[Intel-gfx] Skylake graphics regression: projector failure with 4.8-rc3

[Jani Nikula]

On Mon, 19 Sep 2016, James Bottomley <James.Bottomley at HansenPartnership.com> wrote:
> On Mon, 2016-09-19 at 08:09 -0700, James Bottomley wrote:
>> On Sun, 2016-09-18 at 13:35 +0200, Thorsten Leemhuis wrote:
>> > Hi! James & Paulo: What's the current status of this?
>> 
>> No, the only interaction has been the suggestion below for a revert,
>> which didn't fix the problem.
>> 
>> >  Was this issue discussed elsewhere or even fixed in between? Just 
>> > asking, because this issue is on the list of regressions for 4.8.
>> 
>> 
>> I'm just about to try out -rc7, but it's not fixed so far.
>
> OK, with -rc7 and the i915 fixes, there seems to be a marked
> improvement.  I can no longer crash the crtc by using lots of xrandr
> switches, which was the principal problem.
>
> I've so far only got one of these in the logs
>
> [14858.635035] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR*
> CPU pipe B FIFO underrun
>
> And the only residual problem seems to be that the monitor goes blank
> periodically, but this can be fixed by switching resolution a couple of
> times.
>
> I haven't seen any of the link training errors so far and I've run
> through my usual battery of be nasty to the external monitor tests.

Thanks for the update. We still have fixes for the underruns in the
pipeline.

BR,
Jani.


-- 
Jani Nikula, Intel Open Source Technology Center