On 12/06/2019 10.43, Stefano Babic wrote:
Hi Pascal,
On 12/06/19 10:20, Linder Pascal wrote:
Hi everyone,
I am currently moving the configurations of the KM boards from header files to Kconfig. But for the customly defined environment variables I did not found a decent solution until I have come across the default environment file, which seems very interesting to me.
To this day, nevertheless, it appears that noone made use of the CONFIG_USE_DEFAULT_ENV_FILE configuration defined in env/Kconfig. Does anyone still have an example for this kind of environment definition or knows how to create it?
In my opinion, this could be highly relevant for the transition away from the header files in include/configs.
Fully agree. Rather, I do not think there is a relevant example. But the environment is something like data and should not be part of the header file as it is for histoical reason. I added some times ago a way to extract the environment from the header and make the transition easy (see make u-boot-initial-env). And if the environment is split from the header as CONFIG_USE_DEFAULT_ENV_FILE allows, it is also easier to set an own environment via OE BSP layer without pushing for each small change to U-Boot. Not only, environments often conflict, and what is good for a project becomes evil for another one.
Yup. FWIW, here's a small snippet from our Yocto recipe that creates the default env file:
ENV_INPUT = "common.txt board.txt" ENV_INPUT_append_basic-test = " testctrl.txt"
python do_configure() { import fileinput with open("uboot.txt", "w") as out: for line in fileinput.input(files=d.getVar("ENV_INPUT").split()): line = d.expand(line) # Strip backslash-newline if line.endswith("\\n"): line = line[:-2] out.write(line) }
The line = d.expand(line) allows us to use ${SOME_BITBAKE_VARIABLE} in the input files and have them replaced appropriately - this can be quite useful to e.g. configure a tftp server address differently.
Rasmus