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phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Wed 27. Jan 2010, 13:14
by stansfield
Hi, I am using karmic koala with the Linux 2.6.31.17-phc-Kernel from over here: https://launchpad.net/~linux-phc/+archive/ppa and PHCTool2-pre-3. It's a notebook with a 1,5 Ghz-Core2Duo. I have set values via the tool which are displayed in the tool after reboot, but I have two Problems:

1. How can I check wether or not my new voltage values are active?
2. How comes there are no phc...-files here:

Code: Select all

p@p-laptop:~$ ls /sys/devices/system/cpu/cpu0/cpufreq/
affected_cpus               related_cpus                   scaling_max_freq
cpuinfo_cur_freq            scaling_available_frequencies  scaling_min_freq
cpuinfo_max_freq            scaling_available_governors    scaling_setspeed
cpuinfo_min_freq            scaling_cur_freq               stats
cpuinfo_transition_latency  scaling_driver
ondemand                    scaling_governor
I hope my post isn't too noobish...

Re: phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Wed 27. Jan 2010, 16:53
by the-fallen
Your question is not noobish, not for us.

As I understand you installed the ppa kernel and phctool (not maintained!).

You also need to install the phc modules for your CPU.
The Kernel package does not include them, it is just prepared to use phc modules in ubuntu.

Re: phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Thu 28. Jan 2010, 11:21
by kubunteando
I have exactly the same problem.
I have installed the kernel from the ppa in Kubuntu Karmic and I have compiled the phc-k8 0.4.2 version.
I can see that phc-k8 loads by checking the output of "dmesg" but I behaves the same way as powernow_k8.

I cannot see the phc files en /sys/devices/system/cpu/cpu0/cpufreq/

I use an AMD Athlon II 605e (desktop quad core), and I thought it is supported in phc-k8 0.4.2?

Re: phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Thu 28. Jan 2010, 12:39
by stansfield
It seems to work now. I have installed the script and I have written a little config file. Now /sys/devices/system/cpu/cpu1/cpufreq/phc_controls gives the right values. The PC seems to be a lot quieter, too. Is there any other way to verify if everything works as intended?

Thanks for the help.

Re: phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Thu 28. Jan 2010, 20:34
by the-fallen
@ stansfield

Good to read that you made it and that you already see/hear/feel some improvements.
To see if the values you put in the config file are really applied to the CPU you can use the tool "read_msr" available in the download section. Using that tool you can verify the applied settings for the current speed. If you manually iterate each speed on your computer and check the values you can see if everything is okay.

Also comparing the power usage with and without undervolting may give you some data - even if they are not exact and you need to make sure that similar circumstances are available for both testing series. (maybe you run a 100% cpu-eating programm each time).
You can use intels "powertop" - utility to measure power consumption while your laptop runs on battery.

@ kubunteando

I do not really know what AMD - CPUs are supported and which one are not. Maybe the AMD developer will see this thread soon but he is somewhat busy at the time. Maybe you can find some information in this forum. There are some scattered around because others already asked that question. Maybe you find something matching your CPU.
If not please open a new threat with a more matching topic (but "AMD" in it) so if can be found easier if the AMD developer snoops around again.

Re: phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Fri 29. Jan 2010, 12:52
by DavidG
kubunteando wrote:I have exactly the same problem.
I have installed the kernel from the ppa in Kubuntu Karmic and I have compiled the phc-k8 0.4.2 version.
I can see that phc-k8 loads by checking the output of "dmesg" but I behaves the same way as powernow_k8.

I cannot see the phc files en /sys/devices/system/cpu/cpu0/cpufreq/

I use an AMD Athlon II 605e (desktop quad core), and I thought it is supported in phc-k8 0.4.2?
Unfortunately the AMD Athlon II is a AMD family 10h processor and thus not yet supported. I am working on it, but I just started a new job and I am rather busy at the moment...
All I can say is check this forum regularly...

Re: phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Fri 29. Jan 2010, 23:37
by kubunteando
Thanks, I watch regularly these forums.

If I can help anyway let me know.

Re: phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Sun 21. Feb 2010, 10:52
by stansfield
Can I use the intel-phc-patch only on ***-phc-Kernels or on all Kernels (i.e. the new 2.6.31-20 for Ubuntu)?

Re: phc-files missing in /sys/devices/system/cpu/cpu0/cpufreq/

Posted: Sun 21. Feb 2010, 15:18
by the-fallen
In theory you can use it on any kernel you'd like to.
But the Ubuntu default kernel for example has the cpufreq-drivers compiled-in, not as a module so you can not replace it.

Thats why we have the ppa with ubuntu kernels. They are like the default ones but the cpufreq drivers are compiled as module and can be replaced easily.