DRI2: add OML_sync_control support

Add OML_sync_control support, along with a simple program for testing
it.  This means adding support for the DRI2GetMSC, DRI2WaitMSC and
DRI2WaitSBC requests.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

12 files changed, 627 insertions, 185 deletions

diff --git a/progs/xdemos/.gitignore b/progs/xdemos/.gitignore
index 1b9b3a87c0..5ae0f5a062 100644
--- a/progs/xdemos/.gitignore
+++ b/progs/xdemos/.gitignore
@@ -26,3 +26,4 @@ xdemo
 xfont
 xrotfontdemo
 yuvrect_client
+msctest
diff --git a/progs/xdemos/Makefile b/progs/xdemos/Makefile
index 77f667978c..f866a32865 100644
--- a/progs/xdemos/Makefile
+++ b/progs/xdemos/Makefile
@@ -29,6 +29,7 @@ PROGS = \
 	glxsnoop \
 	glxswapcontrol \
 	manywin \
+	msctest \
 	multictx \
 	offset \
 	overlay \
diff --git a/progs/xdemos/msctest.c b/progs/xdemos/msctest.c
new file mode 100644
index 0000000000..001ecf04d6
--- /dev/null
+++ b/progs/xdemos/msctest.c
@@ -0,0 +1,202 @@
+/*
+ * Copyright © 2009 Intel Corporation
+ *
+ * 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, sublicense,
+ * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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:
+ *    Jesse Barnes <jesse.barnes@intel.com>
+ *
+ */
+
+/** @file msctest.c
+ * Simple test for MSC functionality.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/glx.h>
+#include <GL/glxext.h>
+#include <X11/X.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+
+void (*get_sync_values)(Display *dpy, Window winGL, int64_t *ust, int64_t *msc, int64_t *sbc);
+void (*wait_sync)(Display *dpy, Window winGL, int64_t target_msc, int64_t divisor, int64_t remainder, int64_t *ust, int64_t *msc, int64_t *sbc);
+
+static int GLXExtensionSupported(Display *dpy, const char *extension)
+{
+	const char *extensionsString, *client_extensions, *pos;
+
+	extensionsString = glXQueryExtensionsString(dpy, DefaultScreen(dpy));
+	client_extensions = glXGetClientString(dpy, GLX_EXTENSIONS);
+
+	pos = strstr(extensionsString, extension);
+
+	if (pos != NULL && (pos == extensionsString || pos[-1] == ' ') &&
+	    (pos[strlen(extension)] == ' ' || pos[strlen(extension)] == '\0'))
+		return 1;
+
+	pos = strstr(client_extensions, extension);
+
+	if (pos != NULL && (pos == extensionsString || pos[-1] == ' ') &&
+	    (pos[strlen(extension)] == ' ' || pos[strlen(extension)] == '\0'))
+		return 1;
+
+	return 0;
+}
+
+extern char *optarg;
+extern int optind, opterr, optopt;
+static char optstr[] = "v";
+
+static void usage(char *name)
+{
+	printf("usage: %s\n", name);
+	exit(-1);
+}
+
+int main(int argc, char *argv[])
+{
+	Display *disp;
+	XVisualInfo *pvi;
+	XSetWindowAttributes swa;
+	int attrib[14];
+	Window winGL;
+	GLXContext context;
+	int dummy;
+	Atom wmDelete;
+	int verbose = 0, width = 200, height = 200;
+	int c, i = 1;
+	int64_t ust, msc, sbc;
+
+	opterr = 0;
+	while ((c = getopt(argc, argv, optstr)) != -1) {
+		switch (c) {
+		case 'v':
+			verbose = 1;
+			break;
+		default:
+			usage(argv[0]);
+			break;
+		}
+	}
+
+	disp = XOpenDisplay(NULL);
+	if (!disp) {
+		fprintf(stderr, "failed to open display\n");
+		return -1;
+	}
+
+	if (!glXQueryExtension(disp, &dummy, &dummy)) {
+		fprintf(stderr, "glXQueryExtension failed\n");
+		return -1;
+	}
+
+	if (!GLXExtensionSupported(disp, "GLX_OML_sync_control")) {
+		fprintf(stderr, "GLX_OML_sync_control not supported, exiting\n");
+		return -1;
+	}
+
+	attrib[0] = GLX_RGBA;
+	attrib[1] = 1;
+	attrib[2] = GLX_RED_SIZE;
+	attrib[3] = 1;
+	attrib[4] = GLX_GREEN_SIZE;
+	attrib[5] = 1;
+	attrib[6] = GLX_BLUE_SIZE;
+	attrib[7] = 1;
+	attrib[8] = GLX_DOUBLEBUFFER;
+	attrib[9] = 1;
+	attrib[10] = None;
+
+	pvi = glXChooseVisual(disp, DefaultScreen(disp), attrib);
+	if (!pvi) {
+		fprintf(stderr, "failed to choose visual, exiting\n");
+		return -1;
+	}
+
+	context = glXCreateContext(disp, pvi, None, GL_TRUE);
+	if (!context) {
+		fprintf(stderr, "failed to create glx context\n");
+		return -1;
+	}
+
+	pvi->screen = DefaultScreen(disp);
+
+	swa.colormap = XCreateColormap(disp, RootWindow(disp, pvi->screen),
+				       pvi->visual, AllocNone);
+	swa.border_pixel = 0;
+	swa.event_mask = ExposureMask | KeyPressMask | ButtonPressMask |
+		StructureNotifyMask;
+	winGL = XCreateWindow(disp, RootWindow(disp, pvi->screen),
+			      0, 0,
+			      width, height,
+			      0, pvi->depth, InputOutput, pvi->visual,
+			      CWBorderPixel | CWColormap | CWEventMask, &swa);
+	if (!winGL) {
+		fprintf(stderr, "window creation failed\n");
+		return -1;
+	}
+        wmDelete = XInternAtom(disp, "WM_DELETE_WINDOW", True);
+        XSetWMProtocols(disp, winGL, &wmDelete, 1);
+
+	XSetStandardProperties(disp, winGL, "msc test", "msc text",
+			       None, NULL, 0, NULL);
+
+	XMapRaised(disp, winGL);
+
+	glXMakeCurrent(disp, winGL, context);
+
+	get_sync_values = glXGetProcAddress((unsigned char *)"glXGetSyncValuesOML");
+	wait_sync = glXGetProcAddress((unsigned char *)"glXWaitForMscOML");
+
+	if (!get_sync_values || !wait_sync) {
+		fprintf(stderr, "failed to get sync values function\n");
+		return -1;
+	}
+
+	while (i++) {
+		get_sync_values(disp, winGL, &ust, &msc, &sbc);
+		fprintf(stderr, "ust: %llu, msc: %llu, sbc: %llu\n", ust, msc,
+			sbc);
+
+		/* Alternate colors to make tearing obvious */
+		if (i & 1)
+			glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
+		else
+			glClearColor(1.0f, 0.0f, 0.0f, 0.0f);
+		glClear(GL_COLOR_BUFFER_BIT);
+		glXSwapBuffers(disp, winGL);
+		wait_sync(disp, winGL, 0, 60, 0, &ust, &msc, &sbc);
+		fprintf(stderr,
+			"wait returned ust: %llu, msc: %llu, sbc: %llu\n",
+			ust, msc, sbc);
+		sleep(1);
+	}
+
+	XDestroyWindow(disp, winGL);
+	glXDestroyContext(disp, context);
+	XCloseDisplay(disp);
+
+	return 0;
+}
diff --git a/src/glx/x11/dri2.c b/src/glx/x11/dri2.c
index a0f8901d42..922edbdcf5 100644
--- a/src/glx/x11/dri2.c
+++ b/src/glx/x11/dri2.c
@@ -34,6 +34,7 @@
 #ifdef GLX_DIRECT_RENDERING
 
