source: XOpenSparcT1/trunk/WB/wb_conbus_top.v @ 22

/////////////////////////////////////////////////////////////////////
////                                                             ////
////  WISHBONE Connection Bus Top Level                          ////
////                                                             ////
////                                                             ////
////  Author: Johny Chi                                          ////
////          chisuhua@yahoo.com.cn                              ////
////                                                             ////
////                                                             ////
////                                                             ////
/////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2000 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                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
//
//  Description
//      1. Up to 8 masters and 8 slaves share bus Wishbone connection
//      2. no priorty arbitor , 8 masters are processed in a round
//         robin way,
//      3. if WB_USE_TRISTATE was defined, the share bus is a tristate
//         bus, and use less logic resource.
//      4. wb_conbus was synthesis to XC2S100-5-PQ208 using synplify,
//     Max speed >60M , and 374 SLICE if using Multiplexor bus
//              or 150 SLICE if using tri-state bus.
//
`include "wb_conbus_defines.v"
`define                 dw       64             // Data bus Width
`define                 aw       64             // Address bus Width
`define                 sw   `dw / 8    // Number of Select Lines
`define                 mbusw  `aw + `sw + `dw +4       //address width + byte select width + dat width + cyc + we + stb +cab , input from master interface
`define                 sbusw    3      //  ack + err + rty, input from slave interface
`define                 mselectw  8     // number of masters
`define                 sselectw  8     // number of slavers

//`define               WB_USE_TRISTATE


module wb_conbus_top(
        clk_i, rst_i,

        // Master 0 Interface
        m0_dat_i, m0_dat_o, m0_adr_i, m0_sel_i, m0_we_i, m0_cyc_i,
        m0_stb_i, m0_ack_o, m0_err_o, m0_rty_o, m0_cab_i,

        // Master 1 Interface
        m1_dat_i, m1_dat_o, m1_adr_i, m1_sel_i, m1_we_i, m1_cyc_i,
        m1_stb_i, m1_ack_o, m1_err_o, m1_rty_o, m1_cab_i,

        // Master 2 Interface
        m2_dat_i, m2_dat_o, m2_adr_i, m2_sel_i, m2_we_i, m2_cyc_i,
        m2_stb_i, m2_ack_o, m2_err_o, m2_rty_o, m2_cab_i,

        // Master 3 Interface
        m3_dat_i, m3_dat_o, m3_adr_i, m3_sel_i, m3_we_i, m3_cyc_i,
        m3_stb_i, m3_ack_o, m3_err_o, m3_rty_o, m3_cab_i,

        // Master 4 Interface
        m4_dat_i, m4_dat_o, m4_adr_i, m4_sel_i, m4_we_i, m4_cyc_i,
        m4_stb_i, m4_ack_o, m4_err_o, m4_rty_o, m4_cab_i,

        // Master 5 Interface
        m5_dat_i, m5_dat_o, m5_adr_i, m5_sel_i, m5_we_i, m5_cyc_i,
        m5_stb_i, m5_ack_o, m5_err_o, m5_rty_o, m5_cab_i,

        // Master 6 Interface
        m6_dat_i, m6_dat_o, m6_adr_i, m6_sel_i, m6_we_i, m6_cyc_i,
        m6_stb_i, m6_ack_o, m6_err_o, m6_rty_o, m6_cab_i,

        // Master 7 Interface
        m7_dat_i, m7_dat_o, m7_adr_i, m7_sel_i, m7_we_i, m7_cyc_i,
        m7_stb_i, m7_ack_o, m7_err_o, m7_rty_o, m7_cab_i,

        // Slave 0 Interface
        s0_dat_i, s0_dat_o, s0_adr_o, s0_sel_o, s0_we_o, s0_cyc_o,
        s0_stb_o, s0_ack_i, s0_err_i, s0_rty_i, s0_cab_o,

        // Slave 1 Interface
        s1_dat_i, s1_dat_o, s1_adr_o, s1_sel_o, s1_we_o, s1_cyc_o,
        s1_stb_o, s1_ack_i, s1_err_i, s1_rty_i, s1_cab_o,

        // Slave 2 Interface
        s2_dat_i, s2_dat_o, s2_adr_o, s2_sel_o, s2_we_o, s2_cyc_o,
        s2_stb_o, s2_ack_i, s2_err_i, s2_rty_i, s2_cab_o,

        // Slave 3 Interface
        s3_dat_i, s3_dat_o, s3_adr_o, s3_sel_o, s3_we_o, s3_cyc_o,
        s3_stb_o, s3_ack_i, s3_err_i, s3_rty_i, s3_cab_o,

