I created an SD card image for the Olinuxino Lime 2 eMMC from Debian stable installer version. I used the firmware for Lime 2 eMMC and put u-boot compiled as indicated by https://wiki.debian.org/InstallingDebianOn/Allwinner#Olimex_A20-OLinuXino-LIME2__rev._F_and_newer_and_Debian11.2F_bullseye_kernel
Then, I ran the installer and chose to install on eMMC. I can boot it by putting the micro SD card in and removing it when u-boot started and before the debian installer is started from the micro SD card, then it boots fine, I can ssh to it.
However, I haven't found out how to install u-boot on the eMMC, so that I don't need to use the micro SD card. I tried the instructions at https://linux-sunxi.org/Bootable_eMMC but then it still won't boot without the micro SD card.
What is the way to copy u-boot to the eMMC so that it will boot without the micro SD card?
Look at our scripts. In our builds and images there is install script already. Here:
https://github.com/OLIMEX/olinuxino-tools/blob/master/src/scripts/olinuxino-sd-to-emmc
Maybe just test with Olimage too, you can find info about Olimage here:
https://github.com/OLIMEX/OLINUXINO/blob/master/DOCUMENTS/OLIMAGE/Olimage-guide.pdf