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

///                                                               //// 

/// Wishbone arbiter, burst-compatible                            ////

///                                                               ////

/// Simple arbiter, multi-master, multi-slave with default slave  ////

/// for chaining with peripheral arbiter                          ////

///                                                               ////

/// Julius Baxter, julius@opencores.org                           ////

///                                                               ////

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

////                                                              ////

//// Copyright (C) 2009, 2010 Authors and OPENCORES.ORG           ////

////                                                              ////

//// 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                     ////

////                                                              ////

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

`include "orpsoc-defines.v"

// 2 Masters, a few slaves

module arbiter_dbus

  (

   // or1200 data master

   // Wishbone Master interface

   wbm0_adr_o,

   wbm0_dat_o,

   wbm0_sel_o,

   wbm0_we_o,

   wbm0_cyc_o,

   wbm0_stb_o,

   wbm0_cti_o,

   wbm0_bte_o,

   wbm0_dat_i,

   wbm0_ack_i,

   wbm0_err_i,

   wbm0_rty_i,

   // or1200 debug master

   // Wishbone Master interface

   wbm1_adr_o,

   wbm1_dat_o,

   wbm1_sel_o,

   wbm1_we_o,

   wbm1_cyc_o,

   wbm1_stb_o,

   wbm1_cti_o,

   wbm1_bte_o,

   wbm1_dat_i,

   wbm1_ack_i,

   wbm1_err_i,

   wbm1_rty_i,

   // Slave one

   // Wishbone Slave interface

   wbs0_adr_i,

   wbs0_dat_i,

   wbs0_sel_i,

   wbs0_we_i,

   wbs0_cyc_i,

   wbs0_stb_i,

   wbs0_cti_i,

   wbs0_bte_i,

   wbs0_dat_o,

   wbs0_ack_o,

   wbs0_err_o,

   wbs0_rty_o,

   // Slave two

   // Wishbone Slave interface

   wbs1_adr_i,

   wbs1_dat_i,

   wbs1_sel_i,

   wbs1_we_i,

   wbs1_cyc_i,

   wbs1_stb_i,

   wbs1_cti_i,

   wbs1_bte_i,

   wbs1_dat_o,

   wbs1_ack_o,

   wbs1_err_o,

   wbs1_rty_o,

   /*

   // Slave three

   // Wishbone Slave interface

   wbs2_adr_i,

   wbs2_dat_i,

   wbs2_sel_i,

   wbs2_we_i,

   wbs2_cyc_i,

   wbs2_stb_i,

   wbs2_cti_i,

   wbs2_bte_i,

   wbs2_dat_o,

   wbs2_ack_o,

   wbs2_err_o,

   wbs2_rty_o,

   // Slave four

   // Wishbone Slave interface

   wbs3_adr_i,

   wbs3_dat_i,

   wbs3_sel_i,

   wbs3_we_i,

   wbs3_cyc_i,

   wbs3_stb_i,

   wbs3_cti_i,

   wbs3_bte_i,

   wbs3_dat_o,

   wbs3_ack_o,

   wbs3_err_o,

   wbs3_rty_o,

   // Slave five

   // Wishbone Slave interface

   wbs4_adr_i,

   wbs4_dat_i,

   wbs4_sel_i,

   wbs4_we_i,

   wbs4_cyc_i,

   wbs4_stb_i,

   wbs4_cti_i,

   wbs4_bte_i,

   wbs4_dat_o,

   wbs4_ack_o,

   wbs4_err_o,

   wbs4_rty_o,

    // Slave six

    // Wishbone Slave interface

    wbs5_adr_i,

    wbs5_dat_i,

    wbs5_sel_i,

    wbs5_we_i,

    wbs5_cyc_i,

    wbs5_stb_i,

    wbs5_cti_i,

    wbs5_bte_i,

    wbs5_dat_o,

    wbs5_ack_o,

    wbs5_err_o,

    wbs5_rty_o,

    // Slave seven

    // Wishbone Slave interface

    wbs6_adr_i,

    wbs6_dat_i,

    wbs6_sel_i,

    wbs6_we_i,

    wbs6_cyc_i,

    wbs6_stb_i,

    wbs6_cti_i,

    wbs6_bte_i,

    wbs6_dat_o,

    wbs6_ack_o,

    wbs6_err_o,

