ice40/pack: During IO packing, remove any unused input connection

This is mostly for the benefit of PLL placement because the D_IN_x
ports are used for other purposes when PLL is enabled so we need to
make sure nothing is connected there already. (even an unused net is
too much)

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
This commit is contained in:
Sylvain Munaut 2019-04-11 13:50:36 +02:00
parent 22da6c8a65
commit 6cb4e2e83b

View File

@ -502,6 +502,19 @@ static void pack_io(Context *ctx)
// Make it a normal SB_IO with global marker // Make it a normal SB_IO with global marker
ci->type = ctx->id("SB_IO"); ci->type = ctx->id("SB_IO");
ci->attrs[ctx->id("GLOBAL")] = "1"; ci->attrs[ctx->id("GLOBAL")] = "1";
} else if (is_sb_io(ctx, ci)) {
// Disconnect unused inputs
NetInfo *net_in0 = ci->ports.count(id_D_IN_0) ? ci->ports[id_D_IN_0].net : nullptr;
NetInfo *net_in1 = ci->ports.count(id_D_IN_1) ? ci->ports[id_D_IN_1].net : nullptr;
if (net_in0 != nullptr && net_in0->users.size() == 0) {
delete_nets.insert(net_in0->name);
ci->ports[id_D_IN_0].net = nullptr;
}
if (net_in1 != nullptr && net_in1->users.size() == 0) {
delete_nets.insert(net_in1->name);
ci->ports[id_D_IN_1].net = nullptr;
}
} }
} }
for (auto pcell : packed_cells) { for (auto pcell : packed_cells) {