src/mesa/drivers/dri/i830/i830_context.c - third_party/mesa - Git at Google

 /**************************************************************************
  *
  * Copyright 1998-1999 Precision Insight, Inc., Cedar Park, Texas.
  * 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 PRECISION INSIGHT 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.
  *
  * **************************************************************************/
 /* $XFree86: xc/lib/GL/mesa/src/drv/i830/i830_context.c,v 1.9 2003/02/06 04:18:00 dawes Exp $ */

 /*
  * Authors:
  *   Jeff Hartmann <jhartmann@2d3d.com>
  *   Graeme Fisher <graeme@2d3d.co.za>
  *   Abraham vd Merwe <abraham@2d3d.co.za>
  *
  * Heavily Based on I810 driver written by:
  *   Keith Whitwell <keith@tungstengraphics.com>
  */

 #include "glheader.h"
 #include "context.h"
 #include "matrix.h"
 #include "simple_list.h"
 #include "extensions.h"
 #include "imports.h"

 #include "swrast/swrast.h"
 #include "swrast_setup/swrast_setup.h"
 #include "tnl/tnl.h"
 #include "array_cache/acache.h"

 #include "tnl/t_pipeline.h"

 #include "i830_screen.h"
 #include "i830_dri.h"

 #include "i830_state.h"
 #include "i830_tex.h"
 #include "i830_span.h"
 #include "i830_tris.h"
 #include "i830_vb.h"
 #include "i830_ioctl.h"


 #include "utils.h"
 #ifndef I830_DEBUG
 int I830_DEBUG = (0);
 #endif

 /***************************************
  * Mesa's Driver Functions
  ***************************************/

 #define DRIVER_DATE                     "20021115"

 static const GLubyte *i830DDGetString( GLcontext *ctx, GLenum name )
 {
    const char * chipset;
    static char buffer[128];

    switch (name) {
    case GL_VENDOR:
       switch (I830_CONTEXT(ctx)->i830Screen->deviceID) {
       case PCI_CHIP_845_G:
 	 return (GLubyte *)"2d3D, Inc";

       case PCI_CHIP_I830_M:
 	 return (GLubyte *)"VA Linux, Inc";

       case PCI_CHIP_I855_GM:
       case PCI_CHIP_I865_G:
       default:
 	 return (GLubyte *)"Tungsten Graphics, Inc";
       }
       break;

    case GL_RENDERER:
       switch (I830_CONTEXT(ctx)->i830Screen->deviceID) {
       case PCI_CHIP_845_G:
 	 chipset = "Intel(R) 845G"; break;
       case PCI_CHIP_I830_M:
 	 chipset = "Intel(R) 830M"; break;
       case PCI_CHIP_I855_GM:
 	 chipset = "Intel(R) 852GM/855GM"; break;
       case PCI_CHIP_I865_G:
 	 chipset = "Intel(R) 865G"; break;
       default:
 	 chipset = "Unknown Intel Chipset"; break;
       }

       (void) driGetRendererString( buffer, chipset, DRIVER_DATE, 0 );
       return (GLubyte *) buffer;

    default:
       return NULL;
    }
 }

 static void i830BufferSize(GLframebuffer *buffer,
 			   GLuint *width, GLuint *height)
 {
    GET_CURRENT_CONTEXT(ctx);
    i830ContextPtr imesa = I830_CONTEXT(ctx);
    /* Need to lock to make sure the driDrawable is uptodate.  This
     * information is used to resize Mesa's software buffers, so it has
     * to be correct.
     */
    LOCK_HARDWARE(imesa);
    *width = imesa->driDrawable->w;
    *height = imesa->driDrawable->h;
    UNLOCK_HARDWARE(imesa);
 }


 /* Extension strings exported by the i830 driver.
  */
 static const char * const card_extensions[] =
 {
    "GL_ARB_multisample",
    "GL_ARB_multitexture",
    "GL_ARB_texture_border_clamp",
    "GL_ARB_texture_compression",
    "GL_ARB_texture_env_add",
    "GL_ARB_texture_env_combine",
    "GL_ARB_texture_env_dot3",
    "GL_ARB_texture_mirrored_repeat",
    "GL_EXT_blend_color",
    "GL_EXT_blend_func_separate",
    "GL_EXT_blend_minmax",
    "GL_EXT_blend_subtract",
    "GL_EXT_fog_coord",
    "GL_EXT_secondary_color",
    "GL_EXT_stencil_wrap",
    "GL_EXT_texture_edge_clamp",
    "GL_EXT_texture_env_add",
    "GL_EXT_texture_env_combine",
    "GL_EXT_texture_env_dot3",
    "GL_EXT_texture_filter_anisotropic",
    "GL_EXT_texture_lod_bias",
    "GL_IBM_texture_mirrored_repeat",
    "GL_INGR_blend_func_separate",
    "GL_MESA_ycbcr_texture",
    "GL_NV_texture_rectangle",
    "GL_SGIS_generate_mipmap",
    "GL_SGIS_texture_border_clamp",
    "GL_SGIS_texture_edge_clamp",
    NULL
 };


 extern const struct tnl_pipeline_stage _i830_render_stage;

