Wiki

• FrontPage
• RecentChanges
• FindPage
• HelpContents
• ARMChromebook

Translation(s): none

Models covered
Samsung Chromebook XE503C12 (the 2012 ARM one)

Sub-models options :
- CPU: Samsung Exynos5 Dual
- Video card: Mali T604
- Screen size: 11.6"

Overall Status

Legend :
= OK ; Unsupported(No Driver) ; = Error (Couldn't get it working); [?] Unknown, Not Test ; [-] Not-applicable
= Configuration Required; = Only works with a non-free driver and or firmware

Important Note

There are several methods of installation other operating systems on Chromebook.

TODO: add some information about them

Installing to an SD card using the ChromeOS kernel

This approach requires the enabling of both Developer Mode and USB/SD card boot. It uses the ChromeOS kernel and modules rather than the normal Debian kernel.

First, we prepare the SD card on a desktop machine. These instructions are for an 8G card, which affects on the third cgpt add call - you can adjust as required.

Three partitions are created on the disk. In time, the intention is that these be used for:

1. a copy of nv-uboot that is chainloaded by the standard firmware,

2. a /boot filesystem containing the standard (non-ChromeOS) kernel, read by nv-uboot,

3. the root filesystem.

Currently nv-uboot is not used, and so the arrangement is:

1. a copy of the ChromeOS kernel that is loaded by the standard firmware,

2. a /boot filesystem that is used only to contain the ChromeOS kernel (which is not used during booting, just during the preparation of the previous partition),

3. the root filesystem.

# On a desktop machine (does not need to be ARM):
#
DEV=/dev/mmcblk0
MNT=/mnt
# Partitioning the device:
parted --script ${DEV} mklabel gpt
cgpt create ${DEV}
cgpt add -t kernel -l uboot/kernel -b 34 -s 16384 ${DEV}
cgpt add -t data -l /boot -b 16418 -s 32768 ${DEV}
cgpt add -t data -l / -b 49186 -s 15474621 ${DEV}
blockdev --rereadpt ${DEV}
# Create the boot filesystem:
mkfs.ext2 ${DEV}p2
# Create the root filesystem:
mkfs.ext4 ${DEV}p3
# Install the bootstrap packages in the root filesystem:
mkdir -p ${MNT}
mount ${DEV}p3 ${MNT}
mkdir -p ${MNT}/boot
mount ${DEV}p2 ${MNT}/boot
debootstrap --arch=armhf --foreign jessie ${MNT} http://httpredir.debian.org/debian
# Unmount the filesystems:
umount ${MNT}/boot
umount ${MNT}

Now move the SD card to the Chromebook which is already booted with ChromeOS:

# On the Chromebook:
#
DEV=/dev/mmcblk1
MNT=/mnt
# Unmount from wherever ChromeOS decided to mount the device,
# remount where we want:
umount ${DEV}p2
umount ${DEV}p3
mount ${DEV}p3 ${MNT}
mount ${DEV}p2 ${MNT}/boot
# Complete the bootstrap:
chroot ${MNT} /debootstrap/debootstrap --second-stage
# Set up fstab:
cat > ${MNT}/etc/fstab <<EOF
${DEV}p3 / ext4 errors=remount-ro 0 1
${DEV}p2 /boot ext2 errors=remount-ro 0 1
EOF
# Set up the apt sources and update:
cat > ${MNT}/etc/apt/sources.list <<EOF
deb http://httpredir.debian.org/debian jessie main non-free contrib
deb-src http://httpredir.debian.org/debian jessie main non-free contrib
EOF
# Update the package list:
chroot ${MNT} apt-get update
# Install useful packages:
chroot ${MNT} apt-get install -y cgpt vboot-utils \
        vboot-kernel-utils
chroot ${MNT} apt-get install -y wicd-daemon wicd-cli \
   wicd-curses console-setup
# Set the root password to blank:
chroot ${MNT} passwd -d root
# Set the hostname:
echo "wowbagger" > ${MNT}/etc/hostname
# Guess which kernel partition is the latest.  Run cgpt show and see
# which one (KERN-A or KERN-B) has the highest priority.
cgpt show /dev/mmcblk0
# Copy the ChromeOS kernel partition to the root filesystem.  In this example
# we'll assume it was KERN-B:
dd if=/dev/mmcblk0p4 of=$MNT/boot/oldblob
# Declare the kernel flags:
cat > ${MNT}/boot/kernel.flags <<EOF
console=tty1 printk.time=1 nosplash rootwait root=${DEV}p3 rw rootfstype=ext4 lsm.module_locking=0
EOF
# Sign the kernel:
cat > ${MNT}/boot/sign-kernel.sh <<EOF
vbutil_kernel --repack /boot/vmlinuz.signed --keyblock \
  /usr/share/vboot/devkeys/kernel.keyblock --version 1 \
  --signprivate /usr/share/vboot/devkeys/kernel_data_key.vbprivk \
  --config /boot/kernel.flags --oldblob /boot/oldblob
EOF
chroot ${MNT} sh /boot/sign-kernel.sh
# Write the signed kernel to the KERN-C partition:
dd if=${MNT}/boot/vmlinuz.signed of=/dev/mmcblk0p6 bs=4M
# Mark the newly written kernel partition as good and set the
# priority:
cgpt add -i 6 -S 1 -P 5 /dev/mmcblk0p6
# Copy the ChromeOS kernel modules into the root filesystem:
mkdir -p ${MNT}/lib/modules
cp -r /lib/modules/* ${MNT}/lib/modules
# Copy the non-free firmware for the wifi device:
mkdir -p ${MNT}/lib/firmware/mrvl
cp /lib/firmware/mrvl/sd8797_uapsta.bin ${MNT}/lib/firmware/mrvl
# Umount the filesystems:
umount ${MNT}/boot
umount ${MNT}

You should now be able to reboot your system and press Control-U at the boot screen to boot from the SD card. There is no root password - you should set one.

