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author | Clifford Wolf <clifford@clifford.at> | 2018-03-31 13:31:01 +0200 |
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committer | GitHub <noreply@github.com> | 2018-03-31 13:31:01 +0200 |
commit | 7ea8833676d8b388a57be2d0c1c7a6b1e450226a (patch) | |
tree | 14569db0d55a8adfb3b47853f88395613b3a8222 | |
parent | dd5fab69c135135fa46b6325a39c184a2ddc6156 (diff) | |
parent | 14e49fb05737cfb02217b2aaf14d9f5d9e1859da (diff) | |
download | yosys-7ea8833676d8b388a57be2d0c1c7a6b1e450226a.tar.gz yosys-7ea8833676d8b388a57be2d0c1c7a6b1e450226a.tar.bz2 yosys-7ea8833676d8b388a57be2d0c1c7a6b1e450226a.zip |
Merge pull request #521 from azonenberg/for_clifford
coolrunner2: Improve optimization for TFF/counters
-rw-r--r-- | techlibs/coolrunner2/Makefile.inc | 1 | ||||
-rw-r--r-- | techlibs/coolrunner2/coolrunner2_sop.cc | 58 | ||||
-rw-r--r-- | techlibs/coolrunner2/synth_coolrunner2.cc | 13 | ||||
-rw-r--r-- | techlibs/coolrunner2/tff_extract.v | 41 |
4 files changed, 113 insertions, 0 deletions
diff --git a/techlibs/coolrunner2/Makefile.inc b/techlibs/coolrunner2/Makefile.inc index 96bbb0f47..d62c9960c 100644 --- a/techlibs/coolrunner2/Makefile.inc +++ b/techlibs/coolrunner2/Makefile.inc @@ -4,4 +4,5 @@ OBJS += techlibs/coolrunner2/coolrunner2_sop.o $(eval $(call add_share_file,share/coolrunner2,techlibs/coolrunner2/cells_latch.v)) $(eval $(call add_share_file,share/coolrunner2,techlibs/coolrunner2/cells_sim.v)) +$(eval $(call add_share_file,share/coolrunner2,techlibs/coolrunner2/tff_extract.v)) $(eval $(call add_share_file,share/coolrunner2,techlibs/coolrunner2/xc2_dff.lib)) diff --git a/techlibs/coolrunner2/coolrunner2_sop.cc b/techlibs/coolrunner2/coolrunner2_sop.cc index b57214ccb..431e0a127 100644 --- a/techlibs/coolrunner2/coolrunner2_sop.cc +++ b/techlibs/coolrunner2/coolrunner2_sop.cc @@ -250,6 +250,64 @@ struct Coolrunner2SopPass : public Pass { } } + // In some cases we can get a FF feeding straight into an FF. This is not possible, so we need to insert + // some AND/XOR cells in the middle to make it actually work. + + // Find all the FF outputs + pool<SigBit> sig_fed_by_ff; + for (auto cell : module->selected_cells()) + { + if (cell->type == "\\FDCP" || cell->type == "\\FDCP_N" || cell->type == "\\FDDCP" || + cell->type == "\\LDCP" || cell->type == "\\LDCP_N" || + cell->type == "\\FTCP" || cell->type == "\\FTCP_N" || cell->type == "\\FTDCP" || + cell->type == "\\FDCPE" || cell->type == "\\FDCPE_N" || cell->type == "\\FDDCPE") + { + auto output = sigmap(cell->getPort("\\Q")[0]); + sig_fed_by_ff.insert(output); + } + } + + // Look at all the FF inputs + for (auto cell : module->selected_cells()) + { + if (cell->type == "\\FDCP" || cell->type == "\\FDCP_N" || cell->type == "\\FDDCP" || + cell->type == "\\LDCP" || cell->type == "\\LDCP_N" || + cell->type == "\\FTCP" || cell->type == "\\FTCP_N" || cell->type == "\\FTDCP" || + cell->type == "\\FDCPE" || cell->type == "\\FDCPE_N" || cell->type == "\\FDDCPE") + { + SigBit input; + if (cell->type == "\\FTCP" || cell->type == "\\FTCP_N" || cell->type == "\\FTDCP") + input = sigmap(cell->getPort("\\T")[0]); + else + input = sigmap(cell->getPort("\\D")[0]); + + if (sig_fed_by_ff[input]) + { + printf("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); + + if (cell->type == "\\FTCP" || cell->type == "\\FTCP_N" || cell->type == "\\FTDCP") + cell->setPort("\\T", xor_to_ff_wire); + else + cell->setPort("\\D", xor_to_ff_wire); + } + } + } + // Actually do the removal now that we aren't iterating for (auto cell : cells_to_remove) { diff --git a/techlibs/coolrunner2/synth_coolrunner2.cc b/techlibs/coolrunner2/synth_coolrunner2.cc index 183282629..2e94c3449 100644 --- a/techlibs/coolrunner2/synth_coolrunner2.cc +++ b/techlibs/coolrunner2/synth_coolrunner2.cc @@ -149,6 +149,16 @@ struct SynthCoolrunner2Pass : public ScriptPass run("dfflibmap -prepare -liberty +/coolrunner2/xc2_dff.lib"); } + if (check_label("map_tff")) + { + // This is quite hacky. By telling abc that it can only use AND and XOR gates, abc will try and use XOR + // gates "whenever possible." This will hopefully cause toggle flip-flop structures to turn into an XOR + // connected to a D flip-flop. We then match on these and convert them into XC2 TFF cells. + run("abc -g AND,XOR"); + run("clean"); + run("extract -map +/coolrunner2/tff_extract.v"); + } + if (check_label("map_pla")) { run("abc -sop -I 40 -P 56"); @@ -160,12 +170,15 @@ struct SynthCoolrunner2Pass : public ScriptPass run("dfflibmap -liberty +/coolrunner2/xc2_dff.lib"); run("dffinit -ff FDCP Q INIT"); run("dffinit -ff FDCP_N Q INIT"); + run("dffinit -ff FTCP Q INIT"); + run("dffinit -ff FTCP_N Q INIT"); run("dffinit -ff LDCP Q INIT"); run("dffinit -ff LDCP_N Q INIT"); run("coolrunner2_sop"); run("iopadmap -bits -inpad IBUF O:I -outpad IOBUFE I:IO -inoutpad IOBUFE O:IO -toutpad IOBUFE E:I:IO -tinoutpad IOBUFE E:O:I:IO"); run("attrmvcp -attr src -attr LOC t:IOBUFE n:*"); run("attrmvcp -attr src -attr LOC -driven t:IBUF n:*"); + run("splitnets"); run("clean"); } diff --git a/techlibs/coolrunner2/tff_extract.v b/techlibs/coolrunner2/tff_extract.v new file mode 100644 index 000000000..b4237dd18 --- /dev/null +++ b/techlibs/coolrunner2/tff_extract.v @@ -0,0 +1,41 @@ +module FTCP (C, PRE, CLR, T, Q); + input C, PRE, CLR, T; + output wire Q; + + wire xorout; + + $_XOR_ xorgate ( + .A(T), + .B(Q), + .Y(xorout), + ); + + $_DFFSR_PPP_ dff ( + .C(C), + .D(xorout), + .Q(Q), + .S(PRE), + .R(CLR), + ); +endmodule + +module FTCP_N (C, PRE, CLR, T, Q); + input C, PRE, CLR, T; + output wire Q; + + wire xorout; + + $_XOR_ xorgate ( + .A(T), + .B(Q), + .Y(xorout), + ); + + $_DFFSR_NPP_ dff ( + .C(C), + .D(xorout), + .Q(Q), + .S(PRE), + .R(CLR), + ); +endmodule |