Subversion Repositories theia_gpu

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

Theaia, Ray Cast Programable graphic Processing Unit.

Copyright (C) 2009  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 Description:

The scene geomtry is assumed to be grouped in a balance tree, specifically a

OCT tree.

Geometry unit is responsible for traversing this tree and requesting the geoemtry

primitives accordingly.

The root of the tree has global information on the scene, and each node

can have up to 8 child nodes. Leafs can have geometry on it or not depending on the

tree generation algorith.

In the scenario where AABBIU is not used, the tree has a single node and a single leaf,

which is the the root of the tree.

The geomrty unit groups a series of modules that are in charge of fetching

the various types of geometry. Depending on weather you are using AABBIU or not

and wether you have texturing enabled or not, the way in which the primitives

and data structures are requested varies.

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

`timescale 1ns / 1ps

`include "aDefinitions.v"

`define GFSM_SELECT_TFU 2'b00  //Triangle Fetch

`define GFSM_SELECT_TFF 2'b01  //Texture Fetch

`define GFSM_SELECT_TNF 2'b10  //Tree node fetch

`define GFSM_SELECT_NULL 2'b11

module GeometryUnit

(

        input  wire                           Clock,

        input  wire                           Reset,

        input  wire                           iEnable,

        input wire                            iTexturingEnable,

        input   wire [`WIDTH-1:0]               iData_WBM,

        input wire                            iDataReady_WBM,

        output wire [`WIDTH-1:0]              oAddressWBM_Imm,

        output wire                           oAddressWBM_IsImm,

        output wire [`DATA_ADDRESS_WIDTH-1:0] oAddressWBM_fromMEM,

        output wire                           oEnable_WBM,

        output wire                           oSetAddressWBM,

        output wire                           oRequest_AABBIU,

        output wire                           oRequest_BIU,

        output wire                           oRequest_TCC,

        output wire[`DATA_ADDRESS_WIDTH-1:0]  oRAMWriteAddress,

        output wire                           oRAMWriteEnable,

        input wire                            iMicrocodeExecutionDone,

        input wire                            iMicroCodeReturnValue,

        output wire                           oRequestingTextures,

        input wire                            iTrigger_TFF,

        input wire                            iBIUHit,

        output wire                           oTFFDone,

        output wire                           oSync,

        output wire                           oSetIOWriteBackAddr,

        output wire                           oDone

);

        //Unit interconnections 

        wire wTrigger_TNF;                                 //Trigger Tree Node Fetch Unit.      GSFM -> TNF

        wire wTrigger_TFU;                                 //Trigger Data Fetch Unit.                   GFSM -> TFU     

        //wire wTrigger_TFF;                                                                                    //Trigger testure Fetch Unit.           GFSM -> TFF     

        wire [`WIDTH-1:0] wNodeAddress;                    //Address of the current Node.        GFSM -> TNF

        wire [`WIDTH-1:0] wTNF2_TFU__TriangleDataOffset;   //Offset of the vertex Data.          TNF  -> GFSM

        wire [`WIDTH-1:0] wNode_TriangleCount;             //Number of traingles in this node. TNF -> GFSM

        wire [`WIDTH-1:0] wNode_Brother_Address;           //Address of the currents Node Brother. TNF -> GFSM

        wire [`WIDTH-1:0] wParents_Brother_Address;        //Address of the Brother of current node's parent. TNF -> GFSM

        wire [`WIDTH-1:0] wAddress_TFU;

        //wire [`DATA_ADDRESS_WIDTH-1:0] wAddress_TFF;

        wire [`WIDTH-1:0] wAddress_TNF;

        wire [`DATA_ADDRESS_WIDTH-1:0] wRAMWriteAddress_TFU;

        wire [`DATA_ADDRESS_WIDTH-1:0] wRAMWriteAddress_TFF;

        wire [`DATA_ADDRESS_WIDTH-1:0] wRAMWriteAddress_TNF;

        wire [1:0] wWBM_Address_Selector;

        wire wTFN_Enable_WBM,wNode_IsLeaf;

        wire wTNF2__SetAddressWBM, wTFU2__SetAddressWBM,wTFF2__SetAddressWBM;

        wire wRAMWriteEnable_TFF;

        wire wNodeReadDone,wRAMWriteEnable_TNF,wTriangleReadDone,wTextureFetchDone;

        wire wTFU_Trigger_WBM,wTFF_Trigger_WBM,wRAMWriteEnable_TFU;

        wire wGFSM2_TFU__SetAddressOffset;

assign oEnable_WBM = wTFN_Enable_WBM ^ wTFU_Trigger_WBM ^ wTFF_Trigger_WBM; //XXX TODO: Wath out!

assign oRequestingTextures = (wWBM_Address_Selector == `GFSM_SELECT_TFF ) ? 1 : 0;

assign oAddressWBM_Imm = ( wWBM_Address_Selector == `GFSM_SELECT_TFU ) ? wAddress_TFU : wAddress_TNF;

assign oRAMWriteEnable = ( wWBM_Address_Selector == `GFSM_SELECT_TFU ) ? wRAMWriteEnable_TFU : wRAMWriteEnable_TNF;

assign oAddressWBM_IsImm =

( !iTexturingEnable || (iTexturingEnable &&

 (wWBM_Address_Selector == `GFSM_SELECT_TFU || wWBM_Address_Selector == `GFSM_SELECT_TNF) ))

