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→Diva Frequency Scaling
== Diva Frequency Scaling ==
The frequency of the CPU can be changed on the run using the Cpufreq framework. The cpufreq framework works in conjunction with the related driver & governor.
Cpufreq implementation controls the Linux OPP (Operating Performance Points) adjusting the Cortex-A8 core voltages and frequencies.
To view the supported OPP's (frequency in KHz)
<pre>
target# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies
275000 500000 600000 720000
target#
</pre>
To view the supported OPP's (frequency in KHz),
<pre>
target# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies
275000 500000 600000 720000
target#
</pre>
To change the OPP,
<pre>
target# echo 275000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed
target#
</pre>
Please note that OPP can be changed only using the userspace governor. If governors like ondemand is used, OPP change happens automatically based on the system load.
For further details, please refer to the [http://processors.wiki.ti.com/index.php/AM335x_Linux_Power_Management_User_Guide AM335x Linux Power Management User Guide].
= Application notes =