dri: Remove DRI1 fields from DRI structs
[mesa.git] / src / mesa / drivers / dri / common / dri_util.c
index bf8cf6eec07e312529346b5a6790293d33771943..e42bc84cca394d726d284854c502f1d942b470b9 100644 (file)
@@ -50,27 +50,6 @@ typedef GLboolean ( * PFNGLXGETMSCRATEOMLPROC) (__DRIdrawable *drawable, int32_t
 static void dri_get_drawable(__DRIdrawable *pdp);
 static void dri_put_drawable(__DRIdrawable *pdp);
 
-/**
- * This is just a token extension used to signal that the driver
- * supports setting a read drawable.
- */
-const __DRIextension driReadDrawableExtension = {
-    __DRI_READ_DRAWABLE, __DRI_READ_DRAWABLE_VERSION
-};
-
-GLint
-driIntersectArea( drm_clip_rect_t rect1, drm_clip_rect_t rect2 )
-{
-   if (rect2.x1 > rect1.x1) rect1.x1 = rect2.x1;
-   if (rect2.x2 < rect1.x2) rect1.x2 = rect2.x2;
-   if (rect2.y1 > rect1.y1) rect1.y1 = rect2.y1;
-   if (rect2.y2 < rect1.y2) rect1.y2 = rect2.y2;
-
-   if (rect1.x1 > rect1.x2 || rect1.y1 > rect1.y2) return 0;
-
-   return (rect1.x2 - rect1.x1) * (rect1.y2 - rect1.y1);
-}
-
 /*****************************************************************/
 /** \name Context (un)binding functions                          */
 /*****************************************************************/
@@ -174,293 +153,10 @@ static int driBindContext(__DRIcontext *pcp,
        dri_get_drawable(prp);
     }
 
-    /*
-    ** Now that we have a context associated with this drawable, we can
-    ** initialize the drawable information if has not been done before.
-    */
-
-    if (!psp->dri2.enabled) {
-       if (pdp && !pdp->pStamp) {
-           DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
-           __driUtilUpdateDrawableInfo(pdp);
-           DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
-       }
-       if (prp && pdp != prp && !prp->pStamp) {
-           DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
-           __driUtilUpdateDrawableInfo(prp);
-           DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
-        }
-    }
-
     /* Call device-specific MakeCurrent */
     return (*psp->DriverAPI.MakeCurrent)(pcp, pdp, prp);
 }
 
