Adding testbenches for montprod and modexp. The montprod tb has testcases for up to 1024 bit values.

2 files changed, 701 insertions, 0 deletions

diff --git a/src/tb/tb_modexp.v b/src/tb/tb_modexp.v
new file mode 100644
index 0000000..c07d3d5
--- /dev/null
+++ b/src/tb/tb_modexp.v
@@ -0,0 +1,286 @@
+//======================================================================
+//
+// tb_modexp.v
+// -----------
+// Testbench modular exponentiation core.
+//
+//
+// Author: Joachim Strombergson, Peter Magnusson
+// Copyright (c) 2015, NORDUnet A/S All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+// - Redistributions of source code must retain the above copyright notice,
+//   this list of conditions and the following disclaimer.
+//
+// - Redistributions in binary form must reproduce the above copyright
+//   notice, this list of conditions and the following disclaimer in the
+//   documentation and/or other materials provided with the distribution.
+//
+// - Neither the name of the NORDUnet nor the names of its contributors may
+//   be used to endorse or promote products derived from this software
+//   without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+//======================================================================
+
+//------------------------------------------------------------------
+// Simulator directives.
+//------------------------------------------------------------------
+`timescale 1ns/100ps
+
+
+//------------------------------------------------------------------
+// Test module.
+//------------------------------------------------------------------
+module tb_modexp();
+
+  //----------------------------------------------------------------
+  // Internal constant and parameter definitions.
+  //----------------------------------------------------------------
+  parameter DEBUG     = 0;
+
+  localparam CLK_HALF_PERIOD = 1;
+  localparam CLK_PERIOD      = 2 * CLK_HALF_PERIOD;
+
+  // The DUT address map.
+  localparam ADDR_NAME0       = 8'h00;
+  localparam ADDR_NAME1       = 8'h01;
+  localparam ADDR_VERSION     = 8'h02;
+
+  localparam ADDR_CTRL        = 8'h08;
+  localparam CTRL_INIT_BIT    = 0;
+  localparam CTRL_NEXT_BIT    = 1;
+
+
+  //----------------------------------------------------------------
+  // Register and Wire declarations.
+  //----------------------------------------------------------------
+  reg [31 : 0]  cycle_ctr;
+  reg [31 : 0]  error_ctr;
+  reg [31 : 0]  tc_ctr;
+
+  reg [31 : 0]  read_data;
+  reg [127 : 0] result_data;
+
+  reg           tb_clk;
+  reg           tb_reset_n;
+  reg           tb_cs;
+  reg           tb_we;
+  reg [11  : 0]  tb_address;
+  reg [31 : 0]  tb_write_data;
+  wire [31 : 0] tb_read_data;
+  wire          tb_error;
+
+
+  //----------------------------------------------------------------
+  // Device Under Test.
+  //----------------------------------------------------------------
+  modexp dut(
+             .clk(tb_clk),
+             .reset_n(tb_reset_n),
+             .cs(tb_cs),
+             .we(tb_we),
+             .address(tb_address),
+             .write_data(tb_write_data),
+             .read_data(tb_read_data)
+            );
+
+
+  //----------------------------------------------------------------
+  // clk_gen
+  //
+  // Always running clock generator process.
+  //----------------------------------------------------------------
+  always
+    begin : clk_gen
+      #CLK_HALF_PERIOD;
+      tb_clk = !tb_clk;
+    end // clk_gen
+
+
+  //----------------------------------------------------------------
+  // sys_monitor()
+  //
+  // An always running process that creates a cycle counter and
+  // conditionally displays information about the DUT.
+  //----------------------------------------------------------------
+  always
+    begin : sys_monitor
+      cycle_ctr = cycle_ctr + 1;
+
+      #(CLK_PERIOD);
+
+      if (DEBUG)
+        begin
+          dump_dut_state();
+        end
+    end
+
+
+  //----------------------------------------------------------------
+  // dump_dut_state()
+  //
+  // Dump the state of the dump when needed.
+  //----------------------------------------------------------------
+  task dump_dut_state();
+    begin
+      $display("cycle: 0x%016x", cycle_ctr);
+      $display("State of DUT");
+      $display("------------");
+      $display("");
+
+    end
+  endtask // dump_dut_state
+
+
+  //----------------------------------------------------------------
+  // reset_dut()
+  //
+  // Toggle reset to put the DUT into a well known state.
+  //----------------------------------------------------------------
+  task reset_dut();
+    begin
+      $display("*** Toggle reset.");
+      tb_reset_n = 0;
+
+      #(2 * CLK_PERIOD);
+      tb_reset_n = 1;
+      $display("");
+    end
+  endtask // reset_dut
+
+
+  //----------------------------------------------------------------
+  // display_test_results()
+  //
+  // Display the accumulated test results.
+  //----------------------------------------------------------------
+  task display_test_results();
+    begin
+      if (error_ctr == 0)
+        begin
+          $display("*** All %02d test cases completed successfully", tc_ctr);
+        end
+      else
+        begin
+          $display("*** %02d tests completed - %02d test cases did not complete successfully.",
+                   tc_ctr, error_ctr);
+        end
+    end
+  endtask // display_test_results
+
+
+  //----------------------------------------------------------------
+  // init_sim()
+  //
+  // Initialize all counters and testbed functionality as well
+  // as setting the DUT inputs to defined values.
+  //----------------------------------------------------------------
+  task init_sim();
+    begin
+      cycle_ctr          = 0;
+      error_ctr          = 0;
+      tc_ctr             = 0;
+
+      tb_clk             = 0;
+      tb_reset_n         = 1;
+
+      tb_cs              = 0;
+      tb_we              = 0;
+      tb_address         = 8'h00;
+      tb_write_data      = 32'h00000000;
+    end
+  endtask // init_sim
+
+
+  //----------------------------------------------------------------
+  // write_word()
+  //
+  // Write the given word to the DUT using the DUT interface.
+  //----------------------------------------------------------------
+  task write_word(input [11 : 0]  address,
+                  input [31 : 0] word);
+    begin
+      if (DEBUG)
+        begin
+          $display("*** Writing 0x%08x to 0x%02x.", word, address);
+          $display("");
+        end
+
+      tb_address = address;
+      tb_write_data = word;
+      tb_cs = 1;
+      tb_we = 1;
+      #(2 * CLK_PERIOD);
+      tb_cs = 0;
+      tb_we = 0;
+    end
+  endtask // write_word
+
+
+  //----------------------------------------------------------------
+  // read_word()
+  //
+  // Read a data word from the given address in the DUT.
+  // the word read will be available in the global variable
+  // read_data.
+  //----------------------------------------------------------------
+  task read_word(input [11 : 0]  address);
+    begin
+      tb_address = address;
+      tb_cs = 1;
+      tb_we = 0;
+      #(CLK_PERIOD);
+      read_data = tb_read_data;
+      tb_cs = 0;
+
+      if (DEBUG)
+        begin
+          $display("*** Reading 0x%08x from 0x%02x.", read_data, address);
+          $display("");
+        end
+    end
+  endtask // read_word
+
+
+  //----------------------------------------------------------------
+  // main
+  //
+  // The main test functionality.
+  //----------------------------------------------------------------
+  initial
+    begin : main
+
+      $display("   -= Testbench for modexp started =-");
+      $display("    =================================");
+      $display("");
+
+      init_sim();
+      dump_dut_state();
+      reset_dut();
+      dump_dut_state();
+
+      display_test_results();
+
+      $display("");
+      $display("*** modexp simulation done. ***");
+      $finish;
+    end // main
+endmodule // tb_modexp
+
+//======================================================================
+// EOF tb_modexp.v
+//======================================================================
diff --git a/src/tb/tb_montprod.v b/src/tb/tb_montprod.v
new file mode 100644
index 0000000..59ec72e
--- /dev/null
+++ b/src/tb/tb_montprod.v
@@ -0,0 +1,415 @@
+//======================================================================
+//
+// tb_montprod.v
+// -------------
+// Testbench for the montgomery product module.
