Pull power management updates from Rafael Wysocki:
"Once again, cpufreq is the most active development area, mostly
because of the new feature additions and documentation updates in the
amd-pstate driver, but there are also changes in the cpufreq core
related to boost support and other assorted updates elsewhere.
Next up are power capping changes due to the major cleanup of the
Intel RAPL driver.
On the cpuidle front, a new C-states table for Intel Panther Lake is
added to the intel_idle driver, the stopped tick handling in the menu
and teo governors is updated, and there are a couple of cleanups.
Apart from the above, support for Tegra114 is added to devfreq and
there are assorted cleanups of that code, there are also two updates
of the operating performance points (OPP) library, two minor updates
related to hibernation, and cpupower utility man pages updates and
cleanups.
Specifics:
- Update qcom-hw DT bindings to include Eliza hardware (Abel Vesa)
- Update cpufreq-dt-platdev blocklist (Faruque Ansari)
- Minor updates to driver and dt-bindings for Tegra (Thierry Reding,
Rosen Penev)
- Add MAINTAINERS entry for CPPC driver (Viresh Kumar)
- Add support for new features: CPPC performance priority, Dynamic
EPP, Raw EPP, and new unit tests for them to amd-pstate (Gautham
Shenoy, Mario Limonciello)
- Fix sysfs files being present when HW missing and broken/outdated
documentation in the amd-pstate driver (Ninad Naik, Gautham Shenoy)
- Pass the policy to cpufreq_driver->adjust_perf() to avoid using
cpufreq_cpu_get() in the .adjust_perf() callback in amd-pstate
which leads to a scheduling-while-atomic bug (K Prateek Nayak)
- Clean up dead code in Kconfig for cpufreq (Julian Braha)
- Remove max_freq_req update for pre-existing cpufreq policy and add
a boost_freq_req QoS request to save the boost constraint instead
of overwriting the last scaling_max_freq constraint (Pierre
Gondois)
- Embed cpufreq QoS freq_req objects in cpufreq policy so they all
are allocated in one go along with the policy to simplify lifetime
rules and avoid error handling issues (Viresh Kumar)
- Use DMI max speed when CPPC is unavailable in the acpi-cpufreq
scaling driver (Henry Tseng)
- Switch policy_is_shared() in cpufreq to using cpumask_nth() instead
of cpumask_weight() because the former is more efficient (Yury
Norov)
- Use sysfs_emit() in sysfs show functions for cpufreq governor
attributes (Thorsten Blum)
- Update intel_pstate to stop returning an error when "off" is
written to its status sysfs attribute while the driver is already
off (Fabio De Francesco)
- Include current frequency in the debug message printed by
__cpufreq_driver_target() (Pengjie Zhang)
- Refine stopped tick handling in the menu cpuidle governor and
rearrange stopped tick handling in the teo cpuidle governor (Rafael
Wysocki)
- Add Panther Lake C-states table to the intel_idle driver (Artem
Bityutskiy)
- Clean up dead dependencies on CPU_IDLE in Kconfig (Julian Braha)
- Simplify cpuidle_register_device() with guard() (Huisong Li)
- Use performance level if available to distinguish between rates in
OPP debugfs (Manivannan Sadhasivam)
- Fix scoped_guard in dev_pm_opp_xlate_required_opp() (Viresh Kumar)
- Return -ENODATA if the snapshot image is not loaded (Alberto
Garcia)
- Remove inclusion of crypto/hash.h from hibernate_64.c on x86 (Eric
Biggers)
- Clean up and rearrange the intel_rapl power capping driver to make
the respective interface drivers (TPMI, MSR, and MMOI) hold their
own settings and primitives and consolidate PL4 and PMU support
flags into rapl_defaults (Kuppuswamy Sathyanarayanan)
- Correct kernel-doc function parameter names in the power capping
core code (Randy Dunlap)
- Remove unneeded casting for HZ_PER_KHZ in devfreq (Andy Shevchenko)
- Use _visible attribute to replace create/remove_sysfs_files() in
devfreq (Pengjie Zhang)
- Add Tegra114 support to activity monitor device in tegra30-devfreq
as a preparation to upcoming EMC controller support (Svyatoslav
Ryhel)
- Fix mistakes in cpupower man pages, add the boost and epp options
to the cpupower-frequency-info man page, and add the perf-bias
option to the cpupower-info man page (Roberto Ricci)
- Remove unnecessary extern declarations from getopt.h in arguments
parsing functions in cpufreq-set, cpuidle-info, cpuidle-set,
cpupower-info, and cpupower-set utilities (Kaushlendra Kumar)"
* tag 'pm-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (74 commits)
cpufreq/amd-pstate: Add POWER_SUPPLY select for dynamic EPP
cpupower: remove extern declarations in cmd functions
cpuidle: Simplify cpuidle_register_device() with guard()
PM / devfreq: tegra30-devfreq: add support for Tegra114
PM / devfreq: use _visible attribute to replace create/remove_sysfs_files()
PM / devfreq: Remove unneeded casting for HZ_PER_KHZ
MAINTAINERS: amd-pstate: Step down as maintainer, add Prateek as reviewer
cpufreq: Pass the policy to cpufreq_driver->adjust_perf()
cpufreq/amd-pstate: Pass the policy to amd_pstate_update()
cpufreq/amd-pstate-ut: Add a unit test for raw EPP
cpufreq/amd-pstate: Add support for raw EPP writes
cpufreq/amd-pstate: Add support for platform profile class
cpufreq/amd-pstate: add kernel command line to override dynamic epp
cpufreq/amd-pstate: Add dynamic energy performance preference
Documentation: amd-pstate: fix dead links in the reference section
cpufreq/amd-pstate: Cache the max frequency in cpudata
Documentation/amd-pstate: Add documentation for amd_pstate_floor_{freq,count}
Documentation/amd-pstate: List amd_pstate_prefcore_ranking sysfs file
Documentation/amd-pstate: List amd_pstate_hw_prefcore sysfs file
amd-pstate-ut: Add a testcase to validate the visibility of driver attributes
...
