Dynamically control cpu clock freq. and vcore with Powernowd on the Zaurus!
Here's the patch for Powernowd 0.96 which enables controlling clock and vcore on pxa270-based Z's under Linux. It should work on all pxa270-based Z's running 2.4.20 kernel with the following cpu/voltage changing patches:
including ones running 2.4 kernel-based pdaXrom and cacko's distributions. For impatient and those who can't compile, there's a pre-compiled package available here.
A word of caution: it's possible to permanently damage hardware when running outside of manufacturer's set specifications.
That said, my Zaurus SL-C1000 runs just fine at much lower voltage than specified by Intel. Here's a copy of my /etc/powernowd.conf file.
Here's a patch for XFCE 22.214.171.124 systemload panel plugin for Linux that corrects the cpu load graph scaling on the Zaurii (actually, it accounts for kapm-idled kernel thread cpu time) and also shows the current cpu freq and vcore voltage. To enable displaying freq/vcore, mark checkbox next to "Text to display" for CPU monitor in systemload plugin settings dialog. Please notice that displaying freq/vcore will put quite a load on the system itself (it would add approx. 15% of system time @ default 416MHz), so it's probably not a good idea to have it enabled outside of debug/testing environment. I think that's because of slow access to i2c (lots of delay loops) in Sharp's kernel.
Credits: Some code/ideas are borrowed from busybox and Piro's qclockchange.
You can reach me at albertr at iral dot com.