//======================================================================
//
// tb_expoentiator.v
// -----------------------------------------------------------------------------
// Testbench for Montgomery modular exponentiation block.
//
// Authors: Pavel Shatov
//
// Copyright (c) 2017, 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.
//
//======================================================================
`timescale 1ns / 1ps
module tb_exponentiator;
//
// Test Vectors
//
`include "modexp_fpga_model_vectors.v";
//
// Parameters
//
localparam NUM_WORDS_384 = 384 / 32;
localparam NUM_WORDS_512 = 512 / 32;
//
// Clock (100 MHz)
//
reg clk = 1'b0;
always #5 clk = ~clk;
//
// Inputs
//
reg rst_n;
reg ena;
reg [ 3: 0] n_num_words;
reg [ 8: 0] d_num_bits;
//
// Outputs
//
wire rdy;
//
// Integers
//
integer w;
//
// BRAM Interfaces
//
wire [ 3: 0] core_m_addr;
wire [ 3: 0] core_d_addr;
wire [ 3: 0] core_f_addr;
wire [ 3: 0] core_n1_addr;
wire [ 3: 0] core_n2_addr;
wire [ 3: 0] core_n_coeff1_addr;
wire [ 3: 0] core_n_coeff2_addr;
wire [ 3: 0] core_r_addr;
wire [31: 0] core_m_data;
wire [31: 0] core_d_data;
wire [31: 0] core_f_data;
wire [31: 0] core_n1_data;
wire [31: 0] core_n2_data;
wire [31: 0] core_n_coeff1_data;
wire [31: 0] core_n_coeff2_data;
wire [31: 0] core_r_data_in;
wire core_r_wren;
reg [ 3: 0] tb_mdfn_addr;
reg [ 3: 0] tb_r_addr;
reg [31:0] tb_m_data;
reg [31:0] tb_d_data;
reg [31:0] tb_f_data;
reg [31:0] tb_n_data;
reg [31:0] tb_n_coeff_data;
wire [31:0] tb_r_data;
reg tb_mdfn_wren;
//
// BRAMs
//
bram_1rw_1ro_readfirst #(.MEM_WIDTH(32), .MEM_ADDR_BITS(4))
bram_m (.clk(clk),
.a_addr(tb_mdfn_addr), .a_wr(tb_mdfn_wren), .a_in(tb_m_data), .a_out(),
.b_addr(core_m_addr), .b_out(core_m_data));
bram_1rw_1ro_readfirst #(.MEM_WIDTH(32), .MEM_ADDR_BITS(4))
bram_d (.clk(clk),
.a_addr(tb_mdfn_addr), .a_wr(tb_mdfn_wren), .a_in(tb_d_data), .a_out(),
.b_addr(core_d_addr), .b_out(core_d_data));
bram_1rw_1ro_readfirst #(.MEM_WIDTH(32), .MEM_ADDR_BITS(4))
bram_f (.clk(clk),
.a_addr(tb_mdfn_addr), .a_wr(tb_mdfn_wren), .a_in(tb_f_data), .a_out(),
.b_addr(core_f_addr), .b_out(core_f_data));
bram_1rw_1ro_readfirst #(.MEM_WIDTH(32), .MEM_ADDR_BITS(4))
bram_n1 (.clk(clk),
.a_addr(tb_mdfn_addr), .a_wr(tb_mdfn_wren), .a_in(tb_n_data), .a_out(),
.b_addr(core_n1_addr), .b_out(core_n1_data));
bram_1rw_1ro_readfirst #(.MEM_WIDTH(32), .MEM_ADDR_BITS(4))
bram_n2 (.clk(clk),
.a_addr(tb_mdfn_addr), .a_wr(tb_mdfn_wren), .a_in(tb_n_data), .a_out(),
.b_addr(core_n2_addr), .b_out(core_n2_data));
bram_1rw_1ro_readfirst #(.MEM_WIDTH(32), .MEM_ADDR_BITS(4))
bram_n_coeff1 (.clk(clk),
.a_addr(tb_mdfn_addr), .a_wr(tb_mdfn_wren), .a_in(tb_n_coeff_data), .a_out(),
.b_addr(core_n_coeff1_addr), .b_out(core_n_coeff1_data));
bram_1rw_1ro_readfirst #(.MEM_WIDTH(32), .MEM_ADDR_BITS(4))
bram_n_coeff2 (.clk(clk),
.a_addr(tb_mdfn_addr), .a_wr(tb_mdfn_wren), .a_in(tb_n_coeff_data), .a_out(),
.b_addr(core_n_coeff2_addr), .b_out(core_n_coeff2_data));
bram_1rw_1ro_readfirst #(.MEM_WIDTH(32), .MEM_ADDR_BITS(4))
bram_r (.clk(clk),
.a_addr(core_r_addr), .a_wr(core_r_wren), .a_in(core_r_data_in), .a_out(),
.b_addr(tb_r_addr), .b_out(tb_r_data));
//
// UUT
//
modexpa7_exponentiator #
(
.OPERAND_ADDR_WIDTH (4), // 32 * (2**4) = 512-bit operands
.SYSTOLIC_ARRAY_POWER (2) // 2 ** 2 = 4-tap systolic array
)
uut
(
.clk (clk),
.rst_n (rst_n),
.ena (ena),
.rdy (rdy),
.m_bram_addr (core_m_addr),
.d_bram_addr (core_d_addr),
.f_bram_addr (core_f_addr),
.n1_bram_addr (core_n1_addr),
.n2_bram_addr (core_n2_addr),
.n_coeff1_bram_addr (core_n_coeff1_addr),
.n_coeff2_bram_addr (core_n_coeff2_addr),
.r_bram_addr (core_r_addr),
.m_bram_out (core_m_data),
.d_bram_out (core_d_data),
.f_bram_out (core_f_data),
.n1_bram_out (core_n1_data),
.n2_bram_out (core_n2_data),
.n_coeff1_bram_out (core_n_coeff1_data),
.n_coeff2_bram_out (core_n_coeff1_data),
.r_bram_in (core_r_data_in),
.r_bram_wr (core_r_wren),
.m_num_words (n_num_words),
.d_num_bits (d_num_bits)
);
//
// Script
//
initial begin
rst_n = 1'b0;
ena = 1'b0;
#200;
rst_n = 1'b1;
#100;
test_exponent_384(M_384, D_384, FACTOR_384, N_384, N_COEFF_384, S_384);
test_exponent_512(M_512, D_512, FACTOR_512, N_512, N_COEFF_512, S_512);
end
//
// Test Tasks
//
task test_exponent_384;
//
input [383:0] m;
input [383:0] d;
input [383:0] f;
input [383:0] n;
input [383:0] n_coeff;
input [383:0] s;
reg [383:0] r;
//
integer i;
//
begin
//
n_num_words = 4'd11; // set number of words
d_num_bits = 9'd383; // set number of bits
//
write_memory_384(m, d, f, n, n_coeff); // fill memory
ena = 1; // start operation
#10; //
ena = 0; // clear flag
while (!rdy) #10; // wait for operation to complete
read_memory_384(r); // get result from memory
$display(" calculated: %x", r); // display result
$display(" expected: %x", s); //
// check calculated value
if (r === s) begin
$display(" OK");
$display("SUCCESS: Test passed.");
end else begin
$display(" ERROR");
$display("FAILURE: Test not passed.");
end
//
end
//
endtask
task test_exponent_512;
//
input [511:0] m;
input [511:0] d;
input [511:0] f;
input [511:0] n;
input [511:0] n_coeff;
input [511:0] s;
reg [511:0] r;
//
integer i;
//
begin
//
n_num_words = 4'd15; // set number of words
d_num_bits = 9'd511; // set number of bits
//
write_memory_512(m, d, f, n, n_coeff); // fill memory
ena = 1; // start operation
#10; //
ena = 0; // clear flag
while (!rdy) #10; // wait for operation to complete
read_memory_512(r); // get result from memory
$display(" calculated: %x", r); // display result
$display(" expected: %x", s); //
// check calculated value
if (r === s) begin
$display(" OK");
$display("SUCCESS: Test passed.");
end else begin
$display(" ERROR");
$display("FAILURE: Test not passed.");
end
//
end
//
endtask
//
// write_memory_384
//
task write_memory_384;
//
input [383:0] m;
input [383:0] d;
input [383:0] f;
input [383:0] n;
input [383:0] n_coeff;
reg [383:0] m_shreg;
reg [383:0] f_shreg;
reg [383:0] d_shreg;
reg [383:0] n_shreg;
reg [383:0] n_coeff_shreg;
//
begin
//
tb_mdfn_wren = 1; // start filling memories
m_shreg = m; // preload shift register
d_shreg = d; // preload shift register
f_shreg = f; // preload shift register
n_shreg = n; // preload shift register
n_coeff_shreg = n_coeff; // preload shift register
//
for (w=0; w<NUM_WORDS_384; w=w+1) begin // write all words
tb_mdfn_addr = w[3:0]; // set address
tb_m_data = m_shreg[31:0]; // set data
tb_d_data = d_shreg[31:0]; // set data
