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Date: Wed, 18 Mar 2015 12:29:43 +0530
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Subject: Re: [PATCH v2 3/4] cpufreq: mediatek: add Mediatek cpufreq driver
From: Viresh Kumar <viresh.kumar@linaro.org>
To: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
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On 12 March 2015 at 16:45, Pi-Cheng Chen <pi-cheng.chen@linaro.org> wrote:
> The voltages of the two regulators need to be always under a limitation:
> 100mV < Vsram - Vproc < 200mV
> For now, I just calculate the OPPs of Vsram from OPPs of Vproc.
>
> Another thing I should mention, if the voltage difference of two adjacent
> OPPs is greater than 100mV, we need to set the regulator to some
> voltages which are not in OPP table considering the limitation above.
> I think that will make it more difficult to model such flow in a generic
> framework.

Actually the problem is that OPP tables are insufficient for such cases,
and we are adding work-arounds to fix that. Though it will get fixed
with the new bindings we are adding.

I am confused on what we should be doing here. Even if you write
your own driver, you will be abusing DT with incorrect information.

Even if you go around adding a new driver, I would like you to fallback
to cpufreq-dt ones the new OPP bindings are in place.