 static const struct tnl_pipeline_stage *i830_pipeline[] = {
    &_tnl_vertex_transform_stage,
    &_tnl_normal_transform_stage,
    &_tnl_lighting_stage,
    &_tnl_fog_coordinate_stage,
    &_tnl_texgen_stage,
    &_tnl_texture_transform_stage,
      				/* REMOVE: point attenuation stage */
 #if 1
    &_i830_render_stage,     /* ADD: unclipped rastersetup-to-dma */
 #endif
    &_tnl_render_stage,
    0,
 };


 static const struct dri_debug_control debug_control[] =
 {
     { "fall",  DEBUG_FALLBACKS },
     { "tex",   DEBUG_TEXTURE },
     { "ioctl", DEBUG_IOCTL },
     { "prim",  DEBUG_PRIMS },
     { "vert",  DEBUG_VERTS },
     { "state", DEBUG_STATE },
     { "verb",  DEBUG_VERBOSE },
     { "dri",   DEBUG_DRI },
     { "dma",   DEBUG_DMA },
     { "san",   DEBUG_SANITY },
     { "sync",  DEBUG_SYNC },
     { "sleep", DEBUG_SLEEP },
     { NULL,    0 }
 };


 GLboolean i830CreateContext( const __GLcontextModes *mesaVis,
                              __DRIcontextPrivate *driContextPriv,
                              void *sharedContextPrivate)
 {
    GLcontext *ctx , *shareCtx;
    i830ContextPtr imesa;
    __DRIscreenPrivate *sPriv = driContextPriv->driScreenPriv;
    i830ScreenPrivate *screen = (i830ScreenPrivate *)sPriv->private;
    I830SAREAPtr saPriv=(I830SAREAPtr)
        (((GLubyte *)sPriv->pSAREA)+screen->sarea_priv_offset);

    /* Allocate i830 context */
    imesa = (i830ContextPtr) CALLOC_STRUCT(i830_context_t);
    if (!imesa) return GL_FALSE;

    /* Allocate the Mesa context */
    if (sharedContextPrivate)
      shareCtx = ((i830ContextPtr) sharedContextPrivate)->glCtx;
    else
      shareCtx = NULL;
    imesa->glCtx = _mesa_create_context(mesaVis, shareCtx, (void*) imesa, GL_TRUE);
    if (!imesa->glCtx) {
       FREE(imesa);
       return GL_FALSE;
    }
    driContextPriv->driverPrivate = imesa;


    imesa->i830Screen = screen;
    imesa->driScreen = sPriv;
    imesa->sarea = saPriv;
    imesa->glBuffer = NULL;


    (void) memset( imesa->texture_heaps, 0, sizeof( imesa->texture_heaps ) );
    make_empty_list( & imesa->swapped );

    imesa->nr_heaps = 1;
    imesa->texture_heaps[0] = driCreateTextureHeap( 0, imesa,
 	    screen->textureSize,
 	    12,
 	    I830_NR_TEX_REGIONS,
 	    imesa->sarea->texList,
 	    & imesa->sarea->texAge,
 	    & imesa->swapped,
 	    sizeof( struct i830_texture_object_t ),
 	    (destroy_texture_object_t *) i830DestroyTexObj );


    /* Set the maximum texture size small enough that we can guarantee
     * that both texture units can bind a maximal texture and have them
     * in memory at once.
     */

    ctx = imesa->glCtx;
    ctx->Const.MaxTextureUnits = 2;

    /* FIXME: driCalcualteMaxTextureLevels assumes that mipmaps are tightly
     * FIXME: packed, but they're not in Intel graphics hardware.
     */
    driCalculateMaxTextureLevels( imesa->texture_heaps,
 				 imesa->nr_heaps,
 				 & ctx->Const,
 				 4,
 				 11, /* max 2D texture size is 2048x2048 */
 				 0,  /* 3D textures unsupported */
 				 0,  /* cube textures unsupported. */
 				 0,  /* texture rectangles unsupported. */
 				 12,
 				 GL_FALSE );

    ctx->Const.MaxTextureMaxAnisotropy = 2.0;

    ctx->Const.MinLineWidth = 1.0;
    ctx->Const.MinLineWidthAA = 1.0;
    ctx->Const.MaxLineWidth = 3.0;
    ctx->Const.MaxLineWidthAA = 3.0;
    ctx->Const.LineWidthGranularity = 1.0;

    ctx->Const.MinPointSize = 1.0;
    ctx->Const.MinPointSizeAA = 1.0;
    ctx->Const.MaxPointSize = 255.0;
    ctx->Const.MaxPointSizeAA = 3.0;
    ctx->Const.PointSizeGranularity = 1.0;

    ctx->Driver.GetBufferSize = i830BufferSize;
    ctx->Driver.ResizeBuffers = _swrast_alloc_buffers;
    ctx->Driver.GetString = i830DDGetString;

    /* Who owns who? */
    ctx->DriverCtx = (void *) imesa;
    imesa->glCtx = ctx;

    /* Initialize the software rasterizer and helper modules. */
    _swrast_CreateContext( ctx );
    _ac_CreateContext( ctx );
    _tnl_CreateContext( ctx );
    _swsetup_CreateContext( ctx );

    /* Install the customized pipeline: */
    _tnl_destroy_pipeline( ctx );
    _tnl_install_pipeline( ctx, i830_pipeline );

