3.6-stable review patch. If anyone has any objections, please let me know.
------------------ From: Chris Wilson <[email protected]> commit 5bb61643f6a70d48de9cfe91ad0fee0d618b6816 upstream. This was meant to be the purpose of the intel_crtc_wait_for_pending_flips() function which is called whilst preparing the CRTC for a modeset or before disabling. However, as Ville Syrjala pointed out, we set the pending flip notification on the old framebuffer that is no longer attached to the CRTC by the time we come to flush the pending operations. Instead, we can simply wait on the pending unpin work to be finished on this CRTC, knowning that the hardware has therefore finished modifying the registers, before proceeding with our direct access. Fixes i-g-t/flip_test on non-pch platforms. pch platforms simply schedule the flip immediately when the pipe is disabled, leading to other funny issues. Signed-off-by: Chris Wilson <[email protected]> [danvet: Added i-g-t note and cc: stable] Signed-off-by: Daniel Vetter <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/gpu/drm/i915/intel_display.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2823,13 +2823,34 @@ static void ironlake_fdi_disable(struct udelay(100); } +static bool intel_crtc_has_pending_flip(struct drm_crtc *crtc) +{ + struct drm_device *dev = crtc->dev; + struct drm_i915_private *dev_priv = dev->dev_private; + unsigned long flags; + bool pending; + + if (atomic_read(&dev_priv->mm.wedged)) + return false; + + spin_lock_irqsave(&dev->event_lock, flags); + pending = to_intel_crtc(crtc)->unpin_work != NULL; + spin_unlock_irqrestore(&dev->event_lock, flags); + + return pending; +} + static void intel_crtc_wait_for_pending_flips(struct drm_crtc *crtc) { struct drm_device *dev = crtc->dev; + struct drm_i915_private *dev_priv = dev->dev_private; if (crtc->fb == NULL) return; + wait_event(dev_priv->pending_flip_queue, + !intel_crtc_has_pending_flip(crtc)); + mutex_lock(&dev->struct_mutex); intel_finish_fb(crtc->fb); mutex_unlock(&dev->struct_mutex); @@ -6149,9 +6170,8 @@ static void do_intel_finish_page_flip(st atomic_clear_mask(1 << intel_crtc->plane, &obj->pending_flip.counter); - if (atomic_read(&obj->pending_flip) == 0) - wake_up(&dev_priv->pending_flip_queue); + wake_up(&dev_priv->pending_flip_queue); schedule_work(&work->work); trace_i915_flip_complete(intel_crtc->plane, work->pending_flip_obj); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/