On AMD Ryzen Embedded V1780B (Family 17h, Zen 1), the BIOS does not
provide ACPI _CPC objects and the CPU does not support MSR-based CPPC
(X86_FEATURE_CPPC). The _PSS table only lists nominal P-states
(P0 = 3350 MHz), so when get_max_boost_ratio() fails at
cppc_get_perf_caps(), cpuinfo_max_freq reports only the base frequency
instead of the rated boost frequency (3600 MHz).
dmesg:
ACPI CPPC: No CPC descriptor for CPU:0
acpi_cpufreq: CPU0: Unable to get performance capabilities (-19)
cppc-cpufreq already has a DMI fallback (cppc_get_dmi_max_khz()) that
reads the processor max speed from SMBIOS Type 4. Export it and reuse
it in acpi-cpufreq as a last-resort source for the boost frequency.
A sanity check ensures the DMI value is above the _PSS P0 frequency
and within 2x of it; values outside that range are ignored and the
existing arch_set_max_freq_ratio() path is taken instead. The 2x
upper bound is based on a survey of the AMD Ryzen Embedded V1000
series, where the highest boost-to-base ratio is 1.8x (V1404I:
2.0 GHz base / 3.6 GHz boost).
The DMI lookup and sanity check are wrapped in a helper,
acpi_cpufreq_resolve_max_freq(), which falls through to
arch_set_max_freq_ratio() if the DMI value is absent or
out of range.
Tested on AMD Ryzen Embedded V1780B with v7.0-rc4:
Before: cpuinfo_max_freq = 3350000 (base only)
After: cpuinfo_max_freq = 3600000 (includes boost)
Link: https://www.amd.com/en/products/embedded/ryzen/ryzen-v1000-series.html#specifications
Signed-off-by: Henry Tseng <henrytseng@qnap.com>
Link: https://patch.msgid.link/20260324090948.1667340-1-henrytseng@qnap.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently, the `Reference Performance` register is read every time the CPU frequency is sampled in `cppc_get_perf_ctrs()`. This function is on the hot path of the cppc_cpufreq driver. Reference Performance indicates the performance level that corresponds to the Reference Counter incrementing and is not expected to change dynamically during runtime (unlike the Delivered and Reference counters). Reading this register in the hot path incurs unnecessary overhead, particularly on platforms where CPC registers are located in the PCC (Platform Communication Channel) subspace. This patch moves `reference_perf` from the dynamic feedback counters structure (`cppc_perf_fb_ctrs`) to the static capabilities structure (`cppc_perf_caps`). Signed-off-by: Pengjie Zhang <zhangpengjie2@huawei.com> [ rjw: Changelog adjustment ] Link: https://patch.msgid.link/20260213100935.19111-1-zhangpengjie2@huawei.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add sysfs interface to read/write the Performance Limited register.
The Performance Limited register indicates to the OS that an
unpredictable event (like thermal throttling) has limited processor
performance. It contains two sticky bits set by the platform:
- Bit 0 (Desired_Excursion): Set when delivered performance is
constrained below desired performance. Not used when Autonomous
Selection is enabled.
- Bit 1 (Minimum_Excursion): Set when delivered performance is
constrained below minimum performance.
These bits remain set until OSPM explicitly clears them. The write
operation accepts a bitmask of bits to clear:
- Write 0x1 to clear bit 0
- Write 0x2 to clear bit 1
- Write 0x3 to clear both bits
This enables users to detect if platform throttling impacted a workload.
