From a6aeee4e1a41aa71d08ebac48686001ec050f973 Mon Sep 17 00:00:00 2001 From: "R. Ou" Date: Sun, 1 Mar 2020 06:54:07 -0800 Subject: coolrunner2: Insert many more required feedthrough cells --- techlibs/coolrunner2/coolrunner2_fixup.cc | 222 +++++++++++++++++++++++++----- 1 file changed, 186 insertions(+), 36 deletions(-) (limited to 'techlibs/coolrunner2/coolrunner2_fixup.cc') diff --git a/techlibs/coolrunner2/coolrunner2_fixup.cc b/techlibs/coolrunner2/coolrunner2_fixup.cc index bc1e8ff1b..c260fafdc 100644 --- a/techlibs/coolrunner2/coolrunner2_fixup.cc +++ b/techlibs/coolrunner2/coolrunner2_fixup.cc @@ -23,6 +23,58 @@ USING_YOSYS_NAMESPACE PRIVATE_NAMESPACE_BEGIN +RTLIL::Wire *makexorbuffer(RTLIL::Module *module, SigBit inwire) +{ + auto outwire = module->addWire(NEW_ID); + + if (inwire == SigBit(true)) + { + // Constant 1 + auto xor_cell = module->addCell(NEW_ID, "\\MACROCELL_XOR"); + xor_cell->setParam("\\INVERT_OUT", true); + xor_cell->setPort("\\OUT", outwire); + } + else if (inwire == SigBit(false)) + { + // Constant 0 + auto xor_cell = module->addCell(NEW_ID, "\\MACROCELL_XOR"); + xor_cell->setParam("\\INVERT_OUT", false); + xor_cell->setPort("\\OUT", outwire); + } + else + { + auto and_to_xor_wire = module->addWire(NEW_ID); + + auto and_cell = module->addCell(NEW_ID, "\\ANDTERM"); + and_cell->setParam("\\TRUE_INP", 1); + and_cell->setParam("\\COMP_INP", 0); + and_cell->setPort("\\OUT", and_to_xor_wire); + and_cell->setPort("\\IN", inwire); + and_cell->setPort("\\IN_B", SigSpec()); + + auto xor_cell = module->addCell(NEW_ID, "\\MACROCELL_XOR"); + xor_cell->setParam("\\INVERT_OUT", false); + xor_cell->setPort("\\IN_PTC", and_to_xor_wire); + xor_cell->setPort("\\OUT", outwire); + } + + return outwire; +} + +RTLIL::Wire *makeptermbuffer(RTLIL::Module *module, SigBit inwire) +{ + auto outwire = module->addWire(NEW_ID); + + auto and_cell = module->addCell(NEW_ID, "\\ANDTERM"); + and_cell->setParam("\\TRUE_INP", 1); + and_cell->setParam("\\COMP_INP", 0); + and_cell->setPort("\\OUT", outwire); + and_cell->setPort("\\IN", inwire); + and_cell->setPort("\\IN_B", SigSpec()); + + return outwire; +} + struct Coolrunner2FixupPass : public Pass { Coolrunner2FixupPass() : Pass("coolrunner2_fixup", "insert necessary buffer cells for CoolRunner-II architecture") { } void help() YS_OVERRIDE @@ -78,13 +130,58 @@ struct Coolrunner2FixupPass : public Pass { } } - // Start by buffering FF inputs. FF inputs can only come from either - // an IO pin or from an XOR. Otherwise AND/XOR cells need to be inserted. + // Find all the pterm outputs + pool sig_fed_by_pterm; + for (auto cell : module->selected_cells()) + { + if (cell->type == "\\ANDTERM") + { + auto output = sigmap(cell->getPort("\\OUT")[0]); + sig_fed_by_pterm.insert(output); + } + } + + // Find all the bufg outputs + pool sig_fed_by_bufg; + for (auto cell : module->selected_cells()) + { + if (cell->type == "\\BUFG") + { + auto output = sigmap(cell->getPort("\\O")[0]); + sig_fed_by_bufg.insert(output); + } + } + + // Find all the bufgsr outputs + pool sig_fed_by_bufgsr; + for (auto cell : module->selected_cells()) + { + if (cell->type == "\\BUFGSR") + { + auto output = sigmap(cell->getPort("\\O")[0]); + sig_fed_by_bufgsr.insert(output); + } + } + + // Find all the bufgts outputs + pool sig_fed_by_bufgts; + for (auto cell : module->selected_cells()) + { + if (cell->type == "\\BUFGTS") + { + auto output = sigmap(cell->getPort("\\O")[0]); + sig_fed_by_bufgts.insert(output); + } + } + for (auto cell : module->selected_cells()) { if (cell->type.in("\\FDCP", "\\FDCP_N", "\\FDDCP", "\\LDCP", "\\LDCP_N", "\\FTCP", "\\FTCP_N", "\\FTDCP", "\\FDCPE", "\\FDCPE_N", "\\FDDCPE")) { + // Buffering FF inputs. FF inputs can only come from either + // an IO pin or from an XOR. Otherwise AND/XOR cells need + // to be inserted. SigBit input; if (cell->type.in("\\FTCP", "\\FTCP_N", "\\FTDCP")) input = sigmap(cell->getPort("\\T")[0]); @@ -95,62 +192,115 @@ struct Coolrunner2FixupPass : public Pass { { log("Buffering input to \"%s\"\n", cell->name.c_str()); - auto and_to_xor_wire = module->addWire(NEW_ID); - auto xor_to_ff_wire = module->addWire(NEW_ID); - - auto and_cell = module->addCell(NEW_ID, "\\ANDTERM"); - and_cell->setParam("\\TRUE_INP", 1); - and_cell->setParam("\\COMP_INP", 0); - and_cell->setPort("\\OUT", and_to_xor_wire); - and_cell->setPort("\\IN", input); - and_cell->setPort("\\IN_B", SigSpec()); - - auto xor_cell = module->addCell(NEW_ID, "\\MACROCELL_XOR"); - xor_cell->setParam("\\INVERT_OUT", false); - xor_cell->setPort("\\IN_PTC", and_to_xor_wire); - xor_cell->setPort("\\OUT", xor_to_ff_wire); + auto xor_to_ff_wire = makexorbuffer(module, input); if (cell->type.in("\\FTCP", "\\FTCP_N", "\\FTDCP")) cell->setPort("\\T", xor_to_ff_wire); else cell->setPort("\\D", xor_to_ff_wire); } + + // Buffering FF clocks. FF clocks can only come from either + // a pterm or a bufg. In some cases this will be handled + // in coolrunner2_sop (e.g. if clock is generated from + // AND-ing two signals) but not in all cases. + SigBit clock; + if (cell->type.in("\\LDCP", "\\LDCP_N")) + clock = sigmap(cell->getPort("\\G")[0]); + else + clock = sigmap(cell->getPort("\\C")[0]); + + if (!sig_fed_by_pterm[clock] && !sig_fed_by_bufg[clock]) + { + log("Buffering clock to \"%s\"\n", cell->name.c_str()); + + auto pterm_to_ff_wire = makeptermbuffer(module, clock); + + if (cell->type.in("\\LDCP", "\\LDCP_N")) + cell->setPort("\\G", pterm_to_ff_wire); + else + cell->setPort("\\C", pterm_to_ff_wire); + } + + // Buffering FF set/reset. This can only come from either + // a pterm or a bufgsr. + SigBit set; + set = sigmap(cell->getPort("\\PRE")[0]); + if (set != SigBit(false)) + { + if (!sig_fed_by_pterm[set] && !sig_fed_by_bufgsr[set]) + { + log("Buffering set to \"%s\"\n", cell->name.c_str()); + + auto pterm_to_ff_wire = makeptermbuffer(module, set); + + cell->setPort("\\PRE", pterm_to_ff_wire); + } + } + + SigBit reset; + reset = sigmap(cell->getPort("\\CLR")[0]); + if (reset != SigBit(false)) + { + if (!sig_fed_by_pterm[reset] && !sig_fed_by_bufgsr[reset]) + { + log("Buffering reset to \"%s\"\n", cell->name.c_str()); + + auto pterm_to_ff_wire = makeptermbuffer(module, reset); + + cell->setPort("\\CLR", pterm_to_ff_wire); + } + } + + // Buffering FF clock enable + // FIXME: This doesn't fully fix PTC conflicts + // FIXME: Need to ensure constant enables are optimized out + if (cell->type.in("\\FDCPE", "\\FDCPE_N", "\\FDDCPE")) + { + SigBit ce; + ce = sigmap(cell->getPort("\\CE")[0]); + if (!sig_fed_by_pterm[ce]) + { + log("Buffering clock enable to \"%s\"\n", cell->name.c_str()); + + auto pterm_to_ff_wire = makeptermbuffer(module, ce); + + cell->setPort("\\CE", pterm_to_ff_wire); + } + } } } - // Buffer IOBUFE inputs. This can only be fed from an XOR or FF. for (auto cell : module->selected_cells()) { if (cell->type == "\\IOBUFE") { + // Buffer IOBUFE inputs. This can only be fed from an XOR or FF. SigBit input = sigmap(cell->getPort("\\I")[0]); - // Special case: constant 0 and 1 are handled by xc2par - if (input == SigBit(true) || input == SigBit(false)) { - log("Not buffering constant IO to \"%s\"\n", cell->name.c_str()); - continue; - } - if (!sig_fed_by_xor[input] && !sig_fed_by_ff[input]) { log("Buffering input to \"%s\"\n", cell->name.c_str()); - auto and_to_xor_wire = module->addWire(NEW_ID); - auto xor_to_io_wire = module->addWire(NEW_ID); + auto xor_to_io_wire = makexorbuffer(module, input); + + cell->setPort("\\I", xor_to_io_wire); + } - auto and_cell = module->addCell(NEW_ID, "\\ANDTERM"); - and_cell->setParam("\\TRUE_INP", 1); - and_cell->setParam("\\COMP_INP", 0); - and_cell->setPort("\\OUT", and_to_xor_wire); - and_cell->setPort("\\IN", input); - and_cell->setPort("\\IN_B", SigSpec()); + // Buffer IOBUFE enables. This can only be fed from a pterm + // or a bufgts. + if (cell->hasPort("\\E")) + { + SigBit oe; + oe = sigmap(cell->getPort("\\E")[0]); + if (!sig_fed_by_pterm[oe] && !sig_fed_by_bufgts[oe]) + { + log("Buffering output enable to \"%s\"\n", cell->name.c_str()); - auto xor_cell = module->addCell(NEW_ID, "\\MACROCELL_XOR"); - xor_cell->setParam("\\INVERT_OUT", false); - xor_cell->setPort("\\IN_PTC", and_to_xor_wire); - xor_cell->setPort("\\OUT", xor_to_io_wire); + auto pterm_to_oe_wire = makeptermbuffer(module, oe); - cell->setPort("\\I", xor_to_io_wire); + cell->setPort("\\E", pterm_to_oe_wire); + } } } } -- cgit v1.2.3