Downclock when idle

[wonderiuy]

Hi all, long time crawler but first message here.

My question is: are these commands supported in config.txt?
arm_freq_min
core_freq_min
sdram_freq_min
over_voltage_min

They should work only on overclocked RPI and are used to specify the frequency of clocks when system go idle or with low cpu load. I've added them to config.txt but they doesn't seem to work (or it seems that they are never triggered).

I've added also the line
force_turbo=0
and disabled initial_turbo
but with no success.

All commands can be found here: http://elinux.org/RPi_config.txt#Overclocking_options
Since i'm not a Linux expert, do you have any suggestions?
Thank you in advance

[CurlyMo]

Doesn't work on XBian because it was made to force the system to run on a stable clock w/o loosing warranty.

[wonderiuy]

This sounds very very strange because that value are meant for DOWNclocking. Never heard that downclocking leads to loose the warranty.
You are speaking of xbian overclocking, i'm speaking of downclocking.
Is there any particular settings to do for making that commands work?

[mk01]

@wonderiuy

edit /etc/default/xbian-module-init-tools uncomment CPUFREQ_GOVERNOR and set it to "ondemand".

btw: as far as I know SDRAM freq NEVER changes dynamically.

[f1vefour]

You may have to adjust the up_threshold of the ondemand governor or it spins up too easily, I think you also must change the minimum frequency. The min and max values used to both be the same max value.

[mk01]

@f1vefour

arm_freq_min is by default set to 700. arm_freq is by default the same value. by changing arm_freq to higher number arm_freq_min is not changed.
frequencies is not changing FW but kernel alone. and if arm_clock is not going back to arm_freq_min is caused only by performance governor which is active by default. changing it to ondemand (or powersave) allows the clock to go down to arm_freq_min.

arm_freq_min can be set also to lower value from default 700. and again arm will lower the freq only if governor is changed.
(just a wrap-up that there is no confusion of any kind)