Re: [PATCH RESEND] thermal: add generic cpufreq cooling implementation
Hello Rui and Amit, On Mon, Sep 10, 2012 at 9:25 AM, Zhang Rui rui.zh...@intel.com wrote: Refreshed to remove the notifier mechanism as we do not have a real user of it. if there is no problem, I'll apply the whole patch set to thermal next tree. From: Amit Daniel Kachhap amit.kach...@linaro.org Date: Thu, 16 Aug 2012 17:11:40 +0530 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. Cc: Guenter Roeck guenter.ro...@ericsson.com Cc: SangWook Ju sw...@samsung.com Cc: Durgadoss durgados...@intel.com Cc: Len Brown l...@kernel.org Cc: Jean Delvare kh...@linux-fr.org Cc: Kyungmin Park kmp...@infradead.org Cc: Kukjin Kim kgene@samsung.com Signed-off-by: Zhang Rui rui.zh...@intel.com Signed-off-by: Andrew Morton a...@linux-foundation.org Signed-off-by: Amit Daniel Kachhap amit.dan...@samsung.com can you please include my Reviewed-by? Also on your patch series I have reviewed. Reviewed-by: Eduardo Valentin eduardo.valen...@ti.com --- Documentation/thermal/cpu-cooling-api.txt | 33 ++ drivers/thermal/Kconfig | 11 + drivers/thermal/Makefile |1 + drivers/thermal/cpu_cooling.c | 450 + include/linux/cpu_cooling.h | 58 5 files changed, 553 insertions(+), 0 deletions(-) create mode 100644 Documentation/thermal/cpu-cooling-api.txt create mode 100644 drivers/thermal/cpu_cooling.c create mode 100644 include/linux/cpu_cooling.h diff --git a/Documentation/thermal/cpu-cooling-api.txt b/Documentation/thermal/cpu-cooling-api.txt new file mode 100644 index 000..6fe9cdb --- /dev/null +++ b/Documentation/thermal/cpu-cooling-api.txt @@ -0,0 +1,33 @@ +CPU cooling APIs How To +=== + +Written by Amit Daniel Kachhap amit.kach...@linaro.org + +Updated: 12 May 2012 + +Copyright (c) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) + +0. Introduction + +The generic cpu cooling(freq clipping) provides registration/unregistration APIs +to the caller. The binding of the cooling devices to the trip point is left for +the user. The registration APIs returns the cooling device pointer. + +1. cpu cooling APIs + +1.1 cpufreq registration/unregistration APIs +1.1.1 struct thermal_cooling_device *cpufreq_cooling_register( + struct cpumask *clip_cpus) + +This interface function registers the cpufreq cooling device
Re: [PATCH v6 1/6] thermal: add generic cpufreq cooling implementation
Hello Rui, On Mon, Aug 20, 2012 at 5:16 AM, Zhang Rui rui.zh...@intel.com wrote: On 五, 2012-08-17 at 11:56 +0300, Valentin, Eduardo wrote: Hello, + + +1.2 CPU cooling action notifier register/unregister interface +1.2.1 int cputherm_register_notifier(struct notifier_block *nb, + unsigned int list) + +This interface registers a driver with cpu cooling layer. The driver will +be notified when any cpu cooling action is called. + +nb: notifier function to register +list: CPUFREQ_COOLING_START or CPUFREQ_COOLING_STOP + +1.2.2 int cputherm_unregister_notifier(struct notifier_block *nb, + unsigned int list) + +This interface registers a driver with cpu cooling layer. The driver will +be notified when any cpu cooling action is called. + +nb: notifier function to register +list: CPUFREQ_COOLING_START or CPUFREQ_COOLING_STOP what are these two APIs used for? I did not see they are used in your patch set, do I miss something? No currently they are not used by my patches. I added them on request from Eduardo and others Yeah, this was a suggestion as we didn't really know how the FW part would evolve by that time. The reasoning is to allow any interested user (in kernel) to be notified when max frequency changes. in this case, the cooling device should be updated. Say all the target of the thermal_instances of a cooling devices is 0, which means they want the cpu to run at maximum frequency, when the max frequency changes, we should set the processor to the new max frequency as well. Using notification is not a good idea as user can not handle this without interacting with the thermal framework. IMO, we should introduce a new API to handle this, rather than just notifications to users. Agreed. The context is actually much wider than the CPU cooling. In fact, cooling co-processors is actually where things gets a bit complicated. The idea behind this type of handshaking is to allow the affected subsystem to change their actual setup when max performance is not allowed anymore. Actually, the use case behind this is to allow such users to perform some handshaking or stop their activities or even change some paramenters, in case the max frequency would change. It is the