# Clocksource unstable with 2.6.22 [solved]

## Braempje

I'm trying the tickless kernel feature in 2.6.22, in order to save power. Booting this does not work: my system hangs, after a declaration that the clocksource is unstable and "a possible TSC halt in C2". I have a Pentium M with working frequency scaling, this caused bugs before 2.6.22 but that should be solved. Adding clocksource=acpi_pm to grub does not solve the problem, unlike other reports. This is my grub.conf entry:

```
title  Gentoo Linux 2.6.22

root (hd0,5)

kernel /boot/kernel-gentoo-2.6.22 root=/dev/sda8 clocksource=acpi_pm
```

Any ideas would be very welcome, I'd love to use this feature.

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## micmac

Try 2.6.22.5 (latest) and also compile in support for HPET clocksource (remove clocksource=acpi_pm from your boot cmd line) and high res timers. Check your BIOS for HPET activation.

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## Braempje

 *micmac wrote:*   

> Try 2.6.22.5 (latest) and also compile in support for HPET clocksource (remove clocksource=acpi_pm from your boot cmd line) and high res timers. Check your BIOS for HPET activation.

 I have support for HPET and high res timers enabled in the latest gentoo-sources kernel. I'll remove the clocksource line from my boot command line and check my BIOS settings, I'm not sure if HPET is activated. But that's for the next reboot   :Wink: 

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## tobimat80

I'm using 2.6.22.5 and hpet/ high res timer is compiled in. But I'm suffering the same problem. My boot time is delayed around 1 minute  :Sad: 

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## Braempje

 *Braempje wrote:*   

>  *micmac wrote:*   Try 2.6.22.5 (latest) and also compile in support for HPET clocksource (remove clocksource=acpi_pm from your boot cmd line) and high res timers. Check your BIOS for HPET activation. I have support for HPET and high res timers enabled in the latest gentoo-sources kernel. I'll remove the clocksource line from my boot command line and check my BIOS settings, I'm not sure if HPET is activated. But that's for the next reboot  

 I could not find anything related to HPET in my BIOS settings (on a Dell Inspiron 9300). Rebooting without the kernel command line gave the same problem. My kernel config, with commented lines stripped out, can be seen at http://pastebin.com/m6c389703, perhaps this helps to solve this strange problem?

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## tobimat80

Ok. This sounds strange to me, but I compiled the ipw2200-driver as a module and the delay time is gone... Hm, hope that helps

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## Braempje

 *tobimat80 wrote:*   

> Ok. This sounds strange to me, but I compiled the ipw2200-driver as a module and the delay time is gone... Hm, hope that helps

 That fixed it, very strange but it works. Thanks!

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## nagmat84

Same problem here.

After I installed ipw2200 as a module the delay was gone. Actually the delay never was caused by an unstable clock source, but by the ipw2200 driver. The ipw2200 was unable to load the firmware and waited until a timeout occurred. (Accidently the "tsc" message was the last message before the ipw2200 driver.)

The new question is, why does the ipw2200 driver fails to load the firmware? The firmware is successfully loaded by my old 2.6.20-r8 kernel. My new 2.6.22-r9 refuses to load the firmware. But this is actually another topic.

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