From a22f86f86192bbd782cc2fd430b2900ddb6740cc Mon Sep 17 00:00:00 2001 From: David Shah Date: Fri, 18 Oct 2019 16:32:55 +0100 Subject: ice40: Preserve top level IO properly Signed-off-by: David Shah --- ice40/cells.cc | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) (limited to 'ice40/cells.cc') diff --git a/ice40/cells.cc b/ice40/cells.cc index c4e93d5b..3f1a0fbf 100644 --- a/ice40/cells.cc +++ b/ice40/cells.cc @@ -426,7 +426,25 @@ void nxio_to_sb(Context *ctx, CellInfo *nxio, CellInfo *sbio, std::unordered_set } else { NPNR_ASSERT(false); } - NetInfo *donet = sbio->ports.at(ctx->id("D_OUT_0")).net; + NetInfo *donet = sbio->ports.at(ctx->id("D_OUT_0")).net, *dinet = sbio->ports.at(ctx->id("D_IN_0")).net; + + // Rename I/O nets to avoid conflicts + if (donet != nullptr && donet->name == nxio->name) + rename_net(ctx, donet, ctx->id(donet->name.str(ctx) + "$SB_IO_OUT")); + if (dinet != nullptr && dinet->name == nxio->name) + rename_net(ctx, dinet, ctx->id(dinet->name.str(ctx) + "$SB_IO_IN")); + + // Create a new top port net for accurate IO timing analysis and simulation netlists + if (ctx->ports.count(nxio->name)) { + IdString tn_netname = nxio->name; + NPNR_ASSERT(!ctx->nets.count(tn_netname)); + std::unique_ptr toplevel_net{new NetInfo}; + toplevel_net->name = tn_netname; + connect_port(ctx, toplevel_net.get(), sbio, ctx->id("PACKAGE_PIN")); + ctx->ports[nxio->name].net = toplevel_net.get(); + ctx->nets[tn_netname] = std::move(toplevel_net); + } + CellInfo *tbuf = net_driven_by( ctx, donet, [](const Context *ctx, const CellInfo *cell) { return cell->type == ctx->id("$_TBUF_"); }, ctx->id("Y")); -- cgit v1.2.3