This extends the sysfs interface for thermal cooling devices and exposes
some pretty useful statistics. These statistics have proven to be quite
useful specially while doing benchmarks related to the task scheduler,
where we want to make sure that nothing has disrupted the test,
specially the cooling device which may have put constraints on the CPUs.
The information exposed here tells us to what extent the CPUs were
constrained by the thermal framework.
The write-only "reset" file is used to reset the statistics.
The read-only "time_in_state_ms" file shows the time (in msec) spent by the
device in the respective cooling states, and it prints one line per
cooling state.
The read-only "total_trans" file shows single positive integer value
showing the total number of cooling state transitions the device has
gone through since the time the cooling device is registered or the time
when statistics were reset last.
The read-only "trans_table" file shows a two dimensional matrix, where
an entry <i,j> (row i, column j) represents the number of transitions
from State_i to State_j.
This is how the directory structure looks like for a single cooling
device:
$ ls -R /sys/class/thermal/cooling_device0/
/sys/class/thermal/cooling_device0/:
cur_state max_state power stats subsystem type uevent
/sys/class/thermal/cooling_device0/power:
autosuspend_delay_ms runtime_active_time runtime_suspended_time
control runtime_status
/sys/class/thermal/cooling_device0/stats:
reset time_in_state_ms total_trans trans_table
This is tested on ARM 64-bit Hisilicon hikey620 board running Ubuntu and
ARM 64-bit Hisilicon hikey960 board running Android.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
commit 84fe2cab48 ("cpu_cooling: Drop static-power related stuff")
removed support for static-power in kernel, but it missed reflecting the
same in documentation. Remove the static power related documentation
bits as well.
Reported-by: Javi Merino <javi.merino@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
of_cpufreq_cooling_register() isn't used by anyone and so can be
removed, but then we would be left with two routines:
cpufreq_cooling_register() and of_cpufreq_power_cooling_register() that
would look odd.
Remove current implementation of of_cpufreq_cooling_register() and
rename of_cpufreq_power_cooling_register() as
of_cpufreq_cooling_register(). This simplifies lots of stuff.
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It isn't used by anyone, drop it.
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
All the callers of of_cpufreq_power_cooling_register() have almost
identical code and it makes more sense to move that code into the helper
as its all about reading DT properties.
This got rid of lot of redundant code.
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull thermal management updates from Zhang Rui:
- Fix a problem where orderly_shutdown() is called for multiple times
due to multiple critical overheating events raised in a short period
by platform thermal driver. (Keerthy)
- Introduce a backup thermal shutdown mechanism, which invokes
kernel_power_off()/emergency_restart() directly, after
orderly_shutdown() being issued for certain amount of time(specified
via Kconfig). This is useful in certain conditions that userspace may
be unable to power off the system in a clean manner and leaves the
system in a critical state, like in the middle of driver probing
phase. (Keerthy)
- Introduce a new interface in thermal devfreq_cooling code so that the
driver can provide more precise data regarding actual power to the
thermal governor every time the power budget is calculated. (Lukasz
Luba)
- Introduce BCM 2835 soc thermal driver and northstar thermal driver,
within a new sub-folder. (Rafał Miłecki)
- Introduce DA9062/61 thermal driver. (Steve Twiss)
- Remove non-DT booting on TI-SoC driver. Also add support to fetching
coefficients from DT. (Keerthy)
- Refactorf RCAR Gen3 thermal driver. (Niklas Söderlund)
- Small fix on MTK and intel-soc-dts thermal driver. (Dawei Chien,
Brian Bian)
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (25 commits)
thermal: core: Add a back up thermal shutdown mechanism
thermal: core: Allow orderly_poweroff to be called only once
Thermal: Intel SoC DTS: Change interrupt request behavior
trace: thermal: add another parameter 'power' to the tracing function
thermal: devfreq_cooling: add new interface for direct power read
thermal: devfreq_cooling: refactor code and add get_voltage function
thermal: mt8173: minor mtk_thermal.c cleanups
thermal: bcm2835: move to the broadcom subdirectory
thermal: broadcom: ns: specify myself as MODULE_AUTHOR
thermal: da9062/61: Thermal junction temperature monitoring driver
Documentation: devicetree: thermal: da9062/61 TJUNC temperature binding
thermal: broadcom: add Northstar thermal driver
dt-bindings: thermal: add support for Broadcom's Northstar thermal
thermal: bcm2835: add thermal driver for bcm2835 SoC
dt-bindings: Add thermal zone to bcm2835-thermal example
thermal: rcar_gen3_thermal: add suspend and resume support
thermal: rcar_gen3_thermal: store device match data in private structure
thermal: rcar_gen3_thermal: enable hardware interrupts for trip points
thermal: rcar_gen3_thermal: record and check number of TSCs found
thermal: rcar_gen3_thermal: check that TSC exists before memory allocation
...
