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/vhdl/mod_sim_exp_core_tb.vhd File deleted
/vhdl/tb_multiplier_core.vhd
0,0 → 1,684
----------------------------------------------------------------------
---- testbenchtrl ----
---- ----
---- This file is part of the ----
---- Modular Simultaneous Exponentiation Core project ----
---- http://www.opencores.org/cores/mod_sim_exp/ ----
---- ----
---- Description ----
---- testbench for the modular simultaneous exponentiation ----
---- core. Performs some exponentiations to verify the design ----
---- Takes input parameters from sim_input.txt en writes ----
---- result and output to sim_output.txt ----
---- ----
---- Dependencies: ----
---- - multiplier_core ----
---- ----
---- Authors: ----
---- - Geoffrey Ottoy, DraMCo research group ----
---- - Jonas De Craene, JonasDC@opencores.org ----
---- ----
----------------------------------------------------------------------
---- ----
---- Copyright (C) 2011 DraMCo research group and OPENCORES.ORG ----
---- ----
---- This source file may be used and distributed without ----
---- restriction provided that this copyright statement is not ----
---- removed from the file and that any derivative work contains ----
---- the original copyright notice and the associated disclaimer. ----
---- ----
---- This source file is free software; you can redistribute it ----
---- and/or modify it under the terms of the GNU Lesser General ----
---- Public License as published by the Free Software Foundation; ----
---- either version 2.1 of the License, or (at your option) any ----
---- later version. ----
---- ----
---- This source is distributed in the hope that it will be ----
---- useful, but WITHOUT ANY WARRANTY; without even the implied ----
---- warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ----
---- PURPOSE. See the GNU Lesser General Public License for more ----
---- details. ----
---- ----
---- You should have received a copy of the GNU Lesser General ----
---- Public License along with this source; if not, download it ----
---- from http://www.opencores.org/lgpl.shtml ----
---- ----
----------------------------------------------------------------------
 
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
use ieee.std_logic_arith.all;
 
library std;
use std.textio.all;
 
library ieee;
use ieee.std_logic_textio.all;
 
library mod_sim_exp;
use mod_sim_exp.mod_sim_exp_pkg.all;
 
entity tb_multiplier_core is
end tb_multiplier_core;
 
architecture test of tb_multiplier_core is
constant nr_stages : integer := 96;
constant clk_period : time := 10 ns;
signal clk : std_logic := '0';
signal reset : std_logic := '1';
file input : text open read_mode is "src/sim_input.txt";
file output : text open write_mode is "out/sim_output.txt";
------------------------------------------------------------------
-- Signals for multiplier core memory space
------------------------------------------------------------------
signal core_rw_address : std_logic_vector (8 downto 0);
signal core_data_in : std_logic_vector(31 downto 0);
signal core_fifo_din : std_logic_vector(31 downto 0);
signal core_data_out : std_logic_vector(31 downto 0);
signal core_write_enable : std_logic;
signal core_fifo_push : std_logic;
------------------------------------------------------------------
-- Signals for multiplier core control
------------------------------------------------------------------
signal core_start : std_logic;
signal core_run_auto : std_logic;
signal core_p_sel : std_logic_vector(1 downto 0);
signal core_dest_op_single : std_logic_vector(1 downto 0);
signal core_x_sel_single : std_logic_vector(1 downto 0);
signal core_y_sel_single : std_logic_vector(1 downto 0);
signal calc_time : std_logic;
------------------------------------------------------------------
-- Signals for multiplier core interrupt
------------------------------------------------------------------
signal core_fifo_full : std_logic;
signal core_fifo_nopush : std_logic;
signal core_ready : std_logic;
signal core_mem_collision : std_logic;
 
begin
 
------------------------------------------
-- Generate clk
------------------------------------------
clk_process : process
begin
while (true) loop
clk <= '0';
wait for clk_period/2;
clk <= '1';
wait for clk_period/2;
end loop;
end process;
 
------------------------------------------
-- Stimulus Process
------------------------------------------
stim_proc : process
procedure waitclk(n : natural := 1) is
begin
for i in 1 to n loop
wait until rising_edge(clk);
end loop;
end waitclk;
procedure loadOp(constant op_sel : std_logic_vector(2 downto 0);
variable op_data : std_logic_vector(2047 downto 0)) is
begin
wait until rising_edge(clk);
core_rw_address <= op_sel & "000000";
wait until rising_edge(clk);
core_write_enable <= '1';
for i in 0 to (1536/32)-1 loop
assert (core_mem_collision='0')
report "collision detected while writing operand!!" severity failure;
case (core_p_sel) is
when "11" =>
core_data_in <= op_data(((i+1)*32)-1 downto (i*32));
when "01" =>
if (i < 16) then core_data_in <= op_data(((i+1)*32)-1 downto (i*32));
else core_data_in <= x"00000000"; end if;
when "10" =>
if (i >= 16) then core_data_in <= op_data(((i-15)*32)-1 downto ((i-16)*32));
else core_data_in <= x"00000000"; end if;
when others =>
core_data_in <= x"00000000";
end case;
wait until rising_edge(clk);
core_rw_address <= core_rw_address+"000000001";
end loop;
core_write_enable <= '0';
wait until rising_edge(clk);
end loadOp;
procedure readOp(constant op_sel : std_logic_vector(2 downto 0);
variable op_data : out std_logic_vector(2047 downto 0);
variable op_width : integer) is
begin
wait until rising_edge(clk);
core_dest_op_single <= op_sel(1 downto 0);
if (core_p_sel = "10") then
core_rw_address <= op_sel & "010000";
else
core_rw_address <= op_sel & "000000";
end if;
waitclk(2);
for i in 0 to (op_width/32)-2 loop
op_data(((i+1)*32)-1 downto (i*32)) := core_data_out;
core_rw_address <= core_rw_address+"000000001";
waitclk(2);
end loop;
op_data(op_width-1 downto op_width-32) := core_data_out;
wait until rising_edge(clk);
end readOp;
 
function ToString(constant Timeval : time) return string is
variable StrPtr : line;
begin
write(StrPtr,Timeval);
return StrPtr.all;
end ToString;
 
-- variables to read file
variable L : line;
variable Lw : line;
variable base_width : integer;
variable exponent_width : integer;
variable g0 : std_logic_vector(2047 downto 0) := (others=>'0');
variable g1 : std_logic_vector(2047 downto 0) := (others=>'0');
variable e0 : std_logic_vector(2047 downto 0) := (others=>'0');
variable e1 : std_logic_vector(2047 downto 0) := (others=>'0');
variable m : std_logic_vector(2047 downto 0) := (others=>'0');
variable R2 : std_logic_vector(2047 downto 0) := (others=>'0');
variable R : std_logic_vector(2047 downto 0) := (others=>'0');
variable gt0 : std_logic_vector(2047 downto 0) := (others=>'0');
variable gt1 : std_logic_vector(2047 downto 0) := (others=>'0');
variable gt01 : std_logic_vector(2047 downto 0) := (others=>'0');
variable one : std_logic_vector(2047 downto 0) := std_logic_vector(conv_unsigned(1, 2048));
variable result : std_logic_vector(2047 downto 0) := (others=>'0');
variable data_read : std_logic_vector(2047 downto 0) := (others=>'0');
variable good_value : boolean;
variable param_count : integer := 0;
-- constants for operand selection
constant op_modulus : std_logic_vector(2 downto 0) := "100";
constant op_0 : std_logic_vector(2 downto 0) := "000";
constant op_1 : std_logic_vector(2 downto 0) := "001";
constant op_2 : std_logic_vector(2 downto 0) := "010";
constant op_3 : std_logic_vector(2 downto 0) := "011";
variable timer : time;
begin
-- initialisation
-- memory
core_write_enable <= '0';
core_data_in <= x"00000000";
core_rw_address <= "000000000";
-- fifo
core_fifo_din <= x"00000000";
core_fifo_push <= '0';
-- control
core_start <= '0';
core_run_auto <= '0';
core_x_sel_single <= "00";
core_y_sel_single <= "01";
core_dest_op_single <= "01";
core_p_sel <= "11";
-- Generate active high reset signal
reset <= '1';
waitclk(100);
reset <= '0';
waitclk(100);
while not endfile(input) loop
readline(input, L); -- read next line
next when L(1)='-'; -- skip comment lines
-- read input values
case param_count is
when 0 => -- base width
read(L, base_width, good_value);
assert good_value report "Can not read base width" severity failure;
assert false report "Simulating exponentiation" severity note;
write(Lw, string'("----------------------------------------------"));
writeline(output, Lw);
write(Lw, string'("-- EXPONENTIATION --"));
writeline(output, Lw);
write(Lw, string'("----------------------------------------------"));
writeline(output, Lw);
write(Lw, string'("----- Variables used:"));
writeline(output, Lw);
write(Lw, string'("base width: "));
write(Lw, base_width);
writeline(output, Lw);
case (base_width) is
when 1536 => when 1024 => when 512 =>
when others =>
write(Lw, string'("=> incompatible base width!!!")); writeline(output, Lw);
assert false report "incompatible base width!!!" severity failure;
end case;
when 1 => -- exponent width
read(L, exponent_width, good_value);
assert good_value report "Can not read exponent width" severity failure;
write(Lw, string'("exponent width: "));
write(Lw, exponent_width);
writeline(output, Lw);
when 2 => -- g0
hread(L, g0(base_width-1 downto 0), good_value);
assert good_value report "Can not read g0! (wrong lenght?)" severity failure;
write(Lw, string'("g0: "));
hwrite(Lw, g0(base_width-1 downto 0));
writeline(output, Lw);
when 3 => -- g1
hread(L, g1(base_width-1 downto 0), good_value);
assert good_value report "Can not read g1! (wrong lenght?)" severity failure;
write(Lw, string'("g1: "));
hwrite(Lw, g1(base_width-1 downto 0));
writeline(output, Lw);
when 4 => -- e0
hread(L, e0(exponent_width-1 downto 0), good_value);
assert good_value report "Can not read e0! (wrong lenght?)" severity failure;
write(Lw, string'("e0: "));
hwrite(Lw, e0(exponent_width-1 downto 0));
writeline(output, Lw);
when 5 => -- e1
hread(L, e1(exponent_width-1 downto 0), good_value);
assert good_value report "Can not read e1! (wrong lenght?)" severity failure;
write(Lw, string'("e1: "));
hwrite(Lw, e1(exponent_width-1 downto 0));
writeline(output, Lw);
