Cleaned up the code as part of fixing issues found during the audit.

2 files changed, 90 insertions, 862 deletions

diff --git a/src/rtl/sha512.v b/src/rtl/sha512.v
index a0e5f9f..085783b 100644
--- a/src/rtl/sha512.v
+++ b/src/rtl/sha512.v
@@ -75,36 +75,6 @@ module sha512(
   parameter ADDR_WORK_FACTOR_NUM = 8'h0a;
 
   parameter ADDR_BLOCK0          = 8'h10;
-  parameter ADDR_BLOCK1          = 8'h11;
-  parameter ADDR_BLOCK2          = 8'h12;
-  parameter ADDR_BLOCK3          = 8'h13;
-  parameter ADDR_BLOCK4          = 8'h14;
-  parameter ADDR_BLOCK5          = 8'h15;
-  parameter ADDR_BLOCK6          = 8'h16;
-  parameter ADDR_BLOCK7          = 8'h17;
-  parameter ADDR_BLOCK8          = 8'h18;
-  parameter ADDR_BLOCK9          = 8'h19;
-  parameter ADDR_BLOCK10         = 8'h1a;
-  parameter ADDR_BLOCK11         = 8'h1b;
-  parameter ADDR_BLOCK12         = 8'h1c;
-  parameter ADDR_BLOCK13         = 8'h1d;
-  parameter ADDR_BLOCK14         = 8'h1e;
-  parameter ADDR_BLOCK15         = 8'h1f;
-  parameter ADDR_BLOCK16         = 8'h20;
-  parameter ADDR_BLOCK17         = 8'h21;
-  parameter ADDR_BLOCK18         = 8'h22;
-  parameter ADDR_BLOCK19         = 8'h23;
-  parameter ADDR_BLOCK20         = 8'h24;
-  parameter ADDR_BLOCK21         = 8'h25;
-  parameter ADDR_BLOCK22         = 8'h26;
-  parameter ADDR_BLOCK23         = 8'h27;
-  parameter ADDR_BLOCK24         = 8'h28;
-  parameter ADDR_BLOCK25         = 8'h29;
-  parameter ADDR_BLOCK26         = 8'h2a;
-  parameter ADDR_BLOCK27         = 8'h2b;
-  parameter ADDR_BLOCK28         = 8'h2c;
-  parameter ADDR_BLOCK29         = 8'h2d;
-  parameter ADDR_BLOCK30         = 8'h2e;
   parameter ADDR_BLOCK31         = 8'h2f;
 
   parameter ADDR_DIGEST0         = 8'h40;
@@ -126,7 +96,7 @@ module sha512(
 
   parameter CORE_NAME0         = 32'h73686132; // "sha2"
   parameter CORE_NAME1         = 32'h2d353132; // "-512"
-  parameter CORE_VERSION       = 32'h302e3830; // "0.80"
+  parameter CORE_VERSION       = 32'h302e3831; // "0.81"
 
   parameter MODE_SHA_512_224   = 2'h0;
   parameter MODE_SHA_512_256   = 2'h1;
@@ -162,70 +132,8 @@ module sha512(
 
   reg ready_reg;
 