 #define NEED_REPLIES
+#include <stdio.h>
 #include <X11/Xlibint.h>
 #include <X11/extensions/Xext.h>
 #include <X11/extensions/extutil.h>
@@ -380,10 +381,30 @@ DRI2CopyRegion(Display * dpy, XID drawable, XserverRegion region,
    SyncHandle();
 }
 
-void DRI2SwapBuffers(Display *dpy, XID drawable)
+static void
+load_swap_req(xDRI2SwapBuffersReq *req, CARD64 target, CARD64 divisor,
+	     CARD64 remainder)
+{
+    req->target_msc_hi = target >> 32;
+    req->target_msc_lo = target & 0xffffffff;
+    req->divisor_hi = divisor >> 32;
+    req->divisor_lo = divisor & 0xffffffff;
+    req->remainder_hi = remainder >> 32;
+    req->remainder_lo = remainder & 0xffffffff;
+}
+
+static CARD64
+vals_to_card64(CARD32 lo, CARD32 hi)
+{
+    return (CARD64)hi << 32 | lo;
+}
+
+void DRI2SwapBuffers(Display *dpy, XID drawable, CARD64 target_msc,
+		     CARD64 divisor, CARD64 remainder, CARD64 *count)
 {
     XExtDisplayInfo *info = DRI2FindDisplay(dpy);
     xDRI2SwapBuffersReq *req;
+    xDRI2SwapBuffersReply rep;
 
     XextSimpleCheckExtension (dpy, info, dri2ExtensionName);
 
@@ -392,8 +413,128 @@ void DRI2SwapBuffers(Display *dpy, XID drawable)
     req->reqType = info->codes->major_opcode;
     req->dri2ReqType = X_DRI2SwapBuffers;
     req->drawable = drawable;
+    load_swap_req(req, target_msc, divisor, remainder);
+
+    _XReply(dpy, (xReply *)&rep, 0, xFalse);
+
+    *count = vals_to_card64(rep.swap_lo, rep.swap_hi);
+
+    UnlockDisplay(dpy);
+    SyncHandle();
+}
+
+Bool DRI2GetMSC(Display *dpy, XID drawable, CARD64 *ust, CARD64 *msc,
+		CARD64 *sbc)
+{
+    XExtDisplayInfo *info = DRI2FindDisplay(dpy);
+    xDRI2GetMSCReq *req;
+    xDRI2MSCReply rep;
+
+    XextCheckExtension (dpy, info, dri2ExtensionName, False);
+
+    LockDisplay(dpy);
+    GetReq(DRI2GetMSC, req);
+    req->reqType = info->codes->major_opcode;
+    req->dri2ReqType = X_DRI2GetMSC;
+    req->drawable = drawable;
+
+    if (!_XReply(dpy, (xReply *)&rep, 0, xFalse)) {
+	UnlockDisplay(dpy);
+	SyncHandle();
+	return False;
+    }
+
+    *ust = vals_to_card64(rep.ust_lo, rep.ust_hi);
+    *msc = vals_to_card64(rep.msc_lo, rep.msc_hi);
+    *sbc = vals_to_card64(rep.sbc_lo, rep.sbc_hi);
+
+    UnlockDisplay(dpy);
+    SyncHandle();
+
+    return True;
+}
+
+static void
+load_msc_req(xDRI2WaitMSCReq *req, CARD64 target, CARD64 divisor,
+	     CARD64 remainder)
+{
+    req->target_msc_hi = target >> 32;
+    req->target_msc_lo = target & 0xffffffff;
+    req->divisor_hi = divisor >> 32;
+    req->divisor_lo = divisor & 0xffffffff;
+    req->remainder_hi = remainder >> 32;
+    req->remainder_lo = remainder & 0xffffffff;
+}
+
+Bool DRI2WaitMSC(Display *dpy, XID drawable, CARD64 target_msc, CARD64 divisor,
+		 CARD64 remainder, CARD64 *ust, CARD64 *msc, CARD64 *sbc)
+{
+    XExtDisplayInfo *info = DRI2FindDisplay(dpy);
+    xDRI2WaitMSCReq *req;
+    xDRI2MSCReply rep;
+
+    XextCheckExtension (dpy, info, dri2ExtensionName, False);
+
+    LockDisplay(dpy);
+    GetReq(DRI2WaitMSC, req);
+    req->reqType = info->codes->major_opcode;
+    req->dri2ReqType = X_DRI2WaitMSC;
+    req->drawable = drawable;
+    load_msc_req(req, target_msc, divisor, remainder);
+
+    if (!_XReply(dpy, (xReply *)&rep, 0, xFalse)) {
+	UnlockDisplay(dpy);
+	SyncHandle();
+	return False;
+    }
+
+    *ust = ((CARD64)rep.ust_hi << 32) | (CARD64)rep.ust_lo;
+    *msc = ((CARD64)rep.msc_hi << 32) | (CARD64)rep.msc_lo;
+    *sbc = ((CARD64)rep.sbc_hi << 32) | (CARD64)rep.sbc_lo;
+
+    UnlockDisplay(dpy);
+    SyncHandle();
+
+    return True;
+}
+
+static void
+load_sbc_req(xDRI2WaitSBCReq *req, CARD64 target)
+{
+    req->target_sbc_hi = target >> 32;
+    req->target_sbc_lo = target & 0xffffffff;
+}
+
+Bool DRI2WaitSBC(Display *dpy, XID drawable, CARD64 target_sbc, CARD64 *ust,
+		 CARD64 *msc, CARD64 *sbc)
+{
+    XExtDisplayInfo *info = DRI2FindDisplay(dpy);
+    xDRI2WaitSBCReq *req;
+    xDRI2MSCReply rep;
+
+    XextCheckExtension (dpy, info, dri2ExtensionName, False);
+
+    LockDisplay(dpy);
+    GetReq(DRI2WaitSBC, req);
+    req->reqType = info->codes->major_opcode;
+    req->dri2ReqType = X_DRI2WaitSBC;
+    req->drawable = drawable;
+    load_sbc_req(req, target_sbc);
+
+    if (!_XReply(dpy, (xReply *)&rep, 0, xFalse)) {
+	UnlockDisplay(dpy);
+	SyncHandle();
+	return False;
+    }
+
+    *ust = ((CARD64)rep.ust_hi << 32) | rep.ust_lo;
+    *msc = ((CARD64)rep.msc_hi << 32) | rep.msc_lo;
+    *sbc = ((CARD64)rep.sbc_hi << 32) | rep.sbc_lo;
+
     UnlockDisplay(dpy);
     SyncHandle();
+
+    return True;
 }
 
 #endif /* GLX_DIRECT_RENDERING */
diff --git a/src/glx/x11/dri2.h b/src/glx/x11/dri2.h
index ba6eff5e4f..ae6030842c 100644
--- a/src/glx/x11/dri2.h
+++ b/src/glx/x11/dri2.h
@@ -86,6 +86,18 @@ DRI2CopyRegion(Display * dpy, XID drawable,
                CARD32 dest, CARD32 src);
 
 extern void
-DRI2SwapBuffers(Display *dpy, XID drawable);
+DRI2SwapBuffers(Display *dpy, XID drawable, CARD64 target_msc, CARD64 divisor,
+		CARD64 remainder, CARD64 *count);
+
+extern Bool
+DRI2GetMSC(Display *dpy, XID drawable, CARD64 *ust, CARD64 *msc, CARD64 *sbc);
+
+extern Bool
+DRI2WaitMSC(Display *dpy, XID drawable, CARD64 target_msc, CARD64 divisor,
+	    CARD64 remainder, CARD64 *ust, CARD64 *msc, CARD64 *sbc);
+
+extern Bool
+DRI2WaitSBC(Display *dpy, XID drawable, CARD64 target_sbc, CARD64 *ust,
+	    CARD64 *msc, CARD64 *sbc);
 
 #endif
diff --git a/src/glx/x11/dri2_glx.c b/src/glx/x11/dri2_glx.c
index 114cad2ae7..86bfe46a85 100644
--- a/src/glx/x11/dri2_glx.c
+++ b/src/glx/x11/dri2_glx.c
@@ -199,9 +199,31 @@ dri2CreateDrawable(__GLXscreenConfigs * psc,
    return &pdraw->base;
 }
 
+static int
+dri2DrawableGetMSC(__GLXscreenConfigs *psc, __GLXDRIdrawable *pdraw,
+		   int64_t *ust, int64_t *msc, int64_t *sbc)
+{
+   return DRI2GetMSC(psc->dpy, pdraw->drawable, ust, msc, sbc);
+}
+
+static int
+dri2WaitForMSC(__GLXDRIdrawable *pdraw, int64_t target_msc, int64_t divisor,
+	       int64_t remainder, int64_t *ust, int64_t *msc, int64_t *sbc)
+{
+   return DRI2WaitMSC(pdraw->psc->dpy, pdraw->drawable, target_msc, divisor,
+		      remainder, ust, msc, sbc);
+}
+
+static int
+dri2WaitForSBC(__GLXDRIdrawable *pdraw, int64_t target_sbc, int64_t *ust,
+	       int64_t *msc, int64_t *sbc)
+{
+   return DRI2WaitSBC(pdraw->psc->dpy, pdraw->drawable, target_sbc, ust, msc,
+		      sbc);
+}
+
 static void
-dri2CopySubBuffer(__GLXDRIdrawable * pdraw,
-                  int x, int y, int width, int height)
+dri2CopySubBuffer(__GLXDRIdrawable *pdraw, int x, int y, int width, int height)
 {
    __GLXDRIdrawablePrivate *priv = (__GLXDRIdrawablePrivate *) pdraw;
    XRectangle xrect;
@@ -234,14 +256,6 @@ dri2CopySubBuffer(__GLXDRIdrawable * pdraw,
 }
 
 static void
-dri2SwapBuffers(__GLXDRIdrawable * pdraw)
-{
-   __GLXDRIdrawablePrivate *priv = (__GLXDRIdrawablePrivate *) pdraw;
-
-   dri2CopySubBuffer(pdraw, 0, 0, priv->width, priv->height);
-}
-
-static void
 dri2WaitX(__GLXDRIdrawable *pdraw)
 {
    __GLXDRIdrawablePrivate *priv = (__GLXDRIdrawablePrivate *) pdraw;
@@ -344,13 +358,15 @@ process_buffers(__GLXDRIdrawablePrivate * pdraw, DRI2Buffer * buffers,
 
 }
 
-static void dri2SwapBuffers(__GLXDRIdrawable *pdraw)
+static int64_t
+dri2SwapBuffers(__GLXDRIdrawable *pdraw, int64_t target_msc, int64_t divisor,
+		int64_t remainder)
 {
     __GLXDRIdrawablePrivate *priv = (__GLXDRIdrawablePrivate *) pdraw;
     __GLXdisplayPrivate *dpyPriv = __glXInitialize(priv->base.psc->dpy);
     __GLXDRIdisplayPrivate *pdp =
 	(__GLXDRIdisplayPrivate *)dpyPriv->dri2Display;
-    __GLXscreenConfigs *psc = pdraw->psc;
+    int64_t ret;
 
 #ifdef __DRI2_FLUSH
     if (pdraw->psc->f)
@@ -358,15 +374,20 @@ static void dri2SwapBuffers(__GLXDRIdrawable *pdraw)
 #endif
 
     /* Old servers can't handle swapbuffers */
-    if (!pdp->swapAvailable)
-	return dri2CopySubBuffer(pdraw, 0, 0, priv->width, priv->height);
+    if (!pdp->swapAvailable) {
+       dri2CopySubBuffer(pdraw, 0, 0, priv->width, priv->height);
+       return 0;
+    }
 
-    DRI2SwapBuffers(pdraw->psc->dpy, pdraw->drawable);
+    DRI2SwapBuffers(pdraw->psc->dpy, pdraw->drawable, target_msc, divisor,
+		    remainder, &ret);
 
 #if __DRI2_FLUSH_VERSION >= 2
     if (pdraw->psc->f)
        (*pdraw->psc->f->flushInvalidate)(pdraw->driDrawable);
 #endif
+
+    return ret;
 }
 
 static __DRIbuffer *
@@ -464,7 +485,7 @@ dri2CreateScreen(__GLXscreenConfigs * psc, int screen,
    psc->ext_list_first_time = GL_TRUE;
 
    if (!DRI2Connect(psc->dpy, RootWindow(psc->dpy, screen),
-                    &driverName, &deviceName))
+		    &driverName, &deviceName))
       return NULL;
 
    psc->driver = driOpenDriver(driverName);
@@ -481,9 +502,9 @@ dri2CreateScreen(__GLXscreenConfigs * psc, int screen,
 
    for (i = 0; extensions[i]; i++) {
       if (strcmp(extensions[i]->name, __DRI_CORE) == 0)
-         psc->core = (__DRIcoreExtension *) extensions[i];
+	 psc->core = (__DRIcoreExtension *) extensions[i];
       if (strcmp(extensions[i]->name, __DRI_DRI2) == 0)
-         psc->dri2 = (__DRIdri2Extension *) extensions[i];
+	 psc->dri2 = (__DRIdri2Extension *) extensions[i];
    }
 
    if (psc->core == NULL || psc->dri2 == NULL) {
@@ -512,16 +533,17 @@ dri2CreateScreen(__GLXscreenConfigs * psc, int screen,
     */
    psc->__driScreen =
       psc->dri2->createNewScreen(screen, psc->fd, ((pdp->driMinor < 1)
-                                                   ? loader_extensions_old
-                                                   : loader_extensions),
-                                 &driver_configs, psc);
+						   ? loader_extensions_old
+						   : loader_extensions),
+				 &driver_configs, psc);
 
    if (psc->__driScreen == NULL) {
       ErrorMessageF("failed to create dri screen\n");
       return NULL;
    }
 
-   driBindExtensions(psc, 1);
+   driBindCommonExtensions(psc);
+   dri2BindExtensions(psc);
 
    psc->configs = driConvertConfigs(psc->core, psc->configs, driver_configs);
    psc->visuals = driConvertConfigs(psc->core, psc->visuals, driver_configs);
@@ -534,6 +556,9 @@ dri2CreateScreen(__GLXscreenConfigs * psc, int screen,
    psp->swapBuffers = dri2SwapBuffers;
    psp->waitGL = dri2WaitGL;
    psp->waitX = dri2WaitX;
+   psp->getDrawableMSC = dri2DrawableGetMSC;
+   psp->waitForMSC = dri2WaitForMSC;
+   psp->waitForSBC = dri2WaitForSBC;
 
    /* DRI2 suports SubBuffer through DRI2CopyRegion, so it's always
     * available.*/
@@ -545,7 +570,7 @@ dri2CreateScreen(__GLXscreenConfigs * psc, int screen,
 
    return psp;
 
- handle_error:
+handle_error:
    Xfree(driverName);
    Xfree(deviceName);
 
diff --git a/src/glx/x11/dri_common.c b/src/glx/x11/dri_common.c
index 9c825ad74a..a94c752194 100644
--- a/src/glx/x11/dri_common.c
+++ b/src/glx/x11/dri_common.c
@@ -336,8 +336,9 @@ driConvertConfigs(const __DRIcoreExtension * core,
    return head.next;
 }
 
+/* Bind DRI1 specific extensions */
 _X_HIDDEN void
-driBindExtensions(__GLXscreenConfigs * psc, int dri2)
+driBindExtensions(__GLXscreenConfigs *psc)
 {
    const __DRIextension **extensions;
    int i;
@@ -345,35 +346,13 @@ driBindExtensions(__GLXscreenConfigs * psc, int dri2)
    extensions = psc->core->getExtensions(psc->__driScreen);
 
    for (i = 0; extensions[i]; i++) {
-#ifdef __DRI_COPY_SUB_BUFFER
-      if (strcmp(extensions[i]->name, __DRI_COPY_SUB_BUFFER) == 0) {
-         psc->driCopySubBuffer =
-            (__DRIcopySubBufferExtension *) extensions[i];
-         __glXEnableDirectExtension(psc, "GLX_MESA_copy_sub_buffer");
-      }
-#endif
-
 #ifdef __DRI_SWAP_CONTROL
       /* No DRI2 support for swap_control at the moment, since SwapBuffers
        * is done by the X server */
-      if (strcmp(extensions[i]->name, __DRI_SWAP_CONTROL) == 0 && !dri2) {
-         psc->swapControl = (__DRIswapControlExtension *) extensions[i];
-         __glXEnableDirectExtension(psc, "GLX_SGI_swap_control");
-         __glXEnableDirectExtension(psc, "GLX_MESA_swap_control");
-      }
-#endif
-
-#ifdef __DRI_ALLOCATE
-      if (strcmp(extensions[i]->name, __DRI_ALLOCATE) == 0) {
-         psc->allocate = (__DRIallocateExtension *) extensions[i];
-         __glXEnableDirectExtension(psc, "GLX_MESA_allocate_memory");
-      }
-#endif
-
-#ifdef __DRI_FRAME_TRACKING
-      if (strcmp(extensions[i]->name, __DRI_FRAME_TRACKING) == 0) {
-         psc->frameTracking = (__DRIframeTrackingExtension *) extensions[i];
-         __glXEnableDirectExtension(psc, "GLX_MESA_swap_frame_usage");
+      if (strcmp(extensions[i]->name, __DRI_SWAP_CONTROL) == 0) {
+	 psc->swapControl = (__DRIswapControlExtension *) extensions[i];
+	 __glXEnableDirectExtension(psc, "GLX_SGI_swap_control");
+	 __glXEnableDirectExtension(psc, "GLX_MESA_swap_control");
       }
 #endif
 
