Refactor and fix core vblank support

Consolidate support for synchronizing to and retrieving vblank counters.  Also
fix the core vblank code to return monotonic MSC counters, which are required
by some GLX extensions.  Adding support for multiple pipes to a low level
driver is fairly easy, the Intel 965 driver provides simple example code (see
intel_buffers.c:intelWindowMoved()).

The new code bumps the media stream counter extension version to 2 and adds a
new getDrawableMSC callback.  This callback takes a drawablePrivate pointer,
which is used to calculate the MSC value seen by clients based on the actual
vblank counter(s) returned from the kernel.  The new drawable private fields
are as follows:
  - vblSeq - used for tracking vblank counts for buffer swapping
  - vblFlags - flags (e.g. current pipe), updated by low level driver
  - msc_base - MSC counter from the last time the current pipe changed
  - vblank_base - kernel DRM vblank counter from the last time the pipe changed

Using the above variables, the core vblank code (in vblank.c) can calculate a
monotonic MSC value.  The low level DRI drivers are responsible for updating
the current pipe (by setting VBLANK_FLAG_SECONDARY for example in vblFlags)
along with msc_base and vblank_base whenever the pipe associated with a given
drawable changes (again, see intelWindowMoved for an example of this).

Drivers should fill in the GetDrawableMSC DriverAPIRec field to point to
driDrawableGetMSC32 and add code for pipe switching as outlined above to fully
support the new scheme.

5 files changed, 13 insertions, 15 deletions

diff --git a/src/mesa/drivers/dri/unichrome/via_context.c b/src/mesa/drivers/dri/unichrome/via_context.c
index 66e92cc..5d95d97 100644
--- a/src/mesa/drivers/dri/unichrome/via_context.c
+++ b/src/mesa/drivers/dri/unichrome/via_context.c
@@ -465,6 +465,7 @@ viaCreateContext(const __GLcontextModes *visual,
     GLcontext *ctx, *shareCtx;
     struct via_context *vmesa;
     __DRIscreenPrivate *sPriv = driContextPriv->driScreenPriv;
+    __DRIdrawablePrivate *dPriv = driContextPriv->driDrawablePriv;
     viaScreenPrivate *viaScreen = (viaScreenPrivate *)sPriv->private;
     drm_via_sarea_t *saPriv = (drm_via_sarea_t *)
         (((GLubyte *)sPriv->pSAREA) + viaScreen->sareaPrivOffset);
@@ -658,7 +659,7 @@ viaCreateContext(const __GLcontextModes *visual,
         driQueryOptionb(&vmesa->optionCache, "no_rast"))
        FALLBACK(vmesa, VIA_FALLBACK_USER_DISABLE, 1);
 
-    vmesa->vblank_flags =
+    dPriv->vblFlags =
        vmesa->viaScreen->irqEnabled ?
         driGetDefaultVBlankFlags(&vmesa->optionCache) : VBLANK_FLAG_NO_IRQ;
 
@@ -838,8 +839,7 @@ viaMakeCurrent(__DRIcontextPrivate *driContextPriv,
         readBuffer = (GLframebuffer *)driReadPriv->driverPrivate;
 
 	if (vmesa->driDrawable != driDrawPriv) {
-	   driDrawableInitVBlank(driDrawPriv, vmesa->vblank_flags,
-				 &vmesa->vbl_seq);
+	    driDrawableInitVBlank(driDrawPriv);
 	}
 
        if ((vmesa->driDrawable != driDrawPriv)
diff --git a/src/mesa/drivers/dri/unichrome/via_context.h b/src/mesa/drivers/dri/unichrome/via_context.h
index 6321713..acd6f2e 100644
--- a/src/mesa/drivers/dri/unichrome/via_context.h
+++ b/src/mesa/drivers/dri/unichrome/via_context.h
@@ -321,9 +321,6 @@ struct via_context {
     */
    driOptionCache optionCache;
 
-   GLuint vblank_flags;
-   GLuint vbl_seq;
-
    int64_t swap_ust;
    int64_t swap_missed_ust;
 
diff --git a/src/mesa/drivers/dri/unichrome/via_ioctl.c b/src/mesa/drivers/dri/unichrome/via_ioctl.c
index 4a733fb..3c7dafd 100644
--- a/src/mesa/drivers/dri/unichrome/via_ioctl.c
+++ b/src/mesa/drivers/dri/unichrome/via_ioctl.c
@@ -507,7 +507,7 @@ void viaWaitIdleLocked( struct via_context *vmesa, GLboolean light )
  * except that WAIT_IDLE() will spin the CPU polling, while this is
  * IRQ driven.
  */
-static void viaWaitIdleVBlank( const __DRIdrawablePrivate *dPriv, 
+static void viaWaitIdleVBlank(  __DRIdrawablePrivate *dPriv, 
 			       struct via_context *vmesa,
 			       GLuint value )
 {
@@ -523,8 +523,8 @@ static void viaWaitIdleVBlank( const __DRIdrawablePrivate *dPriv,
 	  vmesa->thrashing)
 	 viaSwapOutWork(vmesa);
 