-  reg [31 : 0] block0_reg;
-  reg          block0_we;
-  reg [31 : 0] block1_reg;
-  reg          block1_we;
-  reg [31 : 0] block2_reg;
-  reg          block2_we;
-  reg [31 : 0] block3_reg;
-  reg          block3_we;
-  reg [31 : 0] block4_reg;
-  reg          block4_we;
-  reg [31 : 0] block5_reg;
-  reg          block5_we;
-  reg [31 : 0] block6_reg;
-  reg          block6_we;
-  reg [31 : 0] block7_reg;
-  reg          block7_we;
-  reg [31 : 0] block8_reg;
-  reg          block8_we;
-  reg [31 : 0] block9_reg;
-  reg          block9_we;
-  reg [31 : 0] block10_reg;
-  reg          block10_we;
-  reg [31 : 0] block11_reg;
-  reg          block11_we;
-  reg [31 : 0] block12_reg;
-  reg          block12_we;
-  reg [31 : 0] block13_reg;
-  reg          block13_we;
-  reg [31 : 0] block14_reg;
-  reg          block14_we;
-  reg [31 : 0] block15_reg;
-  reg          block15_we;
-  reg [31 : 0] block16_reg;
-  reg          block16_we;
-  reg [31 : 0] block17_reg;
-  reg          block17_we;
-  reg [31 : 0] block18_reg;
-  reg          block18_we;
-  reg [31 : 0] block19_reg;
-  reg          block19_we;
-  reg [31 : 0] block20_reg;
-  reg          block20_we;
-  reg [31 : 0] block21_reg;
-  reg          block21_we;
-  reg [31 : 0] block22_reg;
-  reg          block22_we;
-  reg [31 : 0] block23_reg;
-  reg          block23_we;
-  reg [31 : 0] block24_reg;
-  reg          block24_we;
-  reg [31 : 0] block25_reg;
-  reg          block25_we;
-  reg [31 : 0] block26_reg;
-  reg          block26_we;
-  reg [31 : 0] block27_reg;
-  reg          block27_we;
-  reg [31 : 0] block28_reg;
-  reg          block28_we;
-  reg [31 : 0] block29_reg;
-  reg          block29_we;
-  reg [31 : 0] block30_reg;
-  reg          block30_we;
-  reg [31 : 0] block31_reg;
-  reg          block31_we;
+  reg [31 : 0] block_reg [0 : 31];
+  reg          block_we;
 
   reg [511 : 0] digest_reg;
   reg           digest_valid_reg;
@@ -234,16 +142,13 @@ module sha512(
   //----------------------------------------------------------------
   // Wires.
   //----------------------------------------------------------------
-  wire            core_init;
-  wire            core_next;
-  wire [1 : 0]    core_mode;
-  wire            core_work_factor;
-  wire [31 : 0]   core_work_factor_num;
   wire            core_ready;
   wire [1023 : 0] core_block;
   wire [511 : 0]  core_digest;
   wire            core_digest_valid;
 
+  reg [4 : 0]     block_addr;
+
   reg             state00_we;
   reg             state01_we;
   reg             state02_we;
@@ -261,7 +166,6 @@ module sha512(
   reg             state14_we;
   reg             state15_we;
 
-
   reg [31 : 0]    tmp_read_data;
   reg             tmp_error;
 
@@ -269,22 +173,14 @@ module sha512(
   //----------------------------------------------------------------
   // Concurrent connectivity for ports etc.
   //----------------------------------------------------------------
-  assign core_init = init_reg;
-
-  assign core_next = next_reg;
-
-  assign core_mode = mode_reg;
-
-  assign core_work_factor = work_factor_reg;
-  assign core_work_factor_num = work_factor_num_reg;
-
-  assign core_block = {block0_reg,  block1_reg,  block2_reg,  block3_reg,  block4_reg,
-                       block5_reg,  block6_reg,  block7_reg,  block8_reg,  block9_reg,
-                       block10_reg, block11_reg, block12_reg, block13_reg, block14_reg,
-                       block15_reg, block16_reg, block17_reg, block18_reg, block19_reg,
-                       block20_reg, block21_reg, block22_reg, block23_reg, block24_reg,
-                       block25_reg, block26_reg, block27_reg, block28_reg, block29_reg,
-                       block30_reg, block31_reg};
+  assign core_block = {block_reg[00], block_reg[01], block_reg[02], block_reg[03],
+                       block_reg[04], block_reg[05], block_reg[06], block_reg[07],
+                       block_reg[08], block_reg[09], block_reg[10], block_reg[11],
+                       block_reg[12], block_reg[13], block_reg[14], block_reg[15],
+                       block_reg[16], block_reg[17], block_reg[18], block_reg[19],
+                       block_reg[20], block_reg[21], block_reg[22], block_reg[23],
+                       block_reg[24], block_reg[25], block_reg[26], block_reg[27],
+                       block_reg[28], block_reg[29], block_reg[30], block_reg[31]};
 
   assign read_data = tmp_read_data;
   assign error     = tmp_error;
@@ -297,12 +193,12 @@ module sha512(
                    .clk(clk),
                    .reset_n(reset_n),
 
-                   .init(core_init),
-                   .next(core_next),
-                   .mode(core_mode),
+                   .init(init_reg),
+                   .next(next_reg),
+                   .mode(mode_reg),
 
-                   .work_factor(core_work_factor),
-                   .work_factor_num(core_work_factor_num),
+                   .work_factor(work_factor_reg),
+                   .work_factor_num(work_factor_num_reg),
 
                    .block(core_block),
 
@@ -339,9 +235,14 @@ module sha512(
   // active low reset. All registers have write enable.
   //----------------------------------------------------------------
   always @ (posedge clk or negedge reset_n)
-    begin
+    begin : reg_update
+      integer i;
+
       if (!reset_n)
         begin
+          for (i = 0 ; i < 32 ; i = i + 1)
+            block_reg[i] <= 32'h0;
+
           init_reg            <= 1'h0;
           next_reg            <= 1'h0;
           mode_reg            <= MODE_SHA_512;
@@ -350,274 +251,33 @@ module sha512(
           ready_reg           <= 1'h0;
           digest_reg          <= 512'h0;
           digest_valid_reg    <= 1'h0;
-          block0_reg          <= 32'h0;
-          block1_reg          <= 32'h0;
-          block2_reg          <= 32'h0;
-          block3_reg          <= 32'h0;
-          block4_reg          <= 32'h0;
-          block5_reg          <= 32'h0;
-          block6_reg          <= 32'h0;
-          block7_reg          <= 32'h0;
-          block8_reg          <= 32'h0;
-          block9_reg          <= 32'h0;
-          block10_reg         <= 32'h0;
-          block11_reg         <= 32'h0;
-          block12_reg         <= 32'h0;
-          block13_reg         <= 32'h0;
-          block14_reg         <= 32'h0;
-          block15_reg         <= 32'h0;
-          block16_reg         <= 32'h0;
-          block17_reg         <= 32'h0;
-          block18_reg         <= 32'h0;
-          block19_reg         <= 32'h0;
-          block20_reg         <= 32'h0;
-          block21_reg         <= 32'h0;
-          block22_reg         <= 32'h0;
-          block23_reg         <= 32'h0;
-          block24_reg         <= 32'h0;
-          block25_reg         <= 32'h0;
-          block26_reg         <= 32'h0;
-          block27_reg         <= 32'h0;
-          block28_reg         <= 32'h0;
-          block29_reg         <= 32'h0;
-          block30_reg         <= 32'h0;
-          block31_reg         <= 32'h0;
         end
       else
         begin
           ready_reg        <= core_ready;
           digest_valid_reg <= core_digest_valid;
-
-          if (init_we)
-            begin
-              init_reg <= init_new;
-            end
-
-          if (next_we)
-            begin
-              next_reg <= next_new;
-            end
+          init_reg         <= init_new;
+          next_reg         <= next_new;
 
           if (mode_we)
-            begin
-              mode_reg <= mode_new;
-            end
+            mode_reg <= mode_new;
 
           if (work_factor_we)
-            begin
-              work_factor_reg <= work_factor_new;
-            end
+            work_factor_reg <= work_factor_new;
 
           if (work_factor_num_we)
-            begin
-              work_factor_num_reg <= write_data;
-            end
+            work_factor_num_reg <= write_data;
 