    /* Configure swrast to match hardware characteristics: */
    _swrast_allow_pixel_fog( ctx, GL_FALSE );
    _swrast_allow_vertex_fog( ctx, GL_TRUE );

    /* Dri stuff */
    imesa->hHWContext = driContextPriv->hHWContext;
    imesa->driFd = sPriv->fd;
    imesa->driHwLock = &sPriv->pSAREA->lock;
    imesa->vertex_format = 0;

    imesa->hw_stencil = mesaVis->stencilBits && mesaVis->depthBits == 24;

    switch(mesaVis->depthBits) {
    case 16:
       imesa->depth_scale = 1.0/0xffff;
       imesa->depth_clear_mask = ~0;
       imesa->ClearDepth = 0xffff;
       break;
    case 24:
       imesa->depth_scale = 1.0/0xffffff;
       imesa->depth_clear_mask = 0x00ffffff;
       imesa->stencil_clear_mask = 0xff000000;
       imesa->ClearDepth = 0x00ffffff;
       break;
    case 32: /* Not supported */
    default:
       break;
    }
    /* Completely disable stenciling for now, there are some serious issues
     * with stencil.
     */
 #if 0
    imesa->hw_stencil = 0;
 #endif

    imesa->RenderIndex = ~0;
    imesa->dirty = ~0;
    imesa->upload_cliprects = GL_TRUE;

    imesa->CurrentTexObj[0] = 0;
    imesa->CurrentTexObj[1] = 0;

    imesa->do_irqs = (imesa->i830Screen->irq_active &&
 		     !getenv("I830_NO_IRQS"));

    _math_matrix_ctr (&imesa->ViewportMatrix);

    driInitExtensions( ctx, card_extensions, GL_TRUE );
    i830DDInitStateFuncs( ctx );
    i830DDInitTextureFuncs( ctx );
    i830InitTriFuncs (ctx);
    i830DDInitSpanFuncs( ctx );
    i830DDInitIoctlFuncs( ctx );
    i830InitVB (ctx);
    i830DDInitState (ctx);

 #if DO_DEBUG
    I830_DEBUG  = driParseDebugString( getenv( "I830_DEBUG" ),
 				      debug_control );
    I830_DEBUG |= driParseDebugString( getenv( "INTEL_DEBUG" ),
 				      debug_control );
 #endif

    if (getenv("I830_NO_RAST") ||
        getenv("INTEL_NO_RAST")) {
       fprintf(stderr, "disabling 3D rasterization\n");
       FALLBACK(imesa, I830_FALLBACK_USER, 1);
    }


    return GL_TRUE;
 }

 void i830DestroyContext(__DRIcontextPrivate *driContextPriv)
 {
    i830ContextPtr imesa = (i830ContextPtr) driContextPriv->driverPrivate;

    assert(imesa); /* should never be null */
    if (imesa) {
       GLboolean   release_texture_heaps;


       release_texture_heaps = (imesa->glCtx->Shared->RefCount == 1);
       _swsetup_DestroyContext (imesa->glCtx);
       _tnl_DestroyContext (imesa->glCtx);
       _ac_DestroyContext (imesa->glCtx);
       _swrast_DestroyContext (imesa->glCtx);

       i830FreeVB (imesa->glCtx);

       /* free the Mesa context */
       imesa->glCtx->DriverCtx = NULL;
       _mesa_destroy_context(imesa->glCtx);

       if ( release_texture_heaps ) {
          /* This share group is about to go away, free our private
           * texture object data.
           */
          int i;

 	 assert( is_empty_list( & imesa->swapped ) );

          for ( i = 0 ; i < imesa->nr_heaps ; i++ ) {
 	    driDestroyTextureHeap( imesa->texture_heaps[ i ] );
 	    imesa->texture_heaps[ i ] = NULL;
          }
       }

       Xfree (imesa);
    }
 }

 void i830XMesaSetFrontClipRects( i830ContextPtr imesa )
 {
    __DRIdrawablePrivate *dPriv = imesa->driDrawable;

    imesa->numClipRects = dPriv->numClipRects;
    imesa->pClipRects = dPriv->pClipRects;
    imesa->drawX = dPriv->x;
    imesa->drawY = dPriv->y;

    i830EmitDrawingRectangle( imesa );
    imesa->upload_cliprects = GL_TRUE;
 }

 void i830XMesaSetBackClipRects( i830ContextPtr imesa )
 {
    __DRIdrawablePrivate *dPriv = imesa->driDrawable;

    if (imesa->sarea->pf_enabled == 0 && dPriv->numBackClipRects == 0) {
       imesa->numClipRects = dPriv->numClipRects;
       imesa->pClipRects = dPriv->pClipRects;
       imesa->drawX = dPriv->x;
       imesa->drawY = dPriv->y;
    } else {
       imesa->numClipRects = dPriv->numBackClipRects;
       imesa->pClipRects = dPriv->pBackClipRects;
       imesa->drawX = dPriv->backX;
       imesa->drawY = dPriv->backY;
    }

    i830EmitDrawingRectangle( imesa );
    imesa->upload_cliprects = GL_TRUE;
 }

 static void i830XMesaWindowMoved( i830ContextPtr imesa )
 {
    switch (imesa->glCtx->Color._DrawDestMask) {
    case FRONT_LEFT_BIT:
       i830XMesaSetFrontClipRects( imesa );
       break;
    case BACK_LEFT_BIT:
       i830XMesaSetBackClipRects( imesa );
       break;
    default:
       /* glDrawBuffer(GL_NONE or GL_FRONT_AND_BACK): software fallback */
       i830XMesaSetFrontClipRects( imesa );
    }
 }

 GLboolean i830UnbindContext(__DRIcontextPrivate *driContextPriv)
 {
    i830ContextPtr imesa = (i830ContextPtr) driContextPriv->driverPrivate;
    if (imesa) {
       /* Might want to change this so texblend isn't always updated */
       imesa->dirty |= (I830_UPLOAD_CTX |
 		       I830_UPLOAD_BUFFERS |
 		       I830_UPLOAD_STIPPLE |
 		       I830_UPLOAD_TEXBLEND0 |
 		       I830_UPLOAD_TEXBLEND1);

       if (imesa->CurrentTexObj[0]) imesa->dirty |= I830_UPLOAD_TEX0;
       if (imesa->CurrentTexObj[1]) imesa->dirty |= I830_UPLOAD_TEX1;
    }
    return GL_TRUE;
 }

 GLboolean i830MakeCurrent(__DRIcontextPrivate *driContextPriv,
 			  __DRIdrawablePrivate *driDrawPriv,
 			  __DRIdrawablePrivate *driReadPriv)
 {

    if (driContextPriv) {
       i830ContextPtr imesa = (i830ContextPtr) driContextPriv->driverPrivate;

       if ( imesa->driDrawable != driDrawPriv ) {
 	 /* Shouldn't the readbuffer be stored also? */
 	 imesa->driDrawable = driDrawPriv;
 	 i830XMesaWindowMoved( imesa );
       }

       _mesa_make_current2(imesa->glCtx,
 			  (GLframebuffer *) driDrawPriv->driverPrivate,
 			  (GLframebuffer *) driReadPriv->driverPrivate);

       if (!imesa->glCtx->Viewport.Width)
 	 _mesa_set_viewport(imesa->glCtx, 0, 0,
 			    driDrawPriv->w, driDrawPriv->h);
    } else {
       _mesa_make_current(0,0);
    }

    return GL_TRUE;
 }

 void i830GetLock( i830ContextPtr imesa, GLuint flags )
 {
    __DRIdrawablePrivate *dPriv = imesa->driDrawable;
    __DRIscreenPrivate *sPriv = imesa->driScreen;
    I830SAREAPtr sarea = imesa->sarea;
    int me = imesa->hHWContext;
    unsigned   i;

    drmGetLock(imesa->driFd, imesa->hHWContext, flags);

    /* If the window moved, may need to set a new cliprect now.
     *
     * NOTE: This releases and regains the hw lock, so all state
     * checking must be done *after* this call:
     */
    DRI_VALIDATE_DRAWABLE_INFO( sPriv, dPriv);

    /* If we lost context, need to dump all registers to hardware.
     * Note that we don't care about 2d contexts, even if they perform
     * accelerated commands, so the DRI locking in the X server is even
     * more broken than usual.
     */

    if (sarea->ctxOwner != me) {
       imesa->upload_cliprects = GL_TRUE;
       imesa->dirty |= (I830_UPLOAD_CTX |
 		       I830_UPLOAD_BUFFERS |
 		       I830_UPLOAD_STIPPLE);

       if(imesa->CurrentTexObj[0]) imesa->dirty |= I830_UPLOAD_TEX0;
       if(imesa->CurrentTexObj[1]) imesa->dirty |= I830_UPLOAD_TEX1;
       if(imesa->TexBlendWordsUsed[0]) imesa->dirty |= I830_UPLOAD_TEXBLEND0;
       if(imesa->TexBlendWordsUsed[1]) imesa->dirty |= I830_UPLOAD_TEXBLEND1;

       sarea->perf_boxes = imesa->perf_boxes | I830_BOX_LOST_CONTEXT;
       sarea->ctxOwner = me;
    }

    /* Shared texture managment - if another client has played with
     * texture space, figure out which if any of our textures have been
     * ejected, and update our global LRU.
     */

    for ( i = 0 ; i < imesa->nr_heaps ; i++ ) {
       DRI_AGE_TEXTURES( imesa->texture_heaps[ i ] );
    }

    if (imesa->lastStamp != dPriv->lastStamp) {
       i830XMesaWindowMoved( imesa );
       imesa->lastStamp = dPriv->lastStamp;
    }

    sarea->last_quiescent = -1;  /* just kill it for now */
 }

 void i830SwapBuffers( __DRIdrawablePrivate *dPriv )
 {
    if (dPriv->driContextPriv && dPriv->driContextPriv->driverPrivate) {
       i830ContextPtr imesa;
       GLcontext *ctx;
       imesa = (i830ContextPtr) dPriv->driContextPriv->driverPrivate;
       ctx = imesa->glCtx;
       if (ctx->Visual.doubleBufferMode) {
 	 _mesa_notifySwapBuffers( ctx );  /* flush pending rendering comands */
 	 if ( 0 /*imesa->doPageFlip*/ ) { /* doPageFlip is never set !!! */
 	    i830PageFlip( dPriv );
 	 } else {
 	    i830CopyBuffer( dPriv );
 	 }
       }
    } else {
       /* XXX this shouldn't be an error but we can't handle it for now */
       _mesa_problem(NULL, "%s: drawable has no context!\n", __FUNCTION__);
    }
 }
	/**************************************************************************
	*
	* Copyright 1998-1999 Precision Insight, Inc., Cedar Park, Texas.
	* 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 PRECISION INSIGHT 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.
	*
	* **************************************************************************/
	/* $XFree86: xc/lib/GL/mesa/src/drv/i830/i830_context.c,v 1.9 2003/02/06 04:18:00 dawes Exp $ */

