Need to re-write U-boot from Pinephone pro currently in mass rom mode

[wibble]

Hi fxc;
I have a question though. the U-boot image is likely a bin file. is it possible to know on which language it was written ? can we legally write our own code to use instead of those official release ? if yes, how is the right way to start from your perspective ?

Best Regards

It's mostly C and GPL-2+ so you can modify if you want. I think tow-boot is a specific configuration of u-boot to make it 'Just Work' so long as distros stick to a specific pattern. Distros may be using patches that aren't yet upstreamed, so check the distro source if you want to know exactly what went into the version you used. Some distros better document their build process than others. For general u-boot docs see:

https://u-boot.readthedocs.io/en/latest/
https://www.denx.de/wiki/U-Boot/