Users clear the register before execution, run the workload, then check
afterward - if set, hardware throttling occurred during that time window.
The interface is exposed as:
/sys/devices/system/cpu/cpuX/cpufreq/perf_limited
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Link: https://patch.msgid.link/20260206142658.72583-7-sumitg@nvidia.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add cppc_get_perf() function to read values of performance control registers including desired_perf, min_perf, max_perf, energy_perf, and auto_sel. This provides a read interface to complement the existing cppc_set_perf() write interface for performance control registers. Note that auto_sel is read by cppc_get_perf() but not written by cppc_set_perf() to avoid unintended mode changes during performance updates. It can be updated with existing dedicated cppc_set_auto_sel() API. Use cppc_get_perf() in cppc_cpufreq_get_cpu_data() to initialize perf_ctrls with current hardware register values during cpufreq policy initialization. Signed-off-by: Sumit Gupta <sumitg@nvidia.com> Reviewed-by: Pierre Gondois <pierre.gondois@arm.com> Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com> Link: https://patch.msgid.link/20260206142658.72583-2-sumitg@nvidia.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull power management updates from Rafael Wysocki:
"By the number of commits, cpufreq is the leading party (again) and the
most visible change there is the removal of the omap-cpufreq driver
that has not been used for a long time (good riddance). There are also
quite a few changes in the cppc_cpufreq driver, mostly related to
fixing its frequency invariance engine in the case when the CPPC
registers used by it are not in PCC. In addition to that, support for
AM62L3 is added to the ti-cpufreq driver and the cpufreq-dt-platdev
list is updated for some platforms. The remaining cpufreq changes are
assorted fixes and cleanups.
Next up is cpuidle and the changes there are dominated by intel_idle
driver updates, mostly related to the new command line facility
allowing users to adjust the list of C-states used by the driver.
There are also a few updates of cpuidle governors, including two menu
governor fixes and some refinements of the teo governor, and a
MAINTAINERS update adding Christian Loehle as a cpuidle reviewer.
[Thanks for stepping up Christian!]
The most significant update related to system suspend and hibernation
is the one to stop freezing the PM runtime workqueue during system PM
transitions which allows some deadlocks to be avoided. There is also a
fix for possible concurrent bit field updates in the core device
suspend code and a few other minor fixes.
Apart from the above, several drivers are updated to discard the
return value of pm_runtime_put() which is going to be converted to a
void function as soon as everybody stops using its return value, PL4
support for Ice Lake is added to the Intel RAPL power capping driver,
and there are assorted cleanups, documentation fixes, and some
cpupower utility improvements.
Specifics:
- Remove the unused omap-cpufreq driver (Andreas Kemnade)
- Optimize error handling code in cpufreq_boost_trigger_state() and
make cpufreq_boost_trigger_state() return -EOPNOTSUPP if no policy
supports boost (Lifeng Zheng)
- Update cpufreq-dt-platdev list for tegra, qcom, TI (Aaron Kling,
Dhruva Gole, and Konrad Dybcio)
- Minor improvements to the cpufreq and cpumask rust implementation
(Alexandre Courbot, Alice Ryhl, Tamir Duberstein, and Yilin Chen)
- Add support for AM62L3 SoC to the ti-cpufreq driver (Dhruva Gole)
- Update arch_freq_scale in the CPPC cpufreq driver's frequency
invariance engine (FIE) in scheduler ticks if the related CPPC
registers are not in PCC (Jie Zhan)
- Assorted minor cleanups and improvements in ARM cpufreq drivers
(Juan Martinez, Felix Gu, Luca Weiss, and Sergey Shtylyov)
- Add generic helpers for sysfs show/store to cppc_cpufreq (Sumit
Gupta)
- Make the scaling_setspeed cpufreq sysfs attribute return the actual
requested frequency to avoid confusion (Pengjie Zhang)
- Simplify the idle CPU time granularity test in the ondemand cpufreq
governor (Frederic Weisbecker)
- Enable asym capacity in intel_pstate only when CPU SMT is not
possible (Yaxiong Tian)
- Update the description of rate_limit_us default value in cpufreq
documentation (Yaxiong Tian)
- Add a command line option to adjust the C-states table in the
intel_idle driver, remove the 'preferred_cstates' module parameter
from it, add C-states validation to it and clean it up (Artem
Bityutskiy)
- Make the menu cpuidle governor always check the time till the
closest timer event when the scheduler tick has been stopped to
prevent it from mistakenly selecting the deepest available idle
state (Rafael Wysocki)
- Update the teo cpuidle governor to avoid making suboptimal
decisions in certain corner cases and generally improve idle state
selection accuracy (Rafael Wysocki)
- Remove an unlikely() annotation on the early-return condition in
