Running Meego Handset in an N900 chroot with Easy Debian: Part 1

I would like to document my process for getting Meego Handset to run in a Maemo chroot on the N900 using Easy Debian, so you don't have to multi-boot your phone.

But I can't document everything in one post, and I'm documenting as I go, so this first post will be the just first steps: how to get an Easy Debian compatible image out of the raw Meego images that the Meego project is posting.

I do these first steps on an Ubuntu desktop machine.

1. Download the latest Meego Handset image. I got mine from the builds directory of the Meego repository, here:  http://repo.meego.com/MeeGo/builds/

The file you are looking for ends in .raw.bz2 and you can get to it by choosing the biggest numbered directory twice, then going into .../handset/images/meego-handset-armv7l-n900/  and downloading the .raw.bz2 file.

This is the one I'm using.

2. Unzip the file on your Linux machine.

I recommend becoming root for the entirety of this procedure. I suggest doing it before you even unzip the file. I had problems unzipping the file as a regular user, and this may have been my problem; I don't know, but what can it hurt to gain root right away?

sudo su -

Unzipping the file is pretty straightforward on a Linux command line:

bunzip2 meego-handset-armv7l-n900.raw.bz2

In these instructions, I'm going to call the meego file "meego-handset-armv71-n900"; substitute the longer version as necessary.

3. Mount the Meego rootfs partition on loop. This is tricky, because the raw image has multiple partitions and so you have to use a little trick I found on the 'Net, here.

a. You need to first create a directory to mount on. I created /media/meego:

mkdir /media/meego

b. Now mount the first partition. First check to see where the partition starts:

fdisk -lu meego-handset-armv7l-n900.raw

See where the first partition starts. Multiply that number by 512, and use it as the offset. In my case, it starts at 1 so the calculation is easy. It is just 512. This will probably stay the same for future releases, but it might change. Better to document this, just in case.

mount -o loop,offset=512 meego-handset-armv7l-n900.raw /media/meego

4. Now make a new image file that will just have the Meego rootfs in it, so it can be mounted properly by Easy Debian. I made my image 1GB, but you can make it bigger if you want.

dd if=/dev/zero of=meego_1_1.img.ext3 bs=1024 count=0 seek=$[1024*1000]

You have to format the new image file! I used ext3.

mkfs.ext3 -m0 -L meego1_1 meego_1_1.img.ext3

5. Mount the new empty image file. I made a mount point, /media/meego2, but you can use whatever name you want.

mkdir /media/meego2

mount -o loop meego_1_1.img.ext3 /media/meego2

6. Copy the Meego rootfs to the new image file you created. Substitute the correct directories here.

cd /media/meego

tar -cf - . | ( cd /media/meego2 ; tar -xpvf - )

7. Unmount everything.

umount /media/meego

umount /media/meego2

8. Copy your new Easy Debian compatible image file to your N900. I would suggest using the USB cable, but there are lots of ways to do this. You can also zip up your file to keep a safe backup.

Next post:

I'll try to post again soon with directions for getting the Meego Handset UI started under Easy Debian's Xephyr nested X server.