ACPI help needed - nearly 50 kernels and still no luck!

optilude

Hey people,

I could really need some insight into the mess that is ACPI. I have a new laptop, an Eveham Voyager Xi 1.6, which is basically a Mitac M3 series with a 1.6GHz centrino, 1Gb RAM, onboard intel sound (i8x0) and graphics (855GM).

Now, I've been trying my luck mostly with various 2.6.0-test6 kernels (currently trying the -mm4 patchset), but the results are invariably the same. I could use some advice on how to get ACPI to work and even just where to look.

The basic problem is that when ACPI is enabled, a process called "events/0" eats 99.9% of my CPU and makes my system almost completely unresponsive. First off - what is events/0? I've tried to google for it, but so far I'm still confused.

I've passed acpi=off on the grub command line to turn ACPI off. Obviously this is not good (still need power management!), but for the time being I thought it would be ok. However, I've discovered that when I pass acpi=off, almost all my devices are left IRQ-less (they all try to be assigned IRQ 0), which means that things like my onboard sound don't work. I also think it affects my onboard graphics, because I can't get the DRI drivers in kernel 2.6.0 to work.

Incidently, if I use a 2.6 series kernel, I shouldn't have to use xfree-drm, should I? emerging xfree-drm fails miserably on missing include files from within the linux sources, so I'm sure it's not 2.6 compatible!

I really need to know - what does ACPI have to do with the allocation of IRQs to my devices? What is events/0 and why is it taking over my CPU when ACPI is enabled? How do I fix this?

I've been thinking it could be a BIOS problem... my BIOS is from AMI and claims to be v02.33, whatever that means. I think my computer came with a windows based flashing tool... where could I find an udated bios? Would it help?

Any help would be greatly appreciated! I've managed to download and compile almost everything I want on my gentoo box now, I just can't configure anything (not alsa, not X, no usb devices ... nothing). The frustration is driving me up the wall!

Best wishes,
Martin
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dook43 · Posted: Thu Oct 09, 2003 3:33 am Post subject:

I was able to get ACPI working without too much of a headache on my (admittedly older) Dell Latitude CPXj (P3-650) system. I basically enabled the support in-kernel and with processor/fan/battery/thermal/button/ac as modules. Kernel 2.6-test5-mm3/4? here.

With all of these modules loaded, I dont have an event/0 process running that takes up that much CPU, although the battery status applet in Gnome takes about 16% (funny, uses up power querying to see how much power is available).

As for your second question, ACPI is used for everything including assigning IRQ's and power management. This is why on a Windows PC you'll see devices using irq's > 15.

You can disable (possibly) ACPI in your bios, although this may not be supported on the centrino platform. Older systems would let you do this and assign IRQ's manually to devices.
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optilude · Posted: Thu Oct 09, 2003 8:43 am Post subject:

Hmm.... had a look in the bios, and I don't think I can disable ACPI.

Does anyone else know what events/0 is and how it is related to ACPI?

Martin
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"Life is both a major and a minor key" -- Travis

nerdbert · l33t Joined: 09 Feb 2003 Posts: 981 Location: Berlin

I guess some of those 50 kernels where from the 2.4 line?
You could put pci=noacpi into grub.conf and see what happens.
Maybe loading the acpi stuff as modules one by one will hint to the culprit.

Updating the BIOS is worth a try. If a new version exists you'll find it on the manufacturer's website. Updating will be a little tricky (because a bootable DOS floppy is usually requiered and I guess your laptop has no floppy drive).

optilude · Posted: Thu Oct 09, 2003 6:43 pm Post subject:

nerdbert · l33t Joined: 09 Feb 2003 Posts: 981 Location: Berlin

curtis119 · Posted: Thu Oct 09, 2003 9:58 pm Post subject:

I had this same problem on an IBM Thinkpad T30. I fixed it by updating the bios. IBM had a linux bios updater for the T30. Yeah IBM!
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Smoke2firE · Posted: Fri Oct 10, 2003 4:26 pm Post subject:

someone mentioned pci=noacpi but did you try acpi=off??

ctford0 · Posted: Fri Oct 10, 2003 4:53 pm Post subject:

Kesereti · Guru Joined: 07 Nov 2002 Posts: 520

Take a look at the output of 'top'...in the 2.6 kernels, the system makes idle calls to the CPU when it's not under load to reduce CPU temperatures -- this makes a lot of CPU usage meters look like the CPU is under constant 100% usage, when really it's just the idling taking up most of it...for example, here's the relevant line from my system at the moment:

optilude · Posted: Sat Oct 11, 2003 10:32 pm Post subject:

I appear to have fixed it now. :-)

The latest patch from acpi.sourceforge.net against the -test7 kernel made all the problems magically disppear! The problem was almost certainly some event in ACPI gone astray (think infinite loop or recursion) that caused keventd (events/0) to eat my CPU. Still testing, but it looks optimistic! :-)

Martin
_________________
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"Life is both a major and a minor key" -- Travis