Re: [PATCH v4 0/4] Introduce fdtgrep for subsetting and hashing FDTs

[Simon Glass <sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>]

+Rob Herring

Hi David and Rob,

On Tue, 8 Feb 2022 at 23:31, David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org> wrote:
>
> On Tue, Feb 08, 2022 at 02:43:44PM -0700, Simon Glass wrote:
> > Hi David,
> >
> > On Sun, 6 Feb 2022 at 21:10, David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org> wrote:
> > >
> > > On Sun, Nov 07, 2021 at 03:43:42PM -0700, Simon Glass wrote:
> > > > Note: This was last sent 6 years ago. It really belongs upstream and I
> > > > believe it is useful functionality for libfdt, so I am trying again.
> > > > Please take a fresh look at this. It is cut back from the previous series.
> > > > If accepted we can expand the feature set piece by piece from here.
> > >
> > > Sorry it's taken me so long to look at this.  Again.  I can't dispute
> > > that it's useful for certain use cases.  But as for belonging
> > > upstream...
> > >
> > > This series adds quite a lot of conceptual complexity.  It introduces
> > > a new data structure, new state structures, a entirely new mode of
> > > working with a tree and a bunch of configuration parameter types on
> > > top of the new entry points and new tool.  I still find the semantics
> > > of the different criteria for inclusion/exclusion from a region pretty
> > > bewildering.
> >
> > It is sufficient to achieve its purpose, but I don't think it is any
> > more complex than that.
>
> I don't disagree, but that still ends up being quite complex.
>
> > > That makes me pretty disinclined to add this to the scope of
> > > maintenance for libfdt.  As you've probably noticed, I'm already
> > > struggling to keep on top of maintenance for the existing libfdt
> > > interfaces.  AFAICT everything here can be implemented fairly
> > > naturally in terms of libfdt's existing public interface. so I'm not
> > > really seeing a compelling reason for this to be merged into libfdt,
> > > rather than being its own separate library that depends on libfdt.
> >
> > Are you suggesting:
> >
> > 1. that libfdt should move to a new maintainer
> > 2. that you would accept these patches if someone else maintained them
> > within the libfdt tree
> > 3. that we set up a separate tree to fork libfdt, with these changes in
> > 4. that we put these changes in a separate tree?
>
> Right now (4) is what I'm suggesting.  Or to be more precise, creating
> a new repo with "libfdtrange" or whatever, that depends on libfdt.
>
> (1) and/or (2) are potentially worthy of further discussion.  (3) is
> just a bad idea, IMO.

Where are things going with device tree validation in terms of
source-code location? Is it likely there might be a separate tree for
that, which could perhaps hold other libfdt dependent things?

Regards,
Simon