design/sys/iop/niu/rtl/niu_pio_slv_decoder.v

// ========== Copyright Header Begin ==========================================
//
// OpenSPARC T2 Processor File: niu_pio_slv_decoder.v
// Copyright (C) 1995-2007 Sun Microsystems, Inc. All Rights Reserved
// 4150 Network Circle, Santa Clara, California 95054, U.S.A.
//
// * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; version 2 of the License.
//
// This program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
// For the avoidance of doubt, and except that if any non-GPL license
// choice is available it will apply instead, Sun elects to use only
// the General Public License version 2 (GPLv2) at this time for any
// software where a choice of GPL license versions is made
// available with the language indicating that GPLv2 or any later version
// may be used, or where a choice of which version of the GPL is applied is
// otherwise unspecified.
//
// Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
// CA 95054 USA or visit www.sun.com if you need additional information or
// have any questions.
//
// ========== Copyright Header End ============================================
/*%W%   %G%*/

/*****************************************************************
 *
 * File Name    : niu_pio_slv_decoder.v
 * Author Name  : John Lo
 * Description  : It contains PIO itslef read/write decoder,
 *
 * Parent Module: niu_pio_slv_decoder.v
 * Child  Module:
 * Interface Mod: many.
 * Date Created : 3/30/04
 *
 * Copyright (c) 2020, Sun Microsystems, Inc.
 * Sun Proprietary and Confidential
 *
 * Modification :
 *
 ****************************************************************/

module niu_pio_slv_decoder (/*AUTOARG*/
   // Outputs
   slv_ack, slv_rdata, slv_err, ras_dev_func_share,
   ld_dev_func_share,rd_dev_func_share,
   // Inputs
   reset, clk, slv_sel_reg, addr, rd, dev_func_share
   );

   input                      clk;
   input                      reset;

   input                      slv_sel_reg;
                              // pio broadcast signals
   input [18:0]               addr;
   input                      rd;
   input [63:0]               dev_func_share;

   output                     slv_ack;
   output [63:0]              slv_rdata;
   output                     slv_err;
                              //
   output                     ras_dev_func_share;
   output                     ld_dev_func_share;
   output                     rd_dev_func_share;


// common reg declaration
   reg [63:0]                 rd_data;
   reg                        non_qualified_addr_err;
// common wrie declaration
   wire [63:0]                slv_rdata;
   wire                       rd_en;
   wire                       wr_en;
   wire                       rasr;
// output reg declaration
   reg                        ras_dev_func_share;
   reg                        ld_dev_func_share;
   reg                        rd_dev_func_share;

`ifdef NEPTUNE
/* ---------------------------------------------------------- */
   reg                          slv_sel_reg_int;
   reg                          rd_int;
   reg [18:0]                   addr_int;

always @(posedge clk)
 if (reset)
  begin
        slv_sel_reg_int <= 1'b0;
        rd_int          <= 1'b0;
        addr_int        <= 19'b0;
  end
 else
  begin
        slv_sel_reg_int <= slv_sel_reg ;
        rd_int          <= rd ;
        addr_int        <= addr;
  end

`else
/* ---------------------------------------------------------- */

   wire                         slv_sel_reg_int;
   wire                         rd_int;
   wire [18:0]                  addr_int;

   assign slv_sel_reg_int       = slv_sel_reg ;
   assign rd_int                = rd ;
   assign addr_int              = addr ;
/* ----------------------------------------------------------- */
`endif


niu_rw_ctl_0 slv_rw_ctl(
                      // Outputs
                      .wr_en            (wr_en),
                      .rd_en            (rd_en),
                      .ack              (slv_ack),
                      .rdata            (slv_rdata[63:0]),
                      .err              (slv_err),
                      .rasr             (rasr),
                      // Inputs
                      .clk              (clk),
                      .sel              (slv_sel_reg_int),
                      .rd               (rd_int),
                      .rd_data          (rd_data[63:0]),
                      .non_qualified_addr_err(non_qualified_addr_err));


always @ (/*AUTOSENSE*/addr_int or dev_func_share or rasr or wr_en or rd_en)
  begin
                non_qualified_addr_err = 0;
                rd_data            = 64'hdead_beef_dead_beef;
                ras_dev_func_share = 0;
                ld_dev_func_share  = 0;
                rd_dev_func_share  = 0;

    case({addr_int[18:3],3'b0}) //synopsys parallel_case full_case
    19'h1_0000: begin // device function shared register
                  ras_dev_func_share = rasr;
                  ld_dev_func_share  = wr_en;
                  rd_dev_func_share  = rd_en;
                  rd_data            = dev_func_share;

                end

    default:    begin
                  rd_data            = 64'hdead_beef_dead_beef;
                  non_qualified_addr_err = 1;
                end // case: default
    endcase // case({addr[18:3],3'b0})

  end // always @ (...

endmodule // niu_pio_slv_decoder