On Mon, Oct 04, 2021 at 09:28:43AM +0200, Rasmus Villemoes wrote:
On 02/10/2021 02.38, Simon Glass wrote:
At present U-Boot environment variables, and thus scripts, are defined by CONFIG_EXTRA_ENV_SETTINGS. It is painful to add large amounts of text to this file and dealing with quoting and newlines is harder than it should be. It would be better if we could just type the script into a text file and have it included by U-Boot.
Indeed, the pain of CONFIG_EXTRA_ENV_SETTINGS was part of the motivation for introducing CONFIG_USE_DEFAULT_ENV_FILE.
Add a feature that brings in a .env file associated with the board config, if present. To use it, create a file in a board/<vendor>/env directory called <board>.env (or common.env if you want the same environment for all boards).
The environment variables should be of the form "var=value". Values can extend to multiple lines. See the README under 'Environment Variables:' for more information and an example.
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Perhaps some remarks on how this compares/relates to CONFIG_USE_DEFAULT_ENV_FILE and CONFIG_ENV_IMPORT_FDT would be in order? In particular, the latter seems like it could already do the "amend the environent per vendor/board" with appropriate settings in the -u-boot.dtsi files?
I don't think either of those currently support using CONFIG_ variables in the definitions, but perhaps that could be fixed.
I don't have anything against these patches as such, I'd just like to understand precisely what they bring that cannot already be done with existing mechanisms.
So, the high level requirement is to move the environment out of the board.h file (or the nest of #includes that uses to cobble it together). That does mean that CONFIG_USE_DEFAULT_ENV_FILE at least would likely need some tweaking, but may also be just not as useful, if it's no longer such a pain to modify the default environment.