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| author | R. Ou <rqou@robertou.com> | 2020-02-17 01:02:25 -0800 |
|---|---|---|
| committer | R. Ou <rqou@robertou.com> | 2020-02-17 03:08:52 -0800 |
| commit | 940bab68414f0a9dcd31fd3bf1ceb26b4c84b736 (patch) | |
| tree | a2158bd2e23249f19880373bafb1d656806af720 /passes/techmap/extract_counter.cc | |
| parent | 5fc180ed2d6da82892c7499392c0c5057c3aeec8 (diff) | |
| download | yosys-940bab68414f0a9dcd31fd3bf1ceb26b4c84b736.tar.gz yosys-940bab68414f0a9dcd31fd3bf1ceb26b4c84b736.tar.bz2 yosys-940bab68414f0a9dcd31fd3bf1ceb26b4c84b736.zip | |
extract_counter: Add support for inverted clock enable
Diffstat (limited to 'passes/techmap/extract_counter.cc')
| -rw-r--r-- | passes/techmap/extract_counter.cc | 36 |
1 files changed, 28 insertions, 8 deletions
diff --git a/passes/techmap/extract_counter.cc b/passes/techmap/extract_counter.cc index d1a0f6dec..8e280d19d 100644 --- a/passes/techmap/extract_counter.cc +++ b/passes/techmap/extract_counter.cc @@ -93,6 +93,7 @@ struct CounterExtraction RTLIL::Wire* rwire; //the register output bool has_reset; //true if we have a reset bool has_ce; //true if we have a clock enable + bool ce_inverted; //true if clock enable is active low RTLIL::SigSpec rst; //reset pin bool rst_inverted; //true if reset is active low bool rst_to_max; //true if we reset to max instead of 0 @@ -223,14 +224,24 @@ int counter_tryextract( return 24; count_reg = *cey_loads.begin(); - //Mux should have A driven by count Q, and B by muxy - //TODO: if A and B are swapped, CE polarity is inverted - if(sigmap(cemux->getPort(ID::B)) != muxy) - return 24; - if(sigmap(cemux->getPort(ID::A)) != sigmap(count_reg->getPort(ID(Q)))) - return 24; if(sigmap(cemux->getPort(ID::Y)) != sigmap(count_reg->getPort(ID(D)))) return 24; + //Mux should have A driven by count Q, and B by muxy + //if A and B are swapped, CE polarity is inverted + if(sigmap(cemux->getPort(ID::B)) == muxy && + sigmap(cemux->getPort(ID::A)) == sigmap(count_reg->getPort(ID(Q)))) + { + extract.ce_inverted = false; + } + else if(sigmap(cemux->getPort(ID::A)) == muxy && + sigmap(cemux->getPort(ID::B)) == sigmap(count_reg->getPort(ID(Q)))) + { + extract.ce_inverted = true; + } + else + { + return 24; + } //Select of the mux is our clock enable extract.has_ce = true; @@ -271,7 +282,9 @@ int counter_tryextract( //Sanity check that we use the ALU output properly if(extract.has_ce) { - if(!is_full_bus(muxy, index, count_mux, ID::Y, cemux, ID::B)) + if(!extract.ce_inverted && !is_full_bus(muxy, index, count_mux, ID::Y, cemux, ID::B)) + return 16; + if(extract.ce_inverted && !is_full_bus(muxy, index, count_mux, ID::Y, cemux, ID::A)) return 16; if(!is_full_bus(cey, index, cemux, ID::Y, count_reg, ID(D))) return 16; @@ -506,7 +519,14 @@ void counter_worker( if(extract.has_ce) { cell->setParam(ID(HAS_CE), RTLIL::Const(1)); - cell->setPort(ID(CE), extract.ce); + if(extract.ce_inverted) + { + auto realce = cell->module->addWire(NEW_ID); + cell->module->addNot(NEW_ID, extract.ce, RTLIL::SigSpec(realce)); + cell->setPort(ID(CE), realce); + } + else + cell->setPort(ID(CE), extract.ce); } else { |