async_fifo_tb_rd.sv

system verilog fifo env

`include "async_fifo_defines.v"
class async_fifo_tb_rd;
  virtual async_fifo_if async_fifo_inf;

  rand integer rinc_wait;
  rand integer rinc_wait_rand;
  rand integer rinc_wait1;

  FAST_WRD fast_wrd;


  constraint rinc_wait1_c {
                               rinc_wait1 dist {
                                                 0 :/90,
                                                 1 :/10,
                                                 [2:10] :/ 1
                                               };
                          }

  constraint rinc_wait_c {
                            rinc_wait
                                       dist { 
                                              ((fast_wrd==RD) ? (1<<ASIZE)*wrd_ratio : rinc_wait1) :/90,
                                              rinc_wait1 :/ 10
                                              };

                         }

  constraint rinc_wait_rand_c {
                            rinc_wait_rand
                                       dist { 
                                              //((fast_wrd==RD) ? (1<<ASIZE)*wrd_ratio_rand : rinc_wait1) :/90,
                                              rinc_wait1 :/90,
                                              [3:10] :/ 10
                                              };

                         }



  function new ( virtual async_fifo_if async_fifo_inf, FAST_WRD fast_wrd);
      this.async_fifo_inf = async_fifo_inf;
      this.fast_wrd = fast_wrd;
      fork
      begin
         async_fifo_tb_rddata;
      end
      join_none
      async_fifo_inf.rinc  = 1'b0;
  endfunction : new

  task async_fifo_tb_rddata();
       bit randomize_result;
       wait (async_fifo_inf.rrst_n);
`ifdef FIFO_RD_DATA_OPT
              repeat (10) @(posedge async_fifo_inf.rclk);
`endif
       while (1'b1)
       begin
           if (~async_fifo_inf_U.rempty)
           begin
              async_fifo_inf.rinc  = 1'b1;
           end
           else
           begin
              async_fifo_inf.rinc  = 1'b0;
           end
           repeat (1) @(posedge async_fifo_inf.rclk);
           async_fifo_inf.rinc  = 1'b0;
           //repeat ($urandom_range(30,0)) @(posedge async_fifo_inf.rclk);
           randomize_result = this.randomize();
           if (async_fifo_inf_U.wfull)
           begin
              repeat (rinc_wait1) @(posedge async_fifo_inf.rclk);
           end
           else
           begin
              repeat (rinc_wait_rand) @(posedge async_fifo_inf.rclk);
           end
       end
  endtask : async_fifo_tb_rddata

endclass