Hi Lukas,
On 7/2/24 8:48 AM, lukas.funke-oss@weidmueller.com wrote:
From: Lukas Funke lukas.funke@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