[Intel-gfx] drm/i915: Delay with fbc enabled

[Jani Nikula]

On Fri, 24 Jun 2016, Manuel Groß <mgr at nordkrater.de> wrote:
> since upgrading to Kernel 4.6, I experienced weird display delay issues
> on my Thinkpad x250. Downgrading to 4.5 or disabling fbc both fix that
> issue.

If that's Haswell, FBC has been disabled by default (again, *sigh*). The
fix is now in Linus' tree, and will eventually trickle down to v4.6
stable kernels.

> If you can tell me what logs/analysis might be useful for you, I am
> happy to provide it to you, although I am not that experienced with
> this stuff.

It's possible we have a real fix in drm-intel-nightly branch of [1]
already, please try that with i915.enable_fbc=1.

BR,
Jani.

[1] http://cgit.freedesktop.org/drm-intel

-- 
Jani Nikula, Intel Open Source Technology Center