The cpu idle cooling device offers a new method to cool down a CPU by
injecting idle cycles at runtime.
It has some similarities with the intel power clamp driver but it is
actually designed to be more generic and relying on the idle injection
powercap framework.
The idle injection duration is fixed while the running duration is
variable. That allows to have control on the device reactivity for the
user experience.
An idle state powering down the CPU or the cluster will allow to drop
the static leakage, thus restoring the heat capacity of the SoC. It
can be set with a trip point between the hot and the critical points,
giving the opportunity to prevent a hard reset of the system when the
cpufreq cooling fails to cool down the CPU.
With more sophisticated boards having a per core sensor, the idle
cooling device allows to cool down a single core without throttling
the compute capacity of several cpus belonging to the same clock line,
so it could be used in collaboration with the cpufreq cooling device.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/20191219225317.17158-2-daniel.lezcano@linaro.org
The next changes will add a new way to cool down a CPU by injecting
idle cycles. With the current configuration, a CPU cooling device is
the cpufreq cooling device. As we want to add a new CPU cooling
device, let's convert the CPU cooling to a choice giving a list of CPU
cooling devices. At this point, there is obviously only one CPU
cooling device.
There is no functional changes.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/20191204153930.9128-1-daniel.lezcano@linaro.org
As the conditions are simplified and unified, it is useless to have
different blocks of definitions under the same compiler condition,
let's merge the blocks.
There is no functional change.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Link: https://lore.kernel.org/r/20191030091038.678-2-daniel.lezcano@linaro.org
The option CONFIG_CPU_THERMAL depends on CONFIG_OF in the Kconfig.
It it pointless to check if CONFIG_OF is set in the header file as
this is always true if CONFIG_CPU_THERMAL is true. Remove it.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Link: https://lore.kernel.org/r/20191030091038.678-1-daniel.lezcano@linaro.org
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license this program
is distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 59 temple place suite 330 boston ma 02111
1307 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 83 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.021731668@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
No one has used it for the last two and half years (since it was
introduced by commit c36cf07176 (thermal: cpu_cooling: implement the
power cooling device API), get rid of 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>
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>
The CPU cooling driver uses the cpufreq policy, to get clip_cpus, the
frequency table, etc. Most of the callers of CPU cooling driver's
registration routines have the cpufreq policy with them, but they only
pass the policy->related_cpus cpumask. The __cpufreq_cooling_register()
routine then gets the policy by itself and uses it.
It would be much better if the callers can pass the policy instead
directly. This also fixes a basic design flaw, where the policy can be
freed while the CPU cooling driver is still active.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
There is only one user of cpufreq_cooling_get_level() and that already
has pointer to the cpufreq_cdev structure. It can directly call
get_level() instead and we can get rid of cpufreq_cooling_get_level().
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Tested-by: Lukasz Luba <lukasz.luba@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 documentation of of_cpufreq_cooling_register() and
cpufreq_cooling_register() say that they return ERR_PTR() on error.
Accordingly, callers only check for IS_ERR(). Therefore, make them
return ERR_PTR(-ENOSYS) as is customary in the kernel when config
options are missing.
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>
This patch introduces an API to register cpufreq cooling device
based on device tree node.
The registration via device tree node differs from normal
registration due to the fact that it is needed to fill
the device_node structure in order to be able to match
the cooling devices with trip points.
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>
The function stub for cpufreq_cooling_get_level introduced
in 57df81069 "Thermal: exynos: fix cooling state translation"
is not syntactically correct C and needs to be fixed to avoid
this error:
In file included from drivers/thermal/db8500_thermal.c:20:0:
include/linux/cpu_cooling.h: In function 'cpufreq_cooling_get_level':
include/linux/cpu_cooling.h:57:1:
error: parameter name omitted unsigned long cpufreq_cooling_get_level(unsigned int, unsigned int) ^
include/linux/cpu_cooling.h:57:1: error: parameter name omitted
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Amit Daniel kachhap <amit.daniel@samsung.com>
Cc: stable@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
To improve code readiness, change the way the lines
are broken in this file.
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Remove defines that are not in used.
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Acked-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Update header list for cpu_cooling.h. Missing definition of cpumask.
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Acked-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
As thermal drivers can be built as modules and also
the thermal framework itself, building cpu cooling
only as built-in can cause linking errors. For instance:
* Generic Thermal sysfs driver
*
Generic Thermal sysfs driver (THERMAL) [M/n/y/?] m
generic cpu cooling support (CPU_THERMAL) [N/y/?] (NEW) y
with the following drive:
CONFIG_OMAP_BANDGAP=m
generates:
ERROR: "cpufreq_cooling_unregister" [drivers/staging/omap-thermal/omap-thermal.ko] undefined!
ERROR: "cpufreq_cooling_register" [drivers/staging/omap-thermal/omap-thermal.ko] undefined!
This patch changes cpu cooling driver to allow it
to be built as module.
Reported-by: Enric Balletbo i Serra <eballetbo@gmail.com>
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>
There are predefined cpu_masks that are const data structures.
This patch changes the cpu cooling register function so that
those const cpu_masks can be used, without compilation warnings.
include/linux/cpumask.h
* The following particular system cpumasks and operations manage
* possible, present, active and online cpus.
*
* cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
* cpu_present_mask - has bit 'cpu' set iff cpu is populated
* cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler
* cpu_active_mask - has bit 'cpu' set iff cpu available to migration
*
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.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>
