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-rw-r--r--ecp5/pack.cc131
1 files changed, 120 insertions, 11 deletions
diff --git a/ecp5/pack.cc b/ecp5/pack.cc
index c0427d46..11cc2647 100644
--- a/ecp5/pack.cc
+++ b/ecp5/pack.cc
@@ -71,6 +71,15 @@ class Ecp5Packer
}
}
+ 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)
{
@@ -88,11 +97,11 @@ class Ecp5Packer
if (str_or_default(ff0->params, ctx->id("CLKMUX"), "CLK") !=
str_or_default(ff1->params, ctx->id("CLKMUX"), "CLK"))
return false;
- if (ff0->ports.at(ctx->id("CLK")).net != ff1->ports.at(ctx->id("CLK")).net)
+ if (net_or_nullptr(ff0, ctx->id("CLK")) != net_or_nullptr(ff1, ctx->id("CLK")))
return false;
- if (ff0->ports.at(ctx->id("CE")).net != ff1->ports.at(ctx->id("CE")).net)
+ if (net_or_nullptr(ff0, ctx->id("CE")) != net_or_nullptr(ff1, ctx->id("CE")))
return false;
- if (ff0->ports.at(ctx->id("LSR")).net != ff1->ports.at(ctx->id("LSR")).net)
+ if (net_or_nullptr(ff0, ctx->id("LSR")) != net_or_nullptr(ff1, ctx->id("LSR")))
return false;
return true;
}
@@ -223,8 +232,23 @@ class Ecp5Packer
} 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();
@@ -275,6 +299,8 @@ class Ecp5Packer
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));
@@ -304,10 +330,14 @@ class Ecp5Packer
if (ff0 != lutffPairs.end()) {
ff_to_slice(ctx, ctx->cells.at(ff0->second).get(), slice.get(), 0, true);
packed_cells.insert(ff0->second);
+ lutffPairs.erase(lut0->name);
+ fflutPairs.erase(ff0->second);
}
if (ff1 != lutffPairs.end()) {
ff_to_slice(ctx, ctx->cells.at(ff1->second).get(), slice.get(), 1, true);
packed_cells.insert(ff1->second);
+ lutffPairs.erase(lut1->name);
+ fflutPairs.erase(ff1->second);
}
new_cells.push_back(std::move(slice));
@@ -333,6 +363,8 @@ class Ecp5Packer
if (ff != lutffPairs.end()) {
ff_to_slice(ctx, ctx->cells.at(ff->second).get(), slice.get(), 0, true);
packed_cells.insert(ff->second);
+ lutffPairs.erase(ci->name);
+ fflutPairs.erase(ff->second);
}
new_cells.push_back(std::move(slice));
@@ -374,21 +406,98 @@ class Ecp5Packer
new_init |= (1 << i);
}
}
- cell->params[ctx->id("INIT")] = std::to_string(init);
- NetInfo *innet = cell->ports.at(input).net;
- if (innet != nullptr) {
- innet->users.erase(
- std::remove_if(innet->users.begin(), innet->users.end(),
- [cell, input](PortRef port) { return port.cell == cell && port.port == input; }),
- innet->users.end());
- }
+ 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();
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-10 09:04:20 +0000