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|
/*
* nextpnr -- Next Generation Place and Route
*
* Copyright (C) 2018 Clifford Wolf <clifford@symbioticeda.com>
* Copyright (C) 2018 David Shah <david@symbioticeda.com>
* Copyright (C) 2018 Serge Bazanski <q3k@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 "chains.h"
#include "design_utils.h"
#include "log.h"
#include "util.h"
NEXTPNR_NAMESPACE_BEGIN
// Pack LUTs and LUT-FF pairs
static void pack_lut_lutffs(Context *ctx)
{
log_info("Packing LUT-FFs..\n");
std::unordered_set<IdString> packed_cells;
std::vector<std::unique_ptr<CellInfo>> new_cells;
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (ctx->verbose)
log_info("cell '%s' is of type '%s'\n", ci->name.c_str(ctx), ci->type.c_str(ctx));
if (is_lut(ctx, ci)) {
std::unique_ptr<CellInfo> packed = create_ice_cell(ctx, ctx->id("ICESTORM_LC"), ci->name.str(ctx) + "_LC");
std::copy(ci->attrs.begin(), ci->attrs.end(), std::inserter(packed->attrs, packed->attrs.begin()));
packed_cells.insert(ci->name);
if (ctx->verbose)
log_info("packed cell %s into %s\n", ci->name.c_str(ctx), packed->name.c_str(ctx));
// See if we can pack into a DFF
// TODO: LUT cascade
NetInfo *o = ci->ports.at(ctx->id("O")).net;
CellInfo *dff = net_only_drives(ctx, o, is_ff, ctx->id("D"), true);
auto lut_bel = ci->attrs.find(ctx->id("BEL"));
bool packed_dff = false;
if (dff) {
if (ctx->verbose)
log_info("found attached dff %s\n", dff->name.c_str(ctx));
auto dff_bel = dff->attrs.find(ctx->id("BEL"));
if (lut_bel != ci->attrs.end() && dff_bel != dff->attrs.end() && lut_bel->second != dff_bel->second) {
// Locations don't match, can't pack
} else {
lut_to_lc(ctx, ci, packed.get(), false);
dff_to_lc(ctx, dff, packed.get(), false);
ctx->nets.erase(o->name);
if (dff_bel != dff->attrs.end())
packed->attrs[ctx->id("BEL")] = dff_bel->second;
packed_cells.insert(dff->name);
if (ctx->verbose)
log_info("packed cell %s into %s\n", dff->name.c_str(ctx), packed->name.c_str(ctx));
packed_dff = true;
}
}
if (!packed_dff) {
lut_to_lc(ctx, ci, packed.get(), true);
}
new_cells.push_back(std::move(packed));
}
}
for (auto pcell : packed_cells) {
ctx->cells.erase(pcell);
}
for (auto &ncell : new_cells) {
ctx->cells[ncell->name] = std::move(ncell);
}
}
// Pack FFs not packed as LUTFFs
static void pack_nonlut_ffs(Context *ctx)
{
log_info("Packing non-LUT FFs..\n");
std::unordered_set<IdString> packed_cells;
std::vector<std::unique_ptr<CellInfo>> new_cells;
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_ff(ctx, ci)) {
std::unique_ptr<CellInfo> packed =
create_ice_cell(ctx, ctx->id("ICESTORM_LC"), ci->name.str(ctx) + "_DFFLC");
std::copy(ci->attrs.begin(), ci->attrs.end(), std::inserter(packed->attrs, packed->attrs.begin()));
if (ctx->verbose)
log_info("packed cell %s into %s\n", ci->name.c_str(ctx), packed->name.c_str(ctx));
packed_cells.insert(ci->name);
dff_to_lc(ctx, ci, packed.get(), true);
new_cells.push_back(std::move(packed));
}
}
for (auto pcell : packed_cells) {
ctx->cells.erase(pcell);
}
for (auto &ncell : new_cells) {
ctx->cells[ncell->name] = std::move(ncell);
}
}
static bool net_is_constant(const Context *ctx, NetInfo *net, bool &value)
{
if (net == nullptr)
return false;
if (net->name == ctx->id("$PACKER_GND_NET") || net->name == ctx->id("$PACKER_VCC_NET")) {
value = (net->name == ctx->id("$PACKER_VCC_NET"));
return true;
} else {
return false;
}
}
// Pack carry logic
static void pack_carries(Context *ctx)
{
log_info("Packing carries..\n");
std::unordered_set<IdString> exhausted_cells;
std::unordered_set<IdString> packed_cells;
std::vector<std::unique_ptr<CellInfo>> new_cells;
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_carry(ctx, ci)) {
packed_cells.insert(cell.first);
CellInfo *carry_ci_lc;
