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2024-03-27Documentation: PM: Update platform_pci_wakeup_init() referenceBjorn Helgaas1-1/+1
platform_pci_wakeup_init() was removed by d2e5f0c16ad6 ("ACPI / PCI: Rework the setup and cleanup of device wakeup") but was still mentioned in the documentation. Update the doc to refer to pci_acpi_setup(), which does the equivalent work. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Dhruva Gole <d-gole@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-03-13Documentation: power: Fix typo in suspend and interrupts docSaravana Kannan1-1/+1
Typos are bad. Fix them. Signed-off-by: Saravana Kannan <saravanak@google.com> Reviewed-by: Dhruva Gole <d-gole@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-03-11Merge branch 'pm-em'Rafael J. Wysocki1-4/+179
Merge Enery Model changes for 6.9-rc1: - Allow the Energy Model to be updated dynamically (Lukasz Luba). * pm-em: (24 commits) PM: EM: Fix nr_states warnings in static checks Documentation: EM: Update with runtime modification design PM: EM: Add em_dev_compute_costs() PM: EM: Remove old table PM: EM: Change debugfs configuration to use runtime EM table data drivers/thermal/devfreq_cooling: Use new Energy Model interface drivers/thermal/cpufreq_cooling: Use new Energy Model interface powercap/dtpm_devfreq: Use new Energy Model interface to get table powercap/dtpm_cpu: Use new Energy Model interface to get table PM: EM: Optimize em_cpu_energy() and remove division PM: EM: Support late CPUs booting and capacity adjustment PM: EM: Add performance field to struct em_perf_state and optimize PM: EM: Add em_perf_state_from_pd() to get performance states table PM: EM: Introduce em_dev_update_perf_domain() for EM updates PM: EM: Add functions for memory allocations for new EM tables PM: EM: Use runtime modified EM for CPUs energy estimation in EAS PM: EM: Introduce runtime modifiable table PM: EM: Split the allocation and initialization of the EM table PM: EM: Check if the get_cost() callback is present in em_compute_costs() PM: EM: Introduce em_compute_costs() ...
2024-03-11Merge branch 'pm-cpufreq'Rafael J. Wysocki1-1/+1
Merge cpufreq changes for 6.9-rc1: - Enable preferred core support in the amd-pstate cpufreq driver (Meng Li). - Fix min_perf assignment in amd_pstate_adjust_perf() and make the min/max limit perf values in amd-pstate always stay within the (highest perf, lowest perf) range (Tor Vic, Meng Li). - Change default transition delay in cpufreq to 2ms (Qais Yousef). - Drop long-unused cpudata::prev_cummulative_iowait from the intel_pstate cpufreq driver (Jiri Slaby). - Allow intel_pstate to assign model-specific values to strings used in the EPP sysfs interface and make it do so on Meteor Lake (Srinivas Pandruvada). - Remove references to 10ms minimum sampling rate from comments in the cpufreq code (Pierre Gondois). - Prevent scaling_cur_freq from exceeding scaling_max_freq when the latter is an inefficient frequency (Shivnandan Kumar). - Honour transition_latency over transition_delay_us in cpufreq (Qais Yousef). - Stop unregistering cpufreq cooling on CPU hot-remove (Viresh Kumar). - General enhancements / cleanups to ARM cpufreq drivers (tianyu2, Nícolas F. R. A. Prado, Erick Archer, Arnd Bergmann, Anastasia Belova). - Update cpufreq-dt-platdev to block/approve devices (Richard Acayan). - Make the SCMI cpufreq driver get a transition delay value from firmware (Pierre Gondois). * pm-cpufreq: (28 commits) cpufreq: scmi: Set transition_delay_us firmware: arm_scmi: Populate fast channel rate_limit firmware: arm_scmi: Populate perf commands rate_limit cpufreq: Don't unregister cpufreq cooling on CPU hotplug cpufreq: Honour transition_latency over transition_delay_us cpufreq: Limit resolving a frequency to policy min/max cpufreq: amd-pstate: adjust min/max limit perf cpufreq: Remove references to 10ms min sampling rate cpufreq: intel_pstate: Update default EPPs for Meteor Lake cpufreq: intel_pstate: Allow model specific EPPs cpufreq: qcom-hw: add CONFIG_COMMON_CLK dependency cpufreq: dt-platdev: block SDM670 in cpufreq-dt-platdev cpufreq: intel_pstate: remove cpudata::prev_cummulative_iowait cpufreq: Change default transition delay to 2ms cpufreq: amd-pstate: Fix min_perf assignment in amd_pstate_adjust_perf() Documentation: PM: amd-pstate: Fix section title underline Documentation: introduce amd-pstate preferrd core mode kernel command line options Documentation: amd-pstate: introduce amd-pstate preferred core cpufreq: amd-pstate: Update amd-pstate preferred core ranking dynamically ACPI: cpufreq: Add highest perf change notification ...
2024-03-11Merge branch 'pm-runtime'Rafael J. Wysocki1-9/+14
Merge changes related to the runtime power management of devices for 6.9-rc1: - Simplify pm_runtime_get_if_active() usage and add a replacement for pm_runtime_put_autosuspend() (Sakari Ailus). - Add a tracepoint for runtime_status changes tracking (Vilas Bhat). - Fix section title markdown in the runtime PM documentation (Yiwei Lin). * pm-runtime: Documentation: PM: Fix runtime_pm.rst markdown syntax PM: runtime: add tracepoint for runtime_status changes PM: runtime: Add pm_runtime_put_autosuspend() replacement PM: runtime: Simplify pm_runtime_get_if_active() usage
2024-02-29Documentation: PM: Fix runtime_pm.rst markdown syntaxYiwei Lin1-0/+1
The '7. Generic subsystem callbacks' should be a section title, but the markdown syntax is not adequate now. Fix it so the chapter can be linked at docs.kernel.org correctly. Signed-off-by: Yiwei Lin <s921975628@gmail.com> [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-02-12Documentation: PM: Fix PCI hibernation support descriptionRinHizakura1-1/+1
According to the context, 'pci_pm_suspend_noirq' is the right word for the changed sentence. Signed-off-by: Yiwei Lin <s921975628@gmail.com> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-02-12PM: runtime: Add pm_runtime_put_autosuspend() replacementSakari Ailus1-6/+11
Add __pm_runtime_put_autosuspend() that replaces pm_runtime_put_autosuspend() for new users. The intent is to later re-purpose pm_runtime_put_autosuspend() to also mark the device's last busy stamp---which is what the vast majority of users actually need. This is also described in pm_runtime_put_autosuspend() documentation. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-02-12PM: runtime: Simplify pm_runtime_get_if_active() usageSakari Ailus1-3/+2
There are two ways to opportunistically increment a device's runtime PM usage count, calling either pm_runtime_get_if_active() or pm_runtime_get_if_in_use(). The former has an argument to tell whether to ignore the usage count or not, and the latter simply calls the former with ign_usage_count set to false. The other users that want to ignore the usage_count will have to explicitly set that argument to true which is a bit cumbersome. To make this function more practical to use, remove the ign_usage_count argument from the function. The main implementation is in a static function called pm_runtime_get_conditional() and implementations of pm_runtime_get_if_active() and pm_runtime_get_if_in_use() are moved to runtime.c. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Alex Elder <elder@linaro.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Takashi Iwai <tiwai@suse.de> # sound/ Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com> # drivers/accel/ivpu/ Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com> # drivers/gpu/drm/i915/ Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> # drivers/pci/ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-02-08Documentation: EM: Update with runtime modification designLukasz Luba1-4/+179
Add a new description which covers the information about runtime EM. It contains the design decisions, describes models and how they reflect the reality. Remove description of the default EM. Add example driver code which modifies EM. Add API documentation for the new feature which allows to modify the EM in runtime. Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-01-23Documentation: power: Use kcalloc() instead of kzalloc()Erick Archer1-1/+1
As noted in the "Deprecated Interfaces, Language Features, Attributes, and Conventions" documentation [1], size calculations (especially multiplication) should not be performed in memory allocator (or similar) function arguments due to the risk of them overflowing. This could lead to values wrapping around and a smaller allocation being made than the caller was expecting. Using those allocations could lead to linear overflows of heap memory and other misbehaviors. So, in the example code use the purpose specific kcalloc() function instead of the argument size * count in the kzalloc() function. At the same time, modify the translations accordingly. Signed-off-by: Erick Archer <erick.archer@gmx.com> Reviewed-by: Hu Haowen <2023002089@link.tyut.edu.cn> Reviewed-by: Yanteng Si <siyanteng@loongson.cn> Reviewed-by: Hu Haowen <2023002089@link.tyut.edu.cn> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2023-12-19Documentation: PM: Adjust freezing-of-tasks.rst to the freezer changesKevin Hao1-37/+48
The core freezer logic has been modified by commit f5d39b020809 ("freezer,sched: Rewrite core freezer logic"), so adjust the documentation to reflect the new code. The main changes include: - Drop references to PF_FROZEN and PF_FREEZER_SKIP - Describe TASK_FROZEN, TASK_FREEZABLE and __TASK_FREEZABLE_UNSAFE - Replace system_freezing_cnt with freezer_active - Use a different example for the loop of a freezable kernel thread, since the old code is gone gone Signed-off-by: Kevin Hao <haokexin@gmail.com> [ rjw: Subject and changelog edits, doc text adjustments ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-08-18Documentation: Fix typosBjorn Helgaas1-2/+2
