[PATCH 05/20] bootwrapper: flatdevtree fixes

Scott Wood scottwood at freescale.com
Fri Aug 24 03:48:30 EST 2007


David Gibson wrote:
> Actually, no - sorry, that's the other problem with this, which I
> forgot to mention.  On real OF, the "name" property contains the
> node's name *without the unit address*; that is, only the portion
> before the '@'.  So your getprop change does not match real OF
> behaviour - and real OF behaviour will not do what you want for
> dt_get_path().

Ah, OK.

> Actually, in any case, I don't think we want to implement get_path()
> this way for real OF.  Better to have get_path() itself as a callback:
> on real OF I believe we can directly ask for the full path to a given
> phandle, the get name based implementation can then be made specific
> to the flat device tree.
> 
> Or actually, I think we might be able to come up with a get_path()
> implementation for flat tree that's less hideous than repeatedly
> calling get_parent() which is an ugly, ugly operation on the flat tree

It's likely to be ugly no matter what, though I'll try to come up with 
something slightly nicer.  If I were doing this code from scratch, I'd 
probably liven the tree first and reflatten it to pass to the kernel.

> (and will get worse with libfdt).

Why is that?

>>Plus, something might come along that needs to dynamically look for
>>either name or something else.  It's more flexible this way.
> 
> Hrm... "something might come along" just seems contrived to me.

Well, I generally prefer doing things the more flexible way in the 
absence of a good reason not to.  OF returning the bare name is a good 
reason not to.

-Scott



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