bool ci_value;
bool ci_const = net_is_constant(ctx, ci->ports.at(ctx->id("CI")).net, ci_value);
if (ci_const) {
carry_ci_lc = nullptr;
} else {
carry_ci_lc = net_only_drives(ctx, ci->ports.at(ctx->id("CI")).net, is_lc, ctx->id("I3"), false);
}
std::set<IdString> i0_matches, i1_matches;
NetInfo *i0_net = ci->ports.at(ctx->id("I0")).net;
NetInfo *i1_net = ci->ports.at(ctx->id("I1")).net;
// Find logic cells connected to both I0 and I1
if (i0_net) {
for (auto usr : i0_net->users) {
if (is_lc(ctx, usr.cell) && usr.port == ctx->id("I1")) {
if (ctx->cells.find(usr.cell->name) != ctx->cells.end() &&
exhausted_cells.find(usr.cell->name) == exhausted_cells.end()) {
// This clause stops us double-packing cells
i0_matches.insert(usr.cell->name);
if (!i1_net && !usr.cell->ports.at(ctx->id("I2")).net) {
// I1 is don't care when disconnected, duplicate I0
i1_matches.insert(usr.cell->name);
}
}
}
}
}
if (i1_net) {
for (auto usr : i1_net->users) {
if (is_lc(ctx, usr.cell) && usr.port == ctx->id("I2")) {
if (ctx->cells.find(usr.cell->name) != ctx->cells.end() &&
exhausted_cells.find(usr.cell->name) == exhausted_cells.end()) {
// This clause stops us double-packing cells
i1_matches.insert(usr.cell->name);
if (!i0_net && !usr.cell->ports.at(ctx->id("I1")).net) {
// I0 is don't care when disconnected, duplicate I1
i0_matches.insert(usr.cell->name);
}
}
}
}
}
std::set<IdString> carry_lcs;
std::set_intersection(i0_matches.begin(), i0_matches.end(), i1_matches.begin(), i1_matches.end(),
std::inserter(carry_lcs, carry_lcs.end()));
CellInfo *carry_lc = nullptr;
if (carry_ci_lc && carry_lcs.find(carry_ci_lc->name) != carry_lcs.end()) {
carry_lc = carry_ci_lc;
} else {
// No LC to pack into matching I0/I1, insert a new one
std::unique_ptr<CellInfo> created_lc =
create_ice_cell(ctx, ctx->id("ICESTORM_LC"), cell.first.str(ctx) + "$CARRY");
carry_lc = created_lc.get();
created_lc->ports.at(ctx->id("I1")).net = i0_net;
if (i0_net) {
PortRef pr;
pr.cell = created_lc.get();
pr.port = ctx->id("I1");
i0_net->users.push_back(pr);
}
created_lc->ports.at(ctx->id("I2")).net = i1_net;
if (i1_net) {
PortRef pr;
pr.cell = created_lc.get();
pr.port = ctx->id("I2");
i1_net->users.push_back(pr);
}
new_cells.push_back(std::move(created_lc));
}
carry_lc->params[ctx->id("CARRY_ENABLE")] = "1";
replace_port(ci, ctx->id("CI"), carry_lc, ctx->id("CIN"));
replace_port(ci, ctx->id("CO"), carry_lc, ctx->id("COUT"));
if (i0_net) {
auto &i0_usrs = i0_net->users;
i0_usrs.erase(std::remove_if(i0_usrs.begin(), i0_usrs.end(), [ci, ctx](const PortRef &pr) {
return pr.cell == ci && pr.port == ctx->id("I0");
}));
}
if (i1_net) {
auto &i1_usrs = i1_net->users;
i1_usrs.erase(std::remove_if(i1_usrs.begin(), i1_usrs.end(), [ci, ctx](const PortRef &pr) {
return pr.cell == ci && pr.port == ctx->id("I1");
}));
}
// Check for constant driver on CIN
if (carry_lc->ports.at(ctx->id("CIN")).net != nullptr) {
IdString cin_net = carry_lc->ports.at(ctx->id("CIN")).net->name;
if (cin_net == ctx->id("$PACKER_GND_NET") || cin_net == ctx->id("$PACKER_VCC_NET")) {
carry_lc->params[ctx->id("CIN_CONST")] = "1";
carry_lc->params[ctx->id("CIN_SET")] = cin_net == ctx->id("$PACKER_VCC_NET") ? "1" : "0";
carry_lc->ports.at(ctx->id("CIN")).net = nullptr;
auto &cin_users = ctx->nets.at(cin_net)->users;
cin_users.erase(
std::remove_if(cin_users.begin(), cin_users.end(), [carry_lc, ctx](const PortRef &pr) {
return pr.cell == carry_lc && pr.port == ctx->id("CIN");
}));
}
}
exhausted_cells.insert(carry_lc->name);
}
}
for (auto pcell : packed_cells) {
ctx->cells.erase(pcell);
}
for (auto &ncell : new_cells) {
ctx->cells[ncell->name] = std::move(ncell);
}
}
// "Pack" RAMs
static void pack_ram(Context *ctx)
{
log_info("Packing RAMs..\n");
std::unordered_set<IdString> packed_cells;