        // Slave 4 Interface
        s4_dat_i, s4_dat_o, s4_adr_o, s4_sel_o, s4_we_o, s4_cyc_o,
        s4_stb_o, s4_ack_i, s4_err_i, s4_rty_i, s4_cab_o,

        // Slave 5 Interface
        s5_dat_i, s5_dat_o, s5_adr_o, s5_sel_o, s5_we_o, s5_cyc_o,
        s5_stb_o, s5_ack_i, s5_err_i, s5_rty_i, s5_cab_o,

        // Slave 6 Interface
        s6_dat_i, s6_dat_o, s6_adr_o, s6_sel_o, s6_we_o, s6_cyc_o,
        s6_stb_o, s6_ack_i, s6_err_i, s6_rty_i, s6_cab_o,

        // Slave 7 Interface
        s7_dat_i, s7_dat_o, s7_adr_o, s7_sel_o, s7_we_o, s7_cyc_o,
        s7_stb_o, s7_ack_i, s7_err_i, s7_rty_i, s7_cab_o

        );

////////////////////////////////////////////////////////////////////
//
// Module Parameters
//


// address for DDR from 0x0 to 0x7fffffff_ffffffff (64'h00000000_00000000 to 64'h7fffffff_ffffffff)
parameter               s0_addr_w = 1 ;                 // slave 0 address decode width
parameter               s0_addr = 1'b0; // slave 0 address

//address for a 32MB flash from 0x800000ff_f0800000 to 0x800000ff_f0ffffff 
//Check address_w 
// 32 MB --> 8 MW X32 bits --> 2^23 --> addr_w=64-23=41 
parameter               s1_addr_w = 41 ;                        // slave 1 address decode width
parameter               s1_addr = {40'h800000FFF0,1'b0};        // slave 1 address 

parameter               s2_addr_w = 56 ;                   
parameter               s2_addr = {56'h800000FFF0C2C1};         // slave 2 address
parameter               s3_addr_w = 60 ;                   
parameter               s3_addr = {60'h800000FFF0C2C00};        // slave 3 address
parameter               s4_addr_w = 37 ;                   
parameter               s4_addr = {36'h800000FFF,1'b1};         // slave 4 address
parameter               s5_addr_w = 60 ;                   
parameter               s5_addr = {60'h400000F00000000};        // slave 5 address
parameter               s6_addr_w = 60 ;                   
parameter               s6_addr = {60'h500000F00000000};        // slave 6 address
parameter               s7_addr_w = 60 ;                   
parameter               s7_addr = {60'h600000F00000000};        // slave 7 address


////////////////////////////////////////////////////////////////////
//
// Module IOs
//

input           clk_i, rst_i;

// Master 0 Interface
input   [`dw-1:0]       m0_dat_i;
output  [`dw-1:0]       m0_dat_o;
input   [`aw-1:0]       m0_adr_i;
input   [`sw-1:0]       m0_sel_i;
input                   m0_we_i;
input                   m0_cyc_i;
input                   m0_stb_i;
input                   m0_cab_i;
output                  m0_ack_o;
output                  m0_err_o;
output                  m0_rty_o;

// Master 1 Interface
input   [`dw-1:0]       m1_dat_i;
output  [`dw-1:0]       m1_dat_o;
input   [`aw-1:0]       m1_adr_i;
input   [`sw-1:0]       m1_sel_i;
input                   m1_we_i;
input                   m1_cyc_i;
input                   m1_stb_i;
input                   m1_cab_i;
output                  m1_ack_o;
output                  m1_err_o;
output                  m1_rty_o;

// Master 2 Interface
input   [`dw-1:0]       m2_dat_i;
output  [`dw-1:0]       m2_dat_o;
input   [`aw-1:0]       m2_adr_i;
input   [`sw-1:0]       m2_sel_i;
input                   m2_we_i;
input                   m2_cyc_i;
input                   m2_stb_i;
input                   m2_cab_i;
output                  m2_ack_o;
output                  m2_err_o;
output                  m2_rty_o;

// Master 3 Interface
input   [`dw-1:0]       m3_dat_i;
output  [`dw-1:0]       m3_dat_o;
input   [`aw-1:0]       m3_adr_i;
input   [`sw-1:0]       m3_sel_i;
input                   m3_we_i;
input                   m3_cyc_i;
input                   m3_stb_i;
input                   m3_cab_i;
output                  m3_ack_o;
output                  m3_err_o;
output                  m3_rty_o;

// Master 4 Interface
input   [`dw-1:0]       m4_dat_i;
output  [`dw-1:0]       m4_dat_o;
input   [`aw-1:0]       m4_adr_i;
input   [`sw-1:0]       m4_sel_i;
input                   m4_we_i;
input                   m4_cyc_i;
input                   m4_stb_i;
input                   m4_cab_i;
output                  m4_ack_o;
output                  m4_err_o;
output                  m4_rty_o;

// Master 5 Interface
input   [`dw-1:0]       m5_dat_i;
output  [`dw-1:0]       m5_dat_o;
input   [`aw-1:0]       m5_adr_i;
input   [`sw-1:0]       m5_sel_i;
input                   m5_we_i;
input                   m5_cyc_i;
input                   m5_stb_i;
input                   m5_cab_i;
output                  m5_ack_o;
output                  m5_err_o;
output                  m5_rty_o;

// Master 6 Interface
input   [`dw-1:0]       m6_dat_i;
output  [`dw-1:0]       m6_dat_o;
input   [`aw-1:0]       m6_adr_i;
input   [`sw-1:0]       m6_sel_i;
input                   m6_we_i;
input                   m6_cyc_i;
input                   m6_stb_i;
input                   m6_cab_i;
output                  m6_ack_o;
output                  m6_err_o;
output                  m6_rty_o;

// Master 7 Interface
input   [`dw-1:0]       m7_dat_i;
output  [`dw-1:0]       m7_dat_o;
input   [`aw-1:0]       m7_adr_i;
input   [`sw-1:0]       m7_sel_i;
input                   m7_we_i;
input                   m7_cyc_i;
input                   m7_stb_i;
input                   m7_cab_i;
output                  m7_ack_o;
output                  m7_err_o;
output                  m7_rty_o;

// Slave 0 Interface
input   [`dw-1:0]       s0_dat_i;
output  [`dw-1:0]       s0_dat_o;
output  [`aw-1:0]       s0_adr_o;
output  [`sw-1:0]       s0_sel_o;
output                  s0_we_o;
output                  s0_cyc_o;
output                  s0_stb_o;
output                  s0_cab_o;
input                   s0_ack_i;
input                   s0_err_i;
input                   s0_rty_i;

// Slave 1 Interface
input   [`dw-1:0]       s1_dat_i;
output  [`dw-1:0]       s1_dat_o;
output  [`aw-1:0]       s1_adr_o;
output  [`sw-1:0]       s1_sel_o;
output                  s1_we_o;
output                  s1_cyc_o;
output                  s1_stb_o;
output                  s1_cab_o;
input                   s1_ack_i;
input                   s1_err_i;
input                   s1_rty_i;

// Slave 2 Interface
input   [`dw-1:0]       s2_dat_i;
output  [`dw-1:0]       s2_dat_o;
output  [`aw-1:0]       s2_adr_o;
output  [`sw-1:0]       s2_sel_o;
output                  s2_we_o;
output                  s2_cyc_o;
output                  s2_stb_o;
output                  s2_cab_o;
input                   s2_ack_i;
input                   s2_err_i;
input                   s2_rty_i;

// Slave 3 Interface
input   [`dw-1:0]       s3_dat_i;
output  [`dw-1:0]       s3_dat_o;
output  [`aw-1:0]       s3_adr_o;
output  [`sw-1:0]       s3_sel_o;
output                  s3_we_o;
output                  s3_cyc_o;
output                  s3_stb_o;
output                  s3_cab_o;
input                   s3_ack_i;
input                   s3_err_i;
input                   s3_rty_i;

// Slave 4 Interface
input   [`dw-1:0]       s4_dat_i;
output  [`dw-1:0]       s4_dat_o;
output  [`aw-1:0]       s4_adr_o;
output  [`sw-1:0]       s4_sel_o;
output                  s4_we_o;
output                  s4_cyc_o;
output                  s4_stb_o;
output                  s4_cab_o;
input                   s4_ack_i;
input                   s4_err_i;
input                   s4_rty_i;

// Slave 5 Interface
input   [`dw-1:0]       s5_dat_i;
output  [`dw-1:0]       s5_dat_o;
output  [`aw-1:0]       s5_adr_o;
output  [`sw-1:0]       s5_sel_o;
output                  s5_we_o;
output                  s5_cyc_o;
output                  s5_stb_o;
output                  s5_cab_o;
input                   s5_ack_i;
input                   s5_err_i;
input                   s5_rty_i;

// Slave 6 Interface
input   [`dw-1:0]       s6_dat_i;
output  [`dw-1:0]       s6_dat_o;
output  [`aw-1:0]       s6_adr_o;
output  [`sw-1:0]       s6_sel_o;
output                  s6_we_o;
output                  s6_cyc_o;
output                  s6_stb_o;
output                  s6_cab_o;
input                   s6_ack_i;
input                   s6_err_i;
input                   s6_rty_i;

// Slave 7 Interface
input   [`dw-1:0]       s7_dat_i;
output  [`dw-1:0]       s7_dat_o;
output  [`aw-1:0]       s7_adr_o;
output  [`sw-1:0]       s7_sel_o;
output                  s7_we_o;
output                  s7_cyc_o;
output                  s7_stb_o;
output                  s7_cab_o;
input                   s7_ack_i;
input                   s7_err_i;
input                   s7_rty_i;


////////////////////////////////////////////////////////////////////
//
// Local wires
//

wire    [`mselectw -1:0]        i_gnt_arb;
wire    [2:0]   gnt;
reg     [`sselectw -1:0]        i_ssel_dec;
`ifdef  WB_USE_TRISTATE
wire    [`mbusw -1:0]   i_bus_m;
`else
reg             [`mbusw -1:0]   i_bus_m;                // internal share bus, master data and control to slave
`endif
wire            [`dw -1:0]              i_dat_s;        // internal share bus , slave data to master
wire    [`sbusw -1:0]   i_bus_s;                        // internal share bus , slave control to master



////////////////////////////////////////////////////////////////////
//
// Master output Interfaces
//

// master0
assign  m0_dat_o = i_dat_s;
assign  {m0_ack_o, m0_err_o, m0_rty_o} = i_bus_s & {3{i_gnt_arb[0]}};

// master1
assign  m1_dat_o = i_dat_s;
assign  {m1_ack_o, m1_err_o, m1_rty_o} = i_bus_s & {3{i_gnt_arb[1]}};

// master2

assign  m2_dat_o = i_dat_s;
assign  {m2_ack_o, m2_err_o, m2_rty_o} = i_bus_s & {3{i_gnt_arb[2]}};

// master3

assign  m3_dat_o = i_dat_s;
assign  {m3_ack_o, m3_err_o, m3_rty_o} = i_bus_s & {3{i_gnt_arb[3]}};

// master4

assign  m4_dat_o = i_dat_s;
assign  {m4_ack_o, m4_err_o, m4_rty_o} = i_bus_s & {3{i_gnt_arb[4]}};

// master5

assign  m5_dat_o = i_dat_s;
assign  {m5_ack_o, m5_err_o, m5_rty_o} = i_bus_s & {3{i_gnt_arb[5]}};

// master6

assign  m6_dat_o = i_dat_s;
assign  {m6_ack_o, m6_err_o, m6_rty_o} = i_bus_s & {3{i_gnt_arb[6]}};

// master7

assign  m7_dat_o = i_dat_s;
assign  {m7_ack_o, m7_err_o, m7_rty_o} = i_bus_s & {3{i_gnt_arb[7]}};


assign  i_bus_s = {s0_ack_i | s1_ack_i | s2_ack_i | s3_ack_i | s4_ack_i | s5_ack_i | s6_ack_i | s7_ack_i ,
                                   s0_err_i | s1_err_i | s2_err_i | s3_err_i | s4_err_i | s5_err_i | s6_err_i | s7_err_i ,
                                   s0_rty_i | s1_rty_i | s2_rty_i | s3_rty_i | s4_rty_i | s5_rty_i | s6_rty_i | s7_rty_i };

////////////////////////////////
//      Slave output interface
//
// slave0
assign  {s0_adr_o, s0_sel_o, s0_dat_o, s0_we_o, s0_cab_o,s0_cyc_o} = i_bus_m[`mbusw -1:1];
assign  s0_stb_o = i_bus_m[1] & i_bus_m[0] & i_ssel_dec[0];  // stb_o = cyc_i & stb_i & i_ssel_dec

// slave1

assign  {s1_adr_o, s1_sel_o, s1_dat_o, s1_we_o, s1_cab_o, s1_cyc_o} = i_bus_m[`mbusw -1:1];
assign  s1_stb_o = i_bus_m[1] & i_bus_m[0] & i_ssel_dec[1];

// slave2

assign  {s2_adr_o, s2_sel_o, s2_dat_o, s2_we_o, s2_cab_o, s2_cyc_o} = i_bus_m[`mbusw -1:1];
assign  s2_stb_o = i_bus_m[1] & i_bus_m[0] & i_ssel_dec[2];

// slave3

assign  {s3_adr_o, s3_sel_o, s3_dat_o, s3_we_o, s3_cab_o, s3_cyc_o} = i_bus_m[`mbusw -1:1];
assign  s3_stb_o = i_bus_m[1] & i_bus_m[0] & i_ssel_dec[3];

// slave4

assign  {s4_adr_o, s4_sel_o, s4_dat_o, s4_we_o, s4_cab_o, s4_cyc_o} = i_bus_m[`mbusw -1:1];
assign  s4_stb_o = i_bus_m[1] & i_bus_m[0] & i_ssel_dec[4];