-/*@}*/
-
-
-/*****************************************************************/
-/** \name Drawable handling functions                            */
-/*****************************************************************/
-/*@{*/
-
-/**
- * Update private drawable information.
- *
- * \param pdp pointer to the private drawable information to update.
- * 
- * This function basically updates the __DRIdrawable struct's
- * cliprect information by calling \c __DRIinterfaceMethods::getDrawableInfo.
- * This is usually called by the DRI_VALIDATE_DRAWABLE_INFO macro which
- * compares the __DRIdrwablePrivate pStamp and lastStamp values.  If
- * the values are different that means we have to update the clipping
- * info.
- */
-void
-__driUtilUpdateDrawableInfo(__DRIdrawable *pdp)
-{
-    __DRIscreen *psp = pdp->driScreenPriv;
-    __DRIcontext *pcp = pdp->driContextPriv;
-    
-    if (!pcp 
-       || ((pdp != pcp->driDrawablePriv) && (pdp != pcp->driReadablePriv))) {
-       /* ERROR!!! 
-        * ...but we must ignore it. There can be many contexts bound to a
-        * drawable.
-        */
-    }
-
-    if (pdp->pClipRects) {
-       free(pdp->pClipRects); 
-       pdp->pClipRects = NULL;
-    }
-
-    if (pdp->pBackClipRects) {
-       free(pdp->pBackClipRects); 
-       pdp->pBackClipRects = NULL;
-    }
-
-    DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
-
-    if (! (*psp->getDrawableInfo->getDrawableInfo)(pdp,
-                         &pdp->index, &pdp->lastStamp,
-                         &pdp->x, &pdp->y, &pdp->w, &pdp->h,
-                         &pdp->numClipRects, &pdp->pClipRects,
-                         &pdp->backX,
-                         &pdp->backY,
-                         &pdp->numBackClipRects,
-                         &pdp->pBackClipRects,
-                         pdp->loaderPrivate)) {
-       /* Error -- eg the window may have been destroyed.  Keep going
-        * with no cliprects.
-        */
-        pdp->pStamp = &pdp->lastStamp; /* prevent endless loop */
-       pdp->numClipRects = 0;
-       pdp->pClipRects = NULL;
-       pdp->numBackClipRects = 0;
-       pdp->pBackClipRects = NULL;
-    }
-    else
-       pdp->pStamp = &(psp->pSAREA->drawableTable[pdp->index].stamp);
-
-    DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
-}
-
-/*@}*/
-
-/*****************************************************************/
-/** \name GLX callbacks                                          */
-/*****************************************************************/
-/*@{*/
-
-static void driReportDamage(__DRIdrawable *pdp,
-                           struct drm_clip_rect *pClipRects, int numClipRects)
-{
-    __DRIscreen *psp = pdp->driScreenPriv;
-
-    /* Check that we actually have the new damage report method */
-    if (psp->damage) {
-       /* Report the damage.  Currently, all our drivers draw
-        * directly to the front buffer, so we report the damage there
-        * rather than to the backing storein (if any).
-        */
-       (*psp->damage->reportDamage)(pdp,
-                                    pdp->x, pdp->y,
-                                    pClipRects, numClipRects,
-                                    GL_TRUE, pdp->loaderPrivate);
-    }
-}
-
-
-/**
- * Swap buffers.
- *
- * \param drawablePrivate opaque pointer to the per-drawable private info.
- * 
- * \internal
- * This function calls __DRIdrawable::swapBuffers.
- * 
- * Is called directly from glXSwapBuffers().
- */
-static void driSwapBuffers(__DRIdrawable *dPriv)
-{
-    __DRIscreen *psp = dPriv->driScreenPriv;
-    drm_clip_rect_t *rects;
-    int i;
-
-    psp->DriverAPI.SwapBuffers(dPriv);
-
-    if (!dPriv->numClipRects)
-        return;
-
-    rects = malloc(sizeof(*rects) * dPriv->numClipRects);
-
-    if (!rects)
-        return;
-
-    for (i = 0; i < dPriv->numClipRects; i++) {
-        rects[i].x1 = dPriv->pClipRects[i].x1 - dPriv->x;
-        rects[i].y1 = dPriv->pClipRects[i].y1 - dPriv->y;