Fix typos in Documentation. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-04-27regulator: consumer.rst: fix 'regulator_enable' typo.Philippe De Muyter1-1/+1
Removing an erroneous 'd' at the end of 'regulator_enable'. Signed-off-by: Philippe De Muyter <phdm@macqel.be> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/1682537582-2314-1-git-send-email-Philippe.DeMuyter@macq.eu Signed-off-by: Mark Brown <broonie@kernel.org>
2023-02-21Merge tag 'pm-6.3-rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add EPP support to the AMD P-state cpufreq driver, add support for new platforms to the Intel RAPL power capping driver, intel_idle and the Qualcomm cpufreq driver, enable thermal cooling for Tegra194, drop the custom cpufreq driver for loongson1 that is not necessary any more (and the corresponding cpufreq platform device), fix assorted issues and clean up code. Specifics: - Add EPP support to the AMD P-state cpufreq driver (Perry Yuan, Wyes Karny, Arnd Bergmann, Bagas Sanjaya) - Drop the custom cpufreq driver for loongson1 that is not necessary any more and the corresponding cpufreq platform device (Keguang Zhang) - Remove "select SRCU" from system sleep, cpufreq and OPP Kconfig entries (Paul E. McKenney) - Enable thermal cooling for Tegra194 (Yi-Wei Wang) - Register module device table and add missing compatibles for cpufreq-qcom-hw (Nícolas F. R. A. Prado, Abel Vesa and Luca Weiss) - Various dt binding updates for qcom-cpufreq-nvmem and opp-v2-kryo-cpu (Christian Marangi) - Make kobj_type structure in the cpufreq core constant (Thomas Weißschuh) - Make cpufreq_unregister_driver() return void (Uwe Kleine-König) - Make the TEO cpuidle governor check CPU utilization in order to refine idle state selection (Kajetan Puchalski) - Make Kconfig select the haltpoll cpuidle governor when the haltpoll cpuidle driver is selected and replace a default_idle() call in that driver with arch_cpu_idle() to allow MWAIT to be used (Li RongQing) - Add Emerald Rapids Xeon support to the intel_idle driver (Artem Bityutskiy) - Add ARCH_SUSPEND_POSSIBLE dependencies for ARMv4 cpuidle drivers to avoid randconfig build failures (Arnd Bergmann) - Make kobj_type structures used in the cpuidle sysfs interface constant (Thomas Weißschuh) - Make the cpuidle driver registration code update microsecond values of idle state parameters in accordance with their nanosecond values if they are provided (Rafael Wysocki) - Make the PSCI cpuidle driver prevent topology CPUs from being suspended on PREEMPT_RT (Krzysztof Kozlowski) - Document that pm_runtime_force_suspend() cannot be used with DPM_FLAG_SMART_SUSPEND (Richard Fitzgerald) - Add EXPORT macros for exporting PM functions from drivers (Richard Fitzgerald) - Remove /** from non-kernel-doc comments in hibernation code (Randy Dunlap) - Fix possible name leak in powercap_register_zone() (Yang Yingliang) - Add Meteor Lake and Emerald Rapids support to the intel_rapl power capping driver (Zhang Rui) - Modify the idle_inject power capping facility to support 100% idle injection (Srinivas Pandruvada) - Fix large time windows handling in the intel_rapl power capping driver (Zhang Rui) - Fix memory leaks with using debugfs_lookup() in the generic PM domains and Energy Model code (Greg Kroah-Hartman) - Add missing 'cache-unified' property in the example for kryo OPP bindings (Rob Herring) - Fix error checking in opp_migrate_dentry() (Qi Zheng) - Let qcom,opp-fuse-level be a 2-long array for qcom SoCs (Konrad Dybcio) - Modify some power management utilities to use the canonical ftrace path (Ross Zwisler) - Correct spelling problems for Documentation/power/ as reported by codespell (Randy Dunlap)" * tag 'pm-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (53 commits) Documentation: amd-pstate: disambiguate user space sections cpufreq: amd-pstate: Fix invalid write to MSR_AMD_CPPC_REQ dt-bindings: opp: opp-v2-kryo-cpu: enlarge opp-supported-hw maximum dt-bindings: cpufreq: qcom-cpufreq-nvmem: make cpr bindings optional dt-bindings: cpufreq: qcom-cpufreq-nvmem: specify supported opp tables PM: Add EXPORT macros for exporting PM functions cpuidle: psci: Do not suspend topology CPUs on PREEMPT_RT MIPS: loongson32: Drop obsolete cpufreq platform device powercap: intel_rapl: Fix handling for large time window cpuidle: driver: Update microsecond values of state parameters as needed cpuidle: sysfs: make kobj_type structures constant cpuidle: add ARCH_SUSPEND_POSSIBLE dependencies PM: EM: fix memory leak with using debugfs_lookup() PM: domains: fix memory leak with using debugfs_lookup() cpufreq: Make kobj_type structure constant cpufreq: davinci: Fix clk use after free cpufreq: amd-pstate: avoid uninitialized variable use cpufreq: Make cpufreq_unregister_driver() return void OPP: fix error checking in opp_migrate_dentry() dt-bindings: cpufreq: cpufreq-qcom-hw: Add SM8550 compatible ...
2023-02-01power: remove pda_power supply driverArnd Bergmann1-2/+2
This driver was used for a couple of Intel PXA and Samsung S3C24xx based PDAs, but all of those are now removed from the kernel, so the driver itself is no longer useful. Cc: Anton Vorontsov <cbou@mail.ru> Cc: linux-pm@vger.kernel.org Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-01-30Documentation: power: correct spellingRandy Dunlap1-1/+1
Correct spelling problems for Documentation/power/ as reported by codespell. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-29Merge branches 'pm-devfreq', 'pm-qos', 'pm-tools' and 'pm-docs'Rafael J. Wysocki1-1/+1
Merge devfreq changes, PM QoS change, and power management tools and documentation changes for v5.20-rc1: - Add new devfreq driver for Mediatek CCI (Cache Coherent Interconnect) (Johnson Wang). - Convert the Samsung Exynos SoC Bus bindings to DT schema of exynos-bus.c (Krzysztof Kozlowski). - Address kernel-doc warnings by adding the description for unused fucntion parameters in devfreq core (Mauro Carvalho Chehab). - Use NULL to pass a null pointer rather than zero according to the function propotype in imx-bus.c (Colin Ian King). - Print error message instead of error interger value in tegra30-devfreq.c (Dmitry Osipenko). - Add checks to prevent setting negative frequency QoS limits for CPUs (Shivnandan Kumar). - Update the pm-graph suite of utilities to the latest revision 5.9 including multiple improvements (Todd Brandt). - Drop pme_interrupt reference from the PCI power management documentation (Mario Limonciello). * pm-devfreq: PM / devfreq: tegra30: Add error message for devm_devfreq_add_device() PM / devfreq: imx-bus: use NULL to pass a null pointer rather than zero PM / devfreq: shut up kernel-doc warnings dt-bindings: interconnect: samsung,exynos-bus: convert to dtschema PM / devfreq: mediatek: Introduce MediaTek CCI devfreq driver dt-bindings: interconnect: Add MediaTek CCI dt-bindings * pm-qos: PM: QoS: Add check to make sure CPU freq is non-negative * pm-tools: pm-graph v5.9 * pm-docs: Documentation: PM: Drop pme_interrupt reference
2022-07-15Documentation: EM: Switch to micro-Watts scaleLukasz Luba1-7/+7
The EM now uses the micro-Watts scale for the power values. Update related documentation to reflect that fact. Fix also a problematic sentence in the doc "to:" which triggers test scripts complaining about wrong email address. Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-08Documentation: PM: Drop pme_interrupt referenceMario Limonciello1-1/+1
`pme_interrupt` was dropped from `struct pci_dev` as part of commit 8370c2dc4c7b ("PCI / PM: Drop pme_interrupt flag from struct pci_dev"), but the Documentation still includes this member. Remove it from the documentation as well and update it to have the missing `pme_poll` member instead. Fixes: 8370c2dc4c7b ("PCI / PM: Drop pme_interrupt flag from struct pci_dev") Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13Documentation: EM: Add artificial EM registration descriptionLukasz Luba1-0/+20
Add description about new artificial EM registration and use cases. Update also the documentation with the new .get_cost() callback description and usage. Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13PM: EM: Change the order of arguments in the .active_power() callbackLukasz Luba1-2/+2
The .active_power() callback passes the device pointer when it's called. Aligned with a convetion present in other subsystems and pass the 'dev' as a first argument. It looks more cleaner. Adjust all affected drivers which implement that API callback. Suggested-by: Ionela Voinescu <ionela.voinescu@arm.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-03Documentation: EM: Describe new registration method using DTLukasz Luba1-0/+10
The new registration method allows to get power values from the DT OPP definition. The new OPP entry property "opp-microwatt" contains total power expressed in micro-Watts. Align the EM documentation with this new possible registration method of EM. Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-01-10Merge branches 'pm-opp', 'pm-devfreq' and 'powercap'Rafael J. Wysocki1-7/+7
Merge an operating performance points (OPP) update, devfreq updates and power capping updates for 5.17-rc1: - Update outdated OPP documentation (Tang Yizhou). - Reduce log severity for informative message regarding frequency transition failures in devfreq (Tzung-Bi Shih). - Add DRAM frequency controller devfreq driver for Allwinner sunXi SoCs (Samuel Holland). - Add missing COMMON_CLK dependency to the sun8i devfreq driver (Arnd Bergmann). - Add support for new layout of Psys PowerLimit Register on SPR to the Intel RAPL power capping driver (Zhang Rui). - Fix typo in a comment in idle_inject.c (Jason Wang). - Remove unused function definition from the DTPM (Dynamit Thermal Power Management) power capping framework (Daniel Lezcano). - Reduce DTPM trace verbosity (Daniel Lezcano). * pm-opp: Documentation: power: Update outdated contents in opp.rst * pm-devfreq: PM / devfreq: Reduce log severity for informative message PM / devfreq: sun8i: addd COMMON_CLK dependency PM / devfreq: Add a driver for the sun8i/sun50i MBUS * powercap: powercap/drivers/dtpm: Reduce trace verbosity powercap/drivers/dtpm: Remove unused function definition powercap: fix typo in a comment in idle_inject.c powercap: intel_rapl: support new layout of Psys PowerLimit Register on SPR
2021-12-30Merge branch 'opp/linux-next' of ↵Rafael J. Wysocki1-7/+7
git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm Pull OPP (operating performance points) updates for 5.17-rc1 from Viresh Kumar: "This updates the documentation to match the latest code." * 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: Documentation: power: Update outdated contents in opp.rst
2021-12-27Documentation: power: Update outdated contents in opp.rstTang Yizhou1-7/+7
Three problems have been revised: 1. CONFIG_PM_OPP no longer depends on CONFIG_PM. 2. opp_find_freq_{ceil, floor} is renamed as dev_pm_opp_find_freq_{ceil, floor}. 3. Make it clear that the 'opp' struct is actually dev_pm_opp. Signed-off-by: Tang Yizhou <tangyizhou@huawei.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2021-12-17PM: runtime: Capture device status before disabling runtime PMRafael J. Wysocki1-4/+10
In some cases (for example, during system-wide suspend and resume of devices) it is useful to know whether or not runtime PM has ever been enabled for a given device and, if so, what the runtime PM status of it had been right before runtime PM was disabled for it last time. For this reason, introduce a new struct dev_pm_info field called last_status that will be used for capturing the runtime PM status of the device when its power.disable_depth counter changes from 0 to 1. The new field will be set to RPM_INVALID to start with and whenever power.disable_depth changes from 1 to 0, so it will be valid only when runtime PM of the device is currently disabled, but it has been enabled at least once. Immediately use power.last_status in rpm_resume() to make it handle the case when PM runtime is disabled for the device, but its runtime PM status is RPM_ACTIVE more consistently. Namely, make it return 1 if power.last_status is also equal to RPM_ACTIVE in that case (the idea being that if the status was RPM_ACTIVE last time when power.disable_depth was changing from 0 to 1 and it is still RPM_ACTIVE, it can be assumed to reflect what happened to the device last time when it was using runtime PM) and -EACCES otherwise. Update the documentation to provide a description of last_status and change the description of pm_runtime_resume() in it to reflect the new behavior of rpm_active(). While at it, rearrange the code in pm_runtime_enable() to be more straightforward and replace the WARN() macro in it with a pr_warn() invocation which is less disruptive. Link: https://lore.kernel.org/linux-pm/20211026222626.39222-1-ulf.hansson@linaro.org/t/#u Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-10Documentation: power: Describe 'advanced' and 'simple' EM modelsLukasz Luba1-0/+22
The Energy Model (EM) can be registered in two ways: 1) Using a helper function, which under the hood relies on OPP framework and DT entry in CPU node: 'dynamic-power-coefficient'. This is a 'simple' EM because it's tied to the math formula: Power = dynamic-power-coefficient * V^2 * f 2) Using em_dev_register_perf_domain() API function with a driver custom callback which provides power for each performance state. This is 'advanced' EM, since it can better reflect real power measurements for each performance state. It's not limited to any math formula and can better reflect real physics of the device. Add description of these two methods to the documentation, so developers could choose the suitable registration method (option). Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-10Documentation: power: Add description about new callback for EM registrationLukasz Luba1-15/+16
The Energy Model (EM) registration for CPUs should now be done using a dedicated callback added recently into CPUFreq framework and drivers. Commit c17495b01b72 ("cpufreq: Add callback to register with energy model") The callback guaranties that the EM registration is called at the right time during driver setup. To avoid mistakes update the documentation to align with the existing code implementation. Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-09-07Documentation: power: include kernel-doc in Energy Model docLukasz Luba1-3/+12
Improve the existing documentation of the Energy Model and add kernel-doc comments. This extends an API description and helps better understanding the usage. Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-11PM: runtime: Clarify documentation when callbacks are unassignedUlf Hansson1-0/+9
Recent changes to the PM core allows ->runtime_suspend|resume callbacks to be unassigned. In the earlier behaviour the PM core would return -ENOSYS, when trying to runtime resume a device, for example. Let's update the documentation to clarify this. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-05-31PM: runtime: document common mistake with pm_runtime_get_sync()Krzysztof Kozlowski1-1/+5
pm_runtime_get_sync(), contradictory to intuition, does not drop the runtime PM usage counter on errors which lead to several wrong usages in drivers (missing the put). pm_runtime_resume_and_get() was added as a better implementation so document the preference of using it, hoping it will stop bad patterns. Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> [ rjw: Documentation change edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-29Merge tag 'for-v5.13' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply Pull power supply and reset updates from Sebastian Reichel: "battery/charger driver changes: - core: - provide function stubs if CONFIG_POWER_SUPPLY=n - reduce loglevel for probe defer info - surface: - new battery and charger drivers for Surface - bq27xxx: - add bq78z100 support - fix current_now/power_avg for newer chips - cw2015: - add CHARGE_NOW support - ab8500: - drop pdata support - convert most DT bindings to YAML - lots of minor fixes and cleanups reset drivers: - ltc2952-poweroff: - make trigger delay configurable from DT - minor fixes and cleanups" * tag 'for-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply: (97 commits) power: supply: cpcap-battery: fix invalid usage of list cursor power: supply: bq256xx: add kerneldoc for structure members power: supply: act8945a: correct kerneldoc power: supply: max17040: remove unneeded double cast power: supply: max17040: handle device_property_read_u8_array() failure power: supply: max14577: remove unneeded variable initialization power: supply: surface-charger: Make symbol 'surface_ac_pm_ops' static power: supply: surface-battery: Make some symbols static power: reset: restart-poweroff: Add missing MODULE_DEVICE_TABLE power: reset: hisi-reboot: add missing MODULE_DEVICE_TABLE power: supply: s3c_adc_battery: fix possible use-after-free in s3c_adc_bat_remove() power: supply: generic-adc-battery: fix possible use-after-free in gab_remove() power: supply: Add AC driver for Surface Aggregator Module power: supply: Add battery driver for Surface Aggregator Module power: supply: bq25980: Move props from battery node power: supply: core: Use true and false for bool variable power: supply: goldfish: Remove the GOLDFISH dependency power: reset: ltc2952: make trigger delay configurable power: supply: cpcap-charger: Simplify bool conversion power: supply: cpcap-charger: Add usleep to cpcap charger to avoid usb plug bounce ...
