Messages in this thread Patch in this message |  | | From | Perry Yuan <> | Subject | [PATCH v9 13/13] Documentation: amd-pstate: introduce new global sysfs attributes | Date | Mon, 26 Dec 2022 00:34:42 +0800 |
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The amd-pstate driver supports switching working modes at runtime. Users can view and change modes by interacting with the "status" sysfs attribute.
1) check driver mode: $ cat /sys/devices/system/cpu/amd-pstate/status
2) switch mode: `# echo "passive" | sudo tee /sys/devices/system/cpu/amd-pstate/status` or `# echo "active" | sudo tee /sys/devices/system/cpu/amd-pstate/status`
Signed-off-by: Perry Yuan <perry.yuan@amd.com> --- Documentation/admin-guide/pm/amd-pstate.rst | 29 +++++++++++++++++++++ 1 file changed, 29 insertions(+)
diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst index 62744dae3c5f..5f6379475b32 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -339,6 +339,35 @@ processor must provide at least nominal performance requested and go higher if c operating conditions allow. +User Space Interface in ``sysfs`` +================================= + +Global Attributes +----------------- + +``amd-pstate`` exposes several global attributes (files) in ``sysfs`` to +control its functionality at the system level. They are located in the +``/sys/devices/system/cpu/amd-pstate/`` directory and affect all CPUs. + +``status`` + Operation mode of the driver: "active", "passive" or "disable". + + "active" + The driver is functional and in the ``active mode`` + + "passive" + The driver is functional and in the ``passive mode`` + + "disable" + The driver is unregistered and not functional now. + + This attribute can be written to in order to change the driver's + operation mode or to unregister it. The string written to it must be + one of the possible values of it and, if successful, writing one of + these values to the sysfs file will cause the driver to cause the driver + to switch over to the operation mode represented by that string - or to be + unregistered in the "disable" case. + ``cpupower`` tool support for ``amd-pstate`` =============================================== -- 2.34.1
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