From da5181a3df6ceed96f1762e4cdaec5cbe3ea23db Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Tue, 5 Mar 2019 19:49:39 -0800
Subject: [PATCH] Improvements in SF2 flow and demo

Signed-off-by: Clifford Wolf <clifford@clifford.at>
---
 examples/igloo2/.gitignore |  1 +
 examples/igloo2/runme.sh   |  2 +-
 techlibs/sf2/sf2_iobs.cc   | 15 ++++++++++-----
 techlibs/sf2/synth_sf2.cc  | 16 +++++++++++++---
 4 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/examples/igloo2/.gitignore b/examples/igloo2/.gitignore
index ea58efc9f..33b7182d3 100644
--- a/examples/igloo2/.gitignore
+++ b/examples/igloo2/.gitignore
@@ -1,3 +1,4 @@
 /netlist.edn
 /netlist.vm
+/example.stp
 /proj
diff --git a/examples/igloo2/runme.sh b/examples/igloo2/runme.sh
index a08894e0a..838f027db 100644
--- a/examples/igloo2/runme.sh
+++ b/examples/igloo2/runme.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 set -ex
-yosys -p 'synth_sf2 -top example -edif netlist.edn -vlog netlist.vm' example.v
+yosys -p 'synth_sf2 -noclkbuf -top example -edif netlist.edn -vlog netlist.vm' example.v
 export LM_LICENSE_FILE=${LM_LICENSE_FILE:-1702@localhost}
 /opt/microsemi/Libero_SoC_v12.0/Libero/bin/libero SCRIPT:libero.tcl
 cp proj/designer/example/export/example.stp .
diff --git a/techlibs/sf2/sf2_iobs.cc b/techlibs/sf2/sf2_iobs.cc
index 27141430c..a85552575 100644
--- a/techlibs/sf2/sf2_iobs.cc
+++ b/techlibs/sf2/sf2_iobs.cc
@@ -33,18 +33,23 @@ struct Sf2IobsPass : public Pass {
 		log("\n");
 		log("Add SF2 I/O buffers to top module IOs as needed.\n");
 		log("\n");
+		log("    -noclkbuf\n");
+		log("        Do not insert clock buffers\n");
+		log("\n");
 	}
 	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
+		bool noclkbuf_mode = false;
+
 		log_header(design, "Executing sf2_iobs pass (insert IO buffers).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
 		{
-			// if (args[argidx] == "-singleton") {
-			// 	singleton_mode = true;
-			// 	continue;
-			// }
+			if (args[argidx] == "-noclkbuf") {
+				noclkbuf_mode = true;
+				continue;
+			}
 			break;
 		}
 		extra_args(args, argidx, design);
@@ -94,7 +99,7 @@ struct Sf2IobsPass : public Pass {
 				if (wire->port_output) {
 					buf_type = "\\OUTBUF";
 					buf_port = "\\D";
-				} else if (clk_bits.count(canonical_bit)) {
+				} else if (clk_bits.count(canonical_bit) && !noclkbuf_mode) {
 					buf_type = "\\CLKBUF";
 					buf_port = "\\Y";
 				} else {
diff --git a/techlibs/sf2/synth_sf2.cc b/techlibs/sf2/synth_sf2.cc
index bdc20456d..b834af07d 100644
--- a/techlibs/sf2/synth_sf2.cc
+++ b/techlibs/sf2/synth_sf2.cc
@@ -63,6 +63,9 @@ struct SynthSf2Pass : public ScriptPass
 		log("    -noiobs\n");
 		log("        run synthesis in \"block mode\", i.e. do not insert IO buffers\n");
 		log("\n");
+		log("    -noclkbuf\n");
+		log("        do not inser clock buffers, only simpe IO buffers\n");
+		log("\n");
 		log("    -retime\n");
 		log("        run 'abc' with -dff option\n");
 		log("\n");
@@ -73,7 +76,7 @@ struct SynthSf2Pass : public ScriptPass
 	}
 
 	string top_opt, edif_file, vlog_file, json_file;
-	bool flatten, retime, iobs;
+	bool flatten, retime, iobs, clkbuf;
 
 	void clear_flags() YS_OVERRIDE
 	{
@@ -84,6 +87,7 @@ struct SynthSf2Pass : public ScriptPass
 		flatten = true;
 		retime = false;
 		iobs = true;
+		clkbuf = true;
 	}
 
 	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
@@ -130,6 +134,10 @@ struct SynthSf2Pass : public ScriptPass
 				iobs = false;
 				continue;
 			}
+			if (args[argidx] == "-noclkbuf") {
+				clkbuf = false;
+				continue;
+			}
 			break;
 		}
 		extra_args(args, argidx, design);
@@ -201,8 +209,10 @@ struct SynthSf2Pass : public ScriptPass
 
 		if (check_label("map_iobs"))
 		{
-			if (iobs || help_mode)
-				run("sf2_iobs", "(unless -noiobs)");
+			if (help_mode)
+				run("sf2_iobs [-noclkbuf]", "(unless -noiobs)");
+			else if (iobs)
+				run(clkbuf ? "sf2_iobs" : "sf2_iobs -noclkbuf");
 			run("clean");
 		}
 
-- 
2.30.2