nextpnr/machxo2/pack.cc

117 lines
3.8 KiB
C++

/*
* nextpnr -- Next Generation Place and Route
*
* 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 <algorithm>
#include <iterator>
#include <unordered_set>
#include "cells.h"
#include "design_utils.h"
#include "log.h"
#include "util.h"
NEXTPNR_NAMESPACE_BEGIN
// Merge a net into a constant net
static void set_net_constant(const Context *ctx, NetInfo *orig, NetInfo *constnet, bool constval)
{
(void) constval;
orig->driver.cell = nullptr;
for (auto user : orig->users) {
if (user.cell != nullptr) {
CellInfo *uc = user.cell;
if (ctx->verbose)
log_info("%s user %s\n", orig->name.c_str(ctx), uc->name.c_str(ctx));
uc->ports[user.port].net = constnet;
constnet->users.push_back(user);
}
}
orig->users.clear();
}
// Pack constants (based on simple implementation in generic).
// VCC/GND cells provided by nextpnr automatically.
static void pack_constants(Context *ctx)
{
log_info("Packing constants..\n");
std::unique_ptr<CellInfo> const_cell = create_machxo2_cell(ctx, id_FACADE_SLICE, "$PACKER_CONST");
const_cell->params[id_LUT0_INITVAL] = Property(0, 16);
const_cell->params[id_LUT1_INITVAL] = Property(0xFFFF, 16);
std::unique_ptr<NetInfo> gnd_net = std::unique_ptr<NetInfo>(new NetInfo);
gnd_net->name = ctx->id("$PACKER_GND_NET");
gnd_net->driver.cell = const_cell.get();
gnd_net->driver.port = id_F0;
const_cell->ports.at(id_F0).net = gnd_net.get();
std::unique_ptr<NetInfo> vcc_net = std::unique_ptr<NetInfo>(new NetInfo);
vcc_net->name = ctx->id("$PACKER_VCC_NET");
vcc_net->driver.cell = const_cell.get();
vcc_net->driver.port = id_F1;
const_cell->ports.at(id_F1).net = vcc_net.get();
std::vector<IdString> dead_nets;
for (auto net : sorted(ctx->nets)) {
NetInfo *ni = net.second;
if (ni->driver.cell != nullptr && ni->driver.cell->type == ctx->id("GND")) {
IdString drv_cell = ni->driver.cell->name;
set_net_constant(ctx, ni, gnd_net.get(), false);
dead_nets.push_back(net.first);
ctx->cells.erase(drv_cell);
} else if (ni->driver.cell != nullptr && ni->driver.cell->type == ctx->id("VCC")) {
IdString drv_cell = ni->driver.cell->name;
set_net_constant(ctx, ni, vcc_net.get(), true);
dead_nets.push_back(net.first);
ctx->cells.erase(drv_cell);
}
}
ctx->cells[const_cell->name] = std::move(const_cell);
ctx->nets[gnd_net->name] = std::move(gnd_net);
ctx->nets[vcc_net->name] = std::move(vcc_net);
for (auto dn : dead_nets) {
ctx->nets.erase(dn);
}
}
// Main pack function
bool Arch::pack()
{
Context *ctx = getCtx();
log_info("Packing implementation goes here..");
try {
log_break();
pack_constants(ctx);
ctx->settings[ctx->id("pack")] = 1;
ctx->assignArchInfo();
log_info("Checksum: 0x%08x\n", ctx->checksum());
return true;
} catch (log_execution_error_exception) {
return false;
}
}
NEXTPNR_NAMESPACE_END