/******************************Module*Header**********************************\
*
*                           *******************
*                           * GDI SAMPLE CODE *
*                           *******************
*
* Module Name: sync.c
*
* Content: DrvSynchronize
*
* Copyright (c) 1994-1999 3Dlabs Inc. Ltd. All rights reserved.
* Copyright (c) 1995-2003 Microsoft Corporation.  All rights reserved.
\*****************************************************************************/

#include "precomp.h"
#include "pxrx.h"

/******************************Public*Routine******************************\
* VOID DrvSynchronize
*
* Synchronize with the GLINT.
*
* Before letting GDI draw onto our screen DIBs we must synchronize with GLINT.
* We do this by hooking HOOK_SYNCHRONIZE when we create a DIV that points to
* the screen (or off-screen). GDI then calls DrvSynchronize() before trying
* to render to any of these screen DIBs. The advantage is that we can forget
* about doing SYNC_WITH_GLINT in the code and have GDI call DrvSynchronize
* at the appropriate moment.
*
\**************************************************************************/

VOID
DrvSynchronize(
DHPDEV  dhpdev,
RECTL   *prcl)
{
    PDEV*   ppdev = (PDEV*) dhpdev;
    GLINT_DECL;

    DISPDBG((DBGLVL, "DrvSynchronize called"));

    // These chips use cached syncs

    SYNC_IF_CORE_BUSY;
}

//@@BEGIN_DDKSPLIT
#if 0
#if USE_LD_GLINT_FIFO_FUNCTION

void loadGlintFIFOrelease( GlintDataPtr glintInfo, ULONG tag, ULONG data ) {
/**/
    TEMP_MACRO_VARS;

    LD_GLINT_FIFO_FREE( tag, data );
/*/
    static ULONG    fifoSpace = 0;
    ULONG           *dst;
    TEMP_MACRO_VARS;

    if( fifoSpace < 2 ) {
        GET_INPUT_FIFO_SPACE( fifoSpace );

        if ( GLINT_GAMMA_PRESENT ) {
            if( space > MAX_GAMMA_FIFO_ENTRIES )
                space = MAX_GAMMA_FIFO_ENTRIES;
        }
        else {
            if( space > MAX_P3_FIFO_ENTRIES )
                space = MAX_P3_FIFO_ENTRIES;
        }
    }

    dst = (ULONG *) glintInfo->regs.InFIFOInterface;
    MEMORY_BARRIER();
    WRITE_FAST_ULONG( dst, tag );
    dst++;
    MEMORY_BARRIER();
    WRITE_FAST_ULONG( dst, data );
/**/
}

void loadGlintFIFOdebug( GlintDataPtr glintInfo, ULONG tag, ULONG data ) {
    TEMP_MACRO_VARS;

    LD_GLINT_FIFO_DBG( tag, data )
}

#if DBG
LoadGlintFIFO   loadGlintFIFO = loadGlintFIFOdebug;
#else
LoadGlintFIFO   loadGlintFIFO = loadGlintFIFOrelease;
#endif   // DBG
#endif  // USE_LD_GLINT_FIFO_FUNCTION

#endif // 0
//@@END_DDKSPLIT

#if USE_SYNC_FUNCTION



void syncWithGlint( PPDEV ppdev, GlintDataPtr glintInfo ) 
{
    DWORD   gsync;
    ULONG   bmask;
    TEMP_MACRO_VARS;

    WAIT_DMA_COMPLETE;

    // Setting the pxrxDMA->bFlushRequired flag below to false ensures that 
    // the interrupt routine will not try to write to the chip. Without 
    // this check, the Vblank interrupt can attempt to flush outstanding 2D 
    // rendering by writing ContinueNewSub tag and data to the chip.
    // The problem with this is that the interrupt can occur between the 
    // writes of the tag and data in the code below, and if this happens,
    // the tag and data becomes out of step and typically results in a hang.
    //
    // Note that we have to set a MUTEX otherwise we still get hangs on a 
    // multi-processor system when an interrupt routine can be running 
    // simultaneously on another processor. The MUTEX avoids race conditions.
    
    GET_INTR_CMD_BLOCK_MUTEX(&glintInfo->pInterruptCommandBlock->General);
    glintInfo->pxrxDMA->bFlushRequired = FALSE ;

    WAIT_GLINT_FIFO(4);
    LD_GLINT_FIFO(__GlintTagFilterMode, 0x400);
    LD_GLINT_FIFO(__GlintTagSync, 0);
    LD_GLINT_FIFO(__GlintTagFilterMode, 0x0);
    
    do {
        WAIT_OUTPUT_FIFO_READY;
        READ_OUTPUT_FIFO(gsync);
        DISPDBG((DBGLVL, "SYNC: got 0x%x from output FIFO", gsync));
    } while (gsync != __GlintTagSync);
    
    glintInfo->bGlintCoreBusy = FALSE;
    RELEASE_INTR_CMD_BLOCK_MUTEX(&glintInfo->pInterruptCommandBlock->General);
}


void waitDMAcomplete( PPDEV ppdev, GlintDataPtr glintInfo ) 
{
    TEMP_MACRO_VARS;

    if (ppdev->currentCtxt == glintInfo->ddCtxtId)
    {
        SEND_PXRX_DMA_FORCE;
    }

    if (!(ppdev->g_GlintBoardStatus & GLINT_DMA_COMPLETE)) 
    {
        if (ppdev->g_GlintBoardStatus & GLINT_INTR_CONTEXT) 
        {
            // do any VBLANK wait, wait Q to empty and last DMA to complete
            PINTERRUPT_CONTROL_BLOCK pBlock = glintInfo->pInterruptCommandBlock;
            
            while (pBlock->Control & SUSPEND_DMA_TILL_VBLANK)
            {
                NULL;
            }
            
            while (pBlock->frontIndex != pBlock->backIndex)
            {
                NULL;
            }
        }
        
        if ((GET_DMA_COUNT(_temp_volatile_i)) > 0) 
        {
            do 
            {
                while (--_temp_volatile_i > 0)
                {
                    NULL;
                }
            } while ((GET_DMA_COUNT(_temp_volatile_i)) > 0);
        }
        
        ppdev->g_GlintBoardStatus |= GLINT_DMA_COMPLETE;
    }
}

#endif  // USE_SYNC_FUNCTION