diff options
| author | Mario Limonciello <mario.limonciello@amd.com> | 2026-05-12 17:19:47 -0500 |
|---|---|---|
| committer | Mario Limonciello (AMD) <superm1@kernel.org> | 2026-05-14 08:47:48 -0500 |
| commit | e4e9b7b38d5db2cc6a8770bc0596bb8b36b92b1f (patch) | |
| tree | f66a2d7dbbdacaf70107c4ef2de1dd8642544780 /Documentation/admin-guide | |
| parent | f9f16835d4dc46113c0a72625ffbf61f1aa95e5c (diff) | |
cpufreq/amd-pstate: Drop Kconfig option for dynamic EPP
There are some performance issues being identified by dynamic EPP
and we don't want to have distributions turning it on by default
exposing them to users at this time.
Drop the kconfig option, and require an explicit opt in from kernel
command line or runtime sysfs option to turn it on.
Reported-by: Viktor Jägersküpper <viktor_jaegerskuepper@freenet.de>
Closes: https://lore.kernel.org/linux-pm/14a87c99-785c-4b16-bfce-35ecbf053448@freenet.de/
Reported-by: Stuart Meckle <stuartmeckle@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221473
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20260512221947.1652988-1-mario.limonciello@amd.com
(fix sysfs file path)
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Diffstat (limited to 'Documentation/admin-guide')
| -rw-r--r-- | Documentation/admin-guide/pm/amd-pstate.rst | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst index f8e7050fc762..a95e2ebce005 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -358,9 +358,9 @@ Dynamic energy performance profile The amd-pstate driver supports dynamically selecting the energy performance profile based on whether the machine is running on AC or DC power. -Whether this behavior is enabled by default depends on the kernel -config option `CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`. This behavior can also be overridden -at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/policyX/dynamic_epp``. +Whether this behavior is enabled by default depends on the kernel command line option +``amd_dynamic_epp`` is set. This behavior can also be overridden +at runtime by the sysfs file ``/sys/devices/system/cpu/amd_pstate/dynamic_epp``. When set to enabled, the driver will select a different energy performance profile when the machine is running on battery or AC power. The driver will @@ -485,9 +485,8 @@ kernel parameter ``amd_prefcore=disable``. ``amd_dynamic_epp`` When AMD pstate is in auto mode, dynamic EPP will control whether the kernel -autonomously changes the EPP mode. The default is configured by -``CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`` but can be explicitly enabled with -``amd_dynamic_epp=enable`` or disabled with ``amd_dynamic_epp=disable``. +autonomously changes the EPP mode. The default is disabled. It can be enabled +with the kernel parameter ``amd_dynamic_epp=enable``. User Space Interface in ``sysfs`` - General =========================================== |