// slave5

assign  {s5_adr_o, s5_sel_o, s5_dat_o, s5_we_o, s5_cab_o, s5_cyc_o} = i_bus_m[`mbusw -1:1];
assign  s5_stb_o = i_bus_m[1] & i_bus_m[0] & i_ssel_dec[5];

// slave6

assign  {s6_adr_o, s6_sel_o, s6_dat_o, s6_we_o, s6_cab_o, s6_cyc_o} = i_bus_m[`mbusw -1:1];
assign  s6_stb_o = i_bus_m[1] & i_bus_m[0] & i_ssel_dec[6];

// slave7

assign  {s7_adr_o, s7_sel_o, s7_dat_o, s7_we_o, s7_cab_o, s7_cyc_o} = i_bus_m[`mbusw -1:1];
assign  s7_stb_o = i_bus_m[1] & i_bus_m[0] & i_ssel_dec[7];

///////////////////////////////////////
//      Master and Slave input interface
//

`ifdef  WB_USE_TRISTATE
// input from master interface
assign  i_bus_m = i_gnt_arb[0] ? {m0_adr_i, m0_sel_i, m0_dat_i, m0_we_i, m0_cab_i, m0_cyc_i, m0_stb_i} : 72'bz ;
assign  i_bus_m = i_gnt_arb[1] ? {m1_adr_i, m1_sel_i, m1_dat_i, m1_we_i, m1_cab_i,m1_cyc_i, m1_stb_i} : 72'bz ;
assign  i_bus_m = i_gnt_arb[2] ? {m2_adr_i, m2_sel_i, m2_dat_i,  m2_we_i, m2_cab_i, m2_cyc_i, m2_stb_i} : 72'bz ;
assign  i_bus_m = i_gnt_arb[3] ? {m3_adr_i, m3_sel_i, m3_dat_i,  m3_we_i, m3_cab_i, m3_cyc_i, m3_stb_i} : 72'bz ;
assign  i_bus_m = i_gnt_arb[4] ? {m4_adr_i, m4_sel_i, m4_dat_i,  m4_we_i, m4_cab_i, m4_cyc_i, m4_stb_i} : 72'bz ;
assign  i_bus_m = i_gnt_arb[5] ? {m5_adr_i, m5_sel_i, m5_dat_i, m5_we_i, m5_cab_i, m5_cyc_i,  m5_stb_i} : 72'bz ;
assign  i_bus_m = i_gnt_arb[6] ? {m6_adr_i, m6_sel_i, m6_dat_i, m6_we_i, m6_cab_i, m6_cyc_i, m6_stb_i} : 72'bz ;
assign  i_bus_m = i_gnt_arb[7] ? {m7_adr_i, m7_sel_i, m7_dat_i, m7_we_i, m7_cab_i, m7_cyc_i,m7_stb_i} : 72'bz ;
// input from slave interface
assign  i_dat_s = i_ssel_dec[0] ? s0_dat_i: 32'bz;
assign  i_dat_s = i_ssel_dec[1] ? s1_dat_i: 32'bz;
assign  i_dat_s = i_ssel_dec[2] ? s2_dat_i: 32'bz;
assign  i_dat_s = i_ssel_dec[3] ? s3_dat_i: 32'bz;
assign  i_dat_s = i_ssel_dec[4] ? s4_dat_i: 32'bz;
assign  i_dat_s = i_ssel_dec[5] ? s5_dat_i: 32'bz;
assign  i_dat_s = i_ssel_dec[6] ? s6_dat_i: 32'bz;
assign  i_dat_s = i_ssel_dec[7] ? s7_dat_i: 32'bz;

