Subversion Repositories theia_gpu

`timescale 1ns / 1ps

`include "aDefinitions.v"

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

Theia, Ray Cast Programable graphic Processing Unit.

Copyright (C) 2010  Diego Valverde (diego.valverde.g@gmail.com)

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; either version 2

of the License, or (at your option) any later version.

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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

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

//---------------------------------------------------------------------------

module THEIA

(

input wire                    CLK_I,    //Input clock

input wire                    RST_I,    //Input reset

//Theia Interfaces

input wire                    MST_I,    //Master signal, THEIA enters configuration mode

                                       //when this gets asserted (see documentation)

//Wish Bone Interface

input wire [`WB_WIDTH-1:0]    DAT_I,     //Input data bus  (Wishbone)

input wire                    ACK_I,    //Input ack

output wire                   ACK_O,    //Output ack

input wire [`WB_WIDTH-1:0]    ADR_I,     //Input address

input wire                    WE_I,    //Input write enable

input wire                    STB_I,    //Strobe signal, see wishbone documentation

input wire                    CYC_I,   //Bus cycle signal, see wishbone documentation

input wire [1:0]              TGA_I,   //Input address tag, see THEAI documentation

input wire [`MAX_CORES-1:0]      SEL_I,  //The WishBone Master uses this signal to configure a specific core (TBD, not sure is needed)

input wire [`MAX_CORES-1:0]   RENDREN_I,

input wire [`MAX_CORE_BITS-1:0]      OMBSEL_I,  //Output memory bank select

input wire [`WB_WIDTH-1:0]           OMADR_I,  //Output adress (relative to current bank)

output wire [`WB_WIDTH-1:0]          OMEM_O,      //Output data bus (Wishbone)

input wire [`WB_WIDTH-1:0]           TMDAT_I,

input wire [`WB_WIDTH-1:0]           TMADR_I,

input wire                           TMWE_I,

input wire [`MAX_TMEM_BANKS-1:0]     TMSEL_I,

//Control Register

input wire [15:0]                         CREG_I,

output wire                   GRDY_O,

input wire                    STDONE_I,

input wire                    HDA_I,

input wire                    GACK_I,

output wire                   RCOMMIT_O,

output wire                   DONE_O

);

wire [`MAX_TMEM_BANKS-1:0] wTMemWriteEnable;

SELECT_1_TO_N # ( `MAX_TMEM_BANKS, `MAX_TMEM_BANKS ) TMWE_SEL

                        (

                        .Sel(TMSEL_I),

                        .En(TMWE_I),

                        .O(wTMemWriteEnable)

                        );

wire [`MAX_CORES-1:0] wDone;

wire [`MAX_CORES-1:0] wBusGranted,wBusRequest;

//wire [`WB_WIDTH-1:0]  wDAT_O[`MAX_CORES-1:0];

//wire [`WB_WIDTH-1:0]  wADR_O[`MAX_CORES-1:0];

//wire [1:0] wTGA_O[`MAX_CORES-1:0];

wire [`MAX_CORE_BITS-1:0] wBusSelect;

//wire [`MAX_CORES-1:0] wSTB_O;

//wire [`MAX_CORES-1:0] wWE_O;

wire [`MAX_CORES-1:0]wACK_O;

wire wOMem_WE[`MAX_CORES-1:0];

wire [`WB_WIDTH-1:0] wOMEM_Address[`MAX_CORES-1:0];

wire [`WB_WIDTH-1:0] wOMEM_Dat[`MAX_CORES-1:0];

wire [`MAX_CORES-1:0]   wSTB_I;

wire [`MAX_CORES-1:0]   wMST_I;

wire [`MAX_CORES-1:0]   wACK_I;

wire [`MAX_CORES-1:0]   wCYC_I;

wire [1:0]              wTGA_I[`MAX_CORES-1:0];

wire [`WB_WIDTH-1:0]  wTMEM_Data;

wire [`WB_WIDTH-1:0]  wTMEM_Address[`MAX_CORES-1:0];

wire [`WB_WIDTH-1:0]  wTMEM_ReadAddr;

wire [`MAX_CORES-1:0] wTMEM_Resquest;

wire [`MAX_CORES-1:0] wTMEM_Granted;

