"uboot-install" equivelant?

What it the equivelant to “grub-install” for uboot? That is, what sectors should I copy (with dd?) from one uSD to another uSD?

I have my M64 up and running Armbian Focal from its built in uSD and I want to do two things:

  1. make a copy of the running system on the emmc (I think I need to do something to get the emmc to show up as /dev/mmcblk1) and make it bootable – this would be an “emergency” backup. I don’t want to just dd the whole uSD, since it is a 32G card and the emmc is only 8G (the uSD only has 5 or so Gig in use).

  2. make a second uSD card bootable – I have already copied (using rsync) the running system to an identically partitioned uSD card, connected via a USB uSD adapter.

If this was a PC, I would just run grub-install. Obviously that makes no sense, but I believe there is some magic in the boot sectors (between the MBR and the start of the first partition) that contains uboot and whatever data it needs to start. What is the proper way to copy that info?

There are different eMMC chips and not all are supported in upstream u-boot. You need to add eMMC driver to u-boot. Once its there, you can use normal install procedure.

normal install procedure

But what is the “normal install procedure”?