Subversion Repositories an-fpga-implementation-of-low-latency-noc-based-mpsoc

`timescale     1ns/1ps

/**********************************************************************

**      File: crossbar.v

**

**      Copyright (C) 2014-2017  Alireza Monemi

**

**      This file is part of ProNoC

**

**      ProNoC ( stands for Prototype Network-on-chip)  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 of the License, or (at your option) any later version.

**

**      ProNoC 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 ProNoC. If not, see <http:**www.gnu.org/licenses/>.

**

**

**      Description:

**      NoC router crosbar module

**

**************************************************************/

module crossbar #(

    parameter NOC_ID=0,

    parameter TOPOLOGY = "MESH",

    parameter V    = 4,     // vc_num_per_port

    parameter P    = 5,     // router port num

    parameter Fw     = 36,

    parameter MUX_TYPE="BINARY",        //"ONE_HOT" or "BINARY"    

    parameter SSA_EN="YES", // "YES" , "NO"

    parameter SELF_LOOP_EN= "NO"

)

(

    granted_dest_port_all,

    flit_in_all,

    flit_out_all,

    flit_out_wr_all,

    ssa_flit_wr_all

 );

    function integer log2;

      input integer number; begin

         log2=(number <=1) ? 1: 0;

         while(2**log2<number) begin

            log2=log2+1;

         end

      end

    endfunction // log2 

    localparam

        PV = V * P,

        VV = V * V,

        PP = P * P,

        PVV = PV * V,

        P_1 = (SELF_LOOP_EN == "NO")? P-1 : P,

        VP_1 = V * P_1,

        PP_1 = P_1 * P,

        PVP_1 = PV * P_1,

        PFw = P*Fw,

        P_1Fw = P_1 * Fw,

        P_1w = log2(P_1);

    input [PP_1-1 : 0] granted_dest_port_all;

    input [PFw-1 : 0] flit_in_all;

    output [PFw-1 : 0] flit_out_all;

    output [P-1 : 0] flit_out_wr_all;

    input  [P-1 : 0] ssa_flit_wr_all;

    wire [P-1 : 0]  flit_we_mux_out;

    wire [P_1-1 : 0] granted_dest_port [P-1 : 0];

    wire [P_1Fw-1 : 0] mux_in [P-1 : 0];

    wire [P_1-1 : 0] mux_sel_pre [P-1 : 0];

    wire [P_1-1 : 0]  mux_sel [P-1 : 0];

    wire [P_1w-1 : 0] mux_sel_bin [P-1 : 0];

    wire [PP-1 : 0] flit_out_wr_gen;

    genvar i,j;

    generate

    for(i=0;i<P;i=i+1)begin : port_loop

        assign granted_dest_port[i] = granted_dest_port_all[(i+1)*P_1-1 : i*P_1];

        for(j=0;j<P;j=j+1)begin : port_loop2

            if(SELF_LOOP_EN == "NO") begin : nslp

                //remove sender port flit from flit list

                if(i>j)    begin :if1

                    assign mux_in[i][(j+1)*Fw-1 : j*Fw]=     flit_in_all[(j+1)*Fw-1 : j*Fw];

                    assign mux_sel_pre[i][j] =    granted_dest_port[j][i-1];

                end

                else if(i<j) begin :if2

                    assign mux_in[i][j*Fw-1 : (j-1)*Fw]=     flit_in_all[(j+1)*Fw-1 : j*Fw];

                    assign mux_sel_pre[i][j-1] =    granted_dest_port[j][i];

                end

            end else begin : slp

                assign mux_in[i][(j+1)*Fw-1 : j*Fw]=     flit_in_all[(j+1)*Fw-1 : j*Fw];

                assign mux_sel_pre[i][j] =    granted_dest_port[j][i];

            end

        end//for j

        /* verilator lint_off WIDTH */

        if (SSA_EN =="YES")begin :predict //If no output is granted replace the output port with SS port

        /* verilator lint_on WIDTH */

            add_ss_port #(

                .NOC_ID(NOC_ID),

                .SW_LOC(i),

                    .P(P)

            )

            ss_port

            (

                .destport_in (mux_sel_pre[i]),

                .destport_out(mux_sel [i])

            );

        end else begin :nopredict

               assign mux_sel[i]= mux_sel_pre[i];

        end

        /* verilator lint_off WIDTH */

        if    (MUX_TYPE    ==    "ONE_HOT") begin : one_hot_gen

        /* verilator lint_on WIDTH */

            onehot_mux_1D #(

                .W (Fw),

                .N (P_1)

            )

            cross_mux

            (

                .in (mux_in [i]),

                .out (flit_out_all[(i+1)*Fw-1 : i*Fw]),

                .sel (mux_sel[i])

            );

        end else begin : binary

            one_hot_to_bin #(

                .ONE_HOT_WIDTH(P_1),

                .BIN_WIDTH(P_1w)

            )

            conv

            (

                .one_hot_code(mux_sel[i]),

                .bin_code(mux_sel_bin[i])

            );

            binary_mux #(

                .IN_WIDTH(P_1Fw),

                .OUT_WIDTH(Fw)

            )

            cross_mux

            (

                .mux_in(mux_in [i]),

                .mux_out(flit_out_all[(i+1)*Fw-1 : i*Fw]),

                .sel(mux_sel_bin[i])

            );

        end//binary

        if(SELF_LOOP_EN == "NO") begin : nslp

            add_sw_loc_one_hot #(

                .P(P),

                .SW_LOC(i)

            )

            add_sw_loc

            (

                .destport_in(granted_dest_port_all[(i+1)*P_1-1 : i*P_1]),

                .destport_out(flit_out_wr_gen [(i+1)*P-1 : i*P])

            );

        end else begin :slp

            assign flit_out_wr_gen [(i+1)*P-1 : i*P] = granted_dest_port_all[(i+1)*P_1-1 : i*P_1];

        end

    end//for i    

    endgenerate

    custom_or #(

        .IN_NUM(P),

        .OUT_WIDTH(P)

    )

    wide_or

    (

        .or_in(flit_out_wr_gen),

        .or_out(flit_we_mux_out)

    );

    assign    flit_out_wr_all = flit_we_mux_out | ssa_flit_wr_all;

endmodule