[PATCH v13 8/9] Documentation: cpufreq: amd-pstate: introduce the new cpu boost control method

From: Perry Yuan
Date: Fri Jun 21 2024 - 12:53:49 EST


From: Perry Yuan <Perry.Yuan@xxxxxxx>

Introduce AMD CPU frequency boosting control sysfs entry which used for
switching boost on and boost off.

If core performance boost is disabled while a core is in a boosted P-state,
the core automatically transitions to the highest performance non-boosted P-state
The highest perf and frequency will be limited by the setting value.

Signed-off-by: Perry Yuan <Perry.Yuan@xxxxxxx>
Reviewed-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
Documentation/admin-guide/pm/amd-pstate.rst | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index f5ee81419a93..dc1b10d7dd09 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -440,6 +440,23 @@ control its functionality at the system level. They are located in the
This attribute is read-only to check the state of preferred core set
by the kernel parameter.

+``cpb_boost``
+ Specifies whether core performance boost is requested to be enabled or disabled
+ If core performance boost is disabled while a core is in a boosted P-state, the
+ core automatically transitions to the highest performance non-boosted P-state.
+ AMD Core Performance Boost(CPB) is controlled by this attribute file which allows
+ user to change all cores frequency boosting state. It supports all amd-pstate modes.
+
+ States of the driver "/sys/devices/system/cpu/amd_pstate/cpb_boost"
+ "disabled" Core Performance Boosting Disabled.
+ "enabled" Core Performance Boosting Enabled.
+
+ To enable core performance boost:
+ # echo "enabled" > /sys/devices/system/cpu/amd_pstate/cpb_boost
+
+ To disable core performance boost:
+ # echo "disabled" > /sys/devices/system/cpu/amd_pstate/cpb_boost
+
``cpupower`` tool support for ``amd-pstate``
===============================================

--
2.34.1