1 files changed, 434 insertions, 434 deletions
diff --git a/mesalib/src/mesa/drivers/dri/common/vblank.c b/mesalib/src/mesa/drivers/dri/common/vblank.c
index 49b22a2dc..3b8136844 100644
--- a/mesalib/src/mesa/drivers/dri/common/vblank.c
+++ b/mesalib/src/mesa/drivers/dri/common/vblank.c
@@ -1,434 +1,434 @@
-/* -*- mode: c; c-basic-offset: 3 -*- */
-/*
- * (c) Copyright IBM Corporation 2002
- * 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
- * on 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
- * VA LINUX SYSTEM, IBM AND/OR THEIR 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.
- *
- * Authors:
- *    Ian Romanick <idr@us.ibm.com>
- */
-
-#include "main/glheader.h"
-#include "xf86drm.h"
-#include "main/mtypes.h"
-#include "main/macros.h"
-#include "main/dd.h"
-#include "vblank.h"
-#include "xmlpool.h"
-
-static unsigned int msc_to_vblank(__DRIdrawable * dPriv, int64_t msc)
-{
-   return (unsigned int)(msc - dPriv->msc_base + dPriv->vblank_base);
-}
-
-static int64_t vblank_to_msc(__DRIdrawable * dPriv, unsigned int vblank)
-{
-   return (int64_t)(vblank - dPriv->vblank_base + dPriv->msc_base);
-}
-
-
-/****************************************************************************/
-/**
- * Get the current MSC refresh counter.
- *
- * Stores the 64-bit count of vertical refreshes since some (arbitrary)
- * point in time in \c count.  Unless the value wraps around, which it
- * may, it will never decrease for a given drawable.
- *
- * \warning This function is called from \c glXGetVideoSyncSGI, which expects
- * a \c count of type \c unsigned (32-bit), and \c glXGetSyncValuesOML, which 
- * expects a \c count of type \c int64_t (signed 64-bit).  The kernel ioctl 
- * currently always returns a \c sequence of type \c unsigned.
- *
- * \param priv   Pointer to the DRI screen private struct.
- * \param dPriv  Pointer to the DRI drawable private struct
- * \param count  Storage to hold MSC counter.
- * \return       Zero is returned on success.  A negative errno value
- *               is returned on failure.
- */
-int driDrawableGetMSC32( __DRIscreen * priv,
-			 __DRIdrawable * dPriv,
-			 int64_t * count)
-{
-   drmVBlank vbl;
-   int ret;
-
-   /* Don't wait for anything.  Just get the current refresh count. */
-
-   vbl.request.type = DRM_VBLANK_RELATIVE;
-   vbl.request.sequence = 0;
-   if ( dPriv && dPriv->vblFlags & VBLANK_FLAG_SECONDARY )
-      vbl.request.type |= DRM_VBLANK_SECONDARY;
-
-   ret = drmWaitVBlank( priv->fd, &vbl );
-
-   if (dPriv) {
-      *count = vblank_to_msc(dPriv, vbl.reply.sequence);
-   } else {
-      /* Old driver (no knowledge of drawable MSC callback) */
-      *count = vbl.reply.sequence;
-   }
-
-   return ret;
-}
-
-/****************************************************************************/
-/**
- * Wait for a specified refresh count.  This implements most of the
- * functionality of \c glXWaitForMscOML from the GLX_OML_sync_control spec.
- * Waits for the \c target_msc refresh.  If that has already passed, it
- * waits until \f$(MSC \bmod divisor)\f$ is equal to \c remainder.  If 
- * \c target_msc is 0, use the behavior of glXWaitVideoSyncSGI(), which
- * omits the initial check against a target MSC value.
- * 
- * This function is actually something of a hack.  The problem is that, at
- * the time of this writing, none of the existing DRM modules support an
- * ioctl that returns a 64-bit count (at least not on 32-bit platforms).
