public inbox for intel-gfx@lists.freedesktop.org
 help / color / mirror / Atom feed
From: Imre Deak <imre.deak@intel.com>
To: Jani Nikula <jani.nikula@intel.com>, intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH 2/2] drm/i915/lspcon: Add workaround for resuming in PCON mode
Date: Fri, 21 Oct 2016 12:07:20 +0300	[thread overview]
Message-ID: <1477040840.28355.12.camel@intel.com> (raw)
In-Reply-To: <87vawmozjt.fsf@intel.com>

On pe, 2016-10-21 at 11:51 +0300, Jani Nikula wrote:
> On Fri, 21 Oct 2016, Imre Deak <imre.deak@intel.com> wrote:
> > I tried this now on the fi-skl-6700hq machine in the bug report and it
> > seems to be the same failure mode as the APL one. There is one
> > difference in that on the SKL machine once the firmware is in the stuck
> > state after suspend/resume, a warm reboot may not recover it, so during
> > the next boot the LSPCON probe will fail. I guess that during warm
> > reboot LSPCON may continue to be powered, so to fully reset it a power
> > cycle is needed. In any case this patch fixes resume on that machine
> > too, so I couldn't reproduce the problem with it even across multiple
> > reboots, whereas without it it's 100% reproducible.
> 
> A quick thought, when we do module unload or suspend, perhaps we should
> put the LSPCON to the state in which we expect to find it on
> probe/resume? In case it doesn't get reset.

The probe and resume functions handle both PCON and LS modes, switching
only if necessary. But in any case I tried the followings without
success:
- switch to LS mode during suspend
- power down the TMDS output during suspend after switching to LS mode
(DP_DUAL_MODE_TMDS_OEN) and then back on during resume
- while in PCON mode force DP_SET_POWER(D3) during suspend and then
DP_SET_POWER(D0) during resume

--Imre
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

  reply	other threads:[~2016-10-21  9:07 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-20 17:06 [PATCH 1/2] drm/i915/dp: Print full branch/sink descriptor for all outputs Imre Deak
2016-10-20 17:06 ` [PATCH 2/2] drm/i915/lspcon: Add workaround for resuming in PCON mode Imre Deak
2016-10-20 18:20   ` Jani Nikula
2016-10-20 19:20     ` Imre Deak
2016-10-20 21:07       ` Jani Nikula
2016-10-21  5:46       ` Sharma, Shashank
2016-10-21  7:40         ` Imre Deak
2016-10-20 19:24     ` Jani Nikula
2016-10-20 19:43       ` Imre Deak
2016-10-20 20:50         ` Jani Nikula
2016-10-20 21:40           ` Imre Deak
2016-10-21  7:20             ` Imre Deak
2016-10-21  8:51               ` Jani Nikula
2016-10-21  9:07                 ` Imre Deak [this message]
2016-10-20 17:47 ` ✓ Fi.CI.BAT: success for series starting with [1/2] drm/i915/dp: Print full branch/sink descriptor for all outputs Patchwork
2016-10-20 18:06 ` [PATCH 1/2] " Jani Nikula
2016-10-20 18:58   ` Imre Deak
2016-10-24  8:36   ` Daniel Vetter

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1477040840.28355.12.camel@intel.com \
    --to=imre.deak@intel.com \
    --cc=intel-gfx@lists.freedesktop.org \
    --cc=jani.nikula@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox