SV随机约束使用方法---测试例子说明

SV随机约束使⽤⽅法---测试例⼦说明// ********************************************************

// Copyright(c) 2018

// Author : gujiangtao

// File name : random_gen.v

// Module name : random_gen

// Created Time : 2018/8/14 20:25

// Last Modified : ---

// Abstract:

// ========================================================

// Revision Date Author Comment

// -------- --------- --------- ---------

// 1.0 2018/08/14 gujiangtao

//

// ********************************************************

`include "parameter.vh"

class Random_id;

rand bit[9:0] destxr;

rand bit[9:0] destyr;

rand bit[7:0] startr;

rand bit signed [7:0] noiser;

constraint start_N {startr<`per_cyc ;noiser<(`noise_per); noiser>-(`noise_per); }

function new(int seed);

this.srandom(seed);

endfunction

endclass//endclass*/

module random_gen

#(

parameter per_cyc = 10,

parameter x_cord_width_p = "inv",

parameter y_cord_width_p = "inv"

)(

input clk_i,

input reset_i,

input [x_cord_width_p-1:0] my_x_i,

input [y_cord_width_p-1:0] my_y_i,

input out_ready_lo,

output reg destv_en,

output [x_cord_width_p-1:0] dest_x_o,

output [y_cord_width_p-1:0] dest_y_o

);

// tile coordinates

wire [x_cord_width_p-1:0] my_x_i_cast;

wire [y_cord_width_p-1:0] my_y_i_cast;

logic [x_cord_width_p-1:0] dest_x_o_cast;

logic [y_cord_width_p-1:0] dest_y_o_cast;

assign my_x_i_cast = my_x_i;

assign my_y_i_cast = my_y_i;

assign dest_x_o = dest_x_o_cast;

assign dest_y_o = dest_y_o_cast;

logic cp;

int fid;

int random_array[2000-1:0];

int rd, value;

Random_id destxy_random = new(100);

int i, tn;

initial begin

i = 0;

tn = 0;

cp = 0;

rd = 0;

/* fid=$fopen("./random_data.txt","r");

while( rd<1000 ) begin

if(!$fscanf(fid,"%d\n",value))

$display("reading the random_data.txt file is error!");

random_array[rd]= value;

// $display("reading rd=%d ihe random_data%d\n", rd, random_array[rd]);

rd = rd +1;

end

$fclose(fid); */

$readmemh("random_data.txt", random_array);

@(negedge clk_i); // in order to prevent the my_x_i == unkown value x when the initial start

destxy_random.srandom(random_array[my_x_i_cast*my_y_i_cast]);

// $display(">>>random seed (y,x)(%d,%d) \n",my_y_i, my_x_i);

$display(">>>random seed (y,x)(%d,%d) from seed=%d \n",my_y_i, my_x_i, random_array[(my_x_i_cast+1)*(my_y_i_cast+1)]); // destxy_random.randomize();

end

int launch_N;

logic reset_i_r, reset_i_rr;

always_ff @(posedge clk_i)

begin

reset_i_r <= reset_i;

reset_i_rr <= reset_i_r;

end

logic [9:0] destx, desty;

logic [7:0] start;

logic signed [7:0] noise;

always_ff @(posedge clk_i )

begin

// destxy_random.randomize(destxr);

// destxy_random.randomize(destyr);

// destxy_random.randomize(startr);

// destxy_random.randomize(noiser);

destx <= destxy_random.destxr;

desty <= destxy_random.destyr;

start <= destxy_random.startr;

noise <= destxy_random.noiser;

// $display("(x,y,s,n)(%d,%d,%d,%d) \n",destx, desty, start, noise);

end

always @(posedge clk_i)

begin

if(reset_i_rr) begin

launch_N <= noise + `per_cyc;

end

else if(i==launch_N-1 && ~cp && out_ready_lo)

begin

destxy_random.randomize(noiser);

launch_N <= noise + `per_cyc;

end

end

always @(posedge clk_i)

begin

if(reset_i_rr) begin

i <= start%launch_N;

tn <= 0;

end

else begin