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Date: Thu, 13 Sep 2007 14:21:38 +1000
From: David Gibson <david@gibson.dropbear.id.au>
To: Kumar Gala <galak@kernel.crashing.org>
Subject: Re: [PATCH v3] [POWERPC] 85xx: Add basic Uniprocessor MPC8572 DS port
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On Wed, Sep 12, 2007 at 10:28:24PM -0500, Kumar Gala wrote:
[snip]
> >> +	soc8572@ffe00000 {
> >
> > You should put an interrupt-parent in here, so you can get rid of
> > it in all the children.
> 
> Are interrupt-parent's inherited by child nodes?

Strictly speaking, a node's default interrupt-parent is its physical
parent.  And a node without interrupt-map identity maps all interrupts
to *its* parent.  So the interrupt is notionally wired from the child
to its parent and so forth up the bus tree until it reaches a node
with a specified interrupt-parent or interrupt-map.

-- 
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