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Date: Thu, 8 Mar 2007 07:20:56 -0800 (PST)
From: Ben Warren <bwarren@qstreams.com>
Subject: Re: RE : Reset cause API
To: alayrac <christophe.alayrac@cresitt.com>, galak@kernel.crashing.org,
	linuxppc-embedded@ozlabs.org
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Thanks Chris & Kumar,
--- alayrac <christophe.alayrac@cresitt.com> wrote:


> The type of reset is recorded in the most-recent
> reset field of the
> debug-status register (DBSR[MRR]). System software
> can examine this
> field if it needs to determine the cause of a reset.
> The effect of a
> reset on the processor is always the same regardless
> of the type.
> 
> For more details you can see ppc-ref-guide.pdf (in
> EDK doc directory).
> Chris

The Freescale SoCs also have a Reset Status Register
(RSR) than contains the same kind of information.  I
wa s curious whether a system call exists or whether I
need to write my own.

What I'm really interested in knowing is whether the
last boot was cold(hard) or warm(soft).  The type of
products I work on have devices that must only be
initialized on a cold boot, to avoid affecting the
data path.

regards,
Ben