Get,Set=1,Set=0,Option,Description
cmd_get,cmd_true,cmd_false,console,PC BIOS & EFI console
cmd_get,cmd_true,cmd_false,serial,Serial terminal
cmd_get,cmd_true,cmd_false,ofconsole,Open Firmware Console
cmd_get,cmd_true,cmd_false,at_keyboard,PC AT Keyboard (Coreboot)
cmd_get,cmd_true,cmd_false,usb_keyboard,USB Keyboard (HID Boot protocol)