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|
/*
* nextpnr -- Next Generation Place and Route
*
* Copyright (C) 2018 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 <boost/optional.hpp>
#include <iterator>
#include <unordered_set>
#include "cells.h"
#include "chain_utils.h"
#include "design_utils.h"
#include "log.h"
#include "util.h"
NEXTPNR_NAMESPACE_BEGIN
static bool is_nextpnr_iob(Context *ctx, CellInfo *cell)
{
return cell->type == ctx->id("$nextpnr_ibuf") || cell->type == ctx->id("$nextpnr_obuf") ||
cell->type == ctx->id("$nextpnr_iobuf");
}
class Ecp5Packer
{
public:
Ecp5Packer(Context *ctx) : ctx(ctx){};
private:
// Process the contents of packed_cells and new_cells
void flush_cells()
{
for (auto pcell : packed_cells) {
ctx->cells.erase(pcell);
}
for (auto &ncell : new_cells) {
ctx->cells[ncell->name] = std::move(ncell);
}
packed_cells.clear();
new_cells.clear();
}
// Find FFs associated with LUTs, or LUT expansion muxes
void find_lutff_pairs()
{
log_info("Finding LUTFF pairs...\n");
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_lut(ctx, ci) || is_pfumx(ctx, ci) || is_l6mux(ctx, ci)) {
NetInfo *znet = ci->ports.at(ctx->id("Z")).net;
if (znet != nullptr) {
CellInfo *ff = net_only_drives(ctx, znet, is_ff, ctx->id("DI"), false);
if (ff != nullptr) {
lutffPairs[ci->name] = ff->name;
fflutPairs[ff->name] = ci->name;
}
}
}
}
}
const NetInfo *net_or_nullptr(CellInfo *cell, IdString port)
{
auto fnd = cell->ports.find(port);
if (fnd == cell->ports.end())
return nullptr;
else
return fnd->second.net;
}
// Return whether two FFs can be packed together in the same slice
bool can_pack_ffs(CellInfo *ff0, CellInfo *ff1)
{
if (str_or_default(ff0->params, ctx->id("GSR"), "DISABLED") !=
str_or_default(ff1->params, ctx->id("GSR"), "DISABLED"))
return false;
if (str_or_default(ff0->params, ctx->id("SRMODE"), "LSR_OVER_CE") !=
str_or_default(ff1->params, ctx->id("SRMODE"), "LSR_OVER_CE"))
return false;
if (str_or_default(ff0->params, ctx->id("CEMUX"), "1") != str_or_default(ff1->params, ctx->id("CEMUX"), "1"))
return false;
if (str_or_default(ff0->params, ctx->id("LSRMUX"), "LSR") !=
str_or_default(ff1->params, ctx->id("LSRMUX"), "LSR"))
return false;
if (str_or_default(ff0->params, ctx->id("CLKMUX"), "CLK") !=
str_or_default(ff1->params, ctx->id("CLKMUX"), "CLK"))
return false;
if (net_or_nullptr(ff0, ctx->id("CLK")) != net_or_nullptr(ff1, ctx->id("CLK")))
return false;
if (net_or_nullptr(ff0, ctx->id("CE")) != net_or_nullptr(ff1, ctx->id("CE")))
return false;
if (net_or_nullptr(ff0, ctx->id("LSR")) != net_or_nullptr(ff1, ctx->id("LSR")))
return false;
return true;
}
// Return whether or not an FF can be added to a tile (pairing checks must also be done using the fn above)
bool can_add_ff_to_file(const std::vector<CellInfo *> &tile_ffs, CellInfo *ff0)
{
for (const auto &existing : tile_ffs) {
if (net_or_nullptr(existing, ctx->id("CLK")) != net_or_nullptr(ff0, ctx->id("CLK")))
return false;
if (net_or_nullptr(existing, ctx->id("LSR")) != net_or_nullptr(ff0, ctx->id("LSR")))
return false;
if (str_or_default(existing->params, ctx->id("CLKMUX"), "CLK") !=