A downloadable image of the end result is available. Uncompress this and write it to an 8G SD card. At the command line:

gunzip debian-chromebook.20130625.img.gz
dd if=debian-chromebook.20130625.img of=<PUT YOUR OUTPUT DEVICE HERE>

Notes

• wicd-curses needs a patch to be useful as of 2013-06-19. (Not required as of 2013-06-25.)

• This same sequence of steps using a USB flash drive instead of the SD card failed to boot for reasons currently unknown.

• [20140615 vincent@zweije.nl] According to http://forums.debian.net/viewtopic.php?t=103468 /boot has been done away with. The kernel must be recovered from the appropriate kernel partition. See there for how to.

Configuration

Display

There is a driver for X11: xf86-video-armsoc. It was created from xf86-video-omap one but forked quite long time ago. There is armsoc driver at Linaro git server but it does not have Mali T604 support at all.

Xorg.conf snippet (taken from Chromium OS):

Section "Device"
        Identifier      "Mali FBDEV"
        Driver          "armsoc"
        Option          "fbdev"                 "/dev/fb0"
        Option          "Fimg2DExa"             "false"
        Option          "DRI2"                  "true"
        Option          "DRI2_PAGE_FLIP"        "false"
        Option          "DRI2_WAIT_VSYNC"       "true"
#       Option          "Fimg2DExaSolid"        "false"
#       Option          "Fimg2DExaCopy"         "false"
#       Option          "Fimg2DExaComposite"    "false"
        Option          "SWcursorLCD"           "false"
EndSection

Section "Screen"
        Identifier      "DefaultScreen"
        Device          "Mali FBDEV"
        DefaultDepth    24
EndSection

OpenGL ES

To get OpenGL ES working several files from Chromium OS needs to be copied from /usr/lib/:

• libmali*
• libEGL*
• libGLES*

There is a package in my Ubuntu PPA which automates it and provides everything to get it working instead of Mesa. Did not tested under Debian yet.

Audio

Add to /etc/pulse/default.pa the following line :

• load-module module-alsa-sink device=sysdefault

Touchpad

ChromeOS uses a driver called cmt which is not packaged in Debian (and also has some extra unpackaged dependencies). Using the synaptics driver with the following configuration will give you a similar experience as the one under ChromeOS:

Section "InputClass"
  Identifier "touchpad"
  MatchIsTouchpad "on"
  Driver "synaptics"
  Option "FingerLow"     "1"
  Option "FingerHigh"    "2"
  Option "MaxSpeed"      "6"
EndSection

Power Management

Suspend to memory works but looks like battery usage is higher than expected.

Not tested hibernation.

WiFi

Works fine.

System Summary

lsusb

lsusb -v | grep -E '\<(Bus|iProduct|bDeviceClass|bDeviceProtocol)' 2>/dev/null

Bus 001 Device 002: ID 0424:3503 Standard Microsystems Corp.
  bDeviceClass            9 Hub
  bDeviceProtocol         2 TT per port
  iProduct                0
  bDeviceClass            9 Hub
  bDeviceProtocol         0 Full speed (or root) hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  bDeviceClass            9 Hub
  bDeviceProtocol         0 Full speed (or root) hub
  iProduct                2 S5P EHCI Host Controller
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
  bDeviceClass            9 Hub
  bDeviceProtocol         0 Full speed (or root) hub
  iProduct                2 EXYNOS OHCI Host Controller
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  bDeviceClass            9 Hub
  bDeviceProtocol         1 Single TT
  iProduct                2 xHCI Host Controller
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
  bDeviceClass            9 Hub
  bDeviceProtocol         3
  iProduct                2 xHCI Host Controller
Bus 001 Device 003: ID 2232:1037
  bDeviceClass          239 Miscellaneous Device
  bDeviceProtocol         1 Interface Association
  iProduct                1 WebCam SC-03FFM12339N
      (Bus Powered)
  bDeviceClass          239 Miscellaneous Device
  bDeviceProtocol         1 Interface Association
  (Bus Powered)

Resources

List of loaded modules

Module                  Size  Used by
hidp                   12084  1
isl29018                6412  0
industrialio           14340  1 isl29018
uvcvideo               59681  0
videobuf2_vmalloc       2732  1 uvcvideo
sbs_battery             6441  0
joydev                  8277  0
rfcomm                 21424  12
mwifiex_sdio           11492  0
mwifiex               102827  1 mwifiex_sdio
cfg80211              159128  1 mwifiex
btmrvl_sdio             7952  0
btmrvl                 11681  1 btmrvl_sdio
bluetooth             165503  25 hidp,btmrvl,rfcomm,btmrvl_sdio
spidev                  4304  0

Attachments

Some configuration files and sample outputs.

Useful Links

• official developer page

• page detailing Debian installation, including kernel

Credits

• Marcin Juszkiewicz

• Olof Johansson

• Andrew Wafaa

• Jay Lee