when 6 => -- m
hread(L, m(base_width-1 downto 0), good_value);
assert good_value report "Can not read m! (wrong lenght?)" severity failure;
write(Lw, string'("m: "));
hwrite(Lw, m(base_width-1 downto 0));
writeline(output, Lw);
when 7 => -- R^2
hread(L, R2(base_width-1 downto 0), good_value);
assert good_value report "Can not read R2! (wrong lenght?)" severity failure;
write(Lw, string'("R2: "));
hwrite(Lw, R2(base_width-1 downto 0));
writeline(output, Lw);
when 8 => -- R
hread(L, R(base_width-1 downto 0), good_value);
assert good_value report "Can not read R! (wrong lenght?)" severity failure;
when 9 => -- gt0
hread(L, gt0(base_width-1 downto 0), good_value);
assert good_value report "Can not read gt0! (wrong lenght?)" severity failure;
when 10 => -- gt1
hread(L, gt1(base_width-1 downto 0), good_value);
assert good_value report "Can not read gt1! (wrong lenght?)" severity failure;
when 11 => -- gt01
hread(L, gt01(base_width-1 downto 0), good_value);
assert good_value report "Can not read gt01! (wrong lenght?)" severity failure;
-- select pipeline for all computations
----------------------------------------
writeline(output, Lw);
write(Lw, string'("----- Selecting pipeline: "));
writeline(output, Lw);
case (base_width) is
when 1536 => core_p_sel <= "11"; write(Lw, string'(" Full pipeline selected"));
when 1024 => core_p_sel <= "10"; write(Lw, string'(" Upper pipeline selected"));
when 512 => core_p_sel <= "01"; write(Lw, string'(" Lower pipeline selected"));
when others =>
write(Lw, string'(" Invallid bitwidth for design"));
assert false report "impossible basewidth!" severity failure;
end case;
writeline(output, Lw);
writeline(output, Lw);
write(Lw, string'("----- Writing operands:"));
writeline(output, Lw);
-- load the modulus
--------------------
loadOp(op_modulus, m); -- visual check needed
write(Lw, string'(" m written"));
writeline(output, Lw);
-- load g0
-----------
loadOp(op_0, g0);
-- verify
readOp(op_0, data_read, base_width);
if (g0(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" g0 written in operand_0")); writeline(output, Lw);
else
write(Lw, string'(" failed to write g0 to operand_0!")); writeline(output, Lw);
assert false report "Load g0 to op0 data verify failed!!" severity failure;
end if;
-- load g1
-----------
loadOp(op_1, g1);
-- verify
readOp(op_1, data_read, base_width);
if (g1(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" g1 written in operand_1")); writeline(output, Lw);
else
write(Lw, string'(" failed to write g1 to operand_1!")); writeline(output, Lw);
assert false report "Load g1 to op1 data verify failed!!" severity failure;
end if;
-- load R2
-----------
loadOp(op_2, R2);
-- verify
readOp(op_2, data_read, base_width);
if (R2(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" R^2 written in operand_2")); writeline(output, Lw);
else
write(Lw, string'(" failed to write R^2 to operand_2!")); writeline(output, Lw);
assert false report "Load R2 to op2 data verify failed!!" severity failure;
end if;
-- load a=1
------------
loadOp(op_3, one);
-- verify
readOp(op_3, data_read, base_width);
if (one(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" 1 written in operand_3")); writeline(output, Lw);
else
write(Lw, string'(" failed to write 1 to operand_3!")); writeline(output, Lw);
assert false report "Load 1 to op3 data verify failed!!" severity failure;
end if;
writeline(output, Lw);
write(Lw, string'("----- Pre-computations: "));
writeline(output, Lw);
-- compute gt0
---------------
core_x_sel_single <= "00"; -- g0
core_y_sel_single <= "10"; -- R^2
core_dest_op_single <= "00"; -- op_0 = (g0 * R) mod m
wait until rising_edge(clk);
timer := NOW;
core_start <= '1';
wait until rising_edge(clk);
core_start <= '0';
wait until core_ready = '1';
timer := NOW-timer;
waitclk(10);
readOp(op_0, data_read, base_width);
write(Lw, string'(" Computed gt0: "));
hwrite(Lw, data_read(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" Read gt0: "));
hwrite(Lw, gt0(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" => calc time is "));
write(Lw, string'(ToString(timer)));
writeline(output, Lw);
write(Lw, string'(" => expected time is "));
write(Lw, (nr_stages+(2*(base_width-1)))*clk_period);
writeline(output, Lw);
if (gt0(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" => gt0 is correct!")); writeline(output, Lw);
else
write(Lw, string'(" => Error: gt0 is incorrect!!!")); writeline(output, Lw);
assert false report "gt0 is incorrect!!!" severity failure;
end if;
-- compute gt1
---------------
core_x_sel_single <= "01"; -- g1
core_y_sel_single <= "10"; -- R^2
core_dest_op_single <= "01"; -- op_1 = (g1 * R) mod m
wait until rising_edge(clk);
timer := NOW;
core_start <= '1';
wait until rising_edge(clk);
core_start <= '0';
wait until core_ready = '1';
timer := NOW-timer;
waitclk(10);
readOp(op_1, data_read, base_width);
write(Lw, string'(" Computed gt1: "));
hwrite(Lw, data_read(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" Read gt1: "));
hwrite(Lw, gt1(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" => calc time is "));
write(Lw, string'(ToString(timer)));
writeline(output, Lw);
write(Lw, string'(" => expected time is "));
write(Lw, (nr_stages+(2*(base_width-1)))*clk_period);
writeline(output, Lw);
if (gt1(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" => gt1 is correct!")); writeline(output, Lw);
else
write(Lw, string'(" => Error: gt1 is incorrect!!!")); writeline(output, Lw);
assert false report "gt1 is incorrect!!!" severity failure;
end if;
-- compute a
-------------
core_x_sel_single <= "10"; -- R^2
core_y_sel_single <= "11"; -- 1
core_dest_op_single <= "11"; -- op_3 = (R) mod m
wait until rising_edge(clk);
core_start <= '1';
timer := NOW;
wait until rising_edge(clk);
core_start <= '0';
wait until core_ready = '1';
timer := NOW-timer;
waitclk(10);
readOp(op_3, data_read, base_width);
write(Lw, string'(" Computed a=(R)mod m: "));
hwrite(Lw, data_read(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" Read (R)mod m: "));
hwrite(Lw, R(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" => calc time is "));
write(Lw, string'(ToString(timer)));
writeline(output, Lw);
write(Lw, string'(" => expected time is "));
write(Lw, (nr_stages+(2*(base_width-1)))*clk_period);
writeline(output, Lw);
if (R(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" => (R)mod m is correct!")); writeline(output, Lw);
else
write(Lw, string'(" => Error: (R)mod m is incorrect!!!")); writeline(output, Lw);
assert false report "(R)mod m is incorrect!!!" severity failure;
end if;
-- compute gt01
---------------
core_x_sel_single <= "00"; -- gt0
core_y_sel_single <= "01"; -- gt1
core_dest_op_single <= "10"; -- op_2 = (gt0 * gt1) mod m
wait until rising_edge(clk);
core_start <= '1';
timer := NOW;
wait until rising_edge(clk);
core_start <= '0';
wait until core_ready = '1';
timer := NOW-timer;
waitclk(10);
readOp(op_2, data_read, base_width);
write(Lw, string'(" Computed gt01: "));
hwrite(Lw, data_read(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" Read gt01: "));
hwrite(Lw, gt01(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" => calc time is "));
write(Lw, string'(ToString(timer)));
writeline(output, Lw);
write(Lw, string'(" => expected time is "));
write(Lw, (nr_stages+(2*(base_width-1)))*clk_period);
writeline(output, Lw);
if (gt01(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" => gt01 is correct!")); writeline(output, Lw);
else
write(Lw, string'(" => Error: gt01 is incorrect!!!")); writeline(output, Lw);
assert false report "gt01 is incorrect!!!" severity failure;
end if;
-- load exponent fifo
----------------------
writeline(output, Lw);
write(Lw, string'("----- Loading exponent fifo: "));
writeline(output, Lw);
for i in (exponent_width/16)-1 downto 0 loop
core_fifo_din <= e1((i*16)+15 downto (i*16)) & e0((i*16)+15 downto (i*16));
wait until rising_edge(clk);
core_fifo_push <= '1';
wait until rising_edge(clk);
assert (core_fifo_full='0' and core_fifo_nopush='0')
report "Fifo error, full or nopush" severity failure;
core_fifo_push <= '0';
wait until rising_edge(clk);
end loop;
waitclk(10);
write(Lw, string'(" => Done"));
writeline(output, Lw);
-- start exponentiation
------------------------
writeline(output, Lw);
write(Lw, string'("----- Starting exponentiation: "));
writeline(output, Lw);
core_run_auto <= '1';
wait until rising_edge(clk);
timer := NOW;
core_start <= '1';
wait until rising_edge(clk);
core_start <= '0';
wait until core_ready='1';
timer := NOW-timer;
waitclk(10);
write(Lw, string'(" => calc time is "));
write(Lw, string'(ToString(timer)));
writeline(output, Lw);
write(Lw, string'(" => expected time is "));
write(Lw, ((nr_stages+(2*(base_width-1)))*clk_period*7*exponent_width)/4);
writeline(output, Lw);
write(Lw, string'(" => Done"));
core_run_auto <= '0';
writeline(output, Lw);
-- post-computations
---------------------
writeline(output, Lw);
write(Lw, string'("----- Post-computations: "));
writeline(output, Lw);
-- load in 1 to operand 2
loadOp(op_2, one);
-- verify
readOp(op_2, data_read, base_width);
if (one(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" 1 written in operand_2")); writeline(output, Lw);
else
write(Lw, string'(" failed to write 1 to operand_2!")); writeline(output, Lw);
assert false report "Load 1 to op2 data verify failed!!" severity failure;
end if;
-- compute result
core_x_sel_single <= "11"; -- a
core_y_sel_single <= "10"; -- 1
core_dest_op_single <= "11"; -- op_3 = (a) mod m
wait until rising_edge(clk);
timer := NOW;
core_start <= '1';
wait until rising_edge(clk);
core_start <= '0';
wait until core_ready = '1';
timer := NOW-timer;
waitclk(10);
readOp(op_3, data_read, base_width);
write(Lw, string'(" Computed result: "));
hwrite(Lw, data_read(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" => calc time is "));
write(Lw, string'(ToString(timer)));
writeline(output, Lw);
write(Lw, string'(" => expected time is "));
write(Lw, (nr_stages+(2*(base_width-1)))*clk_period);
writeline(output, Lw);
when 12 => -- check with result
hread(L, result(base_width-1 downto 0), good_value);
assert good_value report "Can not read result! (wrong lenght?)" severity failure;
writeline(output, Lw);
write(Lw, string'("----- verifying result: "));
writeline(output, Lw);
write(Lw, string'(" Read result: "));
hwrite(Lw, result(base_width-1 downto 0));
writeline(output, Lw);
write(Lw, string'(" Computed result: "));
hwrite(Lw, data_read(base_width-1 downto 0));
writeline(output, Lw);
if (result(base_width-1 downto 0) = data_read(base_width-1 downto 0)) then
write(Lw, string'(" => Result is correct!")); writeline(output, Lw);
else
write(Lw, string'(" Error: result is incorrect!!!")); writeline(output, Lw);
assert false report "result is incorrect!!!" severity failure;
end if;
writeline(output, Lw);
 
when others =>
assert false report "undefined state!" severity failure;
end case;
if (param_count = 12) then
param_count := 0;
else
param_count := param_count+1;
end if;
end loop;
wait for 1 us;
assert false report "End of simulation" severity failure;
 
end process;
 
------------------------------------------
-- Multiplier core instance
------------------------------------------
the_multiplier : mod_sim_exp.mod_sim_exp_pkg.multiplier_core
port map(
clk => clk,
reset => reset,
-- operand memory interface (plb shared memory)
write_enable => core_write_enable,
data_in => core_data_in,
rw_address => core_rw_address,
data_out => core_data_out,
collision => core_mem_collision,
-- op_sel fifo interface
fifo_din => core_fifo_din,
fifo_push => core_fifo_push,
fifo_full => core_fifo_full,
fifo_nopush => core_fifo_nopush,
-- ctrl signals
start => core_start,
run_auto => core_run_auto,
ready => core_ready,
x_sel_single => core_x_sel_single,
y_sel_single => core_y_sel_single,
dest_op_single => core_dest_op_single,
p_sel => core_p_sel,
calc_time => calc_time
);
 
end test;

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