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path: root/src/mesa/drivers/dri/i830/i830_context.c
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/**************************************************************************
 * 
 * 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 $ */

/**
 * \file i830_context.c
 * 
 * Heavily Based on I810 driver written by Keith Whitwell.
 *
 * \author Jeff Hartmann <jhartmann@2d3d.com>
 * \author Graeme Fisher <graeme@2d3d.co.za>
 * \author Abraham vd Merwe <abraham@2d3d.co.za>
 * \author 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 "drivers/common/driverfuncs.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_ioctl.h"


#include "utils.h"
#include "xmlpool.h" /* for symbolic values of enum-type options */
#ifndef I830_DEBUG
int I830_DEBUG = (0);
#endif

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

#define DRIVER_DATE                     "20040506"


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_crossbar",
   "GL_ARB_texture_env_dot3",
   "GL_ARB_texture_mirrored_repeat",
   "GL_EXT_blend_color",
   "GL_EXT_blend_equation_separate",
   "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_combine",
   "GL_EXT_texture_env_dot3",
   "GL_EXT_texture_filter_anisotropic",
   "GL_EXT_texture_lod_bias",
   "GL_EXT_texture_rectangle",
   "GL_NV_blend_square",
   "GL_MESA_ycbcr_texture",
   "GL_SGIS_generate_mipmap",
   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);
   struct dd_function_table functions;

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

   /* Init default driver functions then plug in our I830-specific functions
    * (the texture functions are especially important)
    */
   _mesa_init_driver_functions(&functions);
   i830InitIoctlFuncs(&functions);
   i830InitTextureFuncs(&functions);

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


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

   driParseConfigFiles (&imesa->optionCache, &screen->optionCache,
			screen->driScrnPriv->myNum, "i830");

   (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,
	    (unsigned *) & imesa->sarea->texAge, /* XXX shouldn't need cast! */
	    & 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 every texture unit can bind a maximal texture and have them
    * in memory at once.
    */

   ctx = imesa->glCtx;
   ctx->Const.MaxTextureUnits = driQueryOptioni(&imesa->optionCache, 
						"texture_units");
   ctx->Const.MaxTextureImageUnits = ctx->Const.MaxTextureUnits;
   ctx->Const.MaxTextureCoordUnits = ctx->Const.MaxTextureUnits;

   /* FIXME: driCalculateMaxTextureLevels 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 and T&L to match hardware characteristics: */
   _swrast_allow_pixel_fog( ctx, GL_FALSE );
   _swrast_allow_vertex_fog( ctx, GL_TRUE );
   _tnl_allow_pixel_fog( ctx, GL_FALSE );
   _tnl_allow_vertex_fog( ctx, GL_TRUE );

   /* Dri stuff */
   imesa->hHWContext = driContextPriv->hHWContext;
   imesa->driFd = sPriv->fd;
   /* drmLock ptr = &drm_hw_lock_t */
   imesa->driHwLock = (drmLock *) &sPriv->pSAREA->lock;
   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 );
   /* XXX these should really go right after _mesa_init_driver_functions() */
   i830DDInitStateFuncs( ctx );
   i830InitTriFuncs (ctx);
   i830DDInitSpanFuncs( 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);

      /* 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;

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

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

      FREE(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 DD_FRONT_LEFT_BIT:
      i830XMesaSetFrontClipRects( imesa );
      break;
   case DD_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;
   unsigned i;

   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 |
		       I830_UPLOAD_TEXBLEND2 |
		       I830_UPLOAD_TEXBLEND3);

      for ( i = 0 ; i < imesa->glCtx->Const.MaxTextureUnits ; i++ ) {
	 if (imesa->CurrentTexObj[i]) imesa->dirty |= I830_UPLOAD_TEX_N( i );
      }
   }
   return GL_TRUE;
}

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

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

      if ( imesa->driDrawable != driDrawPriv ) {
	 imesa->driDrawable = driDrawPriv;
	 i830XMesaWindowMoved( imesa );
	 imesa->mesa_drawable = driDrawPriv;
      }

       imesa->driReadable = driReadPriv;

      _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);

      for ( i = 0 ; i < imesa->glCtx->Const.MaxTextureUnits ; i++ ) {
	 if(imesa->CurrentTexObj[i]) imesa->dirty |= I830_UPLOAD_TEX_N( i );
	 if(imesa->TexBlendWordsUsed[i]) imesa->dirty |= I830_UPLOAD_TEXBLEND_N( i );
      }

      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__);
   }
}