[Intel-gfx] [PATCH 08/36] drm/i915: Reduce RPS update frequency on Valleyview/Cherryview

[Chris Wilson]

Quoting Sagar Arun Kamble (2018-03-15 09:23:25)
> 
> 
> On 3/14/2018 3:07 PM, Chris Wilson wrote:
> > Valleyview and Cherryview update the GPU frequency via the punit, which
> > is very expensive as we have to ensure the cores do not sleep during the
> > comms.
> But the patch 5 applies this workaround to only VLV.

Still using an indirect method that uses a RTT, so still true that the
punit access is noticeable.
-Chris