diff options
Diffstat (limited to 'techlibs/xilinx/synth_xilinx.cc')
| -rw-r--r-- | techlibs/xilinx/synth_xilinx.cc | 122 |
1 files changed, 94 insertions, 28 deletions
diff --git a/techlibs/xilinx/synth_xilinx.cc b/techlibs/xilinx/synth_xilinx.cc index a293081f1..567859f62 100644 --- a/techlibs/xilinx/synth_xilinx.cc +++ b/techlibs/xilinx/synth_xilinx.cc @@ -25,6 +25,9 @@ USING_YOSYS_NAMESPACE PRIVATE_NAMESPACE_BEGIN +#define XC7_WIRE_DELAY "300" // Number with which ABC will map a 6-input gate + // to one LUT6 (instead of a LUT5 + LUT2) + struct SynthXilinxPass : public ScriptPass { SynthXilinxPass() : ScriptPass("synth_xilinx", "synthesis for Xilinx FPGAs") { } @@ -58,6 +61,9 @@ struct SynthXilinxPass : public ScriptPass log(" generate an output netlist (and BLIF file) suitable for VPR\n"); log(" (this feature is experimental and incomplete)\n"); log("\n"); + log(" -nocarry\n"); + log(" disable inference of carry chains\n"); + log("\n"); log(" -nobram\n"); log(" disable inference of block rams\n"); log("\n"); @@ -67,6 +73,9 @@ struct SynthXilinxPass : public ScriptPass log(" -nosrl\n"); log(" disable inference of shift registers\n"); log("\n"); + log(" -nomux\n"); + log(" disable inference of wide multiplexers\n"); + log("\n"); log(" -run <from_label>:<to_label>\n"); log(" only run the commands between the labels (see below). an empty\n"); log(" from label is synonymous to 'begin', and empty to label is\n"); @@ -78,26 +87,32 @@ struct SynthXilinxPass : public ScriptPass log(" -retime\n"); log(" run 'abc' with -dff option\n"); log("\n"); + log(" -abc9\n"); + log(" use new ABC9 flow (EXPERIMENTAL)\n"); + log("\n"); log("\n"); log("The following commands are executed by this synthesis command:\n"); help_script(); log("\n"); } - std::string top_opt, edif_file, blif_file, arch; - bool flatten, retime, vpr, nobram, nodram, nosrl; + std::string top_opt, edif_file, blif_file, abc, arch; + bool flatten, retime, vpr, nocarry, nobram, nodram, nosrl, nomux; void clear_flags() YS_OVERRIDE { top_opt = "-auto-top"; edif_file.clear(); blif_file.clear(); + abc = "abc"; flatten = false; retime = false; vpr = false; + nocarry = false; nobram = false; nodram = false; nosrl = false; + nomux = false; arch = "xc7"; } @@ -145,6 +160,10 @@ struct SynthXilinxPass : public ScriptPass vpr = true; continue; } + if (args[argidx] == "-nocarry") { + nocarry = true; + continue; + } if (args[argidx] == "-nobram") { nobram = true; continue; @@ -157,6 +176,14 @@ struct SynthXilinxPass : public ScriptPass nosrl = true; continue; } + if (args[argidx] == "-nomux") { + nomux = true; + continue; + } + if (args[argidx] == "-abc9") { + abc = "abc9"; + continue; + } break; } extra_args(args, argidx, design); @@ -179,9 +206,9 @@ struct SynthXilinxPass : public ScriptPass { if (check_label("begin")) { if (vpr) - run("read_verilog -lib -D_EXPLICIT_CARRY +/xilinx/cells_sim.v"); + run("read_verilog -lib -D _ABC -D_EXPLICIT_CARRY +/xilinx/cells_sim.v"); else - run("read_verilog -lib +/xilinx/cells_sim.v"); + run("read_verilog -lib -D _ABC +/xilinx/cells_sim.v"); run("read_verilog -lib +/xilinx/cells_xtra.v"); @@ -191,15 +218,40 @@ struct SynthXilinxPass : public ScriptPass run(stringf("hierarchy -check %s", top_opt.c_str())); } - if (check_label("flatten", "(with '-flatten' only)")) { - if (flatten || help_mode) { - run("proc"); - run("flatten"); - } - } - if (check_label("coarse")) { - run("synth -run coarse"); + run("proc"); + if (flatten || help_mode) + run("flatten", "(with -flatten only)"); + run("opt_expr"); + run("opt_clean"); + run("check"); + run("opt"); + // FIXME + //run("wreduce"); + run("peepopt"); + run("opt_clean"); + run("alumacc"); + run("share"); + run("opt"); + run("fsm"); + run("opt -fast"); + run("memory -nomap"); + run("opt_clean"); + + //if (!nomux || help_mode) + // run("muxpack", "(skip if '-nomux')"); + + // shregmap -tech xilinx can cope with $shiftx and $mux + // cells for identifying variable-length shift registers, + // so attempt to convert $pmux-es to the former + // Also: wide multiplexer inference benefits from this too + if (!(nosrl && nomux) || help_mode) + run("pmux2shiftx", "(skip if '-nosrl' and '-nomux')"); + + // Run a number of peephole optimisations, including one + // that optimises $mul cells driving $shiftx's B input + // and that aids wide mux analysis + run("peepopt"); } if (check_label("bram", "(skip if '-nobram')")) { @@ -217,31 +269,41 @@ struct SynthXilinxPass : public ScriptPass } if (check_label("fine")) { - // shregmap -tech xilinx can cope with $shiftx and $mux - // cells for identifiying variable-length shift registers, - // so attempt to convert $pmux-es to the former - if (!nosrl || help_mode) - run("pmux2shiftx", "(skip if '-nosrl')"); - - run("opt -fast -full"); + run("opt -fast"); run("memory_map"); run("dffsr2dff"); run("dff2dffe"); + if (!nomux || help_mode) { + run("simplemap t:$mux", " (skip if -nomux)"); + // FIXME: Must specify mux4, even if we don't need it, + // otherwise it will use mux8 as mux4 + run("muxcover -mux4=150 -mux8=200 -mux16=250 -dmux=0", "(skip if -nomux)"); + } run("opt -full"); if (!nosrl || help_mode) { // shregmap operates on bit-level flops, not word-level, // so break those down here - run("simplemap t:$dff t:$dffe", "(skip if '-nosrl')"); + run("simplemap t:$dff t:$dffe", " (skip if '-nosrl')"); // shregmap with '-tech xilinx' infers variable length shift regs run("shregmap -tech xilinx -minlen 3", "(skip if '-nosrl')"); } - if (!vpr || help_mode) - run("techmap -map +/techmap.v -map +/xilinx/arith_map.v"); - else - run("techmap -map +/techmap.v +/xilinx/arith_map.v -D _EXPLICIT_CARRY"); - + std::string techmap_files = " -map +/techmap.v"; + if (help_mode) + techmap_files += " [-map +/xilinx/mux_map.v]"; + else if (!nomux) + techmap_files += " -map +/xilinx/mux_map.v"; + if (help_mode) + techmap_files += " [-map +/xilinx/arith_map.v]"; + else if (!nocarry) { + techmap_files += " -map +/xilinx/arith_map.v"; + if (vpr) + techmap_files += " -D _EXPLICIT_CARRY"; + else if (abc == "abc9") + techmap_files += " -D _CLB_CARRY"; + } + run("techmap " + techmap_files); run("opt -fast"); } @@ -251,11 +313,15 @@ struct SynthXilinxPass : public ScriptPass } if (check_label("map_luts")) { - if (help_mode) - run("abc -luts 2:2,3,6:5,10,20 [-dff]"); + run("opt_expr -mux_undef"); + if (abc == "abc9") + run(abc + " -lut +/xilinx/abc_xc7.lut -box +/xilinx/abc_xc7.box -W " + XC7_WIRE_DELAY + string(retime ? " -dff" : "")); + else if (help_mode) + run(abc + " -luts 2:2,3,6:5,10,20 [-dff]"); else - run("abc -luts 2:2,3,6:5,10,20" + string(retime ? " -dff" : "")); + run(abc + " -luts 2:2,3,6:5,10,20" + string(retime ? " -dff" : "")); run("clean"); + // This shregmap call infers fixed length shift registers after abc // has performed any necessary retiming if (!nosrl || help_mode) |