Re: [PATCH 0/7] of: overlay: Add support for export-symbols node feature

[Herve Codina]

Hi David,

On Fri, 10 Jan 2025 15:26:23 +1100
David Gibson <david@xxxxxxxxxxxxxxxxxxxxx> wrote:

> On Wed, Jan 08, 2025 at 10:47:19AM +0100, Herve Codina wrote:
> > Hi Ayush,
> > 
> > On Wed, 8 Jan 2025 13:58:04 +0530
> > Ayush Singh <ayush@xxxxxxxxxxxxxxx> wrote:
> > 
> > ...  
> > > 
> > > I will experiment with adding support to dtc and see how things look. 
> > > Hopefully, 2025 is the year of addon board support.
> > >   
> > 
> > Also one point different between fdtoverlay an runtime loading is
> > that runtime loading allows to set the target node of the overlay
> > at runtime.  
> 
> I'm not really sure what you mean by "runtime loading".  Do you mean
> the kernel's implementation of loading dtbo overlays?

Yes, exactly.

> 
> While that is a different implementation from the one in fdtoverlay
> (AIUI), they're both working from the same dtb format.  As we
> discovered attempting Ayush's proposal, it turns out that the dtbo
> simply doesn't have the information we need to correctly path
> substitutions; and it's not at all easy to add it.
> 
> So, the problem of the encoding format needs to be solved regardless
> of which implementation is actually processing the overlays.
> 

What is the issue with the encoding format?

It works on my side (kernel loading) and I didn't see anything problematic.

Best regards
Hervé