From 0cac95ea9403befe3dca49621ff577ce13faebf0 Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Wed, 4 Jan 2017 18:12:41 +0100
Subject: [PATCH] Added "check -initdrv"

---
 passes/cmds/check.cc | 85 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 82 insertions(+), 3 deletions(-)

diff --git a/passes/cmds/check.cc b/passes/cmds/check.cc
index b3622cb19..bb8fe6856 100644
--- a/passes/cmds/check.cc
+++ b/passes/cmds/check.cc
@@ -44,6 +44,9 @@ struct CheckPass : public Pass {
 		log("When called with -noinit then this command also checks for wires which have\n");
 		log("the 'init' attribute set.\n");
 		log("\n");
+		log("When called with -initdrv then this command also checks for wires which have\n");
+		log("the 'init' attribute set and aren't driven by a FF cell type.\n");
+		log("\n");
 		log("When called with -assert then the command will produce an error if any\n");
 		log("problems are found in the current design.\n");
 		log("\n");
@@ -52,6 +55,7 @@ struct CheckPass : public Pass {
 	{
 		int counter = 0;
 		bool noinit = false;
+		bool initdrv = false;
 		bool assert_mode = false;
 
 		size_t argidx;
@@ -60,6 +64,10 @@ struct CheckPass : public Pass {
 				noinit = true;
 				continue;
 			}
+			if (args[argidx] == "-initdrv") {
+				initdrv = true;
+				continue;
+			}
 			if (args[argidx] == "-assert") {
 				assert_mode = true;
 				continue;
@@ -70,6 +78,49 @@ struct CheckPass : public Pass {
 
 		log_header(design, "Executing CHECK pass (checking for obvious problems).\n");
 
+		pool<IdString> fftypes;
+		fftypes.insert("$sr");
+		fftypes.insert("$ff");
+		fftypes.insert("$dff");
+		fftypes.insert("$dffe");
+		fftypes.insert("$dffsr");
+		fftypes.insert("$adff");
+		fftypes.insert("$dlatch");
+		fftypes.insert("$dlatchsr");
+		fftypes.insert("$_DFFE_NN_");
+		fftypes.insert("$_DFFE_NP_");
+		fftypes.insert("$_DFFE_PN_");
+		fftypes.insert("$_DFFE_PP_");
+		fftypes.insert("$_DFFSR_NNN_");
+		fftypes.insert("$_DFFSR_NNP_");
+		fftypes.insert("$_DFFSR_NPN_");
+		fftypes.insert("$_DFFSR_NPP_");
+		fftypes.insert("$_DFFSR_PNN_");
+		fftypes.insert("$_DFFSR_PNP_");
+		fftypes.insert("$_DFFSR_PPN_");
+		fftypes.insert("$_DFFSR_PPP_");
+		fftypes.insert("$_DFF_NN0_");
+		fftypes.insert("$_DFF_NN1_");
+		fftypes.insert("$_DFF_NP0_");
+		fftypes.insert("$_DFF_NP1_");
+		fftypes.insert("$_DFF_N_");
+		fftypes.insert("$_DFF_PN0_");
+		fftypes.insert("$_DFF_PN1_");
+		fftypes.insert("$_DFF_PP0_");
+		fftypes.insert("$_DFF_PP1_");
+		fftypes.insert("$_DFF_P_");
+		fftypes.insert("$_DLATCHSR_NNN_");
+		fftypes.insert("$_DLATCHSR_NNP_");
+		fftypes.insert("$_DLATCHSR_NPN_");
+		fftypes.insert("$_DLATCHSR_NPP_");
+		fftypes.insert("$_DLATCHSR_PNN_");
+		fftypes.insert("$_DLATCHSR_PNP_");
+		fftypes.insert("$_DLATCHSR_PPN_");
+		fftypes.insert("$_DLATCHSR_PPP_");
+		fftypes.insert("$_DLATCH_N_");
+		fftypes.insert("$_DLATCH_P_");
+		fftypes.insert("$_FF_");
+
 		for (auto module : design->selected_whole_modules_warn())
 		{
 			if (module->has_processes_warn())
@@ -109,6 +160,8 @@ struct CheckPass : public Pass {
 						if (bit.wire) wire_drivers_count[bit]++;
 			}
 
+			pool<SigBit> init_bits;
+
 			for (auto wire : module->wires()) {
 				if (wire->port_input) {
 					SigSpec sig = sigmap(wire);
@@ -121,9 +174,15 @@ struct CheckPass : public Pass {
 				if (wire->port_input && !wire->port_output)
 					for (auto bit : sigmap(wire))
 						if (bit.wire) wire_drivers_count[bit]++;
-				if (noinit && wire->attributes.count("\\init")) {
-					log_warning("Wire %s.%s has an unprocessed 'init' attribute.\n", log_id(module), log_id(wire));
-					counter++;
+				if (wire->attributes.count("\\init")) {
+					Const initval = wire->attributes.at("\\init");
+					for (int i = 0; i < GetSize(initval) && i < GetSize(wire); i++)
+						if (initval[i] == State::S0 || initval[i] == State::S1)
+							init_bits.insert(sigmap(SigBit(wire, i)));
+					if (noinit) {
+						log_warning("Wire %s.%s has an unprocessed 'init' attribute.\n", log_id(module), log_id(wire));
+						counter++;
+					}
 				}
 			}
 
@@ -150,6 +209,26 @@ struct CheckPass : public Pass {
 				log_warning("%s", message.c_str());
 				counter++;
 			}
+
+			if (initdrv)
+			{
+				for (auto cell : module->cells())
+				{
+					if (fftypes.count(cell->type) == 0)
+						continue;
+
+					for (auto bit : sigmap(cell->getPort("\\Q")))
+						init_bits.erase(bit);
+				}
+
+				SigSpec init_sig(init_bits);
+				init_sig.sort_and_unify();
+
+				for (auto chunk : init_sig.chunks()) {
+					log_warning("Wire %s.%s has 'init' attribute and is not driven by an FF cell.\n", log_id(module), log_signal(chunk));
+					counter++;
+				}
+			}
 		}
 
 		log("found and reported %d problems.\n", counter);
-- 
2.30.2