cooling device driver that notice this change first, and it should invoke something like thermal_cooling_device_update/rebind() to tell the thermal framework this change. Yeah. Ideally, the framework needs to be aware of cooling device state change. Today, as we have pretty much a broadcast/unidirectional type of messaging, the framework/policy always assumes the cooling devices will be in sync with what it is dictated by the policy. Ideally it would be possible to nack the cooling transition. But that is yet a wider discussion. So far we don't have users for this. yep. I thought about this before, but I'd prefer to do this when there is a real user. Or else, we are kind of over-designing here. how about removing this piece of code for now? Agreed. I second you that this problem is a much wider issue and needs improvement in the FW itself and how the cooling devices are designed. thanks, rui diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 7dd8c34..996003b 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -19,6 +19,17 @@ config THERMAL_HWMON depends on HWMON=y || HWMON=THERMAL default y +config CPU_THERMAL + bool generic cpu cooling support + depends on THERMAL CPU_FREQ + help + This implements the generic cpu cooling mechanism through frequency + reduction, cpu hotplug and any other ways of reducing temperature. An + ACPI version of this already exists(drivers/acpi/processor_thermal.c). + This will be useful for platforms using the generic thermal interface + and not the ACPI interface. + If you want this support, you should say Y here. + config SPEAR_THERMAL bool SPEAr thermal sensor driver depends on THERMAL diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index fd9369a..aae59ad 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -3,5 +3,6 @@ # obj-$(CONFIG_THERMAL)+= thermal_sys.o +obj-$(CONFIG_CPU_THERMAL)+= cpu_cooling.o obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o obj-$(CONFIG_RCAR_THERMAL) += rcar_thermal.o diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c new file mode 100644 index 000..c42e557 --- /dev/null +++ b/drivers/thermal/cpu_cooling.c @@ -0,0 +1,512 @@ +/* + * linux/drivers/thermal/cpu_cooling.c + * + * Copyright (C) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) + * Copyright (C) 2012 Amit Daniel amit.kach...@linaro.org
Re: [PATCH v6 1/6] thermal: add generic cpufreq cooling implementation
Hello, On Fri, Aug 17, 2012 at 10:58 AM, Amit Kachhap amit.kach...@linaro.org wrote: On 17 August 2012 12:54, Zhang Rui rui.zh...@intel.com wrote: On 四, 2012-08-16 at 17:11 +0530, Amit Daniel Kachhap wrote: 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. [a...@linux-foundation.org: fix comment layout] Signed-off-by: Amit Daniel Kachhap amit.kach...@linaro.org Cc: Guenter Roeck guenter.ro...@ericsson.com Cc: SangWook Ju sw...@samsung.com Cc: Durgadoss durgados...@intel.com Cc: Len Brown l...@kernel.org Cc: Jean Delvare kh...@linux-fr.org Cc: Kyungmin Park kmp...@infradead.org Cc: Kukjin Kim kgene@samsung.com Signed-off-by: Andrew Morton a...@linux-foundation.org Signed-off-by: Amit Daniel Kachhap amit.dan...@samsung.com --- Documentation/thermal/cpu-cooling-api.txt | 52 +++ drivers/thermal/Kconfig | 11 + drivers/thermal/Makefile |1 + drivers/thermal/cpu_cooling.c | 512 + include/linux/cpu_cooling.h | 79 + 5 files changed, 655 insertions(+), 0 deletions(-) create mode 100644 Documentation/thermal/cpu-cooling-api.txt create mode 100644 drivers/thermal/cpu_cooling.c create mode 100644 include/linux/cpu_cooling.h diff --git a/Documentation/thermal/cpu-cooling-api.txt b/Documentation/thermal/cpu-cooling-api.txt new file mode 100644 index 000..a1f2a6b --- /dev/null +++ b/Documentation/thermal/cpu-cooling-api.txt @@ -0,0 +1,52 @@ +CPU cooling APIs How To +=== + +Written by Amit Daniel Kachhap amit.kach...@linaro.org + +Updated: 12 May 2012 + +Copyright (c) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) + +0. Introduction + +The generic cpu cooling(freq clipping) provides registration/unregistration APIs +to the caller. The binding of the cooling devices to the trip point is left for +the user. The registration APIs returns the cooling device pointer. + +1. cpu cooling APIs + +1.1 cpufreq registration/unregistration APIs +1.1.1 struct thermal_cooling_device *cpufreq_cooling_register( + struct cpumask *clip_cpus) + +This interface function registers the cpufreq cooling device with the name +thermal-cpufreq-%x. This api can support multiple instances of cpufreq +cooling devices. + + clip_cpus: cpumask of cpus where the frequency constraints will happen. + +1.1.2 void
