To check if CPU Frequency scaling is supported, start powersaved and have
a look at: /sys/devices/system/cpu*/cpufreq -> there must
exist files. If you don't find any, but you know your system should support
it, browse/post the mailing list: cpufreq@www.linux.org.uk.
All configuraton variables are described in detail in the
/etc/powersave/cpufreq configuration file.
You may want to override these (or other) variables in the scheme_* files. A scheme and its configuration is activated when switching between AC and battery power source or could be switched by using:
powersave -x (to display available schemes)
powersave -e scheme_name (to switch to a specfic scheme)
You can also use other front-ends like the kpowersave or wmpowersave clients to switch schemes.
You may want to edit existing or create new schemes:
On SUSE systems this can be done by using the YAST power-management module
(recommended) or by modifying the config files (/etc/powersave/scheme_*)
To add an additional scheme by hand, just copy one scheme file and rename it
to scheme_"whatever" (in the same directory). Be sure that you modify the
SCHEME_NAME variable in the file or the powersave daemon will be confused.
Restart the powersaved or send a SIGHUP signal after you modified any config files.
For some specific machines, you need special hacks for loading the cpufreq modules. The ones we know of are listed here, with a description of the chipset, so you can try this out on similar machines. Note that you may need to reboot the machine (or at least unload all cpufreq modules including speedstep_lib and freq_table and after that restart powersaved) to get those working since powersaved does not unload the modules at stop and you need to reload the modules to make those settings effective). Also note that after changing modprobe.conf you need to run "depmod -a" first.
List of machines:
SHARP PC-AR10
=============
lspci excerpt:
0000:00:00.0 Host bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX Host bridge (rev 03)
0000:00:01.0 PCI bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX AGP bridge (rev 03)
/proc/cpuinfo excerpt:
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 8
model name : Pentium III (Coppermine)
stepping : 3
cpu MHz : 647.300
cache size : 256 KB
CPUFREQD_MODULE="speedstep-smi"
CPUFREQD_MODULE_OPTS="smi_sig=1 smi_cmd=0x82 smi_port=0xb2"
COMPAQ ARMADA E500
==================
These are available in different flavours. I have seen one, (with a P III
Coppermine, 800MHz) where adding "options speedstep_lib relaxed_check=1"
to /etc/modprobe.conf.local and setting
CPUFREQD_MODULE="speedstep-smi" was enough to get it going, another
one (P III Coppermine, 700MHz) needs those and additional
CPUFREQD_MODULE_OPTS="smi_cmd=0x82 smi_port=0xb2".
This one has a (lspci):
0000:00:00.0 Host bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX Host bridge (rev 03)
0000:00:01.0 PCI bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX AGP bridge (rev 03)
and (/proc/cpuinfo):
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 8
model name : Pentium III (Coppermine)
stepping : 6
cpu MHz : 697.155
cache size : 256 KB
IBM Thinkpad T20 (model 2647-21G)
=================================
0000:00:00.0 Host bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX Host bridge (rev 03)
0000:00:01.0 PCI bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX AGP bridge (rev 03)
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 8
model name : Pentium III (Coppermine)
stepping : 1
cpu MHz : 647.401
cache size : 256 KB
P III Coppermine, 650MHz, just set CPUFREQD_MODULE="speedstep-smi".