The EspressoBin, like most ARM boards, uses the Das U-Boot bootloader. You’ll need to make the changes in u-boot.
Reboot the board, hit a key to interrupt the automatic boot, and use “printenv” to list the environment variables. You can use “setenv” to change variable values for this boot and “saveenv” to write the new values to persistent storage.
The Marvell kernel/device tree blob does not expose the on-chip NOR flash, unfortunately, so you cannot do this from Linux right now.
