Subversion Repositories axi_slave

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

////                                                             ////

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

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

////                                                             ////

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

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

////                                                             ////

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

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

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

////                                                             ////

//// 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.////

////                                                             ////

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

////                                                             ////

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

OUTFILE PREFIX_wresp_fifo.v

INCLUDE def_axi_slave.txt

module PREFIX_wresp_fifo (PORTS);

   parameter                  DEPTH = 8;

   parameter                  DEPTH_BITS =

                              (DEPTH <= 2)   ? 1 :

                              (DEPTH <= 4)   ? 2 :

                              (DEPTH <= 8)   ? 3 :

                              (DEPTH <= 16)  ? 4 :

                              (DEPTH <= 32)  ? 5 :

                              (DEPTH <= 64)  ? 6 :

                              (DEPTH <= 128) ? 7 :

                              (DEPTH <= 256) ? 8 :

                              (DEPTH <= 512) ? 9 : 0; //0 is ilegal

   input                      clk;

   input                      reset;

   input                      AWVALID;

   input                      AWREADY;

   input [ADDR_BITS-1:0]      AWADDR;

   input                      WVALID;

   input                      WREADY;

   input [ID_BITS-1:0]         WID;

   input                      WLAST;

   output [ID_BITS-1:0]       BID;

   output [1:0]        BRESP;

   input                      BVALID;

   input                      BREADY;

   output                     empty;

   output                     pending;

   output                     timeout;

   wire                       timeout_in;

   wire                       timeout_out;

   wire [1:0]                  resp_in;

   reg [ADDR_BITS-1:0]         SLVERR_addr  = {ADDR_BITS{1'b1}};

   reg [ADDR_BITS-1:0]         DECERR_addr  = {ADDR_BITS{1'b1}};

   reg [ADDR_BITS-1:0]         TIMEOUT_addr = {ADDR_BITS{1'b1}};

   wire                       push;

   wire                       push1;

   wire                       pop;

   wire                       empty;

   wire                       full;

   wire [DEPTH_BITS:0]        fullness;

   reg                        pending;

   parameter                  RESP_SLVERR = 2'b10;

   parameter                  RESP_DECERR = 2'b11;

   assign                     resp_in =

                              push1 & (SLVERR_addr == AWADDR) ? RESP_SLVERR :

                              push1 & (DECERR_addr == AWADDR) ? RESP_DECERR : 2'b00;

   assign                     timeout_in = push1 & (TIMEOUT_addr == AWADDR);

   assign                     timeout    = timeout_out & (TIMEOUT_addr != 0);

   always @(posedge clk or posedge reset)

     if (reset)

       pending <= #1 1'b0;

     else if (BVALID & BREADY)

       pending <= #1 1'b0;

     else if (BVALID & (~BREADY))

       pending <= #1 1'b1;

   assign                     push1 = AWVALID & AWREADY;

   assign                     push  = WVALID & WREADY & WLAST;

   assign                     pop   = BVALID & BREADY;

   prgen_fifo_stub #(ID_BITS, DEPTH)

   wresp_fifo(

              .clk(clk),

              .reset(reset),

              .push(push),

              .pop(pop),

              .din({WID

                    }

                   ),

              .dout({BID

                     }

                    ),

              .fullness(fullness),

              .empty(empty),

              .full(full)

              );

   prgen_fifo_stub #(2+1, DEPTH*2)

   wresp_fifo1(

              .clk(clk),

              .reset(reset),

              .push(push1),

              .pop(pop),

              .din({resp_in,

                    timeout_in

                    }

                   ),

              .dout({BRESP,

                     timeout_out

                     }

                    ),

              .fullness(),

              .empty(),

              .full()

              );

endmodule