From coreboot
Revision as of 23:09, 12 June 2013 by Timisch (Talk | contribs) (Start)

Jump to: navigation, search

Flashing your own Coreboot-version and Payload onto your device is do-able, but requires some hardware preperation and ignorance in warning messages.


A good place to start is the Chromium site. They have guides howto set your Chromebook into developer-mode and howto disassemble your device.

Both things will be nessary, if you want to flash your own version of Coreboot onto your Chromebook (in-system). It is nessary to close a circuit on the motherboard via either a switch, jumper or srew to disable the write-protection of the spi chip. And to use the flashing tool flashrom in ChromeOs, you have to be in the developer-mode. If you already installed a Gnu/Linux-system or likely you can also use the flashrom from there (but then you would be in developer-mode anyway).

Note: The first three Chromebooks are not supported by coreboot at the moment, but flashrom should be working. Mario, Alex and ZGB are running Insyde H2C some UEFI. Snow has das U-Boot nativly installed, but a coreboot port is available. All the others come shipped with Coreboot.

Release date Manufacturer Model Project Code Name Disassembly guide Close cicuit via Location for Jumper/Screw SPI-Chip
May 2012 Samsung Series 3 Chromebox Stumpy Jumper between the Battery and Ram
May 2012 Samsung Series 5 550 Chromebook Lumpy Jumper between the Battery and Ram
October 2012 Samsung ARM Chromebook Snow (aka Daisy) Screw next to usb3.0-port
November 2012 Acer C7 Chromebook Parrot Jumper between CPU and Fan under plastic
January 2013 Lenovo Thinkpad X131e Chromebook Stout  ?
February 2013 HP Pavilion 14 Chromebook Butterfly Switch rightside behind the usb-ports
February 2013 Google Chromebook Pixel Link Screw

General Hardware Preperation

Use the disassembly guides to disassemble your Chromebook till you see the place were you can put on a jumper or screw in a bolt. Check the out the pictures in the disassembly guides to find the right spot. Either screw or plug on now. For example in Lumpy and Stumpy you have to put a jumper on place between the Battery and Ram next to the Keyboard-Connector. Now assemble again (follow the guide). Now you are ready to flash your own Coreboot-version onto your Chromebook.

Building your own Coreboot-version and Payload

First, you cannot do that inside the ChromeOS. Use your GNU/Linux-system and follow the Build HOWTO.

Recovery/external programming

Ok, you fucked things up, but on the other hand this will give you the oppotunity to learn external chip-programming, so cheer-up. First you will need to locate the SPI-Chip. If you done that you will need an external flashrom programmer (for example the open-hardware tool Bus Pirate). At the moment ask at the coreboot/flashrom mailing list for further details.