Subversion Repositories xge_mac

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

////                                                              ////

////  File name "generic_mem_small.v"                             ////

////                                                              ////

////  This file is part of the "10GE MAC" project                 ////

////  http://www.opencores.org/cores/xge_mac/                     ////

////                                                              ////

////  Author(s):                                                  ////

////      - A. Tanguay (antanguay@opencores.org)                  ////

////                                                              ////

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

////                                                              ////

//// Copyright (C) 2008 AUTHORS. All rights reserved.             ////

////                                                              ////

//// 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; ////

//// either version 2.1 of the License, or (at your option) any   ////

//// later version.                                               ////

////                                                              ////

//// 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.                                                     ////

////                                                              ////

//// You should have received a copy of the GNU Lesser General    ////

//// Public License along with this source; if not, download it   ////

//// from http://www.opencores.org/lgpl.shtml                     ////

////                                                              ////

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

/* synthesis ramstyle = "M512" */

module generic_mem_small(

    wclk,

    wrst_n,

    wen,

    waddr,

    wdata,

    rclk,

    rrst_n,

    ren,

    roen,

    raddr,

    rdata

);

//---

// Parameters

parameter DWIDTH = 32;

parameter AWIDTH = 3;

parameter RAM_DEPTH = (1 << AWIDTH);

parameter REGISTER_READ = 0;

//---

// Ports

input               wclk;

input               wrst_n;

input               wen;

input  [AWIDTH-1:0] waddr;

input  [DWIDTH-1:0] wdata;

input               rclk;

input               rrst_n;

input               ren;

input               roen;

input  [AWIDTH-1:0] raddr;

output [DWIDTH-1:0] rdata;

// Registered outputs

reg    [DWIDTH-1:0] rdata;

//---

// Local declarations

// Registers

reg  [DWIDTH-1:0] mem_rdata;

reg  [AWIDTH-1:0] raddr_d1;

// Memory

reg  [DWIDTH-1:0] mem [0:RAM_DEPTH-1];

// Variables

integer         i;

//---

// Memory Write

// Generate synchronous write

always @(posedge wclk)

begin

    if (wen) begin

        mem[waddr[AWIDTH-1:0]] <= wdata;

    end

end

//---

// Memory Read

// Generate registered memory read

`ifdef XIL

//always @(posedge rclk)

//begin

//    if (ren) begin

//        raddr_d1 <= raddr;

//    end

//end

//always @(raddr_d1, rclk)

//begin

//    mem_rdata = mem[raddr_d1[AWIDTH-1:0]];

//end

always @(posedge rclk)

begin

    if (!rrst_n) begin

        mem_rdata <= {(DWIDTH){1'b0}};

    end else if (ren) begin

        mem_rdata <= mem[raddr[AWIDTH-1:0]];

    end

end

`else

always @(posedge rclk or negedge rrst_n)

begin

    if (!rrst_n) begin

        mem_rdata <= {(DWIDTH){1'b0}};

    end else if (ren) begin

        mem_rdata <= mem[raddr[AWIDTH-1:0]];

    end

end

`endif

generate

    if (REGISTER_READ) begin

        // Generate registered output

        always @(posedge rclk or negedge rrst_n)

        begin

            if (!rrst_n) begin

                rdata <= {(DWIDTH){1'b0}};

            end else if (roen) begin

                rdata <= mem_rdata;

            end

        end

    end

    else begin

        // Generate unregisters output

        always @(mem_rdata)

        begin

            rdata = mem_rdata;

        end

    end

endgenerate

endmodule