Here is my recipe for getting armedslack-current (about 13.1) working on a SheevaPlug. My procedure differs a little from the official instructions, because I think my way was much easier.
I didn't have to set up a PXE/TFTP/NFS environment, which is a pain if you don't already have them.
First hurdle was my Sheeva did not come with a CD, so I had to download the difficult-to-find Windows support tools from
http://www.plugcomputer.org/index.php/us/resources/downloads?func=startdown&id=44. I was then able to use the USB/serial connection to verify the Sheeva booted OK with the stock Linux install.
For Slackware, I used an SD card for my boot device and a USB hard drive for the root fs. I originally tried an old 64MB MMC (not SD, but actual MMC) but u-Boot's 'mmcinit' did not recognize it so I had to switch to a 1GB SD card. My reason for using an MMC/SD was because of many reported problems with a USB boot device not being ready. Rather than deal with this with u-Boot workarounds and sleep/waiting in the bootup scripts, I simply used Windows to format my SD card with FAT and then dropped the kernel and the two Slackware initial ramdisks on it -- one initrd for the installer, one for normal booting. One thing to mention is I renamed the installer initrd file, because the default name is easily confused with the standard initrd.
I also prepped the USB drive using an existing x86 Linux box (actually, VM, but whatever). I partitioned it (no need to set a bootable partition) and formatted the first partition as ext2 (though since u-Boot doesn't need to read this FS, it could really be any FS you want that the default armedslack kernel supports). I then mounted my new fs, cd'd to it, and rsync'd the armedslack-current tree to it with
rsync --exclude '*/source/*' --delete -Pavv ftp.armedslack.org::armedslack/armedslack-current .
Don't forget that last . at the end!
I plugged in my SD and my USB drive to the Sheeva, fired up my serial terminal, and powered on. I pressed any key to break into the u-Boot bootloader and ran the following commands. Please note that absolutely NO permanent changes are made to u-Boot at this point, so if anything goes wrong, you just powercycle and end up back at the stock Debian Linux install from the internal flash.
setenv arcNumber 2097
setenv mainlineLinux yes
setenv bootargs console=ttyS0,115200 nodhcp kbd=us root=/dev/ram rw
mmcinit
fatload mmc 0:1 0x01100000 /uinitrd-kirkwood-installer
fatload mmc 0:1 0x8000000 uImage-kirkwood
bootm 0x8000000 0x01100000
Once booted into the Slack installer, I simply ran 'setup', selected my target partition as /dev/sda1, then when prompted for a source I selected "pre-mounted" (note: I did NOT pre-mount it! The installer mounts it for you) and entered /mnt/armedslack-current/slackware. The install proceeded normally from this point and I typed 'reboot' when it was complete.
Again, I broke into u-Boot and this time I ran the following, slightly different, commands. Again, NO permanent changes are being made, so the Sheeva will still failsafe to the factory state if you powercycle.
setenv bootargs console=ttyS0,115200 kbd=us root=/dev/sda1 rw
setenv arcNumber 2097
setenv mainlineLinux yes
mmcinit
fatload mmc 0:1 0x01100000 /uinitrd-kirkwood
fatload mmc 0:1 0x8000000 uImage-kirkwood
bootm 0x8000000 0x01100000
Unbelievably, it worked on the first try (well, after an fsck and reboot). Linux boots from the SD, and by the time it gets around to mounting the rootfs off the USB drive, the USB drive is ready to go.
Once I confirmed that everything was working and I was happy with it, I rebooted again, broke into u-Boot again, and this time ran
setenv bootargs console=ttyS0,115200 kbd=us root=/dev/sda1 rw
setenv arcNumber 2097
setenv mainlineLinux yes
setenv bootcmd 'mmcinit; fatload mmc 0:1 0x01100000 /uinitrd-kirkwood; fatload mmc 0:1 0x8000000 uImage-kirkwood; bootm 0x8000000 0x01100000'
saveenv
The 'saveenv' makes these changes permanent, so only do it if you're ready to commit to Slackware. This done, issue a 'reset' or powercycle again and Slackware will get booted from now on.
The first thing that needs to be done to Slack is edit either the rc.ntpd script or rc.local to run 'ntpdate' to set the clock (because there is no RTC clock battery in the Sheeva). I used 0.us.pool.ntp.org, but you should pick an appropriate time server for your situation.
One thing I may consider doing at some point is flashing my kernel and initrd into the Sheeva's internal flash memory so I can remove the SD card. Not at all necessary though.
That's as far as I've gotten. I plan to use this as my MythTV 0.22 backend, so I will post again if/when I make progress on that front.
