05-04-2022, 03:53 AM
I think you're running into the 'opinionated' part of their project description - in making it simple for the most common use case they've removed some of the capabilities needed for less common use cases. According to the variants page only the SPI version (used by the PinePhone Pro but not the PinePhone) is capable of saving the environment changes that I think would be needed to change the boot order.
https://github.com/Tow-Boot/Tow-Boot/blo...ariants.md
I may have missed something that could go in /boot/extlinux/extlinux.conf (generated by u-boot-update so don't edit directly) to make it use the other boot device, but if you're going to use this way in the long term then changing the boot order in the source and compiling your own tow-boot version is probably worth the initial effort. If not then stick with u-boot or p-boot which are more configurable.
https://github.com/Tow-Boot/Tow-Boot/blo...ariants.md
I may have missed something that could go in /boot/extlinux/extlinux.conf (generated by u-boot-update so don't edit directly) to make it use the other boot device, but if you're going to use this way in the long term then changing the boot order in the source and compiling your own tow-boot version is probably worth the initial effort. If not then stick with u-boot or p-boot which are more configurable.