On Mon, Nov 29, 2010 at 7:31 PM, Sundar <sunder.svit@gmail.com> wrote:
Hi Vincent,

> On Mon, Nov 29, 2010 at 3:19 PM, Vincent Guittot <vincent.guittot@linaro.org> wrote:
>>
>> This patch extracts the common code of the cpu hotplug feature across
>> arm platforms. The goal is to only keep the specific stuff of the
>> platform in the sub-architecture. I have created a hotplug.c file in
>> the  arm/common directory after studying the cpu hotplug code of
>> omap2, realview, s5pv310, ux500 and tegra. I have extracted 3 main
>> platform dependent functions:
>>  -platform_enter_lowpower which prepares the platform for low power.
>>  -platform_do_lowpower on which the cpu will loop until it becomes
>> really plugged (spurious wake up). This function must returned the cpu
>> Id in order to leave the unplug state.
>>  -platform_leave_lowpower which restore the platform context.
>>  An ux500 patch is available which uses the common/hotplug.c code.
>> This patch is quite short because the idle / power down functions are
>> not yet upstreamed
>>
>

I had posted a patch which does exactly the same thing sometime ago,
but it got dropped
off from the radar. The patch set can be referenced
http://www.spinics.net/lists/arm-kernel/msg97600.html
I remember getting it Acked by most of the platform maintainers, but
Russell had some
reservations on that.

It is unfortunate that we didn't catch that work when we started on this. Let us continue discussion on the other sub-thread of the current posting.

/Amit