async_fifo_tb_wr.sv

fifo pointers in verilog gray code utilization for synchronius

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

  rand integer winc_wait;
  rand integer winc_wait_rand;
  rand integer winc_wait1;

  FAST_WRD fast_wrd;

  constraint winc_wait1_c {
                               winc_wait1 dist {
                                                 0 :/90,
                                                 1 :/10,
                                                 [2:10] :/ 1
                                               };
                          }

  constraint winc_wait_c {
                            winc_wait
                                       dist {
                                              ((fast_wrd==WR) ? (1<<ASIZE)*wrd_ratio : winc_wait1) :/90,
                                              winc_wait1 :/ 10
                                              };

                         }

  constraint winc_wait_rand_c {
                            winc_wait_rand
                                       dist {
                                              //((fast_wrd==WR) ? (1<<ASIZE)*wrd_ratio_rand : winc_wait1) :/90,
                                              winc_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;
      $display("WRD_RATIO = %d",wrd_ratio);
      this.fast_wrd = fast_wrd;
      fork
      begin
         async_fifo_tb_wrdata;
      end
      join_none
      async_fifo_inf.winc  = 1'b0;
      async_fifo_inf.wdata = $random;
  endfunction : new

  task async_fifo_tb_wrdata();
       bit randomize_result;
       wait (async_fifo_inf.wrst_n);
`ifdef FIFO_RD_DATA_OPT
              repeat (10) @(posedge async_fifo_inf.rclk);
`endif
       while (1'b1)
       begin
           if (~async_fifo_inf.wfull)
           begin
              async_fifo_inf.winc  = 1'b1;
              async_fifo_inf.wdata = $random;
           end
           else
           begin
              async_fifo_inf.winc  = 1'b0;
           end
           repeat (1) @(posedge async_fifo_inf.wclk);
           async_fifo_inf.winc  = 1'b0;
           //repeat ($urandom_range(20,0)) @(posedge async_fifo_inf.wclk);
           randomize_result = this.randomize();
           if (async_fifo_inf_U.rempty)
           begin
              repeat (winc_wait1) @(posedge async_fifo_inf.wclk);
           end
           else
           begin
              repeat (winc_wait_rand) @(posedge async_fifo_inf.wclk);
           end
       end
  endtask : async_fifo_tb_wrdata

endclass