'd FFs
sampled_ad = sample_data(module, ff.sig_ad, RTLIL::Const(State::S0, ff.width), ff.is_fine);
}
if (ff.has_sr) {
sampled_set = sample_control(module, ff.sig_set, ff.pol_set, ff.is_fine);
sampled_clr = sample_control(module, ff.sig_clr, ff.pol_clr, ff.is_fine);
}
if (ff.has_arst)
sampled_arst = sample_control(module, ff.sig_arst, ff.pol_arst, ff.is_fine);
// First perform updates using _only_ sampled values, then again using _only_ current values. Unlike the previous
// implementation, this approach correctly handles all the cases of multiple signals changing simultaneously.
for (int current = 0; current < 2; current++) {
if (has_nonconst_aload)
next_q = mux(module, next_q, sampled_ad[current], sampled_aload[current], ff.is_fine);
if (ff.has_sr)
next_q = bitwise_sr(module, next_q, sampled_set[current], sampled_clr[current], ff.is_fine);
if (ff.has_arst)
next_q = mux(module, next_q, ff.val_arst, sampled_arst[current], ff.is_fine);
}
module->connect(ff.sig_q, next_q);
}
}
if (have_check_cells && !flag_nolower) {
log_push();
Pass::call(design, "chformal -lower");
log_pop();
}
}
} Clk2fflogicPass;

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@ -13,6 +13,8 @@ EOT
prep -top top
design -save prep
async2sync
select -assert-count 1 t:$cover