u/CopperShortswordYT

▲ 27 r/chrultrabook+1 crossposts

--EDIT: To clarify, this isn't a "bypass" of the anything. Rather, it's a method to utilize the RW_LEGACY boot within the stock firmware. This allows for a native Linux installation and full hardware initialization while staying within the constraints of the factory-shipped firmware (no WP disabling or custom BIOS flashing required).

To start out, I’ve been working on this for 4 years, starting when I was 13. I got this as a birthday present from a family member who didn’t know otherwise, and I wanted to make it work. I managed to do it yesterday out of random impulse lol. I’ll provide steps to reproduce below.

1. Installation Media: Flash a USB with Debian 12 (Bookworm).

2. Developer Mode: Enable ChromeOS Developer Mode.

3. Crossystem Flags: In the terminal (Ctrl+Alt+F2/Right Arrow), run:sudo crossystem dev_boot_usb=1 sudo crossystem dev_boot_legacy=1

4. Booting: Restart and press Ctrl + L at the splash screen to use the alternate bootloader. Select your Debian USB.

5. Installation: I installed all files in one partition with the XFCE desktop and standard utilities.

6. GRUB Config: Once installed and logged in, run sudo nano /etc/default/grub.

7. Kernel Flags: Change GRUB_CMDLINE_LINUX_DEFAULT to:

"quiet splash rootwait nvme_core.default_ps_max_latency_us=0"

8. Update: Run sudo update-grub and restart.

Note: If you get stuck, use the GRUB terminal to boot manually:

set root=(hd0,gpt2)
linux /vmlinuz root=/dev/mmcblk0p2 rw bootdelay=20
initrd /initrd.img
boot

9. Audio Fix

Credit goes to https://forums.linuxmint.com/viewtopic.php?t=459749 for helping me figure it out!

sudo apt update
sudo apt install pipewire-audio-client-libraries pipewire-pulse wireplumber pavucontrol pulsemixer -y
systemctl --user --now enable pipewire pipewire-pulse wireplumber

- Plug an AUX cable or headphones into the jack. This "wakes up" the Jasper Lake controller so the OS can see it.

- Now, open pavucontrol (Volume Control).

- Go to the Configuration tab.

- Set the Jasper Lake device to Pro Audio.

- Jasper Lake HD Audio Pro: Maps to the internal laptop speakers

- Jasper Lake HD Audio Pro 1: Maps to the audio jack

This method has no functionality issues based on testing on my device so far. It includes:

- Working audio.

- No disappearing mouse.

- Multiple monitors.

- Hibernating.

- Suspending.

- Functional power options menu.

- Proper lid close behavior.

(saying this because it was an issue with running Linux Distros on my Chromebook before)

u/CopperShortswordYT — 17 days ago