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Date: Thu, 23 Apr 2009 12:59:56 -0500
From: Scott Wood <scottwood@freescale.com>
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Cc: Linuxppc-dev Development <linuxppc-dev@ozlabs.org>,
	Timur Tabi <timur@freescale.com>
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Anton Vorontsov wrote:
> This is exactly what we should try to avoid. We should not accept
> any changes that might break older firmwares. That is, keep the
> device tree workable with X1 and X2, by any means.

I think that's a much bigger restriction than trying to keep the kernel 
compatible with older device trees.  Consider changes in the physical 
memory map, etc.

> If X1 looks for "/soc8323@..."  and X2 looks for "/soc@...", so that
> Z1 and Z2 aren't compatible at all, then we're in trouble. But we're
> in trouble regardless of what Linux is doing, no?

Not if Linux can continue to deal with X1 and Z1.

-Scott