This question or a variant of it seems to be asked frequently enough, so apologies.
I would like the Beaglebone AI to boot from eMMC even though an SD card is present – the SD card purely a data card; that is, neither /uEnv.txt file nor /boot directory present on the disk.
One respondent suggested hacking the uboot source code, but I don’t know what that would mean, especially since /boot/uboot/ is empty in my image. (Linux beaglebone 4.14.108-ti-r131 #1buster SMP PREEMPT Tue Mar 24 19:18:36 UTC 2020 armv7l GNU/Linux)
It isn’t that big a deal at present as nothing prevents me from inserting the card after the BBAI has booted; it would just be a convenience.