Comment 16 for bug 1797881

(In reply to Karol Herbst from comment #4)
> this is actually an issue on the 4.18.8 and newer.
>
> Those commits need to be applied to 4.18 to fix this regression:
>
> 9ebd8202393dde9d3678c9ec162c1aa63ba17eac

commit 9ebd8202393dde9d3678c9ec162c1aa63ba17eac
Author: Dhinakaran Pandiyan <email address hidden>
Date: Thu Sep 27 13:57:30 2018 -0700

    drm/i915/dp: Fix link retraining comment in intel_dp_long_pulse()

> f24f6eb95807bca0dbd8dc5b2f3a4099000f4472

commit f24f6eb95807bca0dbd8dc5b2f3a4099000f4472
Author: Dhinakaran Pandiyan <email address hidden>
Date: Thu Sep 27 13:57:31 2018 -0700

    drm/i915/dp: Restrict link retrain workaround to external monitors

> regression was caused by
>
> 399334708b4f07b107094e5db4a390f0f25d2d4f

commit 399334708b4f07b107094e5db4a390f0f25d2d4f
Author: Jan-Marek Glogowski <email address hidden>
Date: Sat Aug 25 15:10:35 2018 -0400

    drm/i915: Re-apply "Perform link quality check, unconditionally during long pulse"