Couldn't find the cpufreq folder of Linux on ZYBO

[Tseng]

I have successfully boot the Embedded Linux of Digilen-linux-Dev according to Embedded_Linux_Hands-on_Tutorial.pdf.

Now I want to simulate the DVFS using Linux's CPUFreq framework,so I managed to look up the Frequency Table and OPP list.But I didn't find the folder called "cpufreq" which might be located at "/sys/device/system/cpu/cpu0/cpufreq".

Where should I find this folder,because I want to know what  frequency/voltage set I can use to vary before I simulate DVFS operation.

[JColvin]

Hi Tseng,

I personally don't know the answer, but I asked some of our applications engineers to see if they happen to know.

Thanks,
JColvin

[sbobrowicz]

I'm not familiar with this framework in linux, but I think this page may help you:

http://www.wiki.xilinx.com/Zynq+Power+Management

Ensure all the kernel config options specified there are enabled using menuconfig before building the kernel. You may also need to enable the PM_DEVFREQ option and some associated with it. Last thing I will mention is to make sure your devicetree has the bindings as described in the site above.