MX6 serial port command line operation of CPU clock speed, mx6 serial port

MX6 serial port command line operation of CPU clock speed, mx6 serial port

When using imx6 for project development, you may need to check the clock speed of imx6 or set the clock speed of imx6. The following describes how to operate the imx6 frequency on the serial port command line in the system:

CPU directory:

Root @ sabresd_6dq:/sys/devices/system/cpu/cpu0/cpufreq # ls
Affected_cpus
Cpuinfo_cur_freq
Cpuinfo_max_freq
Cpuinfo_min_freq
Cpuinfo_transition_latency
Related_cpus
Scaling_available_frequencies
Scaling_available_governors
Scaling_cur_freq
Scaling_driver
Scaling_governor
Scaling_max_freq
Scaling_min_freq
Scaling_setspeed
Stats

(1) view the current CPU frequency:

Cat cpuinfo_cur_freq

(2) view the minimum clock speed

Catcpuinfo_min_freq

(3) view the maximum clock speed

Catcpuinfo_max_freq

(5) view CPU supported clock speed

Catscaling_available_frequencies

(4) set the clock speed (unit: KH, for example, 792 Mhz, 792000 should be used)

Echo 792000> scaling_setspeed

(5) query the working modes supported by CPU

Catscaling_available_governors

Working modes: interactive conservative ondemand userspace powersave performance

Performance. The maximum frequency is used, regardless of power consumption. High-performance mode, run at the best frequency you set
Interactive. Go directly to the highest frequency, and then check that the CPU load is slowly decreasing.
Powersave. It is usually run at the lowest frequency, and the smoothness will be affected. It is generally not used! Low-load operation at a set minimum frequency, saving power but slow system response speed
Userspace. You can manually adjust the frequency in the user space.

As the CPU load increases, conservative gradually increases the frequency to the highest, and then drops to the lowest
Ondemand. Check the load regularly and adjust the Frequency Based on the load. The system overclock mode, which is automatically adjusted between the maximum and minimum frequencies

Supplement: after testing, we found that using echo 792000> scaling_setspeed directly cannot modify the I. mx6 clock speed. At this time, the CPU mode is Interactive, and you need to change the mode to Userspace. Command Execution sequence:

Echo userspace> scaling_governor

Echo 792000> scaling_setspeed

In this way, the clock speed can be modified successfully.