	/*
	* Authors:
	* Jeff Hartmann <jhartmann@2d3d.com>
	* Graeme Fisher <graeme@2d3d.co.za>
	* Abraham vd Merwe <abraham@2d3d.co.za>
	*
	* Heavily Based on I810 driver written by:
	* Keith Whitwell <keith@tungstengraphics.com>
	*/

	#include "glheader.h"
	#include "context.h"
	#include "matrix.h"
	#include "simple_list.h"
	#include "extensions.h"
	#include "imports.h"

	#include "swrast/swrast.h"
	#include "swrast_setup/swrast_setup.h"
	#include "tnl/tnl.h"
	#include "array_cache/acache.h"

	#include "tnl/t_pipeline.h"

	#include "i830_screen.h"
	#include "i830_dri.h"

	#include "i830_state.h"
	#include "i830_tex.h"
	#include "i830_span.h"
	#include "i830_tris.h"
	#include "i830_vb.h"
	#include "i830_ioctl.h"


	#include "utils.h"
	#ifndef I830_DEBUG
	int I830_DEBUG = (0);
	#endif

	/***************************************
	* Mesa's Driver Functions
	***************************************/

	#define DRIVER_DATE "20021115"

	static const GLubyte i830DDGetString( GLcontext ctx, GLenum name )
	{
	const char * chipset;
	static char buffer[128];

	switch (name) {
	case GL_VENDOR:
	switch (I830_CONTEXT(ctx)->i830Screen->deviceID) {
	case PCI_CHIP_845_G:
	return (GLubyte *)"2d3D, Inc";

	case PCI_CHIP_I830_M:
	return (GLubyte *)"VA Linux, Inc";

	case PCI_CHIP_I855_GM:
	case PCI_CHIP_I865_G:
	default:
	return (GLubyte *)"Tungsten Graphics, Inc";
	}
	break;

	case GL_RENDERER:
	switch (I830_CONTEXT(ctx)->i830Screen->deviceID) {
	case PCI_CHIP_845_G:
	chipset = "Intel(R) 845G"; break;
	case PCI_CHIP_I830_M:
	chipset = "Intel(R) 830M"; break;
	case PCI_CHIP_I855_GM:
	chipset = "Intel(R) 852GM/855GM"; break;
	case PCI_CHIP_I865_G:
	chipset = "Intel(R) 865G"; break;
	default:
	chipset = "Unknown Intel Chipset"; break;
	}

	(void) driGetRendererString( buffer, chipset, DRIVER_DATE, 0 );
	return (GLubyte *) buffer;

	default:
	return NULL;
	}
	}

	static void i830BufferSize(GLframebuffer *buffer,
	GLuint width, GLuint height)
	{
	GET_CURRENT_CONTEXT(ctx);
	i830ContextPtr imesa = I830_CONTEXT(ctx);
	/* Need to lock to make sure the driDrawable is uptodate. This
	* information is used to resize Mesa's software buffers, so it has
	* to be correct.
	*/
	LOCK_HARDWARE(imesa);
	*width = imesa->driDrawable->w;
	*height = imesa->driDrawable->h;
	UNLOCK_HARDWARE(imesa);
	}


	/* Extension strings exported by the i830 driver.
	*/
	static const char * const card_extensions[] =
	{
	"GL_ARB_multisample",
	"GL_ARB_multitexture",
	"GL_ARB_texture_border_clamp",
	"GL_ARB_texture_compression",
	"GL_ARB_texture_env_add",
	"GL_ARB_texture_env_combine",
	"GL_ARB_texture_env_dot3",
	"GL_ARB_texture_mirrored_repeat",
	"GL_EXT_blend_color",
	"GL_EXT_blend_func_separate",
	"GL_EXT_blend_minmax",
	"GL_EXT_blend_subtract",
	"GL_EXT_fog_coord",
	"GL_EXT_secondary_color",
	"GL_EXT_stencil_wrap",
	"GL_EXT_texture_edge_clamp",
	"GL_EXT_texture_env_add",
	"GL_EXT_texture_env_combine",
	"GL_EXT_texture_env_dot3",
	"GL_EXT_texture_filter_anisotropic",
	"GL_EXT_texture_lod_bias",
	"GL_IBM_texture_mirrored_repeat",
	"GL_INGR_blend_func_separate",
	"GL_MESA_ycbcr_texture",
	"GL_NV_texture_rectangle",
	"GL_SGIS_generate_mipmap",
	"GL_SGIS_texture_border_clamp",
	"GL_SGIS_texture_edge_clamp",
	NULL
	};


	extern const struct tnl_pipeline_stage _i830_render_stage;

