[PATCH v3 1/3] ARM: add cpufreq transiton notifier to adjust loops_per_jiffy for smp

Shawn Guo shawn.guo at linaro.org
Sun Sep 9 21:17:45 EDT 2012

On Fri, Sep 07, 2012 at 10:55:00AM -0600, Stephen Warren wrote:
> Yes, that does solve the problem (well, with s/late_init/late_initcall/).
> As you imply, that change wouldn't help if cpu-tegra.c was built as a
> module.

I doubt that.  Have you confirmed it with testing?  When you install
module cpu-tegra, the pcie initialization has been done, right?

> So, is this something you can work around in your patch?
Before we head to a solution, we need to identify the cause.

One thing I note is there is no loops_per_jiffy updating in cpu-tegra
driver.  But if I understand correctly, the driver is running on
MP system.  It should update loops_per_jiffy when cpu frequency
changes, right?  I'm worrying about that the timeout in tegra pcie
driver just happens to work with a wrong loops_per_jiffy, but becomes
broken when loops_per_jiffy gets correct.


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