HOWTO: CPU Frequency Scaling w/ Kernel Module

[ephman]

thanks for the howto! awesome now my machine feels like it should with all the speed i have under the hood. noticed such a huge difference, no lagging now. whew... using the performance option. great stuff.

thanks,
ephman

[Buddha443556]

I'm running a Sempron 2600+ (slot 757), my BIOS settings say that Cool'n'Quiet is enabled, and there's another CPU setting enabled along the lines of 'CPU stepping'. I've removed Powernowd.

AFAIK any (non-mobile) Sempron less than 3000+ does not have Cool'n'Quiet.

Check AMD Athlon™ 64 Processor Power and Thermal Data Sheet [PDF] to be sure. The datasheet for the CPU needs to show at least Min P-State to be a Cool'n'Quiet CPU. The more P-States the better.

[Pootas]

Now this may sound like a n00b question but Im running an AMD64 3200+ on a K7 kernel so under /ect/modules I know I have to put

cpufreq_conservative
cpufreq_ondemand
cpufreq_powersave
cpufreq_stats
cpufreq_userspace
[Module from Step 3]

But how should the last line look ie:

[powernow-k8]
or
powernow-k8

Do you see what I mean....I've done everything else I'm just a bit confused about how the last line should be formatted...

Thanks in advance

[jdong]

Just as an FYI, in Edgy Eft ondemand will be automatically loaded in favor of powernowd by the powernowd startup script, if your CPU can use ondemand without choking (SpeedSteps and other older-generation CPU's had considerable delays on frequency switches, so they will be using powernowd instead)

[pcolamar]

No [], just

powernow-k8

PC

---------------

Now this may sound like a n00b question but Im running an AMD64 3200+ on a K7 kernel so under /ect/modules I know I have to put

cpufreq_conservative
cpufreq_ondemand
cpufreq_powersave
cpufreq_stats
cpufreq_userspace
[Module from Step 3]

But how should the last line look ie:

[powernow-k8]
or
powernow-k8

Do you see what I mean....I've done everything else I'm just a bit confused about how the last line should be formatted...

Thanks in advance

[Pootas]

No [], just

powernow-k8

PC

---------------

I've tried that but my CPU remains at 2.2Ghz....

CPU scaling was working with Powernowd till I changed from a 386 kernel to K7... Maybe there is some issue there but I just cannot get it to work...

[pcolamar]

Well, actually I have got similar problem too.

No matter what I was choosing in Step7, the laptop was always going back to Performance configuration after a while.

Furthermore, I have not be able to find an other GUI to the scaling_governor.

I prefered to go back to powersaved in order to use Kpowersave GUI even if I have the impression that powernow-k8 (my cpu is Turion 64) reacts faster and better in ondemand mode.


I'll check this Thread periodically to see if there is any change

[juve]

Problems: with Athlon XP mobile 2000+ on Desktop-PC (mobo: ECS K7S5A chipset: SiS735)

I get the same errors as some of you:

FATAL: Error inserting powernow_k7 (/lib/modules/2.6.15-26-k7/kernel/arch/i386/kernel/cpu/cpufreq/powernow-k7.ko): No such device

I tried to get proper CPU scaling on FC5 some time ago, but did not succeed.

1. I read somewhere that i had to recompile my kernel with cpufreq support.
2. I read that i had to manually edit the freq_tables because my CPU would not be properly detected

nevertheless, here's some output:

juve@juve:~$ cat /proc/cpuinfo processor       : 0
vendor_id       : AuthenticAMD
cpu family      : 6
model           : 8
model name      : mobile AMD Athlon(tm) XP 2000+
stepping        : 1
cpu MHz         : 1673.940
cache size      : 256 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 1
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow
bogomips        : 3349.70

Does anybody know if it is possible to get cpu-freq support (without kernel recompiling) for my setup

Thx,
Juve

[HAARP]

This could be of interest:
http://www.yggdrasl.demon.co.uk/code/
We need someone to compile the powernow-k7 module with this patch for the Ubuntu kernel. I'm looking into this, but don't expect anything yet.

btw, I don't have the "no such device errors" anymore. Now I get this:

#modprobe powernow-k7; dmesg | tail -n 4
FATAL: Error inserting powernow_k7 (/lib/modules/2.6.15-26-k7/kernel/arch/i386/kernel/cpu/cpufreq/powernow-k7.ko): Unknown symbol in module, or unknown parameter (see dmesg)
[17580497.260000] powernow_k7: disagrees about version of symbol cpu_data
[17580497.260000] powernow_k7: Unknown symbol cpu_data
[17580549.700000] powernow_k7: disagrees about version of symbol cpu_data
[17580549.700000] powernow_k7: Unknown symbol cpu_data

edit: Should've rebooted after kernel update.

# modprobe powernow_k7; dmesg | tail -n 7
FATAL: Error inserting powernow_k7 (/lib/modules/2.6.15-26-k7/kernel/arch/i386/kernel/cpu/cpufreq/powernow-k7.ko): No such device
[17179674.576000] powernow: PowerNOW! Technology present. Can scale: frequency and voltage.
[17179674.580000] powernow: No PST tables match this cpuid (0x7a0)
[17179674.580000] powernow: This is indicative of a broken BIOS.
[17179674.580000] powernow: Trying ACPI perflib
[17179674.580000] powernow: ACPI perflib can not be used in this platform
[17179674.580000] powernow: ACPI and legacy methods failed
[17179674.580000] powernow: See http://www.codemonkey.org.uk/projects/cpufreq/powernow-k7.shtml

[pharcyde]

I believe a lot of you are having problems because the bios does not have a processor state table available. If that is the case, then the kernel modules will not work.

There are a few options.

1) Try to get an updated bios with support with ptable support for your cpu.

2) Recompiling the kernel as suggested by others. Look at the following links.

http://www.yggdrasl.demon.co.uk/code/ (Provided by HAARP)
http://wejp.k.vu/projects/howto_cnq_athlon_64_x2/ (At the bottom of the howto instructions)