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kernel-fxtec-pro1x/include/linux/pm_domain.h

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PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
/*
* pm_domain.h - Definitions and headers related to device power domains.
*
* Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
*
* This file is released under the GPLv2.
*/
#ifndef _LINUX_PM_DOMAIN_H
#define _LINUX_PM_DOMAIN_H
#include <linux/device.h>
device.h: audit and cleanup users in main include dir The <linux/device.h> header includes a lot of stuff, and it in turn gets a lot of use just for the basic "struct device" which appears so often. Clean up the users as follows: 1) For those headers only needing "struct device" as a pointer in fcn args, replace the include with exactly that. 2) For headers not really using anything from device.h, simply delete the include altogether. 3) For headers relying on getting device.h implicitly before being included themselves, now explicitly include device.h 4) For files in which doing #1 or #2 uncovers an implicit dependency on some other header, fix by explicitly adding the required header(s). Any C files that were implicitly relying on device.h to be present have already been dealt with in advance. Total removals from #1 and #2: 51. Total additions coming from #3: 9. Total other implicit dependencies from #4: 7. As of 3.3-rc1, there were 110, so a net removal of 42 gives about a 38% reduction in device.h presence in include/* Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-01-30 09:46:54 -07:00
#include <linux/mutex.h>
#include <linux/pm.h>
PM / Domains: fix compilation failure for CONFIG_PM_GENERIC_DOMAINS unset Fix the following compalitaion breakage: In file included from linux/drivers/sh/pm_runtime.c:15: linux/include/linux/pm_domain.h: In function 'dev_to_genpd': linux/include/linux/pm_domain.h:142: error: implicit declaration of function 'ERR_PTR' linux/include/linux/pm_domain.h:142: warning: return makes pointer from integer without a cast In file included from linux/include/linux/sh_clk.h:10, from linux/drivers/sh/pm_runtime.c:19: linux/include/linux/err.h: At top level: linux/include/linux/err.h:22: error: conflicting types for 'ERR_PTR' linux/include/linux/pm_domain.h:142: note: previous implicit declaration of 'ERR_PTR' was here make[3]: *** [drivers/sh/pm_runtime.o] Error 1 Reported-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-30 16:05:31 -07:00
#include <linux/err.h>
PM / Domains: Add OF support A device node pointer is added to generic pm domain structure to associate the domain with a node in the device tree. The platform code parses the device tree to find available nodes representing the generic power domain, instantiates the available domains and initializes them by calling pm_genpd_init(). Nodes representing the devices include a phandle of the power domain to which it belongs. As these devices get instantiated, the driver code checkes for availability of a power domain phandle, converts the phandle to a device node and uses the new pm_genpd_of_add_device() api to associate the device with a power domain. pm_genpd_of_add_device() runs through its list of registered power domains and matches the OF node of the domain with the one specified as the parameter. If a match is found, the device is associated with the matched domain. Cc: Rob Herring <rob.herring@calxeda.com> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-01-26 23:22:07 -07:00
#include <linux/of.h>
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>
2012-05-01 13:34:07 -06:00
#include <linux/notifier.h>
PM / Domains: Add preliminary support for cpuidle, v2 On some systems there are CPU cores located in the same power domains as I/O devices. Then, power can only be removed from the domain if all I/O devices in it are not in use and the CPU core is idle. Add preliminary support for that to the generic PM domains framework. First, the platform is expected to provide a cpuidle driver with one extra state designated for use with the generic PM domains code. This state should be initially disabled and its exit_latency value should be set to whatever time is needed to bring up the CPU core itself after restoring power to it, not including the domain's power on latency. Its .enter() callback should point to a procedure that will remove power from the domain containing the CPU core at the end of the CPU power transition. The remaining characteristics of the extra cpuidle state, referred to as the "domain" cpuidle state below, (e.g. power usage, target residency) should be populated in accordance with the properties of the hardware. Next, the platform should execute genpd_attach_cpuidle() on the PM domain containing the CPU core. That will cause the generic PM domains framework to treat that domain in a special way such that: * When all devices in the domain have been suspended and it is about to be turned off, the states of the devices will be saved, but power will not be removed from the domain. Instead, the "domain" cpuidle state will be enabled so that power can be removed from the domain when the CPU core is idle and the state has been chosen as the target by the cpuidle governor. * When the first I/O device in the domain is resumed and __pm_genpd_poweron(() is called for the first time after power has been removed from the domain, the "domain" cpuidle state will be disabled to avoid subsequent surprise power removals via cpuidle. The effective exit_latency value of the "domain" cpuidle state depends on the time needed to bring up the CPU core itself after restoring power to it as well as on the power on latency of the domain containing the CPU core. Thus the "domain" cpuidle state's exit_latency has to be recomputed every time the domain's power on latency is updated, which may happen every time power is restored to the domain, if the measured power on latency is greater than the latency stored in the corresponding generic_pm_domain structure. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-07-03 11:07:42 -06:00