+//
+//
+// Author: Peter Magnusson, Joachim Strombergson
+// Copyright (c) 2015, NORDUnet A/S All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+// - Redistributions of source code must retain the above copyright notice,
+//   this list of conditions and the following disclaimer.
+//
+// - Redistributions in binary form must reproduce the above copyright
+//   notice, this list of conditions and the following disclaimer in the
+//   documentation and/or other materials provided with the distribution.
+//
+// - Neither the name of the NORDUnet nor the names of its contributors may
+//   be used to endorse or promote products derived from this software
+//   without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+//======================================================================
+
+//------------------------------------------------------------------
+// Simulator directives.
+//------------------------------------------------------------------
+`timescale 1ns/100ps
+
+//------------------------------------------------------------------
+// Test module.
+//------------------------------------------------------------------
+
+module tb_montprod();
+
+//----------------------------------------------------------------
+// Internal constant and parameter definitions.
+//----------------------------------------------------------------
+  parameter SHOW_INIT = 0;
+
+  parameter DUMP_MEM = 0;
+  parameter DEBUG = 0;
+  parameter CLK_HALF_PERIOD = 2;
+  parameter CLK_PERIOD = 2 * CLK_HALF_PERIOD;
+
+
+//----------------------------------------------------------------
+// Register and Wire declarations.
+//----------------------------------------------------------------
+
+reg           tb_clk;
+reg           tb_reset_n;
+reg           tb_calculate;
+wire          tb_ready;
+reg  [ 7 : 0] tb_length;
+wire [ 7 : 0] tb_opa_addr;
+reg  [31 : 0] tb_opa_data;
+wire [ 7 : 0] tb_opb_addr;
+reg  [31 : 0] tb_opb_data;
+wire [ 7 : 0] tb_opm_addr;
+reg  [31 : 0] tb_opm_data;
+wire [ 7 : 0] tb_result_addr;
+wire [31 : 0] tb_result_data;
+wire          tb_result_we;
+
+reg [31 : 0] tb_a [0 : 255]; //tb_opa_data
+reg [31 : 0] tb_b [0 : 255]; //tb_opb_data reads here
+reg [31 : 0] tb_m [0 : 255]; //tb_opm_data reads here
+reg [31 : 0] tb_r [0 : 255]; //tb_result_data writes here
+
+  reg monitor_s;
+
+integer test_mont_prod_success;
+integer test_mont_prod_fail;
+
+//----------------------------------------------------------------
+// Device Under Test.
+//----------------------------------------------------------------
+
+montprod dut(
+ .clk(tb_clk),
+ .reset_n(tb_reset_n),
+ .length(tb_length),
+ .calculate(tb_calculate),
+ .ready(tb_ready),
+ .opa_addr(tb_opa_addr),
+ .opa_data(tb_opa_data),
+ .opb_addr(tb_opb_addr),
+ .opb_data(tb_opb_data),
+ .opm_addr(tb_opm_addr),
+ .opm_data(tb_opm_data),
+ .result_addr(tb_result_addr),
+ .result_data(tb_result_data),
+ .result_we(tb_result_we)
+);
+
+always @(posedge tb_clk)
+  begin : read_test_memory
+    tb_opa_data <= tb_a[tb_opa_addr];
+    tb_opb_data <= tb_b[tb_opb_addr];
+    tb_opm_data <= tb_m[tb_opm_addr];
+
+    if (DUMP_MEM)
+      $display("a %x %x b %x %x m %x %x", tb_opa_addr, tb_a[tb_opa_addr], tb_opb_addr, tb_b[tb_opb_addr], tb_opm_addr, tb_m[tb_opm_addr]);
+  end
+
+always @*
+  begin : write_test_memory
+    if (tb_result_we == 1'b1)
+      begin
+        $display("write %d: %x", tb_result_addr, tb_result_data);
+        tb_r[tb_result_addr] = tb_result_data;
+      end
+  end
+
+
+//----------------------------------------------------------------
+// clk_gen
+//
+// Clock generator process.
