diff options
-rw-r--r-- | ecp5/globals.cc | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/ecp5/globals.cc b/ecp5/globals.cc index 9d51316c..453429e6 100644 --- a/ecp5/globals.cc +++ b/ecp5/globals.cc @@ -28,6 +28,21 @@ NEXTPNR_NAMESPACE_BEGIN +static std::string get_quad_name(GlobalQuadrant quad) +{ + switch (quad) { + case QUAD_UL: + return "UL"; + case QUAD_UR: + return "UR"; + case QUAD_LL: + return "LL"; + case QUAD_LR: + return "LR"; + } + return ""; +} + class Ecp5GlobalRouter { public: @@ -142,6 +157,79 @@ class Ecp5GlobalRouter } } + bool is_global_io(CellInfo *io, std::string &glb_name) + { + std::string func_name = ctx->getPioFunctionName(io->bel); + if (func_name.substr(0, 5) == "PCLKT") { + func_name.erase(func_name.find('_'), 1); + glb_name = "G_" + func_name; + return true; + } + return false; + } + + WireId get_global_wire(GlobalQuadrant quad, int network) + { + return ctx->getWireByLocAndBasename(Location(0, 0), get_quad_name(quad) + "PCLK" + std::to_string(network)); + } + + void simple_router(IdString net, WireId src, WireId dst) + { + std::queue<WireId> visit; + std::unordered_map<WireId, PipId> backtrace; + visit.push(src); + WireId cursor; + while (true) { + if (visit.empty() || visit.size() > 50000) { + log_error("cannot route global from %s to %s.\n", ctx->getWireName(src).c_str(ctx), + ctx->getWireName(dst).c_str(ctx)); + } + cursor = visit.back(); + visit.pop(); + IdString bound = ctx->getBoundWireNet(cursor); + if (bound == net) { + break; + } else if (bound != IdString()) { + continue; + } + if (cursor == dst) + break; + for (auto dh : ctx->getPipsDownhill(cursor)) { + WireId pipDst = ctx->getPipDstWire(dh); + if (backtrace.count(pipDst)) + continue; + backtrace[pipDst] = dh; + visit.push(pipDst); + } + } + while (true) { + auto fnd = backtrace.find(cursor); + if (fnd == backtrace.end()) + break; + ctx->bindPip(fnd->second, net, STRENGTH_LOCKED); + cursor = ctx->getPipSrcWire(fnd->second); + } + } + + void route_onto_global(NetInfo *net, int network) + { + WireId glb_src; + if (net->driver.cell->type == ctx->id("TRELLIS_IO")) { + std::string ioglb; + if (!is_global_io(net->driver.cell, ioglb)) + goto non_dedicated; + glb_src = ctx->getWireByLocAndBasename(Location(0, 0), ioglb); + } + for (int quad = QUAD_UL; quad < QUAD_LR + 1; quad++) { + WireId glb_dst = get_global_wire(GlobalQuadrant(quad), network); + simple_router(net->name, glb_src, glb_dst); + } + if (false) { + non_dedicated: + log_error("FIXME: currenly global networks can only be driven by dedicated global input pins"); + } + } + Context *ctx; }; |