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Subject: Re: Locking in the clk API
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Colin Cross <ccross@google.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>,
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Date: Sat, 22 Jan 2011 10:21:42 +1100
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On Fri, 2011-01-21 at 14:28 -0800, Colin Cross wrote:
> Clocks that have a voltage dependency, or depend on a clock that has a
> voltage dependency, are non-atomic, everything else is atomic.  PLLs
> are atomic because they lock very fast (300 uS or 1ms) 

Some could argue that this is still way too slow for atomic context :-)

Cheers,
Ben.