`else

always @(gnt , m0_adr_i, m0_sel_i, m0_dat_i, m0_we_i, m0_cab_i, m0_cyc_i,m0_stb_i,
                m1_adr_i, m1_sel_i, m1_dat_i, m1_we_i, m1_cab_i, m1_cyc_i,m1_stb_i,
                m2_adr_i, m2_sel_i, m2_dat_i, m2_we_i, m2_cab_i, m2_cyc_i,m2_stb_i,
                m3_adr_i, m3_sel_i, m3_dat_i, m3_we_i, m3_cab_i, m3_cyc_i,m3_stb_i,
                m4_adr_i, m4_sel_i, m4_dat_i, m4_we_i, m4_cab_i, m4_cyc_i,m4_stb_i,
                m5_adr_i, m5_sel_i, m5_dat_i, m5_we_i, m5_cab_i, m5_cyc_i,m5_stb_i,
                m6_adr_i, m6_sel_i, m6_dat_i, m6_we_i, m6_cab_i, m6_cyc_i,m6_stb_i,
                m7_adr_i, m7_sel_i, m7_dat_i, m7_we_i, m7_cab_i, m7_cyc_i,m7_stb_i)
                case(gnt)
                        3'h0:   i_bus_m = {m0_adr_i, m0_sel_i, m0_dat_i, m0_we_i, m0_cab_i, m0_cyc_i,m0_stb_i};
                        3'h1:   i_bus_m = {m1_adr_i, m1_sel_i, m1_dat_i, m1_we_i, m1_cab_i, m1_cyc_i,m1_stb_i};
                        3'h2:   i_bus_m = {m2_adr_i, m2_sel_i, m2_dat_i, m2_we_i, m2_cab_i, m2_cyc_i,m2_stb_i};
                        3'h3:   i_bus_m = {m3_adr_i, m3_sel_i, m3_dat_i, m3_we_i, m3_cab_i, m3_cyc_i,m3_stb_i};
                        3'h4:   i_bus_m = {m4_adr_i, m4_sel_i, m4_dat_i, m4_we_i, m4_cab_i, m4_cyc_i,m4_stb_i};
                        3'h5:   i_bus_m = {m5_adr_i, m5_sel_i, m5_dat_i, m5_we_i, m5_cab_i, m5_cyc_i,m5_stb_i};
                        3'h6:   i_bus_m = {m6_adr_i, m6_sel_i, m6_dat_i, m6_we_i, m6_cab_i, m6_cyc_i,m6_stb_i};
                        3'h7:   i_bus_m = {m7_adr_i, m7_sel_i, m7_dat_i, m7_we_i, m7_cab_i, m7_cyc_i,m7_stb_i};
                        default:i_bus_m =  72'b0;//{m0_adr_i, m0_sel_i, m0_dat_i, m0_we_i, m0_cab_i, m0_cyc_i,m0_stb_i};
endcase                 

assign  i_dat_s = i_ssel_dec[0] ? s0_dat_i :
                                  i_ssel_dec[1] ? s1_dat_i :
                                  i_ssel_dec[2] ? s2_dat_i :
                                  i_ssel_dec[3] ? s3_dat_i :
                                  i_ssel_dec[4] ? s4_dat_i :
                                  i_ssel_dec[5] ? s5_dat_i :
                                  i_ssel_dec[6] ? s6_dat_i :
                                  i_ssel_dec[7] ? s7_dat_i : {`dw{1'b0}}; 
`endif
//
// arbitor 
//
assign i_gnt_arb[0] = (gnt == 3'd0);
assign i_gnt_arb[1] = (gnt == 3'd1);
assign i_gnt_arb[2] = (gnt == 3'd2);
assign i_gnt_arb[3] = (gnt == 3'd3);
assign i_gnt_arb[4] = (gnt == 3'd4);
assign i_gnt_arb[5] = (gnt == 3'd5);
assign i_gnt_arb[6] = (gnt == 3'd6);
assign i_gnt_arb[7] = (gnt == 3'd7);

wb_conbus_arb   wb_conbus_arb(
        .clk(clk_i), 
        .rst(rst_i),
        .req({  m7_cyc_i,
                m6_cyc_i,
                m5_cyc_i,
                m4_cyc_i,
                m3_cyc_i,
                m2_cyc_i,
                m1_cyc_i,
                m0_cyc_i}),
        .gnt(gnt)
);

//////////////////////////////////
//              address decode logic
//
wire [7:0]      m0_ssel_dec, m1_ssel_dec, m2_ssel_dec, m3_ssel_dec, m4_ssel_dec, m5_ssel_dec, m6_ssel_dec, m7_ssel_dec;
always @(gnt, m0_ssel_dec, m1_ssel_dec, m2_ssel_dec, m3_ssel_dec, m4_ssel_dec, m5_ssel_dec, m6_ssel_dec, m7_ssel_dec)
        case(gnt)
                3'h0: i_ssel_dec = m0_ssel_dec;
                3'h1: i_ssel_dec = m1_ssel_dec;
                3'h2: i_ssel_dec = m2_ssel_dec;
                3'h3: i_ssel_dec = m3_ssel_dec;
                3'h4: i_ssel_dec = m4_ssel_dec;
                3'h5: i_ssel_dec = m5_ssel_dec;
                3'h6: i_ssel_dec = m6_ssel_dec;
                3'h7: i_ssel_dec = m7_ssel_dec;
                default: i_ssel_dec = 7'b0;
endcase
//
//      decode all master address before arbitor for running faster
//      
assign m0_ssel_dec[0] = (m0_adr_i[`aw -1 : `aw - s0_addr_w ] == s0_addr);
assign m0_ssel_dec[1] = (m0_adr_i[`aw -1 : `aw - s1_addr_w ] == s1_addr);
assign m0_ssel_dec[2] = (m0_adr_i[`aw -1 : `aw - s2_addr_w ] == s2_addr);
assign m0_ssel_dec[3] = (m0_adr_i[`aw -1 : `aw - s3_addr_w ] == s3_addr);
assign m0_ssel_dec[4] = (m0_adr_i[`aw -1 : `aw - s4_addr_w ] == s4_addr);
assign m0_ssel_dec[5] = (m0_adr_i[`aw -1 : `aw - s5_addr_w ] == s5_addr);
assign m0_ssel_dec[6] = (m0_adr_i[`aw -1 : `aw - s6_addr_w ] == s6_addr);
assign m0_ssel_dec[7] = (m0_adr_i[`aw -1 : `aw - s7_addr_w ] == s7_addr);