           if (core_digest_valid)
-            begin
-              digest_reg <= core_digest;
-            end
-
-          if (block0_we)
-            begin
-              block0_reg <= write_data;
-            end
-
-          if (block1_we)
-            begin
-              block1_reg <= write_data;
-            end
-
-          if (block2_we)
-            begin
-              block2_reg <= write_data;
-            end
-
-          if (block3_we)
-            begin
-              block3_reg <= write_data;
-            end
-
-          if (block4_we)
-            begin
-              block4_reg <= write_data;
-            end
-
-          if (block5_we)
-            begin
-              block5_reg <= write_data;
-            end
-
-          if (block6_we)
-            begin
-              block6_reg <= write_data;
-            end
-
-          if (block7_we)
-            begin
-              block7_reg <= write_data;
-            end
-
-          if (block8_we)
-            begin
-              block8_reg <= write_data;
-            end
-
-          if (block9_we)
-            begin
-              block9_reg <= write_data;
-            end
-
-          if (block10_we)
-            begin
-              block10_reg <= write_data;
-            end
-
-          if (block11_we)
-            begin
-              block11_reg <= write_data;
-            end
-
-          if (block12_we)
-            begin
-              block12_reg <= write_data;
-            end
-
-          if (block13_we)
-            begin
-              block13_reg <= write_data;
-            end
-
-          if (block14_we)
-            begin
-              block14_reg <= write_data;
-            end
-
-          if (block15_we)
-            begin
-              block15_reg <= write_data;
-            end
-
-          if (block16_we)
-            begin
-              block16_reg <= write_data;
-            end
-
-          if (block17_we)
-            begin
-              block17_reg <= write_data;
-            end
-
-          if (block18_we)
-            begin
-              block18_reg <= write_data;
-            end
-
-          if (block19_we)
-            begin
-              block19_reg <= write_data;
-            end
-
-          if (block20_we)
-            begin
-              block20_reg <= write_data;
-            end
-
-          if (block21_we)
-            begin
-              block21_reg <= write_data;
-            end
-
-          if (block22_we)
-            begin
-              block22_reg <= write_data;
-            end
-
-          if (block23_we)
-            begin
-              block23_reg <= write_data;
-            end
-
-          if (block24_we)
-            begin
-              block24_reg <= write_data;
-            end
-
-          if (block25_we)
-            begin
-              block25_reg <= write_data;
-            end
-
-          if (block26_we)
-            begin
-              block26_reg <= write_data;
-            end
-
-          if (block27_we)
-            begin
-              block27_reg <= write_data;
-            end
-
-          if (block28_we)
-            begin
-              block28_reg <= write_data;
-            end
-
-          if (block29_we)
-            begin
-              block29_reg <= write_data;
-            end
-
-          if (block30_we)
-            begin
-              block30_reg <= write_data;
-            end
+            digest_reg <= core_digest;
 
-          if (block31_we)
-            begin
-              block31_reg <= write_data;
-            end
+          if (block_we)
+            block_reg[block_addr] <= write_data;
         end
     end // reg_update
 
 
   //----------------------------------------------------------------