    wbs6_rty_o,

    // Slave eight

    // Wishbone Slave interface

    wbs7_adr_i,

    wbs7_dat_i,

    wbs7_sel_i,

    wbs7_we_i,

    wbs7_cyc_i,

    wbs7_stb_i,

    wbs7_cti_i,

    wbs7_bte_i,

    wbs7_dat_o,

    wbs7_ack_o,

    wbs7_err_o,

    wbs7_rty_o,

    // Slave nine

    // Wishbone Slave interface

    wbs8_adr_i,

    wbs8_dat_i,

    wbs8_sel_i,

    wbs8_we_i,

    wbs8_cyc_i,

    wbs8_stb_i,

    wbs8_cti_i,

    wbs8_bte_i,

    wbs8_dat_o,

    wbs8_ack_o,

    wbs8_err_o,

    wbs8_rty_o,

    // Slave ten

    // Wishbone Slave interface

    wbs9_adr_i,

    wbs9_dat_i,

    wbs9_sel_i,

    wbs9_we_i,

    wbs9_cyc_i,

    wbs9_stb_i,

    wbs9_cti_i,

    wbs9_bte_i,

    wbs9_dat_o,

    wbs9_ack_o,

    wbs9_err_o,

    wbs9_rty_o,

    // Slave eleven

    // Wishbone Slave interface

    wbs10_adr_i,

    wbs10_dat_i,

    wbs10_sel_i,

    wbs10_we_i,

    wbs10_cyc_i,

    wbs10_stb_i,

    wbs10_cti_i,

    wbs10_bte_i,

    wbs10_dat_o,

    wbs10_ack_o,

    wbs10_err_o,

    wbs10_rty_o,

    // Slave twelve

    // Wishbone Slave interface

    wbs11_adr_i,

    wbs11_dat_i,

    wbs11_sel_i,

    wbs11_we_i,

    wbs11_cyc_i,

    wbs11_stb_i,

    wbs11_cti_i,

    wbs11_bte_i,

    wbs11_dat_o,

    wbs11_ack_o,

    wbs11_err_o,

    wbs11_rty_o,

    // Slave thirteen

    // Wishbone Slave interface

    wbs12_adr_i,

    wbs12_dat_i,

    wbs12_sel_i,

    wbs12_we_i,

    wbs12_cyc_i,

    wbs12_stb_i,

    wbs12_cti_i,

    wbs12_bte_i,

    wbs12_dat_o,

    wbs12_ack_o,

    wbs12_err_o,

    wbs12_rty_o,

    // Slave fourteen

    // Wishbone Slave interface

    wbs13_adr_i,

    wbs13_dat_i,

    wbs13_sel_i,

    wbs13_we_i,

    wbs13_cyc_i,

    wbs13_stb_i,

    wbs13_cti_i,

    wbs13_bte_i,

    wbs13_dat_o,

    wbs13_ack_o,

    wbs13_err_o,

    wbs13_rty_o,

    // Slave fifteen

    // Wishbone Slave interface

    wbs14_adr_i,

    wbs14_dat_i,

    wbs14_sel_i,

    wbs14_we_i,

    wbs14_cyc_i,

    wbs14_stb_i,

    wbs14_cti_i,

    wbs14_bte_i,

    wbs14_dat_o,

    wbs14_ack_o,

    wbs14_err_o,

    wbs14_rty_o,

    // Slave sixteen

    // Wishbone Slave interface

    wbs15_adr_i,

    wbs15_dat_i,

    wbs15_sel_i,

    wbs15_we_i,

    wbs15_cyc_i,

    wbs15_stb_i,

    wbs15_cti_i,

    wbs15_bte_i,

    wbs15_dat_o,

    wbs15_ack_o,

    wbs15_err_o,

    wbs15_rty_o,

    // Slave seventeen

    // Wishbone Slave interface

    wbs16_adr_i,

    wbs16_dat_i,

    wbs16_sel_i,

    wbs16_we_i,

    wbs16_cyc_i,

    wbs16_stb_i,

    wbs16_cti_i,

    wbs16_bte_i,

    wbs16_dat_o,

    wbs16_ack_o,

    wbs16_err_o,

    wbs16_rty_o,

    */

   wb_clk,

   wb_rst

   );

   parameter wb_dat_width = 32;

   parameter wb_adr_width = 32;

   parameter wb_addr_match_width = 8;

   parameter wb_num_slaves = 2; // must also (un)comment things if changing

   // Slave addresses - these should be defparam'd from top level

   // Declare them as you need them

   parameter slave0_adr = 0;

   parameter slave1_adr = 0;

   parameter slave2_adr = 0;

   parameter slave3_adr = 0;

   parameter slave4_adr = 0;

   parameter slave5_adr = 0;

   parameter slave6_adr = 0;

   parameter slave7_adr = 0;

   parameter slave8_adr = 0;

   parameter slave9_adr = 0;

   parameter slave10_adr = 0;

   parameter slave11_adr = 0;

   parameter slave12_adr = 0;

