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author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-14 06:43:50 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-14 06:43:50 +0300 |
commit | bd2cd7d5a8f83ddc761025f42a3ca8e56351a6cc (patch) | |
tree | 6ea70f09f32544f895020e198dac632145332cc2 /Documentation/power | |
parent | b29c6ef7bb1257853c1e31616d84f55e561cf631 (diff) | |
parent | 990a848d537e4da966907c8ccec95bc568f2911c (diff) | |
download | linux-bd2cd7d5a8f83ddc761025f42a3ca8e56351a6cc.tar.xz |
Merge tag 'pm-4.15-rc1' of 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
...
Diffstat (limited to 'Documentation/power')
-rw-r--r-- | Documentation/power/pci.txt | 33 | ||||
-rw-r--r-- | Documentation/power/pm_qos_interface.txt | 13 |
2 files changed, 39 insertions, 7 deletions
diff --git a/Documentation/power/pci.txt b/Documentation/power/pci.txt index d17fdf8f45ef..704cd36079b8 100644 --- a/Documentation/power/pci.txt +++ b/Documentation/power/pci.txt @@ -961,6 +961,39 @@ dev_pm_ops to indicate that one suspend routine is to be pointed to by the .suspend(), .freeze(), and .poweroff() members and one resume routine is to be pointed to by the .resume(), .thaw(), and .restore() members. +3.1.19. Driver Flags for Power Management + +The PM core allows device drivers to set flags that influence the handling of +power management for the devices by the core itself and by middle layer code +including the PCI bus type. The flags should be set once at the driver probe +time with the help of the dev_pm_set_driver_flags() function and they should not +be updated directly afterwards. + +The DPM_FLAG_NEVER_SKIP flag prevents the PM core from using the direct-complete +mechanism allowing device suspend/resume callbacks to be skipped if the device +is in runtime suspend when the system suspend starts. That also affects all of +the ancestors of the device, so this flag should only be used if absolutely +necessary. + +The DPM_FLAG_SMART_PREPARE flag instructs the PCI bus type to only return a +positive value from pci_pm_prepare() if the ->prepare callback provided by the +driver of the device returns a positive value. That allows the driver to opt +out from using the direct-complete mechanism dynamically. + +The DPM_FLAG_SMART_SUSPEND flag tells the PCI bus type that from the driver's +perspective the device can be safely left in runtime suspend during system +suspend. That causes pci_pm_suspend(), pci_pm_freeze() and pci_pm_poweroff() +to skip resuming the device from runtime suspend unless there are PCI-specific +reasons for doing that. Also, it causes pci_pm_suspend_late/noirq(), +pci_pm_freeze_late/noirq() and pci_pm_poweroff_late/noirq() to return early +if the device remains in runtime suspend in the beginning of the "late" phase +of the system-wide transition under way. Moreover, if the device is in +runtime suspend in pci_pm_resume_noirq() or pci_pm_restore_noirq(), its runtime +power management status will be changed to "active" (as it is going to be put +into D0 going forward), but if it is in runtime suspend in pci_pm_thaw_noirq(), +the function will set the power.direct_complete flag for it (to make the PM core +skip the subsequent "thaw" callbacks for it) and return. + 3.2. Device Runtime Power Management ------------------------------------ In addition to providing device power management callbacks PCI device drivers diff --git a/Documentation/power/pm_qos_interface.txt b/Documentation/power/pm_qos_interface.txt index 21d2d48f87a2..19c5f7b1a7ba 100644 --- a/Documentation/power/pm_qos_interface.txt +++ b/Documentation/power/pm_qos_interface.txt @@ -98,8 +98,7 @@ Values are updated in response to changes of the request list. The target values of resume latency and active state latency tolerance are simply the minimum of the request values held in the parameter list elements. The PM QoS flags aggregate value is a gather (bitwise OR) of all list elements' -values. Two device PM QoS flags are defined currently: PM_QOS_FLAG_NO_POWER_OFF -and PM_QOS_FLAG_REMOTE_WAKEUP. +values. One device PM QoS flag is defined currently: PM_QOS_FLAG_NO_POWER_OFF. Note: The aggregated target values are implemented in such a way that reading the aggregated value does not require any locking mechanism. @@ -153,14 +152,14 @@ PM QoS list of resume latency constraints and remove sysfs attribute pm_qos_resume_latency_us from the device's power directory. int dev_pm_qos_expose_flags(device, value) -Add a request to the device's PM QoS list of flags and create sysfs attributes -pm_qos_no_power_off and pm_qos_remote_wakeup under the device's power directory -allowing user space to change these flags' value. +Add a request to the device's PM QoS list of flags and create sysfs attribute +pm_qos_no_power_off under the device's power directory allowing user space to +change the value of the PM_QOS_FLAG_NO_POWER_OFF flag. void dev_pm_qos_hide_flags(device) Drop the request added by dev_pm_qos_expose_flags() from the device's PM QoS list -of flags and remove sysfs attributes pm_qos_no_power_off and pm_qos_remote_wakeup -under the device's power directory. +of flags and remove sysfs attribute pm_qos_no_power_off from the device's power +directory. Notification mechanisms: The per-device PM QoS framework has a per-device notification tree. |