std::vector<std::unique_ptr<CellInfo>> new_cells;
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_ram(ctx, ci)) {
std::unique_ptr<CellInfo> packed =
create_ice_cell(ctx, ctx->id("ICESTORM_RAM"), ci->name.str(ctx) + "_RAM");
packed_cells.insert(ci->name);
for (auto param : ci->params)
packed->params[param.first] = param.second;
packed->params[ctx->id("NEG_CLK_W")] =
std::to_string(ci->type == ctx->id("SB_RAM40_4KNW") || ci->type == ctx->id("SB_RAM40_4KNRNW"));
packed->params[ctx->id("NEG_CLK_R")] =
std::to_string(ci->type == ctx->id("SB_RAM40_4KNR") || ci->type == ctx->id("SB_RAM40_4KNRNW"));
packed->type = ctx->id("ICESTORM_RAM");
for (auto port : ci->ports) {
PortInfo &pi = port.second;
std::string newname = pi.name.str(ctx);
size_t bpos = newname.find('[');
if (bpos != std::string::npos) {
newname = newname.substr(0, bpos) + "_" + newname.substr(bpos + 1, (newname.size() - bpos) - 2);
}
if (pi.name == ctx->id("RCLKN"))
newname = "RCLK";
else if (pi.name == ctx->id("WCLKN"))
newname = "WCLK";
replace_port(ci, ctx->id(pi.name.c_str(ctx)), packed.get(), ctx->id(newname));
}
new_cells.push_back(std::move(packed));
}
}
for (auto pcell : packed_cells) {
ctx->cells.erase(pcell);
}
for (auto &ncell : new_cells) {
ctx->cells[ncell->name] = std::move(ncell);
}
}
// Merge a net into a constant net
static 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) || is_lc(ctx, uc) || is_carry(ctx, uc)) && (user.port.str(ctx).at(0) == 'I') &&
!constval) {
uc->ports[user.port].net = nullptr;
} else if ((is_sb_mac16(ctx, uc) || uc->type == ctx->id("ICESTORM_DSP")) &&
(user.port != ctx->id("CLK") &&
((constval && user.port == ctx->id("CE")) || (!constval && user.port != ctx->id("CE"))))) {
uc->ports[user.port].net = nullptr;
} else if (is_ram(ctx, uc) && !constval && user.port != ctx->id("RCLK") && user.port != ctx->id("RCLKN") &&
user.port != ctx->id("WCLK") && user.port != ctx->id("WCLKN") && user.port != ctx->id("RCLKE") &&
user.port != ctx->id("WCLKE")) {
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)
static void pack_constants(Context *ctx)
{
log_info("Packing constants..\n");
std::unique_ptr<CellInfo> gnd_cell = create_ice_cell(ctx, ctx->id("ICESTORM_LC"), "$PACKER_GND");
gnd_cell->params[ctx->id("LUT_INIT")] = "0";
std::unique_ptr<NetInfo> gnd_net = std::unique_ptr<NetInfo>(new NetInfo);
gnd_net->name = ctx->id("$PACKER_GND_NET");
gnd_net->driver.cell = gnd_cell.get();
gnd_net->driver.port = ctx->id("O");
gnd_cell->ports.at(ctx->id("O")).net = gnd_net.get();
std::unique_ptr<CellInfo> vcc_cell = create_ice_cell(ctx, ctx->id("ICESTORM_LC"), "$PACKER_VCC");
vcc_cell->params[ctx->id("LUT_INIT")] = "1";
std::unique_ptr<NetInfo> vcc_net = std::unique_ptr<NetInfo>(new NetInfo);
vcc_net->name = ctx->id("$PACKER_VCC_NET");
vcc_net->driver.cell = vcc_cell.get();
vcc_net->driver.port = ctx->id("O");
vcc_cell->ports.at(ctx->id("O")).net = vcc_net.get();
std::vector<IdString> dead_nets;
bool gnd_used = false;
for (auto net : sorted(ctx->nets)) {
NetInfo *ni = net.second;
if (ni->driver.cell != nullptr && ni->driver.cell->type == ctx->id("GND")) {
IdString drv_cell = ni->driver.cell->name;
set_net_constant(ctx, ni, gnd_net.get(), false);
gnd_used = true;
dead_nets.push_back(net.first);
ctx->cells.erase(drv_cell);
} else if (ni->driver.cell != nullptr && ni->driver.cell->type == ctx->id("VCC")) {
IdString drv_cell = ni->driver.cell->name;
set_net_constant(ctx, ni, vcc_net.get(), true);
dead_nets.push_back(net.first);
ctx->cells.erase(drv_cell);
}
}
if (gnd_used) {
ctx->cells[gnd_cell->name] = std::move(gnd_cell);
ctx->nets[gnd_net->name] = std::move(gnd_net);
}
// Vcc cell always inserted for now, as it may be needed during carry legalisation (TODO: trim later if actually
// never used?)
