[PATCH V4 4/5] soc: qcom: Introduce SCMI based Memlat (Memory Latency) governor

[MyungJoo Ham]

>
>Hey Dmitry,
>
>Thanks for taking time to review the series.
>
>+ Devfreq maintainers to comment (I thought you already added
>them by name)
>
>
>Hey MyungJoo/Kyungmin/Chanwoo,
>
>Can you weigh in here? Does it make sense to add a new
>class of devfreq devices that don't have governors
>associated with them just for them to export a few
>essential data to userspace? In this scenario the
>scaling algorithm is in a SCP and we just start
>them from the kernel. We do have ways to get the
>current frequency of various buses but does this
>warrant adding a new class of governor less devices?
>
>-Sibi

If voltage/frequency is controlled by SCP
(it's an SoC's internal hardware IP, right?),
it's good to have a userspace governer
with the driver not accepting updates from userspace.

E.g., Let "target" callback not update the frequency value,
 or let "target" callback always return an error with
 a dev_err message that you don't accept frequency changes
 from userspace.

Cheers,
MyungJoo.