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authorRuben Undheim <ruben.undheim@gmail.com>2016-11-03 23:18:00 +0100
committerRuben Undheim <ruben.undheim@gmail.com>2016-11-03 23:18:00 +0100
commitfefe0fc0430f4f173a25e674708aa0f4f0854b31 (patch)
treeadb13b830212c269d58031f900d652f29013d2d7 /passes/sat/clk2fflogic.cc
parent4f096fe65b77435daba019248273e547fa18d167 (diff)
Imported yosys 0.7
Diffstat (limited to 'passes/sat/clk2fflogic.cc')
-rw-r--r--passes/sat/clk2fflogic.cc226
1 files changed, 226 insertions, 0 deletions
diff --git a/passes/sat/clk2fflogic.cc b/passes/sat/clk2fflogic.cc
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+/*
+ * 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"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+struct Clk2fflogicPass : public Pass {
+ Clk2fflogicPass() : Pass("clk2fflogic", "convert clocked FFs to generic $ff cells") { }
+ virtual void help()
+ {
+ // |---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");
+ }
+ virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+ {
+ // bool flag_noinit = false;
+
+ log_header(design, "Executing CLK2FFLOGIC pass (convert clocked FFs to generic $ff cells).\n");
+
+ size_t argidx;
+ for (argidx = 1; argidx < args.size(); argidx++)
+ {
+ // if (args[argidx] == "-noinit") {
+ // flag_noinit = true;
+ // continue;
+ // }
+ break;
+ }
+ extra_args(args, argidx, design);
+
+ for (auto module : design->selected_modules())
+ {
+ SigMap sigmap(module);
+ dict<SigBit, State> initbits;
+ pool<SigBit> del_initbits;
+
+ for (auto wire : module->wires())
+ if (wire->attributes.count("\\init") > 0)
+ {
+ Const initval = wire->attributes.at("\\init");
+ SigSpec initsig = sigmap(wire);
+
+ for (int i = 0; i < GetSize(initval) && i < GetSize(initsig); i++)
+ if (initval[i] == State::S0 || initval[i] == State::S1)
+ initbits[initsig[i]] = initval[i];
+ }
+
+ for (auto cell : vector<Cell*>(module->selected_cells()))
+ {
+ if (cell->type.in("$dlatch"))
+ {
+ bool enpol = cell->parameters["\\EN_POLARITY"].as_bool();
+
+ SigSpec sig_en = cell->getPort("\\EN");
+ SigSpec sig_d = cell->getPort("\\D");
+ SigSpec sig_q = cell->getPort("\\Q");
+
+ log("Replacing %s.%s (%s): EN=%s, D=%s, Q=%s\n",
+ log_id(module), log_id(cell), log_id(cell->type),
+ log_signal(sig_en), log_signal(sig_d), log_signal(sig_q));
+
+ Wire *past_q = module->addWire(NEW_ID, GetSize(sig_q));
+ module->addFf(NEW_ID, sig_q, past_q);
+
+ if (enpol)
+ module->addMux(NEW_ID, past_q, sig_d, sig_en, sig_q);
+ else
+ module->addMux(NEW_ID, sig_d, past_q, sig_en, sig_q);
+
+ Const initval;
+ bool assign_initval = false;
+ for (int i = 0; i < GetSize(sig_d); i++) {
+ SigBit qbit = sigmap(sig_q[i]);
+ if (initbits.count(qbit)) {
+ initval.bits.push_back(initbits.at(qbit));
+ del_initbits.insert(qbit);
+ } else
+ initval.bits.push_back(State::Sx);
+ if (initval.bits.back() != State::Sx)
+ assign_initval = true;
+ }
+
+ if (assign_initval)
+ past_q->attributes["\\init"] = initval;
+
+ module->remove(cell);
+ continue;
+ }
+
+ if (cell->type.in("$dff", "$adff", "$dffsr"))
+ {
+ bool clkpol = cell->parameters["\\CLK_POLARITY"].as_bool();
+
+ SigSpec clk = cell->getPort("\\CLK");
+ Wire *past_clk = module->addWire(NEW_ID);
+ past_clk->attributes["\\init"] = clkpol ? State::S1 : State::S0;
+ module->addFf(NEW_ID, clk, past_clk);
+
+ SigSpec sig_d = cell->getPort("\\D");
+ SigSpec sig_q = cell->getPort("\\Q");
+
+ log("Replacing %s.%s (%s): CLK=%s, D=%s, Q=%s\n",
+ log_id(module), log_id(cell), log_id(cell->type),
+ log_signal(clk), log_signal(sig_d), log_signal(sig_q));
+
+ SigSpec clock_edge_pattern;
+
+ if (clkpol) {
+ clock_edge_pattern.append_bit(State::S0);
+ clock_edge_pattern.append_bit(State::S1);
+ } else {
+ clock_edge_pattern.append_bit(State::S1);
+ clock_edge_pattern.append_bit(State::S0);
+ }
+
+ SigSpec clock_edge = module->Eqx(NEW_ID, {clk, SigSpec(past_clk)}, clock_edge_pattern);
+
+ Wire *past_d = module->addWire(NEW_ID, GetSize(sig_d));
+ Wire *past_q = module->addWire(NEW_ID, GetSize(sig_q));
+ module->addFf(NEW_ID, sig_d, past_d);
+ module->addFf(NEW_ID, sig_q, past_q);
+
+ if (cell->type == "$adff")
+ {
+ SigSpec arst = cell->getPort("\\ARST");
+ SigSpec qval = module->Mux(NEW_ID, past_q, past_d, clock_edge);
+ Const rstval = cell->parameters["\\ARST_VALUE"];
+
+ if (cell->parameters["\\ARST_POLARITY"].as_bool())
+ module->addMux(NEW_ID, qval, rstval, arst, sig_q);
+ else
+ module->addMux(NEW_ID, rstval, qval, arst, sig_q);
+ }
+ else
+ if (cell->type == "$dffsr")
+ {
+ SigSpec qval = module->Mux(NEW_ID, past_q, past_d, clock_edge);
+ SigSpec setval = cell->getPort("\\SET");
+ SigSpec clrval = cell->getPort("\\CLR");
+
+ if (!cell->parameters["\\SET_POLARITY"].as_bool())
+ setval = module->Not(NEW_ID, setval);
+
+ if (cell->parameters["\\CLR_POLARITY"].as_bool())
+ clrval = module->Not(NEW_ID, clrval);
+
+ qval = module->Or(NEW_ID, qval, setval);
+ module->addAnd(NEW_ID, qval, clrval, sig_q);
+ }
+ else
+ {
+ module->addMux(NEW_ID, past_q, past_d, clock_edge, sig_q);
+ }
+
+ Const initval;
+ bool assign_initval = false;
+ for (int i = 0; i < GetSize(sig_d); i++) {
+ SigBit qbit = sigmap(sig_q[i]);
+ if (initbits.count(qbit)) {
+ initval.bits.push_back(initbits.at(qbit));
+ del_initbits.insert(qbit);
+ } else
+ initval.bits.push_back(State::Sx);
+ if (initval.bits.back() != State::Sx)
+ assign_initval = true;
+ }
+
+ if (assign_initval) {
+ past_d->attributes["\\init"] = initval;
+ past_q->attributes["\\init"] = initval;
+ }
+
+ module->remove(cell);
+ continue;
+ }
+ }
+
+ for (auto wire : module->wires())
+ if (wire->attributes.count("\\init") > 0)
+ {
+ bool delete_initattr = true;
+ Const initval = wire->attributes.at("\\init");
+ SigSpec initsig = sigmap(wire);
+
+ for (int i = 0; i < GetSize(initval) && i < GetSize(initsig); i++)
+ if (del_initbits.count(initsig[i]) > 0)
+ initval[i] = State::Sx;
+ else if (initval[i] != State::Sx)
+ delete_initattr = false;
+
+ if (delete_initattr)
+ wire->attributes.erase("\\init");
+ else
+ wire->attributes.at("\\init") = initval;
+ }
+ }
+
+ }
+} Clk2fflogicPass;
+
+PRIVATE_NAMESPACE_END