[PATCH v3 02/15] dt/bindings: Update binding for PM domain idle states

Sudeep Holla sudeep.holla at arm.com
Wed Aug 10 11:13:36 PDT 2016



On 10/08/16 19:09, Sudeep Holla wrote:
>
>
> On 10/08/16 17:40, Lina Iyer wrote:
>> Hi Sudeep,
>>
>> On Wed, Aug 10 2016 at 09:15 -0600, Sudeep Holla wrote:
>>> Hi Lina,
>>>
>>> I have few concerns mainly due to the lack of description and not the
>>> binding per say.
>
> [...]
>
>>>> +- domain-idle-states : A phandle of an idle-state that shall be
>>>> soaked into a
>>>> +                generic domain power state. The idle state
>>>> definitions are
>>>> +                compatible with arm,idle-state specified in [1].
>>>> +
>>>
>>> So I assume these can be used for the genpd states. Either we rename
>>> it domain-power-states or make it clear that these domain-idle-states
>>> can also represent the power-states for normal devices.
>>>
>> These are the domains' idle states. These states are only used when the
>> domain goes into idle, not when the domain is active. These are not
>> power states that the domain can operate on either. Hence the idle-state
>> moniker.
>
> I am not sure if we can tell that the device is running in all it's
> power states. E.g. in ACPI IIUC, only D0 state represent running state,
> while D{1,2,3} are power states which consume less power than D0/running
> state. I think genpd is designed on those lines.
>

I didn't complete this section earlier.

Just to clarify we can label them as idle states or whatever. Strictly
speaking today even cpu-idle-states have power off state, so the term is
not important.

What I intended to say is that it should be able to describe even device
idle(power states minus the active running) states.

-- 
Regards,
Sudeep



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