path: root/src/mesa/drivers/dri/unichrome/via_ioctl.c

/*
 * Copyright 1998-2003 VIA Technologies, Inc. All Rights Reserved.
 * Copyright 2001-2003 S3 Graphics, Inc. All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sub license,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * VIA, S3 GRAPHICS, AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */
#include <stdio.h>
#include <unistd.h>

#include "glheader.h"
#include "mtypes.h"
#include "macros.h"
#include "dd.h"
#include "swrast/swrast.h"

#include "mm.h"
#include "via_context.h"
#include "via_tris.h"
#include "via_ioctl.h"
#include "via_state.h"

#include "vblank.h"
#include "drm.h"
#include "xf86drm.h"
#include <sys/ioctl.h>
#include <errno.h>


#define VIA_REG_STATUS          0x400
#define VIA_REG_GEMODE          0x004
#define VIA_REG_SRCBASE         0x030
#define VIA_REG_DSTBASE         0x034
#define VIA_REG_PITCH           0x038      
#define VIA_REG_SRCCOLORKEY     0x01C      
#define VIA_REG_KEYCONTROL      0x02C       
#define VIA_REG_SRCPOS          0x008
#define VIA_REG_DSTPOS          0x00C
#define VIA_REG_GECMD           0x000
#define VIA_REG_DIMENSION       0x010       /* width and height */
#define VIA_REG_FGCOLOR         0x018

#define VIA_GEM_8bpp            0x00000000
#define VIA_GEM_16bpp           0x00000100
#define VIA_GEM_32bpp           0x00000300
#define VIA_GEC_BLT             0x00000001
#define VIA_PITCH_ENABLE        0x80000000
#define VIA_GEC_INCX            0x00000000
#define VIA_GEC_DECY            0x00004000
#define VIA_GEC_INCY            0x00000000
#define VIA_GEC_DECX            0x00008000
#define VIA_GEC_FIXCOLOR_PAT    0x00002000


#define VIA_BLIT_CLEAR 0x00
#define VIA_BLIT_COPY 0xCC
#define VIA_BLIT_FILL 0xF0
#define VIA_BLIT_SET 0xFF

 
void viaCheckDma(viaContextPtr vmesa, GLuint bytes)
{
    VIA_FINISH_PRIM( vmesa );
    if (vmesa->dmaLow + bytes > VIA_DMA_HIGHWATER) {
	viaFlushDma(vmesa);
    }
}



#define SetReg2DAGP(nReg, nData) do {		\
    OUT_RING( ((nReg) >> 2) | 0xF0000000 );	\
    OUT_RING( nData );				\
} while (0)


static void viaBlit(viaContextPtr vmesa, GLuint bpp,
		    GLuint srcBase, GLuint srcPitch, 
		    GLuint dstBase, GLuint dstPitch,
		    GLuint w, GLuint h, 
		    GLuint blitMode, 
		    GLuint color, GLuint nMask ) 
{

    GLuint dwGEMode, srcX, dstX, cmd;
    RING_VARS;

    if (VIA_DEBUG)
       fprintf(stderr, "%s bpp %d src %x/%x dst %x/%x w %d h %d  mode: %x color: 0x%08x mask 0x%08x\n",
	       __FUNCTION__, bpp, srcBase, srcPitch, dstBase, dstPitch, w,h, blitMode, color, nMask);


    if (!w || !h)
        return;

    switch (bpp) {
    case 16:
        dwGEMode = VIA_GEM_16bpp;
	srcX = (srcBase & 0x1f) >> 1;
	dstX = (dstBase & 0x1f) >> 1;
        break;
    case 32:
        dwGEMode = VIA_GEM_32bpp;
	srcX = (srcBase & 0x1f) >> 2;
	dstX = (dstBase & 0x1f) >> 2;
	break;
    default:
        return;
    }

    switch(blitMode) {
    case VIA_BLIT_FILL:
	cmd = VIA_GEC_BLT | VIA_GEC_FIXCOLOR_PAT | (VIA_BLIT_FILL << 24);
	break;
    case VIA_BLIT_COPY:
	cmd = VIA_GEC_BLT | (VIA_BLIT_COPY << 24);
	break;
    default:
        return;
    }	

