[Intel-gfx] [RFT 2/2] drm/i915/icl: Switch to using 12 deep CSB status FIFO

[Chris Wilson]

Quoting Chris Wilson (2019-04-05 21:46:57)
> From: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> 
> Now when we can support variable csb fifo sizes, disable legacy mode.
> By disabling legacy we hope to get better hw testing coverage by
> assuming everyone else have switched over.

There should be no advantage here until we transition to a larger
submission queue -- but just maybe this helps with say
https://bugs.freedesktop.org/show_bug.cgi?id=110338
-Chris