Kali is a Seagate DockStar (1.2 GHz ARM Feroceon 88FR131, kirkwood) running OpenWrt.
The naming
Kali is the Hindu goddess associated with eternal energy.
She is sometimes depicted with 6 limbs, and the DockStar has 6 connectors (3 USB, 1 Mini-USB, 1 Ethernet, 1 Power). Kālī also means “beyond time”, and the DockStar has no real time clock.
Benchmarks
Power Usage (without USB devices)
- Boot: 3.6 W, Idle: ~2.7 W, Full load: 4.7 W
Ethernet
- iperf: 850 Mbit/sec as client, 786 Mbit/sec as server
Setup
I followed Eric Cooper’s HOWTO, and used his images. I made a backup first as by Alexander Holler.
The only annoying thing is figuring out the IP address of the device. If you don’t want to wait for a /16 nmap ping probe (~15min), it can be easier to quickly set up a local dnsmasq.
DO NOT LET THE DEVICE ACCESS THE INTERNET BEFORE INSTALLING OPENWRT.
Unfortunately, this configuration does not support IPv6, and
due to their own kernel, one cannot use pre-built kmod-ipv6.
I tried building OpenWrt myself, first trunk (25aug2010), then the release Eric used (r22442), which builds but I don’t have the guts to flash it. :|
For now, I’ll wait until OpenWrt is supported officially and stick with the pre-built image for now.
$ opkg install mksh vim-full vim-runtime rsync screen procps --force-overwrite
$ rm /bin/ps
$ ln -s /usr/bin/ps /bin/ps
The fuckup
Too wimpy to just flash my own image, I decided to setup Jeff Doozan’s u-boot with netconsole first, so I could restore the image via TFTP. That was not the best idea, because the thing didn’t boot anymore after that. Damn. (Turns out it expected a debian’s partitioning, not OpenWrt’s.)
Salvation
Time to get a serial connection.
I bought a cheap €3.99 CA-42 Nokia cable on ebay.
It has USB-Id 067b:2303 and needs the module pl2303.
My version has four wires, red, black, green, white and ground on the
shielding. I had to wire GND to the shielding, TX to green, and RX to white.
Red and black are unconnected.
(If you want to do that more professionally, also see yourwarrantyisvoid.com.)
You can access the console with sudo screen /dev/ttyUSB0 115200.
Hopefully you now can restore according to Eric Cooper.
Still, I now have a netconsole, so I can try stuff without the case
open. (Note that Jeff’s u-boot apparently needs $var instead of
$(var) for parameter substitution.)
New horizons
OpenWrt now builds natively from trunk. (09sep2010)
Display
I got a IOGEAR USB 2.0 DisplayLink adapter (Model
GUC2020DW6, USB-Id
17e9:0059) for use with kali. It has native DVI-output as well
as a VGA adapter.
Since OpenWRT didn’t have much of the software I wanted to run, I installed Plugbox—an Arch derivate for ARM—on an USB stick.
The adapter works flawlessy using the kernel module “udlfb” which makes it a framebuffer.
I make it a console with:
openvt -ws -- fbterm -s 10 -n Terminus
The included X.org 1.7.6 works as well. Remember that you need HAL for evdev devices to work.
The third-party xf86-video-displaylink is not noticeably faster than
xf86-video-fbdev, but uses a lot less memory: 21 MB vs ~50 MB.
It works well as a X terminal (e.g. chromium runs fine, and videos up to ~640x480 run smooth, this is a limitation of USB 2.0).
Some terminal benchmarks (100k lines of find-output):
urxvt on kali (xf86-video-fbdev) 4.3s
urxvt on zorya (xf86-video-intel) 0.9s
urxvt on emo (proprietary nvidia) 0.3s
fbterm on kali (displaylink) 68s
fb on zorya (KMS) 67s
fb on emo (uvesafb) 68s
glxgears on kali: 27 FPS at 100% CPU (15% system)
One can also locally run lightweight X11 apps such as mupdf.
Sound
I also got a cheap USB sound card (“Speedlink”, C-Media, USB-Id
0d8c:000c) which works well with snd_usb_audio on OpenWRT. For
Arch Linux, it will have bad noise until you additionally create a
/etc/asound.conf containing:
pcm.!default front
mplayer playing a 128kbit stream needs roughly 25% CPU.