assign m1_ssel_dec[0] = (m1_adr_i[`aw -1 : `aw - s0_addr_w ] == s0_addr);
assign m1_ssel_dec[1] = (m1_adr_i[`aw -1 : `aw - s1_addr_w ] == s1_addr);
assign m1_ssel_dec[2] = (m1_adr_i[`aw -1 : `aw - s2_addr_w ] == s2_addr);
assign m1_ssel_dec[3] = (m1_adr_i[`aw -1 : `aw - s3_addr_w ] == s3_addr);
assign m1_ssel_dec[4] = (m1_adr_i[`aw -1 : `aw - s4_addr_w ] == s4_addr);
assign m1_ssel_dec[5] = (m1_adr_i[`aw -1 : `aw - s5_addr_w ] == s5_addr);
assign m1_ssel_dec[6] = (m1_adr_i[`aw -1 : `aw - s6_addr_w ] == s6_addr);
assign m1_ssel_dec[7] = (m1_adr_i[`aw -1 : `aw - s7_addr_w ] == s7_addr);

assign m2_ssel_dec[0] = (m2_adr_i[`aw -1 : `aw - s0_addr_w ] == s0_addr);
assign m2_ssel_dec[1] = (m2_adr_i[`aw -1 : `aw - s1_addr_w ] == s1_addr);
assign m2_ssel_dec[2] = (m2_adr_i[`aw -1 : `aw - s2_addr_w ] == s2_addr);
assign m2_ssel_dec[3] = (m2_adr_i[`aw -1 : `aw - s3_addr_w ] == s3_addr);
assign m2_ssel_dec[4] = (m2_adr_i[`aw -1 : `aw - s4_addr_w ] == s4_addr);
assign m2_ssel_dec[5] = (m2_adr_i[`aw -1 : `aw - s5_addr_w ] == s5_addr);
assign m2_ssel_dec[6] = (m2_adr_i[`aw -1 : `aw - s6_addr_w ] == s6_addr);
assign m2_ssel_dec[7] = (m2_adr_i[`aw -1 : `aw - s7_addr_w ] == s7_addr);

assign m3_ssel_dec[0] = (m3_adr_i[`aw -1 : `aw - s0_addr_w ] == s0_addr);
assign m3_ssel_dec[1] = (m3_adr_i[`aw -1 : `aw - s1_addr_w ] == s1_addr);
assign m3_ssel_dec[2] = (m3_adr_i[`aw -1 : `aw - s2_addr_w ] == s2_addr);
assign m3_ssel_dec[3] = (m3_adr_i[`aw -1 : `aw - s3_addr_w ] == s3_addr);
assign m3_ssel_dec[4] = (m3_adr_i[`aw -1 : `aw - s4_addr_w ] == s4_addr);
assign m3_ssel_dec[5] = (m3_adr_i[`aw -1 : `aw - s5_addr_w ] == s5_addr);
assign m3_ssel_dec[6] = (m3_adr_i[`aw -1 : `aw - s6_addr_w ] == s6_addr);
assign m3_ssel_dec[7] = (m3_adr_i[`aw -1 : `aw - s7_addr_w ] == s7_addr);

assign m4_ssel_dec[0] = (m4_adr_i[`aw -1 : `aw - s0_addr_w ] == s0_addr);
assign m4_ssel_dec[1] = (m4_adr_i[`aw -1 : `aw - s1_addr_w ] == s1_addr);
assign m4_ssel_dec[2] = (m4_adr_i[`aw -1 : `aw - s2_addr_w ] == s2_addr);
assign m4_ssel_dec[3] = (m4_adr_i[`aw -1 : `aw - s3_addr_w ] == s3_addr);
assign m4_ssel_dec[4] = (m4_adr_i[`aw -1 : `aw - s4_addr_w ] == s4_addr);
assign m4_ssel_dec[5] = (m4_adr_i[`aw -1 : `aw - s5_addr_w ] == s5_addr);
assign m4_ssel_dec[6] = (m4_adr_i[`aw -1 : `aw - s6_addr_w ] == s6_addr);
assign m4_ssel_dec[7] = (m4_adr_i[`aw -1 : `aw - s7_addr_w ] == s7_addr);

