Re: [RFC/PATCH 0/5] DVFS in the OPP core

From: Viresh Kumar
Date: Fri Feb 08 2019 - 02:17:32 EST


On 07-02-19, 14:37, Ulf Hansson wrote:
> I think we also need to consider cross SoC drivers. One SoC may have
> both clocks and OPPs to manage, while another may have only clocks.

We already have that case with CPUs as well and dev_pm_opp_set_rate()
takes care of it.

> Even it this may be fairly uncommon, we should consider it, before we
> decide to fold in additional clock management, like
> clk_prepare|unprepare() for example, behind the dev_pm_opp_set_rate()
> API.
>
> The point is, the driver may need to call clk_prepare|enable()
> anyways, unless we make that conditional depending on a DT compatible
> string, for example. Of course, because the clock prepare/enable is
> reference counted, there may not be a problem in practice to have both
> the OPP and driver to deal with it.

--
viresh