[PATCH 0/2] Import environment variables from FIT configuration

[Quentin Schulz]

Hi Lukas,

On 7/2/24 8:48 AM, lukas.funke-oss at weidmueller.com wrote:
> From: Lukas Funke <lukas.funke at weidmueller.com>
> 
> 
> This series enables U-Boot to import environment variables from the
> selectd FIT configuration. One use-case is that the overall build process
> enriches the FIT configuration node with dm-verity information which
> should be injected into the kernel commandline. U-Boot will then read
> these (possibly signed) environment variables and put them into the
> actual Kernel commandline using variable replacement
> (see CONFIG_BOOTARGS_SUBST).
> 
> Example:
> 
> Config:
> CONFIG_BOOTARGS_SUBST=y
> CONFIG_ENV_IMPORT_FIT_CONF=y
> 
> FIT:
>      configurations {
>          default = "conf-1";
>              conf-1 {
>                  kernel = "kernel-1";
>                  fdt = "fdt-1";
>                  env,dm-verity-args = "dm-mod.create=...";
>                  env,bar = "someothervalue";
>              };
>      };
> 
> U-Boot cmdline:
> => env set bootargs="rootfstype=squashfs root=/dev/xyz ${dm-verity-args} ro"
> => boot
> 
> Kernel cmdline:
> Kernel command line: rootfstype=squashfs ... dm-mod.create= ...
> 
> 

I think FIT supports storing U-Boot scripts and running those via 
`source` command (usually the file extension is .scr).

I do not know if there's support for automatically loading this .scr as 
part of a config node though, but if there isn't I guess it'd make more 
sense to support this case than to come up with yet another implementation?

What do you think?

Cheers,
Quentin