ctx->cells[vcc_cell->name] = std::move(vcc_cell);
ctx->nets[vcc_net->name] = std::move(vcc_net);
for (auto dn : dead_nets) {
ctx->nets.erase(dn);
}
}
static bool is_nextpnr_iob(Context *ctx, CellInfo *cell)
{
return cell->type == ctx->id("$nextpnr_ibuf") || cell->type == ctx->id("$nextpnr_obuf") ||
cell->type == ctx->id("$nextpnr_iobuf");
}
// Pack IO buffers
static void pack_io(Context *ctx)
{
std::unordered_set<IdString> packed_cells;
std::unordered_set<IdString> delete_nets;
std::vector<std::unique_ptr<CellInfo>> new_cells;
log_info("Packing IOs..\n");
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_nextpnr_iob(ctx, ci)) {
CellInfo *sb = nullptr;
if (ci->type == ctx->id("$nextpnr_ibuf") || ci->type == ctx->id("$nextpnr_iobuf")) {
sb = net_only_drives(ctx, ci->ports.at(ctx->id("O")).net, is_sb_io, ctx->id("PACKAGE_PIN"), true, ci);
} else if (ci->type == ctx->id("$nextpnr_obuf")) {
sb = net_only_drives(ctx, ci->ports.at(ctx->id("I")).net, is_sb_io, ctx->id("PACKAGE_PIN"), true, ci);
}
if (sb != nullptr) {
// Trivial case, SB_IO used. Just destroy the net and the
// iobuf
log_info("%s feeds SB_IO %s, removing %s %s.\n", ci->name.c_str(ctx), sb->name.c_str(ctx),
ci->type.c_str(ctx), ci->name.c_str(ctx));
NetInfo *net = sb->ports.at(ctx->id("PACKAGE_PIN")).net;
if (((ci->type == ctx->id("$nextpnr_ibuf") || ci->type == ctx->id("$nextpnr_iobuf")) &&
net->users.size() > 1) ||
(ci->type == ctx->id("$nextpnr_obuf") && (net->users.size() > 2 || net->driver.cell != nullptr)))
log_error("PACKAGE_PIN of SB_IO '%s' connected to more than a single top level IO.\n",
sb->name.c_str(ctx));
if (net != nullptr) {
delete_nets.insert(net->name);
sb->ports.at(ctx->id("PACKAGE_PIN")).net = nullptr;
}
if (ci->type == ctx->id("$nextpnr_iobuf")) {
NetInfo *net2 = ci->ports.at(ctx->id("I")).net;
if (net2 != nullptr) {
delete_nets.insert(net2->name);
}
}
} else {
// Create a SB_IO buffer
std::unique_ptr<CellInfo> ice_cell =
create_ice_cell(ctx, ctx->id("SB_IO"), ci->name.str(ctx) + "$sb_io");
nxio_to_sb(ctx, ci, ice_cell.get(), packed_cells);
new_cells.push_back(std::move(ice_cell));
sb = new_cells.back().get();
}
packed_cells.insert(ci->name);
std::copy(ci->attrs.begin(), ci->attrs.end(), std::inserter(sb->attrs, sb->attrs.begin()));
} else if (is_sb_io(ctx, ci)) {
NetInfo *net = ci->ports.at(ctx->id("PACKAGE_PIN")).net;
if ((net != nullptr) && (net->users.size() > 1))
log_error("PACKAGE_PIN of SB_IO '%s' connected to more than a single top level IO.\n",
ci->name.c_str(ctx));
}
}
for (auto pcell : packed_cells) {
ctx->cells.erase(pcell);
}
for (auto dnet : delete_nets) {
ctx->nets.erase(dnet);
}
for (auto &ncell : new_cells) {
ctx->cells[ncell->name] = std::move(ncell);
}
}
// Return true if a port counts as "logic" for global promotion
static bool is_logic_port(BaseCtx *ctx, const PortRef &port)
{
if (is_clock_port(ctx, port) || is_reset_port(ctx, port) || is_enable_port(ctx, port))
return false;
return !is_sb_io(ctx, port.cell) && !is_sb_pll40(ctx, port.cell) && !is_sb_pll40_pad(ctx, port.cell) &&
port.cell->type != ctx->id("SB_GB");
}
static void insert_global(Context *ctx, NetInfo *net, bool is_reset, bool is_cen, bool is_logic)
{
log_info("promoting %s%s%s%s\n", net->name.c_str(ctx), is_reset ? " [reset]" : "", is_cen ? " [cen]" : "",
is_logic ? " [logic]" : "");
std::string glb_name = net->name.str(ctx) + std::string("_$glb_") + (is_reset ? "sr" : (is_cen ? "ce" : "clk"));
std::unique_ptr<CellInfo> gb = create_ice_cell(ctx, ctx->id("SB_GB"), "$gbuf_" + glb_name);
gb->ports[ctx->id("USER_SIGNAL_TO_GLOBAL_BUFFER")].net = net;
PortRef pr;
pr.cell = gb.get();
pr.port = ctx->id("USER_SIGNAL_TO_GLOBAL_BUFFER");
net->users.push_back(pr);
pr.cell = gb.get();
pr.port = ctx->id("GLOBAL_BUFFER_OUTPUT");
std::unique_ptr<NetInfo> glbnet = std::unique_ptr<NetInfo>(new NetInfo());
glbnet->name = ctx->id(glb_name);
glbnet->driver = pr;
gb->ports[ctx->id("GLOBAL_BUFFER_OUTPUT")].net = glbnet.get();
std::vector<PortRef> keep_users;
for (auto user : net->users) {
if (is_clock_port(ctx, user) || (is_reset && is_reset_port(ctx, user)) ||
(is_cen && is_enable_port(ctx, user)) || (is_logic && is_logic_port(ctx, user))) {
user.cell->ports[user.port].net = glbnet.get();
glbnet->users.push_back(user);
} else {
keep_users.push_back(user);
}
}
net->users = keep_users;
if (net->clkconstr) {
glbnet->clkconstr = std::unique_ptr<ClockConstraint>(new ClockConstraint());
glbnet->clkconstr->low = net->clkconstr->low;
glbnet->clkconstr->high = net->clkconstr->high;
glbnet->clkconstr->period = net->clkconstr->period;
}
