Add documentation for amd_pstate `state` interface. User can see the current state of the driver with the help of this sysfs interface: # cat /sys/devices/system/cpu/amd_pstate/state # disable [passive] guided User can load/unload driver with the help of `state` sysfs interface. - Load driver with passive mode: # echo passive > /sys/devices/system/cpu/amd_pstate/state - Unload the driver: # echo disable > /sys/devices/system/cpu/amd_pstate/state - To switch to guided mode: # echo guided > /sys/devices/system/cpu/amd_pstate/state Signed-off-by: Wyes Karny <wyes.karny@xxxxxxx> --- Documentation/admin-guide/pm/amd-pstate.rst | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst index 06e23538f79c..4d3783516ddc 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -265,6 +265,17 @@ This attribute is read-only. Other performance and frequency values can be read back from ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`. +``state`` + +``amd_pstate`` also exposes a sysfs interface to view and control the driver state. +The driver state can be one of the following: +``disable`` : indicates driver is in unloaded state. +``passive`` : indicates driver is loaded and currently in passive mode. +``guided`` : indicates driver is loaded and currenlty in guided autonomous mode. +This file can be found here: ``/sys/devices/system/cpu/amd_pstate/state``. + +To switch to passive mode: ``echo passive > /sys/devices/system/cpu/amd_pstate/state`` +To switch to guided mode: ``echo guided > /sys/devices/system/cpu/amd_pstate/state`` ``amd-pstate`` vs ``acpi-cpufreq`` ====================================== -- 2.34.1
