U Boot - FrankBau/meta-marsboard-bsp GitHub Wiki

Das U-Boot is a versatile boot loader from http://www.denx.de/

On the MarS board, it is used to

• read the Linux kernel and device tree blob from the first (FAT) partition of the microSD card
• pass control to the Linux kernel which will continue the boot process, thereby mounting the root file system from the second partition (ext4) of the microSD card.

It can be used for much more, including low level board bring-up or updating itself.

Further reading:

• Build the U Boot boot loader
• Update U-Boot in SPI Flash