env: CONFIG_DEFAULT_ENV_FILE and CFG_EXTRA_ENV_SETTINGS

[Tony Dinh]

On Fri, Jul 12, 2024 at 9:50 AM Tom Rini <trini at konsulko.com> wrote:
>
> On Fri, Jul 12, 2024 at 10:14:27AM +0200, Rasmus Villemoes wrote:
> > Tony Dinh <mibodhi at gmail.com> writes:
> >
> > > Hi Tom,
> > >
> > > I'm trying to move some envs from a board header file to the default
> > > env file. I recall that the envs in CONFIG_DEFAULT_ENV_FILE are
> > > appended to the envs in CFG_EXTRA_ENV_SETTINGS. As you mentioned here
> > > before:
> > >
> > > https://lore.kernel.org/all/20220810170439.GJ1146598@bill-the-cat/
> > >
> > > But it looks like envs in CFG_EXTRA_ENV_SETTINGS are completely
> > > erased, and then the envs are populated with what's in
> > > CONFIG_DEFAULT_ENV_FILE.
> > >
> >
> > Author of CONFIG_DEFAULT_ENV_FILE here.
> >
> > Yes, the point of that option is that you supply the entire and full
> > intended default environment in that file. No U-Boot CONFIG_ options of
> > CFG_* defines or anything else affects what goes into the default env
> > when that option is used. [At run-time, U-Boot probably injects/sets a
> > few env vars, but that's true regardless of how the default env came to
> > be].
> >
> > I think there may be some confusion with the much newer
> > CONFIG_ENV_SOURCE_FILE, which is another mechanism entirely. In that
> > case the pointed-to source file is sent through cpp, thus allowing some
> > u-boot config stuff to be used/referenced, and I think some further
> > bells-and-whistles also exist. I don't know if CFG_EXTRA_ENV_SETTINGS
> > are taken into account in that case or not.
>
> Yes, I think you're right about the confusion as I too missed that in my
> reply.

OK, thank you all for your clarification!

All the best,
Tony


>
> --
> Tom