   // Select for slave 0

`define WB_ARB_ADDR_MATCH_SEL_SLAVE0 wb_adr_width-1:wb_adr_width-4

`define WB_ARB_ADDR_MATCH_SEL wb_adr_width-1:wb_adr_width-wb_addr_match_width

   input wb_clk;

   input wb_rst;

   // WB Master one

   input [wb_adr_width-1:0] wbm0_adr_o;

   input [wb_dat_width-1:0] wbm0_dat_o;

   input [3:0]               wbm0_sel_o;

   input                    wbm0_we_o;

   input                    wbm0_cyc_o;

   input                    wbm0_stb_o;

   input [2:0]               wbm0_cti_o;

   input [1:0]               wbm0_bte_o;

   output [wb_dat_width-1:0] wbm0_dat_i;

   output                    wbm0_ack_i;

   output                    wbm0_err_i;

   output                    wbm0_rty_i;

   input [wb_adr_width-1:0]  wbm1_adr_o;

   input [wb_dat_width-1:0]  wbm1_dat_o;

   input [3:0]                wbm1_sel_o;

   input                     wbm1_we_o;

   input                     wbm1_cyc_o;

   input                     wbm1_stb_o;

   input [2:0]                wbm1_cti_o;

   input [1:0]                wbm1_bte_o;

   output [wb_dat_width-1:0] wbm1_dat_i;

   output                    wbm1_ack_i;

   output                    wbm1_err_i;

   output                    wbm1_rty_i;

   // Slave one

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs0_adr_i;

   output [wb_dat_width-1:0] wbs0_dat_i;

   output [3:0]               wbs0_sel_i;

   output                    wbs0_we_i;

   output                    wbs0_cyc_i;

   output                    wbs0_stb_i;

   output [2:0]       wbs0_cti_i;

   output [1:0]       wbs0_bte_i;

   input [wb_dat_width-1:0]  wbs0_dat_o;

   input                     wbs0_ack_o;

   input                     wbs0_err_o;

   input                     wbs0_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs1_adr_i;

   output [wb_dat_width-1:0] wbs1_dat_i;

   output [3:0]               wbs1_sel_i;

   output                    wbs1_we_i;

   output                    wbs1_cyc_i;

   output                    wbs1_stb_i;

   output [2:0]       wbs1_cti_i;

   output [1:0]       wbs1_bte_i;

   input [wb_dat_width-1:0]  wbs1_dat_o;

   input                     wbs1_ack_o;

   input                     wbs1_err_o;

   input                     wbs1_rty_o;

/*

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs2_adr_i;

   output [wb_dat_width-1:0] wbs2_dat_i;

   output [3:0]              wbs2_sel_i;

   output                    wbs2_we_i;

   output                    wbs2_cyc_i;

   output                    wbs2_stb_i;

   output [2:0]              wbs2_cti_i;

   output [1:0]              wbs2_bte_i;

   input [wb_dat_width-1:0]  wbs2_dat_o;

   input                     wbs2_ack_o;

   input                     wbs2_err_o;

   input                     wbs2_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs3_adr_i;

   output [wb_dat_width-1:0] wbs3_dat_i;

   output [3:0]              wbs3_sel_i;

   output                    wbs3_we_i;

   output                    wbs3_cyc_i;

   output                    wbs3_stb_i;

   output [2:0]              wbs3_cti_i;

   output [1:0]              wbs3_bte_i;

   input [wb_dat_width-1:0]  wbs3_dat_o;

   input                     wbs3_ack_o;

   input                     wbs3_err_o;

   input                     wbs3_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs4_adr_i;

   output [wb_dat_width-1:0] wbs4_dat_i;

   output [3:0]              wbs4_sel_i;

