What's the means of the parameter when generate the Bootloader Payload Update (BUP)

What’s the means of the parameter below when generate the Bootloader Payload Update (BUP),and How could I get the value for a new board.
FAB
BOARDID
BOARDSKU
BOARDREV

Hi,

Run this command on your device can tell you the info.

sudo nv_bootloader_payload_updater --print-ver