mirrexagon / samus-firmware

Building customized firmware for the Chromebook Pixel 2015

samus-firmware

samus is the codename for the Google Chromebook Pixel 2015.

Build and flash EC firmware

• nix build .#chrome-ec-samus
• nix shell .#chrome-flashrom
• sudo flashrom -p ec -w ./result/ec.bin

Update lightbar parameters

Change the default Google colors to the starting colors for the rainbow shift.

• nix shell .#chrome-ec-utils
• sudo ectool lightbar params lightbar/new_params.txt

Update MrChromebox Coreboot firmware to not overwrite EC firmware

• Get a MrChromebox full ROM file, eg. coreboot_tiano-samus-mrchromebox_20220409.rom
• nix shell nixpkgs/nixos-unstable#cbfstool .#chrome-flashrom
• cbfstool <rom file> remove -n ecrw
• cbfstool <rom file> remove -n ecrw.hash
• Flash it with sudo flashrom -n -p host --ifd -i bios -w <rom file>

Resources/links

• MrChromebox custom firwmare:
  • Coreboot: https://github.com/MrChromebox/coreboot
  • EC firmware: https://github.com/MrChromebox/chrome-ec/tree/firmware-samus-6300.B
    • About EC firmware sync, EC firmware is in coreboot CBFS and can be removed to prevent sync: MrChromebox/firmware#335
  • Flashing scripts for reference on how to flash things, preserving parts from original firmware, etc.: https://github.com/MrChromebox/scripts
  • Keyboard function row remapping, can disable via coreboot: MrChromebox/firmware#349

Source: https://www.reddit.com/r/chromeos/comments/7x87dy/anyone_have_spare_parts_for_2015_pixel_or_suggest/

Servo debug board information: https://chromium.googlesource.com/chromiumos/third_party/hdctools/+/HEAD/docs/servo_v2.md