APM resume problem with 5.2R on IBM T30

[Kevin Oberman]

> From: "Jake Khuon" <khuon at NEEBU.Net>
> Date: Sun, 18 Jan 2004 02:24:04 -0800
> Sender: owner-freebsd-mobile at freebsd.org
> 
> Running 5.2-RELEASE on an IBM ThinkPad T30 (2366-81U)...
> 
> When I come back from APM suspend, my machine will display a "Resetting ATA"
> (or something to that effect) and then promptly hang while constantly
> spinning the hard drive.  Anyone else seeing this?  Also, I apologise if I
> missed it but anyone know if ACPI support works for this platform yet?
> 
> Oh... and as a warning for all you folks running prior to 5.2 who might have
> /stuck a symlink for usr/libexec to /libexec in order to get OpenOffice
> /working... remove it before attempting an upgrade.  Or maybe I'm the only
> bozo that did that. |8^)

Jake,

I recently switched over to ACPI on my T30 because many problems that
were making it unattractive have been resolved. Most notably, the
problem you are seeing was seen only with ACPI in most cases and was
just fixed in CURRENT. Unfortunately, I believe the fix was too late to
make 5.2. If you don't want to run CURRENT, which I've been running for
well over a year on my T30 (2366-92U), you might at least grab
everything in /usr/src/sys/dev/ata/ and replace the ATA/ATAPI drivers in
your RELEASE system with those in CURRENT.

As far as ACPI goes, ALMOST everything works including CPU throttling
and "deeper sleep" modes on P4-M and Centrino CPUs. You can really
stretch battery life with these, but they are not "automatic" yet. You
need to manually set them when switching to battery or AC., although I
know Nate was planning on adding the code to make the switch
automatically in the near future. The required changes have already
been made to default/rc.conf.

The one big problem I see is that my display backlight does not turn off
when I suspend. In fact, if I turn the backlight off with the lid-switch
before suspending, it turns on when I suspend and the lid switch no
longer works! Also, the display does not blank. It simply freezes and
"rots" as the divers are no longer powered. It does return from suspend
fine.

In general I find ACPI to be a better choice than APM for my T30, but te
cost is not being able to really suspend. I get much better performance
on battery with ACPI than APM. An added win is the ability to read the
CPU temperature properly. gkrellm2 temperature now works correctly with
ACPI. I suspect that ACPI will be really ready for prime-time in about 3
months, depending on how much free time Nate and the other doing work on
ACPI support have available.
-- 
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