Thinkpad X31 ACPI Problems

[Kevin Oberman]

> Date: Sat, 29 Oct 2005 19:05:20 +0200
> From: Kaspar Schleiser <kaspar.schleiser at gmx.de>
> Sender: owner-freebsd-mobile at freebsd.org
> 
> Hello Everybody!
> 
> I installed FreeBSD 6.0-RC1 on my Thinkpad X31. Installation was pretty 
> easy, all the hardware worked out of the box or after loading the right 
> kernel modules.
> 
> Only ACPI is giving me some issues. I spent many hours searching for 
> information, but couldn't solve the problems.
> Perhaps you have some ideas?
> 
> 1. Suspend doesn't turn off the laptop backlight.
> I read something about a patched version of acpi_video that uses DPMS to 
> turn off the screen. Does that work on 6.0-RC1, too?

Your best bet is to get radeontoolport from:
http://www.init-main.com/radeontoolport.tar.gz

Then edit /etc/rc.suspend and /etc/rc.resume to execute it:
radeontool light off
radeontool light on

You might also want to just execute 'radeontool dac off' at boot to turn
off the external video if you don't use it.
> 
> 2. In suspend mode, the system drains a lot of battery and the CPU gets 
> REALLY hot. Nearly burnt the system...
> How can I set up the right CPU throtteling?

Try to get the system to really suspend as far as possible. 
hw.pci.do_power_nodriver: 3
hw.pci.do_power_resume: 1

The former defaults to '0' while the latter defaults to '1'.

Make sure that hw.acpi.cpu.cx_lowest is C3 by placing the following in
/etc/rc.conf:
performance_cx_lowest="LOW"
economy_cx_lowest="LOW"

USB does not suspend well. You may want to remove USB to keep it
off.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634