ctx->nets[glbnet->name] = std::move(glbnet);
ctx->cells[gb->name] = std::move(gb);
}
// Simple global promoter (clock only)
static void promote_globals(Context *ctx)
{
log_info("Promoting globals..\n");
const int logic_fanout_thresh = 15;
const int enable_fanout_thresh = 5;
std::map<IdString, int> clock_count, reset_count, cen_count, logic_count;
for (auto net : sorted(ctx->nets)) {
NetInfo *ni = net.second;
if (ni->driver.cell != nullptr && !ctx->isGlobalNet(ni)) {
clock_count[net.first] = 0;
reset_count[net.first] = 0;
cen_count[net.first] = 0;
for (auto user : ni->users) {
if (is_clock_port(ctx, user))
clock_count[net.first]++;
if (is_reset_port(ctx, user))
reset_count[net.first]++;
if (is_enable_port(ctx, user))
cen_count[net.first]++;
if (is_logic_port(ctx, user))
logic_count[net.first]++;
}
}
}
int prom_globals = 0, prom_resets = 0, prom_cens = 0, prom_logics = 0;
int gbs_available = 8;
for (auto &cell : ctx->cells)
if (is_gbuf(ctx, cell.second.get()))
--gbs_available;
while (prom_globals < gbs_available) {
auto global_clock = std::max_element(clock_count.begin(), clock_count.end(),
[](const std::pair<IdString, int> &a, const std::pair<IdString, int> &b) {
return a.second < b.second;
});
auto global_reset = std::max_element(reset_count.begin(), reset_count.end(),
[](const std::pair<IdString, int> &a, const std::pair<IdString, int> &b) {
return a.second < b.second;
});
auto global_cen = std::max_element(cen_count.begin(), cen_count.end(),
[](const std::pair<IdString, int> &a, const std::pair<IdString, int> &b) {
return a.second < b.second;
});
auto global_logic = std::max_element(logic_count.begin(), logic_count.end(),
[](const std::pair<IdString, int> &a, const std::pair<IdString, int> &b) {
return a.second < b.second;
});
if (global_clock->second == 0 && prom_logics < 4 && global_logic->second > logic_fanout_thresh &&
(global_logic->second > global_cen->second || prom_cens >= 4) &&
(global_logic->second > global_reset->second || prom_resets >= 4)) {
NetInfo *logicnet = ctx->nets[global_logic->first].get();
insert_global(ctx, logicnet, false, false, true);
++prom_globals;
++prom_logics;
clock_count.erase(logicnet->name);
reset_count.erase(logicnet->name);
cen_count.erase(logicnet->name);
logic_count.erase(logicnet->name);
} else if (global_reset->second > global_clock->second && prom_resets < 4) {
NetInfo *rstnet = ctx->nets[global_reset->first].get();
insert_global(ctx, rstnet, true, false, false);
++prom_globals;
++prom_resets;
clock_count.erase(rstnet->name);
reset_count.erase(rstnet->name);
cen_count.erase(rstnet->name);
logic_count.erase(rstnet->name);
} else if (global_cen->second > global_clock->second && prom_cens < 4 &&
global_cen->second > enable_fanout_thresh) {
NetInfo *cennet = ctx->nets[global_cen->first].get();
insert_global(ctx, cennet, false, true, false);
++prom_globals;
++prom_cens;
clock_count.erase(cennet->name);
reset_count.erase(cennet->name);
cen_count.erase(cennet->name);
logic_count.erase(cennet->name);
} else if (global_clock->second != 0) {
NetInfo *clknet = ctx->nets[global_clock->first].get();
insert_global(ctx, clknet, false, false, false);
++prom_globals;
clock_count.erase(clknet->name);
reset_count.erase(clknet->name);
cen_count.erase(clknet->name);
logic_count.erase(clknet->name);
} else {
break;
}
}
}
// spliceLUT adds a pass-through LUT LC between the given cell's output port
// and either all users or only non_LUT users.
static std::unique_ptr<CellInfo> spliceLUT(Context *ctx, CellInfo *ci, IdString portId, bool onlyNonLUTs)
{
auto port = ci->ports[portId];
NPNR_ASSERT(port.net != nullptr);
// Create pass-through LUT.
std::unique_ptr<CellInfo> pt = create_ice_cell(ctx, ctx->id("ICESTORM_LC"),
ci->name.str(ctx) + "$nextpnr_" + portId.str(ctx) + "_lut_through");
pt->params[ctx->id("LUT_INIT")] = "65280"; // output is always I3
// Create LUT output net.
std::unique_ptr<NetInfo> out_net = std::unique_ptr<NetInfo>(new NetInfo);
out_net->name = ctx->id(ci->name.str(ctx) + "$nextnr_" + portId.str(ctx) + "_lut_through_net");
out_net->driver.cell = pt.get();
out_net->driver.port = ctx->id("O");
pt->ports.at(ctx->id("O")).net = out_net.get();
// New users of the original cell's port
std::vector<PortRef> new_users;
for (const auto &user : port.net->users) {
if (onlyNonLUTs && user.cell->type == ctx->id("ICESTORM_LC")) {
new_users.push_back(user);
continue;
}
// Rewrite pointer into net in user.
user.cell->ports[user.port].net = out_net.get();
// Add user to net.
PortRef pr;
pr.cell = user.cell;
pr.port = user.port;
out_net->users.push_back(pr);
}
// Add LUT to new users.
