OpenWrt RecoveryOS for the Z2

WARNING: Do not run the z2uflasher script from z2lite. The flash script is not working properly with it. Until I figure out what the problem is, I recommend using z2sid or openwrt to flash an already u-booted Zipit. 

UPDATE: anarsoul has merged the linux 3.2 kernel into projectgus' OpenWrt repo. This means that the package repo from chainxor.org will no longer contain 3.0 kernel module patches for this openwrt recovery os. The recovery os itself will still work fine, but you should not try to install kernel modules packages with opkg. I will either make my own repo or rebuild the recovery os with the newer 3.2 kernel.

UPDATE: There seems to be a problem with the conservative cpu speed governor causing freezing of the Zipit. This is the default governor I have set in OpenWRT so you should change this to something else like "userspace" in /etc/init.d/z2-cpuspeed.

Projectgus released his port of OpenWrt for the Zipit recently and I've been working to get it into the flash on the Zipit. OpenWrt is pretty small on it's own so it wasn't too difficult to get it to fit in the measly amount of flash memory available.

There was a minor hurdle to overcome. The current mainline Linux kernel's partition setup is

mtdblock0 - u-boot
mtdblock1 - u-boot environment
mtdblock2 - Flash
mtdblock3 - u-boot splash

This allowed for a kernel with initramfs to be placed into the "Flash" partition which is great, but the initramfs remains the same after reboot. You are not able to save anything except to an sd card. To overcome this issue I added a patch to the OpenWrt kernel source that redefines the mtd partition layout. The new layout is

mtdblock0 - u-boot
mtdblock1 - u-boot environment
mtdblock2 - Kernel
mtdblock3 - Filesystem
mtdblock4 - u-boot splash

With this setup you can put the kernel in a partition by itself and put a rootfs in another. The OpenWrt rootfs I used is JFFS2 which can be chosen in the OpenWrt menuconfig. The only change here is splitting the old "Flash" mtdblock2 into a 2mb Kernel and 5.8mb Filesystem partition. A word of warning with this new setup; if you boot a kernel from sd card with the older partition layout you should be careful about writing to mtdblock2.

The first time you boot into the OpenWrt RecoveryOS it will ask you for a new root password and for the MAC address of the Zipit. The MAC is located under the battery and should be entered as shown on the sticker including the colons.

The rootfs is pretty basic but has most everything you'd need from a limited linux system. On top of the typical stuff I've added nano, tmux and elinks browser. I've also added some of the usual Zipit specific scripts for backlights and wifi. There is an init script that will automount all partitions on an sd card to /mnt if found at boot. Be aware that if your sd card has the uboot.script it will boot from the sd and not the recovery os. Just rename the uboot.script to boot recovery.

Check out the readme after bootup for more info.

To flash the new recoveryos, download the new uflasher to your Zipit or sd card and run the correct flash script (see the readme). For you Zipit veterans this is the same flash script I've used in the past. I don't have a FlashStock version yet (you can replace the mtdblock.bak and flash.def files in the latest FlashStock with the ones from this tarball).

Flashstockv0.1.2_openwrt.zip
z2uflasher_openwrt_20111127.tar.bz2

Projectgus' OpenWrt Source
Mozzwalds OpenWrt Source