[PATCHv4 4/8] ARM: OMAP3: add manual control for mpu / core pwrdm usecounting

Kevin Hilman khilman at deeprootsystems.com
Fri Sep 7 17:48:29 EDT 2012


Tero Kristo <t-kristo at ti.com> writes:

> On Mon, 2012-08-06 at 12:14 +0200, Jean Pihet wrote:
>> Hi Tero,
>> 
>> On Mon, Jul 30, 2012 at 10:40 AM, Tero Kristo <t-kristo at ti.com> wrote:
>> > On Fri, 2012-07-27 at 12:36 -0700, Kevin Hilman wrote:
>> >> Tero Kristo <t-kristo at ti.com> writes:
>> >>
>> >> > mpu / core powerdomain usecounts are now statically increased
>> >> > by 1 during MPU activity. This allows the domains to reflect
>> >> > actual usage, and will allow the usecount to reach 0 just before
>> >> > all CPUs are ready to idle. Proper powerdomain usecounts are
>> >> > propageted to voltagedomain level also, and will allow vc
>> >> > callbacks to be triggered at right point of time.
>> >> >
>> >> > Signed-off-by: Tero Kristo <t-kristo at ti.com>
>> >> > Cc: Paul Walmsley <paul at pwsan.com>
>> >> > Cc: Kevin Hilman <khilman at ti.com>
>> >>
>> >> IMO, the idea is fine, but I'm not crazy about the implementation in
>> >> powerdomain.c, which is meant for pwrdm generic code.   In particular,
>> >> I'm not crazy about the pwrdm lookups in powerdomain.c.
>> >>
>> >> Since pm<soc>.c already has references to mpu_pwrdm and core_pwrdm, why
>> >> not just add the pwrdm_clkdm_enable/disable calls directly in pm<soc>.c
>> >
>> > I think this was how the patch was in some earlier rev but I thought I'd
>> > try to be more clever with this. :) I can revert the implementation back
>> > to this.
>> Furthermore after the changes in pre/post transitions [1], some more
>> checks will be needed to identify the transitions on the mpu and core
>> power domains.
>> 
>> [1] http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=e055548953355b6e69c56f9e54388845b29b4e97
>> 
>> Regards,
>> Jean
>
> Hi Kevin,
>
> What is the latest status regarding this one, seeing the patch mentioned
> got reverted due to problems? Should I do some changes for this or not?

No, using latest minline should be fine.

> I can look at moving the code away from the generic powerdomain.c at
> least, but is there anything else?

Nothing else I can think of (but my vacation has purged my brain of most
of the details here, so I may be forgetting something.)

Kevin



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