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Subject: Re: [PATCH v4] drm/i915: Re-apply "Perform link quality check,
 unconditionally during long pulse"
To:     Jani Nikula <jani.nikula@linux.intel.com>,
        Lyude Paul <lyude@redhat.com>, intel-gfx@lists.freedesktop.org
Cc:     stable@vger.kernel.org,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        David Airlie <airlied@linux.ie>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
References: <20180825191035.3945-1-lyude@redhat.com>
 <871sak5hdu.fsf@intel.com>
From:   Jan-Marek Glogowski <glogow@fbihome.de>
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Date:   Mon, 27 Aug 2018 18:59:26 +0200
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Am 27.08.2018 um 10:43 schrieb Jani Nikula:
> On Sat, 25 Aug 2018, Lyude Paul <lyude@redhat.com> wrote:
>> From: Jan-Marek Glogowski <glogow@fbihome.de>
>>
>> This re-applies the workaround for "some DP sinks, [which] are a
>> little nuts" from commit 1a36147bb939 ("drm/i915: Perform link
>> quality check unconditionally during long pulse").
>> It makes the secondary AOC E2460P monitor connected via DP to an
>> acer Veriton N4640G usable again.
>>
>> This hunk was dropped in commit c85d200e8321 ("drm/i915: Move SST
>> DP link retraining into the ->post_hotplug() hook")
>>
>> Fixes: c85d200e8321 ("drm/i915: Move SST DP link retraining into the ->post_hotplug() hook")
>> [Cleaned up commit message, added stable cc]
>> Signed-off-by: Lyude Paul <lyude@redhat.com>
>> Signed-off-by: Jan-Marek Glogowski <glogow@fbihome.de>
>> Cc: stable@vger.kernel.org
>> ---
>> Resending this to update patchwork; will push in a little bit
> 
> Is there a bugzilla? Reference to a list discussion? Something with a
> dmesg where someone can actually verify this is the right fix?

The bug is at https://bugs.freedesktop.org/show_bug.cgi?id=107446
The original thread starts here:
https://lists.freedesktop.org/archives/intel-gfx/2018-August/172940.html

Jan-Marek