[v6 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER.

[Arjan van de Ven]

On Thu, 24 Sep 2009 10:42:41 +0530
Arun R Bharadwaj <arun at linux.vnet.ibm.com> wrote:

> * Arun R Bharadwaj <arun at linux.vnet.ibm.com> [2009-09-22 16:55:27]:
> 
> Hi Len, (or other acpi folks),
> 
> I had a question regarding ACPI-cpuidle interaction in the current
> implementation.
> 
> Currently, every cpu (i.e. acpi_processor) registers to cpuidle as
> a cpuidle_device. So every cpu has to go through the process of
> setting up the idle states and then registering as a cpuidle device.
> 
> What exactly is the reason behind this?
> 

technically a BIOS can opt to give you C states via ACPI on some cpus,
but not on others.

in practice when this happens it tends to be a bug.. but it's
technically a valid configuration



-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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