-  // flag_reset
-  //
-  // Logic to reset init and next flags that has been set.
-  //----------------------------------------------------------------
-  always @*
-    begin : flag_reset
-      init_new = 0;
-      init_we  = 0;
-      next_new = 0;
-      next_we  = 0;
-
-      if (init_set)
-        begin
-          init_new = 1;
-          init_we  = 1;
-        end
-      else if (init_reg)
-        begin
-          init_new = 0;
-          init_we  = 1;
-        end
-
-      if (next_set)
-        begin
-          next_new = 1;
-          next_we  = 1;
-        end
-      else if (next_reg)
-        begin
-          next_new = 0;
-          next_we  = 1;
-        end
-    end
-
-
-  //----------------------------------------------------------------
   // api_logic
   //
   // Implementation of the api logic. If cs is enabled will either
@@ -625,78 +285,51 @@ module sha512(
   //----------------------------------------------------------------
   always @*
     begin : api_logic
-      init_set           = 0;
-      next_set           = 0;
-      mode_new           = 2'b00;
-      mode_we            = 0;
-      work_factor_new    = 0;
-      work_factor_we     = 0;
-      work_factor_num_we = 0;
-      block0_we          = 0;
-      block1_we          = 0;
-      block2_we          = 0;
-      block3_we          = 0;
-      block4_we          = 0;
-      block5_we          = 0;
-      block6_we          = 0;
-      block7_we          = 0;
-      block8_we          = 0;
-      block9_we          = 0;
-      block10_we         = 0;
-      block11_we         = 0;
-      block12_we         = 0;
-      block13_we         = 0;
-      block14_we         = 0;
-      block15_we         = 0;
-      block16_we         = 0;
-      block17_we         = 0;
-      block18_we         = 0;
-      block19_we         = 0;
-      block20_we         = 0;
-      block21_we         = 0;
-      block22_we         = 0;
-      block23_we         = 0;
-      block24_we         = 0;
-      block25_we         = 0;
-      block26_we         = 0;
-      block27_we         = 0;
-      block28_we         = 0;
-      block29_we         = 0;
-      block30_we         = 0;
-      block31_we         = 0;
-      state00_we         = 0;
-      state01_we         = 0;
-      state02_we         = 0;
-      state03_we         = 0;
-      state04_we         = 0;
-      state05_we         = 0;
-      state06_we         = 0;
-      state07_we         = 0;
-      state08_we         = 0;
-      state09_we         = 0;
-      state10_we         = 0;
-      state11_we         = 0;
-      state12_we         = 0;
-      state13_we         = 0;
-      state14_we         = 0;
-      state15_we         = 0;
+      init_new           = 1'h0;
+      next_new           = 1'h0;
+      mode_new           = MODE_SHA_512;
+      mode_we            = 1'h0;
+      work_factor_new    = 1'h0;
+      work_factor_we     = 1'h0;
+      work_factor_num_we = 1'h0;
+      block_we           = 1'h0;
+      state00_we         = 1'h0;
+      state01_we         = 1'h0;
+      state02_we         = 1'h0;
+      state03_we         = 1'h0;
+      state04_we         = 1'h0;
+      state05_we         = 1'h0;
+      state06_we         = 1'h0;
+      state07_we         = 1'h0;
+      state08_we         = 1'h0;
+      state09_we         = 1'h0;
+      state10_we         = 1'h0;
+      state11_we         = 1'h0;
+      state12_we         = 1'h0;
+      state13_we         = 1'h0;
+      state14_we         = 1'h0;
+      state15_we         = 1'h0;
       tmp_read_data      = 32'h00000000;
-      tmp_error          = 0;
+      tmp_error          = 1'h0;
+
+      block_addr = address[4 : 0] - ADDR_BLOCK0[4 : 0];
 
       if (cs)
         begin
           if (we)
             begin
+              if ((address >= ADDR_BLOCK0) && (address <= ADDR_BLOCK31))
+                block_we = 1'h1;
+
               case (address)
-                // Write operations.
                 ADDR_CTRL:
                   begin
-                    init_set        = write_data[CTRL_INIT_BIT];
-                    next_set        = write_data[CTRL_NEXT_BIT];
+                    init_new        = write_data[CTRL_INIT_BIT];
+                    next_new        = write_data[CTRL_NEXT_BIT];
                     mode_new        = write_data[CTRL_MODE_HIGH_BIT : CTRL_MODE_LOW_BIT];
+                    mode_we         = 1'h1;
                     work_factor_new = write_data[CTRL_WORK_FACTOR_BIT];
-                    work_factor_we  = 1;
-                    mode_we         = 1;
+                    work_factor_we  = 1'h1;
                   end
 
                 ADDR_WORK_FACTOR_NUM:
@@ -704,166 +337,6 @@ module sha512(
                     work_factor_num_we = 1;
                   end
 
-                ADDR_BLOCK0:
-                  begin
-                    block0_we = 1;
-                   end
-
-                ADDR_BLOCK1:
-                  begin
-                    block1_we = 1;
-                  end
-
-                ADDR_BLOCK2:
-                  begin
-                    block2_we = 1;
-                  end
-
-                ADDR_BLOCK3:
-                  begin
-                    block3_we = 1;
-                  end
-
-                ADDR_BLOCK4:
-                  begin
-                    block4_we = 1;
-                  end
-
-                ADDR_BLOCK5:
-                  begin
-                    block5_we = 1;
-                  end
-
-                ADDR_BLOCK6:
-                  begin
-                    block6_we = 1;
-                  end
-
-                ADDR_BLOCK7:
-                  begin
-                    block7_we = 1;
-                  end
-
-                ADDR_BLOCK8:
-                  begin
-                    block8_we = 1;
-                  end
-
-                ADDR_BLOCK9:
-                  begin
-                    block9_we = 1;
-                  end
-
-                ADDR_BLOCK10:
-                  begin
-                    block10_we = 1;
-                  end
-
-                ADDR_BLOCK11:
-                  begin
-                    block11_we = 1;
-                  end
-
-                ADDR_BLOCK12:
-                  begin
-                    block12_we = 1;
-                  end
-
-                ADDR_BLOCK13:
-                  begin
-                    block13_we = 1;
-                  end
-
-                ADDR_BLOCK14:
-                  begin
-                    block14_we = 1;
-                  end
-
-                ADDR_BLOCK15:
-                  begin
-                    block15_we = 1;
-                  end
-
-                ADDR_BLOCK16:
-                  begin
-                    block16_we = 1;
-                  end
-
-                ADDR_BLOCK17:
-                  begin
-                    block17_we = 1;
-                  end
-
-                ADDR_BLOCK18:
-                  begin
-                    block18_we = 1;
-                  end
-
-                ADDR_BLOCK19:
-                  begin
-                    block19_we = 1;
-                  end
-
-                ADDR_BLOCK20:
-                  begin
-                    block20_we = 1;
-                  end
-
-                ADDR_BLOCK21:
-                  begin
-                    block21_we = 1;
-                  end
-
-                ADDR_BLOCK22:
-                  begin
-                    block22_we = 1;
-                  end
-
-                ADDR_BLOCK23:
-                  begin
-                    block23_we = 1;
-                  end
-
-                ADDR_BLOCK24:
-                  begin
-                    block24_we = 1;
-                  end
-
-                ADDR_BLOCK25:
-                  begin
-                    block25_we = 1;
-                  end
-
-                ADDR_BLOCK26:
-                  begin
-                    block26_we = 1;
-                  end
-
-                ADDR_BLOCK27:
-                  begin
-                    block27_we = 1;
-                  end
-
-                ADDR_BLOCK28:
-                  begin
-                    block28_we = 1;
-                  end
-
-                ADDR_BLOCK29:
-                  begin
-                    block29_we = 1;
-                  end
-
-                ADDR_BLOCK30:
-                  begin
-                    block30_we = 1;
-                  end
-
-                ADDR_BLOCK31:
-                  begin
-                    block31_we = 1;
-                  end
-
                 ADDR_DIGEST0:
                   state00_we = 1;
 
@@ -921,278 +394,30 @@ module sha512(
 
           else
             begin
+              if ((address >= ADDR_DIGEST0) && (address <= ADDR_DIGEST15))
+                tmp_read_data = digest_reg[(15 - (address - ADDR_DIGEST0)) * 32 +: 32];
+
+              if ((address >= ADDR_BLOCK0) && (address <= ADDR_BLOCK31))
+                tmp_read_data = block_reg[address[4 : 0]];
+
               case (address)
-                // Read operations.
                 ADDR_NAME0:
-                  begin
-                    tmp_read_data = CORE_NAME0;
-                  end
+                  tmp_read_data = CORE_NAME0;
 
                 ADDR_NAME1:
-                  begin
-                    tmp_read_data = CORE_NAME1;
-                  end
+                  tmp_read_data = CORE_NAME1;
 
                 ADDR_VERSION:
-                  begin
-                    tmp_read_data = CORE_VERSION;
-                  end
+                  tmp_read_data = CORE_VERSION;
 
                 ADDR_CTRL:
-                  begin
-                    tmp_read_data = {24'h000000, work_factor_reg, 3'b000,
-                                     mode_reg, next_reg, init_reg};
-                  end
+                  tmp_read_data = {24'h000000, work_factor_reg, 3'b000, mode_reg, next_reg, init_reg};
 
                 ADDR_STATUS:
-                  begin
-                    tmp_read_data = {28'h0000000, 2'b00, digest_valid_reg, ready_reg};
-                  end
+                  tmp_read_data = {28'h0000000, 2'b00, digest_valid_reg, ready_reg};
 
                 ADDR_WORK_FACTOR_NUM:
-                  begin
-                    tmp_read_data = work_factor_num_reg;
-                  end
-
-                ADDR_BLOCK0:
-                  begin
-                    tmp_read_data = block0_reg;
-                  end
-
-                ADDR_BLOCK1:
-                  begin
-                    tmp_read_data = block1_reg;
-                  end
-
-                ADDR_BLOCK2:
-                  begin
-                    tmp_read_data = block2_reg;
-                  end
-
-                ADDR_BLOCK3:
-                  begin
-                    tmp_read_data = block3_reg;
-                  end
-
-                ADDR_BLOCK4:
-                  begin
-                    tmp_read_data = block4_reg;
-                  end
-
-                ADDR_BLOCK5:
-                  begin
-                    tmp_read_data = block5_reg;
-                  end
-
-                ADDR_BLOCK6:
-                  begin
-                    tmp_read_data = block6_reg;
-                  end
-
-                ADDR_BLOCK7:
-                  begin
-                    tmp_read_data = block7_reg;
-                  end
-
-                ADDR_BLOCK8:
-                  begin
-                    tmp_read_data = block8_reg;
-                  end
-
-                ADDR_BLOCK9:
-                  begin
-                    tmp_read_data = block9_reg;
-                  end
-
-                ADDR_BLOCK10:
-                  begin
-                    tmp_read_data = block10_reg;
-                  end
-
-                ADDR_BLOCK11:
-                  begin
-                    tmp_read_data = block11_reg;
-                  end
-
-                ADDR_BLOCK12:
-                  begin
-                    tmp_read_data = block12_reg;
-                  end
-
-                ADDR_BLOCK13:
-                  begin
-                    tmp_read_data = block13_reg;
-                  end
-
-                ADDR_BLOCK14:
-                  begin
-                    tmp_read_data = block14_reg;
-                  end
-
-                ADDR_BLOCK15:
-                  begin
-                    tmp_read_data = block15_reg;
-                  end
-
-                ADDR_BLOCK16:
-                  begin
-                    tmp_read_data = block16_reg;
-                  end
-
-                ADDR_BLOCK17:
-                  begin
-                    tmp_read_data = block17_reg;
-                  end
-
-                ADDR_BLOCK18:
-                  begin
-                    tmp_read_data = block18_reg;
-                  end
-
-                ADDR_BLOCK19:
-                  begin
-                    tmp_read_data = block19_reg;
-                  end
-
-                ADDR_BLOCK20:
-                  begin
-                    tmp_read_data = block20_reg;
-                  end
-
-                ADDR_BLOCK21:
-                  begin
-                    tmp_read_data = block21_reg;
-                  end
-
-                ADDR_BLOCK22:
-                  begin
-                    tmp_read_data = block22_reg;
-                  end
-
-                ADDR_BLOCK23:
-                  begin
-                    tmp_read_data = block23_reg;
-                  end
-
-                ADDR_BLOCK24:
-                  begin
-                    tmp_read_data = block24_reg;
-                  end
-
-                ADDR_BLOCK25:
-                  begin
-                    tmp_read_data = block25_reg;
-                  end
-
-                ADDR_BLOCK26:
-                  begin
-                    tmp_read_data = block26_reg;
-                  end
-
-                ADDR_BLOCK27:
-                  begin
-                    tmp_read_data = block27_reg;
-                  end
-
-                ADDR_BLOCK28:
-                  begin
-                    tmp_read_data = block28_reg;
-                  end
-
-                ADDR_BLOCK29:
-                  begin
-                    tmp_read_data = block29_reg;
-                  end
-
-                ADDR_BLOCK30:
-                  begin
-                    tmp_read_data = block30_reg;
-                  end
-
-                ADDR_BLOCK31:
-                  begin
-                    tmp_read_data = block31_reg;
-                  end
-
-                ADDR_DIGEST0:
-                  begin
-                    tmp_read_data = digest_reg[511 : 480];
-                  end
-
-                ADDR_DIGEST1:
-                  begin
-                    tmp_read_data = digest_reg[479 : 448];
-                  end
-
-                ADDR_DIGEST2:
-                  begin
-                    tmp_read_data = digest_reg[447 : 416];
-                  end
-
-                ADDR_DIGEST3:
-                  begin
-                    tmp_read_data = digest_reg[415 : 384];
-                  end
-
-                ADDR_DIGEST4:
-                  begin
-                    tmp_read_data = digest_reg[383 : 352];
-                  end
-
-                ADDR_DIGEST5:
-                  begin
-                    tmp_read_data = digest_reg[351 : 320];
-                  end
-
-                ADDR_DIGEST6:
-                  begin
-                    tmp_read_data = digest_reg[319 : 288];
-                  end
-
-                ADDR_DIGEST7:
-                  begin
-                    tmp_read_data = digest_reg[287 : 256];
-                  end
-
-                ADDR_DIGEST8:
-                  begin
-                    tmp_read_data = digest_reg[255 : 224];
-                  end
-
-                ADDR_DIGEST9:
-                  begin
-                    tmp_read_data = digest_reg[223 : 192];
-                  end
-
-                ADDR_DIGEST10:
-                  begin
-                    tmp_read_data = digest_reg[191 : 160];
-                  end
-
-                ADDR_DIGEST11:
-                  begin
-                    tmp_read_data = digest_reg[159 : 128];
-                  end
-
-                ADDR_DIGEST12:
-                  begin
-                    tmp_read_data = digest_reg[127 :  96];
-                  end
-
-                ADDR_DIGEST13:
-                  begin
-                    tmp_read_data = digest_reg[95  :  64];
-                  end
-
-                ADDR_DIGEST14:
-                  begin
-                    tmp_read_data = digest_reg[63  :  32];
-                  end
-
-                ADDR_DIGEST15:
-                  begin
-                    tmp_read_data = digest_reg[31  :   0];
-                  end
+                  tmp_read_data = work_factor_num_reg;
 
