From c67a63762f6afd7bdc424559d557035ff2b4397c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Joachim=20Stro=CC=88mbergson?= <joachim@secworks.se>
Date: Mon, 5 Oct 2015 13:37:59 +0200
Subject: (1) Minor cleanup. Removed unneeded code blocks and comments. (2)
 Moved debug mux to below reg updates to match structure in other source
 files.

---
 src/rtl/trng.v | 115 +++++++++++++++++++++++----------------------------------
 1 file changed, 47 insertions(+), 68 deletions(-)

(limited to 'src')

diff --git a/src/rtl/trng.v b/src/rtl/trng.v
index 06af515..c74f8b1 100644
--- a/src/rtl/trng.v
+++ b/src/rtl/trng.v
@@ -329,6 +329,44 @@ module trng(
                        );
 
 
+  //----------------------------------------------------------------
+  // reg_update
+  //
+  // Update functionality for all registers in the core.
+  // All registers are positive edge triggered with asynchronous
+  // active low reset.
+  //----------------------------------------------------------------
+  always @ (posedge clk or negedge reset_n)
+    begin
+      if (!reset_n)
+        begin
+          discard_reg            <= 0;
+          test_mode_reg          <= 0;
+          debug_mux_reg          <= DEBUG_CSPRNG;
+          debug_delay_reg        <= DEFAULT_DEBUG_DELAY;
+          debug_delay_ctr_reg    <= 32'h00000000;
+          debug_out_reg          <= 8'h00;
+        end
+      else
+        begin
+          discard_reg            <= discard_new;
+          debug_delay_ctr_reg    <= debug_delay_ctr_new;
+
+          if (debug_out_we)
+            debug_out_reg <= tmp_debug;
+
+          if (test_mode_we)
+            test_mode_reg <= test_mode_new;
+
+          if (debug_mux_we)
+            debug_mux_reg <= debug_mux_new;
+
+          if (debug_delay_we)
+            debug_delay_reg <= debug_delay_new;
+        end
+    end // reg_update
+
+
   //----------------------------------------------------------------
   // core_mux
   //
@@ -379,44 +417,6 @@ module trng(
     end // core_mux
 
 
-  //----------------------------------------------------------------
-  // reg_update
-  //
-  // Update functionality for all registers in the core.
-  // All registers are positive edge triggered with asynchronous
-  // active low reset.
-  //----------------------------------------------------------------
-  always @ (posedge clk or negedge reset_n)
-    begin
-      if (!reset_n)
-        begin
-          discard_reg            <= 0;
-          test_mode_reg          <= 0;
-          debug_mux_reg          <= DEBUG_CSPRNG;
-          debug_delay_reg        <= DEFAULT_DEBUG_DELAY;
-          debug_delay_ctr_reg    <= 32'h00000000;
-          debug_out_reg          <= 8'h00;
-        end
-      else
-        begin
-          discard_reg            <= discard_new;
-          debug_delay_ctr_reg    <= debug_delay_ctr_new;
-
-          if (debug_out_we)
-            debug_out_reg <= tmp_debug;
-
-          if (test_mode_we)
-            test_mode_reg <= test_mode_new;
-
-          if (debug_mux_we)
-            debug_mux_reg <= debug_mux_new;
-
-          if (debug_delay_we)
-            debug_delay_reg <= debug_delay_new;
-        end
-    end // reg_update
-
-
   //----------------------------------------------------------------
   // debug_update_logic
   //
@@ -506,9 +506,7 @@ module trng(
         begin
           if (trng_api_we)
             begin
-              // Write operations.
               case (api_address)
-                // Write operations.
                 ADDR_TRNG_CTRL:
                   begin
                     discard_new   = write_data[TRNG_CTRL_DISCARD_BIT];
@@ -529,61 +527,42 @@ module trng(
                   end
 
                 default:
-                  begin
-                    trng_api_error = 1;
-                  end
+                  trng_api_error = 1;
               endcase // case (address)
             end // if (we)
 
           else
             begin
-              // Read operations.
               case (api_address)
-                // Read operations.
                 ADDR_NAME0:
-                  begin
-                    trng_api_read_data = TRNG_NAME0;
-                  end
+                  trng_api_read_data = TRNG_NAME0;
 
                 ADDR_NAME1:
-                  begin
-                    trng_api_read_data = TRNG_NAME1;
-                  end
+                  trng_api_read_data = TRNG_NAME1;
 
                 ADDR_VERSION:
-                  begin
-                    trng_api_read_data = TRNG_VERSION;
-                  end
+                  trng_api_read_data = TRNG_VERSION;
 
                 ADDR_TRNG_CTRL:
-                  begin
-                    trng_api_read_data = {30'h0000000, test_mode_reg, discard_reg};
-                  end
+                  trng_api_read_data = {30'h0000000, test_mode_reg, discard_reg};
 
                 ADDR_TRNG_STATUS:
                   begin
-
+                    // No error caused by reading status.
                   end
 
                 ADDR_DEBUG_CTRL:
-                  begin
-                    trng_api_read_data = {29'h0000000, debug_mux_new};
-                  end
+                  trng_api_read_data = {29'h0000000, debug_mux_new};
 
                 ADDR_DEBUG_DELAY:
-                  begin
-                    trng_api_read_data = debug_delay_reg;
-                  end
+                  trng_api_read_data = debug_delay_reg;
 
                 default:
-                  begin
-                    trng_api_error = 1;
-                  end
+                  trng_api_error = 1;
               endcase // case (address)
             end
         end
     end // trng_api_logic
-
 endmodule // trng
 
 //======================================================================
-- 
cgit v1.2.3