[PATCH] ARM: local timers: Allow boot CPU to have its timer running early

Rob Herring robherring2 at gmail.com
Thu Jun 2 15:38:23 EDT 2011

On 06/02/2011 11:56 AM, Marc Zyngier wrote:
> On Thu, 2011-06-02 at 18:31 +0200, Jean-Christophe PLAGNIOL-VILLARD
> wrote:
>> On 15:03 Wed 01 Jun     , Marc Zyngier wrote:
>>> Currently, the boot CPU has its local timer enabled long after
>>> the delay loop has been calibrated. This makes it impossible to
>>> boot a system that only uses local timers, like the A15.
>>> Use late_time_init hook to initialize the boot CPU local timer.
>>> Since shmobile is already using this hook, add an ARM specific
>>> arm_late_time_init hook that platforms can use instead.
>>> Cc: Paul Mundt<lethal at linux-sh.org>
>>> Cc: Magnus Damm<magnus.damm at gmail.com>
>>> Signed-off-by: Marc Zyngier<marc.zyngier at arm.com>
>> I propose to switch to early platform devce and earlytimer
>> this will avoid the arm_late_time_init hook
>> and will make it cross arch
> I believe this is orthogonal. shmobile (the only ARM user of
> late_time_init) is already doing some early_platform stuff for its
> timers.
> What I'm trying to achieve here is to make sure the timer on CPU0 is
> actually up, running and registered as a clock_event_device before we
> hit the delay loop.
> Or maybe I've misunderstood what you're pointing me to?

I believe he is referring to this patch which generically enables the 
shmobile code for ARM:


I don't think it has been pulled into mainline yet.


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