                 default:
                   begin
diff --git a/src/tb/tb_sha512.v b/src/tb/tb_sha512.v
index 8bc0068..72a50ae 100644
--- a/src/tb/tb_sha512.v
+++ b/src/tb/tb_sha512.v
@@ -218,25 +218,28 @@ module tb_sha512();
 
       $display("Message block:");
       $display("block0  = 0x%08x, block1  = 0x%08x, block2  = 0x%08x,  block3  = 0x%08x",
-               dut.block0_reg, dut.block1_reg, dut.block2_reg, dut.block3_reg);
+               dut.block_reg[0], dut.block_reg[1], dut.block_reg[2], dut.block_reg[3]);
+
       $display("block4  = 0x%08x, block5  = 0x%08x, block6  = 0x%08x,  block7  = 0x%08x",
-               dut.block4_reg, dut.block5_reg, dut.block6_reg, dut.block7_reg);
+               dut.block_reg[4], dut.block_reg[5], dut.block_reg[6], dut.block_reg[7]);
 
       $display("block8  = 0x%08x, block9  = 0x%08x, block10 = 0x%08x,  block11 = 0x%08x",
-               dut.block8_reg, dut.block9_reg, dut.block10_reg, dut.block11_reg);
+               dut.block_reg[8], dut.block_reg[9], dut.block_reg[10], dut.block_reg[11]);
+
       $display("block12 = 0x%08x, block13 = 0x%08x, block14 = 0x%08x,  block15 = 0x%08x",
-               dut.block12_reg, dut.block13_reg, dut.block14_reg, dut.block15_reg);
+               dut.block_reg[12], dut.block_reg[13], dut.block_reg[14], dut.block_reg[15]);
 
       $display("block16 = 0x%08x, block17 = 0x%08x, block18 = 0x%08x,  block19 = 0x%08x",
-               dut.block16_reg, dut.block17_reg, dut.block18_reg, dut.block19_reg);
+               dut.block_reg[16], dut.block_reg[17], dut.block_reg[18], dut.block_reg[19]);
+
       $display("block20 = 0x%08x, block21 = 0x%08x, block22 = 0x%08x,  block23 = 0x%08x",
-               dut.block20_reg, dut.block21_reg, dut.block22_reg, dut.block23_reg);
+               dut.block_reg[20], dut.block_reg[21], dut.block_reg[22], dut.block_reg[23]);
 
       $display("block24 = 0x%08x, block25 = 0x%08x, block26 = 0x%08x,  block27 = 0x%08x",
-               dut.block24_reg, dut.block25_reg, dut.block26_reg, dut.block27_reg);
-      $display("block28 = 0x%08x, block29 = 0x%08x, block30 = 0x%08x,  block31 = 0x%08x",
-               dut.block28_reg, dut.block29_reg, dut.block30_reg, dut.block31_reg);
+               dut.block_reg[24], dut.block_reg[25], dut.block_reg[26], dut.block_reg[27]);
 
+      $display("block28 = 0x%08x, block29 = 0x%08x, block30 = 0x%08x,  block31 = 0x%08x",
+               dut.block_reg[28], dut.block_reg[29], dut.block_reg[30], dut.block_reg[31]);
       $display("");
 
       $display("Digest:");