Re: [linux-pm] [PATCH v6 1/6] thermal: add generic cpufreq cooling implementation
Amit, Thanks again for keeping this up. On Thu, Aug 16, 2012 at 2:41 PM, Amit Daniel Kachhap amit.kach...@linaro.org wrote: 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) FYI, the OMAP code is under drivers/staging/omap-thermal/. The file omap-thermal-common.c is the one which is using your generic cooling device. But it needs to be updated accordingly to the API change you mention. 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. [a...@linux-foundation.org: fix comment layout] Signed-off-by: Amit Daniel Kachhap amit.kach...@linaro.org Cc: Guenter Roeck guenter.ro...@ericsson.com Cc: SangWook Ju sw...@samsung.com Cc: Durgadoss durgados...@intel.com Cc: Len Brown l...@kernel.org Cc: Jean Delvare kh...@linux-fr.org Cc: Kyungmin Park kmp...@infradead.org Cc: Kukjin Kim kgene@samsung.com Signed-off-by: Andrew Morton a...@linux-foundation.org Signed-off-by: Amit Daniel Kachhap amit.dan...@samsung.com Reviewed-by: Eduardo Valentin eduardo.valen...@ti.com --- Documentation/thermal/cpu-cooling-api.txt | 52 +++ drivers/thermal/Kconfig | 11 + drivers/thermal/Makefile |1 + drivers/thermal/cpu_cooling.c | 512 + include/linux/cpu_cooling.h | 79 + 5 files changed, 655 insertions(+), 0 deletions(-) create mode 100644 Documentation/thermal/cpu-cooling-api.txt create mode 100644 drivers/thermal/cpu_cooling.c create mode 100644 include/linux/cpu_cooling.h diff --git a/Documentation/thermal/cpu-cooling-api.txt b/Documentation/thermal/cpu-cooling-api.txt new file mode 100644 index 000..a1f2a6b --- /dev/null +++ b/Documentation/thermal/cpu-cooling-api.txt @@ -0,0 +1,52 @@ +CPU cooling APIs How To +=== + +Written by Amit Daniel Kachhap amit.kach...@linaro.org + +Updated: 12 May 2012 + +Copyright (c) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) + +0. Introduction + +The generic cpu cooling(freq clipping) provides registration/unregistration APIs +to the caller. The binding of the cooling devices to the trip point is left for +the user. The registration APIs returns the cooling device pointer. + +1. cpu cooling APIs + +1.1 cpufreq registration/unregistration APIs +1.1.1 struct thermal_cooling_device *cpufreq_cooling_register( + struct cpumask *clip_cpus) + +This interface function registers the cpufreq cooling device with the name +
Re: [linux-pm] [RESEND PATCH v4 1/5] thermal: add generic cpufreq cooling implementation
Amit, On Thu, Jul 12, 2012 at 4:41 PM, Amit Daniel Kachhap amit.kach...@linaro.org wrote: 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. * TI OMAP (git://git.linaro.org/people/amitdanielk/linux.git omap4460_thermal) FYI, I have rewriten the OMAP BG driver and currently trying to push it to staging area. It should now support more omap versions. I will readapt the cpu cooling based on this patch. I am keeping the reworked driver here: g...@gitorious.org:thermal-framework/thermal-framework.git thermal_work/omap/bandgap_staging * 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 OMAP and 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 codes 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 freq_clip_table *tab_ptr, unsigned int tab_size) 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. [a...@linux-foundation.org: fix comment layout] Signed-off-by: Amit Daniel Kachhap amit.kach...@linaro.org Cc: Donggeun Kim dg77@samsung.com Cc: Guenter Roeck guenter.ro...@ericsson.com Cc: SangWook Ju sw...@samsung.com Cc: Durgadoss durgados...@intel.com Cc: Len Brown l...@kernel.org Cc: Jean Delvare kh...@linux-fr.org Signed-off-by: Andrew Morton a...@linux-foundation.org --- Documentation/thermal/cpu-cooling-api.txt | 60 drivers/thermal/Kconfig | 11 + drivers/thermal/Makefile |3 +- drivers/thermal/cpu_cooling.c | 483 + include/linux/cpu_cooling.h | 99 ++ 5 files changed, 655 insertions(+), 1 deletions(-) create mode 100644 Documentation/thermal/cpu-cooling-api.txt create mode 100644 drivers/thermal/cpu_cooling.c create mode 100644 include/linux/cpu_cooling.h diff --git a/Documentation/thermal/cpu-cooling-api.txt b/Documentation/thermal/cpu-cooling-api.txt new file mode 100644 index 000..557adb8 --- /dev/null +++ b/Documentation/thermal/cpu-cooling-api.txt @@ -0,0 +1,60 @@ +CPU cooling APIs How To +=== + +Written by Amit Daniel Kachhap amit.kach...@linaro.org + +Updated: 12 May 2012 + +Copyright (c) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) + +0. Introduction + +The generic cpu cooling(freq clipping, cpuhotplug etc) provides +registration/unregistration APIs to the caller. The binding of the cooling +devices to the trip point is left for the user. The registration APIs returns +the cooling device pointer. + +1. cpu cooling APIs + +1.1 cpufreq registration/unregistration APIs +1.1.1 struct thermal_cooling_device *cpufreq_cooling_register( + struct freq_clip_table *tab_ptr, unsigned int tab_size) + +This