//CROSS-BAR cables

wire [`WB_WIDTH-1:0]     wCrossBarDataRow[`MAX_TMEM_BANKS-1:0];                   //Horizontal grid Buses comming from each bank 

wire [`WB_WIDTH-1:0]     wCrossBarDataCollumn[`MAX_CORES-1:0];          //Vertical grid buses comming from each core.

wire [`WB_WIDTH-1:0]     wTMemReadAdr[`MAX_CORES-1:0];                                       //Horizontal grid Buses comming from each core (virtual addr).

wire [`WB_WIDTH-1:0]     wCrossBarAdressCollumn[`MAX_CORES-1:0];                  //Vertical grid buses comming from each core. (physical addr).

wire [`WB_WIDTH-1:0]     wCrossBarAddressRow[`MAX_TMEM_BANKS-1:0];                //Horizontal grid Buses comming from each bank.

wire                                                wCORE_2_TMEM__Req[`MAX_CORES-1:0];

wire [`MAX_TMEM_BANKS -1:0]    wBankReadRequest[`MAX_CORES-1:0];

wire [`MAX_CORES-1:0]         wBankReadGranted[`MAX_TMEM_BANKS-1:0];

wire                           wTMEM_2_Core__Grant[`MAX_CORES-1:0];

wire[`MAX_CORE_BITS-1:0] wCurrentCoreSelected[`MAX_TMEM_BANKS-1:0];

wire[7:0]                wCoreBankSelect[`MAX_CORES-1:0];

wire [`MAX_CORES-1:0] wGRDY_O;

wire [`MAX_CORES-1:0] wGReady;

wire [`MAX_CORES-1:0] wRCOMMIT_O;

wire [`MAX_CORES-1:0] wRCommited;

assign RCOMMIT_O = wRCommited[0] & wRCommited[1] & wRCommited[2] & wRCommited[3] & wRCommited[4] & wRCommited[5] & wRCommited[6] & wRCommited[7];

assign GRDY_O = wGReady[0] & wGReady[1] & wGReady[2] & wGReady[3] & wGReady[4] & wGReady[5] & wGReady[6] & wGReady[7];

//----------------------------------------------------------------      

//The next secuencial logic just AND all the wDone signals

//I know that it would be much more elgant to just do parallel:

//assign DONE_O = wDone[0] & wDone[1] & ... & wDone[MAX_CORES-1];

//However, I don't know how to achieve this with 'generate' statements

//So coding a simple loop instead

/*

always @ (posedge CLK_I)

begin : AND_DONE_SIGNALS

  integer k;

  DONE_O = wDone[0];

  for (k=0;k<=`MAX_CORES;k=k+1)

    DONE_O=DONE_O & wDone[k+1];

end

*/

assign DONE_O = wDone[0] & wDone[1] & wDone[2] & wDone[3] & wDone[4] & wDone[5] & wDone[6] & wDone[7];   //Replace this by a counter??

//----------------------------------------------------------------      

        Module_BusArbitrer ARB1

        (

        .Clock( CLK_I ),

        .Reset( RST_I ),

        .iRequest( wBusRequest ),

        .oGrant(   wBusGranted ),

        .oBusSelect( wBusSelect )

        );

//----------------------------------------------------------------

  assign ACK_O = wACK_O[ wBusSelect];

 wire [`WB_WIDTH-1:0] wDataOut[`MAX_CORES-1:0];

 assign OMEM_O = wDataOut[ OMBSEL_I ];

  genvar i;

  generate

        for (i = 0; i < `MAX_CORES; i = i +1)

        begin : CORE

                assign wMST_I[i] = (SEL_I[i]) ? MST_I : 0;

                assign wSTB_I[i] = (SEL_I[i]) ? STB_I : 0;

                assign wCYC_I[i] = (SEL_I[i]) ? CYC_I : 0;

                assign wTGA_I[i] = (SEL_I[i]) ? TGA_I : 0;

                THEIACORE CTHEIA

                (

                .CLK_I( CLK_I ),

                .RST_I( RST_I ),

                .RENDREN_I( RENDREN_I[i] ),

                //Slave signals

                .ADR_I( ADR_I ),

                .WE_I(  WE_I  ),

                .STB_I(  wSTB_I[i] ),

                .ACK_I( ACK_I ),

                .CYC_I( wCYC_I[i] ),

                .MST_I( wMST_I[i] ),

                .TGA_I( wTGA_I[i] ),

                .CREG_I( CREG_I ),

                //Master Signals

                .ACK_O(         wACK_O[i] ),

                .CYC_O(  wBusRequest[i] ),

                .GNT_I(         wBusGranted[i] ),

                `ifdef DEBUG

                .iDebug_CoreID( i ),

                `endif

                .OMEM_WE_O( wOMem_WE[i] ),

                .OMEM_ADR_O( wOMEM_Address[i] ),

                .OMEM_DAT_O( wOMEM_Dat[i] ),

                .TMEM_DAT_I( wCrossBarDataCollumn[i]    ),

                .TMEM_ADR_O( wTMemReadAdr[i]  ),

                .TMEM_CYC_O( wCORE_2_TMEM__Req[i]       ),

                .TMEM_GNT_I( wTMEM_2_Core__Grant[i]     ),

                .GRDY_O( wGRDY_O[i] ),

                .STDONE_I( STDONE_I ),

                .RCOMMIT_O( wRCOMMIT_O[i] ),

                .HDA_I(     HDA_I ),

                //Other

                .DAT_I( DAT_I ),

                .DONE_O( wDone[i] )

        );

        UPCOUNTER_POSEDGE # (1) UP_RCOMMIT

        (

        .Clock(  CLK_I ),

        .Reset( RST_I | GACK_I ),

        .Initial( 1'b0 ),

        .Enable( wRCOMMIT_O[i] ),

        .Q(wRCommited[i])

        );

        UPCOUNTER_POSEDGE # (1) UP_GREADY

        (

        .Clock(  CLK_I ),

        .Reset( RST_I | GACK_I ),

        .Initial( 1'b0 ),

        .Enable( wGRDY_O[i] ),

        .Q(wGReady[i])

        );

        RAM_SINGLE_READ_PORT # ( `WB_WIDTH, `WB_WIDTH, 250000 ) OMEM //500000 ) OMEM 

(

        .Clock(         CLK_I                ),

        .iWriteEnable(  wOMem_WE[i]          ),

        .iWriteAddress( wOMEM_Address[i]     ),

        .iDataIn(       wOMEM_Dat[i]         ),

        .iReadAddress0( OMADR_I              ),

        .oDataOut0(     wDataOut[i]          )

);

//If there are "n" banks, memory location "X" would reside in bank number X mod n.

//X mod 2^n == X & (2^n - 1)

assign wCoreBankSelect[i] = (wTMemReadAdr[i] & (`MAX_TMEM_BANKS-1));

//Each core has 1 bank request slot

//Each slot has MAX_TMEM_BANKS bits. Only 1 bit can

//be 1 at any given point in time. All bits zero means,

//we are not requesting to read from any memory bank.