    BEGIN_RING(22);
    SetReg2DAGP( VIA_REG_GEMODE, dwGEMode);
    SetReg2DAGP( VIA_REG_FGCOLOR, color);
    SetReg2DAGP( 0x2C, nMask);
    SetReg2DAGP( VIA_REG_SRCBASE, (srcBase & ~0x1f) >> 3);
    SetReg2DAGP( VIA_REG_DSTBASE, (dstBase & ~0x1f) >> 3);
    SetReg2DAGP( VIA_REG_PITCH, VIA_PITCH_ENABLE |
	       (srcPitch >> 3) | ((dstPitch >> 3) << 16));
    SetReg2DAGP( VIA_REG_SRCPOS, srcX);
    SetReg2DAGP( VIA_REG_DSTPOS, dstX);
    SetReg2DAGP( VIA_REG_DIMENSION, (((h - 1) << 16) | (w - 1)));
    SetReg2DAGP( VIA_REG_GECMD, cmd);
    SetReg2DAGP( 0x2C, 0x00000000);
    ADVANCE_RING();
}

static void viaFillBuffer(viaContextPtr vmesa,
			  viaBuffer *buffer,
			  drm_clip_rect_t *pbox,
			  int nboxes,
			  GLuint pixel,
			  GLuint mask)
{
   GLuint bytePerPixel = buffer->bpp >> 3;
   GLuint i;

   for (i = 0; i < nboxes ; i++) {        
      int x = pbox[i].x1 - vmesa->drawX;
      int y = pbox[i].y1 - vmesa->drawY;
      int w = pbox[i].x2 - pbox[i].x1;
      int h = pbox[i].y2 - pbox[i].y1;

      int offset = (buffer->orig + 
		    y * buffer->pitch + 
		    x * bytePerPixel);

      viaBlit(vmesa,
	      buffer->bpp, 
	      offset, buffer->pitch,
	      offset, buffer->pitch, 
	      w, h,
	      VIA_BLIT_FILL, pixel, mask); 
   }
}



static void viaClear(GLcontext *ctx, GLbitfield mask, GLboolean all,
                     GLint cx, GLint cy, GLint cw, GLint ch)
{
   viaContextPtr vmesa = VIA_CONTEXT(ctx);
   __DRIdrawablePrivate *dPriv = vmesa->driDrawable;
   int flag = 0;
   GLuint i = 0;
   GLuint clear_depth_mask = 0xf << 28;
   GLuint clear_depth = 0;

   VIA_FLUSH_DMA(vmesa);

   if (mask & DD_FRONT_LEFT_BIT) {
      flag |= VIA_FRONT;
      mask &= ~DD_FRONT_LEFT_BIT;
   }

   if (mask & DD_BACK_LEFT_BIT) {
      flag |= VIA_BACK;	
      mask &= ~DD_BACK_LEFT_BIT;
   }

   if (mask & DD_DEPTH_BIT) {
      flag |= VIA_DEPTH;
      clear_depth = (GLuint)(ctx->Depth.Clear * vmesa->ClearDepth);
      clear_depth_mask &= ~vmesa->depth_clear_mask;
      mask &= ~DD_DEPTH_BIT;
   }
    
   if (mask & DD_STENCIL_BIT) {
      if (vmesa->have_hw_stencil) {
	 if (ctx->Stencil.WriteMask[0] == 0xff) {
	    flag |= VIA_DEPTH;
	    clear_depth &= ~0xff;
	    clear_depth |= (ctx->Stencil.Clear & 0xff);
	    clear_depth_mask &= ~vmesa->stencil_clear_mask;
	    mask &= ~DD_STENCIL_BIT;
	 }
	 else {
	    if (VIA_DEBUG)
	       fprintf(stderr, "XXX: Clear stencil writemask %x -- need triangles (or a ROP?)\n", 
		       ctx->Stencil.WriteMask[0]);
	 }
      }
   }
    
   if (flag) {
      drm_clip_rect_t *boxes, *tmp_boxes = 0;
      int nr = 0;

      LOCK_HARDWARE(vmesa);
	    
      /* flip top to bottom */
      cy = dPriv->h - cy - ch;
      cx += vmesa->drawX + vmesa->drawXoff;
      cy += vmesa->drawY;
        
      if (!all) {
	 drm_clip_rect_t *b = vmesa->pClipRects;	 
	 
	 boxes = tmp_boxes = (drm_clip_rect_t *)malloc(vmesa->numClipRects * 
						       sizeof(drm_clip_rect_t)); 
	 if (!boxes) {
	    UNLOCK_HARDWARE(vmesa);
	    return;
	 }

	 for (; i < vmesa->numClipRects; i++) {
	    GLint x = b[i].x1;
	    GLint y = b[i].y1;
	    GLint w = b[i].x2 - x;
	    GLint h = b[i].y2 - y;

	    if (x < cx) w -= cx - x, x = cx;
	    if (y < cy) h -= cy - y, y = cy;
	    if (x + w > cx + cw) w = cx + cw - x;
	    if (y + h > cy + ch) h = cy + ch - y;
	    if (w <= 0) continue;
	    if (h <= 0) continue;

	    boxes[nr].x1 = x;
	    boxes[nr].y1 = y;
	    boxes[nr].x2 = x + w;
	    boxes[nr].y2 = y + h;
	    nr++;
	 }
      }
      else {
	 boxes = vmesa->pClipRects;
	 nr = vmesa->numClipRects;
      }
	    
      if (flag & VIA_FRONT) {
	 viaFillBuffer(vmesa, &vmesa->front, boxes, nr, vmesa->ClearColor, vmesa->ClearMask);
      } 
		
      if (flag & VIA_BACK) {
	 viaFillBuffer(vmesa, &vmesa->back, boxes, nr, vmesa->ClearColor, vmesa->ClearMask);
      }

      if (flag & VIA_DEPTH) {
	 viaFillBuffer(vmesa, &vmesa->depth, boxes, nr, clear_depth, clear_depth_mask);
      }		

      viaFlushDmaLocked(vmesa, VIA_NO_CLIPRECTS);
      UNLOCK_HARDWARE(vmesa);

      if (tmp_boxes)
	 free(tmp_boxes);
   }
   
   if (mask)
      _swrast_Clear(ctx, mask, all, cx, cy, cw, ch);
}




static void viaDoSwapBuffers(viaContextPtr vmesa,
			     drm_clip_rect_t *b,
			     GLuint nbox)
{    
   GLuint bytePerPixel = vmesa->viaScreen->bitsPerPixel >> 3;
   viaBuffer *front = &vmesa->front;
   viaBuffer *back = &vmesa->back;
   GLuint i;
        
   for (i = 0; i < nbox; i++, b++) {        
      GLint x = b->x1 - vmesa->drawX;
      GLint y = b->y1 - vmesa->drawY;
      GLint w = b->x2 - b->x1;
      GLint h = b->y2 - b->y1;
	
      GLuint src = back->orig + y * back->pitch + x * bytePerPixel;
      GLuint dest = front->orig + y * front->pitch + x * bytePerPixel;

      viaBlit(vmesa, 
	      bytePerPixel << 3, 
	      src, back->pitch,
	      dest, front->pitch,
	      w, h,
	      VIA_BLIT_COPY, 0, 0); 
   }
}




/*
 * Copy the back buffer to the front buffer. 
 */
void viaCopyBuffer(const __DRIdrawablePrivate *dPriv)
{
   viaContextPtr vmesa = (viaContextPtr)dPriv->driContextPriv->driverPrivate;
   GLboolean missed_target;

