U-Boot Concept Tree Proposal

[Neil Armstrong]

Hi Simon,

On 6/3/26 07:06, Simon Glass wrote:
> Dear U-Boot Contributors,
> 
> I would like to introduce the U-Boot Concept tree along with a few thoughts
> on its role in U-Boot.
> 
> By way of background, I have been a contributor for about 15 years - around
> 10k commits and countless reviews. I have introduced many innovations into
> the project: e.g. sandbox, device tree, C test infrastructure, Binman,
> standard boot. Of course I could not have done any of this without the
> U-Boot community (nor would there be any point).
> 
> As the U-Boot project has matured, the demands for mainline stability and
> rigorous review have created a natural friction for landing complex,
> large-scale feature and refactoring series at the necessary pace. This
> structural reality, which has slowed the adoption of ambitious efforts like
> bootstd, VBE, xPL [1], and CI-connected hardware labs, is what the Concept
> tree is designed to alleviate.

The main issue to land complex large-scale feature and refactoring series is
mainly the lack of human highly qualified reviewers, proper shared project
infrastructure and funding for paid work. Not developers.

> 
> I strongly believe that projects must evolve in order to stay relevant in
> the long term. This includes code-refactoring, new features and subsystems,
> along with migration of old code to use them.  A look back at the U-Boot of
> 2010 shows how far the project has come. I don't think anyone would still
> be using U-Boot if it had not evolved.
> 
> I have set up a 'Concept' tree, a possible future for U-Boot, as a way to
> regain the old pace of innovation. This environment is a proving ground for
> new features where we maintain a lower bar for risk tolerance and
> completeness. We will accept partial and speculative features, provided the
> underlying code remains robust and of high quality, with the shared
> understanding that features may be dropped if they do not prove beneficial.

I'm clearly against having a separate official "U-Boot" fork tree, this will
only lead to confusion to users and contributors if it shares the same
mailing-list and name.

> 
> Another difference is AI. I believe that AI is the next step on from
> compilers, which also took a long time to produce good code and find
> acceptance. The Concept tree welcomes (and encourages) high-quality AI
> contributions and reviews. It accepts PRs and allows reviews on PRs or the
> mailing list. It relies 99% on automated tests (sandbox, QEMU and labs) so
> sets a high bar for testing. It uses a separate Gitlab instance for now and
> of course uses a separate mailing list and Patchwork project to avoid
> cluttering the main list. Concept runs an AI-powered cherry-picker so that
> it keeps up with mainline. In no sense is it operated as a fork.

I'm clearly against using AI for any of development or review work as it
can't be fully trusted and will monopolize precious reviewers time reviewing
AI code instead of reviewing legitimate contributions from individual and companies.

Using AI for CI testing and regression testing could help if it doesn't add
a burden for maintainers by reporting false positives.

> 
> Once features are landed and functional in Concept I hope that many will
> find their way to mainline, although inevitably some rework will be needed.

Still I don't understand your point, Linux or Zephyr can land very complex
features with a single tree, what make U-Boot different here ?

> 
> I recognise that introducing a new 'Concept' tree might initially cause
> confusion or concern. This is an invitation to work together to define its
> role. I welcome all feedback - positive or negative - here on the mailing
> list, privately, or on irc. Let’s discuss how this initiative can help
> U-Boot remain the defining firmware for the 2030s.

Our immediate priority is helping U-Boot establish the proper technical and
legal infrastructure to receive funding. Adding AI features, maintaining
separate forks, and managing competing domains only distracts us from the
critical task of switching off the dying Denx infrastructure.

This is my personal opinion,
Neil

> 
> [1]
> https://lore.kernel.org/u-boot/CAFLszTg6sKpZ1yP3Pjgk9_Fx3MOh=ieT2oaHfgLf3_nC+xXA9g@mail.gmail.com/
> 
> Concept tree:
>                         :
>                         ::
>                       ...:::.
>                   ::  :. -
>             .   ::::::-  - ::. ..
>            .:: .:      -==  =.:.
>          ::.- ::::. ::. :=:. ::::
>    ::. ::   =..  :.-::: =:
>      .:-:-. -.::  ::=-:=:
>    ::::::=.  -.::   ===:       ::.
>      ::.:::=::=:   -===:--==-::--::
>        :.    :-=-.:==:.   .:  ::
>                 ===:       ::  :
>                 ==:
>                 ==
>                :==
>                -==:
>                -+=:
>                =++=.
>               .-===: