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Date:   Wed, 23 Feb 2022 11:40:33 +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>
Cc:     linux-kernel@vger.kernel.org, dietmar.eggemann@arm.com,
        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
References: <20220222140746.12293-1-lukasz.luba@arm.com>
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 <94d3f2a3-4145-afdc-d810-61f2120df579@arm.com>
 <20220223112727.akprxqglyr7ostqh@vireshk-i7>
From:   Lukasz Luba <lukasz.luba@arm.com>
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On 2/23/22 11:27, Viresh Kumar wrote:
> On 23-02-22, 11:22, Lukasz Luba wrote:
>> 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.
> 
> There are many other devices which still use Freq.
> 
>> Is that the "opp-level" thing which would allow that?
> 
> For power supplies/regulators, we don't have freq and they use level, right.
> 
> Also for interconnect we use bandwidth, in a similar way.
> 
>> 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.
> 
> Right.
> 

Looks good. It also doesn't collide with this patch set.

We could have an opp entry like:

	opp_1: opp-1 {
		opp-level = <1>;
		opp-microwatt = <200000>;
	};

Daniel would that design make sense to you?


If yes, we could discuss this further after this first
step for fixing GPU in merged. I would need to re-think
the EM em_perf_state and maybe the new ::level there.