orderly_poweroff is triggered when a graceful shutdown
of system is desired. This may be used in many critical states of the
kernel such as when subsystems detects conditions such as critical
temperature conditions. However, in certain conditions in system
boot up sequences like those in the middle of driver probes being
initiated, userspace will be unable to power off the system in a clean
manner and leaves the system in a critical state. In cases like these,
the /sbin/poweroff will return success (having forked off to attempt
powering off the system. However, the system overall will fail to
completely poweroff (since other modules will be probed) and the system
is still functional with no userspace (since that would have shut itself
off).
However, there is no clean way of detecting such failure of userspace
powering off the system. In such scenarios, it is necessary for a backup
workqueue to be able to force a shutdown of the system when orderly
shutdown is not successful after a configurable time period.
Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Commit feb6cd6a0f ("thermal/intel_powerclamp: stop sched tick in forced
idle") changed how idle injection accouting, so we need to update
the documentation accordingly.
This patch also expands more details on the behavior of cur_state.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reported-by: Wang, Xiaolong <xiaolong.wang@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This adds support for hardware-tracked trip points to the device tree
thermal sensor framework.
The framework supports an arbitrary number of trip points. Whenever
the current temperature is updated, the trip points immediately
below and above the current temperature are found. A .set_trips
callback is then called with the temperatures. If there is no trip
point above or below the current temperature, the passed trip
temperature will be -INT_MAX or INT_MAX respectively. In this callback,
the driver should program the hardware such that it is notified
when either of these trip points are triggered. When a trip point
is triggered, the driver should call `thermal_zone_device_update'
for the respective thermal zone. This will cause the trip points
to be updated again.
If .set_trips is not implemented, the framework behaves as before.
This patch is based on an earlier version from Mikko Perttunen
<mikko.perttunen@kapsi.fi>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: linux-pm@vger.kernel.org
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Add apis for platform thermal drivers to query for slope and offset
attributes, which might be needed for temperature calculations.
Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This patch fix a spelling typo in intel_powerclamp.txt
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
There are several places where the English in the document is syntactically
invalid, or unclear. There are also one or two factual errors.
Reviewed-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Andy Champ <andycham@amazon.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Add details of the interface devm_thermal_zone_of_sensor_register()
and devm_thermal_zone_of_sensor_unregister() in the
<thermal/sysfs-api.txt>.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Add details of the interface thermal_zone_of_sensor_register() and
thermal_zone_of_sensor_unregister() in the thermal/sysfs-api.txt.
The details describes the functionality and parameter which
are passed to these interfaces.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Add more explicitly description for unit of integral_cutoff which used
by power allocator governor.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The power allocator governor currently requires that the thermal zone
has at least two passive trip points. If there aren't, the governor
refuses to bind to the thermal zone.
This commit relaxes that requirement. Now the governor will bind to all
thermal zones regardless of how many trip points they have.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
The Linux thermal framework support to change thermal governor
policy in userspace, but it can't show what available policies
supported.
This patch adds available_policies attribute to the thermal
framework, it can list the thermal governors which can be
used for a particular zone. This attribute is read only.
Signed-off-by: Wei Ni <wni@nvidia.com>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
It is common to have a linear extrapolation from
the current sensor readings and the actual temperature
value. This is specially the case when the sensor
is in use to extrapolate hotspots.
This patch adds slope and offset constants for
single sensor linear extrapolation equation. Because
the same sensor can be use in different locations,
from board to board, these constants are added
as part of thermal_zone_params.
The constants are available through sysfs.
It is up to the device driver to determine
the usage of these values.
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
It's useful for tuning to be able to edit thermal_zone_parameters from
userspace. Export them to the thermal_zone sysfs so that they can be
easily changed.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
The power allocator governor is a thermal governor that controls system
and device power allocation to control temperature. Conceptually, the
implementation divides the sustainable power of a thermal zone among
all the heat sources in that zone.
