Re: [PATCH] ARM: cpuidle: Support asymmetric idle definition

From	Daniel Lezcano <daniel.lezcano@linaro.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH] ARM: cpuidle: Support asymmetric idle definition
Date	2017-06-01 09:40 +0200
Message-ID	<tNsS6-81U-3@gated-at.bofh.it> (permalink)
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On 31/05/2017 19:33, Sudeep Holla wrote:
> 
> 
> On 31/05/17 17:40, Daniel Lezcano wrote:
> 
>> Hi Sudeep, Lorenzo,
>>
>> I have been thinking and looking at the domain-idle-state and I don't
>> see an obvious connection between what is describing the power domain,
>> the cpu idle driver and what we are trying to achieve.
>>
> 
> I am not sure what you mean by *connection* above.
> 
> 1. With old flat list of idle states, we should get the cpumask sharing
>    the idle states from the phandle or something similar.
> 2. With new domain-idle-state and hierarchical DT binding, you just need
>    to infer that from the hierarchy.
> 
>> I would like to suggest something much more simple, register a cpuidle
>> driver per cpu, so every cpu can have its own idle definitions, that
>> should work for dynamiQ, smp and hmp. The impact on the driver will be
>> minimal.
>>
> 
> Sounds simple, but not sure if it's scalable on platforms with
> relatively large number of CPUs like 48 or 96(e.g. Cavium Thunder

I'm pretty sure it scales, we had the idle states per cpuidle devices
and nobody was complaining. But I agree it could be optimized.


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Re: [PATCH] ARM: cpuidle: Support asymmetric idle definition Daniel Lezcano <daniel.lezcano@linaro.org> - 2017-05-31 18:50 +0200
  Re: [PATCH] ARM: cpuidle: Support asymmetric idle definition Sudeep Holla <sudeep.holla@arm.com> - 2017-05-31 19:40 +0200
    Re: [PATCH] ARM: cpuidle: Support asymmetric idle definition Daniel Lezcano <daniel.lezcano@linaro.org> - 2017-06-01 09:40 +0200

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