   output                    wbs4_we_i;

   output                    wbs4_cyc_i;

   output                    wbs4_stb_i;

   output [2:0]              wbs4_cti_i;

   output [1:0]              wbs4_bte_i;

   input [wb_dat_width-1:0]  wbs4_dat_o;

   input                     wbs4_ack_o;

   input                     wbs4_err_o;

   input                     wbs4_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs5_adr_i;

   output [wb_dat_width-1:0] wbs5_dat_i;

   output [3:0]              wbs5_sel_i;

   output                    wbs5_we_i;

   output                    wbs5_cyc_i;

   output                    wbs5_stb_i;

   output [2:0]              wbs5_cti_i;

   output [1:0]              wbs5_bte_i;

   input [wb_dat_width-1:0]  wbs5_dat_o;

   input                     wbs5_ack_o;

   input                     wbs5_err_o;

   input                     wbs5_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs6_adr_i;

   output [wb_dat_width-1:0] wbs6_dat_i;

   output [3:0]              wbs6_sel_i;

   output                    wbs6_we_i;

   output                    wbs6_cyc_i;

   output                    wbs6_stb_i;

   output [2:0]              wbs6_cti_i;

   output [1:0]              wbs6_bte_i;

   input [wb_dat_width-1:0]  wbs6_dat_o;

   input                     wbs6_ack_o;

   input                     wbs6_err_o;

   input                     wbs6_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs7_adr_i;

   output [wb_dat_width-1:0] wbs7_dat_i;

   output [3:0]              wbs7_sel_i;

   output                    wbs7_we_i;

   output                    wbs7_cyc_i;

   output                    wbs7_stb_i;

   output [2:0]              wbs7_cti_i;

   output [1:0]              wbs7_bte_i;

   input [wb_dat_width-1:0]  wbs7_dat_o;

   input                     wbs7_ack_o;

   input                     wbs7_err_o;

   input                     wbs7_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs8_adr_i;

   output [wb_dat_width-1:0] wbs8_dat_i;

   output [3:0]              wbs8_sel_i;

   output                    wbs8_we_i;

   output                    wbs8_cyc_i;

   output                    wbs8_stb_i;

   output [2:0]              wbs8_cti_i;

   output [1:0]              wbs8_bte_i;

   input [wb_dat_width-1:0]  wbs8_dat_o;

   input                     wbs8_ack_o;

   input                     wbs8_err_o;

   input                     wbs8_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs9_adr_i;

   output [wb_dat_width-1:0] wbs9_dat_i;

   output [3:0]              wbs9_sel_i;

   output                    wbs9_we_i;

   output                    wbs9_cyc_i;

   output                    wbs9_stb_i;

   output [2:0]              wbs9_cti_i;

   output [1:0]              wbs9_bte_i;

   input [wb_dat_width-1:0]  wbs9_dat_o;

   input                     wbs9_ack_o;

   input                     wbs9_err_o;

   input                     wbs9_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs10_adr_i;

   output [wb_dat_width-1:0] wbs10_dat_i;

   output [3:0]              wbs10_sel_i;

   output                    wbs10_we_i;

   output                    wbs10_cyc_i;

   output                    wbs10_stb_i;

   output [2:0]              wbs10_cti_i;

   output [1:0]              wbs10_bte_i;

   input [wb_dat_width-1:0]  wbs10_dat_o;

   input                     wbs10_ack_o;

   input                     wbs10_err_o;

   input                     wbs10_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs11_adr_i;

   output [wb_dat_width-1:0] wbs11_dat_i;

   output [3:0]              wbs11_sel_i;

   output                    wbs11_we_i;

   output                    wbs11_cyc_i;

   output                    wbs11_stb_i;

   output [2:0]              wbs11_cti_i;

   output [1:0]              wbs11_bte_i;

   input [wb_dat_width-1:0]  wbs11_dat_o;

   input                     wbs11_ack_o;

   input                     wbs11_err_o;

   input                     wbs11_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs12_adr_i;

   output [wb_dat_width-1:0] wbs12_dat_i;

   output [3:0]              wbs12_sel_i;

   output                    wbs12_we_i;

   output                    wbs12_cyc_i;

   output                    wbs12_stb_i;

   output [2:0]              wbs12_cti_i;

   output [1:0]              wbs12_bte_i;

