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Date: Mon, 10 Dec 2007 17:19:02 -0600
From: Scott Wood <scottwood@freescale.com>
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Subject: Re: [PATCH 2/3] Use embedded libfdt in the bootwrapper
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David Gibson wrote:
> On Mon, Dec 10, 2007 at 11:32:17AM -0600, Scott Wood wrote:
>> How does using offsets as devps work if a devp was previously
>> acquired to a node that has to be moved due to a change later made
>> in an earlier part of the tree?
> 
> It doesn't; don't do that.  I just don't think truly persistent 
> phandles are worth the code complexity to implement them.

We already have working code to implement them.  This is a regression 
over flatdevicetree.c, and it (or something else in libfdt) seems to be 
breaking the ep8248e wrapper (it didn't make it in to the last window 
because of dependency on a netdev patch, but I'll probably send it out 
tomorrow).

It breaks the extremely common and useful usage of:

devp = create node;
setprop(devp, "foo", something);
setprop(devp, "bar", something);

> Especially since their use more-or-less completely precludes libfdt's
> "stateless" approach, which has significant other advantages.

It doesn't preclude stateless read-only -- what are the benefits to 
stateless read-write that are worth invalidating all node references any 
time something changes?

-Scott