str_or_default(ff0->params, ctx->id("CLKMUX"), "CLK"))
return false;
if (str_or_default(existing->params, ctx->id("LSRMUX"), "LSR") !=
str_or_default(ff0->params, ctx->id("LSRMUX"), "LSR"))
return false;
if (str_or_default(existing->params, ctx->id("LSRMUX"), "LSR") !=
str_or_default(ff0->params, ctx->id("LSRMUX"), "LSR"))
return false;
}
return true;
}
// Return true if two LUTs can be paired considering FF compatibility
bool can_pack_lutff(IdString lut0, IdString lut1)
{
auto ff0 = lutffPairs.find(lut0), ff1 = lutffPairs.find(lut1);
if (ff0 != lutffPairs.end() && ff1 != lutffPairs.end()) {
return can_pack_ffs(ctx->cells.at(ff0->second).get(), ctx->cells.at(ff1->second).get());
} else {
return true;
}
}
// Find "closely connected" LUTs and pair them together
void pair_luts()
{
log_info("Finding LUT-LUT pairs...\n");
std::unordered_set<IdString> procdLuts;
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_lut(ctx, ci) && procdLuts.find(cell.first) == procdLuts.end()) {
NetInfo *znet = ci->ports.at(ctx->id("Z")).net;
if (znet != nullptr) {
for (auto user : znet->users) {
if (is_lut(ctx, user.cell) && user.cell != ci &&
procdLuts.find(user.cell->name) == procdLuts.end()) {
if (can_pack_lutff(ci->name, user.cell->name)) {
procdLuts.insert(ci->name);
procdLuts.insert(user.cell->name);
lutPairs[ci->name] = user.cell->name;
goto paired;
}
}
}
if (false) {
paired:
continue;
}
}
if (lutffPairs.find(ci->name) != lutffPairs.end()) {
NetInfo *qnet = ctx->cells.at(lutffPairs[ci->name])->ports.at(ctx->id("Q")).net;
if (qnet != nullptr) {
for (auto user : qnet->users) {
if (is_lut(ctx, user.cell) && user.cell != ci &&
procdLuts.find(user.cell->name) == procdLuts.end()) {
if (can_pack_lutff(ci->name, user.cell->name)) {
procdLuts.insert(ci->name);
procdLuts.insert(user.cell->name);
lutPairs[ci->name] = user.cell->name;
goto paired_ff;
}
}
}
if (false) {
paired_ff:
continue;
}
}
}
for (const char *inp : {"A", "B", "C", "D"}) {
NetInfo *innet = ci->ports.at(ctx->id(inp)).net;
if (innet != nullptr && innet->driver.cell != nullptr) {
CellInfo *drv = innet->driver.cell;
if (is_lut(ctx, drv) && drv != ci && innet->driver.port == ctx->id("Z")) {
if (procdLuts.find(drv->name) == procdLuts.end()) {
if (can_pack_lutff(ci->name, drv->name)) {
procdLuts.insert(ci->name);
procdLuts.insert(drv->name);
lutPairs[ci->name] = drv->name;
goto paired_inlut;
}
}
} else if (is_ff(ctx, drv) && innet->driver.port == ctx->id("Q")) {
auto fflut = fflutPairs.find(drv->name);
if (fflut != fflutPairs.end() && fflut->second != ci->name &&
procdLuts.find(fflut->second) == procdLuts.end()) {
if (can_pack_lutff(ci->name, fflut->second)) {
procdLuts.insert(ci->name);
procdLuts.insert(fflut->second);
lutPairs[ci->name] = fflut->second;
goto paired_inlut;
}
}
}
}
}
if (false) {
paired_inlut:
continue;
}
}
}
}
// Simple "packer" to remove nextpnr IOBUFs, this assumes IOBUFs are manually instantiated
void pack_io()
{
log_info("Packing IOs..\n");
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_nextpnr_iob(ctx, ci)) {
CellInfo *trio = nullptr;
