yosys/techlibs/ecp5/ecp5_ffinit.cc

199 lines
6.2 KiB
C++

/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
* Copyright (C) 2018-19 David Shah <david@symbioticeda.com>
*
* 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 Ecp5FfinitPass : public Pass {
Ecp5FfinitPass() : Pass("ecp5_ffinit", "ECP5: handle FF init values") { }
void help() YS_OVERRIDE
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" ecp5_ffinit [options] [selection]\n");
log("\n");
log("Remove init values for FF output signals when equal to reset value.\n");
log("If reset is not used, set the reset value to the init value, otherwise\n");
log("unmap out the reset (if not an async reset).\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
{
log_header(design, "Executing ECP5_FFINIT pass (implement FF init values).\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
// if (args[argidx] == "-singleton") {
// singleton_mode = true;
// continue;
// }
break;
}
extra_args(args, argidx, design);
for (auto module : design->selected_modules())
{
log("Handling FF init values in %s.\n", log_id(module));
SigMap sigmap(module);
pool<Wire*> init_wires;
dict<SigBit, State> initbits;
dict<SigBit, SigBit> initbit_to_wire;
pool<SigBit> handled_initbits;
for (auto wire : module->selected_wires())
{
if (wire->attributes.count("\\init") == 0)
continue;
SigSpec wirebits = sigmap(wire);
Const initval = wire->attributes.at("\\init");
init_wires.insert(wire);
for (int i = 0; i < GetSize(wirebits) && i < GetSize(initval); i++)
{
SigBit bit = wirebits[i];
State val = initval[i];
if (val != State::S0 && val != State::S1)
continue;
if (initbits.count(bit)) {
if (initbits.at(bit) != val)
log_error("Conflicting init values for signal %s (%s = %s, %s = %s).\n",
log_signal(bit), log_signal(SigBit(wire, i)), log_signal(val),
log_signal(initbit_to_wire[bit]), log_signal(initbits.at(bit)));
continue;
}
initbits[bit] = val;
initbit_to_wire[bit] = SigBit(wire, i);
}
}
for (auto cell : module->selected_cells())
{
if (cell->type != "\\TRELLIS_FF")
continue;
SigSpec sig_d = cell->getPort("\\DI");
SigSpec sig_q = cell->getPort("\\Q");
SigSpec sig_lsr = cell->getPort("\\LSR");
if (GetSize(sig_d) < 1 || GetSize(sig_q) < 1)
continue;
SigBit bit_d = sigmap(sig_d[0]);
SigBit bit_q = sigmap(sig_q[0]);
std::string regset = "RESET";
if (cell->hasParam("\\REGSET"))
regset = cell->getParam("\\REGSET").decode_string();
State resetState;
if (regset == "SET")
resetState = State::S1;
else if (regset == "RESET")
resetState = State::S0;
else
log_error("FF cell %s has illegal REGSET value %s.\n",
log_id(cell), regset.c_str());
if (!initbits.count(bit_q))
continue;
State val = initbits.at(bit_q);
log("FF init value for cell %s (%s): %s = %c\n", log_id(cell), log_id(cell->type),
log_signal(bit_q), val != State::S0 ? '1' : '0');
// Initval is the same as the reset state. Matches hardware, nowt more to do
if (val == resetState) {
handled_initbits.insert(bit_q);
continue;
}
if (GetSize(sig_lsr) >= 1 && sig_lsr[0] != State::S0) {
std::string srmode = "LSR_OVER_CE";
if (cell->hasParam("\\SRMODE"))
srmode = cell->getParam("\\SRMODE").decode_string();
if (srmode == "ASYNC") {
log("Async reset value %c for FF cell %s inconsistent with init value %c.\n",
resetState != State::S0 ? '1' : '0', log_id(cell), val != State::S0 ? '1' : '0');
} else {
SigBit bit_lsr = sigmap(sig_lsr[0]);
Wire *new_bit_d = module->addWire(NEW_ID);
if (resetState == State::S0) {
module->addAndnotGate(NEW_ID, bit_d, bit_lsr, new_bit_d);
} else {
module->addOrGate(NEW_ID, bit_d, bit_lsr, new_bit_d);
}
cell->setPort("\\DI", new_bit_d);
cell->setPort("\\LSR", State::S0);
if(cell->hasPort("\\CE")) {
std::string cemux = "CE";
if (cell->hasParam("\\CEMUX"))
cemux = cell->getParam("\\CEMUX").decode_string();
SigSpec sig_ce = cell->getPort("\\CE");
if (GetSize(sig_ce) >= 1) {
SigBit bit_ce = sigmap(sig_ce[0]);
Wire *new_bit_ce = module->addWire(NEW_ID);
if (cemux == "INV")
module->addAndnotGate(NEW_ID, bit_ce, bit_lsr, new_bit_ce);
else
module->addOrGate(NEW_ID, bit_ce, bit_lsr, new_bit_ce);
cell->setPort("\\CE", new_bit_ce);
}
}
cell->setParam("\\REGSET", val != State::S0 ? Const("SET") : Const("RESET"));
handled_initbits.insert(bit_q);
}
} else {
cell->setParam("\\REGSET", val != State::S0 ? Const("SET") : Const("RESET"));
handled_initbits.insert(bit_q);
}
}
for (auto wire : init_wires)
{
if (wire->attributes.count("\\init") == 0)
continue;
SigSpec wirebits = sigmap(wire);
Const &initval = wire->attributes.at("\\init");
bool remove_attribute = true;
for (int i = 0; i < GetSize(wirebits) && i < GetSize(initval); i++) {
if (handled_initbits.count(wirebits[i]))
initval[i] = State::Sx;
else if (initval[i] != State::Sx)
remove_attribute = false;
}
if (remove_attribute)
wire->attributes.erase("\\init");
}
}
}
} Ecp5FfinitPass;
PRIVATE_NAMESPACE_END