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2025-07-16Documentation: amd-pstate:fix minimum performance state label errorshouyeliu
In the AMD P-States Performance Scale diagram, the labels for "Max Perf" and "Lowest Perf" were incorrectly used to define the range for "Desired Perf".The "Desired performance target" should be bounded by the "Maximum requested performance" and the "Minimum requested performance", which corresponds to "Max Perf" and "Min Perf", respectively. Signed-off-by: Shouye Liu <shouyeliu@tencent.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Link: https://lore.kernel.org/r/20250522070140.17557-1-shouyeliu@gmail.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-12-10cpufreq/amd-pstate: Store the boost numerator as highest perf againMario Limonciello
commit ad4caad58d91d ("cpufreq: amd-pstate: Merge amd_pstate_highest_perf_set() into amd_get_boost_ratio_numerator()") changed the semantics for highest perf and commit 18d9b52271213 ("cpufreq/amd-pstate: Use nominal perf for limits when boost is disabled") worked around those semantic changes. This however is a confusing result and furthermore makes it awkward to change frequency limits and boost due to the scaling differences. Restore the boost numerator to highest perf again. Suggested-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Fixes: ad4caad58d91 ("cpufreq: amd-pstate: Merge amd_pstate_highest_perf_set() into amd_get_boost_ratio_numerator()") Link: https://lore.kernel.org/r/20241209185248.16301-2-mario.limonciello@amd.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-09-11amd-pstate: Add missing documentation for `amd_pstate_prefcore_ranking`Mario Limonciello
`amd_pstate_prefcore_ranking` reflects the dynamic rankings of a CPU core based on platform conditions. Explicitly include it in the documentation. Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-09-11cpufreq: amd-pstate: Add documentation for `amd_pstate_hw_prefcore`Mario Limonciello
Explain that the sysfs file represents both preferred core being enabled by the user and supported by the hardware. Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-09-11cpufreq: amd-pstate: Merge amd_pstate_highest_perf_set() into ↵Mario Limonciello
amd_get_boost_ratio_numerator() The special case in amd_pstate_highest_perf_set() is the value used for calculating the boost numerator. Merge this into amd_get_boost_ratio_numerator() and then use that to calculate boost ratio. This allows dropping more special casing of the highest perf value. Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-06-26Documentation: cpufreq: amd-pstate: update doc for Per CPU boost control methodPerry Yuan
Updates the documentation in `amd-pstate.rst` to include information about the per CPU boost control feature. Users can now enable or disable the Core Performance Boost (CPB) feature on individual CPUs using the `boost` sysfs attribute. Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Perry Yuan <perry.yuan@amd.com> Co-developed-by: Mario Limonciello <mario.limonciello@amd.com> Link: https://lore.kernel.org/r/20240626042733.3747-5-mario.limonciello@amd.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-06-20Documentation: PM: amd-pstate: add guided mode to the Operation modePerry Yuan
the guided mode is also supported, so the operation mode should include that mode as well. Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Perry Yuan <perry.yuan@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Link: https://lore.kernel.org/r/a61d825ef71f6aacc8f1624fe9fb982b8446b5a7.1718811234.git.perry.yuan@amd.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2024-02-12Documentation: PM: amd-pstate: Fix section title underlineMeng Li
Title under line too short Signed-off-by: Meng Li <li.meng@amd.com> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-01-31Documentation: amd-pstate: introduce amd-pstate preferred coreMeng Li
Introduce amd-pstate preferred core. check preferred core state set by the kernel parameter: $ cat /sys/devices/system/cpu/amd-pstate/prefcore Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Perry Yuan <perry.yuan@amd.com> Signed-off-by: Meng Li <li.meng@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-01-10Documentation: admin-guide: PM: Fix two typosErwan Velu
Fix two typos in the admin-guide: - a missing e in "reference_perf" in cppc_sysfs.rst. - the amd_pstate sysfs path uses a dash instead of an underscore. Signed-off-by: Erwan Velu <e.velu@criteo.com> [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-03-17Documentation: cpufreq: amd-pstate: Update amd_pstate status sysfs for guidedWyes Karny
Update amd_pstate status sysfs for guided mode. Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-22Merge tag 'docs-6.3' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a moderately calm cycle for documentation; the significant changes include: - Some significant additions to the memory-management documentation - Some improvements to navigation in the HTML-rendered docs - More Spanish and Chinese translations ... and the usual set of typo fixes and such" * tag 'docs-6.3' of git://git.lwn.net/linux: (68 commits) Documentation/watchdog/hpwdt: Fix Format Documentation/watchdog/hpwdt: Fix Reference Documentation: core-api: padata: correct spelling docs/mm: Physical Memory: correct spelling in reference to CONFIG_PAGE_EXTENSION docs: Use HTML comments for the kernel-toc SPDX line docs: Add more information to the HTML sidebar Documentation: KVM: Update AMD memory encryption link printk: Document that CONFIG_BOOT_PRINTK_DELAY required for boot_delay= Documentation: userspace-api: correct spelling Documentation: sparc: correct spelling Documentation: driver-api: correct spelling Documentation: admin-guide: correct spelling docs: add workload-tracing document to admin-guide docs/admin-guide/mm: remove useless markup docs/mm: remove useless markup docs/mm: Physical Memory: remove useless markup docs/sp_SP: Add process magic-number translation docs: ftrace: always use canonical ftrace path Doc/damon: fix the data path error dma-buf: Add "dma-buf" to title of documentation ...
2023-02-15Documentation: amd-pstate: disambiguate user space sectionsBagas Sanjaya
kernel test robot reported htmldocs warning: Documentation/admin-guide/pm/amd-pstate.rst:343: WARNING: duplicate label admin-guide/pm/amd-pstate:user space interface in ``sysfs``, other instance in Documentation/admin-guide/pm/amd-pstate.rst The documentation contains two sections with the same "User Space Interface in ``sysfs``" title. The first one deals with per-policy sysfs and the second one is about general attributes (currently only global attributes are documented). Disambiguate title text of both sections to fix the warning. Link: https://lore.kernel.org/linux-doc/202302151041.0SWs1RHK-lkp@intel.com/ Fixes: b9e6a2d47b2565 ("Documentation: amd-pstate: introduce new global sysfs attributes") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Acked-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-03Documentation: amd-pstate: introduce new global sysfs attributesPerry Yuan
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` Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <perry.yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-03Documentation: amd-pstate: add amd pstate driver mode introductionPerry Yuan
The amd-pstate driver has two operation modes supported: * CPPC Autonomous (active) mode * CPPC non-autonomous (passive) mode. active mode and passive mode can be chosen by different kernel parameters. Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-03Documentation: amd-pstate: add EPP profiles introductionPerry Yuan
The amd-pstate driver supports a feature called energy performance preference (EPP). Add information to the documentation to explain how users can interact with the sysfs files for this feature. 1) See all EPP profiles $ sudo cat /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_available_preferences default performance balance_performance balance_power power 2) Check current EPP profile $ sudo cat /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_preference performance 3) Set new EPP profile $ sudo bash -c "echo power > /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_preference" Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-02-02Documentation: admin-guide: correct spellingRandy Dunlap
Correct spelling problems for Documentation/admin-guide/ as reported by codespell. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan.x@bytedance.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: cgroups@vger.kernel.org Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@kernel.org> Cc: dm-devel@redhat.com Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: linux-media@vger.kernel.org Cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230129231053.20863-2-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-12-12Merge tag 'linux-kselftest-next-6.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kselftest updates from Shuah Khan: "Several fixes and enhancements to existing tests and a few new tests: - add new amd-pstate tests and fix and enhance existing ones - add new watchdog tests and enhance existing ones to improve coverage - fixes to ftrace, splice_read, rtc, and efivars tests - fixes to handle egrep obsolescence in the latest grep release - miscellaneous spelling and SPDX fixes" * tag 'linux-kselftest-next-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (24 commits) selftests/ftrace: Use long for synthetic event probe test selftests/tpm2: Split async tests call to separate shell script runner selftests: splice_read: Fix sysfs read cases selftests: ftrace: Use "grep -E" instead of "egrep" selftests: gpio: Use "grep -E" instead of "egrep" selftests: kselftest_deps: Use "grep -E" instead of "egrep" selftests/efivarfs: Add checking of the test return value cpufreq: amd-pstate: fix spdxcheck warnings for amd-pstate-ut.c selftests: rtc: skip when RTC is not present selftests/ftrace: event_triggers: wait longer for test_event_enable selftests/vDSO: Add riscv getcpu & gettimeofday test Documentation: amd-pstate: Add tbench and gitsource test introduction selftests: amd-pstate: Trigger gitsource benchmark and test cpus selftests: amd-pstate: Trigger tbench benchmark and test cpus selftests: amd-pstate: Split basic.sh into run.sh and basic.sh. selftests: amd-pstate: Rename amd-pstate-ut.sh to basic.sh. selftests/ftrace: Convert tracer tests to use 'requires' to specify program dependency selftests/ftrace: Add check for ping command for trigger tests selftests/watchdog: Fix spelling mistake "Temeprature" -> "Temperature" selftests/watchdog: add test for WDIOC_GETTEMP ...
2022-11-22Documentation: amd-pstate: add driver working mode introductionPerry Yuan
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 <ray.huang@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Tested-by: Wyes Karny <wyes.karny@amd.com> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-11-01Documentation: amd-pstate: Add tbench and gitsource test introductionMeng Li
Introduce tbench and gitsource test cases design and implementation. Monitor cpus changes about performance and power consumption etc. Signed-off-by: Meng Li <li.meng@amd.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-05Documentation: amd-pstate: Add unit test introductionMeng Li
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 <li.meng@amd.com> Acked-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-03-29Merge branch 'pm-docs'Rafael J. Wysocki
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
2022-03-25Documentation: amd-pstate: grammar and sentence structure updatesJan Engelhardt
Signed-off-by: Jan Engelhardt <jengelh@inai.de> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-09Documentation: amd-pstate: add tracer tool introductionJinzhou Su
Add amd pstate tracer tool introduction Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com> Reviewed-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-30Documentation: amd-pstate: Add AMD P-State driver introductionHuang Rui
Introduce the AMD P-State driver design and implementation. Signed-off-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>