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| author | David Shah <davey1576@gmail.com> | 2018-07-24 12:57:54 +0200 |
|---|---|---|
| committer | David Shah <davey1576@gmail.com> | 2018-07-24 12:57:54 +0200 |
| commit | 35a6bc496eb28f26c42e25a5e746987329e96f3e (patch) | |
| tree | 350f0a677556c1be5f1d37850732d875cd8d6dae /ecp5 | |
| parent | f61e9e56094946492bdd364ab272c19919a9faca (diff) | |
| download | nextpnr-35a6bc496eb28f26c42e25a5e746987329e96f3e.tar.gz nextpnr-35a6bc496eb28f26c42e25a5e746987329e96f3e.tar.bz2 nextpnr-35a6bc496eb28f26c42e25a5e746987329e96f3e.zip | |
ecp5: Support for differential IO
Signed-off-by: David Shah <davey1576@gmail.com>
Diffstat (limited to 'ecp5')
| -rw-r--r-- | ecp5/bitstream.cc | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/ecp5/bitstream.cc b/ecp5/bitstream.cc index 1efee5fc..c2218762 100644 --- a/ecp5/bitstream.cc +++ b/ecp5/bitstream.cc @@ -258,6 +258,20 @@ void write_bitstream(Context *ctx, std::string base_config_file, std::string tex std::string pic_tile = get_pic_tile(ctx, empty_chip, bel); cc.tiles[pio_tile].add_enum(pio + ".BASE_TYPE", dir + "_" + iotype); cc.tiles[pic_tile].add_enum(pio + ".BASE_TYPE", dir + "_" + iotype); + if (is_differential(ioType_from_str(iotype))) { + // Explicitly disable other pair + std::string other; + if (pio == "PIOA") + other = "PIOB"; + else if (pio == "PIOC") + other = "PIOD"; + else + log_error("cannot place differential IO at location %s\n", pio.c_str()); + cc.tiles[pio_tile].add_enum(other + ".BASE_TYPE", "_NONE_"); + cc.tiles[pic_tile].add_enum(other + ".BASE_TYPE", "_NONE_"); + cc.tiles[pio_tile].add_enum(other + ".PULLMODE", "NONE"); + cc.tiles[pio_tile].add_enum(pio + ".PULLMODE", "NONE"); + } if (dir != "INPUT" && (ci->ports.find(ctx->id("T")) == ci->ports.end() || ci->ports.at(ctx->id("T")).net == nullptr)) { // Tie tristate low if unconnected for outputs or bidir @@ -270,7 +284,7 @@ void write_bitstream(Context *ctx, std::string base_config_file, std::string tex std::string cib_wirename = ctx->locInfo(cib_wire)->wire_data[cib_wire.index].name.get(); cc.tiles[cib_tile].add_enum("CIB." + cib_wirename + "MUX", "0"); } - if (dir == "INPUT") { + if (dir == "INPUT" && !is_differential(ioType_from_str(iotype))) { cc.tiles[pio_tile].add_enum(pio + ".HYSTERESIS", "ON"); } } else { |