-        rects[i].x2 = dPriv->pClipRects[i].x2 - dPriv->x;
-        rects[i].y2 = dPriv->pClipRects[i].y2 - dPriv->y;
-    }
-
-    driReportDamage(dPriv, rects, dPriv->numClipRects);
-    free(rects);
-}
-
-static int driDrawableGetMSC( __DRIscreen *sPriv, __DRIdrawable *dPriv,
-                             int64_t *msc )
-{
-    return sPriv->DriverAPI.GetDrawableMSC(sPriv, dPriv, msc);
-}
-
-
-static int driWaitForMSC(__DRIdrawable *dPriv, int64_t target_msc,
-                        int64_t divisor, int64_t remainder,
-                        int64_t * msc, int64_t * sbc)
-{
-    __DRIswapInfo  sInfo;
-    int  status;
-
-    status = dPriv->driScreenPriv->DriverAPI.WaitForMSC( dPriv, target_msc,
-                                                         divisor, remainder,
-                                                         msc );
-
-    /* GetSwapInfo() may not be provided by the driver if GLX_SGI_video_sync
-     * is supported but GLX_OML_sync_control is not.  Therefore, don't return
-     * an error value if GetSwapInfo() is not implemented.
-    */
-    if ( status == 0
-         && dPriv->driScreenPriv->DriverAPI.GetSwapInfo ) {
-        status = dPriv->driScreenPriv->DriverAPI.GetSwapInfo( dPriv, & sInfo );
-        *sbc = sInfo.swap_count;
-    }
-
-    return status;
-}
-
-
-const __DRImediaStreamCounterExtension driMediaStreamCounterExtension = {
-    { __DRI_MEDIA_STREAM_COUNTER, __DRI_MEDIA_STREAM_COUNTER_VERSION },
-    driWaitForMSC,
-    driDrawableGetMSC,
-};
-
-
-static void driCopySubBuffer(__DRIdrawable *dPriv,
-                             int x, int y, int w, int h)
-{
-    drm_clip_rect_t rect;
-
-    rect.x1 = x;
-    rect.y1 = dPriv->h - y - h;
-    rect.x2 = x + w;
-    rect.y2 = rect.y1 + h;
-    driReportDamage(dPriv, &rect, 1);
-
-    dPriv->driScreenPriv->DriverAPI.CopySubBuffer(dPriv, x, y, w, h);
-}
-
-const __DRIcopySubBufferExtension driCopySubBufferExtension = {
-    { __DRI_COPY_SUB_BUFFER, __DRI_COPY_SUB_BUFFER_VERSION },
-    driCopySubBuffer
-};
-
-static void driSetSwapInterval(__DRIdrawable *dPriv, unsigned int interval)
-{
-    dPriv->swap_interval = interval;
-}
-
-static unsigned int driGetSwapInterval(__DRIdrawable *dPriv)
-{
-    return dPriv->swap_interval;
-}
-
-const __DRIswapControlExtension driSwapControlExtension = {
-    { __DRI_SWAP_CONTROL, __DRI_SWAP_CONTROL_VERSION },
-    driSetSwapInterval,
-    driGetSwapInterval
-};
-
-
-/**
- * This is called via __DRIscreenRec's createNewDrawable pointer.
- */
-static __DRIdrawable *
-driCreateNewDrawable(__DRIscreen *psp, const __DRIconfig *config,
-                    drm_drawable_t hwDrawable, int renderType,
-                    const int *attrs, void *data)
-{
-    __DRIdrawable *pdp;
-
-    /* Since pbuffers are not yet supported, no drawable attributes are
-     * supported either.
-     */
-    (void) attrs;
-
-    pdp = malloc(sizeof *pdp);
-    if (!pdp) {
-       return NULL;
-    }
-
-    pdp->driContextPriv = NULL;
-    pdp->loaderPrivate = data;
-    pdp->hHWDrawable = hwDrawable;
-    pdp->refcount = 1;
-    pdp->pStamp = NULL;
-    pdp->lastStamp = 0;
-    pdp->index = 0;
-    pdp->x = 0;
-    pdp->y = 0;
-    pdp->w = 0;
-    pdp->h = 0;
-    pdp->numClipRects = 0;
-    pdp->numBackClipRects = 0;
-    pdp->pClipRects = NULL;
-    pdp->pBackClipRects = NULL;
-    pdp->vblSeq = 0;
-    pdp->vblFlags = 0;
-
-    pdp->driScreenPriv = psp;
-
-    if (!(*psp->DriverAPI.CreateBuffer)(psp, pdp, &config->modes, 0)) {
-       free(pdp);
-       return NULL;
-    }
-
-    pdp->msc_base = 0;
-
-    /* This special default value is replaced with the configured
-     * default value when the drawable is first bound to a direct
-     * rendering context. 
-     */
-    pdp->swap_interval = (unsigned)-1;
-
-    return pdp;
-}
-
-
 static __DRIdrawable *
 dri2CreateNewDrawable(__DRIscreen *screen,
                      const __DRIconfig *config,
@@ -468,12 +164,23 @@ dri2CreateNewDrawable(__DRIscreen *screen,
 {
     __DRIdrawable *pdraw;
 
