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2017-11-27PCI / PM: Support for LEAVE_SUSPENDED driver flagRafael J. Wysocki
Add support for DPM_FLAG_LEAVE_SUSPENDED to the PCI bus type by making it (a) set the power.may_skip_resume status bit for devices that, from its perspective, may be left in suspend after system wakeup from sleep and (b) return early from pci_pm_resume_noirq() for devices whose remaining resume callbacks during the transition under way are going to be skipped by the PM core. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2017-11-13Merge tag 'pm-4.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "There are no real big ticket items here this time. The most noticeable change is probably the relocation of the OPP (Operating Performance Points) framework to its own directory under drivers/ as it has grown big enough for that. Also Viresh is now going to maintain it and send pull requests for it to me, so you will see this change in the git history going forward (but still not right now). Another noticeable set of changes is the modifications of the PM core, the PCI subsystem and the ACPI PM domain to allow of more integration between system-wide suspend/resume and runtime PM. For now it's just a way to avoid resuming devices from runtime suspend unnecessarily during system suspend (if the driver sets a flag to indicate its readiness for that) and in the works is an analogous mechanism to allow devices to stay suspended after system resume. In addition to that, we have some changes related to supporting frequency-invariant CPU utilization metrics in the scheduler and in the schedutil cpufreq governor on ARM and changes to add support for device performance states to the generic power domains (genpd) framework. The rest is mostly fixes and cleanups of various sorts. Specifics: - Relocate the OPP (Operating Performance Points) framework to its own directory under drivers/ and add support for power domain performance states to it (Viresh Kumar). - Modify the PM core, the PCI bus type and the ACPI PM domain to support power management driver flags allowing device drivers to specify their capabilities and preferences regarding the handling of devices with enabled runtime PM during system suspend/resume and clean up that code somewhat (Rafael Wysocki, Ulf Hansson). - Add frequency-invariant accounting support to the task scheduler on ARM and ARM64 (Dietmar Eggemann). - Fix PM QoS device resume latency framework to prevent "no restriction" requests from overriding requests with specific requirements and drop the confusing PM_QOS_FLAG_REMOTE_WAKEUP device PM QoS flag (Rafael Wysocki). - Drop legacy class suspend/resume operations from the PM core and drop legacy bus type suspend and resume callbacks from ARM/locomo (Rafael Wysocki). - Add min/max frequency support to devfreq and clean it up somewhat (Chanwoo Choi). - Rework wakeup support in the generic power domains (genpd) framework and update some of its users accordingly (Geert Uytterhoeven). - Convert timers in the PM core to use timer_setup() (Kees Cook). - Add support for exposing the SLP_S0 (Low Power S0 Idle) residency counter based on the LPIT ACPI table on Intel platforms (Srinivas Pandruvada). - Add per-CPU PM QoS resume latency support to the ladder cpuidle governor (Ramesh Thomas). - Fix a deadlock between the wakeup notify handler and the notifier removal in the ACPI core (Ville Syrjälä). - Fix a cpufreq schedutil governor issue causing it to use stale cached frequency values sometimes (Viresh Kumar). - Fix an issue in the system suspend core support code causing wakeup events detection to fail in some cases (Rajat Jain). - Fix the generic power domains (genpd) framework to prevent the PM core from using the direct-complete optimization with it as that is guaranteed to fail (Ulf Hansson). - Fix a minor issue in the cpuidle core and clean it up a bit (Gaurav Jindal, Nicholas Piggin). - Fix and clean up the intel_idle and ARM cpuidle drivers (Jason Baron, Len Brown, Leo Yan). - Fix a couple of minor issues in the OPP framework and clean it up (Arvind Yadav, Fabio Estevam, Sudeep Holla, Tobias Jordan). - Fix and clean up some cpufreq drivers and fix a minor issue in the cpufreq statistics code (Arvind Yadav, Bhumika Goyal, Fabio Estevam, Gautham Shenoy, Gustavo Silva, Marek Szyprowski, Masahiro Yamada, Robert Jarzmik, Zumeng Chen). - Fix minor issues in the system suspend and hibernation core, in power management documentation and in the AVS (Adaptive Voltage Scaling) framework (Helge Deller, Himanshu Jha, Joe Perches, Rafael Wysocki). - Fix some issues in the cpupower utility and document that Shuah Khan is going to maintain it going forward (Prarit Bhargava, Shuah Khan)" * tag 'pm-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (88 commits) tools/power/cpupower: add libcpupower.so.0.0.1 to .gitignore tools/power/cpupower: Add 64 bit library detection intel_idle: Graceful probe failure when MWAIT is disabled cpufreq: schedutil: Reset cached_raw_freq when not in sync with next_freq freezer: Fix typo in freezable_schedule_timeout() comment PM / s2idle: Clear the events_check_enabled flag cpufreq: stats: Handle the case when trans_table goes beyond PAGE_SIZE cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const cpufreq: arm_big_little: make function arguments and structure pointer const cpuidle: Avoid assignment in if () argument cpuidle: Clean up cpuidle_enable_device() error handling a bit ACPI / PM: Fix acpi_pm_notifier_lock vs flush_workqueue() deadlock PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare() cpuidle: ladder: Add per CPU PM QoS resume latency support PM / QoS: Fix device resume latency framework PM / domains: Rework governor code to be more consistent PM / Domains: Remove gpd_dev_ops.active_wakeup() callback soc: rockchip: power-domain: Use GENPD_FLAG_ACTIVE_WAKEUP soc: mediatek: Use GENPD_FLAG_ACTIVE_WAKEUP ARM: shmobile: pm-rmobile: Use GENPD_FLAG_ACTIVE_WAKEUP ...
2017-11-06PCI / PM: Take SMART_SUSPEND driver flag into accountRafael J. Wysocki
Make the PCI bus type take DPM_FLAG_SMART_SUSPEND into account in its system-wide PM callbacks and make sure that all code that should not run in parallel with pci_pm_runtime_resume() is executed in the "late" phases of system suspend, freeze and poweroff transitions. [Note that the pm_runtime_suspended() check in pci_dev_keep_suspended() is an optimization, because if is not passed, all of the subsequent checks may be skipped and some of them are much more overhead in general.] Also use the observation that if the device is in runtime suspend at the beginning of the "late" phase of a system-wide suspend-like transition, its state cannot change going forward (runtime PM is disabled for it at that time) until the transition is over and the subsequent system-wide PM callbacks should be skipped for it (as they generally assume the device to not be suspended), so add checks for that in pci_pm_suspend_late/noirq(), pci_pm_freeze_late/noirq() and pci_pm_poweroff_late/noirq(). Moreover, if pci_pm_resume_noirq() or pci_pm_restore_noirq() is called during the subsequent system-wide resume transition and if the device was left in runtime suspend previously, its runtime PM status needs to be changed to "active" as it is going to be put into the full-power state, so add checks for that too to these functions. In turn, if pci_pm_thaw_noirq() runs after the device has been left in runtime suspend, the subsequent "thaw" callbacks need to be skipped for it (as they may not work correctly with a suspended device), so set the power.direct_complete flag for the device then to make the PM core skip those callbacks. In addition to the above add a core helper for checking if DPM_FLAG_SMART_SUSPEND is set and the device runtime PM status is "suspended" at the same time, which is done quite often in the new code (and will be done elsewhere going forward too). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2017-11-06PM / core: Add NEVER_SKIP and SMART_PREPARE driver flagsRafael J. Wysocki
The motivation for this change is to provide a way to work around a problem with the direct-complete mechanism used for avoiding system suspend/resume handling for devices in runtime suspend. The problem is that some middle layer code (the PCI bus type and the ACPI PM domain in particular) returns positive values from its system suspend ->prepare callbacks regardless of whether the driver's ->prepare returns a positive value or 0, which effectively prevents drivers from being able to control the direct-complete feature. Some drivers need that control, however, and the PCI bus type has grown its own flag to deal with this issue, but since it is not limited to PCI, it is better to address it by adding driver flags at the core level. To that end, add a driver_flags field to struct dev_pm_info for flags that can be set by device drivers at the probe time to inform the PM core and/or bus types, PM domains and so on on the capabilities and/or preferences of device drivers. Also add two static inline helpers for setting that field and testing it against a given set of flags and make the driver