123 lines
4.1 KiB
C++
123 lines
4.1 KiB
C++
/*
|
|
* nextpnr -- Next Generation Place and Route
|
|
*
|
|
* Copyright (C) 2018 Clifford Wolf <clifford@clifford.at>
|
|
* Copyright (C) 2018 David Shah <dave@ds0.me>
|
|
*
|
|
* 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 "pack.h"
|
|
#include "cells.h"
|
|
#include "design_utils.h"
|
|
#include "log.h"
|
|
|
|
#include <unordered_set>
|
|
|
|
// Pack LUTs and LUT-FF pairs
|
|
static void pack_lut_lutffs(Design *design)
|
|
{
|
|
std::unordered_set<IdString> packed_cells;
|
|
std::vector<CellInfo *> new_cells;
|
|
for (auto cell : design->cells) {
|
|
CellInfo *ci = cell.second;
|
|
log_info("cell '%s' is of type '%s'\n", ci->name.c_str(),
|
|
ci->type.c_str());
|
|
if (is_lut(ci)) {
|
|
CellInfo *packed = create_ice_cell(design, "ICESTORM_LC",
|
|
std::string(ci->name) + "_LC");
|
|
packed_cells.insert(ci->name);
|
|
new_cells.push_back(packed);
|
|
log_info("packed cell %s into %s\n", ci->name.c_str(),
|
|
packed->name.c_str());
|
|
// See if we can pack into a DFF
|
|
// TODO: LUT cascade
|
|
NetInfo *o = ci->ports.at("O").net;
|
|
CellInfo *dff = net_only_drives(o, is_ff, "D", true);
|
|
if (dff) {
|
|
lut_to_lc(ci, packed, false);
|
|
dff_to_lc(dff, packed, false);
|
|
design->nets.erase(o->name);
|
|
packed_cells.insert(dff->name);
|
|
log_info("packed cell %s into %s\n", dff->name.c_str(),
|
|
packed->name.c_str());
|
|
} else {
|
|
lut_to_lc(ci, packed, true);
|
|
}
|
|
}
|
|
}
|
|
for (auto pcell : packed_cells) {
|
|
design->cells.erase(pcell);
|
|
}
|
|
for (auto ncell : new_cells) {
|
|
design->cells[ncell->name] = ncell;
|
|
}
|
|
}
|
|
|
|
// Pack FFs not packed as LUTFFs
|
|
static void pack_nonlut_ffs(Design *design)
|
|
{
|
|
std::unordered_set<IdString> packed_cells;
|
|
std::vector<CellInfo *> new_cells;
|
|
|
|
for (auto cell : design->cells) {
|
|
CellInfo *ci = cell.second;
|
|
if (is_ff(ci)) {
|
|
CellInfo *packed = create_ice_cell(design, "ICESTORM_LC",
|
|
std::string(ci->name) + "_LC");
|
|
packed_cells.insert(ci->name);
|
|
new_cells.push_back(packed);
|
|
dff_to_lc(ci, packed, true);
|
|
}
|
|
}
|
|
for (auto pcell : packed_cells) {
|
|
design->cells.erase(pcell);
|
|
}
|
|
for (auto ncell : new_cells) {
|
|
design->cells[ncell->name] = ncell;
|
|
}
|
|
}
|
|
|
|
// Pack constants (simple implementation)
|
|
static void pack_constants(Design *design)
|
|
{
|
|
CellInfo *gnd_cell = create_ice_cell(design, "ICESTORM_LC", "$PACKER_GND");
|
|
gnd_cell->attrs["LUT_INIT"] = "0";
|
|
|
|
CellInfo *vcc_cell = create_ice_cell(design, "ICESTORM_LC", "$PACKER_VCC");
|
|
vcc_cell->attrs["LUT_INIT"] = "1";
|
|
|
|
for (auto net : design->nets) {
|
|
NetInfo *ni = net.second;
|
|
if (ni->driver.cell != nullptr && ni->driver.cell->type == "GND") {
|
|
ni->driver.cell = gnd_cell;
|
|
ni->driver.port = "O";
|
|
design->cells[gnd_cell->name] = gnd_cell;
|
|
} else if (ni->driver.cell != nullptr &&
|
|
ni->driver.cell->type == "VCC") {
|
|
ni->driver.cell = vcc_cell;
|
|
ni->driver.port = "O";
|
|
design->cells[vcc_cell->name] = vcc_cell;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Main pack function
|
|
void pack_design(Design *design)
|
|
{
|
|
pack_constants(design);
|
|
pack_lut_lutffs(design);
|
|
pack_nonlut_ffs(design);
|
|
}
|