Re: [PATCH 0/2] additional sysfs entries for CPPC

["Prakash, Prashanth" <pprakash@codeaurora.org>]

Hi Rafael,

On 2/13/2017 9:38 AM, Prakash, Prashanth wrote:
[...]
>>> Tested-by: Al Stone <ahs3@redhat.com>
>> I'm not actually sure about the assumption this series is based on.
>>
>> I don't see anything in the spec to guarantee that it will always be
>> safe to evaluate _CPC only once and cache its output.
> Among the Performance capabilities registers(section 8.4.7.1.1), the only
> register that can change dynamically is Guaranteed performance register.
> We are not supporting/using Guaranteed performance at the moment.
>
> Guaranteed performance Register has an associated Notify event which will be
> invoked when it changes. No such events are associated with other capabilities
> register. Similar distinction is made in the beginning of section 8.4.7.1.1:
> "Figure 8-47 outlines the static performance thresholds of the platform
>  and the dynamic guaranteed performance threshold."
>
> I agree spec isn't very clear about marking these registers as static except
> that one sentence I quoted above, but there is enough in spec to guarantee
> that the capabilities we are using will not change dynamically.

Does the above sound reasonable? Any other feedback on this patch set?

--
Thanks,
Prashanth