Flash your Android tablet with Ubuntu

How to flash your folio 100 from Toshiba with a fresh Ubuntu build.

Here is a quick method to install Ubuntu 10.10 into a folio 100 tablet (originally android).

First, thanks to all the fox at XDA. More detail at:
  http://ac100.gudinna.com/README/
  http://forum.xda-developers.com/showthread.php?t=907960&page=1
  http://forum.xda-developers.com/showthread.php?t=907960

So far, wifi and touchscreen are broken, i am sure someone will soon take care of this. most important is to have the tools to debug.

Two parts:
  build ubuntu for ARM
  build the kernel and flash it,
  install ubuntu on a SD card.

First we will prepare a rootfs to install in the SD card. It is so handy to do this with the ubuntu tool called roostock. roostock will help you to build a rootfs image for arm, please read the detail at: https://wiki.ubuntu.com/ARM/RootfsFromScratch

# sudo apt-get install roostock # sudo rootstock --fqdn myhostname --login ubuntu --password temppwd --imagesize 4G --seed ubuntu # ls armel-rootfs-201101132334.tgz

Easy, no? Then the kernel, almost that easy. Toshiba GPL kernel can be found at: https://github.com/tsh/folio100, Attached is the kernel config i used, it is inspired from http://forum.xda-developers.com/showthread.php?t=907960

# git clone git://github.com/tsh/folio100.git kernel-folio # cd kernel-folio # export ARCH=arm; export CROSS_COMPILE=arm-linux-gnueabi- # make tegra_harmony_android_defconfig # make menuconfig # make -j16 # ls arch/arm/boot/zImage

To flash this kernel, we will need to include it in a update.zip file and ask the folio boot loader to flash it. The kernel image will be boot.img, it contains a header and a ramdisk (empty for us). This boot.img file is created with the tool mkbootimg (available from cyanogen, as well as unpackbootimg). The boot.img will be simply zipped with a script to do the updated.

Note that here we are telling the kernel to boot on /dev/mmcblk1p1 (sd card) if you plan to boot your system from a usb key, use /dev/sda1 instead in the kernel command line. Attached is an update.zip image ready to be flashed. You can take it as a starting point, remove the boot.img file (with the kernel) and create your own (you will need the attached empty ramdisk file as well):

# unzip update.zip # rm boot.img # mkbootimg --kernel arch/arm/boot/zImage --cmdline "mem=448M@0M nvmem=64M@448M vmalloc=192M video=tegrafb usbcore.old_scheme_first=1 tegrapart=recovery:122000:a00:800,linux:a0e00:1000:800,loader:300:400:800,mbr:700:200:800,system:900:20000:800,cache:20900:80000:800,misc:a0900:400:800,userdata:a1f00:80000:800 boardtype=PR root=/dev/mmcblk1p1 init=/sbin/init usb-storage.delay_use=0 rootdelay=10" -o boot.img --ramdisk boot.img-ramdisk.gz # zip -r update.zip boot.img META-INF

Before you can flash your folio’s kernel partition, be sure you know how to restore a working image (available at http://forum.xda-developers.com/showthread.php?t=846199)

To flash the kernel:
  copy the update.zip file in FAT formated SD card
  insert the SD card in the folio and be sure the folio power cable is plugged
  power on the device and press power and volum-up in the same time
  press volume up to confirm
  press volume down for android update
  press volume up to confirm

From now your device will boot with you custom kernel and try to boot on the SD card.

Insert the SD card in your computer, unmount it, reformat it with a ext3 file system and copy the ubuntu rootfs. Here i assume the sdcard is sdb1, your responsibility to change this. By the way, i had to update /etc/fstab...

# umount /dev/sdb1 # cfdisk /dev/sdb # change the file system type to 83 (linux) and save # mkfs.ext3 /dev/sdb1 # mount /dev/sdb1 /mnt # tar xvzf armel-rootfs-201101132334.tgz --numeric-owner -C /mnt # echo "dev /dev tmpfs rw 0 0" >> /mnt/etc/fstab # umount /mnt

Insert the SD card in the folio and reboot it. Hopefully you can enjoy Ubuntu on your device.

empty ramdisk image :

kernel config for folio 100:

mkbootimg:

unpackbootimg: