Re: [PATCH 01/16] PM / OPP: Add 'supply-names' binding

From: Viresh Kumar
Date: Thu Oct 08 2015 - 05:27:46 EST


Rob,

On 15-09-15, 08:17, Viresh Kumar wrote:
> On 14-09-15, 15:22, Rob Herring wrote:
> > What if we have a 2nd device and supply rail? For example, what if the
> > L2$ has a separate rail from the cores but is linked to the OPPs.
>
> Right, so that is the case with the Mediatek SoC as well, AFAIR. How
> do we plan to treat L2 devices? For example, in the mediatek cpufreq
> driver, they change L2's supplies together with CPUs.
>
> One way to get that done, with such very closely bound devices is to
> add two regulators:
>
> cpu-supply = ...;
> l2-supply = ...;
>
> And then a property in OPP table:
>
> supply-name = "cpu", "l2";
>
> And maybe fix the order in which the supplies which be updated, based
> on the order in which entries are present in the above property.
>
> Any other way you suggest for doing that ?
>
> > Remind me of when do we have multiple regulators for a cpu?
>
> I haven't seen that yet, but its more like what I explained above.
> i.e. one for the CPU and other one for the L2 cache.
>
> But, these bindings do apply for other devices as well, where it
> should be very much possible.

Not sure if you still have any objections to this patch?

--
viresh
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