OpenFPGA/yosys/passes/techmap/dffinit.cc

136 lines
4.3 KiB
C++
Raw Normal View History

/*
* 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 DffinitPass : public Pass {
DffinitPass() : Pass("dffinit", "set INIT param on FF cells") { }
virtual void help()
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" dffinit [options] [selection]\n");
log("\n");
log("This pass sets an FF cell parameter to the the initial value of the net it\n");
log("drives. (This is primarily used in FPGA flows.)\n");
log("\n");
log(" -ff <cell_name> <output_port> <init_param>\n");
log(" operate on the specified cell type. this option can be used\n");
log(" multiple times.\n");
log("\n");
}
virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
{
log_header(design, "Executing DFFINIT pass (set INIT param on FF cells).\n");
dict<IdString, dict<IdString, IdString>> ff_types;
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++) {
if (args[argidx] == "-ff" && argidx+3 < args.size()) {
IdString cell_name = RTLIL::escape_id(args[++argidx]);
IdString output_port = RTLIL::escape_id(args[++argidx]);
IdString init_param = RTLIL::escape_id(args[++argidx]);
ff_types[cell_name][output_port] = init_param;
continue;
}
break;
}
extra_args(args, argidx, design);
for (auto module : design->selected_modules())
{
SigMap sigmap(module);
dict<SigBit, State> init_bits;
pool<SigBit> cleanup_bits;
pool<SigBit> used_bits;
for (auto wire : module->selected_wires()) {
if (wire->attributes.count("\\init")) {
Const value = wire->attributes.at("\\init");
for (int i = 0; i < min(GetSize(value), GetSize(wire)); i++)
init_bits[sigmap(SigBit(wire, i))] = value[i];
}
if (wire->port_output)
for (auto bit : sigmap(wire))
used_bits.insert(bit);
}
for (auto cell : module->selected_cells())
{
for (auto it : cell->connections())
if (!cell->known() || cell->input(it.first))
for (auto bit : sigmap(it.second))
used_bits.insert(bit);
if (ff_types.count(cell->type) == 0)
continue;
for (auto &it : ff_types[cell->type])
{
if (!cell->hasPort(it.first))
continue;
SigSpec sig = sigmap(cell->getPort(it.first));
Const value;
if (cell->hasParam(it.second))
value = cell->getParam(it.second);
for (int i = 0; i < GetSize(sig); i++) {
if (init_bits.count(sig[i]) == 0)
continue;
while (GetSize(value.bits) <= i)
value.bits.push_back(State::S0);
value.bits[i] = init_bits.at(sig[i]);
cleanup_bits.insert(sig[i]);
}
log("Setting %s.%s.%s (port=%s, net=%s) to %s.\n", log_id(module), log_id(cell), log_id(it.second),
log_id(it.first), log_signal(sig), log_signal(value));
cell->setParam(it.second, value);
}
}
for (auto wire : module->selected_wires())
if (wire->attributes.count("\\init")) {
Const &value = wire->attributes.at("\\init");
bool do_cleanup = true;
for (int i = 0; i < min(GetSize(value), GetSize(wire)); i++) {
SigBit bit = sigmap(SigBit(wire, i));
if (cleanup_bits.count(bit) || !used_bits.count(bit))
value[i] = State::Sx;
else if (value[i] != State::Sx)
do_cleanup = false;
}
if (do_cleanup) {
log("Removing init attribute from wire %s.%s.\n", log_id(module), log_id(wire));
wire->attributes.erase("\\init");
}
}
}
}
} DffinitPass;
PRIVATE_NAMESPACE_END