Re: [Intel-gfx] [v4.6-10530-g28165ec7a99b] i915: *ERROR* "CPU pipe/PCH transcoder" A FIFO underrun

From: Sedat Dilek
Date: Mon May 30 2016 - 17:07:15 EST


On 5/28/16, Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
> On 5/27/16, Chris Bainbridge <chris.bainbridge@xxxxxxxxx> wrote:
>> On 25 May 2016 at 08:31, Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
>>> Hi Daniel,
>>>
>>> with latest Linus Git I see this with my Intel SandyBridge GPU...
>>>
>>> [ 17.629014] [drm:intel_cpu_fifo_underrun_irq_handler [i915]]
>>> *ERROR* CPU pipe A FIFO underrun
>>> [ 17.630652] [drm:intel_set_pch_fifo_underrun_reporting [i915]]
>>> *ERROR* uncleared pch fifo underrun on pch transcoder A
>>> [ 17.630685] [drm:intel_pch_fifo_underrun_irq_handler [i915]]
>>> *ERROR* PCH transcoder A FIFO underrun
>>
>> Guessing this is https://bugs.freedesktop.org/show_bug.cgi?id=95736
>>
>
> I did some last testing (for this weekend) with drm-intel-nightly
> (2016y-05m-27d-12h-32m-45s UTC) on top of Linux v4.6 final.
>
> This did not help as I see the same *ERROR* outputs.
>

With drm-intel-nightly (2016y-05m-30d-17h-51m-33s-UTC) the outputs
look a bit different and more helpful?

[ 19.139790] [drm:intel_cpu_fifo_underrun_irq_handler [i915]]
*ERROR* CPU pipe A FIFO underrun
[ 19.140274] [drm:intel_set_pch_fifo_underrun_reporting [i915]]
*ERROR* uncleared pch fifo underrun on pch transcoder A
[ 19.140299] [drm:intel_pch_fifo_underrun_irq_handler [i915]]
*ERROR* PCH transcoder A FIFO underrun

- Sedat -