yosys/passes/sat/clk2fflogic.cc

282 lines
9.2 KiB
C++

/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#include "kernel/yosys.h"
#include "kernel/sigtools.h"
#include "kernel/ffinit.h"
#include "kernel/ff.h"
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
struct Clk2fflogicPass : public Pass {
Clk2fflogicPass() : Pass("clk2fflogic", "convert clocked FFs to generic $ff cells") { }
void help() override
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" clk2fflogic [options] [selection]\n");
log("\n");
log("This command replaces clocked flip-flops with generic $ff cells that use the\n");
log("implicit global clock. This is useful for formal verification of designs with\n");
log("multiple clocks.\n");
log("\n");
}
SigSpec wrap_async_control(Module *module, SigSpec sig, bool polarity) {
Wire *past_sig = module->addWire(NEW_ID, GetSize(sig));
module->addFf(NEW_ID, sig, past_sig);
if (polarity)
sig = module->Or(NEW_ID, sig, past_sig);
else
sig = module->And(NEW_ID, sig, past_sig);
if (polarity)
return sig;
else
return module->Not(NEW_ID, sig);
}
SigSpec wrap_async_control_gate(Module *module, SigSpec sig, bool polarity) {
Wire *past_sig = module->addWire(NEW_ID);
module->addFfGate(NEW_ID, sig, past_sig);
if (polarity)
sig = module->OrGate(NEW_ID, sig, past_sig);
else
sig = module->AndGate(NEW_ID, sig, past_sig);
if (polarity)
return sig;
else
return module->NotGate(NEW_ID, sig);
}
void execute(std::vector<std::string> args, RTLIL::Design *design) override
{
// bool flag_noinit = false;
log_header(design, "Executing CLK2FFLOGIC pass (convert clocked FFs to generic $ff cells).\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
// if (args[argidx] == "-noinit") {
// flag_noinit = true;
// continue;
// }
break;
}
extra_args(args, argidx, design);
for (auto module : design->selected_modules())
{
SigMap sigmap(module);
FfInitVals initvals(&sigmap, module);
for (auto cell : vector<Cell*>(module->selected_cells()))
{
if (cell->type.in(ID($mem)))
{
int abits = cell->getParam(ID::ABITS).as_int();
int width = cell->getParam(ID::WIDTH).as_int();
int rd_ports = cell->getParam(ID::RD_PORTS).as_int();
int wr_ports = cell->getParam(ID::WR_PORTS).as_int();
for (int i = 0; i < rd_ports; i++) {
if (cell->getParam(ID::RD_CLK_ENABLE).extract(i).as_bool())
log_error("Read port %d of memory %s.%s is clocked. This is not supported by \"clk2fflogic\"! "
"Call \"memory\" with -nordff to avoid this error.\n", i, log_id(cell), log_id(module));
}
Const wr_clk_en_param = cell->getParam(ID::WR_CLK_ENABLE);
Const wr_clk_pol_param = cell->getParam(ID::WR_CLK_POLARITY);
SigSpec wr_clk_port = cell->getPort(ID::WR_CLK);
SigSpec wr_en_port = cell->getPort(ID::WR_EN);
SigSpec wr_addr_port = cell->getPort(ID::WR_ADDR);
SigSpec wr_data_port = cell->getPort(ID::WR_DATA);
for (int wport = 0; wport < wr_ports; wport++)
{
bool clken = wr_clk_en_param[wport] == State::S1;
bool clkpol = wr_clk_pol_param[wport] == State::S1;
if (!clken)
continue;
SigBit clk = wr_clk_port[wport];
SigSpec en = wr_en_port.extract(wport*width, width);
SigSpec addr = wr_addr_port.extract(wport*abits, abits);
SigSpec data = wr_data_port.extract(wport*width, width);
log("Modifying write port %d on memory %s.%s: CLK=%s, A=%s, D=%s\n",
wport, log_id(module), log_id(cell), log_signal(clk),
log_signal(addr), log_signal(data));
Wire *past_clk = module->addWire(NEW_ID);
past_clk->attributes[ID::init] = clkpol ? State::S1 : State::S0;
module->addFf(NEW_ID, clk, past_clk);
SigSpec clock_edge_pattern;
if (clkpol) {
clock_edge_pattern.append(State::S0);
clock_edge_pattern.append(State::S1);
} else {
clock_edge_pattern.append(State::S1);
clock_edge_pattern.append(State::S0);
}
SigSpec clock_edge = module->Eqx(NEW_ID, {clk, SigSpec(past_clk)}, clock_edge_pattern);
SigSpec en_q = module->addWire(NEW_ID, GetSize(en));
module->addFf(NEW_ID, en, en_q);
SigSpec addr_q = module->addWire(NEW_ID, GetSize(addr));
module->addFf(NEW_ID, addr, addr_q);
SigSpec data_q = module->addWire(NEW_ID, GetSize(data));
module->addFf(NEW_ID, data, data_q);
wr_clk_port[wport] = State::S0;
wr_en_port.replace(wport*width, module->Mux(NEW_ID, Const(0, GetSize(en_q)), en_q, clock_edge));
wr_addr_port.replace(wport*abits, addr_q);
wr_data_port.replace(wport*width, data_q);
wr_clk_en_param[wport] = State::S0;
wr_clk_pol_param[wport] = State::S0;
}
cell->setParam(ID::WR_CLK_ENABLE, wr_clk_en_param);
cell->setParam(ID::WR_CLK_POLARITY, wr_clk_pol_param);
cell->setPort(ID::WR_CLK, wr_clk_port);
cell->setPort(ID::WR_EN, wr_en_port);
cell->setPort(ID::WR_ADDR, wr_addr_port);
cell->setPort(ID::WR_DATA, wr_data_port);
}
SigSpec qval;
if (RTLIL::builtin_ff_cell_types().count(cell->type)) {
FfData ff(&initvals, cell);
if (ff.has_d && !ff.has_clk && !ff.has_en) {
// Already a $ff or $_FF_ cell.