SELECT_1_TO_N # ( `MAX_TMEM_BANKS, `MAX_CORES ) READDRQ

                        (

                        .Sel(wCoreBankSelect[ i]),

                        .En(wCORE_2_TMEM__Req[i]),

                        .O(wBankReadRequest[i])

                        );

//The address coming from the core is  virtual adress, meaning it assumes linear

//address space, however, since memory is interleaved in a n-way memory we transform

//virtual adress into physical adress (relative to the bank) like this

//fadr = vadr / n = vadr >> log2(n)

assign wCrossBarAdressCollumn[i] = (wTMemReadAdr[i] >> `MAX_CORE_BITS);

//Connect the granted signal to Arbiter of the Bank we want to read from        

assign wTMEM_2_Core__Grant[i] = wBankReadGranted[wCoreBankSelect[i]][i];

//Connect the request signal to Arbiter of the Bank we want to read from        

//assign wBankReadRequest[wCoreBankSelect[i]][i] = wCORE_2_TMEM__Req[i];

        end

  endgenerate

////////////// CROSS-BAR INTERCONECTION//////////////////////////

genvar Core,Bank;

generate

for (Bank = 0; Bank < `MAX_TMEM_BANKS; Bank = Bank + 1)

begin : BANK

        //The memory bank itself

RAM_SINGLE_READ_PORT     # ( `WB_WIDTH, `WB_WIDTH, 50000 ) TMEM

        (

        .Clock(         CLK_I                                   ),

        .iWriteEnable(  wTMemWriteEnable[Bank]       ),

        .iWriteAddress( TMADR_I                      ),

        .iDataIn(       TMDAT_I                      ),

        .iReadAddress0( wCrossBarAddressRow[Bank]    ), //Connect to the Row of the grid

        .oDataOut0(     wCrossBarDataRow[Bank]                  )  //Connect to the Row of the grid

        );

        //Arbiter will Round-Robin Cores attempting to read from the same Bank

        //at a given point in time

wire [`MAX_CORES-1:0]         wBankReadGrantedDelay[`MAX_TMEM_BANKS-1:0];

        Module_BusArbitrer ARB_TMEM

        (

        .Clock( CLK_I ),

        .Reset( RST_I ),

        .iRequest( {wBankReadRequest[7][Bank],wBankReadRequest[6][Bank],wBankReadRequest[5][Bank],wBankReadRequest[4][Bank],wBankReadRequest[3][Bank],wBankReadRequest[2][Bank],wBankReadRequest[1][Bank],wBankReadRequest[0][Bank]}),//wBankReadRequest[Bank] ),   //The cores requesting to read from this Bank

        .oGrant(   wBankReadGrantedDelay[Bank]  ),  //The bit of the core granted to read from this Bank

        .oBusSelect( wCurrentCoreSelected[Bank] )                       //The index of the core granted to read from this Bank

        );

        FFD_POSEDGE_SYNCRONOUS_RESET # ( `MAX_CORES ) FFD_GNT

(

        .Clock(CLK_I),

        .Reset(RST_I),

        .Enable( 1'b1 ),

        .D(wBankReadGrantedDelay[Bank]),

        .Q(wBankReadGranted[Bank])

);

        //Create the Cross-Bar interconnection grid now, rows are coonected to the memory banks,

        //while collumns are connected to the cores, 2 or more cores can not read from the same

        //bank at any given point in time

        for (Core = 0; Core < `MAX_CORES; Core = Core + 1)

        begin: CORE_CONNECT

                //Connect the Data Collum of this core to the Data Row of current bank, only if the Core is looking for data stored in this bank

                assign wCrossBarDataCollumn[ Core ] = ( wCoreBankSelect[ Core ] == Bank ) ? wCrossBarDataRow[ Bank ] : `WB_WIDTH'bz;

                //Connect the Address Row of this Bank to the Address Column of the core, only if the Arbiter selected this core for reading

                assign wCrossBarAddressRow[ Bank ] = ( wCurrentCoreSelected[ Bank ] == Core ) ? wCrossBarAdressCollumn[Core]: `WB_WIDTH'bz;

        end

end

endgenerate

////////////// CROSS-BAR INTERCONECTION//////////////////////////

//----------------------------------------------------------------

endmodule

//---------------------------------------------------------------------------