- * However, this function exists to support a GLX function that requires
- * the use of 64-bit counts.  As such, there is a little bit of ugly
- * hackery at the end of this function to make the 32-bit count act like
- * a 64-bit count.  There are still some cases where this will break, but
- * I believe it catches the most common cases.
- *
- * The real solution is to provide an ioctl that uses a 64-bit count.
- *
- * \param dpy         Pointer to the \c Display.
- * \param priv        Pointer to the DRI drawable private.
- * \param target_msc  Desired refresh count to wait for.  A value of 0
- *                    means to use the glXWaitVideoSyncSGI() behavior.
- * \param divisor     MSC divisor if \c target_msc is already reached.
- * \param remainder   Desired MSC remainder if \c target_msc is already
- *                    reached.
- * \param msc         Buffer to hold MSC when done waiting.
- *
- * \return            Zero on success or \c GLX_BAD_CONTEXT on failure.
- */
-
-int driWaitForMSC32( __DRIdrawable *priv,
-		     int64_t target_msc, int64_t divisor, int64_t remainder,
-		     int64_t * msc )
-{
-   drmVBlank vbl;
-
-
-   if ( divisor != 0 ) {
-      int64_t next = target_msc;
-      int64_t r;
-      int dont_wait = (target_msc == 0);
-
-      do {
-         /* dont_wait means we're using the glXWaitVideoSyncSGI() behavior.
-          * The first time around, just get the current count and proceed 
-          * to the test for (MSC % divisor) == remainder.
-          */
-         vbl.request.type = dont_wait ? DRM_VBLANK_RELATIVE :
-                                        DRM_VBLANK_ABSOLUTE;
-         vbl.request.sequence = next ? msc_to_vblank(priv, next) : 0;
-	 if ( priv->vblFlags & VBLANK_FLAG_SECONDARY )
-	    vbl.request.type |= DRM_VBLANK_SECONDARY;
-
-	 if ( drmWaitVBlank( priv->driScreenPriv->fd, &vbl ) != 0 ) {
-	    /* FIXME: This doesn't seem like the right thing to return here.
-	     */
-	    return GLX_BAD_CONTEXT;
-	 }
-
-	 *msc = vblank_to_msc(priv, vbl.reply.sequence);
-
-         if (!dont_wait && *msc == next)
-            break;
-         dont_wait = 0;
-
-         /* Assuming the wait-done test fails, the next refresh to wait for
-          * will be one that satisfies (MSC % divisor) == remainder.  The
-          * value (MSC - (MSC % divisor) + remainder) is the refresh value 
-          * closest to the current value that would satisfy the equation.  
-          * If this refresh has already happened, we add divisor to obtain 
-          * the next refresh after the current one that will satisfy it.
-          */
-         r = ((uint64_t)*msc % divisor);
-         next = (*msc - r + remainder);
-         if (next <= *msc)
-	    next += divisor;
-
-      } while (r != remainder);
-   }
-   else {
-      /* If the \c divisor is zero, just wait until the MSC is greater
-       * than or equal to \c target_msc.
-       */
-
-      vbl.request.type = DRM_VBLANK_ABSOLUTE;
-      vbl.request.sequence = target_msc ? msc_to_vblank(priv, target_msc) : 0;
-
-      if ( priv->vblFlags & VBLANK_FLAG_SECONDARY )
-	 vbl.request.type |= DRM_VBLANK_SECONDARY;
-
-      if ( drmWaitVBlank( priv->driScreenPriv->fd, &vbl ) != 0 ) {
-	 /* FIXME: This doesn't seem like the right thing to return here.
-	  */
-	 return GLX_BAD_CONTEXT;
-      }
-   }
-
-   *msc = vblank_to_msc(priv, vbl.reply.sequence);
-
-   if ( *msc < target_msc ) {
-      *msc += 0x0000000100000000LL;
-   }
-
-   return 0;
-}
-
-
-/****************************************************************************/
-/**
- * Gets a set of default vertical-blank-wait flags based on the internal GLX
- * API version and several configuration options.
