09-22-2019, 02:26 PM
the boot order Luke mentiones is ROM code boot order. it's where it gets firmware to load into SRAM. NVMe is not handled by it. what you ask is up to FW in question - uboot here, which is not FW, but eh, it is there instead of FW. generally you configure uboot through scripting what storage it should consider as an OS boot source and in what order.
ANT - my hobby OS for x86 and ARM.