From 90337c66cc1a644b27a4ed8e188b1aa4e07fea67 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joachim=20Stro=CC=88mbergson?= <joachim@secworks.se>
Date: Thu, 18 Jun 2015 11:16:56 +0200
Subject: Moved s logic mux control to control fsm.

---
 src/rtl/montprod.v | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

(limited to 'src')

diff --git a/src/rtl/montprod.v b/src/rtl/montprod.v
index 8f2d012..465bd70 100644
--- a/src/rtl/montprod.v
+++ b/src/rtl/montprod.v
@@ -332,28 +332,24 @@ module montprod(
   always @*
     begin : s_select_write
       shr_carry_in_new = 1'b0;
-      s_mux_new        = SMUX_0;
       s_mem_we_new     = 1'b0;
       sa_adder_data_in = 32'h0;
 
       case (montprod_ctrl_reg)
         CTRL_INIT_S:
           begin
-            s_mux_new    = SMUX_0; // write 0
             s_mem_we_new = 1'b1;
           end
 
         CTRL_L_CALC_SA:
           begin
             //s = (s + q*M + b*A) >>> 1;, if(b==1) S+= A. Takes (1..length) cycles.
-            s_mux_new    = SMUX_ADD_SA;
             s_mem_we_new = b_reg | q_reg;
           end
 
         CTRL_L_CALC_SDIV2:
           begin
             //s = (s + q*M + b*A) >>> 1; s>>=1.  Takes (1..length) cycles.
-            s_mux_new     = SMUX_SHR;
             s_mem_we_new  = 1'b1;
           end
 
@@ -459,6 +455,8 @@ module montprod(
       b_bit_index_we    = 1'b0;
       bq_we             = 1'b0;
 
+      s_mux_new        = SMUX_0;
+
       reset_word_index_lsw = 1'b0;
       reset_word_index_msw = 1'b0;
 
@@ -483,6 +481,8 @@ module montprod(
 
         CTRL_INIT_S:
           begin
+            s_mux_new    = SMUX_0; // write 0
+
             if (word_index_reg == 8'h0)
               begin
                 loop_ctr_set  = 1'b1;
@@ -517,6 +517,8 @@ module montprod(
 
         CTRL_L_CALC_SA:
           begin
+            s_mux_new    = SMUX_ADD_SA;
+
             if (word_index_reg == 8'h0)
               begin
                 reset_word_index_lsw = 1'b1;
@@ -534,6 +536,8 @@ module montprod(
 
         CTRL_L_CALC_SDIV2:
           begin
+            s_mux_new     = SMUX_SHR;
+
             if (word_index_reg == length_m1)
               begin
                 montprod_ctrl_new = CTRL_L_STALLPIPE_D2;
-- 
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