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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [PATCH 06/17] Document the linux,network-index property.
Date: Fri, 23 Mar 2007 12:36:58 +0100
To: David Gibson <david@gibson.dropbear.id.au>
Cc: linuxppc-dev@ozlabs.org, Yoder Stuart-B08248 <stuart.yoder@freescale.com>
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[...flat device tree labels...]

> They're of no use at present if you compile direct to dtb.  They're
> potentially useful, however, if you compile to asm output, because the
> labels are transcribed into symbols within the asm.
>
> The idea is intended to be useful for systems where the bootloader has
> to do some poking of the device tree, but doesn't need to change the
> size of any properties.

Nor needs to change any device tree structure (add/remove
properties / nodes).

> In that case the bootloader can do all the
> necessary fixups on the tree without *any* understanding of the flat
> tree structure.

Well it still needs to know property encoding...

> It simply links in the device tree structure, and
> symbols within it reference all the necessary points for adjustment.

Yeah.  That would be useful if you really only need to change
the contents of a few fixed-size properties.

It would be interesting to see if anyone actually uses this
feature ;-)


Segher