PortRef pr;
pr.cell = pt.get();
pr.port = ctx->id("I3");
new_users.push_back(pr);
pt->ports.at(ctx->id("I3")).net = port.net;
// Replace users of the original net.
port.net->users = new_users;
ctx->nets[out_net->name] = std::move(out_net);
return pt;
}
// Pack special functions
static void pack_special(Context *ctx)
{
log_info("Packing special functions..\n");
std::unordered_set<IdString> packed_cells;
std::vector<std::unique_ptr<CellInfo>> new_cells;
for (auto cell : sorted(ctx->cells)) {
CellInfo *ci = cell.second;
if (is_sb_lfosc(ctx, ci)) {
std::unique_ptr<CellInfo> packed =
create_ice_cell(ctx, ctx->id("ICESTORM_LFOSC"), ci->name.str(ctx) + "_OSC");
packed_cells.insert(ci->name);
replace_port(ci, ctx->id("CLKLFEN"), packed.get(), ctx->id("CLKLFEN"));
replace_port(ci, ctx->id("CLKLFPU"), packed.get(), ctx->id("CLKLFPU"));
if (/*bool_or_default(ci->attrs, ctx->id("ROUTE_THROUGH_FABRIC"))*/ true) { // FIXME
replace_port(ci, ctx->id("CLKLF"), packed.get(), ctx->id("CLKLF_FABRIC"));
} else {
replace_port(ci, ctx->id("CLKLF"), packed.get(), ctx->id("CLKLF"));
}
new_cells.push_back(std::move(packed));
} else if (is_sb_hfosc(ctx, ci)) {
std::unique_ptr<CellInfo> packed =
create_ice_cell(ctx, ctx->id("ICESTORM_HFOSC"), ci->name.str(ctx) + "_OSC");
packed_cells.insert(ci->name);
packed->params[ctx->id("CLKHF_DIV")] = str_or_default(ci->params, ctx->id("CLKHF_DIV"), "0b00");
replace_port(ci, ctx->id("CLKHFEN"), packed.get(), ctx->id("CLKHFEN"));
replace_port(ci, ctx->id("CLKHFPU"), packed.get(), ctx->id("CLKHFPU"));
if (/*bool_or_default(ci->attrs, ctx->id("ROUTE_THROUGH_FABRIC"))*/ true) { // FIXME
replace_port(ci, ctx->id("CLKHF"), packed.get(), ctx->id("CLKHF_FABRIC"));
} else {
replace_port(ci, ctx->id("CLKHF"), packed.get(), ctx->id("CLKHF"));
}
new_cells.push_back(std::move(packed));
} else if (is_sb_spram(ctx, ci)) {
std::unique_ptr<CellInfo> packed =
create_ice_cell(ctx, ctx->id("ICESTORM_SPRAM"), ci->name.str(ctx) + "_RAM");
packed_cells.insert(ci->name);
for (auto port : ci->ports) {
PortInfo &pi = port.second;
std::string newname = pi.name.str(ctx);
size_t bpos = newname.find('[');
if (bpos != std::string::npos) {
newname = newname.substr(0, bpos) + "_" + newname.substr(bpos + 1, (newname.size() - bpos) - 2);
}
replace_port(ci, ctx->id(pi.name.c_str(ctx)), packed.get(), ctx->id(newname));
}
new_cells.push_back(std::move(packed));
} else if (is_sb_mac16(ctx, ci)) {
std::unique_ptr<CellInfo> packed =
create_ice_cell(ctx, ctx->id("ICESTORM_DSP"), ci->name.str(ctx) + "_DSP");
packed_cells.insert(ci->name);
for (auto attr : ci->attrs)
packed->attrs[attr.first] = attr.second;
for (auto param : ci->params)
packed->params[param.first] = param.second;
for (auto port : ci->ports) {
PortInfo &pi = port.second;
std::string newname = pi.name.str(ctx);
size_t bpos = newname.find('[');
if (bpos != std::string::npos) {
newname = newname.substr(0, bpos) + "_" + newname.substr(bpos + 1, (newname.size() - bpos) - 2);
}
replace_port(ci, ctx->id(pi.name.c_str(ctx)), packed.get(), ctx->id(newname));
}
new_cells.push_back(std::move(packed));
} else if (is_sb_pll40(ctx, ci)) {
bool is_pad = is_sb_pll40_pad(ctx, ci);
bool is_core = !is_pad;
std::unique_ptr<CellInfo> packed =
create_ice_cell(ctx, ctx->id("ICESTORM_PLL"), ci->name.str(ctx) + "_PLL");
packed->attrs[ctx->id("TYPE")] = ci->type.str(ctx);
packed_cells.insert(ci->name);
for (auto attr : ci->attrs)
packed->attrs[attr.first] = attr.second;
for (auto param : ci->params)
packed->params[param.first] = param.second;
auto feedback_path = packed->params[ctx->id("FEEDBACK_PATH")];
packed->params[ctx->id("FEEDBACK_PATH")] =
feedback_path == "DELAY"
? "0"
: feedback_path == "SIMPLE" ? "1"
: feedback_path == "PHASE_AND_DELAY"
? "2"
: feedback_path == "EXTERNAL" ? "6" : feedback_path;
packed->params[ctx->id("PLLTYPE")] = std::to_string(sb_pll40_type(ctx, ci));
NetInfo *pad_packagepin_net = nullptr;
int pllout_a_used = 0;
int pllout_b_used = 0;
for (auto port : ci->ports) {
PortInfo &pi = port.second;
if (pi.name == ctx->id("PLLOUTCOREA"))
pllout_a_used++;
if (pi.name == ctx->id("PLLOUTCOREB"))
pllout_b_used++;
if (pi.name == ctx->id("PLLOUTCORE"))
pllout_a_used++;
if (pi.name == ctx->id("PLLOUTGLOBALA"))
pllout_a_used++;
if (pi.name == ctx->id("PLLOUTGLOBALB"))
pllout_b_used++;
if (pi.name == ctx->id("PLLOUTGLOBAL"))
pllout_a_used++;
}
if (pllout_a_used > 1)
log_error("PLL '%s' is using multiple ports mapping to PLLOUT_A output of the PLL\n",
ci->name.c_str(ctx));
if (pllout_b_used > 1)
log_error("PLL '%s' is using multiple ports mapping to PLLOUT_B output of the PLL\n",
ci->name.c_str(ctx));
for (auto port : ci->ports) {
PortInfo &pi = port.second;
std::string newname = pi.name.str(ctx);
size_t bpos = newname.find('[');
if (bpos != std::string::npos) {
newname = newname.substr(0, bpos) + "_" + newname.substr(bpos + 1, (newname.size() - bpos) - 2);
}
if (pi.name == ctx->id("PLLOUTCOREA"))
newname = "PLLOUT_A";
if (pi.name == ctx->id("PLLOUTCOREB"))
newname = "PLLOUT_B";
if (pi.name == ctx->id("PLLOUTCORE"))
newname = "PLLOUT_A";
if (pi.name == ctx->id("PLLOUTGLOBALA"))
newname = "PLLOUT_A";
if (pi.name == ctx->id("PLLOUTGLOBALB"))
newname = "PLLOUT_B";
if (pi.name == ctx->id("PLLOUTGLOBAL"))
newname = "PLLOUT_A";
if (pi.name == ctx->id("PLLOUTGLOBALA") || pi.name == ctx->id("PLLOUTGLOBALB") ||
pi.name == ctx->id("PLLOUTGLOBAL"))
log_warning("PLL '%s' is using port %s but implementation does not actually "
"use the global clock output of the PLL\n",
ci->name.c_str(ctx), pi.name.str(ctx).c_str());
if (pi.name == ctx->id("PACKAGEPIN")) {
if (!is_pad) {
log_error("PLL '%s' has a PACKAGEPIN but is not a PAD PLL\n", ci->name.c_str(ctx));
} else {
// We drop this port and instead place the PLL adequately below.
pad_packagepin_net = port.second.net;
NPNR_ASSERT(pad_packagepin_net != nullptr);
continue;
}
}
if (pi.name == ctx->id("REFERENCECLK")) {
if (!is_core)
log_error("PLL '%s' has a REFERENCECLK but is not a CORE PLL\n", ci->name.c_str(ctx));
}
if (packed->ports.count(ctx->id(newname)) == 0) {
if (ci->ports[pi.name].net == nullptr) {
log_warning("PLL '%s' has unknown unconnected port '%s' - ignoring\n", ci->name.c_str(ctx),
pi.name.c_str(ctx));
continue;
} else {
if (ctx->force) {
log_error("PLL '%s' has unknown connected port '%s'\n", ci->name.c_str(ctx),
pi.name.c_str(ctx));
} else {
log_warning("PLL '%s' has unknown connected port '%s' - ignoring\n", ci->name.c_str(ctx),
pi.name.c_str(ctx));
continue;
}
}
}
replace_port(ci, ctx->id(pi.name.c_str(ctx)), packed.get(), ctx->id(newname));
}
// If PLL is not constrained already, do that - we need this
// information to then constrain the LOCK LUT.
BelId pll_bel;
bool constrained = false;
if (packed->attrs.find(ctx->id("BEL")) == packed->attrs.end()) {
for (auto bel : ctx->getBels()) {
if (ctx->getBelType(bel) != id_ICESTORM_PLL)
continue;
// A PAD PLL must have its' PACKAGEPIN on the SB_IO that's shared
// with PLLOUT_A.
if (is_pad) {
auto pll_sb_io_belpin = ctx->getIOBSharingPLLPin(bel, id_PLLOUT_A);
NPNR_ASSERT(pad_packagepin_net != nullptr);
auto pll_packagepin_driver = pad_packagepin_net->driver;
NPNR_ASSERT(pll_packagepin_driver.cell != nullptr);
if (pll_packagepin_driver.cell->type != ctx->id("SB_IO")) {
log_error("PLL '%s' has a PACKAGEPIN driven by "
"an %s, should be directly connected to an input SB_IO\n",
ci->name.c_str(ctx), pll_packagepin_driver.cell->type.c_str(ctx));
}
auto packagepin_cell = pll_packagepin_driver.cell;
auto packagepin_bel_name = packagepin_cell->attrs.find(ctx->id("BEL"));
if (packagepin_bel_name == packagepin_cell->attrs.end()) {
log_error("PLL '%s' PACKAGEPIN SB_IO '%s' is unconstrained\n", ci->name.c_str(ctx),
packagepin_cell->name.c_str(ctx));
}
auto packagepin_bel = ctx->getBelByName(ctx->id(packagepin_bel_name->second));
if (pll_sb_io_belpin.bel != packagepin_bel) {
log_error("PLL '%s' PACKAGEPIN is connected to pin %s, can only be pin %s\n",
ci->name.c_str(ctx), ctx->getBelPackagePin(packagepin_bel).c_str(),
ctx->getBelPackagePin(pll_sb_io_belpin.bel).c_str());
}
if (pad_packagepin_net->users.size() != 1) {
log_error("PLL '%s' clock input '%s' can only drive PLL\n", ci->name.c_str(ctx),
pad_packagepin_net->name.c_str(ctx));
}
// Set an attribute about this PLL's PAD SB_IO.