core clear it automatically on driver remove and probe failures. Define and document two PM driver flags related to the direct- complete feature: NEVER_SKIP and SMART_PREPARE that can be used, respectively, to indicate to the PM core that the direct-complete mechanism should never be used for the device and to inform the middle layer code (bus types, PM domains etc) that it can only request the PM core to use the direct-complete mechanism for the device (by returning a positive value from its ->prepare callback) if it also has been requested by the driver. While at it, make the core check pm_runtime_suspended() when setting power.direct_complete so that it doesn't need to be checked by ->prepare callbacks. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-10-12Documentation: fix driver-api doc refsTom Saeger
Make driver-api document refs valid. Signed-off-by: Tom Saeger <tom.saeger@oracle.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-02-06PM / sleep / docs: Convert PM notifiers document to reSTRafael J. Wysocki
Move the document describing PM notifiers (used during system sleep state transitions) to Documentation/driver-api/pm/, convert it to reST and update it to use current terminology. Also replace the remaining references to the old version of it in .txt documents with references to the new one. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-10-24docs: fix locations of several documents that got movedMauro Carvalho Chehab
The previous patch renamed several files that are cross-referenced along the Kernel documentation. Adjust the links to point to the right places. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2015-12-09PCI / PM: Fix small typo in documentationJarkko Nikula
cuased -> caused Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-25PCI / PM: Update runtime PM documentation for PCI devicesRafael J. Wysocki
Section 3.2 "Device Runtime Power Management" of pci.txt has become outdated, so update it to correctly reflect the current code flow. Also update the comment in local_pci_probe() to document the fact that pm_runtime_put_noidle() is not the only runtime PM helper function that can be used to decrement the device's runtime PM usage counter in .probe(). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu>
2010-05-18PM/PCI: Update PCI power management documentationRafael J. Wysocki
I power management document, Documentation/power/pci.txt, is outdated and partially inaccurate. It also is missing some important information about the power management of PCI device. Rewrite it to make it more up to date and more complete. Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2007-07-11PCI: remove useless pci driver methodDavid Brownell
Remove pointless and never-called enable_wake() hook from pci_driver and from documentation. Evidently this was introduced in the 2.4.6 kernel, but there's no evidence it was ever called; and it was rarely implemented. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-05-02PCI Documentation: power/pci.txt fix copy/paste errorRandy Dunlap
Correct function name copy-paste error. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-03-26PCI: Fix up PCI power management docJonathan Corbet
Update the documentation of PCI power management functions. Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-11-30Fix typos in /Documentation : MiscMatt LaPlante
This patch fixes typos in various Documentation txts. The patch addresses some misc words. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03Fix typos in Documentation/: 'D'-'E'Matt LaPlante
This patch fixes typos in various Documentation txts. This patch addresses some words starting with the letters 'D'-'E'. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2005-11-22[PATCH] kernel Doc/ URL correctionsRandy Dunlap
Correct lots of URLs in Documentation/ Also a few minor whitespace cleanups and typo/spello fixes. Sadly there are still a lot of bad URLs remaining. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] suspend: PCI power managment reference implementationpavel@ucw.cz
Added reference implementation of suspend and resume routines. From: Shaohua Li <shaohua.li@intel.com> build fix Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-03[PATCH] PCI: fix stale PCI pm docsPavel Machek
This fixes u32 vs. pm_message_t confusion in documentation, and removes references to no-longer-existing (*save_state), too. With exception of USB (I hope David will fix/apply my patch), this should fix last piece of this confusion... famous last words. Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!