Re: [RFC PATCH v2 4/6] PM: opp: allow control of multiple clocks

Viresh Kumar
2022-05-31T10:31:05Z

On 19-05-22, 10:03, Krzysztof Kozlowski wrote:
> Yes, true. The clock frequencies are still changed with each gear, but
> in general the UFS indeed operates on gear concept.

Hi Krzysztof,

I have redesigned the OPP core a bit (two patchsets until now) to make
it easier to add multiple clock support going forward. I need some
inputs from you before moving forward with it now. Will this work for
your use case:

- Add support for multiple clocks, where none of them is primary.

- Which means you won't be able to use dev_pm_opp_set_rate() but will
need something like dev_pm_opp_set_level(), will add it.

- That is, your OPP table will need to implement levels (I think of
them as UFS gears) and then call dev_pm_opp_set_level() instead.

- This new API will work just like dev_pm_opp_set_rate(), except that
it will find the target OPP based on level instead of freq and
support configuration of multiple clock frequencies.

- Of course both these APIs will share most of the code.

--
viresh