[RFC] consolidated libdt proposal

[Mark A. Greer]

On Tue, Aug 08, 2006 at 01:25:10PM -0500, Hollis Blanchard wrote:
> On Tue, 2006-08-08 at 11:04 -0700, Mark A. Greer wrote:
> > 
> > Except for not being able to extend a property (see below),
> > I think it does meet my needs (at least as I know them today).
> 
> Great.
> 
> > However, I was hoping to keep the interfaces in the bootwrapper
> > similar to the ones used in the kernel.  To that end, I had a
> > routine to find a device node and other routines to find and modify
> > a property within that node.  I didn't notice a "finddevice" type of
> > function to find a device node.  Would you have a problem adding one?
> 
> The way property modification works now is this:
> 	p = ft_get_prop(tree, "/xen/console/interrupts", &len);
> 	if ((NULL == p) || (len != foolen))
> 		return;
> 	*p = cpu_to_be32(foo);
> (That does need to be hidden in a yet-to-be-written ft_set_prop().)
> 
> If necessary, it looks like it would be possible to modify ft_get_prop()
> to return a pointer to the beginning of the node structure, but is it
> really necessary?

No, its just a preference to have it look similar to kernel code.

> Do you have code that would be difficult to convert to
> using
> 	ft_set_prop(tree, "/node/prop", buf, buflen);
> ?

No.

> > > One limitation of the attached code is that it doesn't support changing
> > > the *size* of properties, though I don't think that would be too
> > > difficult to add if needed.
> > 
> > If we're going to allow cmdline editing in the bootwrapper, we would
> > need to extend the size of a property.  We've never really talked about
> > cmdline editing in the powerpc branch but I assume that its a good
> > thing(tm).  I know I would like to have it so, IMHO, I think we should
> > add it (and therefore require extending a property).
> 
> I agree, and it shouldn't be too much work. I'll take a look later this
> week, if nobody else has.

OK.

Mark