This governor relies on "power actors", entities that represent heat
sources. They can report current and maximum power consumption and
can set a given maximum power consumption, usually via a cooling
device.
The governor uses a Proportional Integral Derivative (PID) controller
driven by the temperature of the thermal zone. The output of the
controller is a power budget that is then allocated to each power
actor that can have bearing on the temperature we are trying to
control. It decides how much power to give each cooling device based
on the performance they are requesting. The PID controller ensures
that the total power budget does not exceed the control temperature.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Add a basic power model to the cpu cooling device to implement the
power cooling device API. The power model uses the current frequency,
current load and OPPs for the power calculations. The cpus must have
registered their OPPs using the OPP library.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Kapileshwar Singh <kapileshwar.singh@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
The fair share governor has the concept of weights, which is the
influence of each cooling device in a thermal zone. The current
implementation forces the weights of all cooling devices in a thermal
zone to add up to a 100. This complicates setups, as you need to know
in advance how many cooling devices you are going to have. If you bind a
new cooling device, you have to modify all the other cooling devices
weights, which is error prone. Furthermore, you can't specify a
"default" weight for platforms since that default value depends on the
number of cooling devices in the platform.
This patch generalizes the concept of weight by allowing any number to
be a "weight". Weights are now relative to each other. Platforms that
don't specify weights get the same default value for all their cooling
devices, so all their cdevs are considered to be equally influential.
It's important to note that previous users of the weights don't need to
alter the code: percentages continue to work as they used to. This
patch just removes the constraint of all the weights in a thermal zone
having to add up to a 100. If they do, you get the same behavior as
before. If they don't, fair share now works for that platform.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Durgadoss R <durgadoss.r@intel.com>
Acked-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
It's useful to have access to the weights for the cooling devices for
thermal zones and change them if needed. Export them to sysfs.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Currently you can specify the weight of the cooling device in the device
tree but that information is not populated to the
thermal_bind_params where the fair share governor expects it to
be. The of thermal zone device doesn't have a thermal_bind_params
structure and arguably it's better to pass the weight inside the
thermal_instance as it is specific to the bind of a cooling device to a
thermal zone parameter.
Core thermal code is fixed to populate the weight in the instance from
the thermal_bind_params, so platform code that was passing the weight
inside the thermal_bind_params continue to work seamlessly.
While we are at it, create a default value for the weight parameter for
those thermal zones that currently don't define it and remove the
hardcoded default in of-thermal.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Peter Feuerer <peter@piie.net>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Kapileshwar Singh <kapileshwar.singh@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Commit 39d99cff76 ("thermal: cpu_cooling: introduce
of_cpufreq_cooling_register") taught the cpu cooling device to register
devices that were linked to the device tree but didn't update the
cpu-cooling-api documentation. Fix it.
Cc: Amit Daniel Kachhap <amit.kachhap@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Changes:
- Change the maintainer's address (the labri address will expire soon);
- Drop the note about not all families supporting all fan modes;
- Add a note about the reported RPM not being accurate when driven outside
the vbios-defined PWM range.
Signed-off-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
When registering a thermal zone device using platform information
via bind_params, the thermal framework will always perform the
cdev binding using the lowest and highest limits (THERMAL_NO_LIMIT).
This patch changes the data structures so that it is possible
to inform what are the desired limits for each trip point
inside a bind_param. The way the binding is performed is also
changed so that it uses the new data structure.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
When registering a new thermal_device, the thermal framework
will always add a hwmon sysfs interface.
This patch adds a flag to make this behavior optional. Now
when registering a new thermal device, the caller can
optionally inform if hwmon interface is desirable. This can
be done by means of passing a thermal_zone_params.no_hwmon == true.
In order to keep same behavior as of today, all current
calls will by default create the hwmon interface.
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-acpi@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: Zhang Rui <rui.zhang@intel.com>
Suggested-by: Wei Ni <wni@nvidia.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
This patch updates the documentation to explain the driver model
and file layout.
Acked-by: Jonghwa Lee <jonghwa3.lee@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Pull thermal management updates from Zhang Rui:
"There are not too many changes this time, except two new platform
thermal drivers, ti-soc-thermal driver and x86_pkg_temp_thermal
driver, and a couple of small fixes.
Highlights:
- move the ti-soc-thermal driver out of the staging tree to the
thermal tree.