 ? 1'b1 : 1'b0;

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

//Mux for oRAMWriteAddress

MUXFULLPARALELL_16bits_2SEL_X MUXGE_1B

(

        .I1( wRAMWriteAddress_TFU ),

        .I2( wRAMWriteAddress_TFF ),

        .I3( wRAMWriteAddress_TNF ),

        .O1( oRAMWriteAddress ),

        .Sel( wWBM_Address_Selector )

);

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

assign oSetAddressWBM = wTNF2__SetAddressWBM | wTFU2__SetAddressWBM | wTFF2__SetAddressWBM;

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

/*

        Tree node fetcher: Takes care of resquesting

        node information. TNF requests Read Bus Cycles

        from the Wish Bone Master Unit. TNF is controlled

        by the GFSM.

*/

TreeNodeFetcher TNF

(

        .Clock( Clock ),

        .Reset( Reset ),

        .iData(                    iData_WBM                     ),

        .iDataAvailable(           iDataReady_WBM                ),

        .oEnableWBM(         wTFN_Enable_WBM              ),

        .oSetAddressWBM(           wTNF2__SetAddressWBM          ),

        .oAddressWBM(              wAddress_TNF                  ),

        .iInitialAddress(          wNodeAddress                  ),

        .iTrigger(                 wTrigger_TNF                  ),

        .oNode_IsLeaf(             wNode_IsLeaf                  ),

        .oNodeReadDone(            wNodeReadDone                 ),

        .oNode_TriangleCount(      wNode_TriangleCount           ),

        .oNode_Brother_Address(    wNode_Brother_Address         ),

        .oParents_Brother_Address( wParents_Brother_Address      ),

        .oNode_DataOffset(         wTNF2_TFU__TriangleDataOffset ),

        .oRAMWriteEnable(          wRAMWriteEnable_TNF           ),

        .oRAMWriteAddress(         wRAMWriteAddress_TNF          )

);

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

/*

        Triangle Fetch Unit: Takes care of resquesting

        triangle information. TFU requests Read Bus Cycles

        from the Wish Bone Master Unit. TFU is controlled

        by the GFSM.

*/

TriangleFetchUnit TFU

(

        .Clock( Clock ),

        .Reset( Reset ),

        .iTrigger(                     wTrigger_TFU                  ),

        .iInitialAddress(              wTNF2_TFU__TriangleDataOffset ),

        .iSetAddressOffset(            wGFSM2_TFU__SetAddressOffset  ),

        .iDataAvailable(               iDataReady_WBM                ),

        .oAddressWBM(                  wAddress_TFU                  ),

        .oSetAddressWBM(               wTFU2__SetAddressWBM          ),

        .oTriggerWBM(                  wTFU_Trigger_WBM              ),

        .oRAMWriteEnable(              wRAMWriteEnable_TFU           ),

        .iCR_TextureMappingEnabled(    iTexturingEnable              ),

        .oRAMWriteAddress(             wRAMWriteAddress_TFU          ),

        .oDone(                        wTriangleReadDone             )

);

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

/*

        Geometry Fetch Finite State Machine: Takes care of resquesting

        the control of the various geometry fetching routines. It controls

        TFF,TFU and TNF.

*/

GeometryFetchFSM  GFSM //TODO: Add new states to fetch the texures

(

        .Clock( Clock ),

        .Reset( Reset ),

        .iBIUHit(                       iBIUHit                      ),

        .iTexturingEnable(              iTexturingEnable             ),

        .iEnable(                       iEnable                      ),

        .iAABBIUHit(                    iMicroCodeReturnValue        ),

        .iUCodeDone(                    iMicrocodeExecutionDone      ),

        .iTriangleReadDone(             wTriangleReadDone            ),

        .iNode_TriangleCount(           wNode_TriangleCount          ),

        .iNode_Brother_Address(         wNode_Brother_Address        ),

        .iNode_Parents_Brother_Address( wParents_Brother_Address     ),

        .iNode_IsLeaf(                  wNode_IsLeaf                 ),

        .iNodeReadDone(                 wNodeReadDone                ),

        .oTrigger_TNF(                  wTrigger_TNF                 ),

        .oTrigger_TFU(                  wTrigger_TFU                 ),

        .oNodeAddress(                  wNodeAddress                 ),

        .oRequest_AABBIU(               oRequest_AABBIU              ),

        .oRequest_BIU(                  oRequest_BIU                 ),

        .oRequest_TCC(                  oRequest_TCC                 ),

        .oWBM_Addr_Selector(            wWBM_Address_Selector        ),

        .oSync(                         oSync                        ),

        .oSetTFUAddressOffset(          wGFSM2_TFU__SetAddressOffset ),

        .oDone(                         oDone                        ),

        .iDataAvailable(                                  iDataReady_WBM               ),

        .oEnable_WBM(                             wTFF_Trigger_WBM             ),

        .oAddressWBM(                                     oAddressWBM_fromMEM          ),

        .oSetAddressWBM(                                  wTFF2__SetAddressWBM         ),

        .iTrigger_TFF(                  iTrigger_TFF                 ),

        .oSetIOWriteBackAddr(           oSetIOWriteBackAddr          ),

        .oRAMTextureStoreLocation(      wRAMWriteAddress_TFF         )

);

assign oTFFDone = oDone;

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

endmodule