+//----------------------------------------------------------------
+always
+  begin : clk_gen
+    #CLK_HALF_PERIOD tb_clk = !tb_clk;
+  end // clk_gen
+
+
+//----------------------------------------------------------------
+// S monitor
+//----------------------------------------------------------------
+  always @ (posedge tb_clk)
+    begin : s_monitor
+      if (monitor_s)
+        $display("S[ 0 ]: %x", dut.s_mem.mem[0] );
+    end
+
+
+
+//----------------------------------------------------------------
+// S monitor
+//----------------------------------------------------------------
+  always @ (posedge tb_clk)
+    begin : s_write_minitor
+      if (monitor_s)
+        if (dut.s_mem_we)
+          $display("Write to S[0x%02x]: 0x%08x", dut.s_mem_wr_addr, dut.s_mem_new);
+    end
+
+
+
+//----------------------------------------------------------------
+//----------------------------------------------------------------
+  always @ (posedge tb_clk)
+    begin : bq_debug
+      if (dut.montprod_ctrl_reg == dut.CTRL_L_CALC_SM)
+        $display("====================> B: %x Q: %x B_bit_index_reg: %x <=====================", dut.b_reg, dut.q_reg, dut.B_bit_index_reg);
+    end
+
+      //case (montprod_ctrl_reg)
+      //  CTRL_LOOP_BQ:
+      //     $display("DEBUG: b: %d q: %d opa_data %x opb_data %x s_mem_read_data %x", b, q, opa_addr_reg, opa_data, opb_data, s_mem_read_data);
+      //  default:
+      //    begin end
+      //endcase
+
+//----------------------------------------------------------------
+//----------------------------------------------------------------
+  always @ (posedge tb_clk)
+    begin : fsm_debug
+      if (dut.montprod_ctrl_we)
+        case (dut.montprod_ctrl_new)
+          dut.CTRL_IDLE:
+            $display("FSM: IDLE");
+          dut.CTRL_INIT_S:
+            $display("FSM: INIT_S");
+          dut.CTRL_LOOP_INIT:
+            $display("FSM: LOOP_INIT");
+          dut.CTRL_LOOP_ITER:
+            $display("FSM: LOOP_ITER");
+          dut.CTRL_LOOP_BQ:
+            $display("FSM: LOOP_BQ");
+          dut.CTRL_L_CALC_SM:
+            $display("FSM: LOOP_CALC_SM");
+          dut.CTRL_L_CALC_SA:
+            $display("FSM: LOOP_CALC_SA");
+          dut.CTRL_L_STALLPIPE_SA:
+            $display("FSM: STALL_PIPE");
+          dut.CTRL_L_CALC_SDIV2:
+            $display("FSM: LOOP_CALC_SDIV2");
+          dut.CTRL_EMIT_S:
+            $display("FSM: LOOP_EMIT_S");
+          dut.CTRL_DONE:
+            $display("FSM: DONE");
+          default:
+            $display("FSM: %x", dut.montprod_ctrl_new);
+        endcase
+    end
+
+
+//----------------------------------------------------------------
+// reset_dut()
+//
+// Toggles reset to force the DUT into a well defined state.
+//----------------------------------------------------------------
+task reset_dut();
+  begin
+    $display("*** Toggle reset.");
+    tb_reset_n = 0;
+    #(4 * CLK_HALF_PERIOD);
+    tb_reset_n = 1;
+  end
+endtask // reset_dut
+
+//----------------------------------------------------------------
+// init_sim()
+//
+// Initialize all counters and testbed functionality as well
+// as setting the DUT inputs to defined values.
