Since the wiki is down, and I recently went through the process of installing ArchLinuxARM on a GuruPlug, here's the guide scavenged from G's cache:
$this->bbcode_second_pass_quote('', '
')Notes
If you can live with 1 ethernet port, we strongly suggest getting a SheevaPlug instead. It's much more stable, runs cooler, and is much more supported by everyone. Also, you'd save on buying the JTAG box (it's built-in on the SheevaPlug).
Wi-Fi should work in client mode - access-point mode has not been tested at all.
Prerequisites
GuruPlug
Linux computer with a TFTP server up and running
Serial cable (Nokia CA-42) or preferably, the GuruPlug JTAG box
Install U-Boot
The GuruPlug's U-Boot bootloader does not support booting from USB. Therefore, before you can run Arch Linux ARM install Linux, you'll need to update the bootloader.
You will need a computer with a TFTP server turned on on the same network as your GuruPlug.
Download a better U-Boot (with USB booting and ext filesystem booting enabled from Slackware) to your Linux box, NOT to your GuruPlug:
$this->bbcode_second_pass_code('', 'cd /tftpboot
wget http://Arch Linux ARM.com/os/guruplug/guruplug-u-boot.bin
chmod 777 guruplug-u-boot.bin')
Run the following after stopping the automatic U-Boot boot loading process (replacing the serverip to your Linux TFTP server and ipaddr to the GuruPlug's requested IP address):
$this->bbcode_second_pass_code('', 'Marvell>> setenv ipaddr 192.168.1.123
Marvell>> setenv serverip 192.168.1.106
Marvell>> tftpboot 0x0800000 guruplug-u-boot.bin
Marvell>> nand erase 0x0 0xa0000
Marvell>> nand write 0x0800000 0x0 0xa0000
Marvell>> reset')
You'll need to make sure you bootcmd contains a "usb start", that it ext2load's /boot/uImage from usb 0:1, and that there's a root=/dev/sda1 kernel parameter. You might want to add a rootdelay=5 in there too. As mentioned above, we have no idea what the variables of the Slackware U-Boot are or which ones work. Please update with more information.