2021-04-09PM: runtime: Add documentation for pm_runtime_resume_and_get()Alan Stern1-0/+4
Commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter") added a new runtime-PM API function without updating the documentation in runtime_pm.rst. Add the missing documentation. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Fixes: dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-02dt-bindings: power: update battery.yaml referenceMauro Carvalho Chehab1-1/+1
Changesets: 70c23e62d20c ("dt-bindings: power: supply: Fix remaining battery.txt links") and: 471dec8023d1 ("dt-bindings: power: Convert battery.txt to battery.yaml") renamed: Documentation/devicetree/bindings/power/supply/battery.txt to: Documentation/devicetree/bindings/power/supply/battery.yaml. Update its cross-reference accordingly. Fixes: 70c23e62d20c ("dt-bindings: power: supply: Fix remaining battery.txt links") Fixes: 471dec8023d1 ("dt-bindings: power: Convert battery.txt to battery.yaml") Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2021-02-22Merge tag 'docs-5.12' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull documentation updates from Jonathan Corbet: "It has been a relatively quiet cycle in docsland. - As promised, the minimum Sphinx version to build the docs is now 1.7, and we have dropped support for Python 2 entirely. That allowed the removal of a bunch of compatibility code. - A set of treewide warning fixups from Mauro that I applied after it became clear nobody else was going to deal with them. - The automarkup mechanism can now create cross-references from relative paths to RST files. - More translations, typo fixes, and warning fixes" * tag 'docs-5.12' of git://git.lwn.net/linux: (75 commits) docs: kernel-hacking: be more civil docs: Remove the Microsoft rhetoric Documentation/admin-guide: kernel-parameters: Update nohlt section doc/admin-guide: fix spelling mistake: "perfomance" -> "performance" docs: Document cross-referencing using relative path docs: Enable usage of relative paths to docs on automarkup docs: thermal: fix spelling mistakes Documentation: admin-guide: Update kvm/xen config option docs: Make syscalls' helpers naming consistent coding-style.rst: Avoid comma statements Documentation: /proc/loadavg: add 3 more field descriptions Documentation/submitting-patches: Add blurb about backtraces in commit messages Docs: drop Python 2 support Move our minimum Sphinx version to 1.7 Documentation: input: define ABS_PRESSURE/ABS_MT_PRESSURE resolution as grams scripts/kernel-doc: add internal hyperlink to DOC: sections Update Documentation/admin-guide/sysctl/fs.rst docs: Update DTB format references docs: zh_CN: add iio index.rst translation docs/zh_CN: add iio ep93xx_adc.rst translation ...
2021-02-15Merge branches 'powercap' and 'pm-misc'Rafael J. Wysocki2-0/+213
* powercap: powercap: intel_rapl: Use topology interface in rapl_init_domains() powercap: intel_rapl: Use topology interface in rapl_add_package() powercap/intel_rapl: add support for AlderLake Mobile powercap/drivers/dtpm: Fix size of object being allocated powercap/drivers/dtpm: Fix an IS_ERR() vs NULL check powercap/drivers/dtpm: Fix some missing unlock bugs powercap/drivers/dtpm: Fix a double shift bug powercap/drivers/dtpm: Fix __udivdi3 and __aeabi_uldivmod unresolved symbols powercap/drivers/dtpm: Add CPU energy model based support powercap/drivers/dtpm: Add API for dynamic thermal power management Documentation/powercap/dtpm: Add documentation for dtpm units: Add Watt units * pm-misc: PM: Kconfig: remove unneeded "default n" options PM: EM: update Kconfig description and drop "default n" option
2021-01-27PM: runtime: Fix typos and grammarBjorn Helgaas1-7/+7
Fix minor typos and grammatical issues. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-11Documentation: Replace lkml.org links with loreJoe Perches1-1/+1
Replace the lkml.org links with lore to better use a single source that's more likely to stay available long-term. Done by bash script: cvt_lkml_to_lore () { tmpfile=$(mktemp ./.cvt_links.XXXXXXX) header=$(echo $1 | sed 's@/lkml/@/lkml/headers/@') wget -qO - $header > $tmpfile if [[ $? == 0 ]] ; then link=$(grep -i '^Message-Id:' $tmpfile | head -1 | \ sed -r -e 's/^\s*Message-Id:\s*<\s*//' -e 's/\s*>\s*$//' -e 's@^@https://lore.kernel.org/r/@') # echo "testlink: $link" if [ -n "$link" ] ; then wget -qO - $link > /dev/null if [[ $? == 0 ]] ; then echo $link fi fi fi rm -f $tmpfile } git grep -P -o "\bhttps?://(?:www.)?lkml.org/lkml[\/\w]+" $@ | while read line ; do echo $line file=$(echo $line | cut -f1 -d':') link=$(echo $line | cut -f2- -d':') newlink=$(cvt_lkml_to_lore $link) if [[ -n "$newlink" ]] ; then sed -i -e "s#\b$link\b#$newlink#" $file fi done Link: https://lore.kernel.org/patchwork/patch/1265849/#1462688 Signed-off-by: Joe Perches <joe@perches.com> Link: https://lore.kernel.org/r/77cdb7f32cfb087955bfc3600b86c40bed5d4104.camel@perches.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-22Documentation/powercap/dtpm: Add documentation for dtpmDaniel Lezcano2-0/+213
