diff options
Diffstat (limited to 'generic/viaduct/fabulous/fasm.cc')
| -rw-r--r-- | generic/viaduct/fabulous/fasm.cc | 42 |
1 files changed, 41 insertions, 1 deletions
diff --git a/generic/viaduct/fabulous/fasm.cc b/generic/viaduct/fabulous/fasm.cc index 4d09d537..159bb8ff 100644 --- a/generic/viaduct/fabulous/fasm.cc +++ b/generic/viaduct/fabulous/fasm.cc @@ -122,11 +122,51 @@ struct FabFasmWriter void add_feature(const std::string &name) { out << prefix << name << std::endl; } + uint64_t depermute_lut(const CellInfo *lut) + { + uint64_t orig_init = int_or_default(lut->params, id_INIT, 0); + std::vector<std::vector<unsigned>> phys_to_log; + phys_to_log.resize(cfg.clb.lut_k); + for (unsigned i = 0; i < cfg.clb.lut_k; i++) { + WireId pin_wire = ctx->getBelPinWire(lut->bel, ctx->idf("I%d", i)); + for (PipId pip : ctx->getPipsUphill(pin_wire)) { + if (!ctx->getBoundPipNet(pip)) + continue; + unsigned pip_data = pip_tags.at(pip.index).data; + unsigned from_pin = (pip_data >> 4) & 0xF; + unsigned to_pin = (pip_data)&0xF; + NPNR_ASSERT(to_pin == i); + phys_to_log[from_pin].push_back(i); + } + } + if (bool_or_default(lut->params, id_I0MUX, false)) // internal, hardcoded + phys_to_log[0].push_back(0); + for (unsigned i = 0; i < cfg.clb.lut_k; i++) { + for (auto j : phys_to_log.at(i)) + out << stringf(" # permute phys %d log %d\n", i, j); + } + uint64_t permuted_init = 0; + for (unsigned i = 0; i < (1U << cfg.clb.lut_k); i++) { + unsigned log_idx = 0; + for (unsigned j = 0; j < cfg.clb.lut_k; j++) { + if ((i >> j) & 0x1) { + for (auto log_pin : phys_to_log[j]) + log_idx |= (1 << log_pin); + } + } + if ((orig_init >> log_idx) & 0x1) + permuted_init |= (uint64_t(1U) << i); + } + return permuted_init; + } + void write_logic(const CellInfo *lc) { prefix = format_name(ctx->getBelName(lc->bel)) + "."; if (lc->type.in(id_FABULOUS_LC, id_FABULOUS_COMB)) { - write_int_vector_param(lc, "INIT", 0U, 1U << cfg.clb.lut_k); // todo lut depermute and thru + uint64_t init = depermute_lut(lc); + unsigned width = 1U << cfg.clb.lut_k; + write_int_vector(stringf("INIT[%d:0]", width - 1), init, width); // todo lut depermute and thru if (bool_or_default(lc->params, id_I0MUX, false)) add_feature("IOmux"); // typo in FABulous? } |