@@ -390,23 +369,77 @@ driBindExtensions(__GLXscreenConfigs * psc, int dri2)
        * GLX_OML_sync_control if implemented. */
 #endif
 
-#ifdef __DRI_READ_DRAWABLE
-      if (strcmp(extensions[i]->name, __DRI_READ_DRAWABLE) == 0) {
-         __glXEnableDirectExtension(psc, "GLX_SGI_make_current_read");
+      /* Ignore unknown extensions */
+   }
+}
+
+/* Bind DRI2 specific extensions */
+_X_HIDDEN void
+dri2BindExtensions(__GLXscreenConfigs *psc)
+{
+   const __DRIextension **extensions;
+   int i;
+
+   extensions = psc->core->getExtensions(psc->__driScreen);
+
+   for (i = 0; extensions[i]; i++) {
+#ifdef __DRI_TEX_BUFFER
+      if ((strcmp(extensions[i]->name, __DRI_TEX_BUFFER) == 0)) {
+	 psc->texBuffer = (__DRItexBufferExtension *) extensions[i];
+	 __glXEnableDirectExtension(psc, "GLX_EXT_texture_from_pixmap");
       }
 #endif
 
-#ifdef __DRI_TEX_BUFFER
-      if ((strcmp(extensions[i]->name, __DRI_TEX_BUFFER) == 0) && dri2) {
-         psc->texBuffer = (__DRItexBufferExtension *) extensions[i];
-         __glXEnableDirectExtension(psc, "GLX_EXT_texture_from_pixmap");
+#ifdef __DRI2_MEDIA_STREAM_COUNTER
+      if (strcmp(extensions[i]->name, __DRI2_MEDIA_STREAM_COUNTER) == 0) {
+	 psc->msc = (__DRI2mediaStreamCounterExtension *) extensions[i];
+	 __glXEnableDirectExtension(psc, "GLX_SGI_video_sync");
       }
 #endif
 
 #ifdef __DRI2_FLUSH
-      if ((strcmp(extensions[i]->name, __DRI2_FLUSH) == 0) && dri2) {
-         psc->f = (__DRI2flushExtension *) extensions[i];
-         /* internal driver extension, no GL extension exposed */
+      if ((strcmp(extensions[i]->name, __DRI2_FLUSH) == 0)) {
+	 psc->f = (__DRI2flushExtension *) extensions[i];
+	 /* internal driver extension, no GL extension exposed */
+      }
+#endif
+   }
+}
+
+/* Bind extensions common to DRI1 and DRI2 */
+_X_HIDDEN void
+driBindCommonExtensions(__GLXscreenConfigs *psc)
+{
+   const __DRIextension **extensions;
+   int i;
+
+   extensions = psc->core->getExtensions(psc->__driScreen);
+
+   for (i = 0; extensions[i]; i++) {
+#ifdef __DRI_COPY_SUB_BUFFER
+      if (strcmp(extensions[i]->name, __DRI_COPY_SUB_BUFFER) == 0) {
+	 psc->driCopySubBuffer = (__DRIcopySubBufferExtension *) extensions[i];
+	 __glXEnableDirectExtension(psc, "GLX_MESA_copy_sub_buffer");
+      }
+#endif
+
+#ifdef __DRI_ALLOCATE
+      if (strcmp(extensions[i]->name, __DRI_ALLOCATE) == 0) {
+	 psc->allocate = (__DRIallocateExtension *) extensions[i];
+	 __glXEnableDirectExtension(psc, "GLX_MESA_allocate_memory");
+      }
+#endif
+
+#ifdef __DRI_FRAME_TRACKING
+      if (strcmp(extensions[i]->name, __DRI_FRAME_TRACKING) == 0) {
+	 psc->frameTracking = (__DRIframeTrackingExtension *) extensions[i];
+	 __glXEnableDirectExtension(psc, "GLX_MESA_swap_frame_usage");
+      }
+#endif
+
+#ifdef __DRI_READ_DRAWABLE
+      if (strcmp(extensions[i]->name, __DRI_READ_DRAWABLE) == 0) {
+	 __glXEnableDirectExtension(psc, "GLX_SGI_make_current_read");
       }
 #endif
 
diff --git a/src/glx/x11/dri_common.h b/src/glx/x11/dri_common.h
index 61ac9c6416..bb178db787 100644
--- a/src/glx/x11/dri_common.h
+++ b/src/glx/x11/dri_common.h
@@ -56,6 +56,8 @@ extern void ErrorMessageF(const char *f, ...);
 
 extern void *driOpenDriver(const char *driverName);
 
-extern void driBindExtensions(__GLXscreenConfigs * psc, int dri2);
+extern void driBindExtensions(__GLXscreenConfigs * psc);
+extern void dri2BindExtensions(__GLXscreenConfigs * psc);
+extern void driBindCommonExtensions(__GLXscreenConfigs * psc);
 
 #endif /* _DRI_COMMON_H */
diff --git a/src/glx/x11/dri_glx.c b/src/glx/x11/dri_glx.c
index 4f7acb6cc3..42cb25304e 100644
--- a/src/glx/x11/dri_glx.c
+++ b/src/glx/x11/dri_glx.c
@@ -620,10 +620,12 @@ driCreateDrawable(__GLXscreenConfigs * psc,
    return pdraw;
 }
 
