Subversion Repositories apb_slave

/////////////////////////////////////////////////////////////////////

////                                                             ////

////  Author: Eyal Hochberg                                      ////

////          eyal@provartec.com                                 ////

////                                                             ////

////  Downloaded from: http://www.opencores.org                  ////

/////////////////////////////////////////////////////////////////////

////                                                             ////

//// Copyright (C) 2010 Provartec LTD                            ////

//// www.provartec.com                                           ////

//// info@provartec.com                                          ////

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//// This source file may be used and distributed without        ////

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//// removed from the file and that any derivative work contains ////

//// the original copyright notice and the associated disclaimer.////

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//// 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.////

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//// useful, but WITHOUT ANY WARRANTY; without even the implied  ////

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//// PURPOSE.  See the GNU Lesser General Public License for more////

//// details. http://www.gnu.org/licenses/lgpl.html              ////

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/////////////////////////////////////////////////////////////////////

//////////////////////////////////////

//

// General:

//   The APB slave can use APB or APB3 protocol (APB3 is with pslverr and pready)

//   APB3 is set by DEFINE in def_apb_slave.txt

//   All following tasks regard APB3 only.

//

//

// Tasks:

//

// set_random_delay(input min_delay, input max_delay)

//   Description: Set random wait states on pready

//   Parameters: min_delay - minimum delay

//               max_delay = maximum delay

//

// set_fixed_delay(input delay)

//   Description: Set fixed wait states on pready

//   Parameters: delay - fixed delay on pready

//

// set_slverr(input address)

//   Description: Set address to return slave error (pslverr)

//   Parameters: address - address will return pslverr

// 

// 

//////////////////////////////////////

OUTFILE PREFIX.v

INCLUDE def_apb_slave.txt

module PREFIX(PORTS);

`include "prgen_rand.v"

   parameter                  SLAVE_NUM = 0;

   input                      clk;

   input                      reset;

   revport                    GROUP_STUB_APB;

   wire                       GROUP_STUB_MEM;

IFDEF APB3

  reg                busy_rand_enable = 0; //enable random busy

  integer            busy_min         = 0; //min busy cycles

  integer            busy_max         = 5; //max busy cycles

   integer           busy_delay       = 1; //fixed delay for pready

   reg               err_enable = 0;

   reg [ADDR_BITS-1:0] err_addr = {ADDR_BITS{1'b1}}; //error address

   wire               pslverr   = err_enable && (paddr == err_addr);

   reg                pready = 1'b1;

   always @(negedge clk)

     begin

        #FFD;

        if (psel)

          begin

             if (busy_rand_enable)

               begin

                  busy_delay = rand(busy_min, busy_max);

               end

             if (busy_delay > 0)

               begin

                  pready = 1'b0;

                  repeat (busy_delay)

                    begin

                       @(posedge clk); #FFD;

                    end

                  pready = 1'b1;

                  @(posedge clk); #FFD;

               end

          end

     end

   task set_random_delay;

      input [31:0] delay_min;

      input [31:0] delay_max;

      begin

         busy_rand_enable = 1;

         busy_min = delay_min;

         busy_max = delay_max;

      end

   endtask

   task set_fixed_delay;

      input [31:0] delay;

      begin

         busy_rand_enable = 0;

         busy_delay = delay;

      end

   endtask

   task set_slverr;

      input [31:0] addr;

      begin

         err_enable = 1;

         err_addr = addr;

      end

   endtask

ELSE APB3

   wire  pready  = 1'b1;

   wire  pslverr = 1'b0;

ENDIF APB3

   assign WR      = psel & penable & pwrite;

   assign RD      = psel & (~penable) & (~pwrite);

   assign ADDR_WR = paddr;

   assign ADDR_RD = paddr;

   assign DIN     = pwdata;

   assign BSEL    = 4'b1111;

   assign prdata  = pready ? DOUT : {DATA_BITS{1'bx}};

   CREATE apb_slave_mem.v

   PREFIX_mem PREFIX_mem(

                         .clk(clk),

                         .reset(reset),

                         .GROUP_STUB_MEM(GROUP_STUB_MEM),

                         STOMP ,

                         );

   IFDEF TRACE

     CREATE apb_slave_trace.v

       PREFIX_trace #(SLAVE_NUM)

         PREFIX_trace(

                      .clk(clk),

                      .reset(reset),

                      .GROUP_STUB_MEM(GROUP_STUB_MEM),

                      STOMP ,

                      );

   ENDIF TRACE

endmodule