The dynamic thermal and power management is a technique to dynamically adjust the power consumption of different devices in order to ensure a global thermal constraint. An userspace daemon is usually monitoring the temperature and the power to take immediate action on the device. The DTPM framework provides an unified API to userspace to act on the power. Document this framework. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-10PM: EM: Update Energy Model with new flag indicating power scaleLukasz Luba1-5/+12
Update description and meaning of a new flag, which indicates the type of power scale used for a registered Energy Model (EM) device. Reviewed-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-10PM: EM: Clarify abstract scale usage for power values in Energy ModelLukasz Luba1-0/+13
The Energy Model (EM) can store power values in milli-Watts or in abstract scale. This might cause issues in the subsystems which use the EM for estimating the device power, such as: - mixing of different scales in a subsystem which uses multiple (cooling) devices (e.g. thermal Intelligent Power Allocation (IPA)) - assuming that energy [milli-Joules] can be derived from the EM power values which might not be possible since the power scale doesn't have to be in milli-Watts To avoid misconfiguration add the requisite documentation to the EM and related subsystems: EAS and IPA. Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-09-29PCI/PM: Rename pci_dev.d3_delay to d3hot_delayKrzysztof Wilczyński1-1/+1
PCI devices support two variants of the D3 power state: D3hot (main power present) D3cold (main power removed). Previously struct pci_dev contained: unsigned int d3_delay; /* D3->D0 transition time in ms */ unsigned int d3cold_delay; /* D3cold->D0 transition time in ms */ "d3_delay" refers specifically to the D3hot state. Rename it to "d3hot_delay" to avoid ambiguity and align with the ACPI "_DSM for Specifying Device Readiness Durations" in the PCI Firmware spec r3.2, sec 4.6.9. There is no change to the functionality. Link: https://lore.kernel.org/r/20200730210848.1578826-1-kw@linux.com Signed-off-by: Krzysztof Wilczyński <kw@linux.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-08-03Merge branches 'pm-sleep', 'pm-domains', 'powercap' and 'pm-tools'Rafael J. Wysocki1-5/+10
* pm-sleep: PM: sleep: spread "const char *" correctness PM: hibernate: fix white space in a few places freezer: Add unsafe version of freezable_schedule_timeout_interruptible() for NFS PM: sleep: core: Emit changed uevent on wakeup_sysfs_add/remove * pm-domains: PM: domains: Restore comment indentation for generic_pm_domain.child_links PM: domains: Fix up terminology with parent/child * powercap: powercap: Add Power Limit4 support powercap: idle_inject: Replace play_idle() with play_idle_precise() in comments powercap: intel_rapl: add support for Sapphire Rapids * pm-tools: pm-graph v5.7 - important s2idle fixes cpupower: Replace HTTP links with HTTPS ones cpupower: Fix NULL but dereferenced coccicheck errors cpupower: Fix comparing pointer to 0 coccicheck warns
2020-07-27powercap: Add Power Limit4 supportSumeet Pawnikar1-5/+10
Modern Intel Mobile platforms support power limit4 (PL4), which is the SoC package level maximum power limit (in Watts). It can be used to preemptively limits potential SoC power to prevent power spikes from tripping the power adapter and battery over-current protection. This patch enables this feature by exposing package level peak power capping control to userspace via RAPL sysfs interface. With this, application like DTPF can modify PL4 power limit, the similar way of other package power limit (PL1). As this feature is not tested on previous generations, here it is enabled only for the platform that has been verified to work, for safety concerns. Signed-off-by: Sumeet Pawnikar <sumeet.r.pawnikar@intel.com> Co-developed-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-06-24Documentation: power: update Energy Model descriptionLukasz Luba1-60/+75
The Energy Model framework supports also other devices than CPUs. Update related information and add description for the new usage. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Quentin Perret <qperret@google.com> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-06-02Merge tag 'pm-5.8-rc1' of ↵Linus Torvalds1-30/+28
