Re: [RFC PATCH v3 0/2] Add Krait Cache Scaling support

[Sibi Sankar]

On 2020-08-24 16:10, Viresh Kumar wrote:
> +Vincent/Saravana/Sibi
>
> On 21-08-20, 16:00, Ansuel Smith wrote:
> > This adds Krait Cache scaling support using the cpufreq notifier.
> > I have some doubt about where this should be actually placed (clk or 
> > cpufreq)?
> > Also the original idea was to create a dedicated cpufreq driver (like 
> > it's done in
> > the codeaurora qcom repo) by copying the cpufreq-dt driver and adding 
> > the cache
> > scaling logic but i still don't know what is better. Have a very 
> > similar driver or
> > add a dedicated driver only for the cache using the cpufreq notifier 
> > and do the
> > scale on every freq transition.
> > Thanks to everyone who will review or answer these questions.
>
> Saravana was doing something with devfreq to solve such issues if I
> wasn't mistaken.
>
> Sibi ?

IIRC the final plan was to create a devfreq device
and devfreq-cpufreq based governor to scale them, this
way one can switch to a different governor if required.
(I don't see if ^^ applies well for l2 though). In the
interim until such a solution is acked on the list we
just scale the resources directly from the cpufreq
driver. On SDM845/SC7180 SoCs, L3 is modeled as a
interconnect provider and is directly scaled from the
cpufreq-hw driver.

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