USB Boot for Raspberry Pi

Prerequisite

Before you can boot a rPi from USB you will need to update the eeprom if it has not already been done. As of writting any new rPi will need to be updated. Write an SD card to boot the rPi so the eeprom can be updated.

Make sure everything is updated.

apt update
apt -y full-upgrade
apt -y dist-upgrade
apt -y autoclean
apt -y autoremove

eeprom

Display Current Version

 rpi-eeprom-update 

Example:

   CURRENT: Thu 29 Apr 16:11:25 UTC 2021 (1619712685)
    LATEST: Thu 29 Apr 16:11:25 UTC 2021 (1619712685)
   RELEASE: default (/lib/firmware/raspberrypi/bootloader/default)
            Use raspi-config to change the release.

  VL805_FW: Dedicated VL805 EEPROM
     VL805: up to date
   CURRENT: 000138a1
    LATEST: 000138a1

Update

  rpi-eeprom-update -a 

Boot Order

By default the Pi will boot to USB then fall back to SD card. If both fail the system will then reboot and repeat the cycle.

To change the order.

 rpi-eeprom-config --edit 

Codes

Value	Mode	Description
0x1	SD CARD	SD card (or eMMC on Compute Module 4)
0x2	NETWORK	Network boot
0x3	USB DEV	USB device boot – See usbboot (since 2020-09-03)
0x4	USB MSD	USB mass storage boot (since 2020-09-03)
0xe	STOP	Stop and display error pattern (since 2020-09-03). A power cycle is required to exit this state.
0xf	RESTART	Start again with the first boot order field. (since 2020-09-03)

Examples

Boot Order	Description
0xf41	Try SD first, followed by USB-MSD then repeat (default if BOOT_ORDER is empty)
0xf14	Try USB first, followed by SD then repeat
0xf21	Try SD first, followed by NETWORK then repeat
0x1	Try SD. If Fail do nothing. Cold reboot to try again.

Create HDD

Once the above has been done write and existing SD card to a USB hard disk or just write your image of choice. You can use Win32diskImager to write the SD card to a file and then the file to the hard disk.

Reference

Official Raspberry Pi documentation.

• eeprom
• bootloader
• LED Flash Codes