-    pdraw = driCreateNewDrawable(screen, config, 0, 0, NULL, loaderPrivate);
+    pdraw = malloc(sizeof *pdraw);
     if (!pdraw)
-       return NULL;
+       return NULL;
 
-    pdraw->pClipRects = &pdraw->dri2.clipRect;
-    pdraw->pBackClipRects = &pdraw->dri2.clipRect;
+    pdraw->driContextPriv = NULL;
+    pdraw->loaderPrivate = loaderPrivate;
+    pdraw->refcount = 1;
+    pdraw->pStamp = NULL;
+    pdraw->lastStamp = 0;
+    pdraw->w = 0;
+    pdraw->h = 0;
+    pdraw->driScreenPriv = screen;
+
+    if (!(*screen->DriverAPI.CreateBuffer)(screen, pdraw, &config->modes, 0)) {
+       free(pdraw);
+       return NULL;
+    }
 
     pdraw->pStamp = &pdraw->dri2.stamp;
     *pdraw->pStamp = pdraw->lastStamp + 1;
@@ -481,6 +188,22 @@ dri2CreateNewDrawable(__DRIscreen *screen,
     return pdraw;
 }
 
+static __DRIbuffer *
+dri2AllocateBuffer(__DRIscreen *screen,
+                  unsigned int attachment, unsigned int format,
+                  int width, int height)
+{
+    return (*screen->DriverAPI.AllocateBuffer)(screen, attachment, format,
+                                              width, height);
+}
+
+static void
+dri2ReleaseBuffer(__DRIscreen *screen, __DRIbuffer *buffer)
+{
+   (*screen->DriverAPI.ReleaseBuffer)(screen, buffer);
+}
+
+
 static int
 dri2ConfigQueryb(__DRIscreen *screen, const char *var, GLboolean *val)
 {
@@ -532,14 +255,6 @@ static void dri_put_drawable(__DRIdrawable *pdp)
 
        psp = pdp->driScreenPriv;
         (*psp->DriverAPI.DestroyBuffer)(pdp);
-       if (pdp->pClipRects && pdp->pClipRects != &pdp->dri2.clipRect) {
-           free(pdp->pClipRects);
-           pdp->pClipRects = NULL;
-       }
-       if (pdp->pBackClipRects && pdp->pClipRects != &pdp->dri2.clipRect) {
-           free(pdp->pBackClipRects);
-           pdp->pBackClipRects = NULL;
-       }
        free(pdp);
     }
 }
@@ -574,54 +289,6 @@ driDestroyContext(__DRIcontext *pcp)
     }
 }
 
-
-/**
- * Create the per-drawable private driver information.
- * 
- * \param render_type   Type of rendering target.  \c GLX_RGBA is the only
- *                      type likely to ever be supported for direct-rendering.
- * \param shared        Context with which to share textures, etc. or NULL
- *
- * \returns An opaque pointer to the per-context private information on
- *          success, or \c NULL on failure.
- * 
- * \internal
- * This function allocates and fills a __DRIcontextRec structure.  It
- * performs some device independent initialization and passes all the
- * relevent information to __DriverAPIRec::CreateContext to create the
- * context.
- *
- */
-static __DRIcontext *
-driCreateNewContext(__DRIscreen *psp, const __DRIconfig *config,
-                   int render_type, __DRIcontext *shared, 
-                   drm_context_t hwContext, void *data)
-{
-    __DRIcontext *pcp;
-    void * const shareCtx = (shared != NULL) ? shared->driverPrivate : NULL;
-
-    pcp = malloc(sizeof *pcp);
-    if (!pcp)
-       return NULL;
-
-    pcp->driScreenPriv = psp;
-    pcp->driDrawablePriv = NULL;
-    pcp->loaderPrivate = data;
-    
-    pcp->dri2.draw_stamp = 0;
-    pcp->dri2.read_stamp = 0;
-
-    pcp->hHWContext = hwContext;
-
-    if ( !(*psp->DriverAPI.CreateContext)(API_OPENGL,
-                                         &config->modes, pcp, shareCtx) ) {
-        free(pcp);
-        return NULL;
-    }
-
-    return pcp;
-}
-
 static unsigned int
 dri2GetAPIMask(__DRIscreen *screen)
 {
@@ -684,6 +351,9 @@ dri2CreateNewContext(__DRIscreen *screen, const __DRIconfig *config,
 static int
 driCopyContext(__DRIcontext *dest, __DRIcontext *src, unsigned long mask)
 {
+    (void) dest;
+    (void) src;
+    (void) mask;
     return GL_FALSE;
 }
 
@@ -715,14 +385,8 @@ static void driDestroyScreen(__DRIscreen *psp)
        if (psp->DriverAPI.DestroyScreen)
            (*psp->DriverAPI.DestroyScreen)(psp);
 