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These rework the system-wide PM driver flags, make runtime switching of cpuidle governors easier, improve the user space hibernation interface code, add intel-speed-select interface documentation, add more debug messages to the ACPI code handling suspend to idle, update the cpufreq core and drivers, fix a minor issue in the cpuidle core and update two cpuidle drivers, improve the PM-runtime framework, update the Intel RAPL power capping driver, update devfreq core and drivers, and clean up the cpupower utility. Specifics: - Rework the system-wide PM driver flags to make them easier to understand and use and update their documentation (Rafael Wysocki, Alan Stern). - Allow cpuidle governors to be switched at run time regardless of the kernel configuration and update the related documentation accordingly (Hanjun Guo). - Improve the resume device handling in the user space hibernarion interface code (Domenico Andreoli). - Document the intel-speed-select sysfs interface (Srinivas Pandruvada). - Make the ACPI code handing suspend to idle print more debug messages to help diagnose issues with it (Rafael Wysocki). - Fix a helper routine in the cpufreq core and correct a typo in the struct cpufreq_driver kerneldoc comment (Rafael Wysocki, Wang Wenhu). - Update cpufreq drivers: - Make the intel_pstate driver start in the passive mode by default on systems without HWP (Rafael Wysocki). - Add i.MX7ULP support to the imx-cpufreq-dt driver and add i.MX7ULP to the cpufreq-dt-platdev blacklist (Peng Fan). - Convert the qoriq cpufreq driver to a platform one, make the platform code create a suitable device object for it and add platform dependencies to it (Mian Yousaf Kaukab, Geert Uytterhoeven). - Fix wrong compatible binding in the qcom driver (Ansuel Smith). - Build the omap driver by default for ARCH_OMAP2PLUS (Anders Roxell). - Add r8a7742 SoC support to the dt cpufreq driver (Lad Prabhakar). - Update cpuidle core and drivers: - Fix three reference count leaks in error code paths in the cpuidle core (Qiushi Wu). - Convert Qualcomm SPM to a generic cpuidle driver (Stephan Gerhold). - Fix up the execution order when entering a domain idle state in the PSCI driver (Ulf Hansson). - Fix a reference counting issue related to clock management and clean up two oddities in the PM-runtime framework (Rafael Wysocki, Andy Shevchenko). - Add ElkhartLake support to the Intel RAPL power capping driver and remove an unused local MSR definition from it (Jacob Pan, Sumeet Pawnikar). - Update devfreq core and drivers: - Replace strncpy() with strscpy() in the devfreq core and use lockdep asserts instead of manual checks for a locked mutex in it (Dmitry Osipenko, Krzysztof Kozlowski). - Add a generic imx bus scaling driver and make it register an interconnect device (Leonard Crestez, Gustavo A. R. Silva). - Make the cpufreq notifier in the tegra30 driver take boosting into account and delete an unuseful error message from that driver (Dmitry Osipenko, Markus Elfring). - Remove unneeded semicolon from the cpupower code (Zou Wei)" * tag 'pm-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (51 commits) cpuidle: Fix three reference count leaks PM: runtime: Replace pm_runtime_callbacks_present() PM / devfreq: Use lockdep asserts instead of manual checks for locked mutex PM / devfreq: imx-bus: Fix inconsistent IS_ERR and PTR_ERR PM / devfreq: Replace strncpy with strscpy PM / devfreq: imx: Register interconnect device PM / devfreq: Add generic imx bus scaling driver PM / devfreq: tegra30: Delete an error message in tegra_devfreq_probe() PM / devfreq: tegra30: Make CPUFreq notifier to take into account boosting PM: hibernate: Restrict writes to the resume device PM: runtime: clk: Fix clk_pm_runtime_get() error path cpuidle: Convert Qualcomm SPM driver to a generic CPUidle driver ACPI: EC: PM: s2idle: Extend GPE dispatching debug message ACPI: PM: s2idle: Print type of wakeup debug messages powercap: RAPL: remove unused local MSR define PM: runtime: Make clear what we do when conditions are wrong in rpm_suspend() Documentation: admin-guide: pm: Document intel-speed-select PM: hibernate: Split off snapshot dev option PM: hibernate: Incorporate concurrency handling Documentation: ABI: make current_governer_ro as a candidate for removal ...
2020-05-07cpu/hotplug: Remove disable_nonboot_cpus()Qais Yousef1-3/+3
The single user could have called freeze_secondary_cpus() directly. Since this function was a source of confusion, remove it as it's just a pointless wrapper. While at it, rename enable_nonboot_cpus() to thaw_secondary_cpus() to preserve the naming symmetry. Done automatically via: git grep -l enable_nonboot_cpus | xargs sed -i 's/enable_nonboot_cpus/thaw_secondary_cpus/g' Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Link: https://lkml.kernel.org/r/20200430114004.17477-1-qais.yousef@arm.com
2020-04-24Documentation: PM: sleep: Update driver flags documentationRafael J. Wysocki1-21/+22
Update the documentation of the driver flags for system-wide power management to reflect the current code flows and be more consistent. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-24PM: sleep: core: Rename DPM_FLAG_LEAVE_SUSPENDEDRafael J. Wysocki1-1/+1
Rename DPM_FLAG_LEAVE_SUSPENDED to DPM_FLAG_MAY_SKIP_RESUME which matches its purpose more closely. No functional impact. Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> # for I2C Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Bjorn Helgaas <bhelgaas@google.com>