packed->attrs[ctx->id("BEL_PAD_INPUT")] = packagepin_bel_name->second;
// Remove the connection from the SB_IO to the PLL.
packagepin_cell->ports.erase(pll_packagepin_driver.port);
}
log_info(" constrained PLL '%s' to %s\n", packed->name.c_str(ctx),
ctx->getBelName(bel).c_str(ctx));
packed->attrs[ctx->id("BEL")] = ctx->getBelName(bel).str(ctx);
pll_bel = bel;
constrained = true;
}
if (!constrained) {
log_error("Could not constrain PLL '%s' to any PLL Bel (too many PLLs?)\n",
packed->name.c_str(ctx));
}
}
// Delete the original PACKAGEPIN net if needed.
if (pad_packagepin_net != nullptr) {
for (auto user : pad_packagepin_net->users) {
user.cell->ports.erase(user.port);
}
ctx->nets.erase(pad_packagepin_net->name);
pad_packagepin_net = nullptr;
}
// The LOCK signal on iCE40 PLLs goes through the neigh_op_bnl_1 wire.
// In practice, this means the LOCK signal can only directly reach LUT
// inputs.
// If we have a net connected to LOCK, make sure it only drives LUTs.
auto port = packed->ports[ctx->id("LOCK")];
if (port.net != nullptr) {
log_info(" PLL '%s' has LOCK output, need to pass all outputs via LUT\n", ci->name.c_str(ctx));
bool found_lut = false;
bool all_luts = true;
unsigned int lut_count = 0;
for (const auto &user : port.net->users) {
NPNR_ASSERT(user.cell != nullptr);
if (user.cell->type == ctx->id("ICESTORM_LC")) {
found_lut = true;
lut_count++;
} else {
all_luts = false;
}
}
if (found_lut && all_luts) {
// Every user is a LUT, carry on now.
} else if (found_lut && !all_luts && lut_count < 8) {
// Strategy: create a pass-through LUT, move all non-LUT users behind it.
log_info(" LUT strategy for %s: move non-LUT users to new LUT\n", port.name.c_str(ctx));
auto pt = spliceLUT(ctx, packed.get(), port.name, true);
new_cells.push_back(std::move(pt));
} else {
// Strategy: create a pass-through LUT, move every user behind it.
log_info(" LUT strategy for %s: move all users to new LUT\n", port.name.c_str(ctx));
auto pt = spliceLUT(ctx, packed.get(), port.name, false);
new_cells.push_back(std::move(pt));
}
// Find wire that will be driven by this port.
const auto pll_out_wire = ctx->getBelPinWire(pll_bel, port.name);
NPNR_ASSERT(pll_out_wire.index != -1);
// Now, constrain all LUTs on the output of the signal to be at
// the correct Bel relative to the PLL Bel.
int x = ctx->chip_info->wire_data[pll_out_wire.index].x;
int y = ctx->chip_info->wire_data[pll_out_wire.index].y;
int z = 0;
for (const auto &user : port.net->users) {
NPNR_ASSERT(user.cell != nullptr);
NPNR_ASSERT(user.cell->type == ctx->id("ICESTORM_LC"));
// TODO(q3k): handle when the Bel might be already the
// target of another constraint.
NPNR_ASSERT(z < 8);
auto target_bel = ctx->getBelByLocation(Loc(x, y, z++));
auto target_bel_name = ctx->getBelName(target_bel).str(ctx);
user.cell->attrs[ctx->id("BEL")] = target_bel_name;
log_info(" constrained '%s' to %s\n", user.cell->name.c_str(ctx), target_bel_name.c_str());
}
}
new_cells.push_back(std::move(packed));
}
}
for (auto pcell : packed_cells) {
ctx->cells.erase(pcell);
}
for (auto &ncell : new_cells) {
ctx->cells[ncell->name] = std::move(ncell);
}
}
// Main pack function
bool Arch::pack()
{
Context *ctx = getCtx();
try {
log_break();
pack_constants(ctx);
promote_globals(ctx);
pack_io(ctx);
pack_lut_lutffs(ctx);
pack_nonlut_ffs(ctx);
pack_carries(ctx);
pack_ram(ctx);
pack_special(ctx);
ctx->assignArchInfo();
constrain_chains(ctx);
ctx->assignArchInfo();
log_info("Checksum: 0x%08x\n", ctx->checksum());
return true;
} catch (log_execution_error_exception) {
return false;
}
}
NEXTPNR_NAMESPACE_END
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