[Intel-gfx] [PATCH 2/2] drm/i915: Simplify ilk-ivb underrun suppression

[Chris Wilson]

Quoting Ville Syrjala (2018-05-24 20:04:06)
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Let's suppress the underruns around every modeset sequence instead
> of trying to avoid it. Planes are disabled at this point anyway so
> we don't really gain anything from keeping the underrun reporting
> enabled. Also for PCH ports we already suppress all underruns here
> anyway so trying avoid it for the CPU eDP doesn't seem all that
> important.
> 
> Maybe this gets rid of some lingering spurious underruns?

I'll bite. Isn't the reason for enabling underrung report for the
modeset itself to detect errors in our sequence?

How certain are we that these are hw limitations vs sw bugs?
-Chris