if (ci->type == ctx->id("$nextpnr_ibuf") || ci->type == ctx->id("$nextpnr_iobuf")) {
trio = net_only_drives(ctx, ci->ports.at(ctx->id("O")).net, is_trellis_io, ctx->id("B"), true, ci);
} else if (ci->type == ctx->id("$nextpnr_obuf")) {
trio = net_only_drives(ctx, ci->ports.at(ctx->id("I")).net, is_trellis_io, ctx->id("B"), true, ci);
}
if (trio != nullptr) {
// Trivial case, TRELLIS_IO used. Just destroy the net and the
// iobuf
log_info("%s feeds TRELLIS_IO %s, removing %s %s.\n", ci->name.c_str(ctx), trio->name.c_str(ctx),
ci->type.c_str(ctx), ci->name.c_str(ctx));
NetInfo *net = trio->ports.at(ctx->id("B")).net;
if (net != nullptr) {
ctx->nets.erase(net->name);
trio->ports.at(ctx->id("B")).net = nullptr;
}
if (ci->type == ctx->id("$nextpnr_iobuf")) {
NetInfo *net2 = ci->ports.at(ctx->id("I")).net;
if (net2 != nullptr) {
ctx->nets.erase(net2->name);
}
}
} else {
log_error("TRELLIS_IO required on all top level IOs...\n");
}
packed_cells.insert(ci->name);
std::copy(ci->attrs.begin(), ci->attrs.end(), std::inserter(trio->attrs, trio->attrs.begin()));
auto loc_attr = trio->attrs.find(ctx->id("LOC"));
if (loc_attr != trio->attrs.end()) {
std::string pin = loc_attr->second;
BelId pinBel = ctx->getPackagePinBel(pin);
if (pinBel == BelId()) {
log_error("IO pin '%s' constrained to pin '%s', which does not exist for package '%s'.\n",
trio->name.c_str(ctx), pin.c_str(), ctx->args.package.c_str());
} else {
log_info("pin '%s' constrained to Bel '%s'.\n", trio->name.c_str(ctx),
ctx->getBelName(pinBel).c_str(ctx));
}
trio->attrs[ctx->id("BEL")] = ctx->getBelName(pinBel).str(ctx);
}
}
}
flush_cells();
}
// Pass to pack LUT5s into a newly created slice
void pack_lut5s()
{
log_info("Packing LUT5s...\n");
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_pfumx(ctx, ci)) {
std::unique_ptr<CellInfo> packed =
create_ecp5_cell(ctx, ctx->id("TRELLIS_SLICE"), ci->name.str(ctx) + "_SLICE");
NetInfo *f0 = ci->ports.at(ctx->id("BLUT")).net;
if (f0 == nullptr)
log_error("PFUMX '%s' has disconnected port 'BLUT'\n", ci->name.c_str(ctx));
NetInfo *f1 = ci->ports.at(ctx->id("ALUT")).net;
if (f1 == nullptr)
log_error("PFUMX '%s' has disconnected port 'ALUT'\n", ci->name.c_str(ctx));
CellInfo *lut0 = net_driven_by(ctx, f0, is_lut, ctx->id("Z"));
CellInfo *lut1 = net_driven_by(ctx, f1, is_lut, ctx->id("Z"));
if (lut0 == nullptr)
log_error("PFUMX '%s' has BLUT driven by cell other than a LUT\n", ci->name.c_str(ctx));
if (lut1 == nullptr)
log_error("PFUMX '%s' has ALUT driven by cell other than a LUT\n", ci->name.c_str(ctx));
replace_port(lut0, ctx->id("A"), packed.get(), ctx->id("A0"));
replace_port(lut0, ctx->id("B"), packed.get(), ctx->id("B0"));
replace_port(lut0, ctx->id("C"), packed.get(), ctx->id("C0"));
replace_port(lut0, ctx->id("D"), packed.get(), ctx->id("D0"));
replace_port(lut1, ctx->id("A"), packed.get(), ctx->id("A1"));
replace_port(lut1, ctx->id("B"), packed.get(), ctx->id("B1"));
replace_port(lut1, ctx->id("C"), packed.get(), ctx->id("C1"));
replace_port(lut1, ctx->id("D"), packed.get(), ctx->id("D1"));
replace_port(ci, ctx->id("C0"), packed.get(), ctx->id("M0"));