assign m5_ssel_dec[0] = (m5_adr_i[`aw -1 : `aw - s0_addr_w ] == s0_addr);
assign m5_ssel_dec[1] = (m5_adr_i[`aw -1 : `aw - s1_addr_w ] == s1_addr);
assign m5_ssel_dec[2] = (m5_adr_i[`aw -1 : `aw - s2_addr_w ] == s2_addr);
assign m5_ssel_dec[3] = (m5_adr_i[`aw -1 : `aw - s3_addr_w ] == s3_addr);
assign m5_ssel_dec[4] = (m5_adr_i[`aw -1 : `aw - s4_addr_w ] == s4_addr);
assign m5_ssel_dec[5] = (m5_adr_i[`aw -1 : `aw - s5_addr_w ] == s5_addr);
assign m5_ssel_dec[6] = (m5_adr_i[`aw -1 : `aw - s6_addr_w ] == s6_addr);
assign m5_ssel_dec[7] = (m5_adr_i[`aw -1 : `aw - s7_addr_w ] == s7_addr);

assign m6_ssel_dec[0] = (m6_adr_i[`aw -1 : `aw - s0_addr_w ] == s0_addr);
assign m6_ssel_dec[1] = (m6_adr_i[`aw -1 : `aw - s1_addr_w ] == s1_addr);
assign m6_ssel_dec[2] = (m6_adr_i[`aw -1 : `aw - s2_addr_w ] == s2_addr);
assign m6_ssel_dec[3] = (m6_adr_i[`aw -1 : `aw - s3_addr_w ] == s3_addr);
assign m6_ssel_dec[4] = (m6_adr_i[`aw -1 : `aw - s4_addr_w ] == s4_addr);
assign m6_ssel_dec[5] = (m6_adr_i[`aw -1 : `aw - s5_addr_w ] == s5_addr);
assign m6_ssel_dec[6] = (m6_adr_i[`aw -1 : `aw - s6_addr_w ] == s6_addr);
assign m6_ssel_dec[7] = (m6_adr_i[`aw -1 : `aw - s7_addr_w ] == s7_addr);

assign m7_ssel_dec[0] = (m7_adr_i[`aw -1 : `aw - s0_addr_w ] == s0_addr);
assign m7_ssel_dec[1] = (m7_adr_i[`aw -1 : `aw - s1_addr_w ] == s1_addr);
assign m7_ssel_dec[2] = (m7_adr_i[`aw -1 : `aw - s2_addr_w ] == s2_addr);
assign m7_ssel_dec[3] = (m7_adr_i[`aw -1 : `aw - s3_addr_w ] == s3_addr);
assign m7_ssel_dec[4] = (m7_adr_i[`aw -1 : `aw - s4_addr_w ] == s4_addr);
assign m7_ssel_dec[5] = (m7_adr_i[`aw -1 : `aw - s5_addr_w ] == s5_addr);
assign m7_ssel_dec[6] = (m7_adr_i[`aw -1 : `aw - s6_addr_w ] == s6_addr);
assign m7_ssel_dec[7] = (m7_adr_i[`aw -1 : `aw - s7_addr_w ] == s7_addr);

//assign i_ssel_dec[0] = (i_bus_m[`mbusw -1 : `mbusw - s0_addr_w ] == s0_addr);
//assign i_ssel_dec[1] = (i_bus_m[`mbusw -1 : `mbusw - s1_addr_w ] == s1_addr);
//assign i_ssel_dec[2] = (i_bus_m[`mbusw -1 : `mbusw - s27_addr_w ] == s2_addr);
//assign i_ssel_dec[3] = (i_bus_m[`mbusw -1 : `mbusw - s27_addr_w ] == s3_addr);
//assign i_ssel_dec[4] = (i_bus_m[`mbusw -1 : `mbusw - s27_addr_w ] == s4_addr);
//assign i_ssel_dec[5] = (i_bus_m[`mbusw -1 : `mbusw - s27_addr_w ] == s5_addr);
//assign i_ssel_dec[6] = (i_bus_m[`mbusw -1 : `mbusw - s27_addr_w ] == s6_addr);
//assign i_ssel_dec[7] = (i_bus_m[`mbusw -1 : `mbusw - s27_addr_w ] == s7_addr);


endmodule