Hello! This gist contains a Python script for extracting and inserting default enviroments from/to a PineNote Uboot image. Hopefully this works but I provide no guarantees. Maybe give it a read-over before running it, don't run code from the internet without knowing what it does, etc...
It also contains a patch for adding a boot "menu" selector based on the contents of a file. It will read mmc0:11:/boot/which_os.txt
and based on the first character in that file, boot either Android or Linux. In case of an error, it should fallback to Android.
Currently, the details for booting Linux are hard-coded in there to boot from mmc0:11
, and it's expecting an extlinux config file in /extlinux/extlinux.conf
or /boot/extlinux/extlinux.conf
.
Hope this is useful!