xf86-video-intel: src/uxa/intel_dri.c src/uxa/intel.h

[Chris Wilson]

 src/uxa/intel.h     |    5 +++++
 src/uxa/intel_dri.c |   13 ++++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

New commits:
commit 70cb682662f9c54bcc7cc0eda029c21efbb4947f
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Mon Feb 2 10:03:33 2015 +0000

    uxa/dri2: Recreate the triple buffer across a mode change
    
    If the mode changes whilst we have a pending flip, we may reinstall the
    previous scanout buffer as our next back buffer despite it no longer
    matching.
    
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

diff --git a/src/uxa/intel.h b/src/uxa/intel.h
index 55f74e5..37b23e9 100644
--- a/src/uxa/intel.h
+++ b/src/uxa/intel.h
@@ -415,6 +415,11 @@ typedef struct _DRI2FrameEvent {
 	DRI2BufferPtr front;
 	DRI2BufferPtr back;
 
+	/* current scanout for triple buffer */
+	int old_width;
+	int old_height;
+	int old_pitch;
+	int old_tiling;
 	dri_bo *old_buffer;
 } DRI2FrameEventRec, *DRI2FrameEventPtr;
 
diff --git a/src/uxa/intel_dri.c b/src/uxa/intel_dri.c
index 481782f..32622ad 100644
--- a/src/uxa/intel_dri.c
+++ b/src/uxa/intel_dri.c
@@ -709,7 +709,14 @@ i830_dri2_del_frame_event(DRI2FrameEventPtr info)
 		I830DRI2DestroyBuffer(NULL, info->back);
 
 	if (info->old_buffer) {
-		if (info->intel->back_buffer == NULL)
+		/* Check that the old buffer still matches the front buffer
+		 * in case a mode change occurred before we woke up.
+		 */
+		if (info->intel->back_buffer == NULL &&
+		    info->old_width  == info->intel->scrn->virtualX &&
+		    info->old_height == info->intel->scrn->virtualY &&
+		    info->old_pitch  == info->intel->front_pitch &&
+		    info->old_tiling == info->intel->front_tiling)
 			info->intel->back_buffer = info->old_buffer;
 		else
 			dri_bo_unreference(info->old_buffer);
@@ -895,6 +902,10 @@ queue_flip(struct intel_screen_private *intel,
 
 #if DRI2INFOREC_VERSION >= 6
 	if (intel->use_triple_buffer && allocate_back_buffer(intel)) {
+		info->old_width  = intel->scrn->virtualX;
+		info->old_height = intel->scrn->virtualY;
+		info->old_pitch  = intel->front_pitch;
+		info->old_tiling = intel->front_tiling;
 		info->old_buffer = intel->front_buffer;
 		dri_bo_reference(info->old_buffer);