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Subject: Re: [PATCH] powermac: support G5 CPU hotplug
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Johannes Berg <johannes@sipsolutions.net>
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Date: Thu, 03 May 2007 08:03:49 +1000
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On Wed, 2007-05-02 at 16:33 +0200, Johannes Berg wrote:
> On Wed, 2007-05-02 at 20:55 +1000, Paul Mackerras wrote:
> 
> > Ultimately we want to put the disabled cpus in sleep mode, but that
> > will require a suitable cache flush routine.
> 
> I don't have any docs for the particular processors the G5s have, do
> they have a sleep mode?

They have, but the cache flush is not trivial to do (and might imply
access to non documented bits). So let's put that on the to-do list and
stick to NAP for now while I dig something.

Ben.