[Intel-gfx] [PATCH] drm/i915: don't call swsci_setup on resume

[Chris Wilson]

On Thu, Feb 06, 2014 at 01:19:48PM -0200, Paulo Zanoni wrote:
> From: Paulo Zanoni <paulo.r.zanoni at intel.com>
> 
> This function is used to discover which swsci callbacks the machine
> supports. It calls swsci() 3 times, and usually takes a considerable
> number of milliseconds to finish.
> 
> I don't see a reason for a change on the supported callbacks between
> boot and resume, so use the values retrieved at boot time forever,
> making resume a little bit faster.

This looks unsafe following a hibernate resume where the system could
change around us. Across a suspend resume, you can argue that we do not
need to shootdown OpRegion (and not just swsci) at all.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre