Subject: [PATCH] ARM: OMAP4: PM: Avoid expensive cpu_suspend() path for all CPU power states except off

From: [email-masked] (Santosh Shilimkar)
Date: Tue, 12 Feb 2013 10:25:09 +0530

On Saturday 09 February 2013 02:49 AM, Kevin Hilman wrote:
> Santosh Shilimkar <[email-masked]> writes:
>
>> Current CPU PM code code make use of common cpu_suspend() path for all the
>> CPU power states which is not optimal. In fact cpu_suspend() path is needed
>> only when we put CPU power domain to off state where the CPU context is lost.
>>
>> Update the code accordingly so that the expensive cpu_suspend() path
>> can be avoided for the shallow CPU power states like CPU PD INA/CSWR.
>>
>> Cc: Kevin Hilman <[email-masked]>
>>
>> Reported-by: Richard Woodruff <[email-masked]>
>> Signed-off-by: Santosh Shilimkar <[email-masked]>
>
> Looks OK at first glance, but are you sure this is right for the
> various ways both clusters might idle using coupled CPUidle?
>
Yes it is perfectly safe from all C-states. This patch has been part of
the OMAP4/OMAP5 product port for some time. I forgot to send it upstream
some how :(

> Some description of the testing would be helpful here.
>
Sorry. Should have mentioned it in first place.
Patch is being tested on OMAP4430 (idle/suspend) and OMAP5 with
few out of tree patches.

Regards,
Santosh