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Posts: 946 | Thanked: 1,650 times | Joined on Oct 2009 @ Germany
ok, let me give you a mini-tutorial (the scripts are so powerful that a full description woiuld take a lot of time to write):

Note: this refers to kernel-power-flasher >= v27 and kernel-power-settings >= 0.8 from

in theory, if you install the new version the old settings should still work and be loaded during boot.
(kernel-config = sudo /usr/sbin/kernel-config, here abbreviated)

 kernel-config show
shows you the current configuration of the kernel.

If you have loaded an old config, or changed the current settings manually or using ClockfreqUI you can save the current settings with
kernel-config save myconfig
this will automatically save it in /home/user/.kernel/myconfig
and create the directory if necessary (replace myconfig with any name you like).
To save it somewhere else (why would you?) use the absolute path.

 kernel-config load myconfig
loads the configuration. if the filename is not absolute (e.g. "./myconfig") it searches
for the file in the current dir, /home/user/.kernel and /usr/share/kernel-power-settings/
Without a file name it loads /etc/default/kernel-power, or /usr/share/kernel-power-settings/default
Do NOT modify the files in /usr/share/kernel-power-settings. They are templates.
The template names are: default, lv, ulv, xlv, ideal.

 kernel-config default myconfig
copies the configuration file to /etc/default/kernel-power (or symlinks if it is a template file from /usr/share/kernel-power-settings). If you do not specify a filename, the current settings are saved in /etc/default/kernel-power.
These settings are then loaded during boot.

 kernel-config limits 250 600
sets the limits to [min,max].
If you use "-" for a frequency, the current value is used. For example, "kernel-config limits - 850" only changes the upper limit to 850Mhz.

kernel-config lock freq volt dsp
(e.g. 500 48 400)
can be used to test voltage and dsp settings with a certain frequency.
it overwrites the current settings for that frequency and locks the CPU
to only that frequency until you run "kernel-config unlock" to unlock it.

The boot sequence:
the kernel settings are only loaded if you had a normal reboot or shutdown
but not after a crash. In that case the file /etc/kernel-power/.notloaded is created
and a GUI app could notify you and ask whether to load the settings again.
The settings will be loaded at the next boot again unless it crashes again.

you can edit the files in /home/user/.kernel/.
here is the content of the default template:
# minimum frequency to use
# maximum frequency to use
# list of frequency configurations: each "frequency:volt,dsprate"
FREQS="0:30,90 125:30,90 250:38,180 500:48,360 550:54,400 600:60,430 700:60,430 750:60,430 805:60,430 850:60,500 900:60,500 950:60,500 1000:60,500 1100:72,520 1150:72,520"
there is a separate file /etc/defaul/kernel-boot for boot options.
these two options are highly experimental and may brick your device!
# start USB networking and sshd early during boot
# fsck of /home partition before mounting?
# 1=if necessary, force=always check
operations before mounting /home:
if you have a script (e.g. for repartitiong) called /etc/kernel-power/pre-mount.once
it will be executed once and then moved away.
with FSCK_HOME enabled the /home partition (first ext3 on eMMC) will be fsck on boot.
echo 1 > /etc/kernel-power/force_fsck
should check it only during next boot.
echo 0 > /etc/kernel-power/force_fsck
disables it only for the next boot.
if you reset or reboot the device during fsck, it will not fsck (only) during the next boot.
all messages are logged to /etc/kernel-power/pre-mount.log
If you know how one could show a fancy LED animation from the shell during fsck contact me.

Last edited by titan; 2010-05-13 at 09:37. Reason: booting, pre-mount, templates, v0.6, versions

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