Adding functionality to support both SHA224 and SHA256 digest modes. Note: This update changes the ADDR_CTRL API register since it adds a mode bit. The version major number has been bumped to reflect this API change. The top level testbench contains tests for SHA224 as well as old tests for SHA256. The core level tb still only tests SHA256.

1 files changed, 112 insertions, 30 deletions

diff --git a/src/tb/tb_sha256.v b/src/tb/tb_sha256.v
index d881dae..6377688 100644
--- a/src/tb/tb_sha256.v
+++ b/src/tb/tb_sha256.v
@@ -60,6 +60,7 @@ module tb_sha256();
   parameter ADDR_NAME0       = 8'h00;
   parameter ADDR_NAME1       = 8'h01;
   parameter ADDR_VERSION     = 8'h02;
+  parameter CTRL_MODE_VALUE  = 8'h04;
 
   parameter ADDR_CTRL        = 8'h08;
   parameter CTRL_INIT_VALUE  = 8'h01;
@@ -95,6 +96,9 @@ module tb_sha256();
   parameter ADDR_DIGEST6   = 8'h26;
   parameter ADDR_DIGEST7   = 8'h27;
 
+  parameter SHA224_MODE    = 0;
+  parameter SHA256_MODE    = 1;
+
 
   //----------------------------------------------------------------
   // Register and Wire declarations.
@@ -435,17 +439,27 @@ module tb_sha256();
   //
   // Perform test of a single block digest.
   //----------------------------------------------------------------
-  task single_block_test(input [511 : 0] block,
+  task single_block_test(input           mode,
+                         input [511 : 0] block,
                          input [255 : 0] expected);
     begin
       $display("*** TC%01d - Single block test started.", tc_ctr);
 
       write_block(block);
-      write_word(ADDR_CTRL, CTRL_INIT_VALUE);
+
+      if (mode)
+        write_word(ADDR_CTRL, (CTRL_MODE_VALUE + CTRL_INIT_VALUE));
+      else
+        write_word(ADDR_CTRL, CTRL_INIT_VALUE);
+
       #(CLK_PERIOD);
       wait_ready();
       read_digest();
 
+      // We need to ignore the LSW in SHA224 mode.
+      if (mode == SHA224_MODE)
+        digest_data[31 : 0] = 32'h0;
+
       if (digest_data == expected)
         begin
           $display("TC%01d: OK.", tc_ctr);
@@ -470,7 +484,8 @@ module tb_sha256();
   // Perform test of a double block digest. Note that we check
   // the digests for both the first and final block.
   //----------------------------------------------------------------
-  task double_block_test(input [511 : 0] block0,
+  task double_block_test(input           mode,
+                         input [511 : 0] block0,
                          input [255 : 0] expected0,
                          input [511 : 0] block1,
                          input [255 : 0] expected1
@@ -480,11 +495,20 @@ module tb_sha256();
 
       // First block
       write_block(block0);
-      write_word(ADDR_CTRL, CTRL_INIT_VALUE);
+
+      if (mode)
+        write_word(ADDR_CTRL, (CTRL_MODE_VALUE + CTRL_INIT_VALUE));
+      else
+        write_word(ADDR_CTRL, CTRL_INIT_VALUE);
+
       #(CLK_PERIOD);
       wait_ready();
       read_digest();
 
+      // We need to ignore the LSW in SHA224 mode.
+      if (mode == SHA224_MODE)
+        digest_data[31 : 0] = 32'h0;
+
       if (digest_data == expected0)
         begin
           $display("TC%01d first block: OK.", tc_ctr);
@@ -499,11 +523,20 @@ module tb_sha256();
 
       // Final block
       write_block(block1);
-      write_word(ADDR_CTRL, CTRL_NEXT_VALUE);
+
+      if (mode)
+        write_word(ADDR_CTRL, (CTRL_MODE_VALUE + CTRL_NEXT_VALUE));
+      else
+        write_word(ADDR_CTRL, CTRL_NEXT_VALUE);
+
       #(CLK_PERIOD);
       wait_ready();
       read_digest();
 
+      // We need to ignore the LSW in SHA224 mode.
+      if (mode == SHA224_MODE)
+        digest_data[31 : 0] = 32'h0;
+
       if (digest_data == expected1)
         begin
           $display("TC%01d final block: OK.", tc_ctr);
@@ -525,15 +558,19 @@ module tb_sha256();
   //----------------------------------------------------------------
   // restore_state_test()
   //
-  //
   // Perform test of a double block digest. Note that we check
   // the digests for both the first and final block.
   //----------------------------------------------------------------
-  task restore_state_test(input [255 : 0] state,
-                          input [511 : 0] block,
-                          input [255 : 0] expected
-                         );
-    begin
+  task restore_state_test;
+    begin : restore_state
+      reg [255 : 0] state;
+      reg [511 : 0] block;
+      reg [255 : 0] expected;
+
+      state = 256'h85E655D6417A17953363376A624CDE5C76E09589CAC5F811CC4B32C1F20E533A;
+      block = 512'h000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001C0;
+      expected = 256'h248D6A61D20638B8E5C026930C3E6039A33CE45964FF2167F6ECEDD419DB06C1;
+
       $display("*** TC%01d - Restore state test started.", tc_ctr);
 
