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-rw-r--r--Documentation/ABI/testing/sysfs-devices-system-cpu106
1 files changed, 94 insertions, 12 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 710d47be11e0..ab8cd337f43a 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -111,6 +111,7 @@ What: /sys/devices/system/cpu/cpuidle/available_governors
/sys/devices/system/cpu/cpuidle/current_driver
/sys/devices/system/cpu/cpuidle/current_governor
/sys/devices/system/cpu/cpuidle/current_governer_ro
+ /sys/devices/system/cpu/cpuidle/intel_c1_demotion
Date: September 2007
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description: Discover cpuidle policy and mechanism
@@ -132,7 +133,11 @@ Description: Discover cpuidle policy and mechanism
current_governor_ro: (RO) displays current idle policy.
- See Documentation/admin-guide/pm/cpuidle.rst and
+ intel_c1_demotion: (RW) enables/disables the C1 demotion
+ feature on Intel CPUs.
+
+ See Documentation/admin-guide/pm/cpuidle.rst,
+ Documentation/admin-guide/pm/intel_idle.rst, and
Documentation/driver-api/pm/cpuidle.rst for more information.
@@ -268,6 +273,60 @@ Description: Discover CPUs in the same CPU frequency coordination domain
This file is only present if the acpi-cpufreq or the cppc-cpufreq
drivers are in use.
+What: /sys/devices/system/cpu/cpuX/cpufreq/auto_select
+Date: May 2025
+Contact: linux-pm@vger.kernel.org
+Description: Autonomous selection enable
+
+ Read/write interface to control autonomous selection enable
+ Read returns autonomous selection status:
+ 0: autonomous selection is disabled
+ 1: autonomous selection is enabled
+
+ Write 'y' or '1' or 'on' to enable autonomous selection.
+ Write 'n' or '0' or 'off' to disable autonomous selection.
+
+ This file is only present if the cppc-cpufreq driver is in use.
+
+What: /sys/devices/system/cpu/cpuX/cpufreq/auto_act_window
+Date: May 2025
+Contact: linux-pm@vger.kernel.org
+Description: Autonomous activity window
+
+ This file indicates a moving utilization sensitivity window to
+ the platform's autonomous selection policy.
+
+ Read/write an integer represents autonomous activity window (in
+ microseconds) from/to this file. The max value to write is
+ 1270000000 but the max significand is 127. This means that if 128
+ is written to this file, 127 will be stored. If the value is
+ greater than 130, only the first two digits will be saved as
+ significand.
+
+ Writing a zero value to this file enable the platform to
+ determine an appropriate Activity Window depending on the workload.
+
+ Writing to this file only has meaning when Autonomous Selection is
+ enabled.
+
+ This file is only present if the cppc-cpufreq driver is in use.
+
+What: /sys/devices/system/cpu/cpuX/cpufreq/energy_performance_preference_val
+Date: May 2025
+Contact: linux-pm@vger.kernel.org
+Description: Energy performance preference
+
+ Read/write an 8-bit integer from/to this file. This file
+ represents a range of values from 0 (performance preference) to
+ 0xFF (energy efficiency preference) that influences the rate of
+ performance increase/decrease and the result of the hardware's
+ energy efficiency and performance optimization policies.
+
+ Writing to this file only has meaning when Autonomous Selection is
+ enabled.
+
+ This file is only present if the cppc-cpufreq driver is in use.
+
What: /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1}
Date: August 2008
@@ -423,7 +482,7 @@ What: /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats
/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/occ_reset
Date: March 2016
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
- Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+ Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
Description: POWERNV CPUFreq driver's frequency throttle stats directory and
attributes
@@ -473,7 +532,7 @@ What: /sys/devices/system/cpu/cpufreq/policyX/throttle_stats
/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/occ_reset
Date: March 2016
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
- Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+ Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
Description: POWERNV CPUFreq driver's frequency throttle stats directory and
attributes
@@ -485,6 +544,7 @@ What: /sys/devices/system/cpu/cpuX/regs/
/sys/devices/system/cpu/cpuX/regs/identification/
/sys/devices/system/cpu/cpuX/regs/identification/midr_el1
/sys/devices/system/cpu/cpuX/regs/identification/revidr_el1
+ /sys/devices/system/cpu/cpuX/regs/identification/aidr_el1
/sys/devices/system/cpu/cpuX/regs/identification/smidr_el1
Date: June 2016
Contact: Linux ARM Kernel Mailing list <linux-arm-kernel@lists.infradead.org>
@@ -511,17 +571,20 @@ Description: information about CPUs heterogeneity.
