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-rw-r--r--techlibs/xilinx/synth_xilinx.cc148
1 files changed, 119 insertions, 29 deletions
diff --git a/techlibs/xilinx/synth_xilinx.cc b/techlibs/xilinx/synth_xilinx.cc
index a293081f1..69b1580b8 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 +73,11 @@ struct SynthXilinxPass : public ScriptPass
log(" -nosrl\n");
log(" disable inference of shift registers\n");
log("\n");
+ log(" -minmuxf <int>\n");
+ log(" enable inference of hard multiplexer resources (MuxFx) for muxes at or\n");
+ log(" above this number of inputs (minimum value 5).\n");
+ log(" default: 0 (no inference)\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");
@@ -78,27 +89,34 @@ 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;
+ int minmuxf;
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;
arch = "xc7";
+ minmuxf = 0;
}
void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
@@ -145,6 +163,10 @@ struct SynthXilinxPass : public ScriptPass
vpr = true;
continue;
}
+ if (args[argidx] == "-nocarry") {
+ nocarry = true;
+ continue;
+ }
if (args[argidx] == "-nobram") {
nobram = true;
continue;
@@ -157,6 +179,14 @@ struct SynthXilinxPass : public ScriptPass
nosrl = true;
continue;
}
+ if (args[argidx] == "-minmuxf" && argidx+1 < args.size()) {
+ minmuxf = atoi(args[++argidx].c_str());
+ continue;
+ }
+ if (args[argidx] == "-abc9") {
+ abc = "abc9";
+ continue;
+ }
break;
}
extra_args(args, argidx, design);
@@ -164,6 +194,9 @@ struct SynthXilinxPass : public ScriptPass
if (arch != "xcup" && arch != "xcu" && arch != "xc7" && arch != "xc6s")
log_cmd_error("Invalid Xilinx -arch setting: %s\n", arch.c_str());
+ if (minmuxf != 0 && minmuxf < 5)
+ log_cmd_error("-minmuxf value must be 0 or >= 5.\n");
+
if (!design->full_selection())
log_cmd_error("This command only operates on fully selected designs!\n");
@@ -179,9 +212,9 @@ 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 -icells -D _ABC -D_EXPLICIT_CARRY +/xilinx/cells_sim.v");
else
- run("read_verilog -lib +/xilinx/cells_sim.v");
+ run("read_verilog -lib -icells -D _ABC +/xilinx/cells_sim.v");
run("read_verilog -lib +/xilinx/cells_xtra.v");
@@ -191,15 +224,37 @@ 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");
+ if (help_mode)
+ run("wreduce [c:* t:$mux %d]", "(selection for '-minmuxf' only)");
+ else
+ run("wreduce" + std::string(minmuxf > 0 ? " c:* t:$mux %d" : ""));
+ run("peepopt");
+ run("opt_clean");
+ run("alumacc");
+ run("share");
+ run("opt");
+ run("fsm");
+ run("opt -fast");
+ run("memory -nomap");
+ run("opt_clean");
+
+ if (minmuxf > 0 || help_mode)
+ run("muxpack", " ('-minmuxf' only)");
+
+ // 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 && minmuxf == 0) || help_mode)
+ run("pmux2shiftx", "(skip if '-nosrl' and '-minmuxf' < 5)");
}
if (check_label("bram", "(skip if '-nobram')")) {
@@ -217,45 +272,80 @@ 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 $pmux-es to the former
- if (!nosrl || help_mode)
- run("pmux2shiftx", "(skip if '-nosrl')");
-
- run("opt -fast -full");
+ run("opt -fast");
run("memory_map");
run("dffsr2dff");
run("dff2dffe");
+ if (minmuxf > 0 || help_mode) {
+ run("simplemap t:$mux", " ('-minmuxf' only)");
+ if (minmuxf > 0 || help_mode) {
+ std::string muxcover_args = " -dmux=0";
+ switch (minmuxf) {
+ // NB: Cost of mux2 is 100; mux8 should cost between 3 and 4
+ // of those so that 4:1 muxes and below are implemented
+ // out of mux2s
+ case 5: muxcover_args += " -mux8=350 -mux16=400"; break;
+ case 6: muxcover_args += " -mux8=450 -mux16=500"; break;
+ case 7: muxcover_args += " -mux8=550 -mux16=600"; break;
+ case 8: muxcover_args += " -mux8=650 -mux16=700"; break;
+ case 9: muxcover_args += " -mux16=750"; break;
+ case 10: muxcover_args += " -mux16=850"; break;
+ case 11: muxcover_args += " -mux16=950"; break;
+ case 12: muxcover_args += " -mux16=1050"; break;
+ case 13: muxcover_args += " -mux16=1150"; break;
+ case 14: muxcover_args += " -mux16=1250"; break;
+ case 15: muxcover_args += " -mux16=1350"; break;
+ default: muxcover_args += " -mux16=1450"; break;
+ }
+ run("muxcover " + muxcover_args, "('-minmuxf' only)");
+ }
+ }
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_args = " -map +/techmap.v";
+ if (help_mode)
+ techmap_args += " [-map +/xilinx/mux_map.v]";
+ else if (minmuxf > 0)
+ techmap_args += stringf(" -D MIN_MUX_INPUTS=%d -map +/xilinx/mux_map.v", minmuxf);
+ if (help_mode)
+ techmap_args += " [-map +/xilinx/arith_map.v]";
+ else if (!nocarry) {
+ techmap_args += " -map +/xilinx/arith_map.v";
+ if (vpr)
+ techmap_args += " -D _EXPLICIT_CARRY";
+ else if (abc == "abc9")
+ techmap_args += " -D _CLB_CARRY";
+ }
+ run("techmap " + techmap_args);
run("opt -fast");
}
if (check_label("map_cells")) {
- run("techmap -map +/techmap.v -map +/xilinx/cells_map.v");
+ std::string techmap_args = "-map +/techmap.v -D _ABC -map +/xilinx/cells_map.v";
+ if (minmuxf > 0)
+ techmap_args += stringf(" -D MIN_MUX_INPUTS=%d", minmuxf);
+ run("techmap " + techmap_args);
run("clean");
}
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)
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-06 10:34:31 +0000