- */
-
-GLuint driGetDefaultVBlankFlags( const driOptionCache *optionCache )
-{
-   GLuint  flags = VBLANK_FLAG_INTERVAL;
-   int vblank_mode;
-
-
-   if ( driCheckOption( optionCache, "vblank_mode", DRI_ENUM ) )
-      vblank_mode = driQueryOptioni( optionCache, "vblank_mode" );
-   else
-      vblank_mode = DRI_CONF_VBLANK_DEF_INTERVAL_1;
-
-   switch (vblank_mode) {
-   case DRI_CONF_VBLANK_NEVER:
-      flags = 0;
-      break;
-   case DRI_CONF_VBLANK_DEF_INTERVAL_0:
-      break;
-   case DRI_CONF_VBLANK_DEF_INTERVAL_1:
-      flags |= VBLANK_FLAG_THROTTLE;
-      break;
-   case DRI_CONF_VBLANK_ALWAYS_SYNC:
-      flags |= VBLANK_FLAG_SYNC;
-      break;
-   }
-
-   return flags;
-}
-
-
-/****************************************************************************/
-/**
- * Wrapper to call \c drmWaitVBlank.  The main purpose of this function is to
- * wrap the error message logging.  The error message should only be logged
- * the first time the \c drmWaitVBlank fails.  If \c drmWaitVBlank is
- * successful, \c vbl_seq will be set the sequence value in the reply.
- *
- * \param vbl      Pointer to drmVBlank packet desribing how to wait.
- * \param vbl_seq  Location to store the current refresh counter.
- * \param fd       File descriptor use to call into the DRM.
- * \return         Zero on success or -1 on failure.
- */
-
-static int do_wait( drmVBlank * vbl, GLuint * vbl_seq, int fd )
-{
-   int   ret;
-
-
-   ret = drmWaitVBlank( fd, vbl );
-   if ( ret != 0 ) {
-      static GLboolean first_time = GL_TRUE;
-
-      if ( first_time ) {
-	 fprintf(stderr, 
-		 "%s: drmWaitVBlank returned %d, IRQs don't seem to be"
-		 " working correctly.\nTry adjusting the vblank_mode"
-		 " configuration parameter.\n", __FUNCTION__, ret);
-	 first_time = GL_FALSE;
-      }
-
-      return -1;
-   }
-
-   *vbl_seq = vbl->reply.sequence;
-   return 0;
-}
-
-
-/****************************************************************************/
-/**
- * Returns the default swap interval of the given drawable.
- */
-
-static unsigned
-driGetDefaultVBlankInterval( const  __DRIdrawable *priv )
-{
-   if ( (priv->vblFlags & (VBLANK_FLAG_THROTTLE | VBLANK_FLAG_SYNC)) != 0 ) {
-      return 1;
-   }
-   else {
-      return 0;
-   }
-}
-
-
-/****************************************************************************/
-/**
- * Sets the default swap interval when the drawable is first bound to a
- * direct rendering context.
- */
-
-void driDrawableInitVBlank( __DRIdrawable *priv )
-{
-   if ( priv->swap_interval == (unsigned)-1 &&
-	!( priv->vblFlags & VBLANK_FLAG_NO_IRQ ) ) {
-      /* Get current vertical blank sequence */
-      drmVBlank vbl;
- 
-      vbl.request.type = DRM_VBLANK_RELATIVE;
-      if ( priv->vblFlags & VBLANK_FLAG_SECONDARY )
- 	 vbl.request.type |= DRM_VBLANK_SECONDARY;
-      vbl.request.sequence = 0;
-      do_wait( &vbl, &priv->vblSeq, priv->driScreenPriv->fd );
-      priv->vblank_base = priv->vblSeq;
-
-      priv->swap_interval = driGetDefaultVBlankInterval( priv );
-   }
-}
-
-
-/****************************************************************************/
-/**
- * Returns the current swap interval of the given drawable.
