Mark's Blog

This is how I installed Gentoo on the SheevaPlug:

First I’ve made some preparations to decrease overall installation time:

• Setup a cross-compiling suite for the SheevaPlug.
  You can compile the Linux kernel parallel to installing GNU/Gentoo.
• Get an USB drive or SD flash card.
  Although the Linux kernel will be written to flash we will install Gentoo on that external device.
  Of course you could install the latter on flash, too. Just stop following the instructions when it says “eix-sync” or “emerge –sync” and use /dev/mtdblock2 (jffs2 filesystem, though) where it says /dev/sda2.
  Applies analogously to SD card installation.
• Make sure you can network boot the SheevaPlug.
  You could boot the pre-installed Debian and even skip compiling a new kernel, though.

Step 0: boot an installation system

Either boot the pre-installed Linux or network boot the SheevaPlug. I have done the latter.

Make sure you have access to the internet and /dev/null is writable by all:

# if eth0 doesn't work, try eth1
ifconfig eth0 192.168.1.13 up
# check whether the nameserver is correct
nano /etc/resolv.conf
# provide the IP of your router
route add default gw 192.168.1.1
chmod a+rw /dev/null

Step 1: prepare the destination medium

x means press Enter, leave out what is behind the octothorpe (#):

fdisk /dev/sda
p
d
n 1 x +2GB   # /dev/sda1, SWAP
n 2 x +8GB   # /dev/sda2, ROOT
n 3 x +300MB # /dev/sda3, LOG
n 4 x x      # /dev/sda4, PORTAGE
t 1 82       # SWAP
a 2          # BOOT
w

mkswap /dev/sda1
swapon /dev/sda1

mkfs.ext3 -L ROOT /dev/sda2
mkfs.ext3 -L LOG /dev/sda3
mkfs.ext2 -j -N 2000000 -L PORTAGE /dev/sda4

If you happen to install on a SD card, replace ext3 by ext2. The filesystem journal will be often maintained at one storage-cell of the card wearing it out, what in turn will cause filesystem corruption. Therefore I advice using the unjournalled ext2 in that case.

Step 2: extract a Gentoo tarball

You can find Gentoo tarballs with a basic system (called stage 3) at the Gentoo mirrors’ page, descending into releases/arm/current-stage3/armv5tel-softfloat-linux-gnueabi/ e.g. here or there. Select a tarball, copy its link.

mount /dev/sda2 /mnt/gentoo
cd /mnt/gentoo
wget -O - http://...the-link.../stage3-armv5tel-20100220.tar.bz2 | tar -xjp

This will extract the tarball immediately, i.e. as it gets downloaded without storing it on the plug.

Step 3: chroot into Gentoo

Create folders for the remaining partitions (sda1 is swap, sda2 is root!) and insert their list into /etc/fstab:

mount -t proc none /mnt/gentoo/proc
mount -o bind /dev /mnt/gentoo/dev
mount /dev/sda3 /mnt/gentoo/var/log
mkdir -p /mnt/gentoo/usr/portage
mount /dev/sda4 /mnt/gentoo/usr/portage
mkdir -p /mnt/gentoo/var/tmp
mount --bind /tmp /mnt/gentoo/var/tmp
mount --bind /tmp /mnt/gentoo/tmp

cp -L /etc/resolv.conf /mnt/gentoo/etc/

chroot /mnt/gentoo /bin/bash
env-update
source /etc/profile
export PS1="(chroot) $PS1"

nano /etc/fstab

You can see my fstab here.
After that (still in chroot) we will select profile, the languages our system will run and chose suitable compile settings for the architecture:

cd /etc
ln -snf ../usr/portage/profiles/default/linux/arm/10.0 /etc/make.profile
nano locale.gen
ln -s portage/make.conf
nano make.conf

Here you can download my locale.gen and make.conf. Just remember to remove feature distcc because we have not installed it yet.

Step 4: kernel and preparations for first boot

You should have already compiled an kernel by now. See this post for configuration file and how to do it. Of course, you could use the pre-installed kernel, but I have not tested whether that will work.
Compile and copy the Linux kernel as described to your SheevaPlug.

Unless you like the serial console, have SSH be run on system startup. Don’t forget to set a root password:

passwd
rc-update add sshd default
nano /etc/conf.d/local.start

nano -w /etc/inittab
# (Uncomment the line and replace 9600 by 115200 so it reads:)
s0:12345:respawn:/sbin/agetty 115200 ttyS0 vt100
# (remove all conventional TTYs)

nano -w /etc/conf.d/hostname
cp /usr/share/zoneinfo/Europe/Berlin localtime

Step 5: fetch ebuilds and packages

If you installed Gentoo on the system flash and if you have no dedicated device for portage, skip this step.
You will have to install a DHCP client by hand or configure static IP. Else we will utilize portage for former:

emerge --oneshot eix
eix-update
eix -cI
emerge udhcp
nano /etc/conf.d/net
# ...
cd /etc/init.d
ln -s net.lo net.eth1

See my net file. Remember to replace 192.168.1.2 by your nameserver in case it didn’t already get provided by DHCP.
On some SheevaPlugs – even of the same revision – eth0 is eth1, therefore I make that additional softlink in the last line.

I tend to grab the portage overlays from my workstation. But you can also skip this:

mkdir -p /usr/local/overlays
cd /usr/local/overlays
rsync -azuv -e ssh 192.168.1.6://usr/local/overlays/* /usr/local/overlays/

Step 6: exit chroot environment and restart the SheevaPlug

exit
cd /
umount /mnt/gentoo/usr/portage
umount /mnt/gentoo/var/log
umount /mnt/gentoo/var/tmp
umount /mnt/gentoo/tmp
umount /mnt/gentoo/proc
umount /mnt/gentoo/dev
umount /mnt/gentoo
exit

Step 7: set boot parameters

You’re almost done. The last thing is to tell the SheevaPlug to boot Linux and the latter to use the correct root device. Therefore reset (or shutdown -r now) your plug and get into the u-boot shell:

setenv bootcmd usb start\;nand read 0x01000000 0x00100000 0x00400000\;setenv bootargs $(console) root=/dev/sda2 rootdelay=10\; bootm 0x01000000
saveenv
reset

Keep yor fingers crossed. Linux kernel should boot into GNU/Gentoo on /dev/sda2 (or your SD card, if you changed /dev/sda; or the vintage Debian if you changed it into /dev/mtdblock2).

Now you could install distcc for distributed cross-compiling and customize your Gentoo Linux!

Bookmark to:

Tags: embedded, Gentoo, GNU/Linux, know-how, SheevaPlug