replace_port(ci, ctx->id("Z"), packed.get(), ctx->id("OFX0"));
packed->params[ctx->id("LUT0_INITVAL")] = str_or_default(lut0->params, ctx->id("INIT"), "0");
packed->params[ctx->id("LUT1_INITVAL")] = str_or_default(lut1->params, ctx->id("INIT"), "0");
ctx->nets.erase(f0->name);
ctx->nets.erase(f1->name);
sliceUsage[packed->name].lut0_used = true;
sliceUsage[packed->name].lut1_used = true;
sliceUsage[packed->name].mux5_used = true;
if (lutffPairs.find(ci->name) != lutffPairs.end()) {
CellInfo *ff = ctx->cells.at(lutffPairs[ci->name]).get();
ff_to_slice(ctx, ff, packed.get(), 0, true);
packed_cells.insert(ff->name);
sliceUsage[packed->name].ff0_used = true;
lutffPairs.erase(ci->name);
fflutPairs.erase(ff->name);
}
new_cells.push_back(std::move(packed));
packed_cells.insert(lut0->name);
packed_cells.insert(lut1->name);
packed_cells.insert(ci->name);
}
}
flush_cells();
}
// Create a feed in to the carry chain
CellInfo *make_carry_feed_in(NetInfo *carry, PortRef chain_in)
{
std::unique_ptr<CellInfo> feedin = create_ecp5_cell(ctx, ctx->id("CCU2C"));
feedin->params[ctx->id("INIT0")] = "10"; // LUT4 = 0; LUT2 = A
feedin->params[ctx->id("INIT1")] = "65535";
feedin->params[ctx->id("INJECT1_0")] = "NO";
feedin->params[ctx->id("INJECT1_1")] = "YES";
carry->users.erase(std::remove_if(carry->users.begin(), carry->users.end(),
[chain_in](const PortRef &user) {
return user.port == chain_in.port && user.cell == chain_in.cell;
}),
carry->users.end());
connect_port(ctx, carry, feedin.get(), id_A0);
std::unique_ptr<NetInfo> new_carry(new NetInfo());
new_carry->name = ctx->id(feedin->name.str(ctx) + "$COUT");
connect_port(ctx, new_carry.get(), feedin.get(), ctx->id("COUT"));
connect_port(ctx, new_carry.get(), chain_in.cell, chain_in.port);
CellInfo *feedin_ptr = feedin.get();
new_cells.push_back(std::move(feedin));
IdString new_carry_name = new_carry->name;
ctx->nets[new_carry_name] = std::move(new_carry);
return feedin_ptr;
}
// Create a feed out and loop through from the carry chain
CellInfo *make_carry_feed_out(NetInfo *carry, boost::optional<PortRef> chain_next = boost::optional<PortRef>())
{
std::unique_ptr<CellInfo> feedout = create_ecp5_cell(ctx, ctx->id("CCU2C"));
feedout->params[ctx->id("INIT0")] = "0";
feedout->params[ctx->id("INIT1")] = "10"; // LUT4 = 0; LUT2 = A
feedout->params[ctx->id("INJECT1_0")] = "YES";
feedout->params[ctx->id("INJECT1_1")] = "NO";
PortRef carry_drv = carry->driver;
carry->driver.cell = nullptr;
connect_port(ctx, carry, feedout.get(), ctx->id("S0"));
std::unique_ptr<NetInfo> new_cin(new NetInfo());
new_cin->name = ctx->id(feedout->name.str(ctx) + "$CIN");
new_cin->driver = carry_drv;
carry_drv.cell->ports.at(carry_drv.port).net = new_cin.get();
connect_port(ctx, new_cin.get(), feedout.get(), ctx->id("CIN"));
if (chain_next) {
// Loop back into LUT4_1 for feedthrough
connect_port(ctx, carry, feedout.get(), id_A1);
carry->users.erase(std::remove_if(carry->users.begin(), carry->users.end(),
[chain_next](const PortRef &user) {
return user.port == chain_next->port && user.cell == chain_next->cell;
}),
carry->users.end());