- */
-
-unsigned
-driGetVBlankInterval( const  __DRIdrawable *priv )
-{
-   if ( (priv->vblFlags & VBLANK_FLAG_INTERVAL) != 0 ) {
-      /* this must have been initialized when the drawable was first bound
-       * to a direct rendering context. */
-      assert ( priv->swap_interval != (unsigned)-1 );
-
-      return priv->swap_interval;
-   }
-   else 
-      return driGetDefaultVBlankInterval( priv );
-}
-
-
-/****************************************************************************/
-/**
- * Returns the current vertical blank sequence number of the given drawable.
- */
-
-void
-driGetCurrentVBlank( __DRIdrawable *priv )
-{
-   drmVBlank vbl;
-
-   vbl.request.type = DRM_VBLANK_RELATIVE;
-   if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) {
-      vbl.request.type |= DRM_VBLANK_SECONDARY;
-   }
-   vbl.request.sequence = 0;
-
-   (void) do_wait( &vbl, &priv->vblSeq, priv->driScreenPriv->fd );
-}
-
-
-/****************************************************************************/
-/**
- * Waits for the vertical blank for use with glXSwapBuffers.
- * 
- * \param missed_deadline  Set to \c GL_TRUE if the MSC after waiting is later
- *                 than the "target" based on \c priv->vblFlags.  The idea is
- *                 that if \c missed_deadline is set, then the application is
- *                 not achieving its desired framerate.
- * \return         Zero on success, -1 on error.
- */
-
-int
-driWaitForVBlank( __DRIdrawable *priv, GLboolean * missed_deadline )
-{
-   drmVBlank vbl;
-   unsigned   original_seq;
-   unsigned   deadline;
-   unsigned   interval;
-   unsigned   diff;
-
-   *missed_deadline = GL_FALSE;
-   if ( (priv->vblFlags & (VBLANK_FLAG_INTERVAL |
-			   VBLANK_FLAG_THROTTLE |
-			   VBLANK_FLAG_SYNC)) == 0 ||
-	(priv->vblFlags & VBLANK_FLAG_NO_IRQ) != 0 ) {
-      return 0;
-   }
-
-
-   /* VBLANK_FLAG_SYNC means to wait for at least one vertical blank.  If
-    * that flag is not set, do a fake wait for zero vertical blanking
-    * periods so that we can get the current MSC.
-    *
-    * VBLANK_FLAG_INTERVAL and VBLANK_FLAG_THROTTLE mean to wait for at
-    * least one vertical blank since the last wait.  Since do_wait modifies
-    * priv->vblSeq, we have to save the original value of priv->vblSeq for the
-    * VBLANK_FLAG_INTERVAL / VBLANK_FLAG_THROTTLE calculation later.
-    */
-
-   original_seq = priv->vblSeq;
-   interval = driGetVBlankInterval(priv);
-   deadline = original_seq + interval;
-
-   vbl.request.type = DRM_VBLANK_RELATIVE;
-   if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) {
-      vbl.request.type |= DRM_VBLANK_SECONDARY;
-   }
-   vbl.request.sequence = ((priv->vblFlags & VBLANK_FLAG_SYNC) != 0) ? 1 : 0;
-
-   if ( do_wait( & vbl, &priv->vblSeq, priv->driScreenPriv->fd ) != 0 ) {
-      return -1;
-   }
-
-   diff = priv->vblSeq - deadline;
-
-   /* No need to wait again if we've already reached the target */
-   if (diff <= (1 << 23)) {
-      *missed_deadline = (priv->vblFlags & VBLANK_FLAG_SYNC) ? (diff > 0) :
-			 GL_TRUE;
-      return 0;
-   }
-
-   /* Wait until the target vertical blank. */
-   vbl.request.type = DRM_VBLANK_ABSOLUTE;
-   if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) {
-      vbl.request.type |= DRM_VBLANK_SECONDARY;
-   }
-   vbl.request.sequence = deadline;
-
-   if ( do_wait( & vbl, &priv->vblSeq, priv->driScreenPriv->fd ) != 0 ) {
-      return -1;
-   }
-
-   diff = priv->vblSeq - deadline;
-   *missed_deadline = diff > 0 && diff <= (1 << 23);
-
-   return 0;
-}
+/* -*- mode: c; c-basic-offset: 3 -*- */
+/*
+ * (c) Copyright IBM Corporation 2002
+ * 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
+ * on 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
+ * VA LINUX SYSTEM, IBM AND/OR THEIR 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.
