Have you done the process of building u-boot in arm-sdk or did you build it separately?

The 2 boards were delivered with a preinstalled OS on the eMMC memory.

I did not build/install any U-Boot code on the uSD card.

The BBB boot process is quite complex. The boot code inside the processor ROM tries first to load a SPL from the eMMC. If not found, it searches on the uSD, then UART0 then USB0, in that order. When found and loaded, the SPL loads a third stage boot loader from the same device the SPL was loaded from. It is possible to change the order by powering up the board while pressing the S2 button. The order in which the SPL is then searched: SPIO, uSD, USB0, UART0.

On the eMMC of my rev.C board, the SPL is a U-Boot SPL and the third stage boot loader is also U-Boot. Normally, based on the documentation, one expects U-Boot to load the kernel also from the eMMC. The only possibility to boot from the uSD would be to press the S2 button or erasing the eMMC. However it looks like the U-Boot on the eMMC is configured to load the uEnv.txt file from the uSD card when one is inserted. When none inserted, it loads the kernel from the eMMC.

So the image currently created by arm-sdk will work as long as the pre-loaded eMMC has not been altered/erased by the user.

I don't use any initrd for booting the devuan image.

Okay. Thanks for the info. I've merged your patches and will try a build soon :)

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