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Date: Fri, 4 Jan 2008 10:35:09 +1100
From: David Gibson <david@gibson.dropbear.id.au>
To: Jochen Friedrich <jochen@scram.de>
Subject: Re: [PATCHv3] powerpc: DBox2 Board Support
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Cc: Scott Wood <scottwood@freescale.com>, linuxppc-dev@ozlabs.org,
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On Thu, Jan 03, 2008 at 12:46:23PM +0100, Jochen Friedrich wrote:
> Hi David,
> 
> >> +/ {
> >> +	model = "unknown,dbox2"; // boot wrapper fills in correct manufacturer
> > 
> > Probably better just to leave model out of the dts and let the
> > bootwrapper add it.
> 
> Unfortunately, dtc requires a model:
> 
> $ dtc arch/powerpc/boot/dts/dbox2.dts
> DTC: dts->dts  on file "arch/powerpc/boot/dts/dbox2.dts"
> ERROR: Missing "model" property in /

Ah.  That should be gone in newer dtc versions.  I'm pretty sure I got
rid of all checks that enforced the presence of particular properties,
precisely because they give frequent spurious errors when things are
supposed to be filled in by the bootloader.

[snip]
> >> +				label = "Flash without bootloader";
> >> +				reg = <20000 7e0000>;
> >> +			};
> >> +			ovpartition@0 {
> >> +				label = "Complete Flash";
> >> +				reg = <0 800000>;
> >> +				read-only;
> >> +			};
> >> +		};
> >> +	};
> 
> MTD handles this correctly. dbox2 uses "Flash without bootloader"
> for flashing image updates and "Complete Flash" for creating a
> backup of everything.  OpenWRT also uses overlapping partitions BTW
> (and also for flashing updates).

Heh.  Wow.  Safely?  i.e. if you access one partition then later an
overlapping partition, is mtd guaranteed to get the necessary
synchronization right?

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson