The Fedora ARM Project provides a Beta root-disk for Fedora 13. Downloading the .tar.bz2 and extracting it to the first partition (formatted as ext3) of an USB-disk should make a good start for any Pogoplug related development.
The bootloader (u-boot) has been updated according to the well written instructions (includes a script for automation) from Jeff Doozan. The instructions are mainly targeted for Debian, but are a very useful source of information. Using the script, the bootloader gets replaced and it is possible to boot from an external USB-disk when placing the kernel (uImage) and initrd.img (uInitrd) under /boot on the USB-disk.
There is a kernel with initrd.img and modules available for ARM/Kirkwood boards. Unfortunately this kernel does not seem to fully boot on the Pogoplug. As there is no monitor or serial port connector on the outside of the pink box (who knows whats hidden inside), troubleshooting a boot issue is quite challenging. The updated u-boot supports netconsole. The output over netconsole shows that the kernel and initrd.img are loaded correctly and can be started. After which the kernel is supposed to take over the communication with any human being (or machine for that matters). Unfortunately the installation does not seem to get to a point where logs are written (checking the removable USB-storage after trying to boot). There is also no networking happening, eventhough the rootfs has been configured for DHCP.
Luckily there is an other kernel available for a GuruPlug (which is also a similar ARM board) which should function on any ARM/Kirkwoood. This specific kernel does not use an initrd/initramfs, so when trying to boot it, make sure to have only a /boot/uImage and no /boot/uInitrd. Booting a Pogoplug with the GuruPlug kernel-22.214.171.124 seems to work well:
Linux version 126.96.36.199 (root@Xion) (gcc version 4.4.1 (Sourcery G++ Lite 2010q1-202) ) #1 PREEMPT Mon Nov 29 06:21:49 EST 2010 CPU: Feroceon 88FR131  revision 1 (ARMv5TE), cr=00053977 CPU: VIVT data cache, VIVT instruction cache Machine: Marvell SheevaPlug Reference Board Memory policy: ECC disabled, Data cache writeback On node 0 totalpages: 65536 free_area_init_node: node 0, pgdat c058a5f4, node_mem_map c065e000 Normal zone: 512 pages used for memmap Normal zone: 0 pages reserved Normal zone: 65024 pages, LIFO batch:15 Built 1 zonelists in Zone order, mobility grouping on. Total pages: 65024 Kernel command line: console=ttyS0,115200 root=/dev/sda1 rootwait rootfstype=ext2 mtdparts=orion_nand:1M(u-boot),4M(uImage),32M(rootfs),-(data) PID hash table entries: 1024 (order: 0, 4096 bytes) Dentry cache hash table entries: 32768 (order: 5, 131072 bytes) Inode-cache hash table entries: 16384 (order: 4, 65536 bytes) Memory: 256MB = 256MB total Memory: 253380k/253380k available, 8764k reserved, 0K highmem ...