From: Miodrag Milanovic <mmicko@gmail.com>
Date: Sat, 3 Aug 2019 12:40:23 +0000 (+0200)
Subject: Custom step to add global clock buffers
X-Git-Tag: working-ls180~1116^2~11
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6e210f26fa97fa65c420534f0ec0e26eeb1b078a;p=yosys.git

Custom step to add global clock buffers
---

diff --git a/techlibs/efinix/Makefile.inc b/techlibs/efinix/Makefile.inc
index 3f3394c96..82dfa3cd8 100644
--- a/techlibs/efinix/Makefile.inc
+++ b/techlibs/efinix/Makefile.inc
@@ -1,5 +1,6 @@
 
 OBJS += techlibs/efinix/synth_efinix.o
+OBJS += techlibs/efinix/efinix_gbuf.o
 
 $(eval $(call add_share_file,share/efinix,techlibs/efinix/cells_map.v))
 $(eval $(call add_share_file,share/efinix,techlibs/efinix/arith_map.v))
diff --git a/techlibs/efinix/cells_sim.v b/techlibs/efinix/cells_sim.v
index aaff955a2..2cbf8ae4b 100644
--- a/techlibs/efinix/cells_sim.v
+++ b/techlibs/efinix/cells_sim.v
@@ -33,4 +33,12 @@ module EFX_FF(
    parameter SR_VALUE = 0;
    parameter SR_SYNC_PRIORITY = 0;
    parameter D_POLARITY = 1;
-endmodule
\ No newline at end of file
+endmodule
+
+module EFX_GBUFCE (
+   input CE,
+   input I,
+   output O
+);
+   parameter CE_POLARITY = 1'b1;
+endmodule
diff --git a/techlibs/efinix/efinix_gbuf.cc b/techlibs/efinix/efinix_gbuf.cc
new file mode 100644
index 000000000..50f84c30c
--- /dev/null
+++ b/techlibs/efinix/efinix_gbuf.cc
@@ -0,0 +1,113 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2019  Miodrag Milanovic <miodrag@symbioticeda.com>
+ *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/yosys.h"
+#include "kernel/sigtools.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+static void handle_gbufs(Module *module)
+{
+	SigMap sigmap(module);
+
+	pool<SigBit> clk_bits;
+	dict<SigBit, SigBit> rewrite_bits;
+	vector<pair<Cell*, SigBit>> pad_bits;
+
+	for (auto cell : module->cells())
+	{
+		if (cell->type == "\\EFX_FF") {
+			for (auto bit : sigmap(cell->getPort("\\CLK")))
+				clk_bits.insert(bit);
+		}
+	}
+
+	for (auto wire : vector<Wire*>(module->wires()))
+	{
+		if (!wire->port_input)
+			continue;
+
+		for (int index = 0; index < GetSize(wire); index++)
+		{
+			SigBit bit(wire, index);
+			SigBit canonical_bit = sigmap(bit);
+
+			if (!clk_bits.count(canonical_bit))
+				continue;
+
+			Cell *c = module->addCell(NEW_ID, "\\EFX_GBUFCE");
+			SigBit new_bit = module->addWire(NEW_ID);
+			c->setParam("\\CE_POLARITY", State::S1);
+			c->setPort("\\O", new_bit);
+			c->setPort("\\CE", State::S1);
+			pad_bits.push_back(make_pair(c, bit));
+			rewrite_bits[canonical_bit] = new_bit;
+
+			log("Added %s cell %s for port bit %s.\n", log_id(c->type), log_id(c), log_signal(bit));
+		}
+	}
+
+	auto rewrite_function = [&](SigSpec &s) {
+		for (auto &bit : s) {
+			SigBit canonical_bit = sigmap(bit);
+			if (rewrite_bits.count(canonical_bit))
+				bit = rewrite_bits.at(canonical_bit);
+		}
+	};
+
+	module->rewrite_sigspecs(rewrite_function);
+
+	for (auto &it : pad_bits)
+		it.first->setPort("\\I", it.second);
+}
+
+struct EfinixGbufPass : public Pass {
+	EfinixGbufPass() : Pass("efinix_gbuf", "Efinix: insert global clock buffers") { }
+	void help() YS_OVERRIDE
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    efinix_gbuf [options] [selection]\n");
+		log("\n");
+		log("Add Efinix global clock buffers to top module as needed.\n");
+		log("\n");
+	}
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
+	{
+		log_header(design, "Executing efinix_gbuf pass (insert global clock buffers).\n");
+		
+		size_t argidx;
+		for (argidx = 1; argidx < args.size(); argidx++)
+		{
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		Module *module = design->top_module();
+
+		if (module == nullptr)
+			log_cmd_error("No top module found.\n");
+
+		handle_gbufs(module);		
+	}
+} EfinixGbufPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/techlibs/efinix/synth_efinix.cc b/techlibs/efinix/synth_efinix.cc
index 9c644d363..3f17bafa3 100644
--- a/techlibs/efinix/synth_efinix.cc
+++ b/techlibs/efinix/synth_efinix.cc
@@ -181,6 +181,12 @@ struct SynthEfinixPass : public ScriptPass
 			run("clean");
 		}
 
+		if (check_label("map_gbuf"))
+		{
+			run("efinix_gbuf");
+			run("clean");
+		}
+		
 		if (check_label("check"))
 		{
 			run("hierarchy -check");