Adding a new task that reads out a given number of random data words from the DUT.

1 files changed, 37 insertions, 16 deletions

diff --git a/src/tb/tb_csprng.v b/src/tb/tb_csprng.v
index b9ec4f9..a1ddfbd 100644
--- a/src/tb/tb_csprng.v
+++ b/src/tb/tb_csprng.v
@@ -50,7 +50,7 @@ module tb_csprng();
   //----------------------------------------------------------------
   // Internal constant and parameter definitions.
   //----------------------------------------------------------------
-  parameter DEBUG = 1;
+  parameter DEBUG = 0;
 
   parameter CLK_HALF_PERIOD = 1;
   parameter CLK_PERIOD      = 2 * CLK_HALF_PERIOD;
@@ -357,6 +357,37 @@ module tb_csprng();
 
 
   //----------------------------------------------------------------
+  // read_rng_data()
+  //
+  // Support task that reads a given number of data words
+  // from the DUT via the API.
+  //----------------------------------------------------------------
+  task read_rng_data(input [31 : 0] num_words);
+    reg [31 : 0] i;
+    begin
+      i = 32'h00000000;
+
+      $display("*** Trying to read 0x%08x RNG data words", num_words);
+      while (i < num_words)
+        begin
+          tb_cs      = 1'b1;
+          tb_we      = 1'b0;
+          tb_address = ADDR_RND_DATA;
+          i = i + 1;
+
+          #CLK_PERIOD;
+
+          if (DEBUG)
+            $display("*** RNG data word 0x%08x: 0x%08x", i, tb_read_data);
+        end
+
+      tb_cs = 1'b0;
+      $display("*** Reading of RNG data words completed.");
+    end
+  endtask // read_rng_data
+
+
+  //----------------------------------------------------------------
   // tc1_init_csprng()
   //
   // TC1: Test that the DUT automatically starts initialize when
@@ -373,11 +404,7 @@ module tb_csprng();
       tb_seed_syn  = 1'b1;
 
       // Start pulling data.
-      tb_cs        = 1'b1;
-      tb_we        = 1'b0;
-      tb_address   = ADDR_RND_DATA;
-
-      #(200 * CLK_PERIOD);
+      read_rng_data(32'h100);
 
       $display("*** TC1: Test automatic init of csprng done.");
     end
@@ -399,16 +426,11 @@ module tb_csprng();
       tb_seed_data = {8{64'h0102030405060708}};
       tb_seed_syn  = 1'b1;
 
-      // Set the max block size to a low value
+      // Set the max number of blocks to a low value
       write_word(ADDR_NUM_BLOCKS_HIGH, 32'h00000000);
-      write_word(ADDR_NUM_BLOCKS_LOW, 32'h00000001);
-
-      // Start pulling data.
-      tb_cs      = 1'b1;
-      tb_we      = 1'b0;
-      tb_address = ADDR_RND_DATA;
+      write_word(ADDR_NUM_BLOCKS_LOW, 32'h00000007);
 
-      #(200 * CLK_PERIOD);
+      read_rng_data(32'h10000);
 
       $display("*** TC2 done..");
     end
@@ -432,8 +454,7 @@ module tb_csprng();
       reset_dut();
       dump_dut_state();
 
-      test_gen_data();
-      tc1_init_csprng();
+//      tc1_init_csprng();
       tc2_reseed_csprng();
 
       display_test_results();