   input [wb_dat_width-1:0]  wbs12_dat_o;

   input                     wbs12_ack_o;

   input                     wbs12_err_o;

   input                     wbs12_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs13_adr_i;

   output [wb_dat_width-1:0] wbs13_dat_i;

   output [3:0]              wbs13_sel_i;

   output                    wbs13_we_i;

   output                    wbs13_cyc_i;

   output                    wbs13_stb_i;

   output [2:0]              wbs13_cti_i;

   output [1:0]              wbs13_bte_i;

   input [wb_dat_width-1:0]  wbs13_dat_o;

   input                     wbs13_ack_o;

   input                     wbs13_err_o;

   input                     wbs13_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs14_adr_i;

   output [wb_dat_width-1:0] wbs14_dat_i;

   output [3:0]              wbs14_sel_i;

   output                    wbs14_we_i;

   output                    wbs14_cyc_i;

   output                    wbs14_stb_i;

   output [2:0]              wbs14_cti_i;

   output [1:0]              wbs14_bte_i;

   input [wb_dat_width-1:0]  wbs14_dat_o;

   input                     wbs14_ack_o;

   input                     wbs14_err_o;

   input                     wbs14_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs15_adr_i;

   output [wb_dat_width-1:0] wbs15_dat_i;

   output [3:0]              wbs15_sel_i;

   output                    wbs15_we_i;

   output                    wbs15_cyc_i;

   output                    wbs15_stb_i;

   output [2:0]              wbs15_cti_i;

   output [1:0]              wbs15_bte_i;

   input [wb_dat_width-1:0]  wbs15_dat_o;

   input                     wbs15_ack_o;

   input                     wbs15_err_o;

   input                     wbs15_rty_o;

   // Wishbone Slave interface

   output [wb_adr_width-1:0] wbs16_adr_i;

   output [wb_dat_width-1:0] wbs16_dat_i;

   output [3:0]              wbs16_sel_i;

   output                    wbs16_we_i;

   output                    wbs16_cyc_i;

   output                    wbs16_stb_i;

   output [2:0]              wbs16_cti_i;

   output [1:0]              wbs16_bte_i;

   input [wb_dat_width-1:0]  wbs16_dat_o;

   input                     wbs16_ack_o;

   input                     wbs16_err_o;

   input                     wbs16_rty_o;

*/

   reg               watchdog_err;

`ifdef ARBITER_DBUS_REGISTERING

   // Registering setup:

   // Masters typically register their outputs, so do the master selection and

   // muxing before registering in the arbiter. Keep the common parts outside

   // for code brevity.

   // Master ins -> |MUX> -> these wires

   wire [wb_adr_width-1:0]   wbm_adr_o_w;

   wire [wb_dat_width-1:0]   wbm_dat_o_w;

   wire [3:0]                 wbm_sel_o_w;

   wire                      wbm_we_o_w;

   wire                      wbm_cyc_o_w;

   wire                      wbm_stb_o_w;

   wire [2:0]                 wbm_cti_o_w;

   wire [1:0]                 wbm_bte_o_w;

   // Slave ins -> |MUX> -> these wires

   wire [wb_dat_width-1:0]   wbm_dat_i;

   wire                      wbm_ack_i;

   wire                      wbm_err_i;

   wire                      wbm_rty_i;

   // Registers after masters input mux

   reg [wb_adr_width-1:0]    wbm_adr_o_r;

   reg [wb_dat_width-1:0]    wbm_dat_o_r;

   reg [3:0]                  wbm_sel_o_r;

   reg                       wbm_we_o_r;

   reg                       wbm_cyc_o_r;

   reg                       wbm_stb_o_r;

   reg [2:0]                  wbm_cti_o_r;

   reg [1:0]                  wbm_bte_o_r;

   // Master input mux register wires

   wire [wb_adr_width-1:0]   wbm_adr_o;

   wire [wb_dat_width-1:0]   wbm_dat_o;

   wire [3:0]                 wbm_sel_o;

   wire                      wbm_we_o;

   wire                      wbm_cyc_o;

   wire                      wbm_stb_o;

   wire [2:0]                 wbm_cti_o;

   wire [1:0]                 wbm_bte_o;

   // Registers after slaves input mux

   reg [wb_dat_width-1:0]    wbm_dat_i_r;

   reg                       wbm_ack_i_r;

   reg                       wbm_err_i_r;

   reg                       wbm_rty_i_r;

