Commit Graph

25 Commits

Author SHA1 Message Date
Viresh Kumar
2a79ea5ec5 PM / QOS: Pass request type to dev_pm_qos_read_value()
In order to allow dev_pm_qos_read_value() to read values for different
QoS requests, pass request type as a parameter to these routines.

For now, it only supports resume-latency request type but will be
extended to frequency limit (min/max) constraints later on.

Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-07-04 10:40:54 +02:00
Viresh Kumar
8262331eaa PM / QOS: Rename __dev_pm_qos_read_value() and dev_pm_qos_raw_read_value()
dev_pm_qos_read_value() will soon need to support more constraint types
(min/max frequency) and will have another argument to it, i.e. type of
the constraint. While that is fine for the existing users of
dev_pm_qos_read_value(), but not that optimal for the callers of
__dev_pm_qos_read_value() and dev_pm_qos_raw_read_value() as all the
callers of these two routines are only looking for resume latency
constraint.

Lets make these two routines care only about the resume latency
constraint and rename them to __dev_pm_qos_resume_latency() and
dev_pm_qos_raw_resume_latency().

Suggested-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-07-04 10:40:54 +02:00
Linus Torvalds
cf482a49af Driver core/kobject patches for 5.2-rc1
Here is the "big" set of driver core patches for 5.2-rc1
 
 There are a number of ACPI patches in here as well, as Rafael said they
 should go through this tree due to the driver core changes they
 required.  They have all been acked by the ACPI developers.
 
 There are also a number of small subsystem-specific changes in here, due
 to some changes to the kobject core code.  Those too have all been acked
 by the various subsystem maintainers.
 
 As for content, it's pretty boring outside of the ACPI changes:
   - spdx cleanups
   - kobject documentation updates
   - default attribute groups for kobjects
   - other minor kobject/driver core fixes
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core/kobject updates from Greg KH:
 "Here is the "big" set of driver core patches for 5.2-rc1

  There are a number of ACPI patches in here as well, as Rafael said
  they should go through this tree due to the driver core changes they
  required. They have all been acked by the ACPI developers.

  There are also a number of small subsystem-specific changes in here,
  due to some changes to the kobject core code. Those too have all been
  acked by the various subsystem maintainers.

  As for content, it's pretty boring outside of the ACPI changes:
   - spdx cleanups
   - kobject documentation updates
   - default attribute groups for kobjects
   - other minor kobject/driver core fixes

  All have been in linux-next for a while with no reported issues"

* tag 'driver-core-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (47 commits)
  kobject: clean up the kobject add documentation a bit more
  kobject: Fix kernel-doc comment first line
  kobject: Remove docstring reference to kset
  firmware_loader: Fix a typo ("syfs" -> "sysfs")
  kobject: fix dereference before null check on kobj
  Revert "driver core: platform: Fix the usage of platform device name(pdev->name)"
  init/config: Do not select BUILD_BIN2C for IKCONFIG
  Provide in-kernel headers to make extending kernel easier
  kobject: Improve doc clarity kobject_init_and_add()
  kobject: Improve docs for kobject_add/del
  driver core: platform: Fix the usage of platform device name(pdev->name)
  livepatch: Replace klp_ktype_patch's default_attrs with groups
  cpufreq: schedutil: Replace default_attrs field with groups
  padata: Replace padata_attr_type default_attrs field with groups
  irqdesc: Replace irq_kobj_type's default_attrs field with groups
  net-sysfs: Replace ktype default_attrs field with groups
  block: Replace all ktype default_attrs with groups
  samples/kobject: Replace foo_ktype's default_attrs field with groups
  kobject: Add support for default attribute groups to kobj_type
  driver core: Postpone DMA tear-down until after devres release for probe failure
  ...
2019-05-07 13:01:40 -07:00
Ulf Hansson
e94999688e PM / Domains: Add genpd governor for CPUs
After some preceding changes, PM domains managed by genpd may contain
CPU devices, so idle state residency values should be taken into
account during the state selection process. [The residency value is
the minimum amount of time to be spent by a CPU (or a group of CPUs)
in an idle state in order to save more energy than could be saved
by picking up a shallower idle state.]

For this purpose, add a new genpd governor, pm_domain_cpu_gov, to be
used for selecting idle states of PM domains with CPU devices attached
either directly or through subdomains.

The new governor computes the minimum expected idle duration for all
online CPUs attached to a PM domain and its subdomains.  Next, it
finds the deepest idle state whose target residency is within the
expected idle duration and selects it as the target idle state of
the domain.

It should be noted that the minimum expected idle duration computation
is based on the closest timer event information stored in the per-CPU
variables cpuidle_devices for all of the CPUs in the domain.  That
needs to be revisited in future, as obviously there are other reasons
why a CPU may be woken up from idle.

Co-developed-by: Lina Iyer <lina.iyer@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-11 22:41:01 +02:00
Greg Kroah-Hartman
5de363b66a drivers: base: power: add proper SPDX identifiers on files that did not have them.
There were a few files in the driver core power code that did not have
SPDX identifiers on them, so fix that up.  At the same time, remove the
"free form" text that specified the license of the file, as that is
impossible for any tool to properly parse.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-04 20:03:40 +02:00
Aisheng Dong
d9dfca7f81 PM / domains: Remove one unnecessary blank line
Remove one unnecessary blank line

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-03-11 11:26:45 +01:00
Rafael J. Wysocki
0759e80b84 PM / QoS: Fix device resume latency framework
The special value of 0 for device resume latency PM QoS means
"no restriction", but there are two problems with that.

First, device resume latency PM QoS requests with 0 as the
value are always put in front of requests with positive
values in the priority lists used internally by the PM QoS
framework, causing 0 to be chosen as an effective constraint
value.  However, that 0 is then interpreted as "no restriction"
effectively overriding the other requests with specific
restrictions which is incorrect.

Second, the users of device resume latency PM QoS have no
way to specify that *any* resume latency at all should be
avoided, which is an artificial limitation in general.

To address these issues, modify device resume latency PM QoS to
use S32_MAX as the "no constraint" value and 0 as the "no
latency at all" one and rework its users (the cpuidle menu
governor, the genpd QoS governor and the runtime PM framework)
to follow these changes.

Also add a special "n/a" value to the corresponding user space I/F
to allow user space to indicate that it cannot accept any resume
latencies at all for the given device.

Fixes: 85dc0b8a40 (PM / QoS: Make it possible to expose PM QoS latency constraints)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=197323
Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-11-08 12:14:51 +01:00
Rafael J. Wysocki
704d2ce660 PM / domains: Rework governor code to be more consistent
The genpd governor currently uses negative PM QoS values to indicate
the "no suspend" condition and 0 as "no restriction", but it doesn't
use them consistently.  Moreover, it tries to refresh QoS values for
already suspended devices in a quite questionable way.

For the above reasons, rework it to be a bit more consistent.

First off, note that dev_pm_qos_read_value() in
dev_update_qos_constraint() and __default_power_down_ok() is
evaluated for devices in suspend.  Moreover, that only happens if the
effective_constraint_ns value for them is negative (meaning "no
suspend").  It is not evaluated in any other cases, so effectively
the QoS values are only updated for devices in suspend that should
not have been suspended in the first place.  In all of the other
cases, the QoS values taken into account are the effective ones from
the time before the device has been suspended, so generally devices
need to be resumed and suspended again for new QoS values to take
effect anyway.  Thus evaluating dev_update_qos_constraint() in
those two places doesn't make sense at all, so drop it.

Second, initialize effective_constraint_ns to 0 ("no constraint")
rather than to (-1) ("no suspend"), which makes more sense in
general and in case effective_constraint_ns is never updated
(the device is in suspend all the time or it is never suspended)
it doesn't affect the device's parent and so on.

Finally, rework default_suspend_ok() to explicitly handle the
"no restriction" and "no suspend" special cases.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-11-08 12:13:13 +01:00
Krzysztof Kozlowski
268cd2ed3d PM / Domains: Fix missing default_power_down_ok comment
Commit fc5cbf0c94 (PM / Domains: Support for multiple states) split
out some code out of default_power_down_ok() function so the
documentation has to be moved to appropriate place.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-06-29 01:24:36 +02:00
Ulf Hansson
9df3921e02 PM / Domains: Rename stop_ok to suspend_ok for the genpd governor
The genpd governor validates the latency constraints to find out whether
it's acceptable to runtime suspend a device. Earlier this validation was
made to know whether it was okay to invoke the ->stop() callback for the
device, hence the governor used the name "stop_ok" for the related
variables.

To clarify the code around this, let's rename these variables from
"stop_ok" to "suspend_ok".

