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

From: Sudeep Holla
Date: Wed May 31 2017 - 13:34:12 EST




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
--
Regards,
Sudeep