What: /sys/devices/system/cpu/vulnerabilities
/sys/devices/system/cpu/vulnerabilities/gather_data_sampling
+ /sys/devices/system/cpu/vulnerabilities/indirect_target_selection
/sys/devices/system/cpu/vulnerabilities/itlb_multihit
/sys/devices/system/cpu/vulnerabilities/l1tf
/sys/devices/system/cpu/vulnerabilities/mds
/sys/devices/system/cpu/vulnerabilities/meltdown
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
+ /sys/devices/system/cpu/vulnerabilities/old_microcode
/sys/devices/system/cpu/vulnerabilities/reg_file_data_sampling
/sys/devices/system/cpu/vulnerabilities/retbleed
/sys/devices/system/cpu/vulnerabilities/spec_store_bypass
/sys/devices/system/cpu/vulnerabilities/spectre_v1
/sys/devices/system/cpu/vulnerabilities/spectre_v2
/sys/devices/system/cpu/vulnerabilities/srbds
+ /sys/devices/system/cpu/vulnerabilities/tsa
/sys/devices/system/cpu/vulnerabilities/tsx_async_abort
Date: January 2018
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
@@ -562,7 +625,8 @@ Description: Control Symmetric Multi Threading (SMT)
================ =========================================
If control status is "forceoff" or "notsupported" writes
- are rejected.
+ are rejected. Note that enabling SMT on PowerPC skips
+ offline cores.
What: /sys/devices/system/cpu/cpuX/power/energy_perf_bias
Date: March 2019
@@ -605,10 +669,22 @@ Description: Umwait control
Note that a value of zero means there is no limit.
Low order two bits must be zero.
+What: /sys/devices/system/cpu/sev
+ /sys/devices/system/cpu/sev/vmpl
+Date: May 2024
+Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description: Secure Encrypted Virtualization (SEV) information
+
+ This directory is only present when running as an SEV-SNP guest.
+
+ vmpl: Reports the Virtual Machine Privilege Level (VMPL) at which
+ the SEV-SNP guest is running.
+
+
What: /sys/devices/system/cpu/svm
Date: August 2019
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
- Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+ Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
Description: Secure Virtual Machine
If 1, it means the system is using the Protected Execution
@@ -617,7 +693,7 @@ Description: Secure Virtual Machine
What: /sys/devices/system/cpu/cpuX/purr
Date: Apr 2005
-Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Contact: Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
Description: PURR ticks for this CPU since the system boot.
The Processor Utilization Resources Register (PURR) is
@@ -628,7 +704,7 @@ Description: PURR ticks for this CPU since the system boot.
What: /sys/devices/system/cpu/cpuX/spurr
Date: Dec 2006
-Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Contact: Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
Description: SPURR ticks for this CPU since the system boot.
The Scaled Processor Utilization Resources Register
@@ -640,7 +716,7 @@ Description: SPURR ticks for this CPU since the system boot.
What: /sys/devices/system/cpu/cpuX/idle_purr
Date: Apr 2020
-Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Contact: Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
Description: PURR ticks for cpuX when it was idle.
This sysfs interface exposes the number of PURR ticks
@@ -648,7 +724,7 @@ Description: PURR ticks for cpuX when it was idle.
What: /sys/devices/system/cpu/cpuX/idle_spurr
Date: Apr 2020
-Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Contact: Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
Description: SPURR ticks for cpuX when it was idle.
This sysfs interface exposes the number of SPURR ticks
@@ -691,6 +767,12 @@ What: /sys/devices/system/cpu/crash_hotplug
Date: Aug 2023
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description:
- (RO) indicates whether or not the kernel directly supports
- modifying the crash elfcorehdr for CPU hot un/plug and/or
- on/offline changes.
+ (RO) indicates whether or not the kernel updates relevant kexec
+ segments on memory hot un/plug and/or on/offline events, avoiding the
+ need to reload kdump kernel.
+
+What: /sys/devices/system/cpu/enabled
+Date: Nov 2022
+Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
+Description:
+ (RO) the list of CPUs that can be brought online.