On 2024-01-18 16:11, Michael Walle wrote:
Using CONFIG_EXTRA_ENV_SETTINGS should be good enough to provide
the fallback defaults. However, the users can still mess the things
up,
but again, they can do that already in many places.
I disagree. In my case that is a last resort recovery. And it should
work in any case. Even if the user has messed up anything (except
from erasing the bootloader in the SPI flash ;)).
Maybe the solution could be another compile-time option to "lock down"
the built-in defaults provided through CONFIG_EXTRA_ENV_SETTINGS? If
that new option is selected, changes to the environment would make no
changes to the built-in defaults, i.e. those parts of the environment
would actually be ignored.
Not sure locking down the whole environment is a good idea.
Not the entire environment, just the default button-command associations
supplied through CONFIG_EXTRA_ENV_SETTINGS. I'm sorry if I didn't write
it clearly before.
In summary, the registered (compiled-in) command should always take
precedence. If one wants to supply a default command which can be
changed later, that can go via the (compiled-in) default
environment.
Sorry, this is a bit confusing to me. Didn't you write above that
the users should be able to change the associated commands through
the environment variables?
I had two kinds of button commands in mind: immutable ones and
mutable
ones. The first can be achieved with compiled-in commands, the second
with a default environment and environment variables.
Also, whether a command is a mutable one or not is the decision of
the developer (or the one who's compiling/configuring u-boot),
not the user.
I believe that the additional compile-time option, which I proposed
above, could be extended to specify which of the built-in default
button-command associations are immutable, and which are allowed to
be modified through the environment variables.
IIRC there is already a mechanism for that. Environment hooks
or something like that. But I'm not sure that has other implications
and qualify as simple and lightweight for this use-case.
Anyway, we digress. I just wanted to make you aware of another
use-case, which btw. is already done today in the lsxl board for
example.
