From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Fri, 21 Jan 2011 23:21:42 +0000
Subject: Re: Locking in the clk API
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To: linux-arm-kernel@lists.infradead.org

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.