kernel/linux.git/Documentation/admin-guide/pm, branch v6.1.178

cpufreq: Documentation: fix conservative governor freq_step description

2026-07-24T13:54:39+00:00

[ Upstream commit 03120e1425262c7d11f93362a88e579a1720390b ] The conservative governor documentation incorrectly states that setting freq_step to 0 will use the default 5% frequency step. In reality, since at least commit 8e677ce83bf4 ("[CPUFREQ] conservative: fixup governor to function more like ondemand logic"), freq_step=0 has always caused the governor to skip frequency updates entirely. Correct the documentation to reflect the actual behavior: freq_step=0 disables frequency changes by the governor entirely. Fixes: 2a0e49279850 ("cpufreq: User/admin documentation update and consolidation") Signed-off-by: Pengjie Zhang Reviewed-by: Zhongqiu Han [ rjw: Subject adjustment ] Link: https://patch.msgid.link/20260603055635.1549943-1-zhangpengjie2@huawei.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

cpufreq: Documentation: fix sampling_down_factor range

2026-07-24T13:54:35+00:00

[ Upstream commit 85524e651d20944399322d46fb97960337831d43 ] The ondemand governor implementation accepts sampling_down_factor values from 1 to 100000 via MAX_SAMPLING_DOWN_FACTOR, but the documentation in admin-guide/pm/cpufreq.rst still says the valid range is 1 to 100. Update the documentation to match the actual code. Fixes: 2a0e49279850 ("cpufreq: User/admin documentation update and consolidation") Reviewed-by: Zhongqiu Han Signed-off-by: Pengjie Zhang Link: https://patch.msgid.link/20260518133457.2408463-1-zhangpengjie2@huawei.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

Documentation: amd-pstate: add driver working mode introduction

2022-11-22T18:57:15+00:00

Introduce the `amd_pstate` driver new working mode with `amd_pstate=passive` added to kernel command line. If there is no passive mode enabled by user, amd_pstate driver will be disabled by default for now. Acked-by: Huang Rui Reviewed-by: Gautham R. Shenoy Tested-by: Wyes Karny Signed-off-by: Perry Yuan Signed-off-by: Rafael J. Wysocki

Documentation: amd-pstate: Add unit test introduction

2022-10-05T17:05:18+00:00

Introduce the AMD P-State unit test module design and implementation. It also talks about kselftest and how to use. Signed-off-by: Meng Li Acked-by: Huang Rui Reviewed-by: Shuah Khan Signed-off-by: Shuah Khan

Merge tag 'x86_cpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2022-08-01T16:49:29+00:00

Pull x86 cpu updates from Borislav Petkov: - Remove the vendor check when selecting MWAIT as the default idle state - Respect idle=nomwait when supplied on the kernel cmdline - Two small cleanups * tag 'x86_cpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Use MSR_IA32_MISC_ENABLE constants x86: Fix comment for X86_FEATURE_ZEN x86: Remove vendor checks from prefer_mwait_c1_over_halt x86: Handle idle=nomwait cmdline properly for x86_idle

x86: Handle idle=nomwait cmdline properly for x86_idle

2022-06-08T19:58:58+00:00

When kernel is booted with idle=nomwait do not use MWAIT as the default idle state. If the user boots the kernel with idle=nomwait, it is a clear direction to not use mwait as the default idle state. However, the current code does not take this into consideration while selecting the default idle state on x86. Fix it by checking for the idle=nomwait boot option in prefer_mwait_c1_over_halt(). Also update the documentation around idle=nomwait appropriately. [ dhansen: tweak commit message ] Signed-off-by: Wyes Karny Signed-off-by: Dave Hansen Tested-by: Zhang Rui Link: https://lkml.kernel.org/r/fdc2dc2d0a1bc21c2f53d989ea2d2ee3ccbc0dbe.1654538381.git-series.wyes.karny@amd.com

Documentation: admin-guide: PM: Add Out of Band mode

2022-05-25T13:48:26+00:00

Update documentation for using the tool to support performance level change via OOB (Out of Band) interface. Signed-off-by: Srinivas Pandruvada Signed-off-by: Rafael J. Wysocki

Merge branch 'pm-docs'

2022-03-29T16:53:28+00:00

Merge additional power management documentation udates for 5.18-rc1: - Add Intel uncore frequency scaling documentation file to its MAINTAINERS entry (Srinivas Pandruvada). - Clean up the AMD P-state driver documentation (Jan Engelhardt). * pm-docs: Documentation: amd-pstate: grammar and sentence structure updates MAINTAINERS: Add additional file to uncore frequency control

Documentation: amd-pstate: grammar and sentence structure updates

2022-03-25T17:29:57+00:00

Signed-off-by: Jan Engelhardt Reviewed-by: Randy Dunlap Signed-off-by: Rafael J. Wysocki

Merge branch 'pm-tools'

2022-03-18T17:46:15+00:00

Merge power management utilities changes for 5.18-rc1: - Add tracer tool for the amd-pstate driver (Jinzhou Su). - Fix PC6 displaying in turbostat on some systems (Artem Bityutskiy). - Add AMD P-State support to the cpupower utility (Huang Rui). * pm-tools: Documentation: amd-pstate: add tracer tool introduction tools/power/x86/amd_pstate_tracer: Add tracer tool for AMD P-state tools/power/x86/intel_pstate_tracer: make tracer as a module cpufreq: amd-pstate: Add more tracepoint for AMD P-State module turbostat: fix PC6 displaying on some systems cpupower: Add "perf" option to print AMD P-State information cpupower: Add function to print AMD P-State performance capabilities cpupower: Move print_speed function into misc helper cpupower: Enable boost state support for AMD P-State module cpupower: Add AMD P-State sysfs definition and access helper cpupower: Introduce ACPI CPPC library cpupower: Add the function to get the sysfs value from specific table cpupower: Initial AMD P-State capability cpupower: Add the function to check AMD P-State enabled cpupower: Add AMD P-State capability flag tools/power/cpupower/{ToDo => TODO}: Rename the todo file tools: cpupower: fix typo in cpupower-idle-set(1) manpage