-       if (!psp->dri2.enabled) {
-          (void)drmUnmap((drmAddress)psp->pSAREA, SAREA_MAX);
-          (void)drmUnmap((drmAddress)psp->pFB, psp->fbSize);
-          (void)drmCloseOnce(psp->fd);
-       } else {
-          driDestroyOptionCache(&psp->optionCache);
-          driDestroyOptionInfo(&psp->optionInfo);
-       }
+       driDestroyOptionCache(&psp->optionCache);
+       driDestroyOptionInfo(&psp->optionInfo);
 
        free(psp);
     }
@@ -735,12 +399,6 @@ setupLoaderExtensions(__DRIscreen *psp,
     int i;
 
     for (i = 0; extensions[i]; i++) {
-       if (strcmp(extensions[i]->name, __DRI_GET_DRAWABLE_INFO) == 0)
-           psp->getDrawableInfo = (__DRIgetDrawableInfoExtension *) extensions[i];
-       if (strcmp(extensions[i]->name, __DRI_DAMAGE) == 0)
-           psp->damage = (__DRIdamageExtension *) extensions[i];
-       if (strcmp(extensions[i]->name, __DRI_SYSTEM_TIME) == 0)
-           psp->systemTime = (__DRIsystemTimeExtension *) extensions[i];
        if (strcmp(extensions[i]->name, __DRI_DRI2_LOADER) == 0)
            psp->dri2.loader = (__DRIdri2LoaderExtension *) extensions[i];
        if (strcmp(extensions[i]->name, __DRI_IMAGE_LOOKUP) == 0)
@@ -750,95 +408,6 @@ setupLoaderExtensions(__DRIscreen *psp,
     }
 }
 
-/**
- * This is the bootstrap function for the driver.  libGL supplies all of the
- * requisite information about the system, and the driver initializes itself.
- * This routine also fills in the linked list pointed to by \c driver_modes
- * with the \c struct gl_config that the driver can support for windows or
- * pbuffers.
- *
- * For legacy DRI.
- * 
- * \param scrn  Index of the screen
- * \param ddx_version Version of the 2D DDX.  This may not be meaningful for
- *                    all drivers.
- * \param dri_version Version of the "server-side" DRI.
- * \param drm_version Version of the kernel DRM.
- * \param frame_buffer Data describing the location and layout of the
- *                     framebuffer.
- * \param pSAREA       Pointer to the SAREA.
- * \param fd           Device handle for the DRM.
- * \param extensions   ??
- * \param driver_modes  Returns modes suppoted by the driver
- * \param loaderPrivate  ??
- * 
- * \note There is no need to check the minimum API version in this
- * function.  Since the name of this function is versioned, it is
- * impossible for a loader that is too old to even load this driver.
- */
-static __DRIscreen *
-driCreateNewScreen(int scrn,
-                  const __DRIversion *ddx_version,
-                  const __DRIversion *dri_version,
-                  const __DRIversion *drm_version,
-                  const __DRIframebuffer *frame_buffer,
-                  drmAddress pSAREA, int fd, 
-                  const __DRIextension **extensions,
-                  const __DRIconfig ***driver_modes,
-                  void *loaderPrivate)
-{
-    static const __DRIextension *emptyExtensionList[] = { NULL };
-    __DRIscreen *psp;
-
-    if (driDriverAPI.InitScreen == NULL)
-       return NULL;
-
-    psp = calloc(1, sizeof *psp);
-    if (!psp)
-       return NULL;
-
-    setupLoaderExtensions(psp, extensions);
-
-    /*
-    ** NOT_DONE: This is used by the X server to detect when the client
-    ** has died while holding the drawable lock.  The client sets the
-    ** drawable lock to this value.
-    */
-    psp->drawLockID = 1;
-
-    psp->drm_version = *drm_version;
-    psp->ddx_version = *ddx_version;
-    psp->dri_version = *dri_version;
-
-    psp->pSAREA = pSAREA;
-    psp->lock = (drmLock *) &psp->pSAREA->lock;
-
-    psp->pFB = frame_buffer->base;
-    psp->fbSize = frame_buffer->size;
-    psp->fbStride = frame_buffer->stride;
-    psp->fbWidth = frame_buffer->width;
-    psp->fbHeight = frame_buffer->height;
-    psp->devPrivSize = frame_buffer->dev_priv_size;
-    psp->pDevPriv = frame_buffer->dev_priv;
-    psp->fbBPP = psp->fbStride * 8 / frame_buffer->width;
-
-    psp->extensions = emptyExtensionList;
-    psp->fd = fd;
-    psp->myNum = scrn;
-    psp->dri2.enabled = GL_FALSE;
-
-    psp->DriverAPI = driDriverAPI;
-    psp->api_mask = (1 << __DRI_API_OPENGL);
-
-    *driver_modes = driDriverAPI.InitScreen(psp);
-    if (*driver_modes == NULL) {
-       free(psp);
-       return NULL;
-    }
-
-    return psp;
-}
-
 /**
  * DRI2
  */
@@ -907,7 +476,7 @@ const __DRIcoreExtension driCoreExtension = {
     driIndexConfigAttrib,
     NULL,
     driDestroyDrawable,
-    driSwapBuffers,
+    NULL,
     NULL,
     driCopyContext,
     driDestroyContext,
@@ -915,14 +484,6 @@ const __DRIcoreExtension driCoreExtension = {
     driUnbindContext
 };
 
-/** Legacy DRI interface */
-const __DRIlegacyExtension driLegacyExtension = {
-    { __DRI_LEGACY, __DRI_LEGACY_VERSION },
-    driCreateNewScreen,
-    driCreateNewDrawable,
-    driCreateNewContext,
-};
-
 /** DRI2 interface */
 const __DRIdri2Extension driDRI2Extension = {
     { __DRI_DRI2, __DRI_DRI2_VERSION },
@@ -930,7 +491,9 @@ const __DRIdri2Extension driDRI2Extension = {
     dri2CreateNewDrawable,
     dri2CreateNewContext,
     dri2GetAPIMask,
-    dri2CreateNewContextForAPI
+    dri2CreateNewContextForAPI,
+    dri2AllocateBuffer,
+    dri2ReleaseBuffer
 };
 
 const __DRI2configQueryExtension dri2ConfigQueryExtension = {
@@ -940,69 +503,6 @@ const __DRI2configQueryExtension dri2ConfigQueryExtension = {
    dri2ConfigQueryf,
 };
 
-/**
- * Calculate amount of swap interval used between GLX buffer swaps.
- * 
- * The usage value, on the range [0,max], is the fraction of total swap
- * interval time used between GLX buffer swaps is calculated.
- *
- *            \f$p = t_d / (i * t_r)\f$
- * 
- * Where \f$t_d\f$ is the time since the last GLX buffer swap, \f$i\f$ is the
- * swap interval (as set by \c glXSwapIntervalSGI), and \f$t_r\f$ time
- * required for a single vertical refresh period (as returned by \c
- * glXGetMscRateOML).
- * 
- * See the documentation for the GLX_MESA_swap_frame_usage extension for more
- * details.
- *
- * \param   dPriv  Pointer to the private drawable structure.
- * \return  If less than a single swap interval time period was required
- *          between GLX buffer swaps, a number greater than 0 and less than
- *          1.0 is returned.  If exactly one swap interval time period is
- *          required, 1.0 is returned, and if more than one is required then
- *          a number greater than 1.0 will be returned.
- *
- * \sa glXSwapIntervalSGI glXGetMscRateOML
- * 
- * \todo Instead of caching the \c glXGetMscRateOML function pointer, would it
- *       be possible to cache the sync rate?
- */
-float
-driCalculateSwapUsage( __DRIdrawable *dPriv, int64_t last_swap_ust,
-                      int64_t current_ust )
-{
-   int32_t   n;
-   int32_t   d;
-   int       interval;
-   float     usage = 1.0;
-   __DRIscreen *psp = dPriv->driScreenPriv;
-
-   if ( (*psp->systemTime->getMSCRate)(dPriv, &n, &d, dPriv->loaderPrivate) ) {
-      interval = (dPriv->swap_interval != 0) ? dPriv->swap_interval : 1;
-
-
-      /* We want to calculate
-       * (current_UST - last_swap_UST) / (interval * us_per_refresh).  We get
-       * current_UST by calling __glXGetUST.  last_swap_UST is stored in
-       * dPriv->swap_ust.  interval has already been calculated.
-       *
-       * The only tricky part is us_per_refresh.  us_per_refresh is
-       * 1000000 / MSC_rate.  We know the MSC_rate is n / d.  We can flip it
-       * around and say us_per_refresh = 1000000 * d / n.  Since this goes in
-       * the denominator of the final calculation, we calculate
-       * (interval * 1000000 * d) and move n into the numerator.
-       */
-
-      usage = (current_ust - last_swap_ust);
-      usage *= n;
-      usage /= (interval * d);
-      usage /= 1000000.0;
-   }
-   
-   return usage;
-}
-
 void
 dri2InvalidateDrawable(__DRIdrawable *drawable)
 {