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[/] [minsoc/] [trunk/] [bench/] [verilog/] [minsoc_memory_model.v] - Blame information for rev 71

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1 2 rfajardo
//////////////////////////////////////////////////////////////////////
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////                                                              ////
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////         Wishbone Single-Port Synchronous RAM                                 ////
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////                    Memory Model                                      ////
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////                                                              ////
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////  This file is part of memory library available from          ////
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////  http://www.opencores.org/cvsweb.shtml/minsoc/                       ////
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////                                                              ////
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////  Description                                                 ////
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////  This Wishbone controller connects to the wrapper of         ////
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////  the single-port synchronous memory interface.               ////
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////  Besides universal memory due to onchip_ram it provides a    ////
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////  generic way to set the depth of the memory.                 ////
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////                                                              ////
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////  To Do:                                                      ////
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////                                                              ////
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////  Author(s):                                                  ////
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////      - Raul Fajardo, rfajardo@gmail.com                      ////
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////                                                              ////
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//////////////////////////////////////////////////////////////////////
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////                                                              ////
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//// Copyright (C) 2000 Authors and OPENCORES.ORG                 ////
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////                                                              ////
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//// This source file may be used and distributed without         ////
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//// restriction provided that this copyright statement is not    ////
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//// removed from the file and that any derivative work contains  ////
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//// the original copyright notice and the associated disclaimer. ////
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////                                                              ////
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//// This source file is free software; you can redistribute it   ////
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//// and/or modify it under the terms of the GNU Lesser General   ////
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//// Public License as published by the Free Software Foundation; ////
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//// either version 2.1 of the License, or (at your option) any   ////
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//// later version.                                               ////
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////                                                              ////
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//// This source is distributed in the hope that it will be       ////
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//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
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//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
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//// PURPOSE.  See the GNU Lesser General Public License for more ////
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//// details.                                                     ////
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////                                                              ////
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//// You should have received a copy of the GNU Lesser General    ////
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//// Public License along with this source; if not, download it   ////
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//// from http://www.gnu.org/licenses/lgpl.html                   ////
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////                                                              ////
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//////////////////////////////////////////////////////////////////////
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//
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// Revision History
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//
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//
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// Revision 1.0 2009/08/18 15:15:00   fajardo
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// Created interface and tested
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//
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54 71 rfajardo
`include "timescale.v"
55 2 rfajardo
 
56 60 rfajardo
module minsoc_memory_model (
57 2 rfajardo
  wb_clk_i, wb_rst_i,
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  wb_dat_i, wb_dat_o, wb_adr_i, wb_sel_i, wb_we_i, wb_cyc_i,
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  wb_stb_i, wb_ack_o, wb_err_o
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);
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// 
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// Parameters 
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//
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parameter    adr_width = 2;
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// 
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// I/O Ports 
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// 
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input      wb_clk_i;
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input      wb_rst_i;
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// 
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// WB slave i/f 
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// 
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input  [31:0]   wb_dat_i;
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output [31:0]   wb_dat_o;
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input  [31:0]   wb_adr_i;
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input  [3:0]    wb_sel_i;
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input      wb_we_i;
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input      wb_cyc_i;
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input      wb_stb_i;
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output     wb_ack_o;
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output     wb_err_o;
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// 
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// Internal regs and wires 
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// 
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wire    we;
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wire [3:0]  be_i;
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wire [31:0]  wb_dat_o;
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reg    ack_we;
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reg    ack_re;
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// 
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// Aliases and simple assignments 
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// 
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assign wb_ack_o = ack_re | ack_we;
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assign wb_err_o = wb_cyc_i & wb_stb_i & (|wb_adr_i[23:adr_width+2]);  // If Access to > (8-bit leading prefix ignored) 
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assign we = wb_cyc_i & wb_stb_i & wb_we_i & (|wb_sel_i[3:0]);
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assign be_i = (wb_cyc_i & wb_stb_i) * wb_sel_i;
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// 
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// Write acknowledge 
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// 
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always @ (negedge wb_clk_i or posedge wb_rst_i)
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begin
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if (wb_rst_i)
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    ack_we <= 1'b0;
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  else
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  if (wb_cyc_i & wb_stb_i & wb_we_i & ~ack_we)
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    ack_we <= #1 1'b1;
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  else
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    ack_we <= #1 1'b0;
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end
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// 
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// read acknowledge 
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// 
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always @ (posedge wb_clk_i or posedge wb_rst_i)
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begin
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  if (wb_rst_i)
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    ack_re <= 1'b0;
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  else
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  if (wb_cyc_i & wb_stb_i & ~wb_err_o & ~wb_we_i & ~ack_re)
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    ack_re <= #1 1'b1;
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  else
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    ack_re <= #1 1'b0;
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end
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    minsoc_onchip_ram #
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        (
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                .aw(adr_width)
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        )
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        block_ram_0 (
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        .clk(wb_clk_i),
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        .rst(wb_rst_i),
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        .addr(wb_adr_i[adr_width+1:2]),
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        .di(wb_dat_i[7:0]),
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        .doq(wb_dat_o[7:0]),
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        .we(we),
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        .oe(1'b1),
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        .ce(be_i[0]));
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    minsoc_onchip_ram #
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        (
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                .aw(adr_width)
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        )
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        block_ram_1 (
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        .clk(wb_clk_i),
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        .rst(wb_rst_i),
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        .addr(wb_adr_i[adr_width+1:2]),
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        .di(wb_dat_i[15:8]),
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        .doq(wb_dat_o[15:8]),
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        .we(we),
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        .oe(1'b1),
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        .ce(be_i[1]));
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    minsoc_onchip_ram #
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        (
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                .aw(adr_width)
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        )
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        block_ram_2 (
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        .clk(wb_clk_i),
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        .rst(wb_rst_i),
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        .addr(wb_adr_i[adr_width+1:2]),
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        .di(wb_dat_i[23:16]),
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        .doq(wb_dat_o[23:16]),
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        .we(we),
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        .oe(1'b1),
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        .ce(be_i[2]));
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    minsoc_onchip_ram #
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        (
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                .aw(adr_width)
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        )
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        block_ram_3 (
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        .clk(wb_clk_i),
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        .rst(wb_rst_i),
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        .addr(wb_adr_i[adr_width+1:2]),
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        .di(wb_dat_i[31:24]),
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        .doq(wb_dat_o[31:24]),
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        .we(we),
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        .oe(1'b1),
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        .ce(be_i[3]));
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endmodule
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