+//----------------------------------------------------------------
+task init_sim();
+  begin
+    $display("*** init_sim");
+    tb_clk        = 0;
+    tb_reset_n    = 0;
+    tb_length     = 0;
+    tb_calculate  = 0;
+    monitor_s = 1;
+    test_mont_prod_success = 0;
+    test_mont_prod_fail    = 0;
+  end
+endtask // init_dut
+
+//----------------------------------------------------------------
+// wait_ready()
+//
+// Wait for the ready flag in the dut to be set.
+//
+// Note: It is the callers responsibility to call the function
+// when the dut is actively processing and will in fact at some
+// point set the flag.
+//----------------------------------------------------------------
+task wait_ready();
+  begin
+    $display("*** wait_ready");
+    begin: wait_loop
+      integer i;
+      for (i=0; i<1000000; i=i+1)
+        if (tb_ready == 0)
+          #(2 * CLK_HALF_PERIOD);
+    end
+    if (tb_ready == 0)
+       begin
+         $display("*** wait_ready failed, never became ready!");
+         $finish;
+       end
+  end
+endtask // wait_ready
+
+//----------------------------------------------------------------
+//----------------------------------------------------------------
+task signal_calculate();
+  begin
+    $display("*** signal_calculate");
+    tb_calculate = 1;
+    #(2 * CLK_HALF_PERIOD);
+    tb_calculate = 0;
+  end
+endtask // signal_calculate
+
+
+//----------------------------------------------------------------
+// Tests the montgomery multiplications
+//----------------------------------------------------------------
+task test_mont_prod(
+    input [7 : 0]      length,
+    input [0 : 8192-1] a,
+    input [0 : 8192-1] b,
+    input [0 : 8192-1] m,
+    input [0 : 8192-1] expected
+  );
+  begin
+    $display("*** test started");
+    begin: copy_test_vectors
+      integer i;
+      integer j;
+
+      $display("*** Initializing...");
+      for (i=32'h0; i<256; i=i+1)
+        begin
+          j = {i, 5'h0};
+          tb_a[i] = a[j +: 32];
+          tb_b[i] = b[j +: 32];
+          tb_m[i] = m[j +: 32];
+          tb_r[i] = 32'h0;
+          if (SHOW_INIT)
+            $display("*** init %0x: a: %x b: %x m: %x r: %x", i, tb_a[i], tb_b[i], tb_m[i], tb_r[i]);
+        end
+    end
+
+    $display("*** Test vector copied");
+    wait_ready();
+    tb_length = length;
+    signal_calculate();
+    wait_ready();
+    begin: verify_test_vectors
+      integer i;
+      integer j;
+      integer success;
+      integer fail;
+      success = 1;
+      fail = 0;
+      for (i=0; i<length; i=i+1)
+        begin
+          j = i * 32;
+          $display("offset: %02d expected 0x%08x actual 0x%08x", i, expected[j +: 32], tb_r[i]);
+          if (expected[j +: 32] != tb_r[i])
+            begin
+              success = 0;
+              fail = 1;
+            end
+        end
+      test_mont_prod_success = test_mont_prod_success + success;
+      test_mont_prod_fail    = test_mont_prod_fail + fail;
+    end
+
+    $display("*** test stopped");
+  end
+endtask
+
+//----------------------------------------------------------------
+// The main test functionality.
