From 687521dbd7ca384372f65ffb7b680a471d09b16a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joachim=20Stro=CC=88mbergson?= <joachim@secworks.se>
Date: Mon, 15 Jun 2015 17:54:13 +0200
Subject: Fixed the carry registers.

---
 src/rtl/montprod.v | 54 +++++++++++++++++++++++++++---------------------------
 1 file changed, 27 insertions(+), 27 deletions(-)

(limited to 'src/rtl')

diff --git a/src/rtl/montprod.v b/src/rtl/montprod.v
index de5e4c0..1b9346f 100644
--- a/src/rtl/montprod.v
+++ b/src/rtl/montprod.v
@@ -132,13 +132,13 @@ module montprod(
   reg [07 : 0] word_index_prev_reg; //register of what word was read previously (result address to emit)
   reg [07 : 0] length_m1;
 
-  reg          add_carry_in_sa;
-  reg          add_carry_new_sa;
-  reg          add_carry_in_sm;
-  reg          add_carry_new_sm;
+  reg          add_carry_in_sa_reg;
+  reg          add_carry_in_sa_new;
+  reg          add_carry_in_sm_reg;
+  reg          add_carry_in_sm_new;
 
-  reg          shr_carry_in;
-  reg          shr_carry_new;
+  reg          shr_carry_in_reg;
+  reg          shr_carry_in_new;
 
   reg          reset_word_index_LSW;
   reg          reset_word_index_MSW;
@@ -187,7 +187,7 @@ module montprod(
   adder32 s_adder_sa(
                      .a(s_mem_read_data),
                      .b(opa_data),
-                     .carry_in(add_carry_in_sa),
+                     .carry_in(add_carry_in_sa_reg),
                      .sum(add_result_sa),
                      .carry_out(add_carry_out_sa)
                     );
@@ -195,16 +195,16 @@ module montprod(
   adder32 s_adder_sm(
                      .a(s_mem_read_data),
                      .b(opm_data),
-                     .carry_in(add_carry_in_sm),
+                     .carry_in(add_carry_in_sm_reg),
                      .sum(add_result_sm),
                      .carry_out(add_carry_out_sm)
                     );
 
   shr32 shifter(
-                .a( s_mem_read_data ),
-                .carry_in( shr_carry_in ),
-                .adiv2( shr_adiv2 ),
-                .carry_out( shr_carry_out )
+                .a(s_mem_read_data),
+                .carry_in(shr_carry_in_reg),
+                .adiv2(shr_adiv2),
+                .carry_out(shr_carry_out)
                );
 
 
@@ -223,9 +223,9 @@ module montprod(
           loop_counter_reg    <= 13'h0;
           word_index_reg      <= 8'h0;
           word_index_prev_reg <= 8'h0;
-          add_carry_in_sa     <= 1'b0;
-          add_carry_in_sm     <= 1'b0;
-          shr_carry_in        <= 1'b0;
+          add_carry_in_sa_reg <= 1'b0;
+          add_carry_in_sm_reg <= 1'b0;
+          shr_carry_in_reg    <= 1'b0;
           b_reg               <= 1'b0;
           q_reg               <= 1'b0;
           s_mux_reg           <= SMUX_0;
@@ -242,9 +242,9 @@ module montprod(
           word_index_reg      <= word_index_new;
           word_index_prev_reg <= word_index_reg;
 
-          shr_carry_in    <= shr_carry_new;
-          add_carry_in_sa <= add_carry_new_sa;
-          add_carry_in_sm <= add_carry_new_sm;
+          shr_carry_in_reg    <= shr_carry_in_new;
+          add_carry_in_sa_reg <= add_carry_in_sa_new;
+          add_carry_in_sm_reg <= add_carry_in_sm_new;
 
           B_bit_index_reg <= B_bit_index;
           q_reg <= q;
@@ -255,13 +255,13 @@ module montprod(
           if (ready_we)
             ready_reg <= ready_new;
 
+          if (loop_counter_we)
+            loop_counter_reg <= loop_counter_new;
+
           if (montprod_ctrl_we)
             begin
                montprod_ctrl_reg <= montprod_ctrl_new;
              end
-
-          if (loop_counter_we)
-            loop_counter_reg <= loop_counter_new;
         end
     end // reg_update
 
@@ -403,7 +403,7 @@ module montprod(
   //----------------------------------------------------------------
   always @*
     begin : s_writer
-      shr_carry_new    = 1'b0;
+      shr_carry_in_new    = 1'b0;
       s_mux_new        = SMUX_0;
       s_mem_we_new  = 1'b0;
 
@@ -440,18 +440,18 @@ module montprod(
           end
       endcase
 
-      add_carry_new_sa = 1'b0;
-      add_carry_new_sm = 1'b0;
+      add_carry_in_sa_new = 1'b0;
+      add_carry_in_sm_new = 1'b0;
 
       case (s_mux_reg)
         SMUX_ADD_SM:
-          add_carry_new_sm = add_carry_out_sm;
+          add_carry_in_sm_new = add_carry_out_sm;
 
         SMUX_ADD_SA:
-          add_carry_new_sa = add_carry_out_sa;
+          add_carry_in_sa_new = add_carry_out_sa;
 
         SMUX_SHR:
-          shr_carry_new = shr_carry_out;
+          shr_carry_in_new = shr_carry_out;
 
         default:
           begin
-- 
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