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From: robherring2@gmail.com (Rob Herring)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: local timers: Allow boot CPU to have its timer running early
Date: Thu, 02 Jun 2011 14:38:23 -0500	[thread overview]
Message-ID: <4DE7E6AF.4020404@gmail.com> (raw)
In-Reply-To: <1307033815.31098.31.camel@e102391-lin.cambridge.arm.com>

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@linux-sh.org>
>>> Cc: Magnus Damm<magnus.damm@gmail.com>
>>> Signed-off-by: Marc Zyngier<marc.zyngier@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:

http://www.spinics.net/lists/arm-kernel/msg123736.html

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

Rob

  reply	other threads:[~2011-06-02 19:38 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-01 14:03 [PATCH] ARM: local timers: Allow boot CPU to have its timer running early Marc Zyngier
2011-06-02  6:04 ` Paul Mundt
2011-06-02 16:31 ` Jean-Christophe PLAGNIOL-VILLARD
2011-06-02 16:56   ` Marc Zyngier
2011-06-02 19:38     ` Rob Herring [this message]
2011-06-03  8:20       ` Marc Zyngier
2011-06-03  8:55       ` Russell King - ARM Linux
2011-06-03 13:55         ` Rob Herring
2011-06-06  5:20         ` Magnus Damm
2011-06-03  8:57 ` Russell King - ARM Linux
2011-06-03  9:11   ` Marc Zyngier
2011-06-06  9:25   ` Paul Mundt

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