   VIA_FLUSH_DMA(vmesa);
   driWaitForVBlank( dPriv, & vmesa->vbl_seq, vmesa->vblank_flags, & missed_target );
   if ( missed_target ) {
      vmesa->swap_missed_count++;
      vmesa->get_ust( &vmesa->swap_missed_ust );
   }
   LOCK_HARDWARE(vmesa);

   viaDoSwapBuffers(vmesa, dPriv->pClipRects, dPriv->numClipRects);
   viaFlushDmaLocked(vmesa, VIA_NO_CLIPRECTS);

   UNLOCK_HARDWARE(vmesa);
   vmesa->swap_count++;
   vmesa->get_ust( &vmesa->swap_ust );
}

/*
 * XXX implement when full-screen extension is done.
 */
void viaPageFlip(const __DRIdrawablePrivate *dPriv)
{
    viaContextPtr vmesa = (viaContextPtr)dPriv->driContextPriv->driverPrivate;
    viaBuffer buffer_tmp;
    GLboolean missed_target;


    VIA_FLUSH_DMA(vmesa);
    driWaitForVBlank( dPriv, &vmesa->vbl_seq, vmesa->vblank_flags, &missed_target );
    if ( missed_target ) {
       vmesa->swap_missed_count++;
       vmesa->get_ust( &vmesa->swap_missed_ust );
    }
    LOCK_HARDWARE(vmesa);

    {
        RING_VARS;

	if (!vmesa->nDoneFirstFlip) {
    	    vmesa->nDoneFirstFlip = GL_FALSE; /* XXX: FIXME LATER!!! */
	    BEGIN_RING(4);
    	    OUT_RING(HALCYON_HEADER2);
    	    OUT_RING(0x00fe0000);
    	    OUT_RING(0x0000000e);
    	    OUT_RING(0x0000000e);
	    ADVANCE_RING();
	}

	BEGIN_RING(4);
	OUT_RING( HALCYON_HEADER2 );
	OUT_RING( 0x00fe0000 );
	OUT_RING((HC_SubA_HFBBasL << 24) | (vmesa->back.offset & 0xFFFFF8) | 0x2);
	OUT_RING((HC_SubA_HFBDrawFirst << 24) |
		 ((vmesa->back.offset & 0xFF000000) >> 24) | 0x0100);
	ADVANCE_RING();

    }

    viaFlushDmaLocked(vmesa, VIA_NO_CLIPRECTS);    
    UNLOCK_HARDWARE(vmesa);
    vmesa->swap_count++;
    vmesa->get_ust( &vmesa->swap_ust );

    /* KW: FIXME: When buffers are freed, could free frontbuffer by
     * accident:
     */
    memcpy(&buffer_tmp, &vmesa->back, sizeof(viaBuffer));
    memcpy(&vmesa->back, &vmesa->front, sizeof(viaBuffer));
    memcpy(&vmesa->front, &buffer_tmp, sizeof(viaBuffer));
    
    if(vmesa->currentPage) {
	vmesa->currentPage = 0;
    }
    else {
	vmesa->currentPage = 1;
    }

    if (VIA_DEBUG) fprintf(stderr, "%s - out\n", __FUNCTION__);        
}




#define VIA_CMDBUF_MAX_LAG 50000

static int fire_buffer(viaContextPtr vmesa)
{
   drmVIACommandBuffer bufI;
   int ret;

   bufI.buf = (char *)vmesa->dma;
   bufI.size = vmesa->dmaLow;

   if (vmesa->useAgp) {
      drmVIACmdBufSize bSiz;

      /* Do the CMDBUF_SIZE ioctl:
       */
      bSiz.func = VIA_CMDBUF_LAG;
      bSiz.wait = 1;
      bSiz.size = VIA_CMDBUF_MAX_LAG;
      do {
	 ret = drmCommandWriteRead(vmesa->driFd, DRM_VIA_CMDBUF_SIZE, 
				   &bSiz, sizeof(bSiz));
      } while (ret == -EAGAIN);
      if (ret) {
	 fprintf(stderr, "%s: DRM_VIA_CMDBUF_SIZE returned %d\n", __FUNCTION__, ret);
	 abort();
	 return ret;
      }

