[Intel-gfx] [PATCH v4 25/26] drm/i915: Add sysfs interface to know the HW requested frequency

[Kamble, Sagar A]

On 9/9/2016 10:13 PM, Chris Wilson wrote:
> On Fri, Sep 09, 2016 at 06:21:44PM +0530, Sagar Arun Kamble wrote:
>> With SLPC, user can read this value to know SLPC requested frequency.
> Not SLPC specific, even elsewhere there may be a delay between the cur
> value and the req (just means something more on SLPC).
cur_freq is updated whenever RPNSWREQ is written so they should be same 
right?
Where will delay come into picture?
>
> Though I'm never keen on expanding the stable ABI, I can't object to
> this given the existence of the others - but I will ask for a use case
> other than debug.
For testing SLPC requests from Host side we have to rely on read of RPNSWREQ
> -Chris
>