| Message ID | 1310039291-22554-5-git-send-email-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 8ff0eae..ea085ff 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -6131,6 +6131,7 @@ static void intel_unpin_work_fn(struct work_struct *__work) drm_gem_object_unreference(&work->pending_flip_obj->base); drm_gem_object_unreference(&work->old_fb_obj->base); + intel_update_fbc(work->dev); mutex_unlock(&work->dev->struct_mutex); kfree(work); } @@ -6495,6 +6496,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, if (ret) goto cleanup_pending; + intel_disable_fbc(dev); mutex_unlock(&dev->struct_mutex); trace_i915_flip_request(intel_crtc->plane, obj);
Page-flipping updates the scanout address, nukes the FBC compressed image and so forces an FBC update so that the displayed image remains consistent. However, page-flipping does not update the FBC registers themselves, which remain pointing to both the old address and the old CPU fence. Future updates to the new front-buffer (scanout) are then undetected! This first approach to demonstrate the issue and highlight the fix, simply disables FBC upon page-flip (a recompression will be forced on every flip so FBC becomes immaterial) and then re-enables FBC in the page-flip finish work function, so that the FBC registers are now pointing to the new framebuffer and front-buffer rendering works once more. Ideally, we want to only re-enable FBC after page-flipping is complete, as otherwise we are just wasting cycles (along with an undesirable wait-for-vblank which will halve the frame-rate of vsync'ed games) and power (with needless recompression) whilst the page-flipping application is still running. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=33487 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/intel_display.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)