I think you can do it with a single command. Something like this:

http://www.linuxquestions.org/questi...85#post2692385

Hi Brian,

I have used the cpufreq kernel option over several kernel versions. My setup is doubtless slightly different from yours, but I have had great success with ondemand. Using gkrellm (simple plugin required) I can see the processor speed (and cpu temp) varing according to load.

I also have a k8 processor, but the chipset is via not nforce2.

here are the kernel option that i use:



#
# CPU Frequency scaling
#
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_TABLE=y
# CONFIG_CPU_FREQ_DEBUG is not set
CONFIG_CPU_FREQ_STAT=m
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=y
CONFIG_CPU_FREQ_GOV_USERSPACE=y
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
# CONFIG_CPU_FREQ_GOV_CONSERVATIVE is not set

#
# CPUFreq processor drivers
#
CONFIG_X86_ACPI_CPUFREQ=m
# CONFIG_X86_POWERNOW_K6 is not set
# CONFIG_X86_POWERNOW_K7 is not set
CONFIG_X86_POWERNOW_K8=y
# CONFIG_X86_GX_SUSPMOD is not set
# CONFIG_X86_SPEEDSTEP_CENTRINO is not set
# CONFIG_X86_SPEEDSTEP_ICH is not set
# CONFIG_X86_SPEEDSTEP_SMI is not set
# CONFIG_X86_P4_CLOCKMOD is not set
# CONFIG_X86_CPUFREQ_NFORCE2 is not set
# CONFIG_X86_LONGRUN is not set
# CONFIG_X86_LONGHAUL is not set

#
# shared options
#
# CONFIG_X86_ACPI_CPUFREQ_PROC_INTF is not set
# CONFIG_X86_SPEEDSTEP_LIB is not set


i guess the option
# CONFIG_X86_CPUFREQ_NFORCE2

would maybe be set to yes in your case.


as you can see i elected to compile the options in, as opposed to modules.


then, in /etc/rc.d/rc.local, I add

echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

and thats it, it just works

I didn't need to reset the processor speed steps, it just worked 'out of the box'
~$ dmesg | grep powernow
powernow-k8: Found 1 AMD Athlon(tm) 64 Processor 3500+ processors (version 2.00.00)
powernow-k8: 0 : fid 0x2 (1000 MHz), vid 0x12
powernow-k8: 1 : fid 0xa (1800 MHz), vid 0xa
powernow-k8: 2 : fid 0xc (2000 MHz), vid 0x6
powernow-k8: 3 : fid 0xe (2200 MHz), vid 0x2
~$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
2200000
~$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies
1000000 1800000 2000000 2200000

maybe there is something useful for you in that lot?

tobyl

Well, I managed to get it working by making "performance" be the default governor. Now I can switch between all available frequencies. It doesn't seem like I should have had to do this, though. This must either be a bug or something wrong with my hardware, because it always showed 2G as an available frequency, but I could not use it.

Tobyl,

I have been using the conservative governor instead of the ondemand governor because I read that the AMD64 don't work well with the fast scaling of the ondemand governor. It sounds like you don't have any problem with it, though?

Brian

Not at all. My AMD64 3500 behaves very well. It ticks over at 1000MHz most of the time, but as soon as I give it some work to do, it ramps up the MHz rapidly. There is an asus utility that does the same in windows, (forgotten the name as I so rarely boot into windows), but the effect is identical.
I had not heard that AMD64 was not good with ondemand. I have got 1 gig of high quality ram, maybe that helps?

Anyway, glad you got it working...

tobyl

More on this:

It seems that the max frequency depends on whether the laptop is plugged in or not. Normally my machine should have 3 available freqs, .8, 1.6 and 2. If the machine is unplugged, the max I can do is 1.6. If I plug it back in I have 2 available again. (That's why I thought I had a bad cpu, because sometimes 2 would be available and sometimes not.)

Despite the original thread subject, this is _not_ specific to any kernel version.

Brian