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-22 02:29:17 +02:00
Axel Haslam
fc5cbf0c94 PM / Domains: Support for multiple states
Some hardware (eg. OMAP), has the ability to enter different low power
modes for a given power domain. This allows for more fine grained control
over the power state of the platform. As a typical example, some registers
of the hardware may be implemented with retention flip-flops and be able
to retain their state at lower voltages allowing for faster on/off
latencies and an increased window of opportunity to enter an intermediate
low power state other than "off"

When trying to set a power domain to off, the genpd governor will choose
the deepest state that will respect the qos constraints of all the devices
and sub-domains on the power domain. The state chosen by the governor is
saved in the "state_idx" field of the generic_pm_domain structure and
shall be used by the power_off and power_on callbacks to perform the
necessary actions to set the power domain into (and out of) the state
indicated by state_idx.

States must be declared in ascending order from shallowest to deepest,
deepest meaning the state which takes longer to enter and exit.

For platforms that don't declare any states, a single a single "off"
state is used. Once all platforms are converted to use the state array,
the legacy on/off latencies will be removed.

[ Lina: Modified genpd state initialization and remove use of
        save_state_latency_ns in genpd timing data ]
Suggested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Axel Haslam <ahaslam+renesas@baylibre.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-15 23:18:15 +01:00
Ulf Hansson
712caed435 PM / Domains: Validate cases of a non-bound driver in genpd governor
Recently genpd removed the requirement of a having a driver bound for its
attached devices to allow genpd to power off. That change should also have
removed a corresponding validation in the governor, let's correct that.

Fixes: 298cd0f088 (PM / Domains: Remove dev->driver check for runtime)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-02 15:21:21 +01:00
Ulf Hansson
2b1d88cda3 PM / Domains: Merge measurements for PM QoS device latencies
Measure latency does by itself contribute to an increased latency, thus we
should avoid it when it isn't needed.

By merging the latency measurements for the ->save_state() and the
->stop() callbacks, we get one measurement instead of two and we get one
value to store instead of two. Let's also apply the likewise change for
the ->start() and ->restore_state() callbacks.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Lina Iyer <lina.iyer@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-28 04:33:04 +01:00
Ulf Hansson
a98f1b78ec PM / Domains: Fix validation of latency constraints in genpd governor
Commit ba2bbfbf63 (PM / Domains: Remove intermediate states from the
power off sequence) changed the power off sequence in genpd. That also
required some updates regarding the validation of latency constraints in
the genpd governor. Unfortunate that wasn't covered, so let's fix this.

From a runtime PM and latency point of view, we need to consider the worst
case scenario while validating latency constraints. That's typically when
a call to pm_runtime_get_sync() needs to wait for a ongoing runtime
suspend operation to be carried out, as it then also needs to wait for the
device to be runtime resumed again.

The above mentioned commit made the genpd governor's ->stop_ok() callback
responsible of validating genpd's device's runtime suspend/resume latency.
In other words, the constraint needs to be validated towards the relevant
latencies present in genpd's ->runtime_suspend|resume() callbacks.

Earlier, that included latencies from the ->stop|start() callbacks, but as
->save|restore_state() are now also being invoked from genpd's
->runtime_suspend|resume() and to comply with the worst case scenario,
let's take also those latencies into account.

Fixes: ba2bbfbf63 (PM / Domains: Remove intermediate states from the power off sequence)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-14 02:34:43 +02:00
Rafael J. Wysocki
d30d819dc8 PM: Drop CONFIG_PM_RUNTIME from the driver core
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM or even may be dropped entirely in some cases.

Replace CONFIG_PM_RUNTIME with CONFIG_PM in the PM core code.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-04 00:46:58 +01:00
Ulf Hansson
0f574d4c3a PM / domains: Remove default_stop_ok() API
There are currently no need to export default_stop_ok() as an API,
instead let's keep it local to the PM domain governor.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09 00:46:13 +02:00
Paul Gortmaker
4272b9611c drivers/base: delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Cc: Len Brown <len.brown@intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-14 14:31:37 -08:00
Rafael J. Wysocki
b723b0eb91 PM / Domains: Fix computation of maximum domain off time
The default domain power off governor function for generic PM
domains, default_power_down_ok(), may violate subdomain maximum
off time limit by allowing the master domain to be off for too
long.  Namely, it only finds the minium of all device maximum
off times over the domain's devices and uses that to compute the
domain's maximum off time, but it should do the same for the
subdomains.

