[BISECTED REGRESSION in 3.19-rc1] [drm/i915] WARNING: drivers/gpu/drm/drm_irq.c:1077 drm_wait_one_vblank

[Jani Nikula]

On Mon, 23 Feb 2015, Andrey Skvortsov <andrej.skvortzov at gmail.com> wrote:
> On Mon, Feb 23, 2015 at 02:54:47PM +0200, Jani Nikula wrote:
>> On Mon, 23 Feb 2015, Jani Nikula <jani.nikula at linux.intel.com> wrote:
>> > On Mon, 16 Feb 2015, Paul Bolle <pebolle at tiscali.nl> wrote:
>> >> I still see this on v3.19. I booted with drm.debug=0x4. The almost 2K
>> >> lines in dmesg containing either "[drm" or this WARNING are pasted
>> >> below. I really know nothing about all this, but I do note that only the
>> >> WARNINGS are preceded by:
>> >>     [drm:intel_calculate_wm] FIFO watermark level: -5
>> >>     [drm:i9xx_update_wm] FIFO watermarks - A: 26, B: 8
>> >>
>> >> But perhaps that's another symptom of the same issue. A bit of staring
>> >> at the code couldn't help me determine that.
>> >>
>> >> Perhaps these debug messages help someone in discovering what might be
>> >> going on here.
>> >
>> > Please try v4.0-rc1 or try cherry-picking this on top of v3.19 and
>> > report back:
>> >
>> > commit f9b61ff6bce9a44555324b29e593fdffc9a115bc
>> > Author: Daniel Vetter <daniel.vetter at ffwll.ch>
>> > Date:   Wed Jan 7 13:54:39 2015 +0100
>> >
>> >     drm/i915: Push vblank enable/disable past encoder->enable/disable
>> 
>> https://bugs.freedesktop.org/show_bug.cgi?id=89108
>> 
>
> Hi, Sitsofe,
>
> you wrote in your bug report (#89108), that you've got a black screen, when you tried drm-intel-nightly branch.
> Do you have black screen with v4.0-rc1 on your eeepc?
> If so, is it similar to that I described here https://lkml.org/lkml/2015/2/3/594 ? 
> As we both had drm_wait_one_vblank warnings, I assume that we have the same or similar chipsets.
> And your black screen could be potentially the same as mine. 

Please try https://patchwork.kernel.org/patch/5861631/

BR,
Jani.


>
> -- 
> Best regards,
> Andrey Skvortsov
>
> PGP Key ID: 0x57A3AEAD

-- 
Jani Nikula, Intel Open Source Technology Center