Re: [RFC PATCH 19/77] dtc: Introduce export symbols
From: Herve Codina
Date: Fri Jan 16 2026 - 11:27:41 EST
Hi David,
On Thu, 15 Jan 2026 16:52:26 +1100
David Gibson <david@xxxxxxxxxxxxxxxxxxxxx> wrote:
> On Mon, Jan 12, 2026 at 03:19:09PM +0100, Herve Codina wrote:
> > Export symbols allow to define a list of symbols exported at a given
> > node level. Those exported symbols can be used by an addon when the
> > addon is applied on the node exporting the symbols.
>
> This seems to imply an addon always applies at a single node location.
> I'm not sure that's a good design choice, since I don't see how it
> covers the case of something that connects to several connectors.
Apply the addon on a node that knows about those connectors.
>
> > In order to perform
> > its symbol resolution. Any unresolved phandle value will be resolved
> > using those exported symbols.
> >
> > The feature is similar to __symbols__ involved with overlay but while
> > all symbols are visible with __symbols__, only specific symbols
> > (exported symbols) are visible with export symbols.
>
> This paragraph doesn't make sense to me. What's a "symbol" if it's
> not something in __symbols__ or export symbols?
An imported symbols ?
/import/ foo "blabla";
from the addon point of view where this /import/ is present, 'foo' is a
symbol.
>
> > Also an exported symbol has a specific name and this name has to
> > used for symbol resolution. Having this specific name allows to:
> >
> > - Have several nodes providing the same exported symbols
> > name but each of them pointing to different nodes.
>
> That's not a property of having a specific name, that's a property of
> being local to a node.
Yes, exactly. I will reword.
Best regards,
Hervé