#include <linux/cpuidle.h>
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
PM / Domains: Do not execute device callbacks under locks Currently, the .start_device() and .stop_device() callbacks from struct generic_pm_domain() as well as the device drivers' runtime PM callbacks used by the generic PM domains code are executed under the generic PM domain lock. This, unfortunately, is prone to deadlocks, for example if a device and its parent are boths members of the same PM domain. For this reason, it would be better if the PM domains code didn't execute device callbacks under the lock. Rework the locking in the generic PM domains code so that the lock is dropped for the execution of device callbacks. To this end, introduce PM domains states reflecting the current status of a PM domain and such that the PM domain lock cannot be acquired if the status is GPD_STATE_BUSY. Make threads attempting to acquire a PM domain's lock wait until the status changes to either GPD_STATE_ACTIVE or GPD_STATE_POWER_OFF. This change by itself doesn't fix the deadlock problem mentioned above, but the mechanism introduced by it will be used for for this purpose by a subsequent patch. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-11 16:39:29 -06:00
enum gpd_status {
GPD_STATE_ACTIVE = 0, /* PM domain is active */
PM / Domains: Rename GPD_STATE_WAIT_PARENT to GPD_STATE_WAIT_MASTER Since it is now possible for a PM domain to have multiple masters instead of one parent, rename the "wait for parent" status to reflect the new situation. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-08 15:43:50 -06:00
GPD_STATE_WAIT_MASTER, /* PM domain's master is being waited for */
PM / Domains: Do not execute device callbacks under locks Currently, the .start_device() and .stop_device() callbacks from struct generic_pm_domain() as well as the device drivers' runtime PM callbacks used by the generic PM domains code are executed under the generic PM domain lock. This, unfortunately, is prone to deadlocks, for example if a device and its parent are boths members of the same PM domain. For this reason, it would be better if the PM domains code didn't execute device callbacks under the lock. Rework the locking in the generic PM domains code so that the lock is dropped for the execution of device callbacks. To this end, introduce PM domains states reflecting the current status of a PM domain and such that the PM domain lock cannot be acquired if the status is GPD_STATE_BUSY. Make threads attempting to acquire a PM domain's lock wait until the status changes to either GPD_STATE_ACTIVE or GPD_STATE_POWER_OFF. This change by itself doesn't fix the deadlock problem mentioned above, but the mechanism introduced by it will be used for for this purpose by a subsequent patch. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-11 16:39:29 -06:00
GPD_STATE_BUSY, /* Something is happening to the PM domain */
PM / Domains: Allow callbacks to execute all runtime PM helpers A deadlock may occur if one of the PM domains' .start_device() or .stop_device() callbacks or a device driver's .runtime_suspend() or .runtime_resume() callback executed by the core generic PM domain code uses a "wrong" runtime PM helper function. This happens, for example, if .runtime_resume() from one device's driver calls pm_runtime_resume() for another device in the same PM domain. A similar situation may take place if a device's parent is in the same PM domain, in which case the runtime PM framework may execute pm_genpd_runtime_resume() automatically for the parent (if it is suspended at the moment). This, of course, is undesirable, so the generic PM domains code should be modified to prevent it from happening. The runtime PM framework guarantees that pm_genpd_runtime_suspend() and pm_genpd_runtime_resume() won't be executed in parallel for the same device, so the generic PM domains code need not worry about those cases. Still, it needs to prevent the other possible race conditions between pm_genpd_runtime_suspend(), pm_genpd_runtime_resume(), pm_genpd_poweron() and pm_genpd_poweroff() from happening and it needs to avoid deadlocks at the same time. To this end, modify the generic PM domains code to relax synchronization rules so that: * pm_genpd_poweron() doesn't wait for the PM domain status to change from GPD_STATE_BUSY. If it finds that the status is not GPD_STATE_POWER_OFF, it returns without powering the domain on (it may modify the status depending on the circumstances). * pm_genpd_poweroff() returns as soon as it finds that the PM domain's status changed from GPD_STATE_BUSY after it's released the PM domain's lock. * pm_genpd_runtime_suspend() doesn't wait for the PM domain status to change from GPD_STATE_BUSY after executing the domain's .stop_device() callback and executes pm_genpd_poweroff() only if pm_genpd_runtime_resume() is not executed in parallel. * pm_genpd_runtime_resume() doesn't wait for the PM domain status to change from GPD_STATE_BUSY after executing pm_genpd_poweron() and sets the domain's status to GPD_STATE_BUSY and increments its counter of resuming devices (introduced by this change) immediately after acquiring the lock. The counter of resuming devices is then decremented after executing __pm_genpd_runtime_resume() for the device and the domain's status is reset to GPD_STATE_ACTIVE (unless there are more resuming devices in the domain, in which case the status remains GPD_STATE_BUSY). This way, for example, if a device driver's .runtime_resume() callback executes pm_runtime_resume() for another device in the same PM domain, pm_genpd_poweron() called by pm_genpd_runtime_resume() invoked by the runtime PM framework will not block and it will see that there's nothing to do for it. Next, the PM domain's lock will be acquired without waiting for its status to change from GPD_STATE_BUSY and the device driver's .runtime_resume() callback will be executed. In turn, if pm_runtime_suspend() is executed by one device driver's .runtime_resume() callback for another device in the same PM domain, pm_genpd_poweroff() executed by pm_genpd_runtime_suspend() invoked by the runtime PM framework as a result will notice that one of the devices in the domain is being resumed, so it will return immediately. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-11 16:39:36 -06:00
GPD_STATE_REPEAT, /* Power off in progress, to be repeated */
PM / Domains: Do not execute device callbacks under locks Currently, the .start_device() and .stop_device() callbacks from struct generic_pm_domain() as well as the device drivers' runtime PM callbacks used by the generic PM domains code are executed under the generic PM domain lock. This, unfortunately, is prone to deadlocks, for example if a device and its parent are boths members of the same PM domain. For this reason, it would be better if the PM domains code didn't execute device callbacks under the lock. Rework the locking in the generic PM domains code so that the lock is dropped for the execution of device callbacks. To this end, introduce PM domains states reflecting the current status of a PM domain and such that the PM domain lock cannot be acquired if the status is GPD_STATE_BUSY. Make threads attempting to acquire a PM domain's lock wait until the status changes to either GPD_STATE_ACTIVE or GPD_STATE_POWER_OFF. This change by itself doesn't fix the deadlock problem mentioned above, but the mechanism introduced by it will be used for for this purpose by a subsequent patch. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-11 16:39:29 -06:00
GPD_STATE_POWER_OFF, /* PM domain is off */
};
PM / Domains: System-wide transitions support for generic domains (v5) Make generic PM domains support system-wide power transitions (system suspend and hibernation). Add suspend, resume, freeze, thaw, poweroff and restore callbacks to be associated with struct generic_pm_domain objects and make pm_genpd_init() use them as appropriate. The new callbacks do nothing for devices belonging to power domains that were powered down at run time (before the transition). For the other devices the action carried out depends on the type of the transition. During system suspend the power domain .suspend() callback executes pm_generic_suspend() for the device, while the PM domain .suspend_noirq() callback runs pm_generic_suspend_noirq() for it, stops it and eventually removes power from the PM domain it belongs to (after all devices in the domain have been stopped and its subdomains have been powered off). During system resume the PM domain .resume_noirq() callback restores power to the PM domain (when executed for it first time), starts the device and executes pm_generic_resume_noirq() for it, while the .resume() callback executes pm_generic_resume() for the device. Finally, the .complete() callback executes pm_runtime_idle() for the device which should put it back into the suspended state if its runtime PM usage count is equal to zero at that time. The actions carried out during hibernation and resume from it are analogous to the ones described above. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:13:19 -06:00
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
struct dev_power_governor {
bool (*power_down_ok)(struct dev_pm_domain *domain);
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>
2011-11-30 16:02:05 -07:00
bool (*stop_ok)(struct device *dev);
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
};
PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-11-27 05:11:36 -07:00
struct gpd_dev_ops {
int (*start)(struct device *dev);
int (*stop)(struct device *dev);
PM / Domains: Introduce "save/restore state" device callbacks The current PM domains code uses device drivers' .runtime_suspend() and .runtime_resume() callbacks as the "save device state" and "restore device state" operations, which may not be appropriate in general, because it forces drivers to assume that they always will be used with generic PM domains. However, in theory, the same hardware may be used in devices that don't belong to any PM domain, in which case it would be necessary to add "fake" PM domains to satisfy the above assumption. It also may be located in a PM domain that's not handled with the help of the generic code. To allow device drivers that may be used along with the generic PM domains code of more flexibility, introduce new device callbacks, .save_state() and .restore_state(), that can be supplied by the drivers in addition to their "standard" runtime PM callbacks. This will allow the drivers to be designed to work with generic PM domains as well as without them. For backwards compatibility, introduce default .save_state() and .restore_state() callback routines for PM domains that will execute a device driver's .runtime_suspend() and .runtime_resume() callbacks, respectively, for the given device if the driver doesn't provide its own implementations of .save_state() and .restore_state(). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-27 05:11:44 -07:00
int (*save_state)(struct device *dev);
int (*restore_state)(struct device *dev);
PM / Domains: Rework system suspend callback routines (v2) The current generic PM domains code attempts to use the generic system suspend operations along with the domains' device stop/start routines, which requires device drivers to assume that their system suspend/resume (and hibernation/restore) callbacks will always be used with generic PM domains. However, in theory, the same hardware may be used in devices that don't belong to any PM domain, in which case it would be necessary to add "fake" PM domains to satisfy the above assumption. Also, the domain the hardware belongs to may not be handled with the help of the generic code. To allow device drivers that may be used along with the generic PM domains code of more flexibility, add new device callbacks, .suspend(), .suspend_late(), .resume_early(), .resume(), .freeze(), .freeze_late(), .thaw_early(), and .thaw(), that can be supplied by the drivers in addition to their "standard" system suspend and hibernation callbacks. These new callbacks, if defined, will be used by the generic PM domains code for the handling of system suspend and hibernation instead of the "standard" ones. This will allow drivers to be designed to work with generic PM domains as well as without them. For backwards compatibility, introduce default implementations of the new callbacks for PM domains that will execute pm_generic_suspend(), pm_generic_suspend_noirq(), pm_generic_resume_noirq(), pm_generic_resume(), pm_generic_freeze(), pm_generic_freeze_noirq(), pm_generic_thaw_noirq(), and pm_generic_thaw(), respectively, for the given device if its driver doesn't define those callbacks. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-27 05:11:51 -07:00
int (*suspend)(struct device *dev);
int (*suspend_late)(struct device *dev);
int (*resume_early)(struct device *dev);
int (*resume)(struct device *dev);
int (*freeze)(struct device *dev);
int (*freeze_late)(struct device *dev);
int (*thaw_early)(struct device *dev);
int (*thaw)(struct device *dev);
PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-11-27 05:11:36 -07:00
bool (*active_wakeup)(struct device *dev);
};
PM / Domains: Add preliminary support for cpuidle, v2 On some systems there are CPU cores located in the same power domains as I/O devices. Then, power can only be removed from the domain if all I/O devices in it are not in use and the CPU core is idle. Add preliminary support for that to the generic PM domains framework. First, the platform is expected to provide a cpuidle driver with one extra state designated for use with the generic PM domains code. This state should be initially disabled and its exit_latency value should be set to whatever time is needed to bring up the CPU core itself after restoring power to it, not including the domain's power on latency. Its .enter() callback should point to a procedure that will remove power from the domain containing the CPU core at the end of the CPU power transition. The remaining characteristics of the extra cpuidle state, referred to as the "domain" cpuidle state below, (e.g. power usage, target residency) should be populated in accordance with the properties of the hardware. Next, the platform should execute genpd_attach_cpuidle() on the PM domain containing the CPU core. That will cause the generic PM domains framework to treat that domain in a special way such that: * When all devices in the domain have been suspended and it is about to be turned off, the states of the devices will be saved, but power will not be removed from the domain. Instead, the "domain" cpuidle state will be enabled so that power can be removed from the domain when the CPU core is idle and the state has been chosen as the target by the cpuidle governor. * When the first I/O device in the domain is resumed and __pm_genpd_poweron(() is called for the first time after power has been removed from the domain, the "domain" cpuidle state will be disabled to avoid subsequent surprise power removals via cpuidle. The effective exit_latency value of the "domain" cpuidle state depends on the time needed to bring up the CPU core itself after restoring power to it as well as on the power on latency of the domain containing the CPU core. Thus the "domain" cpuidle state's exit_latency has to be recomputed every time the domain's power on latency is updated, which may happen every time power is restored to the domain, if the measured power on latency is greater than the latency stored in the corresponding generic_pm_domain structure. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-07-03 11:07:42 -06:00
