Firmware Test Suite - maxfreq test

This test checks the maximum CPU frequency as detected by the kernel for each CPU against maximum frequency as specified by the BIOS frequency scaling settings. It has been known for firmware to incorrectly set the maximum frequency scaling setting below the maximum CPU frequency which results in a machine that cannot run at full speed. The test also ensures that all CPUs are configured consistently with respect to the maximum allowed frequency.


fwts maxfreq - 

..runs the test on your machine and dumps the output to stdout.

Explanation of test results

Certain test results may require a little more explanation. This section will try and give some context to specific test failures.

Error ID



Could not open /sys/devices/system/cpu for the given CPUs on the machine.


Could not read /sys/devices/system/cpu/cpuX/cpufreq/scaling_available_frequencies.


The maximum available scaling frequency does not match that available on the CPU which means that there is a firmware configuration error, for example the ACPI _PSS object is mis-configured (see section _PSS (Performance Supported States) of the ACPI specification).

FirmwareTestSuite/Reference/maxfreq (last edited 2016-01-11 07:25:38 by anthonywong)