Re: [PATCH v4 1/5] thermal: Add generic cpufreq cooling implementation
Hey Rob and Amit, On Tue, Jun 26, 2012 at 6:12 AM, Rob Lee rob@linaro.org wrote: Hey Amit, I was just re-organizing the imx thermal driver that uses this cpu cooling interface and noticed a couple of small issues here. If While rewriting the OMAP BG driver on top of this series I noticed similar issues. Apart from those pointed by Rob, I have another minor fix. these suggestions are agreed upon and if it's too late for these issues be changed with this patchset, I can submit them separately unless you'd prefer to. On Sat, May 12, 2012 at 4:40 AM, Amit Daniel Kachhap amit.kach...@linaro.org wrote: This patch adds 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. Signed-off-by: Amit Daniel Kachhap amit.kach...@linaro.org --- Documentation/thermal/cpu-cooling-api.txt | 60 drivers/thermal/Kconfig | 11 + drivers/thermal/Makefile | 3 +- drivers/thermal/cpu_cooling.c | 483 + include/linux/cpu_cooling.h | 99 ++ 5 files changed, 655 insertions(+), 1 deletions(-) create mode 100644 Documentation/thermal/cpu-cooling-api.txt create mode 100644 drivers/thermal/cpu_cooling.c create mode 100644 include/linux/cpu_cooling.h diff --git a/Documentation/thermal/cpu-cooling-api.txt b/Documentation/thermal/cpu-cooling-api.txt new file mode 100644 index 000..557adb8 --- /dev/null +++ b/Documentation/thermal/cpu-cooling-api.txt @@ -0,0 +1,60 @@ +CPU cooling APIs How To +=== + +Written by Amit Daniel Kachhap amit.kach...@linaro.org + +Updated: 12 May 2012 + +Copyright (c) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) + +0. Introduction + +The generic cpu cooling(freq clipping, cpuhotplug etc) provides +registration/unregistration APIs to the caller. The binding of the cooling +devices to the trip point is left for the user. The registration APIs returns +the cooling device pointer. + +1. cpu cooling APIs + +1.1 cpufreq registration/unregistration APIs +1.1.1 struct thermal_cooling_device *cpufreq_cooling_register( + struct freq_clip_table *tab_ptr, unsigned int tab_size) + + This interface function registers the cpufreq cooling device with the name + thermal-cpufreq-%x. This api can support multiple instances of cpufreq + cooling devices. + + tab_ptr: The table containing the maximum value of frequency to be clipped + for each cooling state. + .freq_clip_max: Value of frequency to be clipped for each allowed + cpus. + .temp_level: Temperature level at which the frequency clamping will + happen. + .mask_val: cpumask of the allowed cpu's + tab_size: the total number of cpufreq cooling states. + +1.1.2 void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) + + This interface function unregisters the thermal-cpufreq-%x cooling device. + + cdev: Cooling device pointer which has to be unregistered. + + +1.2 CPU cooling action notifier register/unregister interface +1.2.1 int cputherm_register_notifier(struct notifier_block *nb, + unsigned int list) + + This interface registers a driver with cpu cooling layer. The driver will + be notified when any cpu cooling action is called. + + nb: notifier function to register + list: CPUFREQ_COOLING_START or CPUFREQ_COOLING_STOP + +1.2.2 int cputherm_unregister_notifier(struct notifier_block *nb, + unsigned int list) + + This interface registers a driver with cpu cooling layer. The driver will + be notified when any cpu cooling action is called. + + nb: notifier function to register + list: CPUFREQ_COOLING_START or CPUFREQ_COOLING_STOP diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 514a691..d9c529f 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -19,6 +19,17 @@ config THERMAL_HWMON depends on HWMON=y || HWMON=THERMAL default y +config CPU_THERMAL Perhaps the name CPU_COOLING or CPUFREQ_COOLING would more accurately describe this functionality? I like the latter since now this mechanism only supports cooling by using cpufreq. + bool generic cpu cooling support If we use CPUFREQ_COOLING, then perhaps this could say: bool cpu cooling through cpufreq frequency limiting + depends on THERMAL CPU_FREQ + help + This implements the generic cpu cooling