std::unique_ptr<NetInfo> new_cout(new NetInfo());
new_cout->name = ctx->id(feedout->name.str(ctx) + "$COUT");
connect_port(ctx, new_cout.get(), feedout.get(), ctx->id("COUT"));
chain_next->cell->ports[chain_next->port].net = nullptr;
connect_port(ctx, new_cout.get(), chain_next->cell, chain_next->port);
IdString new_cout_name = new_cout->name;
ctx->nets[new_cout_name] = std::move(new_cout);
}
CellInfo *feedout_ptr = feedout.get();
new_cells.push_back(std::move(feedout));
IdString new_cin_name = new_cin->name;
ctx->nets[new_cin_name] = std::move(new_cin);
return feedout_ptr;
}
// Split a carry chain into multiple legal chains
std::vector<CellChain> split_carry_chain(CellChain &carryc)
{
bool start_of_chain = true;
std::vector<CellChain> chains;
const int max_length = (ctx->chip_info->width - 4) * 4 - 2;
auto curr_cell = carryc.cells.begin();
while (curr_cell != carryc.cells.end()) {
CellInfo *cell = *curr_cell;
if (start_of_chain) {
chains.emplace_back();
start_of_chain = false;
if (cell->ports.at(ctx->id("CIN")).net) {
// CIN is not constant and not part of a chain. Must feed in from fabric
PortRef inport;
inport.cell = cell;
inport.port = ctx->id("CIN");
CellInfo *feedin = make_carry_feed_in(cell->ports.at(ctx->id("CIN")).net, inport);
chains.back().cells.push_back(feedin);
}
}
chains.back().cells.push_back(cell);
bool split_chain = int(chains.back().cells.size()) > max_length;
if (split_chain) {
CellInfo *passout = make_carry_feed_out(cell->ports.at(ctx->id("COUT")).net);
chains.back().cells.back() = passout;
start_of_chain = true;
} else {
NetInfo *carry_net = cell->ports.at(ctx->id("COUT")).net;
bool at_end = (curr_cell == carryc.cells.end() - 1);
if (carry_net != nullptr && (carry_net->users.size() > 1 || at_end)) {
boost::optional<PortRef> nextport;
if (!at_end) {
auto next_cell = *(curr_cell + 1);
PortRef nextpr;
nextpr.cell = next_cell;
nextpr.port = ctx->id("CIN");
nextport = nextpr;
}
CellInfo *passout = make_carry_feed_out(cell->ports.at(ctx->id("COUT")).net, nextport);
chains.back().cells.push_back(passout);
}
++curr_cell;
}
}
return chains;
}
// Pack carries and set up appropriate relative constraints
void pack_carries()
{
log_info("Packing carries...\n");
auto chains = find_chains(
ctx, [](const Context *ctx, const CellInfo *cell) { return is_carry(ctx, cell); },
[](const Context *ctx, const CellInfo *cell) {
return net_driven_by(ctx, cell->ports.at(ctx->id("CIN")).net, is_carry, ctx->id("COUT"));
},
[](const Context *ctx, const CellInfo *cell) {
return net_only_drives(ctx, cell->ports.at(ctx->id("COUT")).net, is_carry, ctx->id("CIN"), false);
},
1);
}
// Pack LUTs that have been paired together
void pack_lut_pairs()
{
log_info("Packing paired LUTs into a SLICE...\n");
for (auto pair : lutPairs) {
CellInfo *lut0 = ctx->cells.at(pair.first).get();
CellInfo *lut1 = ctx->cells.at(pair.second).get();
std::unique_ptr<CellInfo> slice =
create_ecp5_cell(ctx, ctx->id("TRELLIS_SLICE"), lut0->name.str(ctx) + "_SLICE");
lut_to_slice(ctx, lut0, slice.get(), 0);
lut_to_slice(ctx, lut1, slice.get(), 1);
auto ff0 = lutffPairs.find(lut0->name);
