[Intel-gfx] external screen goes black

Jonathan Adamczewski jonathan.adamczewski at gmail.com
Thu Jan 24 21:16:53 CET 2013


Any further thoughts on this issue?


On Sun, Jan 20, 2013 at 1:17 PM, Jonathan Adamczewski <
jonathan.adamczewski at gmail.com> wrote:

> Yanking and re-plugging the DP cable did work when I tried it. My
> recollection is that there have been times when it hasn't worked, though
> it's possible there was something else going on (user error, etc...)
>
> Regarding the "hotplug interrupt for DP" message: that /does not/ fire
> when the screen goes black. It did fire when yanking the cable, and again
> when re-plugging.
>
> fwiw, when the screen goes blank, it does not appear to drop to a low
> power or no-sync state: the power light remains solid (if I disable the
> monitor with xrandr etc, the power light will pulse). Sometimes the picture
> will return with no intervention required and there is no apparent delay
> while the monitor "resyncs", it's instant off, instant on. The screen can
> go black for periods <1 second. If video is still playing, it's likely to
> go black a second time and to not return.
>
> Many thanks for you help so far - what's my next course of action?
>
> j.
>
>
>
> On Sun, Jan 20, 2013 at 3:52 AM, Daniel Vetter <daniel at ffwll.ch> wrote:
>
>> Hm, it's a DP screen which I've suspected (those are the kind who can
>> lose sync and go black). But somehow we don't get any hotplug event
>> when this happens - so the driver has no idea that the link went bad
>> and that we need to retrain. Can you please test this with this
>> snippet:
>>
>> diff --git a/drivers/gpu/drm/i915/intel_dp.c
>> b/drivers/gpu/drm/i915/intel_dp.c
>> index 1492706..5e91242 100644
>> --- a/drivers/gpu/drm/i915/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/intel_dp.c
>> @@ -2580,6 +2580,8 @@ intel_dp_hot_plug(struct intel_encoder
>> *intel_encoder)
>>  {
>>         struct intel_dp *intel_dp = enc_to_intel_dp(&intel_encoder->base);
>>
>> +       printk("hotplug interrupt for DP\n");
>> +
>>         intel_dp_check_link_status(intel_dp);
>>  }
>>
>> Also please check whether yanking and re-plugging the DP cable will
>> restore the display - it should.
>> -Daniel
>>
>> On Sun, Jan 20, 2013 at 5:45 AM, Jonathan Adamczewski
>> <jonathan.adamczewski at gmail.com> wrote:
>> > Thanks for the reply, Daniel.
>> >
>> > Full traces are attached. I booted the system, ran dmesg after logging
>> in
>> > through kdm.
>> >
>> > (Then I left the system while doing some other errands, hence the gap in
>> > time)
>> >
>> > I then started firefox, went to youtube and started watching some 4K
>> > resolution videos. The external screen went black in less than a minute.
>> > Second file is dmesg run after that - there doesn't appear to be much to
>> > see...
>> >
>> > There was nothing in dmesg that correlated directly with the screen
>> going
>> > black. I've validated this by triggering the screen going black several
>> > times (that's not in the attached log, though) - there was never
>> anything in
>> > dmesg that happened at the same time or that happened for tens of
>> seconds
>> > thereafter.
>> >
>> >
>> > What's the next step for gathering information here?
>> >
>> > Many thanks
>> >
>> > Jonathan.
>> >
>> >
>> >
>> >
>> >
>> > On Sat, Jan 19, 2013 at 5:39 PM, Daniel Vetter <daniel at ffwll.ch> wrote:
>> >>
>> >> Hi Jonathan,
>> >>
>> >> Can you please boot with drm.debug=0xe and then attach the complete
>> >> dmesg once right after boot, and once after the screen went black?
>> >>
>> >> Thanks, Daniel
>> >>
>> >> On Sun, Jan 20, 2013 at 1:38 AM, Jonathan Adamczewski
>> >> <jonathan.adamczewski at gmail.com> wrote:
>> >> > Hardware is a Dell XPS laptop, xorg log reports "Integrated Graphics
>> >> > Chipset: Intel(R) Sandybridge Mobile (GT2)"
>> >> >
>> >> > Running a custom configured 3.7.2 based kernel,
>> >> > xf86-video-intel-2.20.17.
>> >> >
>> >> > I'm running the internal LVDS screen at 1080p and a Dell 2713HM
>> monitor
>> >> > at
>> >> > 2560x1440 connected via display port.
>> >> >
>> >> > Both screens run fine when X starts, but at some point the external
>> >> > monitor
>> >> > will go black. The system doesn't recognize it as being disconnected
>> -
>> >> > no
>> >> > KDE popup asking if I want to change the monitor config as happens
>> when
>> >> > pulling the DP or power on the monitor.
>> >> >
>> >> > Sometimes it will return to life after a short amount of time, most
>> of
>> >> > the
>> >> > time it stays black indefinitely. A full power cycle of the monitor
>> >> > (pulling
>> >> > the plug) will usually bring it back to life, but typically not for
>> >> > long.
>> >> >
>> >> > The screen usually goes black while there's a high degree of display
>> >> > activity - a video playing, moving large windows around the screen,
>> >> > looking
>> >> > around in google streetview, etc. It doesn't seem to matter which
>> screen
>> >> > the
>> >> > activity is on.
>> >> >
>> >> > It *seems* to be less likely if I run the external display at a lower
>> >> > resolution.
>> >> >
>> >> > There's nothing that coincides with the screen going black in dmesg
>> or
>> >> > the
>> >> > xorg log.
>> >> >
>> >> > I've had no problems with this monitor under Windows 7 (gaming,
>> videos,
>> >> > etc).
>> >> >
>> >> > What I'm looking for: ideally a simple fix :) Otherwise, any
>> suggestions
>> >> > about where to look to gather more information on what could be
>> >> > happening
>> >> > here - or other places to ask for help.
>> >> >
>> >> > Many thanks
>> >> >
>> >> > jonathan.
>> >> >
>> >> > _______________________________________________
>> >> > Intel-gfx mailing list
>> >> > Intel-gfx at lists.freedesktop.org
>> >> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>> >> >
>> >>
>> >>
>> >>
>> >> --
>> >> Daniel Vetter
>> >> Software Engineer, Intel Corporation
>> >> +41 (0) 79 365 57 48 - http://blog.ffwll.ch
>> >
>> >
>>
>>
>>
>> --
>> Daniel Vetter
>> Software Engineer, Intel Corporation
>> +41 (0) 79 365 57 48 - http://blog.ffwll.ch
>>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/intel-gfx/attachments/20130124/f62c8b96/attachment.html>


More information about the Intel-gfx mailing list