menu_select() that leads to branch misprediction 100% of the time
on systems with only 1 idle state enabled, like ARM64 servers
(Breno Leitao)
- Add Christian Loehle to MAINTAINERS as a cpuidle reviewer
(Christian Loehle)
- Stop flagging the PM runtime workqueue as freezable to avoid system
suspend and resume deadlocks in subsystems that assume asynchronous
runtime PM to work during system-wide PM transitions (Rafael
Wysocki)
- Drop redundant NULL pointer checks before acomp_request_free() from
the hibernation code handling image saving (Rafael Wysocki)
- Update wakeup_sources_walk_start() to handle empty lists of wakeup
sources as appropriate (Samuel Wu)
- Make dev_pm_clear_wake_irq() check the power.wakeirq value under
power.lock to avoid race conditions (Gui-Dong Han)
- Avoid bit field races related to power.work_in_progress in the core
device suspend code (Xuewen Yan)
- Make several drivers discard pm_runtime_put() return value in
preparation for converting that function to a void one (Rafael
Wysocki)
- Add PL4 support for Ice Lake to the Intel RAPL power capping driver
(Daniel Tang)
- Replace sprintf() with sysfs_emit() in power capping sysfs show
functions (Sumeet Pawnikar)
- Make dev_pm_opp_get_level() return value match the documentation
after a previous update of the latter (Aleks Todorov)
- Use scoped for each OF child loop in the OPP code (Krzysztof
Kozlowski)
- Fix a bug in an example code snippet and correct typos in the
energy model management documentation (Patrick Little)
- Fix miscellaneous problems in cpupower (Kaushlendra Kumar):
* idle_monitor: Fix incorrect value logged after stop
* Fix inverted APERF capability check
* Use strcspn() to strip trailing newline
* Reset errno before strtoull()
* Show C0 in idle-info dump
- Improve cpupower installation procedure by making the systemd step
optional and allowing users to disable the installation of
systemd's unit file (João Marcos Costa)"
* tag 'pm-6.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (65 commits)
PM: sleep: core: Avoid bit field races related to work_in_progress
PM: sleep: wakeirq: harden dev_pm_clear_wake_irq() against races
cpufreq: Documentation: Update description of rate_limit_us default value
cpufreq: intel_pstate: Enable asym capacity only when CPU SMT is not possible
PM: wakeup: Handle empty list in wakeup_sources_walk_start()
PM: EM: Documentation: Fix bug in example code snippet
Documentation: Fix typos in energy model documentation
cpuidle: governors: teo: Refine intercepts-based idle state lookup
cpuidle: governors: teo: Adjust the classification of wakeup events
cpufreq: ondemand: Simplify idle cputime granularity test
cpufreq: userspace: make scaling_setspeed return the actual requested frequency
PM: hibernate: Drop NULL pointer checks before acomp_request_free()
cpufreq: CPPC: Add generic helpers for sysfs show/store
cpufreq: scmi: Fix device_node reference leak in scmi_cpu_domain_id()
cpufreq: ti-cpufreq: add support for AM62L3 SoC
cpufreq: dt-platdev: Add ti,am62l3 to blocklist
cpufreq/amd-pstate: Add comment explaining nominal_perf usage for performance policy
cpufreq: scmi: correct SCMI explanation
cpufreq: dt-platdev: Block the driver from probing on more QC platforms
rust: cpumask: rename methods of Cpumask for clarity and consistency
...
Update EPP (Energy Performance Preference) constants for more clarity: - Add CPPC_EPP_PERFORMANCE_PREF (0x00) for performance preference. - Rename CPPC_ENERGY_PERF_MAX to CPPC_EPP_ENERGY_EFFICIENCY_PREF (0xFF) for energy efficiency. Signed-off-by: Sumit Gupta <sumitg@nvidia.com> Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com> [ rjw: Changelog edits ] Link: https://patch.msgid.link/20260120145623.2959636-4-sumitg@nvidia.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Remove redundant energy_perf field from 'struct cppc_perf_caps' as the same is available in 'struct cppc_perf_ctrls' which is used. - Move the 'auto_sel' field from 'struct cppc_perf_caps' to 'struct cppc_perf_ctrls' as it represents a control register. Signed-off-by: Sumit Gupta <sumitg@nvidia.com> Reviewed-by: Pierre Gondois <pierre.gondois@arm.com> Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com> Link: https://patch.msgid.link/20260120145623.2959636-3-sumitg@nvidia.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Factor out cppc_perf_ctrs_in_pcc_cpu() for checking whether per-cpu CPC regs are defined in PCC channels, and export it out for further use. Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com> Reviewed-by: Pierre Gondois <pierre.gondois@arm.com> Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com> Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Instead of using CPUFREQ_ETERNAL for signaling an error condition in cppc_get_transition_latency(), change the return value type of that function to int and make it return a proper negative error code on failures. No intentional functional impact. Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org> Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Qais Yousef <qyousef@layalina.io>