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| author | gatecat <gatecat@ds0.me> | 2021-05-13 23:46:08 +0100 |
|---|---|---|
| committer | gatecat <gatecat@ds0.me> | 2021-05-15 14:54:33 +0100 |
| commit | e688ee0e89263bc39a0ea10ac552430e41824aa1 (patch) | |
| tree | 972186d1e80c09472851b49918d00a0228954a37 /mistral | |
| parent | 3313d5267a4e4609d694d15e66040b0829788bb4 (diff) | |
| download | nextpnr-e688ee0e89263bc39a0ea10ac552430e41824aa1.tar.gz nextpnr-e688ee0e89263bc39a0ea10ac552430e41824aa1.tar.bz2 nextpnr-e688ee0e89263bc39a0ea10ac552430e41824aa1.zip | |
mistral: Debugging carry chain issues
Signed-off-by: gatecat <gatecat@ds0.me>
Diffstat (limited to 'mistral')
| -rw-r--r-- | mistral/lab.cc | 29 | ||||
| -rw-r--r-- | mistral/pack.cc | 18 |
2 files changed, 34 insertions, 13 deletions
diff --git a/mistral/lab.cc b/mistral/lab.cc index 7d798cbc..2d57ed42 100644 --- a/mistral/lab.cc +++ b/mistral/lab.cc @@ -42,20 +42,20 @@ static void create_alm(Arch *arch, int x, int y, int z, uint32_t lab_idx) WireId carry_in, share_in; WireId carry_out, share_out; if (z == 0 && i == 0) { - if (y == arch->getGridDimY() - 1) { - // Base case - carry_in = arch->add_wire(x, y, id_CARRY_START); - share_in = arch->add_wire(x, y, id_CARRY_START); - } else { - // Output of last tile - carry_in = arch->add_wire(x, y + 1, id_CO); - share_in = arch->add_wire(x, y + 1, id_SHAREOUT); + carry_in = arch->add_wire(x, y, id_CI); + share_in = arch->add_wire(x, y, id_SHAREIN); + if (y < (arch->getGridDimY() - 1)) { + // Carry is split at tile boundary (TTO_DIS bit), add a PIP to represent this. + // TODO: what about BTO_DIS, in the middle of the LAB? + arch->add_pip(arch->add_wire(x, y + 1, id_CO), carry_in); + arch->add_pip(arch->add_wire(x, y + 1, id_SHAREOUT), share_in); } } else { // Output from last combinational unit carry_in = arch->add_wire(x, y, arch->id(stringf("CARRY[%d]", (z * 2 + i) - 1))); share_in = arch->add_wire(x, y, arch->id(stringf("SHARE[%d]", (z * 2 + i) - 1))); } + if (z == 9 && i == 1) { carry_out = arch->add_wire(x, y, id_CO); share_out = arch->add_wire(x, y, id_SHAREOUT); @@ -582,7 +582,7 @@ static void assign_lut6_inputs(CellInfo *cell, int lut) if (!cell->ports.count(log) || cell->ports.at(log).net == nullptr) continue; cell->pin_data[log].bel_pins.clear(); - cell->pin_data[log].bel_pins.push_back(phys_pins.at(++phys_idx)); + cell->pin_data[log].bel_pins.push_back(phys_pins.at(phys_idx++)); } } } // namespace @@ -640,16 +640,19 @@ void Arch::reassign_alm_inputs(uint32_t lab, uint8_t alm) continue; // Work out which physical ports are available std::vector<IdString> avail_phys_ports; + // D/C always available and dedicated to the half, in L5 mode avail_phys_ports.push_back((i == 1) ? id_D : id_C); - if (b_avail) - avail_phys_ports.push_back(id_B); - if (a_avail) - avail_phys_ports.push_back(id_A); // In arithmetic mode, Ei can only be used for D0 and Fi can only be used for D1 + // otherwise, these are general and dedicated to one half if (!luts[i]->combInfo.is_carry) { avail_phys_ports.push_back((i == 1) ? id_E1 : id_E0); avail_phys_ports.push_back((i == 1) ? id_F1 : id_F0); } + // A and B might be used for shared signals, or already used by the other half + if (b_avail) + avail_phys_ports.push_back(id_B); + if (a_avail) + avail_phys_ports.push_back(id_A); int phys_idx = 0; for (int j = 0; j < luts[i]->combInfo.lut_input_count; j++) { diff --git a/mistral/pack.cc b/mistral/pack.cc index b86393d7..f8c55cd1 100644 --- a/mistral/pack.cc +++ b/mistral/pack.cc @@ -312,6 +312,24 @@ struct MistralPacker chain.at(i)->cluster = chain.at(0)->name; chain.at(0)->constr_children.push_back(chain.at(i)); } + + if (ctx->debug) { + log_info("Chain: \n"); + for (int i = 0; i < int(chain.size()); i++) { + auto &c = chain.at(i); + log_info(" i=%d cell=%s dy=%d z=%d ci=%s co=%s\n", i, ctx->nameOf(c), c->constr_y, c->constr_z, + ctx->nameOf(get_net_or_empty(c, id_CI)), ctx->nameOf(get_net_or_empty(c, id_CO))); + } + } + } + // Check we reached all the cells in the above pass + for (auto cell : sorted(ctx->cells)) { + CellInfo *ci = cell.second; + if (ci->type != id_MISTRAL_ALUT_ARITH) + continue; + if (ci->cluster == ClusterId()) + log_error("Failed to include arith cell '%s' in any chain (CI=%s)\n", ctx->nameOf(ci), + ctx->nameOf(get_net_or_empty(ci, id_CI))); } } |