The EEPROM can be updated from Raspberry Pi OS using the
sudo rpi-eeprom-update -a reboot
Boot order is controlled by the
BOOT_ORDER EEPROP configuration option. It can be set with
sudo -E rpi-eeprom-config --edit. Up to eight options may be tried, each expressed as a nibble (4 bits), for a total of 32 bits. Option values can be found in the documentation.
config.txt file on the
/boot partition is used to store settings typically found in BIOS/EFI.
vcgencmd get_config <[value|int|str]> prints the active value for a configuration.
The grammar is fairly simple:
- Settings are expressed in
include filename.txtincludes an additional file.
- Conditional filters scope settings to specific hardware, and can be combined (
AND) by listing them one after the other:
[all]resets all previously used filters.
[none]prevents matching any hardware.
[EDID=edid]match specific display output EDIDs
[0x1234abcd]matches a specific serial number.
[gpio<n>=<0|1>]match if the numbered GPIO pin is in a high/low state.
A build of the TianoCore EDK2 is available for the Raspberry Pi 4. These require setting a custom
armstub value in