struct gpd_cpu_data {
unsigned int saved_exit_latency;
struct cpuidle_state *idle_state;
};
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
struct generic_pm_domain {
struct dev_pm_domain domain; /* PM domain operations */
PM / Domains: Introduce function to power off all unused PM domains Add a new function pm_genpd_poweroff_unused() queuing up the execution of pm_genpd_poweroff() for every initialized generic PM domain. Calling it will cause every generic PM domain without devices in use to be powered off. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-07-13 04:31:52 -06:00
struct list_head gpd_list_node; /* Node in the global PM domains list */
PM / Domains: Allow generic PM domains to have multiple masters Currently, for a given generic PM domain there may be only one parent domain (i.e. a PM domain it depends on). However, there is at least one real-life case in which there should be two parents (masters) for one PM domain (the A3RV domain on SH7372 turns out to depend on the A4LC domain and it depends on the A4R domain and the same time). For this reason, allow a PM domain to have multiple parents (masters) by introducing objects representing links between PM domains. The (logical) links between PM domains represent relationships in which one domain is a master (i.e. it is depended on) and another domain is a slave (i.e. it depends on the master) with the rule that the slave cannot be powered on if the master is not powered on and the master cannot be powered off if the slave is not powered off. Each struct generic_pm_domain object representing a PM domain has two lists of links, a list of links in which it is a master and a list of links in which it is a slave. The first of these lists replaces the list of subdomains and the second one is used in place of the parent pointer. Each link is represented by struct gpd_link object containing pointers to the master and the slave and two struct list_head members allowing it to hook into two lists (the master's list of "master" links and the slave's list of "slave" links). This allows the code to get to the link from each side (either from the master or from the slave) and follow it in each direction. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-08 15:43:40 -06:00
struct list_head master_links; /* Links with PM domain as a master */
struct list_head slave_links; /* Links with PM domain as a slave */
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
struct list_head dev_list; /* List of devices */
struct mutex lock;
struct dev_power_governor *gov;
struct work_struct power_off_work;
PM / Domains: Make it possible to assign names to generic PM domains Add a name member pointer to struct generic_pm_domain and use it in diagnostic messages regarding the domain power-off and power-on latencies. Update the ARM shmobile SH7372 code to assign names to the PM domains used by it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-12-06 14:19:54 -07:00
char *name;
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
unsigned int in_progress; /* Number of devices being suspended now */
PM / Domains: Implement subdomain counters as atomic fields Currently, pm_genpd_poweron() and pm_genpd_poweroff() need to take the parent PM domain's lock in order to modify the parent's counter of active subdomains in a nonracy way. This causes the locking to be considerably complex and in fact is not necessary, because the subdomain counters may be implemented as atomic fields and they won't have to be modified under a lock. Replace the unsigned in sd_count field in struct generic_pm_domain by an atomic_t one and modify the code in drivers/base/power/domain.c to take this change into account. This patch doesn't change the locking yet, that is going to be done in a separate subsequent patch. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-08 15:43:04 -06:00
atomic_t sd_count; /* Number of subdomains with power "on" */
PM / Domains: Do not execute device callbacks under locks Currently, the .start_device() and .stop_device() callbacks from struct generic_pm_domain() as well as the device drivers' runtime PM callbacks used by the generic PM domains code are executed under the generic PM domain lock. This, unfortunately, is prone to deadlocks, for example if a device and its parent are boths members of the same PM domain. For this reason, it would be better if the PM domains code didn't execute device callbacks under the lock. Rework the locking in the generic PM domains code so that the lock is dropped for the execution of device callbacks. To this end, introduce PM domains states reflecting the current status of a PM domain and such that the PM domain lock cannot be acquired if the status is GPD_STATE_BUSY. Make threads attempting to acquire a PM domain's lock wait until the status changes to either GPD_STATE_ACTIVE or GPD_STATE_POWER_OFF. This change by itself doesn't fix the deadlock problem mentioned above, but the mechanism introduced by it will be used for for this purpose by a subsequent patch. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-11 16:39:29 -06:00
enum gpd_status status; /* Current state of the domain */
wait_queue_head_t status_wait_queue;
PM / Domains: Allow callbacks to execute all runtime PM helpers A deadlock may occur if one of the PM domains' .start_device() or .stop_device() callbacks or a device driver's .runtime_suspend() or .runtime_resume() callback executed by the core generic PM domain code uses a "wrong" runtime PM helper function. This happens, for example, if .runtime_resume() from one device's driver calls pm_runtime_resume() for another device in the same PM domain. A similar situation may take place if a device's parent is in the same PM domain, in which case the runtime PM framework may execute pm_genpd_runtime_resume() automatically for the parent (if it is suspended at the moment). This, of course, is undesirable, so the generic PM domains code should be modified to prevent it from happening. The runtime PM framework guarantees that pm_genpd_runtime_suspend() and pm_genpd_runtime_resume() won't be executed in parallel for the same device, so the generic PM domains code need not worry about those cases. Still, it needs to prevent the other possible race conditions between pm_genpd_runtime_suspend(), pm_genpd_runtime_resume(), pm_genpd_poweron() and pm_genpd_poweroff() from happening and it needs to avoid deadlocks at the same time. To this end, modify the generic PM domains code to relax synchronization rules so that: * pm_genpd_poweron() doesn't wait for the PM domain status to change from GPD_STATE_BUSY. If it finds that the status is not GPD_STATE_POWER_OFF, it returns without powering the domain on (it may modify the status depending on the circumstances). * pm_genpd_poweroff() returns as soon as it finds that the PM domain's status changed from GPD_STATE_BUSY after it's released the PM domain's lock. * pm_genpd_runtime_suspend() doesn't wait for the PM domain status to change from GPD_STATE_BUSY after executing the domain's .stop_device() callback and executes pm_genpd_poweroff() only if pm_genpd_runtime_resume() is not executed in parallel. * pm_genpd_runtime_resume() doesn't wait for the PM domain status to change from GPD_STATE_BUSY after executing pm_genpd_poweron() and sets the domain's status to GPD_STATE_BUSY and increments its counter of resuming devices (introduced by this change) immediately after acquiring the lock. The counter of resuming devices is then decremented after executing __pm_genpd_runtime_resume() for the device and the domain's status is reset to GPD_STATE_ACTIVE (unless there are more resuming devices in the domain, in which case the status remains GPD_STATE_BUSY). This way, for example, if a device driver's .runtime_resume() callback executes pm_runtime_resume() for another device in the same PM domain, pm_genpd_poweron() called by pm_genpd_runtime_resume() invoked by the runtime PM framework will not block and it will see that there's nothing to do for it. Next, the PM domain's lock will be acquired without waiting for its status to change from GPD_STATE_BUSY and the device driver's .runtime_resume() callback will be executed. In turn, if pm_runtime_suspend() is executed by one device driver's .runtime_resume() callback for another device in the same PM domain, pm_genpd_poweroff() executed by pm_genpd_runtime_suspend() invoked by the runtime PM framework as a result will notice that one of the devices in the domain is being resumed, so it will return immediately. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-11 16:39:36 -06:00
struct task_struct *poweroff_task; /* Powering off task */
unsigned int resume_count; /* Number of devices being resumed */
PM / Domains: System-wide transitions support for generic domains (v5) Make generic PM domains support system-wide power transitions (system suspend and hibernation). Add suspend, resume, freeze, thaw, poweroff and restore callbacks to be associated with struct generic_pm_domain objects and make pm_genpd_init() use them as appropriate. The new callbacks do nothing for devices belonging to power domains that were powered down at run time (before the transition). For the other devices the action carried out depends on the type of the transition. During system suspend the power domain .suspend() callback executes pm_generic_suspend() for the device, while the PM domain .suspend_noirq() callback runs pm_generic_suspend_noirq() for it, stops it and eventually removes power from the PM domain it belongs to (after all devices in the domain have been stopped and its subdomains have been powered off). During system resume the PM domain .resume_noirq() callback restores power to the PM domain (when executed for it first time), starts the device and executes pm_generic_resume_noirq() for it, while the .resume() callback executes pm_generic_resume() for the device. Finally, the .complete() callback executes pm_runtime_idle() for the device which should put it back into the suspended state if its runtime PM usage count is equal to zero at that time. The actions carried out during hibernation and resume from it are analogous to the ones described above. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:13:19 -06:00
unsigned int device_count; /* Number of devices */
unsigned int suspended_count; /* System suspend device counter */
unsigned int prepared_count; /* Suspend counter of prepared devices */
bool suspend_power_off; /* Power status before system suspend */