	static const struct tnl_pipeline_stage *i830_pipeline[] = {
	&_tnl_vertex_transform_stage,
	&_tnl_normal_transform_stage,
	&_tnl_lighting_stage,
	&_tnl_fog_coordinate_stage,
	&_tnl_texgen_stage,
	&_tnl_texture_transform_stage,
	/* REMOVE: point attenuation stage */
	#if 1
	&_i830_render_stage, /* ADD: unclipped rastersetup-to-dma */
	#endif
	&_tnl_render_stage,
	0,
	};


	static const struct dri_debug_control debug_control[] =
	{
	{ "fall", DEBUG_FALLBACKS },
	{ "tex", DEBUG_TEXTURE },
	{ "ioctl", DEBUG_IOCTL },
	{ "prim", DEBUG_PRIMS },
	{ "vert", DEBUG_VERTS },
	{ "state", DEBUG_STATE },
	{ "verb", DEBUG_VERBOSE },
	{ "dri", DEBUG_DRI },
	{ "dma", DEBUG_DMA },
	{ "san", DEBUG_SANITY },
	{ "sync", DEBUG_SYNC },
	{ "sleep", DEBUG_SLEEP },
	{ NULL, 0 }
	};


	GLboolean i830CreateContext( const __GLcontextModes *mesaVis,
	__DRIcontextPrivate *driContextPriv,
	void *sharedContextPrivate)
	{
	GLcontext ctx , shareCtx;
	i830ContextPtr imesa;
	__DRIscreenPrivate *sPriv = driContextPriv->driScreenPriv;
	i830ScreenPrivate screen = (i830ScreenPrivate )sPriv->private;
	I830SAREAPtr saPriv=(I830SAREAPtr)
	(((GLubyte *)sPriv->pSAREA)+screen->sarea_priv_offset);

	/* Allocate i830 context */
	imesa = (i830ContextPtr) CALLOC_STRUCT(i830_context_t);
	if (!imesa) return GL_FALSE;

	/* Allocate the Mesa context */
	if (sharedContextPrivate)
	shareCtx = ((i830ContextPtr) sharedContextPrivate)->glCtx;
	else
	shareCtx = NULL;
	imesa->glCtx = _mesa_create_context(mesaVis, shareCtx, (void*) imesa, GL_TRUE);
	if (!imesa->glCtx) {
	FREE(imesa);
	return GL_FALSE;
	}
	driContextPriv->driverPrivate = imesa;


	imesa->i830Screen = screen;
	imesa->driScreen = sPriv;
	imesa->sarea = saPriv;
	imesa->glBuffer = NULL;


	(void) memset( imesa->texture_heaps, 0, sizeof( imesa->texture_heaps ) );
	make_empty_list( & imesa->swapped );

	imesa->nr_heaps = 1;
	imesa->texture_heaps[0] = driCreateTextureHeap( 0, imesa,
	screen->textureSize,
	12,
	I830_NR_TEX_REGIONS,
	imesa->sarea->texList,
	& imesa->sarea->texAge,
	& imesa->swapped,
	sizeof( struct i830_texture_object_t ),
	(destroy_texture_object_t *) i830DestroyTexObj );


	/* Set the maximum texture size small enough that we can guarantee
	* that both texture units can bind a maximal texture and have them
	* in memory at once.
	*/

	ctx = imesa->glCtx;
	ctx->Const.MaxTextureUnits = 2;

	/* FIXME: driCalcualteMaxTextureLevels assumes that mipmaps are tightly
	* FIXME: packed, but they're not in Intel graphics hardware.
	*/
	driCalculateMaxTextureLevels( imesa->texture_heaps,
	imesa->nr_heaps,
	& ctx->Const,
	4,
	11, /* max 2D texture size is 2048x2048 */
	0, /* 3D textures unsupported */
	0, /* cube textures unsupported. */
	0, /* texture rectangles unsupported. */
	12,
	GL_FALSE );

	ctx->Const.MaxTextureMaxAnisotropy = 2.0;

	ctx->Const.MinLineWidth = 1.0;
	ctx->Const.MinLineWidthAA = 1.0;
	ctx->Const.MaxLineWidth = 3.0;
	ctx->Const.MaxLineWidthAA = 3.0;
	ctx->Const.LineWidthGranularity = 1.0;

	ctx->Const.MinPointSize = 1.0;
	ctx->Const.MinPointSizeAA = 1.0;
	ctx->Const.MaxPointSize = 255.0;
	ctx->Const.MaxPointSizeAA = 3.0;
	ctx->Const.PointSizeGranularity = 1.0;

	ctx->Driver.GetBufferSize = i830BufferSize;
	ctx->Driver.ResizeBuffers = _swrast_alloc_buffers;
	ctx->Driver.GetString = i830DDGetString;

	/* Who owns who? */
	ctx->DriverCtx = (void *) imesa;
	imesa->glCtx = ctx;

	/* Initialize the software rasterizer and helper modules. */
	_swrast_CreateContext( ctx );
	_ac_CreateContext( ctx );
	_tnl_CreateContext( ctx );
	_swsetup_CreateContext( ctx );

	/* Install the customized pipeline: */
	_tnl_destroy_pipeline( ctx );
	_tnl_install_pipeline( ctx, i830_pipeline );

	/* Configure swrast to match hardware characteristics: */
	_swrast_allow_pixel_fog( ctx, GL_FALSE );
	_swrast_allow_vertex_fog( ctx, GL_TRUE );