-static void
-driSwapBuffers(__GLXDRIdrawable * pdraw)
+static int64_t
+driSwapBuffers(__GLXDRIdrawable * pdraw, int64_t unused1, int64_t unused2,
+	       int64_t unused3)
 {
    (*pdraw->psc->core->swapBuffers) (pdraw->driDrawable);
+   return 0;
 }
 
 static void
@@ -683,9 +685,9 @@ driCreateScreen(__GLXscreenConfigs * psc, int screen,
 
    for (i = 0; extensions[i]; i++) {
       if (strcmp(extensions[i]->name, __DRI_CORE) == 0)
-         psc->core = (__DRIcoreExtension *) extensions[i];
+	 psc->core = (__DRIcoreExtension *) extensions[i];
       if (strcmp(extensions[i]->name, __DRI_LEGACY) == 0)
-         psc->legacy = (__DRIlegacyExtension *) extensions[i];
+	 psc->legacy = (__DRIlegacyExtension *) extensions[i];
    }
 
    if (psc->core == NULL || psc->legacy == NULL) {
@@ -701,7 +703,9 @@ driCreateScreen(__GLXscreenConfigs * psc, int screen,
       return NULL;
    }
 
-   driBindExtensions(psc, 0);
+   driBindExtensions(psc);
+   driBindCommonExtensions(psc);
+
    if (psc->driCopySubBuffer)
       psp->copySubBuffer = driCopySubBuffer;
 
diff --git a/src/glx/x11/drisw_glx.c b/src/glx/x11/drisw_glx.c
index 1866b2cc87..6a51d748af 100644
--- a/src/glx/x11/drisw_glx.c
+++ b/src/glx/x11/drisw_glx.c
@@ -398,7 +398,8 @@ driCreateScreen(__GLXscreenConfigs * psc, int screen,
       goto handle_error;
    }
 
-   driBindExtensions(psc, 0);
+   driBindExtensions(psc);
+   driBindCommonExtensions(psc);
 
    psc->configs = driConvertConfigs(psc->core, psc->configs, driver_configs);
    psc->visuals = driConvertConfigs(psc->core, psc->visuals, driver_configs);
diff --git a/src/glx/x11/glxclient.h b/src/glx/x11/glxclient.h
index 00ee14fb05..2b835a0a9c 100644
--- a/src/glx/x11/glxclient.h
+++ b/src/glx/x11/glxclient.h
@@ -121,26 +121,33 @@ struct __GLXDRIdisplayRec
                                     __GLXdisplayPrivate * priv);
 };
 
-struct __GLXDRIscreenRec
-{
-
-   void (*destroyScreen) (__GLXscreenConfigs * psc);
-
-   __GLXDRIcontext *(*createContext) (__GLXscreenConfigs * psc,
-                                      const __GLcontextModes * mode,
-                                      GLXContext gc,
-                                      GLXContext shareList, int renderType);
-
-   __GLXDRIdrawable *(*createDrawable) (__GLXscreenConfigs * psc,
-                                        XID drawable,
-                                        GLXDrawable glxDrawable,
-                                        const __GLcontextModes * modes);
-
-   void (*swapBuffers) (__GLXDRIdrawable * pdraw);
-   void (*copySubBuffer) (__GLXDRIdrawable * pdraw,
-                          int x, int y, int width, int height);
-   void (*waitX) (__GLXDRIdrawable * pdraw);
-   void (*waitGL) (__GLXDRIdrawable * pdraw);
+struct __GLXDRIscreenRec {
+
+   void (*destroyScreen)(__GLXscreenConfigs *psc);
+
+   __GLXDRIcontext *(*createContext)(__GLXscreenConfigs *psc,
+				     const __GLcontextModes *mode,
+				     GLXContext gc,
+				     GLXContext shareList, int renderType);
+
+   __GLXDRIdrawable *(*createDrawable)(__GLXscreenConfigs *psc,
+				       XID drawable,
+				       GLXDrawable glxDrawable,
+				       const __GLcontextModes *modes);
+
+   int64_t (*swapBuffers)(__GLXDRIdrawable *pdraw, int64_t target_msc,
+			  int64_t divisor, int64_t remainder);
+   void (*copySubBuffer)(__GLXDRIdrawable *pdraw,
+			 int x, int y, int width, int height);
+   void (*waitX)(__GLXDRIdrawable *pdraw);
+   void (*waitGL)(__GLXDRIdrawable *pdraw);
+   int (*getDrawableMSC)(__GLXscreenConfigs *psc, __GLXDRIdrawable *pdraw,
+			 int64_t *ust, int64_t *msc, int64_t *sbc);
+   int (*waitForMSC)(__GLXDRIdrawable *pdraw, int64_t target_msc,
+		     int64_t divisor, int64_t remainder, int64_t *ust,
+		     int64_t *msc, int64_t *sbc);
+   int (*waitForSBC)(__GLXDRIdrawable *pdraw, int64_t target_sbc, int64_t *ust,
+		     int64_t *msc, int64_t *sbc);
 };
 
 struct __GLXDRIcontextRec
diff --git a/src/glx/x11/glxcmds.c b/src/glx/x11/glxcmds.c
index daa9076471..c7ccaaa0b5 100644
--- a/src/glx/x11/glxcmds.c
+++ b/src/glx/x11/glxcmds.c
@@ -982,7 +982,7 @@ glXSwapBuffers(Display * dpy, GLXDrawable drawable)
 
    if (pdraw != NULL) {
       glFlush();
-      (*pdraw->psc->driScreen->swapBuffers) (pdraw);
+      (*pdraw->psc->driScreen->swapBuffers)(pdraw, 0, 0, 0);
       return;
    }
 #endif
@@ -1898,17 +1898,17 @@ __glXSwapIntervalSGI(int interval)
 
