[PATCH 0/4] bloblist: fdt: Clean up the code

[Raymond Mao]

Hi Simon,

On Thu, 3 Apr 2025 at 13:57, Simon Glass <sjg at chromium.org> wrote:
>
> Hi Raymond,
>
> On Fri, 4 Apr 2025 at 03:09, Raymond Mao <raymond.mao at linaro.org> wrote:
> >
> > Hi Simon,
> >
> > On Fri, 28 Mar 2025 at 11:44, Simon Glass <sjg at chromium.org> wrote:
> > >
> > > The bloblist code took what I consider to be a wrong turn a year or so
> > > ago. As discussed with Tom, this series proposes a way to arrange things
> > > so that it is simpler to understand and manage.
> > >
> > > - Unwind some of the nesting in bloblist_init()
> > > - Avoid needing to init the bloblist just to get the FDT
> > > - Create a deterministic OF_BLOBLIST option rather than using guesswork
> > >
> > We now have a kconfig BLOBLIST_PASSAGE_MANDATORY which means
> > mandatorily use bloblist to hand over everything between boot stages
> > including fdt, creating OF_BLOBLIST is not necessary.
>
> Yes, I noticed that, but BLOBLIST_PASSAGE_MANDATORY indicates that
> there must be a bloblist, not that it must contain a devicetree. So I
> wasn't sure about removing it.
>

See my comments to your [2/4] patch, if BLOBLIST_PASSAGE_MANDATORY is
selected, we can override any fdt from board or env with the one from
the bloblist.
Moreover, it is not just for fdt, but for everything that is being
handed over from the previous boot stage using bloblist, but
OF_BLOBLIST is for fdt only.
I don't think it is a good idea to replace BLOBLIST_PASSAGE_MANDATORY
with OF_BLOBLIST.

Regards,
Raymond

> But actually, thinking about it just now, we can remove
> BLOBLIST_PASSAGE_MANDATORY, since U-Boot won't make it that far if
> there is no bloblist. It will die in fdtdec_setup(). Take a look and
> see if you agree.
>
> >
> > > It is to be hoped that we can get a platform which uses OF_BLOBLIST into
> > > CI at some point. In the meantime, the standard passage series[1] could
> > > be resurrected to give some coverage.
> > >
> > > [1] https://patchwork.ozlabs.org/project/uboot/list/?series=281465&state=*
> > >
> > >
> > > Simon Glass (4):
> > >   bloblist: Simplify bloblist init
> > >   fdt: Introduce OF_BLOBLIST
> > >   bloblist: Provide access to the FDT address
> > >   fdt: Obtain the FDT from bloblist without parsing it
> > >
> > >  arch/arm/lib/xferlist.c            |   6 +-
> > >  common/bloblist.c                  | 102 ++++++++++++++++++-----------
> > >  doc/develop/devicetree/control.rst |   3 +
> > >  dts/Kconfig                        |   8 +++
> > >  include/bloblist.h                 |  16 ++++-
> > >  lib/fdtdec.c                       |  65 +++++++-----------
> > >  6 files changed, 116 insertions(+), 84 deletions(-)
> > >
> > > --
> > > 2.43.0
> > >
>
> Regards,
> Simon