From 5fdee952c92c62409ca58e8d18d951dfafed3c92 Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Mon, 5 Sep 2016 22:37:52 +0200
Subject: [PATCH] Added picorv32_pcpi_fast_mul MUL_CLKGATE

---
 picorv32.v | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/picorv32.v b/picorv32.v
index 5b8d021..5f2fd15 100644
--- a/picorv32.v
+++ b/picorv32.v
@@ -1918,7 +1918,8 @@ endmodule
 
 module picorv32_pcpi_fast_mul #(
 	parameter EXTRA_MUL_FFS = 0,
-	parameter EXTRA_INSN_FFS = 0
+	parameter EXTRA_INSN_FFS = 0,
+	parameter MUL_CLKGATE = 0
 ) (
 	input clk, resetn,
 
@@ -1963,9 +1964,13 @@ module picorv32_pcpi_fast_mul #(
 
 	always @(posedge clk) begin
 		pcpi_insn_valid_q <= pcpi_insn_valid;
-		rs1_q <= rs1;
-		rs2_q <= rs2;
-		rd_q <= rd;
+		if (!MUL_CLKGATE || active[0]) begin
+			rs1_q <= rs1;
+			rs2_q <= rs2;
+		end
+		if (!MUL_CLKGATE || active[2]) begin
+			rd_q <= rd;
+		end
 	end
 
 	always @(posedge clk) begin