   // Master select (MUX controls)

   wire [1:0]                 master_sel;

   // priority to wbm1, the debug master

   assign master_sel[0] = wbm0_cyc_o & !wbm1_cyc_o;

   assign master_sel[1] = wbm1_cyc_o;

   // Master input mux, priority to debug master

   assign wbm_adr_o_w = master_sel[1] ? wbm1_adr_o :

                      wbm0_adr_o;

   assign wbm_dat_o_w = master_sel[1] ? wbm1_dat_o :

                      wbm0_dat_o;

   assign wbm_sel_o_w = master_sel[1] ? wbm1_sel_o :

                      wbm0_sel_o;

   assign wbm_we_o_w = master_sel[1] ? wbm1_we_o :

                      wbm0_we_o;

   assign wbm_cyc_o_w = master_sel[1] ? wbm1_cyc_o :

                      wbm0_cyc_o;

   assign wbm_stb_o_w = master_sel[1] ? wbm1_stb_o :

                     wbm0_stb_o;

   assign wbm_cti_o_w = master_sel[1] ? wbm1_cti_o :

                     wbm0_cti_o;

   assign wbm_bte_o_w = master_sel[1] ? wbm1_bte_o :

                      wbm0_bte_o;

   // Register muxed master signals

   always @(posedge wb_clk)

     begin

        wbm_adr_o_r <= wbm_adr_o_w;

        wbm_dat_o_r <= wbm_dat_o_w;

        wbm_sel_o_r <= wbm_sel_o_w;

        wbm_we_o_r <= wbm_we_o_w;

        wbm_cyc_o_r <= wbm_cyc_o_w;

        wbm_stb_o_r <= wbm_stb_o_w & !wbm_ack_i & !wbm_ack_i_r;

        wbm_cti_o_r <= wbm_cti_o_w;

        wbm_bte_o_r <= wbm_bte_o_w;

        wbm_dat_i_r <= wbm_dat_i;

        wbm_ack_i_r <= wbm_ack_i;

        wbm_err_i_r <= wbm_err_i;

        wbm_rty_i_r <= wbm_rty_i;

     end // always @ (posedge wb_clk)

   assign wbm_adr_o = wbm_adr_o_r;

   assign wbm_dat_o = wbm_dat_o_r;

   assign wbm_sel_o = wbm_sel_o_r;

   assign wbm_we_o = wbm_we_o_r;

   assign wbm_cyc_o = wbm_cyc_o_r;

   assign wbm_stb_o = wbm_stb_o_r;

   assign wbm_cti_o = wbm_cti_o_r;

   assign wbm_bte_o = wbm_bte_o_r;

   // Master input mux, priority to debug master

   assign wbm0_dat_i = wbm_dat_i_r;

   assign wbm0_ack_i = wbm_ack_i_r & master_sel[0];

   assign wbm0_err_i = wbm_err_i_r & master_sel[0];

   assign wbm0_rty_i = wbm_rty_i_r & master_sel[0];

   assign wbm1_dat_i = wbm_dat_i_r;

   assign wbm1_ack_i = wbm_ack_i_r & master_sel[1];

   assign wbm1_err_i = wbm_err_i_r & master_sel[1];

   assign wbm1_rty_i = wbm_rty_i_r & master_sel[1];

`else // !`ifdef ARBITER_DBUS_REGISTERING

   // Master input mux output wires

   wire [wb_adr_width-1:0]   wbm_adr_o;

   wire [wb_dat_width-1:0]   wbm_dat_o;

   wire [3:0]                 wbm_sel_o;

   wire                      wbm_we_o;

   wire                      wbm_cyc_o;

   wire                      wbm_stb_o;

   wire [2:0]                 wbm_cti_o;

   wire [1:0]                 wbm_bte_o;

   // Master select

   wire [1:0]                 master_sel;

   // priority to wbm1, the debug master

   assign master_sel[0] = wbm0_cyc_o & !wbm1_cyc_o;

   assign master_sel[1] = wbm1_cyc_o;

   // Master input mux, priority to debug master

   assign wbm_adr_o = master_sel[1] ? wbm1_adr_o :

                      wbm0_adr_o;

   assign wbm_dat_o = master_sel[1] ? wbm1_dat_o :

                      wbm0_dat_o;