+ *
+ * Authors:
+ *    Ian Romanick <idr@us.ibm.com>
+ */
+
+#include "main/glheader.h"
+#include "xf86drm.h"
+#include "main/mtypes.h"
+#include "main/macros.h"
+#include "main/dd.h"
+#include "vblank.h"
+#include "xmlpool.h"
+
+static unsigned int msc_to_vblank(__DRIdrawable * dPriv, int64_t msc)
+{
+   return (unsigned int)(msc - dPriv->msc_base + dPriv->vblank_base);
+}
+
+static int64_t vblank_to_msc(__DRIdrawable * dPriv, unsigned int vblank)
+{
+   return (int64_t)(vblank - dPriv->vblank_base + dPriv->msc_base);
+}
+
+
+/****************************************************************************/
+/**
+ * Get the current MSC refresh counter.
+ *
+ * Stores the 64-bit count of vertical refreshes since some (arbitrary)
+ * point in time in \c count.  Unless the value wraps around, which it
+ * may, it will never decrease for a given drawable.
+ *
+ * \warning This function is called from \c glXGetVideoSyncSGI, which expects
+ * a \c count of type \c unsigned (32-bit), and \c glXGetSyncValuesOML, which 
+ * expects a \c count of type \c int64_t (signed 64-bit).  The kernel ioctl 
+ * currently always returns a \c sequence of type \c unsigned.
+ *
+ * \param priv   Pointer to the DRI screen private struct.
+ * \param dPriv  Pointer to the DRI drawable private struct
+ * \param count  Storage to hold MSC counter.
+ * \return       Zero is returned on success.  A negative errno value
+ *               is returned on failure.
+ */
+int driDrawableGetMSC32( __DRIscreen * priv,
+			 __DRIdrawable * dPriv,
+			 int64_t * count)
+{
+   drmVBlank vbl;
+   int ret;
+
+   /* Don't wait for anything.  Just get the current refresh count. */
+
+   vbl.request.type = DRM_VBLANK_RELATIVE;
+   vbl.request.sequence = 0;
+   if ( dPriv && dPriv->vblFlags & VBLANK_FLAG_SECONDARY )
+      vbl.request.type |= DRM_VBLANK_SECONDARY;
+
+   ret = drmWaitVBlank( priv->fd, &vbl );
+
+   if (dPriv) {
+      *count = vblank_to_msc(dPriv, vbl.reply.sequence);
+   } else {
+      /* Old driver (no knowledge of drawable MSC callback) */
+      *count = vbl.reply.sequence;
+   }
+
+   return ret;
+}
+
+/****************************************************************************/
+/**
+ * Wait for a specified refresh count.  This implements most of the
+ * functionality of \c glXWaitForMscOML from the GLX_OML_sync_control spec.
+ * Waits for the \c target_msc refresh.  If that has already passed, it
+ * waits until \f$(MSC \bmod divisor)\f$ is equal to \c remainder.  If 
+ * \c target_msc is 0, use the behavior of glXWaitVideoSyncSGI(), which
+ * omits the initial check against a target MSC value.
+ * 
+ * This function is actually something of a hack.  The problem is that, at
+ * the time of this writing, none of the existing DRM modules support an
+ * ioctl that returns a 64-bit count (at least not on 32-bit platforms).
+ * However, this function exists to support a GLX function that requires
+ * the use of 64-bit counts.  As such, there is a little bit of ugly
+ * hackery at the end of this function to make the 32-bit count act like
+ * a 64-bit count.  There are still some cases where this will break, but
+ * I believe it catches the most common cases.
+ *
+ * The real solution is to provide an ioctl that uses a 64-bit count.