 #ifdef __DRI_SWAP_CONTROL
    if (gc->driContext) {
-      __GLXscreenConfigs *const psc = GetGLXScreenConfigs(gc->currentDpy,
-                                                          gc->screen);
+      __GLXscreenConfigs * const psc = GetGLXScreenConfigs( gc->currentDpy,
+							    gc->screen );
       __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(gc->currentDpy,
-                                                  gc->currentDrawable,
-                                                  NULL);
+						  gc->currentDrawable,
+						  NULL);
       if (psc->swapControl != NULL && pdraw != NULL) {
-         psc->swapControl->setSwapInterval(pdraw->driDrawable, interval);
-         return 0;
+	 psc->swapControl->setSwapInterval(pdraw->driDrawable, interval);
+	 return 0;
       }
-      else {
-         return GLX_BAD_CONTEXT;
+      else if (pdraw == NULL) {
+	 return GLX_BAD_CONTEXT;
       }
    }
 #endif
@@ -2102,64 +2102,73 @@ __glXQueryFrameTrackingMESA(Display * dpy, GLXDrawable drawable,
 static int
 __glXGetVideoSyncSGI(unsigned int *count)
 {
+   int64_t ust, msc, sbc;
+   int ret;
+   GLXContext gc = __glXGetCurrentContext();
+   __GLXscreenConfigs *psc;
+   __GLXDRIdrawable *pdraw;
+
+   if (!gc || !gc->driContext)
+      return GLX_BAD_CONTEXT;
+
+   psc = GetGLXScreenConfigs(gc->currentDpy, gc->screen);
+   pdraw = GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
+
    /* FIXME: Looking at the GLX_SGI_video_sync spec in the extension registry,
     * FIXME: there should be a GLX encoding for this call.  I can find no
     * FIXME: documentation for the GLX encoding.
     */
 #ifdef __DRI_MEDIA_STREAM_COUNTER
-   GLXContext gc = __glXGetCurrentContext();
+   if ( psc->msc && psc->driScreen ) {
+      ret = (*psc->msc->getDrawableMSC)(psc->__driScreen,
+					pdraw->driDrawable, &msc);
+      *count = (unsigned) msc;
 
-
-   if (gc != NULL && gc->driContext) {
-      __GLXscreenConfigs *const psc = GetGLXScreenConfigs(gc->currentDpy,
-                                                          gc->screen);
-      if (psc->msc && psc->driScreen) {
-         __GLXDRIdrawable *pdraw =
-            GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
-         int64_t temp;
-         int ret;
-
-         ret = (*psc->msc->getDrawableMSC) (psc->__driScreen,
-                                            pdraw->driDrawable, &temp);
-         *count = (unsigned) temp;
-
-         return (ret == 0) ? 0 : GLX_BAD_CONTEXT;
-      }
+      return (ret == 0) ? 0 : GLX_BAD_CONTEXT;
    }
-#else
-   (void) count;
 #endif
+   if (psc->driScreen && psc->driScreen->getDrawableMSC) {
+      ret = psc->driScreen->getDrawableMSC(psc, pdraw, &ust, &msc, &sbc);
+      *count = (unsigned) msc;
+      return (ret == True) ? 0 : GLX_BAD_CONTEXT;
+   }
+
    return GLX_BAD_CONTEXT;
 }
 
 static int
 __glXWaitVideoSyncSGI(int divisor, int remainder, unsigned int *count)
 {
-#ifdef __DRI_MEDIA_STREAM_COUNTER
    GLXContext gc = __glXGetCurrentContext();
+   __GLXscreenConfigs *psc;
+   __GLXDRIdrawable *pdraw;
+   int64_t ust, msc, sbc;
+   int ret;
 
    if (divisor <= 0 || remainder < 0)
       return GLX_BAD_VALUE;
 
-   if (gc != NULL && gc->driContext) {
-      __GLXscreenConfigs *const psc = GetGLXScreenConfigs(gc->currentDpy,
-                                                          gc->screen);
-      if (psc->msc != NULL && psc->driScreen) {
-         __GLXDRIdrawable *pdraw =
-            GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
-         int ret;
-         int64_t msc;
-         int64_t sbc;
-
-         ret = (*psc->msc->waitForMSC) (pdraw->driDrawable, 0,
-                                        divisor, remainder, &msc, &sbc);
-         *count = (unsigned) msc;
-         return (ret == 0) ? 0 : GLX_BAD_CONTEXT;
-      }
+   if (!gc || !gc->driContext)
+      return GLX_BAD_CONTEXT;
+
+   psc = GetGLXScreenConfigs( gc->currentDpy, gc->screen);
+   pdraw = GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable, NULL);
+
+#ifdef __DRI_MEDIA_STREAM_COUNTER
+   if (psc->msc != NULL && psc->driScreen ) {
+      ret = (*psc->msc->waitForMSC)(pdraw->driDrawable, 0,
+				    divisor, remainder, &msc, &sbc);
+      *count = (unsigned) msc;
+      return (ret == 0) ? 0 : GLX_BAD_CONTEXT;
    }
-#else
-   (void) count;
 #endif
+   if (psc->driScreen && psc->driScreen->waitForMSC) {
+      ret = psc->driScreen->waitForMSC(pdraw, 0, divisor, remainder, &ust, &msc,
+				       &sbc);
+      *count = (unsigned) msc;
+      return (ret == True) ? 0 : GLX_BAD_CONTEXT;
+   }
+
    return GLX_BAD_CONTEXT;
 }
 
@@ -2312,27 +2321,29 @@ static Bool
 __glXGetSyncValuesOML(Display * dpy, GLXDrawable drawable,
                       int64_t * ust, int64_t * msc, int64_t * sbc)
 {
-#if defined(__DRI_SWAP_BUFFER_COUNTER) && defined(__DRI_MEDIA_STREAM_COUNTER)
-   __GLXdisplayPrivate *const priv = __glXInitialize(dpy);
+   __GLXdisplayPrivate * const priv = __glXInitialize(dpy);
+   int i, ret;
+   __GLXDRIdrawable *pdraw;
+   __GLXscreenConfigs *psc;
 
-   if (priv != NULL) {
-      int i;
-      __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &i);
-      __GLXscreenConfigs *const psc = &priv->screenConfigs[i];
+   if (!priv)
+      return False;
 
-      assert((pdraw == NULL) || (i != -1));
-      return ((pdraw && psc->sbc && psc->msc)
-              && ((*psc->msc->getMSC) (psc->driScreen, msc) == 0)
-              && ((*psc->sbc->getSBC) (pdraw->driDrawable, sbc) == 0)
-              && (__glXGetUST(ust) == 0));
-   }
-#else
-   (void) dpy;
-   (void) drawable;
-   (void) ust;
-   (void) msc;
-   (void) sbc;
+   pdraw = GetGLXDRIDrawable(dpy, drawable, &i);
+   psc = &priv->screenConfigs[i];
+
+#if defined(__DRI_SWAP_BUFFER_COUNTER) && defined(__DRI_MEDIA_STREAM_COUNTER)
+   if (pdraw && psc->sbc && psc->sbc)
+      return ( (pdraw && psc->sbc && psc->msc)
+	       && ((*psc->msc->getMSC)(psc->driScreen, msc) == 0)
+	       && ((*psc->sbc->getSBC)(pdraw->driDrawable, sbc) == 0)
+	       && (__glXGetUST(ust) == 0) );
 #endif
+   if (pdraw && psc && psc->driScreen && psc->driScreen->getDrawableMSC) {
+      ret = psc->driScreen->getDrawableMSC(psc, pdraw, ust, msc, sbc);
+      return ret;
+   }
+
    return False;
 }
 
@@ -2440,11 +2451,14 @@ static int64_t
 __glXSwapBuffersMscOML(Display * dpy, GLXDrawable drawable,
                        int64_t target_msc, int64_t divisor, int64_t remainder)
 {
-#ifdef __DRI_SWAP_BUFFER_COUNTER
+   GLXContext gc = __glXGetCurrentContext();
    int screen;
    __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
    __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
 
+   if (!pdraw || !gc->driContext) /* no GLX for this */
+      return -1;
+
    /* The OML_sync_control spec says these should "generate a GLX_BAD_VALUE
     * error", but it also says "It [glXSwapBuffersMscOML] will return a value
     * of -1 if the function failed because of errors detected in the input
@@ -2455,18 +2469,19 @@ __glXSwapBuffersMscOML(Display * dpy, GLXDrawable drawable,
    if (divisor > 0 && remainder >= divisor)
       return -1;
 
-   if (pdraw != NULL && psc->counters != NULL)
-      return (*psc->sbc->swapBuffersMSC) (pdraw->driDrawable, target_msc,
-                                          divisor, remainder);
+#ifdef __DRI_SWAP_BUFFER_COUNTER
+   if (psc->counters != NULL)
+      return (*psc->sbc->swapBuffersMSC)(pdraw->driDrawable, target_msc,
+					 divisor, remainder);
+#endif
 
-#else
-   (void) dpy;
-   (void) drawable;
-   (void) target_msc;
-   (void) divisor;
-   (void) remainder;
+#ifdef GLX_DIRECT_RENDERING
+   if (psc->driScreen && psc->driScreen->swapBuffers)
+      return (*psc->driScreen->swapBuffers)(pdraw, target_msc, divisor,
+					    remainder);
 #endif
-   return 0;
+
+   return -1;
 }
 
 
@@ -2476,12 +2491,14 @@ __glXWaitForMscOML(Display * dpy, GLXDrawable drawable,
                    int64_t remainder, int64_t * ust,
                    int64_t * msc, int64_t * sbc)
 {
-#ifdef __DRI_MEDIA_STREAM_COUNTER
-   int screen = 0;
+   int screen;
    __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
-   __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
+   __GLXscreenConfigs * const psc = GetGLXScreenConfigs( dpy, screen );
    int ret;
 
+   fprintf(stderr, "waitmsc: %lld, %lld, %lld\n", target_msc, divisor,
+	   remainder);
+
    /* The OML_sync_control spec says these should "generate a GLX_BAD_VALUE
     * error", but the return type in the spec is Bool.
     */
@@ -2490,7 +2507,9 @@ __glXWaitForMscOML(Display * dpy, GLXDrawable drawable,
    if (divisor > 0 && remainder >= divisor)
       return False;
 
+#ifdef __DRI_MEDIA_STREAM_COUNTER
    if (pdraw != NULL && psc->msc != NULL) {
+      fprintf(stderr, "dri1 msc\n");
       ret = (*psc->msc->waitForMSC) (pdraw->driDrawable, target_msc,
                                      divisor, remainder, msc, sbc);
 
@@ -2499,16 +2518,14 @@ __glXWaitForMscOML(Display * dpy, GLXDrawable drawable,
        */
       return ((ret == 0) && (__glXGetUST(ust) == 0));
    }
-#else
-   (void) dpy;
-   (void) drawable;
-   (void) target_msc;
-   (void) divisor;
-   (void) remainder;
-   (void) ust;
-   (void) msc;
-   (void) sbc;
 #endif
+   if (pdraw && psc->driScreen && psc->driScreen->waitForMSC) {
+      ret = psc->driScreen->waitForMSC(pdraw, target_msc, divisor, remainder,
+				       ust, msc, sbc);
+      return ret;
+   }
+
+   fprintf(stderr, "no drawable??\n");
    return False;
 }
 
@@ -2518,7 +2535,6 @@ __glXWaitForSbcOML(Display * dpy, GLXDrawable drawable,
                    int64_t target_sbc, int64_t * ust,
                    int64_t * msc, int64_t * sbc)
 {
-#ifdef __DRI_SWAP_BUFFER_COUNTER
    int screen;
    __GLXDRIdrawable *pdraw = GetGLXDRIDrawable(dpy, drawable, &screen);
    __GLXscreenConfigs *const psc = GetGLXScreenConfigs(dpy, screen);
@@ -2529,7 +2545,7 @@ __glXWaitForSbcOML(Display * dpy, GLXDrawable drawable,
     */
    if (target_sbc < 0)
       return False;
-
+#ifdef __DRI_SWAP_BUFFER_COUNTER
    if (pdraw != NULL && psc->sbc != NULL) {
       ret =
          (*psc->sbc->waitForSBC) (pdraw->driDrawable, target_sbc, msc, sbc);
@@ -2539,14 +2555,11 @@ __glXWaitForSbcOML(Display * dpy, GLXDrawable drawable,
        */
       return ((ret == 0) && (__glXGetUST(ust) == 0));
    }
-#else
-   (void) dpy;
-   (void) drawable;
-   (void) target_sbc;
-   (void) ust;
-   (void) msc;
-   (void) sbc;
 #endif
+   if (pdraw && psc->driScreen && psc->driScreen->waitForMSC) {
+      ret = psc->driScreen->waitForSBC(pdraw, target_sbc, ust, msc, sbc);
+      return ret;
+   }
    return False;
 }