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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: Discussion on SOC device tree bindings
Date: Fri, 19 Jan 2007 17:50:32 +0100
To: "Yoder Stuart-B08248" <stuart.yoder@freescale.com>
Cc: linuxppc-dev Development <linuxppc-dev@ozlabs.org>,
	Sven Luther <sven@genesi-usa.com>
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> How about linking in _both_ directions?
>
> -The SOC node describes the shared register with links to the
>  the device nodes it is associated with

This provides all the information you need.

> -The device nodes link to the SOC parent shared register node
> (_but_ don't necessarily specify the device index, since that
>  could be determined by looking at the SOC node)

This information, if handy for the kernel to have, can
be trivially constructed at initialisation time by the
kernel itself.

> Doing both provides flexibility in the way the device tree
> is used.

That flexibility is already there if you describe
everything in the controller node.

> The SOC node in a single place describes the
> shared register which conceptually makes sense.

Exactly.


Segher