+ *
+ * \param dpy         Pointer to the \c Display.
+ * \param priv        Pointer to the DRI drawable private.
+ * \param target_msc  Desired refresh count to wait for.  A value of 0
+ *                    means to use the glXWaitVideoSyncSGI() behavior.
+ * \param divisor     MSC divisor if \c target_msc is already reached.
+ * \param remainder   Desired MSC remainder if \c target_msc is already
+ *                    reached.
+ * \param msc         Buffer to hold MSC when done waiting.
+ *
+ * \return            Zero on success or \c GLX_BAD_CONTEXT on failure.
+ */
+
+int driWaitForMSC32( __DRIdrawable *priv,
+		     int64_t target_msc, int64_t divisor, int64_t remainder,
+		     int64_t * msc )
+{
+   drmVBlank vbl;
+
+
+   if ( divisor != 0 ) {
+      int64_t next = target_msc;
+      int64_t r;
+      int dont_wait = (target_msc == 0);
+
+      do {
+         /* dont_wait means we're using the glXWaitVideoSyncSGI() behavior.
+          * The first time around, just get the current count and proceed 
+          * to the test for (MSC % divisor) == remainder.
+          */
+         vbl.request.type = dont_wait ? DRM_VBLANK_RELATIVE :
+                                        DRM_VBLANK_ABSOLUTE;
+         vbl.request.sequence = next ? msc_to_vblank(priv, next) : 0;
+	 if ( priv->vblFlags & VBLANK_FLAG_SECONDARY )
+	    vbl.request.type |= DRM_VBLANK_SECONDARY;
+
+	 if ( drmWaitVBlank( priv->driScreenPriv->fd, &vbl ) != 0 ) {
+	    /* FIXME: This doesn't seem like the right thing to return here.
+	     */
+	    return GLX_BAD_CONTEXT;
+	 }
+
+	 *msc = vblank_to_msc(priv, vbl.reply.sequence);
+
+         if (!dont_wait && *msc == next)
+            break;
+         dont_wait = 0;
+
+         /* Assuming the wait-done test fails, the next refresh to wait for
+          * will be one that satisfies (MSC % divisor) == remainder.  The
+          * value (MSC - (MSC % divisor) + remainder) is the refresh value 
+          * closest to the current value that would satisfy the equation.  
+          * If this refresh has already happened, we add divisor to obtain 
+          * the next refresh after the current one that will satisfy it.
+          */
+         r = ((uint64_t)*msc % divisor);
+         next = (*msc - r + remainder);
+         if (next <= *msc)
+	    next += divisor;
+
+      } while (r != remainder);
+   }
+   else {
+      /* If the \c divisor is zero, just wait until the MSC is greater
+       * than or equal to \c target_msc.
+       */
+
+      vbl.request.type = DRM_VBLANK_ABSOLUTE;
+      vbl.request.sequence = target_msc ? msc_to_vblank(priv, target_msc) : 0;
+
+      if ( priv->vblFlags & VBLANK_FLAG_SECONDARY )
+	 vbl.request.type |= DRM_VBLANK_SECONDARY;
+
+      if ( drmWaitVBlank( priv->driScreenPriv->fd, &vbl ) != 0 ) {
+	 /* FIXME: This doesn't seem like the right thing to return here.
+	  */
+	 return GLX_BAD_CONTEXT;
+      }
+   }
+
+   *msc = vblank_to_msc(priv, vbl.reply.sequence);
+
+   if ( *msc < target_msc ) {
+      *msc += 0x0000000100000000LL;
+   }
+
+   return 0;
+}
+
+
+/****************************************************************************/
+/**
+ * Gets a set of default vertical-blank-wait flags based on the internal GLX
+ * API version and several configuration options.
+ */
+
+GLuint driGetDefaultVBlankFlags( const driOptionCache *optionCache )
+{
+   GLuint  flags = VBLANK_FLAG_INTERVAL;
+   int vblank_mode;
+
+
+   if ( driCheckOption( optionCache, "vblank_mode", DRI_ENUM ) )
+      vblank_mode = driQueryOptioni( optionCache, "vblank_mode" );
+   else
+      vblank_mode = DRI_CONF_VBLANK_DEF_INTERVAL_1;
+
+   switch (vblank_mode) {
+   case DRI_CONF_VBLANK_NEVER:
+      flags = 0;
+      break;
+   case DRI_CONF_VBLANK_DEF_INTERVAL_0:
+      break;
+   case DRI_CONF_VBLANK_DEF_INTERVAL_1:
+      flags |= VBLANK_FLAG_THROTTLE;
+      break;
+   case DRI_CONF_VBLANK_ALWAYS_SYNC:
+      flags |= VBLANK_FLAG_SYNC;
+      break;
+   }
+
+   return flags;
+}
+
+
+/****************************************************************************/
+/**
+ * Wrapper to call \c drmWaitVBlank.  The main purpose of this function is to
+ * wrap the error message logging.  The error message should only be logged
+ * the first time the \c drmWaitVBlank fails.  If \c drmWaitVBlank is
+ * successful, \c vbl_seq will be set the sequence value in the reply.
+ *
+ * \param vbl      Pointer to drmVBlank packet describing how to wait.
+ * \param vbl_seq  Location to store the current refresh counter.
+ * \param fd       File descriptor use to call into the DRM.
+ * \return         Zero on success or -1 on failure.
+ */
+
+static int do_wait( drmVBlank * vbl, GLuint * vbl_seq, int fd )
+{
+   int   ret;
+
+
+   ret = drmWaitVBlank( fd, vbl );
+   if ( ret != 0 ) {
+      static GLboolean first_time = GL_TRUE;
+
+      if ( first_time ) {
+	 fprintf(stderr, 
+		 "%s: drmWaitVBlank returned %d, IRQs don't seem to be"
+		 " working correctly.\nTry adjusting the vblank_mode"
+		 " configuration parameter.\n", __FUNCTION__, ret);
+	 first_time = GL_FALSE;
+      }
+
+      return -1;
+   }
+
+   *vbl_seq = vbl->reply.sequence;
+   return 0;
+}
+
+
+/****************************************************************************/
+/**
+ * Returns the default swap interval of the given drawable.
+ */
+
+static unsigned
+driGetDefaultVBlankInterval( const  __DRIdrawable *priv )
+{
+   if ( (priv->vblFlags & (VBLANK_FLAG_THROTTLE | VBLANK_FLAG_SYNC)) != 0 ) {
+      return 1;
+   }
+   else {
+      return 0;
+   }
+}
+
+
+/****************************************************************************/
+/**
+ * Sets the default swap interval when the drawable is first bound to a
+ * direct rendering context.
+ */
+
+void driDrawableInitVBlank( __DRIdrawable *priv )
+{
+   if ( priv->swap_interval == (unsigned)-1 &&
+	!( priv->vblFlags & VBLANK_FLAG_NO_IRQ ) ) {
+      /* Get current vertical blank sequence */
+      drmVBlank vbl;
+ 
+      vbl.request.type = DRM_VBLANK_RELATIVE;
+      if ( priv->vblFlags & VBLANK_FLAG_SECONDARY )
+ 	 vbl.request.type |= DRM_VBLANK_SECONDARY;
+      vbl.request.sequence = 0;
+      do_wait( &vbl, &priv->vblSeq, priv->driScreenPriv->fd );
+      priv->vblank_base = priv->vblSeq;
+
+      priv->swap_interval = driGetDefaultVBlankInterval( priv );
+   }
+}
+
+
+/****************************************************************************/
+/**
+ * Returns the current swap interval of the given drawable.
+ */
+
+unsigned
+driGetVBlankInterval( const  __DRIdrawable *priv )
+{
+   if ( (priv->vblFlags & VBLANK_FLAG_INTERVAL) != 0 ) {
+      /* this must have been initialized when the drawable was first bound
+       * to a direct rendering context. */
+      assert ( priv->swap_interval != (unsigned)-1 );
+
+      return priv->swap_interval;
+   }
+   else 
+      return driGetDefaultVBlankInterval( priv );
+}
+
+
+/****************************************************************************/
+/**
+ * Returns the current vertical blank sequence number of the given drawable.
+ */
+
+void
+driGetCurrentVBlank( __DRIdrawable *priv )
+{
+   drmVBlank vbl;
+
+   vbl.request.type = DRM_VBLANK_RELATIVE;
+   if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) {
+      vbl.request.type |= DRM_VBLANK_SECONDARY;
+   }
+   vbl.request.sequence = 0;
+
+   (void) do_wait( &vbl, &priv->vblSeq, priv->driScreenPriv->fd );
+}
+
+
+/****************************************************************************/
+/**
+ * Waits for the vertical blank for use with glXSwapBuffers.
+ * 
+ * \param missed_deadline  Set to \c GL_TRUE if the MSC after waiting is later
+ *                 than the "target" based on \c priv->vblFlags.  The idea is
+ *                 that if \c missed_deadline is set, then the application is
+ *                 not achieving its desired framerate.
+ * \return         Zero on success, -1 on error.
+ */
+
+int
+driWaitForVBlank( __DRIdrawable *priv, GLboolean * missed_deadline )
+{
+   drmVBlank vbl;
+   unsigned   original_seq;
+   unsigned   deadline;
+   unsigned   interval;
+   unsigned   diff;
+
+   *missed_deadline = GL_FALSE;
+   if ( (priv->vblFlags & (VBLANK_FLAG_INTERVAL |
+			   VBLANK_FLAG_THROTTLE |
+			   VBLANK_FLAG_SYNC)) == 0 ||
+	(priv->vblFlags & VBLANK_FLAG_NO_IRQ) != 0 ) {
+      return 0;
+   }
+
+
+   /* VBLANK_FLAG_SYNC means to wait for at least one vertical blank.  If
+    * that flag is not set, do a fake wait for zero vertical blanking
+    * periods so that we can get the current MSC.
+    *
+    * VBLANK_FLAG_INTERVAL and VBLANK_FLAG_THROTTLE mean to wait for at
+    * least one vertical blank since the last wait.  Since do_wait modifies
+    * priv->vblSeq, we have to save the original value of priv->vblSeq for the
+    * VBLANK_FLAG_INTERVAL / VBLANK_FLAG_THROTTLE calculation later.
+    */
+
+   original_seq = priv->vblSeq;
+   interval = driGetVBlankInterval(priv);
+   deadline = original_seq + interval;
+
+   vbl.request.type = DRM_VBLANK_RELATIVE;
+   if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) {
+      vbl.request.type |= DRM_VBLANK_SECONDARY;
+   }
+   vbl.request.sequence = ((priv->vblFlags & VBLANK_FLAG_SYNC) != 0) ? 1 : 0;
+
+   if ( do_wait( & vbl, &priv->vblSeq, priv->driScreenPriv->fd ) != 0 ) {
+      return -1;
+   }
+
+   diff = priv->vblSeq - deadline;
+
+   /* No need to wait again if we've already reached the target */
+   if (diff <= (1 << 23)) {
+      *missed_deadline = (priv->vblFlags & VBLANK_FLAG_SYNC) ? (diff > 0) :
+			 GL_TRUE;
+      return 0;
+   }
+
+   /* Wait until the target vertical blank. */
+   vbl.request.type = DRM_VBLANK_ABSOLUTE;
+   if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) {
+      vbl.request.type |= DRM_VBLANK_SECONDARY;
+   }
+   vbl.request.sequence = deadline;
+
+   if ( do_wait( & vbl, &priv->vblSeq, priv->driScreenPriv->fd ) != 0 ) {
+      return -1;
+   }
+
+   diff = priv->vblSeq - deadline;
+   *missed_deadline = diff > 0 && diff <= (1 << 23);
+
+   return 0;
+}