diff options
| author | Rasmus Villemoes <rasmus.villemoes@prevas.dk> | 2021-04-21 11:06:54 +0200 |
|---|---|---|
| committer | Tom Rini <trini@konsulko.com> | 2021-05-04 11:50:50 -0400 |
| commit | 95fd9772011f29fad2c40fbc3060b5dac042152c (patch) | |
| tree | e06d8d10b7e5cd0b011372786ae918067b982d3e /env/Kconfig | |
| parent | 1cbfed8d3e9254d7e2a9466498ef867f7cb3f4cd (diff) | |
env: allow environment to be amended from control dtb
It can be useful to use the same U-Boot binary for multiple purposes,
say the normal one, one for developers that allow breaking into the
U-Boot shell, and one for use during bootstrapping which runs a
special-purpose bootcmd. Or one can have several board variants that
can share almost all boot logic, but just needs a few tweaks in the
variables used by the boot script.
To that end, allow the control dtb to contain a /config/enviroment
node (or whatever one puts in fdt_env_path variable), whose
property/value pairs are used to update the run-time environment after
it has been loaded from its persistent location.
The indirection via fdt_env_path is for maximum flexibility - for
example, should the user wish (or board logic dictate) that the values
in the DTB should no longer be applied, one simply needs to delete the
fdt_env_path variable; that can even be done automatically by
including a
fdt_env_path = "";
property in the DTB node.
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Diffstat (limited to 'env/Kconfig')
| -rw-r--r-- | env/Kconfig | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/env/Kconfig b/env/Kconfig index 1b7906cf72..1411f9e815 100644 --- a/env/Kconfig +++ b/env/Kconfig @@ -670,6 +670,24 @@ config DELAY_ENVIRONMENT later by U-Boot code. With CONFIG_OF_CONTROL this is instead controlled by the value of /config/load-environment. +config ENV_IMPORT_FDT + bool "Amend environment by FDT properties" + depends on OF_CONTROL + help + If selected, after the environment has been loaded from its + persistent location, the "env_fdt_path" variable is looked + up and used as a path to a node in the control DTB. The + property/value pairs in that node is then used to update the + run-time environment. This can be useful to use the same + U-Boot binary with different board variants. + +config ENV_FDT_PATH + string "Default value for env_fdt_path variable" + depends on ENV_IMPORT_FDT + default "/config/environment" + help + The initial value of the env_fdt_path variable. + config ENV_APPEND bool "Always append the environment with new data" default n |