continue;
}
Wire *past_q = module->addWire(NEW_ID, ff.width);
if (!ff.is_fine) {
module->addFf(NEW_ID, ff.sig_q, past_q);
} else {
module->addFfGate(NEW_ID, ff.sig_q, past_q);
}
if (!ff.val_init.is_fully_undef())
initvals.set_init(past_q, ff.val_init);
if (ff.has_clk) {
ff.unmap_ce_srst(module);
Wire *past_clk = module->addWire(NEW_ID);
initvals.set_init(past_clk, ff.pol_clk ? State::S1 : State::S0);
if (!ff.is_fine)
module->addFf(NEW_ID, ff.sig_clk, past_clk);
else
module->addFfGate(NEW_ID, ff.sig_clk, past_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));
SigSpec clock_edge_pattern;
if (ff.pol_clk) {
clock_edge_pattern.append(State::S0);
clock_edge_pattern.append(State::S1);
} else {
clock_edge_pattern.append(State::S1);
clock_edge_pattern.append(State::S0);
}
SigSpec clock_edge = module->Eqx(NEW_ID, {ff.sig_clk, SigSpec(past_clk)}, clock_edge_pattern);
Wire *past_d = module->addWire(NEW_ID, ff.width);
if (!ff.is_fine)
module->addFf(NEW_ID, ff.sig_d, past_d);
else
module->addFfGate(NEW_ID, ff.sig_d, past_d);
if (!ff.val_init.is_fully_undef())
initvals.set_init(past_d, ff.val_init);
if (!ff.is_fine)
qval = module->Mux(NEW_ID, past_q, past_d, clock_edge);
else
qval = module->MuxGate(NEW_ID, past_q, past_d, clock_edge);
} else if (ff.has_d) {
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_en), log_signal(ff.sig_d), log_signal(ff.sig_q));
SigSpec sig_en = wrap_async_control(module, ff.sig_en, ff.pol_en);
if (!ff.is_fine)
qval = module->Mux(NEW_ID, past_q, ff.sig_d, sig_en);
else
qval = module->MuxGate(NEW_ID, past_q, ff.sig_d, sig_en);
} else {
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));
qval = past_q;
}
if (ff.has_sr) {
SigSpec setval = wrap_async_control(module, ff.sig_set, ff.pol_set);
SigSpec clrval = wrap_async_control(module, ff.sig_clr, ff.pol_clr);
if (!ff.is_fine) {
clrval = module->Not(NEW_ID, clrval);
qval = module->Or(NEW_ID, qval, setval);
module->addAnd(NEW_ID, qval, clrval, ff.sig_q);
} else {
clrval = module->NotGate(NEW_ID, clrval);
qval = module->OrGate(NEW_ID, qval, setval);
module->addAndGate(NEW_ID, qval, clrval, ff.sig_q);
}
} else if (ff.has_arst) {
SigSpec arst = wrap_async_control(module, ff.sig_arst, ff.pol_arst);
if (!ff.is_fine)
module->addMux(NEW_ID, qval, ff.val_arst, arst, ff.sig_q);
else
module->addMuxGate(NEW_ID, qval, ff.val_arst[0], arst, ff.sig_q);
} else {
module->connect(ff.sig_q, qval);
}
initvals.remove_init(ff.sig_q);
module->remove(cell);
continue;
}
}
}
}
} Clk2fflogicPass;
PRIVATE_NAMESPACE_END