From: Oliver Neukum <oliver@neukum.org>
To: linux-pm@lists.linux-foundation.org
Subject: Re: [linux-pm] pm loss development
Date: Sat, 14 May 2011 20:53:34 +0200
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Cc: "Rafael J. Wysocki" <rjw@sisk.pl>,
        Raffaele Recalcati <lamiaposta71@gmail.com>,
        davinci-linux-open-source@linux.davincidsp.com,
        linux-kernel@vger.kernel.org
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Am Donnerstag, 12. Mai 2011, 21:27:44 schrieb Rafael J. Wysocki:
> On Thursday, May 12, 2011, Raffaele Recalcati wrote:
> > What happen normally in runtime pm implementation is that every devices
> > are switched off and are enabled only when needed.
> > In our case instead we have a completely functional embedded system and,
> > when an asyncrhonous event appear, we have only some tens milliseconds
> > before the actual power failure takes place.
> > This patchset add a support in order to switch off not vital part of the system,
> > in order to allow the board to survive longer.
> > This allow the possibility to save important data.
> 
> OK, so first, who decides what parts of the system are vital and what aren't?

If you know that power is failing in a few miliseconds, only stuff that can lead to data
corruption is vital. In that timeframe you can't even flush buffers.

	Regards
		Oliver
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