Re: [PATCH] drm/i915: boost GPU and CPU freq when leaving idle

[Arjan van de Ven <arjan@linux.intel.com>]

On 6/28/2013 11:37 AM, Chris Wilson wrote:
> On Fri, Jun 28, 2013 at 09:54:32AM -0700, Jesse Barnes wrote:
>> Coming out of idle is usually due to some sort of user input (swiping a
>> screen, clicking a button) and often results in some sort of graphical
>> animation.  To prevent stutter for a CPU or GPU intensive animation,
>> boost the GPU and CPU freq to the maximum to get the first frame out as
>> quickly as possible.  The normal CPU and GPU frequency management code
>> will take over from there and (hopefully) clock down to save power as
>> needed if the max frequencies aren't required.
>>
>> This could probably be done more cleanly, and possibly without another
>> uncached read in the execbuf path if we tracked idleness elsewhere.  I'm
>> also unsure about the cpufreq calls; I don't really know if this will do
>> what I want...
>
> Would seem like a good idea to make intel_mark_busy() dtrt and use them.
> -Chris
>

Is there a way to force the GPU always to run at the top speed?
(since it might well be the most efficient way to run things due to race-to-halt)