diff options
| -rw-r--r-- | gowin/constids.inc | 5 | ||||
| -rw-r--r-- | gowin/pack.cc | 82 |
2 files changed, 87 insertions, 0 deletions
diff --git a/gowin/constids.inc b/gowin/constids.inc index be016e0e..3e72340a 100644 --- a/gowin/constids.inc +++ b/gowin/constids.inc @@ -636,6 +636,8 @@ X(I) X(O) X(IO) X(OE) +X(OB) + // bels X(DFF0) X(DFF1) @@ -735,6 +737,7 @@ X(IBUF) X(OBUF) X(IOBUF) X(TBUF) +X(TLVDS_OBUF) // primitive attributes X(INIT) @@ -744,6 +747,8 @@ X(INPUT_USED) X(OUTPUT_USED) X(ENABLE_USED) X(BEL) +X(DIFF) +X(DIFF_TYPE) // ports X(EN) diff --git a/gowin/pack.cc b/gowin/pack.cc index 268f26ef..cc715864 100644 --- a/gowin/pack.cc +++ b/gowin/pack.cc @@ -678,6 +678,85 @@ static bool is_gowin_iob(const Context *ctx, const CellInfo *cell) } } +static bool is_gowin_diff_iob(const Context *ctx, const CellInfo *cell) +{ + switch (cell->type.index) { + case ID_TLVDS_OBUF: + return true; + default: + return false; + } +} + +static bool is_iob(const Context *ctx, const CellInfo *cell) { return (cell->type.index == ID_IOB); } + +// Pack differential IO buffers +static void pack_diff_io(Context *ctx) +{ + pool<IdString> packed_cells; + pool<IdString> delete_nets; + + std::vector<std::unique_ptr<CellInfo>> new_cells; + log_info("Packing diff IOs..\n"); + + for (auto &cell : ctx->cells) { + CellInfo *ci = cell.second.get(); + if (ctx->verbose) + log_info("cell '%s' is of type '%s'\n", ctx->nameOf(ci), ci->type.c_str(ctx)); + if (is_gowin_diff_iob(ctx, ci)) { + CellInfo *iob_p = nullptr; + CellInfo *iob_n = nullptr; + switch (ci->type.index) { + case ID_TLVDS_OBUF: { + iob_p = net_only_drives(ctx, ci->ports.at(id_O).net, is_iob, id_I); + iob_n = net_only_drives(ctx, ci->ports.at(id_OB).net, is_iob, id_I); + NPNR_ASSERT(iob_p != nullptr); + NPNR_ASSERT(iob_n != nullptr); + auto iob_p_bel_a = iob_p->attrs.find(id_BEL); + if (iob_p_bel_a == ci->attrs.end()) { + log_error("LVDS '%s' must be restricted.\n", ctx->nameOf(ci)); + continue; + } + BelId iob_p_bel = ctx->getBelByNameStr(iob_p_bel_a->second.as_string()); + Loc loc_p = ctx->getBelLocation(iob_p_bel); + if (loc_p.z != 0) { + log_error("LVDS '%s' positive pin is not A.\n", ctx->nameOf(ci)); + continue; + } + // restrict the N buffer + loc_p.z = 1; + iob_n->attrs[id_BEL] = ctx->getBelName(ctx->getBelByLocation(loc_p)).str(ctx); + // mark IOBs as part of DS pair + iob_n->attrs[id_DIFF] = std::string("N"); + iob_n->attrs[id_DIFF_TYPE] = std::string("TLVDS_OBUF"); + iob_p->attrs[id_DIFF] = std::string("P"); + iob_p->attrs[id_DIFF_TYPE] = std::string("TLVDS_OBUF"); + // disconnect N input: it is wired internally + delete_nets.insert(iob_n->ports.at(id_I).net->name); + iob_n->disconnectPort(id_I); + ci->disconnectPort(id_OB); + // disconnect P output + delete_nets.insert(ci->ports.at(id_O).net->name); + ci->disconnectPort(id_O); + // connect TLVDS input to P input + ci->movePortTo(id_I, iob_p, id_I); + packed_cells.insert(ci->name); + } break; + default: + break; + } + } + } + for (auto pcell : packed_cells) { + ctx->cells.erase(pcell); + } + for (auto dnet : delete_nets) { + ctx->nets.erase(dnet); + } + for (auto &ncell : new_cells) { + ctx->cells[ncell->name] = std::move(ncell); + } +} // Pack IO buffers static void pack_io(Context *ctx) { @@ -689,6 +768,8 @@ static void pack_io(Context *ctx) for (auto &cell : ctx->cells) { CellInfo *ci = cell.second.get(); + if (ctx->verbose) + log_info("cell '%s' is of type '%s'\n", ctx->nameOf(ci), ci->type.c_str(ctx)); if (is_gowin_iob(ctx, ci)) { CellInfo *iob = nullptr; switch (ci->type.index) { @@ -776,6 +857,7 @@ bool Arch::pack() log_break(); pack_constants(ctx); pack_io(ctx); + pack_diff_io(ctx); pack_wideluts(ctx); pack_alus(ctx); pack_lut_lutffs(ctx); |