+//----------------------------------------------------------------
+initial
+  begin : montgomery_product_tests
+    $display("   -- Testbench for montprod started --");
+    init_sim();
+    reset_dut();
+
+//* A=  b B= 11 M= 13 A*B= 10 Ar=  9 Br=  7 Ar*Br=  1 A*B= 10
+
+    test_mont_prod( 1, {32'h9, 8160'h0}, {32'h7, 8160'h0}, {32'h13,8160'h0}, {32'h1,8160'h0} );
+
+//* A=  b B= 13 M= 11 A*B=  5 Ar=  b Br=  2 Ar*Br=  5 A*B=  5
+
+    test_mont_prod( 1, {32'hb, 8160'h0}, {32'h2, 8160'h0}, {32'h11,8160'h0}, {32'h5,8160'h0} );
+
+//* A= 11 B=  b M= 13 A*B= 10 Ar=  7 Br=  9 Ar*Br=  1 A*B= 10
+
+    test_mont_prod( 1, {32'h7, 8160'h0}, {32'h9, 8160'h0}, {32'h13,8160'h0}, {32'h1,8160'h0} );
+
+//* A= 11 B= 13 M=  b A*B=  4 Ar=  2 Br=  a Ar*Br=  5 A*B=  4
+
+    test_mont_prod( 1, {32'h2, 8160'h0}, {32'ha, 8160'h0}, {32'h0b,8160'h0}, {32'h5,8160'h0} );
+
+//* A= 13 B=  b M= 11 A*B=  5 Ar=  2 Br=  b Ar*Br=  5 A*B=  5
+//* A= 13 B= 11 M=  b A*B=  4 Ar=  a Br=  2 Ar*Br=  5 A*B=  4
+//* A=10001 B= 11 M= 13 A*B=  7 Ar= 11 Br=  7 Ar*Br=  4 A*B=  7
+//* A=10001 B= 13 M= 11 A*B=  4 Ar=  2 Br=  2 Ar*Br=  4 A*B=  4
+//* A= 11 B=10001 M= 13 A*B=  7 Ar=  7 Br= 11 Ar*Br=  4 A*B=  7
+//* A= 11 B= 13 M=10001 A*B=143 Ar= 11 Br= 13 Ar*Br=143 A*B=143
+//* A= 13 B=10001 M= 11 A*B=  4 Ar=  2 Br=  2 Ar*Br=  4 A*B=  4
+//* A= 13 B= 11 M=10001 A*B=143 Ar= 13 Br= 11 Ar*Br=143 A*B=143
+//* A=10001 B= 11 M=7fffffff A*B=110011 Ar=20002 Br= 22 Ar*Br=220022 A*B=110011
+//* A=10001 B=7fffffff M= 11 A*B= 10 Ar=  2 Br=  8 Ar*Br= 10 A*B= 10
+//* A= 11 B=10001 M=7fffffff A*B=110011 Ar= 22 Br=20002 Ar*Br=220022 A*B=110011
+//* A= 11 B=7fffffff M=10001 A*B=7ff8 Ar= 11 Br=8000 Ar*Br=7ff8 A*B=7ff8
+//* A=7fffffff B=10001 M= 11 A*B= 10 Ar=  8 Br=  2 Ar*Br= 10 A*B= 10
+//* A=7fffffff B= 11 M=10001 A*B=7ff8 Ar=8000 Br= 11 Ar*Br=7ff8 A*B=7ff8
+
+    //debug A =>        0        0        1
+    //debug B =>        0        0     4000
+    //debug M =>  1ffffff ffffffff ffffffff
+    //debug s =>        0        0       80
+    test_mont_prod( 3, {96'h1, 8096'h0}, {96'h4000, 8096'h0}, {96'h1ffffffffffffffffffffff,8096'h0}, {96'h80,8096'h0} );
+
+ //debug A => 00000000 098b0437 ae647838 09d930b9 a1d269d5 03579a63 9c4e3ac5 fd070836 413389c2 321cfe8b a6a5732e bc7cbcf8 a2f1df87 19f7a767 43ef9b5d 6bd33597 23bfc574 8ec046da 5419d7ff 31811123 740b227b 709f3ace e53ba5cc 38cbc161 a0c15c88 64f26a18 423692ef a5e52a20 80d9f244 717aa2d5 e1a6680a b29eed64 57c6b005
