Installation on Baytrail ChromeOS devices can be performed in either a dual boot or standalone setup. A standalone setup is one in which GalliumOS is installed on the internal storage, replacing ChromeOS, or installed to external media (SD, USB flash, USB-attached SSD) leaving ChromeOS on the internal storage untouched; a dual boot setup is one in which GalliumOS is installed to the internal storage alongside ChromeOS, and the user can choose between them via keyboard shortcuts on the developer mode boot screen.
Since Baytrail devices do not ship with any legacy boot capability, a firmware update is required in order to run GalliumOS (or any other OS besides ChromeOS) regardless of configuration.
Create the USB drive
Switch to Developer mode
Switching to developer mode (as opposed to standard / verified boot mode) allows more control over the device/OS, and is required in order to run GalliumOS. Switching to/from developer mode will wipe the device, so ensure anything important is backed up first.
- Shutdown the Chromebook
- Hold ESC+Refresh+PWR to boot the machine into recovery mode
- * You will see a screen with a "Chrome OS is missing or damaged" warning - DON'T PANIC ;)
- Press CTRL+D
- You will see a message asking if you want to enable developer mode / turn OS verification off - Press ENTER to confirm
- Wait for Powerwashing to complete (this will take a few minutes)
- Once Powerwashing is complete, your device will reboot and you will see the white developer mode boot screen, complete with warning that OS verification is off
- *Do not press enter/space to re-enable it, simply press CTRL+D to bypass the 30s timeout and boot ChromeOS (this timeout can be changed later).
Install Legacy Boot capability
- At the ChromeOS login screen, ensure a network connection is set up, but do not log in to ChromeOS
- Open a crosh shell via CTRL+ALT+[RIGHT ARROW]
- Login as 'chronos' (no password is required)
- Download and run the firmware update script for the type of firmware you want to install
- Install either the RW_LEGACY or BOOT_STUB firmware update
- * Note: if you install the RW_LEGACY firmware update, you may also want to change the default boot type (ChromeOS or legacy) and/or boot timeout, which can be done via the same script used to install the firmware update.
- Insert install USB created above (use USB2 port if device has both USB2 and USB3 ports)
- If you installed the RW_LEGACY firmware update and didn't set legacy boot as the default, press CTRL+L to boot in legacy mode
- On the SeaBIOS boot screen, press ESC when prompted to show the boot menu
- Select GalliumOS USB to boot
- If the Grub boot menu appears, press enter to boot in live mode
- Launch installer
- Select 'mmcblk0' if installing to internal storage, or whatever external media you wish to install to
- Perform install, reboot and remove media when instructed.
- Enjoy GalliumOS!