-      driWaitForVBlank( dPriv, & vmesa->vbl_seq, 
-			vmesa->vblank_flags, & missed_target );
+      driWaitForVBlank( dPriv, & dPriv->vblSeq, dPriv->vblFlags,
+			& missed_target );
       if ( missed_target ) {
 	 vmesa->swap_missed_count++;
 	 (*dri_interface->getUST)( &vmesa->swap_missed_ust );
@@ -591,7 +591,7 @@ void viaResetPageFlippingLocked(struct via_context *vmesa)
 /*
  * Copy the back buffer to the front buffer. 
  */
-void viaCopyBuffer(const __DRIdrawablePrivate *dPriv)
+void viaCopyBuffer(__DRIdrawablePrivate *dPriv)
 {
    struct via_context *vmesa = 
       (struct via_context *)dPriv->driContextPriv->driverPrivate;
@@ -607,7 +607,7 @@ void viaCopyBuffer(const __DRIdrawablePrivate *dPriv)
 
    VIA_FLUSH_DMA(vmesa);
 
-   if (vmesa->vblank_flags == VBLANK_FLAG_SYNC &&
+   if (dPriv->vblFlags == VBLANK_FLAG_SYNC &&
        vmesa->lastBreadcrumbWrite > 1)
       viaWaitIdleVBlank(dPriv, vmesa, vmesa->lastBreadcrumbWrite-1);
    else
@@ -634,14 +634,14 @@ void viaCopyBuffer(const __DRIdrawablePrivate *dPriv)
 }
 
 
-void viaPageFlip(const __DRIdrawablePrivate *dPriv)
+void viaPageFlip(__DRIdrawablePrivate *dPriv)
 {
     struct via_context *vmesa = 
        (struct via_context *)dPriv->driContextPriv->driverPrivate;
     struct via_renderbuffer buffer_tmp;
 
     VIA_FLUSH_DMA(vmesa);
-   if (vmesa->vblank_flags == VBLANK_FLAG_SYNC &&
+   if (dPriv->vblFlags == VBLANK_FLAG_SYNC &&
        vmesa->lastBreadcrumbWrite > 1)
       viaWaitIdleVBlank(dPriv, vmesa, vmesa->lastBreadcrumbWrite - 1);
    else
diff --git a/src/mesa/drivers/dri/unichrome/via_ioctl.h b/src/mesa/drivers/dri/unichrome/via_ioctl.h
index a81b427..44fc439 100644
--- a/src/mesa/drivers/dri/unichrome/via_ioctl.h
+++ b/src/mesa/drivers/dri/unichrome/via_ioctl.h
@@ -33,8 +33,8 @@ void viaFlushDma(struct via_context *vmesa);
 void viaFlushDmaLocked(struct via_context *vmesa, GLuint flags);
 
 void viaInitIoctlFuncs(GLcontext *ctx);
-void viaCopyBuffer(const __DRIdrawablePrivate *dpriv);
-void viaPageFlip(const __DRIdrawablePrivate *dpriv);
+void viaCopyBuffer(__DRIdrawablePrivate *dpriv);
+void viaPageFlip(__DRIdrawablePrivate *dpriv);
 void viaCheckDma(struct via_context *vmesa, GLuint bytes);
 void viaResetPageFlippingLocked(struct via_context *vmesa);
 void viaWaitIdle(struct via_context *vmesa, GLboolean light);
diff --git a/src/mesa/drivers/dri/unichrome/via_screen.c b/src/mesa/drivers/dri/unichrome/via_screen.c
index f3912ac..0ad18b4 100644
--- a/src/mesa/drivers/dri/unichrome/via_screen.c
+++ b/src/mesa/drivers/dri/unichrome/via_screen.c
@@ -334,6 +334,7 @@ static struct __DriverAPIRec viaAPI = {
    .UnbindContext   = viaUnbindContext,
    .GetSwapInfo     = getSwapInfo,
    .GetMSC          = driGetMSC32,
+   .GetDrawableMSC  = driDrawableGetMSC32,
    .WaitForMSC      = driWaitForMSC32,
    .WaitForSBC      = NULL,
    .SwapBuffersMSC  = NULL