[CentOS] powernow-k8 in newer centosplus kernel

Fri Apr 10 05:39:53 UTC 2009
Mark Pryor <tlviewer at yahoo.com>

Hello,

Using kernel:
2.6.18-92.1.13.el5.centos.plus

the cpu throttling works as desired (see 2 traces below)

------------- trace snips --------------
dmesg | grep -i pow
ACPI: SSDT (v001 PTLTD  POWERNOW 0x00000001  LTP 0x00000001) @ 0x3fff9b40
powernow-k8: Found 1 AMD Athlon(tm) 64 X2 Dual Core Processor 4600+ processors (                       2 cpu cores) (version 2.20.00)
powernow-k8:    0 : fid 0x10 (2400 MHz), vid 0x8
powernow-k8:    1 : fid 0xe (2200 MHz), vid 0xa
powernow-k8:    2 : fid 0xc (2000 MHz), vid 0xc
powernow-k8:    3 : fid 0xa (1800 MHz), vid 0xe
powernow-k8:    4 : fid 0x2 (1000 MHz), vid 0x12
ACPI: Power Button (FF) [PWRF]
ACPI: Power Button (CM) [PWRB]

#cpufreq-info
cpufrequtils 002: cpufreq-info (C) Dominik Brodowski 2004-2006
Report errors and bugs to linux at brodo.de, please.
analyzing CPU 0:
  driver: powernow-k8
  CPUs which need to switch frequency at the same time: 0 1
  hardware limits: 1000 MHz - 2.40 GHz
  available frequency steps: 2.40 GHz, 2.20 GHz, 2.00 GHz, 1.80 GHz, 1000 MHz
  available cpufreq governors: ondemand, userspace, performance
  current policy: frequency should be within 1000 MHz and 2.40 GHz.
                  The governor "ondemand" may decide which speed to use
                  within this range.
  current CPU frequency is 1000 MHz (asserted by call to hardware).
(ditto for cpu 1)

------------- end snip ----------

When I update to the newer xx-128.1.6 centosplus kernel all the throttling stops and the box runs at highest speed.

I noticed that the 92* kernel has no separate powernow-k8.ko module, while the 128* kernel does. Does this module now need to be force loaded?

This box is used as a desktop.

-- 
Mark