       // Write state.
@@ -548,7 +585,7 @@ module tb_sha256();
 
       // Process block.
       write_block(block);
-      write_word(ADDR_CTRL, CTRL_NEXT_VALUE);
+      write_word(ADDR_CTRL, (CTRL_MODE_VALUE + CTRL_NEXT_VALUE));
       #(CLK_PERIOD);
       wait_ready();
       read_digest();
@@ -572,14 +609,14 @@ module tb_sha256();
 
 
   //----------------------------------------------------------------
-  // sha256_test
-  // The main test functionality.
+  // sha224_tests()
   //
+  // Run test cases for sha224.
   // Test cases taken from:
-  // http://csrc.nist.gov/groups/ST/toolkit/documents/Examples/SHA256.pdf
+  // http://csrc.nist.gov/groups/ST/toolkit/documents/Examples/SHA224.pdf
   //----------------------------------------------------------------
-  initial
-    begin : sha256_test
+  task sha224_tests;
+    begin : sha224_tests_block
       reg [511 : 0] tc0;
       reg [255 : 0] res0;
 
@@ -588,35 +625,80 @@ module tb_sha256();
       reg [511 : 0] tc1_1;
       reg [255 : 0] res1_1;
 
-      $display("   -- Testbench for sha256 started --");
+      $display("*** Testcases for sha224 functionality started.");
 
-      init_sim();
-      reset_dut();
-      check_name_version();
+      tc0 = 512'h61626380000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000018;
 
-      // dump_dut_state();
-      // write_word(ADDR_BLOCK0, 32'hdeadbeef);
-      // dump_dut_state();
-      // read_word(ADDR_BLOCK0);
-      // dump_dut_state();
+      res0 = 256'h23097D223405D8228642A477BDA255B32AADBCE4BDA0B3F7E36C9DA700000000;
+      single_block_test(SHA224_MODE, tc0, res0);
+
+      tc1_0 = 512'h6162636462636465636465666465666765666768666768696768696A68696A6B696A6B6C6A6B6C6D6B6C6D6E6C6D6E6F6D6E6F706E6F70718000000000000000;
+      res1_0 = 256'h8250e65dbcf62f8466659c3333e5e91a10c8b7b0953927691f1419c200000000;
+      tc1_1 = 512'h000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001C0;
+      res1_1 = 256'h75388b16512776cc5dba5da1fd890150b0c6455cb4f58b195252252500000000;
+      double_block_test(SHA224_MODE, tc1_0, res1_0, tc1_1, res1_1);
+
+      $display("*** Testcases for sha224 functionality completed.");
+    end
+  endtask // sha224_tests
+
+
+  //----------------------------------------------------------------
+  // sha256_tests()
+  //
+  // Run test cases for sha256.
+  // Test cases taken from:
+  // http://csrc.nist.gov/groups/ST/toolkit/documents/Examples/SHA256.pdf
+  //----------------------------------------------------------------
+  task sha256_tests;
+    begin : sha256_tests_block
+      reg [511 : 0] tc0;
+      reg [255 : 0] res0;
+
+      reg [511 : 0] tc1_0;
+      reg [255 : 0] res1_0;
+      reg [511 : 0] tc1_1;
+      reg [255 : 0] res1_1;
+
+      $display("*** Testcases for sha256 functionality started.");
 
       tc0 = 512'h61626380000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000018;
       res0 = 256'hBA7816BF8F01CFEA414140DE5DAE2223B00361A396177A9CB410FF61F20015AD;
-      single_block_test(tc0, res0);
+      single_block_test(SHA256_MODE, tc0, res0);
 
       tc1_0 = 512'h6162636462636465636465666465666765666768666768696768696A68696A6B696A6B6C6A6B6C6D6B6C6D6E6C6D6E6F6D6E6F706E6F70718000000000000000;
       res1_0 = 256'h85E655D6417A17953363376A624CDE5C76E09589CAC5F811CC4B32C1F20E533A;
       tc1_1 = 512'h000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001C0;
       res1_1 = 256'h248D6A61D20638B8E5C026930C3E6039A33CE45964FF2167F6ECEDD419DB06C1;
-      double_block_test(tc1_0, res1_0, tc1_1, res1_1);
+      double_block_test(SHA256_MODE, tc1_0, res1_0, tc1_1, res1_1);
 
-      restore_state_test(res1_0, tc1_1, res1_1);
+      $display("*** Testcases for sha256 functionality completed.");
+    end
+  endtask // sha256_tests
+
+
+  //----------------------------------------------------------------
+  // sha256_top_test
+  // The main test functionality.
+  //----------------------------------------------------------------
+  initial
+    begin : sha256_top_test
+      $display("   -- Testbench for sha256 started --");
+
+      init_sim();
+      reset_dut();
+
+      check_name_version();
+      sha224_tests();
+      sha256_tests();
+      restore_state_test();
 
       display_test_result();
 
       $display("   -- Testbench for sha256 done. --");
       $finish;
-    end // sha256_test
+    end // sha256_top_test
+
 endmodule // tb_sha256
 
 //======================================================================