i915tex: Wait for pending scheduled flips before switching vsync pipe.

This avoids hangs when the vblank sequence numbers are not in sync between
pipes, in particular when they run at different refresh rates.

diff --git a/src/mesa/drivers/dri/i915tex/intel_buffers.c b/src/mesa/drivers/dri/i915tex/intel_buffers.c
index 174f3c6351a8ce2b4750aa17a6593978c085711c..164395719cd4f2c0276c75cbdcad4e1940243902 100644 (file)
--- a/src/mesa/drivers/dri/i915tex/intel_buffers.c
+++ b/src/mesa/drivers/dri/i915tex/intel_buffers.c
@@ -300,8 +300,27 @@ intelWindowMoved(struct intel_context *intel)
       }
 
       if (flags != intel_fb->vblank_flags) {
+        drmVBlank vbl;
+        int i;
+
+        vbl.request.type = DRM_VBLANK_ABSOLUTE;
+
+        if ( intel_fb->vblank_flags & VBLANK_FLAG_SECONDARY ) {
+           vbl.request.type |= DRM_VBLANK_SECONDARY;
+        }
+
+        for (i = 0; i < intel_fb->pf_num_pages; i++) {
+           vbl.request.sequence = intel_fb->color_rb[i]->vbl_pending;
+           drmWaitVBlank(intel->driFd, &vbl);
+        }
+
         intel_fb->vblank_flags = flags;
         driGetCurrentVBlank(dPriv, intel_fb->vblank_flags, &intel_fb->vbl_seq);
+        intel_fb->vbl_waited = intel_fb->vbl_seq;
+
+        for (i = 0; i < intel_fb->pf_num_pages; i++) {
+           intel_fb->color_rb[i]->vbl_pending = intel_fb->vbl_waited;
+        }
       }
    } else {
       intel_fb->vblank_flags &= ~VBLANK_FLAG_SECONDARY;