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Date: Wed, 9 Nov 2011 10:13:31 -0600
From: Scott Wood <scottwood@freescale.com>
To: Zhao Chenhui <chenhui.zhao@freescale.com>
Subject: Re: [PATCH 4/7] powerpc/85xx: add support to JOG feature using
 cpufreq interface
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Cc: Jerry Huang <Chang-Ming.Huang@freescale.com>, linuxppc-dev@lists.ozlabs.org
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On Wed, Nov 09, 2011 at 07:38:13PM +0800, Zhao Chenhui wrote:
> On Mon, Nov 07, 2011 at 12:50:24PM -0600, Scott Wood wrote:
> > On 11/07/2011 04:27 AM, Zhao Chenhui wrote:
> > > There is only one ppc_proc_freq. no lock.
> > 
> > I realize there's only one.
> > 
> > I'm asking whether CPUs can have their frequencies set indpendently --
> > if the answer is no, and this function is not specific to a CPU, my only
> > concern is the lock.  Either this function can be called multiple times
> > in parallel, in which case the ppc_proc_freq update should be inside the
> > lock, or it can't, in which case why do we need the lock at all?
> > 
> > -Scott
> 
> Yes. They can be changed independently.
> I will set ppc_proc_freq inside the lock.

If they can be changed independently, what does the global ppc_proc_freq
mean?

-Scott