Re: [RFC PATCH 19/77] dtc: Introduce export symbols
Herve Codina <[email protected]> Fri, 16 Jan 2026 17:27:35 +0100
| Newsgroups | org.kernel.vger.devicetree-spec,org.kernel.vger.devicetree-compiler,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel |
|---|---|
| Organization | Bootlin |
| Message-ID | <[email protected]> |
Hi David, On Thu, 15 Jan 2026 16:52:26 +1100 David Gibson <[email protected]> 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