[PATCH v5 2/6] ARM: smp_scu: add a helper for powering on a specific CPU

Russell King - ARM Linux linux at armlinux.org.uk
Mon Aug 14 03:52:18 PDT 2017

On Fri, Jul 28, 2017 at 11:21:34PM +0200, Martin Blumenstingl wrote:
> +/*
> + * Set the executing CPUs power mode to SCU_PM_NORMAL.
> + *
> + * This function must be called with preemption disabled, and as it
> + * has the side effect of disabling coherency, caches must have been
> + * flushed. Interrupts must also have been disabled.

This comment looks rather misleading for several reasons:

1. we're bringing another CPU to normal power mode, which means it's
   coming _into_ coherency, not leaving coherency, so "side effect of
   disabling coherency" is wrong.

2. what has the state of the _local_ CPUs caches got to do with the
   remote CPU when it isn't even powered up?

Could you please reword this comment to be more accurate please - I
think the paragraph can be removed.

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