	/* Dri stuff */
	imesa->hHWContext = driContextPriv->hHWContext;
	imesa->driFd = sPriv->fd;
	imesa->driHwLock = &sPriv->pSAREA->lock;
	imesa->vertex_format = 0;

	imesa->hw_stencil = mesaVis->stencilBits && mesaVis->depthBits == 24;

	switch(mesaVis->depthBits) {
	case 16:
	imesa->depth_scale = 1.0/0xffff;
	imesa->depth_clear_mask = ~0;
	imesa->ClearDepth = 0xffff;
	break;
	case 24:
	imesa->depth_scale = 1.0/0xffffff;
	imesa->depth_clear_mask = 0x00ffffff;
	imesa->stencil_clear_mask = 0xff000000;
	imesa->ClearDepth = 0x00ffffff;
	break;
	case 32: /* Not supported */
	default:
	break;
	}
	/* Completely disable stenciling for now, there are some serious issues
	* with stencil.
	*/
	#if 0
	imesa->hw_stencil = 0;
	#endif

	imesa->RenderIndex = ~0;
	imesa->dirty = ~0;
	imesa->upload_cliprects = GL_TRUE;

	imesa->CurrentTexObj[0] = 0;
	imesa->CurrentTexObj[1] = 0;

	imesa->do_irqs = (imesa->i830Screen->irq_active &&
	!getenv("I830_NO_IRQS"));

	_math_matrix_ctr (&imesa->ViewportMatrix);

	driInitExtensions( ctx, card_extensions, GL_TRUE );
	i830DDInitStateFuncs( ctx );
	i830DDInitTextureFuncs( ctx );
	i830InitTriFuncs (ctx);
	i830DDInitSpanFuncs( ctx );
	i830DDInitIoctlFuncs( ctx );
	i830InitVB (ctx);
	i830DDInitState (ctx);

	#if DO_DEBUG
	I830_DEBUG = driParseDebugString( getenv( "I830_DEBUG" ),
	debug_control );
	I830_DEBUG \|= driParseDebugString( getenv( "INTEL_DEBUG" ),
	debug_control );
	#endif

	if (getenv("I830_NO_RAST") \|\|
	getenv("INTEL_NO_RAST")) {
	fprintf(stderr, "disabling 3D rasterization\n");
	FALLBACK(imesa, I830_FALLBACK_USER, 1);
	}


	return GL_TRUE;
	}

	void i830DestroyContext(__DRIcontextPrivate *driContextPriv)
	{
	i830ContextPtr imesa = (i830ContextPtr) driContextPriv->driverPrivate;

	assert(imesa); /* should never be null */
	if (imesa) {
	GLboolean release_texture_heaps;


	release_texture_heaps = (imesa->glCtx->Shared->RefCount == 1);
	_swsetup_DestroyContext (imesa->glCtx);
	_tnl_DestroyContext (imesa->glCtx);
	_ac_DestroyContext (imesa->glCtx);
	_swrast_DestroyContext (imesa->glCtx);

	i830FreeVB (imesa->glCtx);

	/* free the Mesa context */
	imesa->glCtx->DriverCtx = NULL;
	_mesa_destroy_context(imesa->glCtx);

	if ( release_texture_heaps ) {
	/* This share group is about to go away, free our private
	* texture object data.
	*/
	int i;

	assert( is_empty_list( & imesa->swapped ) );

	for ( i = 0 ; i < imesa->nr_heaps ; i++ ) {
	driDestroyTextureHeap( imesa->texture_heaps[ i ] );
	imesa->texture_heaps[ i ] = NULL;
	}
	}

	Xfree (imesa);
	}
	}

	void i830XMesaSetFrontClipRects( i830ContextPtr imesa )
	{
	__DRIdrawablePrivate *dPriv = imesa->driDrawable;

	imesa->numClipRects = dPriv->numClipRects;
	imesa->pClipRects = dPriv->pClipRects;
	imesa->drawX = dPriv->x;
	imesa->drawY = dPriv->y;

	i830EmitDrawingRectangle( imesa );
	imesa->upload_cliprects = GL_TRUE;
	}

	void i830XMesaSetBackClipRects( i830ContextPtr imesa )
	{
	__DRIdrawablePrivate *dPriv = imesa->driDrawable;

	if (imesa->sarea->pf_enabled == 0 && dPriv->numBackClipRects == 0) {
	imesa->numClipRects = dPriv->numClipRects;
	imesa->pClipRects = dPriv->pClipRects;
	imesa->drawX = dPriv->x;
	imesa->drawY = dPriv->y;
	} else {
	imesa->numClipRects = dPriv->numBackClipRects;
	imesa->pClipRects = dPriv->pBackClipRects;
	imesa->drawX = dPriv->backX;
	imesa->drawY = dPriv->backY;
	}

	i830EmitDrawingRectangle( imesa );
	imesa->upload_cliprects = GL_TRUE;
	}

	static void i830XMesaWindowMoved( i830ContextPtr imesa )
	{
	switch (imesa->glCtx->Color._DrawDestMask) {
	case FRONT_LEFT_BIT:
	i830XMesaSetFrontClipRects( imesa );
	break;
	case BACK_LEFT_BIT:
	i830XMesaSetBackClipRects( imesa );
	break;
	default:
	/* glDrawBuffer(GL_NONE or GL_FRONT_AND_BACK): software fallback */
	i830XMesaSetFrontClipRects( imesa );
	}
	}

