[PATCHv3 1/7] ARM: mvebu: ensure CPU clocks are enabled

Jason Cooper jason at lakedaemon.net
Wed Jul 16 06:02:51 PDT 2014


On Wed, Jul 09, 2014 at 05:45:09PM +0200, Thomas Petazzoni wrote:
> In the Armada XP SMP support code, we are reading the clock frequency
> of the booting CPU, and use that to assign the same frequency to the
> other CPUs, and we do this while the clocks are disabled.
> 
> However, the CPU clocks are in fact never prepared/enabled, and to
> support cpufreq, we now have two code paths to change the frequency of
> the CPU clocks in the CPU clock driver: one when the clock is enabled
> (dynamic frequency scaling), one when the clock is disabled (adjusting
> the CPU frequency before starting the CPU). In order for this to work,
> the CPU clocks now have to be prepared and enabled after the initial
> synchronization of the clock frequencies is done, so that all future
> rate changes of the CPU clocks will trigger a dynamic frequency
> scaling transition.
> 
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
> ---
>  arch/arm/mach-mvebu/platsmp.c | 1 +
>  1 file changed, 1 insertion(+)

Tentatively applied patches 1-3, and 5 to mvebu/soc-cpufreq to get some
coverage in -next.

thx,

Jason.



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