Fix this problem by modifying default_power_down_ok() to compute
the given domain's maximum off time as the difference between the
minimum off time over all devices and subdomains in the domain and
its power on latency.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-11 21:11:44 +02:00
Rafael J. Wysocki
6ff7bb0d02 PM / Domains: Cache device stop and domain power off governor results, v3
The results of the default device stop and domain power off governor
functions for generic PM domains, default_stop_ok() and
default_power_down_ok(), depend only on the timing data of devices,
which are static, and on their PM QoS constraints.  Thus, in theory,
these functions only need to carry out their computations, which may
be time consuming in general, when it is known that the PM QoS
constraint of at least one of the devices in question has changed.

Use the PM QoS notifiers of devices to implement that.  First,
introduce new fields, constraint_changed and max_off_time_changed,
into struct gpd_timing_data and struct generic_pm_domain,
respectively, and register a PM QoS notifier function when adding
a device into a domain that will set those fields to 'true' whenever
the device's PM QoS constraint is modified.  Second, make
default_stop_ok() and default_power_down_ok() use those fields to
decide whether or not to carry out their computations from scratch.

The device and PM domain hierarchies are taken into account in that
and the expense is that the changes of PM QoS constraints of
suspended devices will not be taken into account immediately, which
isn't guaranteed anyway in general.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-05 21:51:58 +02:00
Rafael J. Wysocki
dd8683e97f PM / Domains: Rework default domain power off governor function, v2
The existing default domain power down governor function for PM
domains, default_power_down_ok(), is supposed to check whether or not
the PM QoS latency constraints of the devices in the domain will be
violated if the domain is turned off by pm_genpd_poweroff().
However, the computations carried out by it don't reflect the
definition of the PM QoS latency constrait in
Documentation/ABI/testing/sysfs-devices-power.

Make default_power_down_ok() follow the definition of the PM QoS
latency constrait.  In particular, make it only take latencies into
account, because it doesn't matter how much time has elapsed since
the domain's devices were suspended for the computation.

Remove the break_even_ns and power_off_time fields from
struct generic_pm_domain, because they are not necessary any more.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-01 21:28:15 +02:00
Rafael J. Wysocki
a5bef810ad PM / Domains: Rework default device stop governor function, v2
The existing default device stop governor function for PM domains,
default_stop_ok(), is supposed to check whether or not the device's
PM QoS latency constraint will be violated if the device is stopped
by pm_genpd_runtime_suspend().  However, the computations carried out
by it don't reflect the definition of the PM QoS latency constrait in
Documentation/ABI/testing/sysfs-devices-power.

Make default_stop_ok() follow the definition of the PM QoS latency
constrait.  In particular, make it take the device's start and stop
latencies correctly.

Add a new field, effective_constraint_ns, to struct gpd_timing_data
and use it to store the difference between the device's PM QoS
constraint and its resume latency for use by the device's parent
(the effective_constraint_ns values for the children are used for
computing the parent's one along with its PM QoS constraint).

Remove the break_even_ns field from struct gpd_timing_data, because
it's not used any more.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-01 21:28:03 +02:00
Rafael J. Wysocki
e59a8db8d9 PM / Domains: Skip governor functions for CONFIG_PM_RUNTIME unset
The governor functions in drivers/base/power/domain_governor.c
are only used if CONFIG_PM_RUNTIME is set and they refer to data
structures that are only present in that case.  For this reason,
they shouldn't be compiled at all when CONFIG_PM_RUNTIME is not set.

Reported-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-14 00:39:36 +01:00
Mark Brown
925b44a273 PM / Domains: Provide an always on power domain governor
Since systems are likely to have power domains that can't be turned off
for various reasons at least temporarily while implementing power domain
support provide a default governor which will always refuse to power off
the domain, saving platforms having to implement their own.

Since the code is so tiny don't bother with a Kconfig symbol for it.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-09 23:22:41 +01:00
Rafael J. Wysocki
221e9b5838 PM / Domains: Add default power off governor function (v4)
Add a function deciding whether or not a given PM domain should
be powered off on the basis of the PM QoS constraints of devices
belonging to it and their PM QoS timing data.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-01 21:47:58 +01:00
Rafael J. Wysocki
b02c999ac3 PM / Domains: Add device stop governor function (v4)
Add a function deciding whether or not devices should be stopped in
pm_genpd_runtime_suspend() depending on their PM QoS constraints
and stop/start timing values.  Make it possible to add information
used by this function to device objects.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
2011-12-01 21:47:40 +01:00