	GLboolean i830UnbindContext(__DRIcontextPrivate *driContextPriv)
	{
	i830ContextPtr imesa = (i830ContextPtr) driContextPriv->driverPrivate;
	if (imesa) {
	/* Might want to change this so texblend isn't always updated */
	imesa->dirty \|= (I830_UPLOAD_CTX \|
	I830_UPLOAD_BUFFERS \|
	I830_UPLOAD_STIPPLE \|
	I830_UPLOAD_TEXBLEND0 \|
	I830_UPLOAD_TEXBLEND1);

	if (imesa->CurrentTexObj[0]) imesa->dirty \|= I830_UPLOAD_TEX0;
	if (imesa->CurrentTexObj[1]) imesa->dirty \|= I830_UPLOAD_TEX1;
	}
	return GL_TRUE;
	}

	GLboolean i830MakeCurrent(__DRIcontextPrivate *driContextPriv,
	__DRIdrawablePrivate *driDrawPriv,
	__DRIdrawablePrivate *driReadPriv)
	{

	if (driContextPriv) {
	i830ContextPtr imesa = (i830ContextPtr) driContextPriv->driverPrivate;

	if ( imesa->driDrawable != driDrawPriv ) {
	/* Shouldn't the readbuffer be stored also? */
	imesa->driDrawable = driDrawPriv;
	i830XMesaWindowMoved( imesa );
	}

	_mesa_make_current2(imesa->glCtx,
	(GLframebuffer *) driDrawPriv->driverPrivate,
	(GLframebuffer *) driReadPriv->driverPrivate);

	if (!imesa->glCtx->Viewport.Width)
	_mesa_set_viewport(imesa->glCtx, 0, 0,
	driDrawPriv->w, driDrawPriv->h);
	} else {
	_mesa_make_current(0,0);
	}

	return GL_TRUE;
	}

	void i830GetLock( i830ContextPtr imesa, GLuint flags )
	{
	__DRIdrawablePrivate *dPriv = imesa->driDrawable;
	__DRIscreenPrivate *sPriv = imesa->driScreen;
	I830SAREAPtr sarea = imesa->sarea;
	int me = imesa->hHWContext;
	unsigned i;

	drmGetLock(imesa->driFd, imesa->hHWContext, flags);

	/* If the window moved, may need to set a new cliprect now.
	*
	* NOTE: This releases and regains the hw lock, so all state
	* checking must be done after this call:
	*/
	DRI_VALIDATE_DRAWABLE_INFO( sPriv, dPriv);

	/* If we lost context, need to dump all registers to hardware.
	* Note that we don't care about 2d contexts, even if they perform
	* accelerated commands, so the DRI locking in the X server is even
	* more broken than usual.
	*/

	if (sarea->ctxOwner != me) {
	imesa->upload_cliprects = GL_TRUE;
	imesa->dirty \|= (I830_UPLOAD_CTX \|
	I830_UPLOAD_BUFFERS \|
	I830_UPLOAD_STIPPLE);

	if(imesa->CurrentTexObj[0]) imesa->dirty \|= I830_UPLOAD_TEX0;
	if(imesa->CurrentTexObj[1]) imesa->dirty \|= I830_UPLOAD_TEX1;
	if(imesa->TexBlendWordsUsed[0]) imesa->dirty \|= I830_UPLOAD_TEXBLEND0;
	if(imesa->TexBlendWordsUsed[1]) imesa->dirty \|= I830_UPLOAD_TEXBLEND1;

	sarea->perf_boxes = imesa->perf_boxes \| I830_BOX_LOST_CONTEXT;
	sarea->ctxOwner = me;
	}

	/* Shared texture managment - if another client has played with
	* texture space, figure out which if any of our textures have been
	* ejected, and update our global LRU.
	*/

	for ( i = 0 ; i < imesa->nr_heaps ; i++ ) {
	DRI_AGE_TEXTURES( imesa->texture_heaps[ i ] );
	}

	if (imesa->lastStamp != dPriv->lastStamp) {
	i830XMesaWindowMoved( imesa );
	imesa->lastStamp = dPriv->lastStamp;
	}

	sarea->last_quiescent = -1; /* just kill it for now */
	}

	void i830SwapBuffers( __DRIdrawablePrivate *dPriv )
	{
	if (dPriv->driContextPriv && dPriv->driContextPriv->driverPrivate) {
	i830ContextPtr imesa;
	GLcontext *ctx;
	imesa = (i830ContextPtr) dPriv->driContextPriv->driverPrivate;
	ctx = imesa->glCtx;
	if (ctx->Visual.doubleBufferMode) {
	_mesa_notifySwapBuffers( ctx ); /* flush pending rendering comands */
	if ( 0 /imesa->doPageFlip/ ) { /* doPageFlip is never set !!! */
	i830PageFlip( dPriv );
	} else {
	i830CopyBuffer( dPriv );
	}
	}
	} else {
	/* XXX this shouldn't be an error but we can't handle it for now */
	_mesa_problem(NULL, "%s: drawable has no context!\n", __FUNCTION__);
	}
	}