if (ff0 != lutffPairs.end()) {
ff_to_slice(ctx, ctx->cells.at(ff0->second).get(), slice.get(), 0, true);
packed_cells.insert(ff0->second);
fflutPairs.erase(ff0->second);
lutffPairs.erase(lut0->name);
}
auto ff1 = lutffPairs.find(lut1->name);
if (ff1 != lutffPairs.end()) {
ff_to_slice(ctx, ctx->cells.at(ff1->second).get(), slice.get(), 1, true);
packed_cells.insert(ff1->second);
fflutPairs.erase(ff1->second);
lutffPairs.erase(lut1->name);
}
new_cells.push_back(std::move(slice));
packed_cells.insert(lut0->name);
packed_cells.insert(lut1->name);
}
flush_cells();
}
// Pack single LUTs that weren't paired into their own slice,
// with an optional FF also
void pack_remaining_luts()
{
log_info("Packing unpaired LUTs into a SLICE...\n");
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_lut(ctx, ci)) {
std::unique_ptr<CellInfo> slice =
create_ecp5_cell(ctx, ctx->id("TRELLIS_SLICE"), ci->name.str(ctx) + "_SLICE");
lut_to_slice(ctx, ci, slice.get(), 0);
auto ff = lutffPairs.find(ci->name);
if (ff != lutffPairs.end()) {
ff_to_slice(ctx, ctx->cells.at(ff->second).get(), slice.get(), 0, true);
packed_cells.insert(ff->second);
fflutPairs.erase(ff->second);
lutffPairs.erase(ci->name);
}
new_cells.push_back(std::move(slice));
packed_cells.insert(ci->name);
}
}
flush_cells();
}
// Pack flipflops that weren't paired with a LUT
void pack_remaining_ffs()
{
log_info("Packing unpaired FFs into a SLICE...\n");
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_ff(ctx, ci)) {
std::unique_ptr<CellInfo> slice =
create_ecp5_cell(ctx, ctx->id("TRELLIS_SLICE"), ci->name.str(ctx) + "_SLICE");
ff_to_slice(ctx, ci, slice.get(), 0, false);
new_cells.push_back(std::move(slice));
packed_cells.insert(ci->name);
}
}
flush_cells();
}
void set_lut_input_constant(CellInfo *cell, IdString input, bool value)
{
int index = std::string("ABCD").find(input.str(ctx));
int init = int_or_default(cell->params, ctx->id("INIT"));
int new_init = 0;
for (int i = 0; i < 16; i++) {
if (((i >> index) & 0x1) != value) {
int other_i = (i & (~(1 << index))) | (value << index);
if ((init >> other_i) & 0x1)
new_init |= (1 << i);
} else {
if ((init >> i) & 0x1)
new_init |= (1 << i);
}
}
cell->params[ctx->id("INIT")] = std::to_string(new_init);
cell->ports.at(input).net = nullptr;
}
// Merge a net into a constant net
void set_net_constant(const Context *ctx, NetInfo *orig, NetInfo *constnet, bool 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));
if (is_lut(ctx, uc)) {
set_lut_input_constant(uc, user.port, constval);
} else if (is_ff(ctx, uc) && user.port == ctx->id("CE")) {
uc->params[ctx->id("CEMUX")] = constval ? "1" : "0";
uc->ports[user.port].net = nullptr;
} else if (is_ff(ctx, uc) && user.port == ctx->id("LSR") &&
((!constval && str_or_default(uc->params, ctx->id("LSRMUX"), "LSR") == "LSR") ||
(constval && str_or_default(uc->params, ctx->id("LSRMUX"), "LSR") == "INV"))) {
uc->ports[user.port].net = nullptr;
} else {
uc->ports[user.port].net = constnet;
constnet->users.push_back(user);
}
}
}
orig->users.clear();
}
// Pack constants (simple implementation)
void pack_constants()