      /* Acutally fire the buffer:
       */
      do {
	 ret = drmCommandWrite(vmesa->driFd, DRM_VIA_CMDBUFFER, 
			       &bufI, sizeof(bufI));
      } while (ret == -EAGAIN);
      if (ret) {
	 fprintf(stderr, "%s: DRM_VIA_CMDBUFFER returned %d\n", __FUNCTION__, ret);
	 abort();
	 /* If this fails, the original code fell back to the PCI path. 
	  */
      }
      else 
	 return 0;

      /* Fall through to PCI handling?!?
       */
      WAIT_IDLE(vmesa);
   }
	    
   ret = drmCommandWrite(vmesa->driFd, DRM_VIA_PCICMD, &bufI, sizeof(bufI));
   if (ret) {
      fprintf(stderr, "%s: DRM_VIA_PCICMD returned %d\n", __FUNCTION__, ret);
      abort();
   }

   return ret;
}


/* Inserts the surface addresss and active cliprects one at a time
 * into the head of the DMA buffer being flushed.  Fires the buffer
 * for each cliprect.
 */
static void via_emit_cliprect(viaContextPtr vmesa,
			      drm_clip_rect_t *b) 
{
   viaBuffer *buffer = vmesa->drawBuffer;
   GLuint *vb = (GLuint *)(vmesa->dma + vmesa->dmaCliprectAddr);

   GLuint format = (vmesa->viaScreen->bitsPerPixel == 0x20 
		    ? HC_HDBFM_ARGB8888 
		    : HC_HDBFM_RGB565);

   GLuint pitch = buffer->pitch;
   GLuint offset = buffer->orig;

   if (0)
      fprintf(stderr, "emit cliprect for box %d,%d %d,%d\n", b->x1, b->y1, b->x2, b->y2);

   vb[0] = HC_HEADER2;
   vb[1] = (HC_ParaType_NotTex << 16);

   if (vmesa->driDrawable->w == 0 || vmesa->driDrawable->h == 0) {
      vb[2] = (HC_SubA_HClipTB << 24) | 0x0;
      vb[3] = (HC_SubA_HClipLR << 24) | 0x0;
   }
   else {
      vb[2] = (HC_SubA_HClipTB << 24) | (b->y1 << 12) | b->y2;
      vb[3] = (HC_SubA_HClipLR << 24) | (b->x1 << 12) | b->x2;
   }
	    
   vb[4] = ((HC_SubA_HDBBasL << 24) | (offset & 0xFFFFFF));
   vb[5] = ((HC_SubA_HDBBasH << 24) | ((offset & 0xFF000000)) >> 24); 
   vb[6] = ((HC_SubA_HDBFM << 24) | HC_HDBLoc_Local | format | pitch);            
   vb[7] = 0xcccccccc;
}



static int intersect_rect(drm_clip_rect_t *out,
                          drm_clip_rect_t *a,
                          drm_clip_rect_t *b)
{
    *out = *a;
    
    if (0)
       fprintf(stderr, "intersect %d,%d %d,%d and %d,%d %d,%d\n", 
	       a->x1, a->y1, a->x2, a->y2,
	       b->x1, b->y1, b->x2, b->y2);

    if (b->x1 > out->x1) out->x1 = b->x1;
    if (b->x2 < out->x2) out->x2 = b->x2;
    if (out->x1 >= out->x2) return 0;

    if (b->y1 > out->y1) out->y1 = b->y1;
    if (b->y2 < out->y2) out->y2 = b->y2;
    if (out->y1 >= out->y2) return 0;

    return 1;
}

static void dump_dma( viaContextPtr vmesa )
{
   GLuint i;
   GLuint *data = (GLuint *)vmesa->dma;
   for (i = 0; i < vmesa->dmaLow; i += 16) {
      fprintf(stderr, "%04x:   ", i);
      fprintf(stderr, "%08x  ", *data++);
      fprintf(stderr, "%08x  ", *data++);
      fprintf(stderr, "%08x  ", *data++);
      fprintf(stderr, "%08x\n", *data++);
   }
   fprintf(stderr, "******************************************\n");
}


void viaFlushDmaLocked(viaContextPtr vmesa, GLuint flags)
{
   int i;
   RING_VARS;

   if (VIA_DEBUG)
      fprintf(stderr, "%s\n", __FUNCTION__);

   if (*(GLuint *)vmesa->driHwLock != (DRM_LOCK_HELD|vmesa->hHWContext) &&
       *(GLuint *)vmesa->driHwLock != (DRM_LOCK_HELD|DRM_LOCK_CONT|vmesa->hHWContext)) {
      fprintf(stderr, "%s called without lock held\n", __FUNCTION__);
      abort();
   }

   if (vmesa->dmaLow == 0) {
      return;
   }

   assert(vmesa->dmaLastPrim == 0);

   /* viaFinishPrimitive can add up to 8 bytes beyond VIA_DMA_HIGHWATER:
    */
   if (vmesa->dmaLow > VIA_DMA_HIGHWATER + 8) {
      fprintf(stderr, "buffer overflow in Flush Prims = %d\n",vmesa->dmaLow);
      abort();
   }

   switch (vmesa->dmaLow & 0x1F) {	
   case 8:
      BEGIN_RING_NOCHECK( 6 );
      OUT_RING( HC_HEADER2 );
      OUT_RING( (HC_ParaType_NotTex << 16) );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      ADVANCE_RING();
      break;
   case 16:
      BEGIN_RING_NOCHECK( 4 );
      OUT_RING( HC_HEADER2 );
      OUT_RING( (HC_ParaType_NotTex << 16) );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      ADVANCE_RING();
      break;    
   case 24:
      BEGIN_RING_NOCHECK( 10 );
      OUT_RING( HC_HEADER2 );
      OUT_RING( (HC_ParaType_NotTex << 16) );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );
      OUT_RING( HC_DUMMY );	
      ADVANCE_RING();
      break;    
   case 0:
      break;
   default:
      if (VIA_DEBUG)
	 fprintf(stderr, "%s: unaligned value for vmesa->dmaLow: %x\n",
		 __FUNCTION__, vmesa->dmaLow);
   }


   if (VIA_DEBUG)
      dump_dma( vmesa );

   if (flags & VIA_NO_CLIPRECTS) {
      if (0) fprintf(stderr, "%s VIA_NO_CLIPRECTS\n", __FUNCTION__);
      assert(vmesa->dmaCliprectAddr == ~0);
      fire_buffer( vmesa );
   }
   else if (vmesa->dmaCliprectAddr == ~0) {
      /* Contains only state.  Could just dump the packet?
       */
      if (0) fprintf(stderr, "%s: no dmaCliprectAddr\n", __FUNCTION__);
      if (0) fire_buffer( vmesa );
   }
   else if (vmesa->numClipRects) {
      drm_clip_rect_t *pbox = vmesa->pClipRects;
      if (0) fprintf(stderr, "%s: %d cliprects\n", __FUNCTION__, vmesa->numClipRects);
      
      for (i = 0; i < vmesa->numClipRects; i++) {
	 drm_clip_rect_t b;

	 b.x1 = pbox[i].x1 - (vmesa->drawX + vmesa->drawXoff);
	 b.x2 = pbox[i].x2 - (vmesa->drawX + vmesa->drawXoff);
	 b.y1 = pbox[i].y1 - vmesa->drawY;
	 b.y2 = pbox[i].y2 - vmesa->drawY;

	 if (vmesa->glCtx->Scissor.Enabled &&
	     !intersect_rect(&b, &b, &vmesa->scissorRect)) 
	    continue;

