On Tue, 19 May 2015, Mario Kleiner <mario.kleiner.de@xxxxxxxxx> wrote: > On 05/15/2015 11:00 AM, Jani Nikula wrote: >> On Fri, 15 May 2015, Mario Kleiner <mario.kleiner.de@xxxxxxxxx> wrote: >>> Hi all, >>> >>> since Linux 4.0 i experience some massive display flicker problem on my >>> Intel HD Ironlake mobile (2010 MacBookPro6,2) under Waylands reference >>> compositor Weston. >>> >>> - Only happens on Linux >= 4.0 on intel-kms with the Intel HD, not under >>> nouveau-kms with the discrete NVidia gpu. Strangely on Linux 4.1-rc it >>> happens all the time, whereas on Linux 4.0 it can work normally for >>> quite a while, but once the problem starts only a reboot can cure it. >>> >>> - Almost only happens on Weston, but only very rarely under the XServer. >>> VT switching from Weston to XOrg makes the problem disappear, switching >>> back to Weston and it starts again immediately. >>> >>> - Only happens if a hardware cursor is displayed - hiding the cursor >>> stops the flicker immediately, showing the cursor starts the flicker. >>> >>> - The drm and desktop is completely idle during this - drm.debug=15 >>> shows no activity while this happens. >>> >>> Symptom: >>> >>> Up to the scanline where the cursor is located, the desktop image is >>> displayed, but jumps horizontally left and right by some random number >>> of pixels, maybe in the range 0 - 200 pixels with high frequency, making >>> the content unreadable. Starting with the scanline where scanout of the >>> cursor starts, the display goes blank, as if some display controller >>> fifo would underflow and the controller blanks the display in response. >>> Seems having to scanout the cursor plane in addition to the primary >>> plane is just enough to push it over some limit? >>> >>> I also see cpu and pch pipe a fifo underruns reported by the underflow >>> irq handlers. >>> >>> I saw there were many changes around Linux 4.0 in the kms driver wrt. >>> watermark calculations, so this might be related? >> >> Please try http://patchwork.freedesktop.org/patch/49314 and report back. >> >> BR, >> Jani. >> > > The patch fixes my flicker problem nicely. Thanks! If you want, you can > add a > > Tested-by: Mario Kleiner <mario.kleiner.de@xxxxxxxxx> Thanks for testing, I've pushed the fix to drm-intel-fixes, headed to -rc5. BR, Jani. > > best, > -mario -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
