machxo2: Detect LOC attributes during packing to implement rudimentary user constraints.

This commit is contained in:
William D. Jones 2020-12-08 01:42:58 -05:00 committed by gatecat
parent 8417470276
commit 9c37aef499
3 changed files with 61 additions and 0 deletions

View File

@ -262,6 +262,21 @@ std::vector<IdString> Arch::getBelPins(BelId bel) const
// ---------------------------------------------------------------
BelId Arch::getPackagePinBel(const std::string &pin) const
{
for (int i = 0; i < package_info->num_pins; i++) {
if (package_info->pin_data[i].name.get() == pin) {
BelId bel;
bel.location = package_info->pin_data[i].abs_loc;
bel.index = package_info->pin_data[i].bel_index;
return bel;
}
}
return BelId();
}
// ---------------------------------------------------------------
WireId Arch::getWireByName(IdString name) const { return WireId(); }
IdString Arch::getWireName(WireId wire) const { return IdString(); }

View File

@ -606,6 +606,9 @@ struct Arch : BaseCtx
PortType getBelPinType(BelId bel, IdString pin) const;
std::vector<IdString> getBelPins(BelId bel) const;
// Package
BelId getPackagePinBel(const std::string &pin) const;
// Wires
WireId getWireByName(IdString name) const;
IdString getWireName(WireId wire) const;

View File

@ -175,6 +175,49 @@ static void pack_io(Context *ctx)
for (auto &p : ci->ports)
disconnect_port(ctx, ci, p.first);
packed_cells.insert(ci->name);
} else if(is_facade_iob(ctx, ci)) {
// If net attached to PAD port of FACADE_IO has a LOC attribute OR
// FACADE_IO has LOC attribute, convert the LOC (pin) to a BEL
// attribute and place FACADE_IO at resulting BEL location.
auto pad_net = ci->ports[id_PAD].net;
auto loc_attr_pad = pad_net->attrs.find(ctx->id("LOC"));
auto loc_attr_cell = ci->attrs.find(ctx->id("LOC"));
auto bel_attr_cell = ci->attrs.find(ctx->id("BEL"));
// Handle errors
if(loc_attr_pad != pad_net->attrs.end() && loc_attr_cell != ci->attrs.end())
log_error("IO buffer %s and attached PAD net %s both have LOC attributes.\n",
ci->name.c_str(ctx), pad_net->name.c_str(ctx));
else if(loc_attr_pad != pad_net->attrs.end() && bel_attr_cell != ci->attrs.end())
log_error("IO buffer %s has a BEL attribute and attached PAD net %s has a LOC attribute.\n",
ci->name.c_str(ctx), pad_net->name.c_str(ctx));
else if(loc_attr_cell != ci->attrs.end() && bel_attr_cell != ci->attrs.end())
log_error("IO buffer %s has both a BEL attribute and LOC attribute.\n",
ci->name.c_str(ctx));
std::string pin;
// At this point only PAD net or FACADE_IO has LOC attribute.
if(loc_attr_pad != pad_net->attrs.end()) {
pin = loc_attr_pad->second.as_string();
log_info("found LOC attribute on net %s. Will constrain IO buffer %s.\n",
pad_net->name.c_str(ctx), ci->name.c_str(ctx));
} else if(loc_attr_cell != ci->attrs.end()) {
log_info("found LOC attribute on IO buffer %s.\n", ci->name.c_str(ctx));
pin = loc_attr_cell->second.as_string();
} else
// Nothing to do if no LOC attrs.
continue;
BelId pinBel = ctx->getPackagePinBel(pin);
if (pinBel == BelId()) {
log_error("IO buffer '%s' constrained to pin '%s', which does not exist for package '%s'.\n",
ci->name.c_str(ctx), pin.c_str(), ctx->args.package.c_str());
} else {
log_info("pin '%s' constrained to Bel '%s'.\n", ci->name.c_str(ctx),
ctx->getBelName(pinBel).c_str(ctx));
}
ci->attrs[ctx->id("BEL")] = ctx->getBelName(pinBel).str(ctx);
}
}