setting cpu frequency, and governors

Following files can be used to manipulate cpu frequency
"/sys/devices/system/cpu/cpu0/cpufreq/" .

>cd sys/devices/system/cpu/cpu0/cpufreq/

To set the cpu at maximum frequency ,
>echo performance > scaling_governor
verify it by 
>cat cpuinfo_cur_freq 
it should be 1GHz.

To choose the max and min limit of scaling frequency.
>echo conservative > scaling_governor
>echo maxfreq > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
>echo minfreq  > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
After this cpu will scale the cpu frequency between maxfreq and minfreq.

To force the cpu to run at particular frequency
> echo conservative > scaling_governor
> echo 800000  > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
> echo 800000  > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
 verify it by 
> cat cpuinfo_cur_freq
it should be 800000.

To set the cpu at lowest frequency .
>echo powersave > scaling_governor
verify it by 
>cat cpuinfo_cur_freq
it should be 100000.