Subversion Repositories ac97

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////  WISHBONE AC 97 Controller                                  ////

////  WISHBONE Interface Module                                  ////

////                                                             ////

////                                                             ////

////  Author: Rudolf Usselmann                                   ////

////          rudi@asics.ws                                      ////

////                                                             ////

////                                                             ////

////  Downloaded from: http://www.opencores.org/cores/ac97_ctrl/ ////

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//// Copyright (C) 2000-2002 Rudolf Usselmann                    ////

////                         www.asics.ws                        ////

////                         rudi@asics.ws                       ////

////                                                             ////

//// 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 SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////

//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////

//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////

//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////

//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////

//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////

//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////

//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////

//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////

//// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////

//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////

//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////

//// POSSIBILITY OF SUCH DAMAGE.                                 ////

////                                                             ////

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

//  CVS Log

//

//  $Id: ac97_wb_if.v,v 1.4 2002-09-19 06:30:56 rudi Exp $

//

//  $Date: 2002-09-19 06:30:56 $

//  $Revision: 1.4 $

//  $Author: rudi $

//  $Locker:  $

//  $State: Exp $

//

// Change History:

//               $Log: not supported by cvs2svn $

//               Revision 1.3  2002/03/05 04:44:05  rudi

//

//               - Fixed the order of the thrash hold bits to match the spec.

//               - Many minor synthesis cleanup items ...

//

//               Revision 1.2  2001/08/10 08:09:42  rudi

//

//               - Removed RTY_O output.

//               - Added Clock and Reset Inputs to documentation.

//               - Changed IO names to be more clear.

//               - Uniquifyed define names to be core specific.

//

//               Revision 1.1  2001/08/03 06:54:50  rudi

//

//

//               - Changed to new directory structure

//

//               Revision 1.1.1.1  2001/05/19 02:29:16  rudi

//               Initial Checkin

//

//

//

//

`include "ac97_defines.v"

module ac97_wb_if(clk, rst,

                wb_data_i, wb_data_o, wb_addr_i, wb_sel_i, wb_we_i, wb_cyc_i,

                wb_stb_i, wb_ack_o, wb_err_o,

                adr, dout, rf_din, i3_din, i4_din, i6_din,

                rf_we, rf_re, o3_we, o4_we, o6_we, o7_we, o8_we, o9_we,

                i3_re, i4_re, i6_re

                );

input           clk,rst;

// WISHBONE Interface

input   [31:0]   wb_data_i;

output  [31:0]   wb_data_o;

input   [31:0]   wb_addr_i;

input   [3:0]    wb_sel_i;

input           wb_we_i;

input           wb_cyc_i;

input           wb_stb_i;

output          wb_ack_o;

output          wb_err_o;

// Internal Interface

output  [3:0]    adr;

output  [31:0]   dout;

input   [31:0]   rf_din, i3_din, i4_din, i6_din;

output          rf_we;

output          rf_re;

output          o3_we, o4_we, o6_we, o7_we, o8_we, o9_we;

output          i3_re, i4_re, i6_re;

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

//

// Local Wires

//

reg     [31:0]   wb_data_o;

reg     [31:0]   dout;

reg             wb_ack_o;

reg             rf_we;

reg             o3_we, o4_we, o6_we, o7_we, o8_we, o9_we;

reg             i3_re, i4_re, i6_re;

reg             we1, we2;

wire            we;

reg             re2, re1;

wire            re;

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

//

// Modules

//

assign adr = wb_addr_i[5:2];

assign wb_err_o = 1'b0;

always @(posedge clk)

        dout <= #1 wb_data_i;

always @(posedge clk)

        case(wb_addr_i[6:2])    // synopsys parallel_case full_case

           5'he: wb_data_o <= #1 i3_din;

           5'hf: wb_data_o <= #1 i4_din;

           5'h10: wb_data_o <= #1 i6_din;

           default: wb_data_o <= #1 rf_din;

        endcase

always @(posedge clk)

        re1 <= #1 !re2 & wb_cyc_i & wb_stb_i & !wb_we_i & `AC97_REG_SEL;

always @(posedge clk)

        re2 <= #1 re & wb_cyc_i & wb_stb_i & !wb_we_i ;

assign re = re1 & !re2 & wb_cyc_i & wb_stb_i & !wb_we_i;

assign rf_re = re & (wb_addr_i[6:2] < 5'h8);

always @(posedge clk)

        we1 <= #1 !we & wb_cyc_i & wb_stb_i & wb_we_i & `AC97_REG_SEL;

always @(posedge clk)

        we2 <= #1 we1 & wb_cyc_i & wb_stb_i & wb_we_i;

assign we = we1 & !we2 & wb_cyc_i & wb_stb_i & wb_we_i;

always @(posedge clk)

        wb_ack_o <= #1 (re | we) & wb_cyc_i & wb_stb_i & ~wb_ack_o;

always @(posedge clk)

        rf_we <= #1 we & (wb_addr_i[6:2] < 5'h8);

always @(posedge clk)

        o3_we <= #1 we & (wb_addr_i[6:2] == 5'h8);

always @(posedge clk)

        o4_we <= #1 we & (wb_addr_i[6:2] == 5'h9);

always @(posedge clk)

        o6_we <= #1 we & (wb_addr_i[6:2] == 5'ha);

always @(posedge clk)

        o7_we <= #1 we & (wb_addr_i[6:2] == 5'hb);

always @(posedge clk)

        o8_we <= #1 we & (wb_addr_i[6:2] == 5'hc);

always @(posedge clk)

        o9_we <= #1 we & (wb_addr_i[6:2] == 5'hd);

always @(posedge clk)

        i3_re <= #1 re & (wb_addr_i[6:2] == 5'he);

always @(posedge clk)

        i4_re <= #1 re & (wb_addr_i[6:2] == 5'hf);

always @(posedge clk)

        i6_re <= #1 re & (wb_addr_i[6:2] == 5'h10);

endmodule