{
log_info("Packing constants..\n");
std::unique_ptr<CellInfo> gnd_cell = create_ecp5_cell(ctx, ctx->id("LUT4"), "$PACKER_GND");
gnd_cell->params[ctx->id("INIT")] = "0";
std::unique_ptr<NetInfo> gnd_net = std::unique_ptr<NetInfo>(new NetInfo);
gnd_net->name = ctx->id("$PACKER_GND_NET");
gnd_net->driver.cell = gnd_cell.get();
gnd_net->driver.port = ctx->id("Z");
gnd_cell->ports.at(ctx->id("Z")).net = gnd_net.get();
std::unique_ptr<CellInfo> vcc_cell = create_ecp5_cell(ctx, ctx->id("LUT4"), "$PACKER_VCC");
vcc_cell->params[ctx->id("INIT")] = "65535";
std::unique_ptr<NetInfo> vcc_net = std::unique_ptr<NetInfo>(new NetInfo);
vcc_net->name = ctx->id("$PACKER_VCC_NET");
vcc_net->driver.cell = vcc_cell.get();
vcc_net->driver.port = ctx->id("Z");
vcc_cell->ports.at(ctx->id("Z")).net = vcc_net.get();
std::vector<IdString> dead_nets;
bool gnd_used = false, vcc_used = false;
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);
gnd_used = true;
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);
vcc_used = true;
dead_nets.push_back(net.first);
ctx->cells.erase(drv_cell);
}
}
if (gnd_used) {
ctx->cells[gnd_cell->name] = std::move(gnd_cell);
ctx->nets[gnd_net->name] = std::move(gnd_net);
}
if (vcc_used) {
ctx->cells[vcc_cell->name] = std::move(vcc_cell);
ctx->nets[vcc_net->name] = std::move(vcc_net);
}
for (auto dn : dead_nets) {
ctx->nets.erase(dn);
}
}
public:
void pack()
{
pack_io();
pack_constants();
find_lutff_pairs();
pack_lut5s();
pair_luts();
pack_lut_pairs();
pack_remaining_luts();
pack_remaining_ffs();
}
private:
Context *ctx;
std::unordered_set<IdString> packed_cells;
std::vector<std::unique_ptr<CellInfo>> new_cells;
struct SliceUsage
{
bool lut0_used = false, lut1_used = false;
bool ccu2_used = false, dpram_used = false, ramw_used = false;
bool ff0_used = false, ff1_used = false;
bool mux5_used = false, muxx_used = false;
};
std::unordered_map<IdString, SliceUsage> sliceUsage;
std::unordered_map<IdString, IdString> lutffPairs;
std::unordered_map<IdString, IdString> fflutPairs;
std::unordered_map<IdString, IdString> lutPairs;
};
// Main pack function
bool Arch::pack()
{
Context *ctx = getCtx();
try {
log_break();
Ecp5Packer(ctx).pack();
log_info("Checksum: 0x%08x\n", ctx->checksum());
assignArchInfo();
return true;
} catch (log_execution_error_exception) {
assignArchInfo();
return false;
}
}
void Arch::assignArchInfo()
{
for (auto cell : sorted(cells)) {
CellInfo *ci = cell.second;
if (ci->type == id_TRELLIS_SLICE) {
if (ci->ports.count(id_CLK) && ci->ports[id_CLK].net != nullptr)
ci->sliceInfo.clk_sig = ci->ports[id_CLK].net->name;
else
ci->sliceInfo.clk_sig = IdString();
if (ci->ports.count(id_LSR) && ci->ports[id_LSR].net != nullptr)
ci->sliceInfo.lsr_sig = ci->ports[id_LSR].net->name;
else
ci->sliceInfo.lsr_sig = IdString();
ci->sliceInfo.clkmux = id(str_or_default(ci->params, id_CLKMUX, "CLK"));
ci->sliceInfo.lsrmux = id(str_or_default(ci->params, id_LSRMUX, "LSR"));
ci->sliceInfo.srmode = id(str_or_default(ci->params, id_SRMODE, "LSR_OVER_CE"));
}
}
}
NEXTPNR_NAMESPACE_END
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