- introduce the x86_pkg_temp_thermal driver. This driver registers
CPU digital temperature package level sensor as a thermal zone.
- small fixes/cleanups including removing redundant use of
platform_set_drvdata() and of_match_ptr for all platform thermal
drivers"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (34 commits)
thermal: cpu_cooling: fix stub function
thermal: ti-soc-thermal: use standard GPIO DT bindings
thermal: MAINTAINERS: Add git tree path for SoC specific updates
thermal: fix x86_pkg_temp_thermal.c build and Kconfig
Thermal: Documentation for x86 package temperature thermal driver
Thermal: CPU Package temperature thermal
thermal: consider emul_temperature while computing trend
thermal: ti-soc-thermal: add DT example for DRA752 chip
thermal: ti-soc-thermal: add dra752 chip to device table
thermal: ti-soc-thermal: add thermal data for DRA752 chips
thermal: ti-soc-thermal: remove usage of IS_ERR_OR_NULL
thermal: ti-soc-thermal: freeze FSM while computing trend
thermal: ti-soc-thermal: remove external heat while extrapolating hotspot
thermal: ti-soc-thermal: update DT reference for OMAP5430
x86, mcheck, therm_throt: Process package thresholds
thermal: cpu_cooling: fix 'descend' check in get_property()
Thermal: spear: Remove redundant use of of_match_ptr
Thermal: kirkwood: Remove redundant use of of_match_ptr
Thermal: dove: Remove redundant use of of_match_ptr
Thermal: armada: Remove redundant use of of_match_ptr
...
Added documentation describing details of the x86 package temperature
thermal driver.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
To follow the prefix names used by the thermal functions,
this patch renames notify_thermal_framework to thermal_notify_framework.
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
The thermal governors are part of the thermal framework,
rather than a seperate feature/module.
Because the generic thermal layer can not work without
thermal governors, and it must load the thermal governors
during its initialization.
Build them into one module in this patch.
This also fix a problem that the generic thermal layer does not
work when CONFIG_THERMAL=m and CONFIG_THERMAL_GOV_XXX=y.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>
Acked-by: Durgadoss R <durgadoss.r@intel.com>
Because this feature is for debuging purposes, it is highly
recommended to do not enable this on production systems.
This patch adds warnings for system integrators, so that
people are aware of this potential security issue.
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This removes the driver specific sysfs support of the temperature
emulation and uses the newly added core thermal framework for thermal
emulation. An exynos platform specific handler is added to support this.
In this patch, the exynos senor(tmu) related code and exynos framework
related (thermal zone, cooling devices) code are intentionally kept separate.
So an emulated function pointer is passed from sensor to framework. This is
beneficial in adding more sensor support using the same framework code
which is an ongoing work. The goal is to finally split them totally. Even
the existing read_temperature also follows the same execution method.
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Pull thermal management updates from Zhang Rui:
"Highlights:
- introduction of Dove thermal sensor driver.
- introduction of Kirkwood thermal sensor driver.
- introduction of intel_powerclamp thermal cooling device driver.
- add interrupt and DT support for rcar thermal driver.
- add thermal emulation support which allows platform thermal driver
to do software/hardware emulation for thermal issues."
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (36 commits)
thermal: rcar: remove __devinitconst
thermal: return an error on failure to register thermal class
Thermal: rename thermal governor Kconfig option to avoid generic naming
thermal: exynos: Use the new thermal trend type for quick cooling action.
Thermal: exynos: Add support for temperature falling interrupt.
Thermal: Dove: Add Themal sensor support for Dove.
thermal: Add support for the thermal sensor on Kirkwood SoCs
thermal: rcar: add Device Tree support
thermal: rcar: remove machine_power_off() from rcar_thermal_notify()
thermal: rcar: add interrupt support
thermal: rcar: add read/write functions for common/priv data
thermal: rcar: multi channel support
thermal: rcar: use mutex lock instead of spin lock
thermal: rcar: enable CPCTL to use hardware TSC deciding
thermal: rcar: use parenthesis on macro
Thermal: fix a build warning when CONFIG_THERMAL_EMULATION cleared
Thermal: fix a wrong comment
thermal: sysfs: Add a new sysfs node emul_temp for thermal emulation
PM: intel_powerclamp: off by one in start_power_clamp()
thermal: exynos: Miscellaneous fixes to support falling threshold interrupt
...
This patch adds support to set the emulated temperature method in
thermal zone (sensor). After setting this feature thermal zone may
report this temperature and not the actual temperature. The emulation
implementation may be based on sensor capability through platform
specific handler or pure software emulation if no platform handler defined.
This is useful in debugging different temperature threshold and its
associated cooling action. Critical threshold's cannot be emulated.
Writing 0 on this node should disable emulation.
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Intel PowerClamp driver performs synchronized idle injection across
all online CPUs. The goal is to maintain a given package level C-state
ratio.
Compared to other throttling methods already exist in the kernel,
such as ACPI PAD (taking CPUs offline) and clock modulation, this is often
more efficient in terms of performance per watt.
Please refer to Documentation/thermal/intel_powerclamp.txt for more details.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This patch changes the function thermal_generate_netlink_event
to receive a thermal zone device instead of a originator id.
This way, the messages will always be bound to a thermal zone.
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Reviewed-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This patch supports exynos's emulation mode with newly created sysfs node.
Exynos 4x12 (4212, 4412) and 5 series provide emulation mode for thermal
management unit. Thermal emulation mode supports software debug for TMU's
operation. User can set temperature manually with software code and TMU
will read current temperature from user value not from sensor's value.
This patch includes also documentary placed under Documentation/thermal/.
Signed-off-by: Jonghwa Lee <jonghwa3.lee@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This patch adds documentation for thermal_bind_params
and thermal_zone_params structures. Also, adds details
on EXPORT_SYMBOL APIs.
Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This movement is needed because the hwmon entries and corresponding sysfs
interface is a duplicate of utilities already provided by
driver/thermal/thermal_sys.c. The goal is to place it in thermal folder
and add necessary functions to use the in-kernel thermal interfaces.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: SangWook Ju <sw.ju@samsung.com>
Cc: Durgadoss <durgadoss.r@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This patchset introduces a new generic cooling device based on cpufreq
that can be used on non-ACPI platforms. As a proof of concept, we have
drivers for the following platforms using this mechanism now:
* Samsung Exynos (Exynos4 and Exynos5) in the current patchset.
* Freescale i.MX (git://git.linaro.org/people/amitdanielk/linux.git imx6q_thermal)
There is a small change in cpufreq cooling registration APIs, so a minor
change is needed for Freescale platforms.
Brief Description:
1) The generic cooling devices code is placed inside driver/thermal/*
as placing inside acpi folder will need un-necessary enabling of acpi
code. This code is architecture independent.
2) This patchset adds generic cpu cooling low level implementation
through frequency clipping. In future, other cpu related cooling
devices may be added here. An ACPI version of this already exists
(drivers/acpi/processor_thermal.c) .But this will be useful for
platforms like ARM using the generic thermal interface along with the
generic cpu cooling devices. The cooling device registration API's
return cooling device pointers which can be easily binded with the
thermal zone trip points. The important APIs exposed are,
a) struct thermal_cooling_device *cpufreq_cooling_register(
struct cpumask *clip_cpus)
b) void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
3) Samsung exynos platform thermal implementation is done using the
generic cpu cooling APIs and the new trip type. The temperature sensor
driver present in the hwmon folder(registered as hwmon driver) is moved
to thermal folder and registered as a thermal driver.
A simple data/control flow diagrams is shown below,
Core Linux thermal <-----> Exynos thermal interface <----- Temperature Sensor
| |
\|/ |
Cpufreq cooling device <---------------
TODO:
*Will send the DT enablement patches later after the driver is merged.
This patch:
Add support for generic cpu thermal cooling low level implementations
using frequency scaling up/down based on the registration parameters.
Different cpu related cooling devices can be registered by the user and
the binding of these cooling devices to the corresponding trip points can
be easily done as the registration APIs return the cooling device pointer.
The user of these APIs are responsible for passing clipping frequency .
The drivers can also register to recieve notification about any cooling
action called.
[akpm@linux-foundation.org: fix comment layout]
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: SangWook Ju <sw.ju@samsung.com>
Cc: Durgadoss <durgadoss.r@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
set upper and lower limits when binding
a thermal cooling device to a thermal zone device.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Eduardo Valentin <eduardo.valentin@ti.com>
With commit 6503e5df08,
the value of /sys/class/thermal/thermal_zoneX/mode has been changed
from user/kernel to enabled/disabled.
Update the documentation so that users won't be confused.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