	 b.x1 += vmesa->drawXoff;
	 b.x2 += vmesa->drawXoff;

	 via_emit_cliprect(vmesa, &b);

	 if (fire_buffer(vmesa) != 0)
	    goto done;
      }
   } else {
      if (0) fprintf(stderr, "%s: no cliprects\n", __FUNCTION__);
      UNLOCK_HARDWARE(vmesa);
      sched_yield();
      LOCK_HARDWARE(vmesa);
   }

 done:
   /* Reset vmesa vars:
    */
   vmesa->dmaLow = 0;
   vmesa->dmaCliprectAddr = ~0;
   vmesa->newEmitState = ~0;
}

static void viaWrapPrimitive( viaContextPtr vmesa )
{
   GLenum renderPrimitive = vmesa->renderPrimitive;
   GLenum hwPrimitive = vmesa->hwPrimitive;

   if (VIA_DEBUG) fprintf(stderr, "%s\n", __FUNCTION__);
   
   if (vmesa->dmaLastPrim)
      viaFinishPrimitive( vmesa );
   
   viaFlushDma(vmesa);

   if (renderPrimitive != GL_POLYGON + 1)
      viaRasterPrimitive( vmesa->glCtx,
			  renderPrimitive,
			  hwPrimitive );

}

void viaFlushDma(viaContextPtr vmesa)
{
   if (vmesa->dmaLow) {
      assert(!vmesa->dmaLastPrim);

      LOCK_HARDWARE(vmesa); 
      viaFlushDmaLocked(vmesa, 0);
      UNLOCK_HARDWARE(vmesa);
   }
}

static void viaFlush(GLcontext *ctx)
{
    viaContextPtr vmesa = VIA_CONTEXT(ctx);
    VIA_FLUSH_DMA(vmesa);
}

static void viaFinish(GLcontext *ctx)
{
    viaContextPtr vmesa = VIA_CONTEXT(ctx);
    VIA_FLUSH_DMA(vmesa);
    WAIT_IDLE(vmesa);
}

static void viaClearStencil(GLcontext *ctx,  int s)
{
    return;
}

void viaInitIoctlFuncs(GLcontext *ctx)
{
    ctx->Driver.Flush = viaFlush;
    ctx->Driver.Clear = viaClear;
    ctx->Driver.Finish = viaFinish;
    ctx->Driver.ClearStencil = viaClearStencil;
}




GLuint *viaAllocDmaFunc(viaContextPtr vmesa, int bytes, const char *func, int line)
{
   assert(!vmesa->dmaLastPrim);
   if (vmesa->dmaLow + bytes > VIA_DMA_HIGHWATER) {
      if (VIA_DEBUG) fprintf(stderr, "buffer overflow in check dma = %d + %d = %d\n", 
			     vmesa->dmaLow, bytes, vmesa->dmaLow + bytes);
      viaFlushDma(vmesa);
   }

   {
      GLuint *start = (GLuint *)(vmesa->dma + vmesa->dmaLow);
      if (0)
	 fprintf(stderr, "%s %04x 0x%x bytes\n", func, vmesa->dmaLow, bytes);
      vmesa->dmaLow += bytes;
      return start;
   }
}


GLuint *viaExtendPrimitive(viaContextPtr vmesa, int bytes)
{
   if (0)
      fprintf(stderr, "%s %d\n", __FUNCTION__, bytes);

   assert(vmesa->dmaLastPrim);
   if (vmesa->dmaLow + bytes > VIA_DMA_HIGHWATER) {
      viaWrapPrimitive(vmesa);
   }

   {
      GLuint *start = (GLuint *)(vmesa->dma + vmesa->dmaLow);
      if (0)
	 fprintf(stderr, "%s %04x 0x%x bytes\n", __FUNCTION__, vmesa->dmaLow, bytes);
      vmesa->dmaLow += bytes;
      return start;
   }
}