tb_f_data = f_shreg[31:0]; // set data
tb_n_data = n_shreg[31:0]; // set data
tb_n_coeff_data = n_coeff_shreg[31:0]; // set data
m_shreg = {{32{1'bX}}, m_shreg[383:32]}; // update shift register
d_shreg = {{32{1'bX}}, d_shreg[383:32]}; // update shift register
f_shreg = {{32{1'bX}}, f_shreg[383:32]}; // update shift register
n_shreg = {{32{1'bX}}, n_shreg[383:32]}; // update shift register
n_coeff_shreg = {{32{1'bX}}, n_coeff_shreg[383:32]}; // update shift register
#10; // wait for 1 clock tick
end
//
tb_mdfn_addr = {4{1'bX}}; // wipe addresses
tb_m_data = {32{1'bX}}; // wipe data
tb_d_data = {32{1'bX}}; // wipe data
tb_f_data = {32{1'bX}}; // wipe data
tb_n_data = {32{1'bX}}; // wipe data
tb_n_coeff_data = {32{1'bX}}; // wipe data
tb_mdfn_wren = 0; // stop filling memory
//
end
//
endtask
//
// write_memory_512
//
task write_memory_512;
//
input [511:0] m;
input [511:0] d;
input [511:0] f;
input [511:0] n;
input [511:0] n_coeff;
reg [511:0] m_shreg;
reg [511:0] f_shreg;
reg [511:0] d_shreg;
reg [511:0] n_shreg;
reg [511:0] n_coeff_shreg;
//
begin
//
tb_mdfn_wren = 1; // start filling memories
m_shreg = m; // preload shift register
d_shreg = d; // preload shift register
f_shreg = f; // preload shift register
n_shreg = n; // preload shift register
n_coeff_shreg = n_coeff; // preload shift register
//
for (w=0; w<NUM_WORDS_512; w=w+1) begin // write all words
tb_mdfn_addr = w[3:0]; // set address
tb_m_data = m_shreg[31:0]; // set data
tb_d_data = d_shreg[31:0]; // set data
tb_f_data = f_shreg[31:0]; // set data
tb_n_data = n_shreg[31:0]; // set data
tb_n_coeff_data = n_coeff_shreg[31:0]; // set data
m_shreg = {{32{1'bX}}, m_shreg[511:32]}; // update shift register
d_shreg = {{32{1'bX}}, d_shreg[511:32]}; // update shift register
f_shreg = {{32{1'bX}}, f_shreg[511:32]}; // update shift register
n_shreg = {{32{1'bX}}, n_shreg[511:32]}; // update shift register
n_coeff_shreg = {{32{1'bX}}, n_coeff_shreg[511:32]}; // update shift register
#10; // wait for 1 clock tick
end
//
tb_mdfn_addr = {4{1'bX}}; // wipe addresses
tb_m_data = {32{1'bX}}; // wipe data
tb_d_data = {32{1'bX}}; // wipe data
tb_f_data = {32{1'bX}}; // wipe data
tb_n_data = {32{1'bX}}; // wipe data
tb_n_coeff_data = {32{1'bX}}; // wipe data
tb_mdfn_wren = 0; // stop filling memory
//
end
//
endtask
//
// read_memory_384
//
task read_memory_384;
//
output [383:0] r;
reg [383:0] r_shreg;
//
begin
//
for (w=0; w<NUM_WORDS_384; w=w+1) begin // read result word-by-word
tb_r_addr = w[3:0]; // set address
#10; // wait for 1 clock tick
r_shreg = {tb_r_data, r_shreg[383:32]}; // store data word
end
//
tb_r_addr = {4{1'bX}}; // wipe address
r = r_shreg; // return
//
end
//
endtask
//
// read_memory_512
//
task read_memory_512;
//
output [511:0] r;
reg [511:0] r_shreg;
//
begin
//
for (w=0; w<NUM_WORDS_512; w=w+1) begin // read result word-by-word
tb_r_addr = w[3:0]; // set address
#10; // wait for 1 clock tick
r_shreg = {tb_r_data, r_shreg[511:32]}; // store data word
end
//
tb_r_addr = {4{1'bX}}; // wipe address
r = r_shreg; // return
//
end
//
endtask
endmodule
//======================================================================
// End of file
//======================================================================