+ //debug B => 00000000 098b0437 ae647838 09d930b9 a1d269d5 03579a63 9c4e3ac5 fd070836 413389c2 321cfe8b a6a5732e bc7cbcf8 a2f1df87 19f7a767 43ef9b5d 6bd33597 23bfc574 8ec046da 5419d7ff 31811123 740b227b 709f3ace e53ba5cc 38cbc161 a0c15c88 64f26a18 423692ef a5e52a20 80d9f244 717aa2d5 e1a6680a b29eed64 57c6b005
+ //debug M => 00000000 f14b5a0a 122ff247 85813db2 02c0d3af bd0a4615 2889ff7d 8f655e9e c866e586 f21003a0 e969769b 127ec8a5 67f07708 217775f7 7654cabc 3a624f9b 4074bdf1 55fa84c0 0354fe59 0ad04cfd 14e666c0 ce6cea72 788c31f4 edcf3dd7 3a5a59c1 b9b3ef41 565df033 69a82de8 f18c2793 0abd5502 f3730ec0 d1943dc4 a660a267
+ //debug s => 00000000 0a8a4a44 40e5c3b0 a05383c2 4ad92fc9 0af7b72e d22fa180 f3a99e64 38ffbe72 3854bc5e 93fffa55 ce49b2cf f809c9eb 81176d8b 4f8b942c 3de18f9c 6393a70a 89924a58 5684cb90 acfd1bde b408b2c0 a8d862c1 74b5a10d 90532d4e 79fe2f50 430decda 0ed75e0a ac354c46 69ce0bd8 eb36e857 b55623d1 527b9711 86cd4d75
+
+    test_mont_prod(
+       33,
+{ 1056'h098b0437ae64783809d930b9a1d269d503579a639c4e3ac5fd070836413389c2321cfe8ba6a5732ebc7cbcf8a2f1df8719f7a76743ef9b5d6bd3359723bfc5748ec046da5419d7ff31811123740b227b709f3acee53ba5cc38cbc161a0c15c8864f26a18423692efa5e52a2080d9f244717aa2d5e1a6680ab29eed6457c6b005
+, 7136'h0 },
+{ 1056'h098b0437ae64783809d930b9a1d269d503579a639c4e3ac5fd070836413389c2321cfe8ba6a5732ebc7cbcf8a2f1df8719f7a76743ef9b5d6bd3359723bfc5748ec046da5419d7ff31811123740b227b709f3acee53ba5cc38cbc161a0c15c8864f26a18423692efa5e52a2080d9f244717aa2d5e1a6680ab29eed6457c6b005
+, 7136'h0 },
+{1056'hf14b5a0a122ff24785813db202c0d3afbd0a46152889ff7d8f655e9ec866e586f21003a0e969769b127ec8a567f07708217775f77654cabc3a624f9b4074bdf155fa84c00354fe590ad04cfd14e666c0ce6cea72788c31f4edcf3dd73a5a59c1b9b3ef41565df03369a82de8f18c27930abd5502f3730ec0d1943dc4a660a267
+, 7136'h0 },
+{1056'h0a8a4a4440e5c3b0a05383c24ad92fc90af7b72ed22fa180f3a99e6438ffbe723854bc5e93fffa55ce49b2cff809c9eb81176d8b4f8b942c3de18f9c6393a70a89924a585684cb90acfd1bdeb408b2c0a8d862c174b5a10d90532d4e79fe2f50430decda0ed75e0aac354c4669ce0bd8eb36e857b55623d1527b971186cd4d75
+, 7136'h0 });
+
+    $display("   -- Testbench for montprod done. --");
+    $display(" tests success: %d", test_mont_prod_success);
+    $display(" tests failed:  %d", test_mont_prod_fail);
+    $finish;
+  end // montprod
+endmodule // tb_montprod
+
+//======================================================================
+// EOF tb_montprod.v
+//======================================================================