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Date:   Wed, 23 Feb 2022 11:22:28 +0000
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Subject: Re: [PATCH v2 0/2] Introduce 'advanced' Energy Model in DT
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To:     Viresh Kumar <viresh.kumar@linaro.org>,
        Daniel Lezcano <daniel.lezcano@linaro.org>
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        rafael@kernel.org, nm@ti.com, sboyd@kernel.org, mka@chromium.org,
        dianders@chromium.org, robh+dt@kernel.org,
        devicetree@vger.kernel.org, linux-pm@vger.kernel.org
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 <20220223104341.jh5hjcv6ugaexgoa@vireshk-i7>
From:   Lukasz Luba <lukasz.luba@arm.com>
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On 2/23/22 10:43, Viresh Kumar wrote:
> On 23-02-22, 10:52, Daniel Lezcano wrote:
>> why not extend the energy model to any kind of devices?
> 
> FWIW, the OPP core supports a wide range of devices now, not just CPUs.
> 

Is that the "opp-level" thing which would allow that?
I can see some DT files with regulators(?) using it e.g. [1].
It looks flexible, the opp-hz is not hard requirement,
the opp-level can be used instead IIUC.

It might be a next step which might meet Daniel's needs.
If that 'level' can be any number and frequency is not available
then EM must have 'level' filed in the struct em_perf_state
for this kind of new devices. I'm open for such change.
We can discuss this as a next step. We would need to find some examples
how this new thing would be used.

[1] 
https://elixir.bootlin.com/linux/v5.17-rc5/source/arch/arm/boot/dts/tegra20-peripherals-opp.dtsi#L4