From 66670831b89d934ef00c47c0527137f6ec38a0b0 Mon Sep 17 00:00:00 2001 From: David Shah Date: Thu, 28 Jun 2018 16:31:52 +0200 Subject: ice40: PLace legaliser produces a design that is at least routable for picosoc Signed-off-by: David Shah --- ice40/place_legaliser.cc | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'ice40/place_legaliser.cc') diff --git a/ice40/place_legaliser.cc b/ice40/place_legaliser.cc index 1292d094..91350c2b 100644 --- a/ice40/place_legaliser.cc +++ b/ice40/place_legaliser.cc @@ -155,6 +155,22 @@ class PlacementLegaliser return i3_next;*/ return (CellInfo *)nullptr; }); + std::unordered_set chained; + for (auto &base_chain : carry_chains) { + for (auto c : base_chain.cells) + chained.insert(c->name); + } + // Any cells not in chains, but with carry enabled, must also be put in a single-carry chain + // for correct processing + for (auto cell : sorted(ctx->cells)) { + CellInfo *ci = cell.second; + if (chained.find(cell.first) == chained.end() && is_lc(ctx, ci) && bool_or_default(ci->params, ctx->id("CARRY_ENABLE"))) { + CellChain sChain; + sChain.cells.push_back(ci); + chained.insert(cell.first); + carry_chains.push_back(sChain); + } + } bool success = true; // Find midpoints for all chains, before we start tearing them up std::vector all_chains; @@ -274,6 +290,7 @@ class PlacementLegaliser CellInfo *passout = make_carry_pass_out(cell->ports.at(ctx->id("COUT"))); chains.back().cells.push_back(passout); tile.push_back(passout); + start_of_chain = true; } } ++curr_cell; -- cgit v1.2.3