purpose of /chosen node (was RE: [PATCH] powerpc: delete boot-cpu and chosen nodes from all DTSfiles)

[Benjamin Herrenschmidt]

On Fri, 2007-02-16 at 08:30 +0100, Segher Boessenkool wrote:
> > If the kernel needs a convenient place to keep a phandle to the
> > top level interrupt controller,
> 
> Well that's the first point: the kernel doesn't need this
> at all, it can derive this from the rest of the tree easy
> enough.

Not that easy. I beleive it's better to have it expressed explicitely.

> > how about just under root?
> 
> CHRP does this (in an extra-plus nasty way).
> 
> > (Or, we could make up a new node)
> 
> Duplicate node?  No way.  You can be flexible with adding
> extra properties, but every node should represent a (pseudo-)
> device, and every device in the system should be represented
> by exactly one node.
> 
> Or you could make the convention that /aliases/interrupt-controller
> points to the root interrupt controller, if you really
> think you want this.

That too.

Ben.