Use U-Boot

• Device Firmware Upgrade (DFU)
• Environment Variables
• Device Tree Overlays
• Flat Image Tree (FIT)
• Network console
• Partitions
• Command-line Parsing

Shell commands

• addrmap command
• askenv command
• base command
• bootefi command
• booti command
• bootmenu command
• button command
• cbsysinfo
• conitrace command
• echo command
• exception command
• U-Boot extension board usage (CONFIG_EXTENSION)
• exit command
• false command
• fatinfo command
• for command
• load command
• loady command
• mbr command
• md command
• mmc command
• pinmux command
• pstore command
• qfw command
• reset command
• sbi command
• sf command
• scp03 command
• setexpr command
• size command
• true command
• ums command