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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Geoff Levand <geoffrey.levand@am.sony.com>
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Date: Tue, 24 May 2005 09:53:35 +1000
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Cc: linuxppc-dev@ozlabs.org
Subject: Re: [PATCH] add machine state register support
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On Mon, 2005-05-23 at 16:40 -0700, Geoff Levand wrote:
> This patch adds routines to get and set the machine state register.  These 
> are needed by power management code on some platforms.
> 
> Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com> for CELF

Hi Geoff !

Can you tell me more about this power management code ? I tend to think
that code that wants to do more than just using the existing accessors
should be written in assembly... 

Also, there is already

void _nmask_and_or_msr(unsigned long nmask, unsigned long or_val);

That you can use for manipulating MSR bits.

Finally, I tend to prefer such small register accessors to be written as
inline assembly in some headers. But then, I don't think you actually
need to add anything here.

Regards,
Ben.