PM / Domains: Preliminary support for devices with power.irq_safe set The generic PM domains framework currently doesn't work with devices whose power.irq_safe flag is set, because runtime PM callbacks for such devices are run with interrupts disabled and the callbacks provided by the generic PM domains framework use domain mutexes and may sleep. However, such devices very well may belong to power domains on some systems, so the generic PM domains framework should take them into account. For this reason, modify the generic PM domains framework so that the domain .power_off() and .power_on() callbacks are never executed for a domain containing devices with power.irq_safe set, although the .stop_device() and .start_device() callbacks are still run for them. Additionally, introduce a flag allowing the creator of a struct generic_pm_domain object to indicate that its .stop_device() and .start_device() callbacks may be run in interrupt context (might_sleep_if() triggers if that flag is not set and one of those callbacks is run in interrupt context). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25 07:37:04 -06:00
bool dev_irq_safe; /* Device callbacks are IRQ-safe */
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
int (*power_off)(struct generic_pm_domain *domain);
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>
2011-11-30 16:02:10 -07:00
s64 power_off_latency_ns;
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
int (*power_on)(struct generic_pm_domain *domain);
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>
2011-11-30 16:02:10 -07:00
s64 power_on_latency_ns;
PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-11-27 05:11:36 -07:00
struct gpd_dev_ops dev_ops;
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>
2011-11-30 16:02:10 -07:00
s64 max_off_time_ns; /* Maximum allowed "suspended" time. */
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>
2012-05-01 13:34:07 -06:00
bool max_off_time_changed;
bool cached_power_down_ok;
PM / Domains: Add OF support A device node pointer is added to generic pm domain structure to associate the domain with a node in the device tree. The platform code parses the device tree to find available nodes representing the generic power domain, instantiates the available domains and initializes them by calling pm_genpd_init(). Nodes representing the devices include a phandle of the power domain to which it belongs. As these devices get instantiated, the driver code checkes for availability of a power domain phandle, converts the phandle to a device node and uses the new pm_genpd_of_add_device() api to associate the device with a power domain. pm_genpd_of_add_device() runs through its list of registered power domains and matches the OF node of the domain with the one specified as the parameter. If a match is found, the device is associated with the matched domain. Cc: Rob Herring <rob.herring@calxeda.com> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-01-26 23:22:07 -07:00
struct device_node *of_node; /* Node in device tree */
PM / Domains: Add preliminary support for cpuidle, v2 On some systems there are CPU cores located in the same power domains as I/O devices. Then, power can only be removed from the domain if all I/O devices in it are not in use and the CPU core is idle. Add preliminary support for that to the generic PM domains framework. First, the platform is expected to provide a cpuidle driver with one extra state designated for use with the generic PM domains code. This state should be initially disabled and its exit_latency value should be set to whatever time is needed to bring up the CPU core itself after restoring power to it, not including the domain's power on latency. Its .enter() callback should point to a procedure that will remove power from the domain containing the CPU core at the end of the CPU power transition. The remaining characteristics of the extra cpuidle state, referred to as the "domain" cpuidle state below, (e.g. power usage, target residency) should be populated in accordance with the properties of the hardware. Next, the platform should execute genpd_attach_cpuidle() on the PM domain containing the CPU core. That will cause the generic PM domains framework to treat that domain in a special way such that: * When all devices in the domain have been suspended and it is about to be turned off, the states of the devices will be saved, but power will not be removed from the domain. Instead, the "domain" cpuidle state will be enabled so that power can be removed from the domain when the CPU core is idle and the state has been chosen as the target by the cpuidle governor. * When the first I/O device in the domain is resumed and __pm_genpd_poweron(() is called for the first time after power has been removed from the domain, the "domain" cpuidle state will be disabled to avoid subsequent surprise power removals via cpuidle. The effective exit_latency value of the "domain" cpuidle state depends on the time needed to bring up the CPU core itself after restoring power to it as well as on the power on latency of the domain containing the CPU core. Thus the "domain" cpuidle state's exit_latency has to be recomputed every time the domain's power on latency is updated, which may happen every time power is restored to the domain, if the measured power on latency is greater than the latency stored in the corresponding generic_pm_domain structure. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-07-03 11:07:42 -06:00
struct gpd_cpu_data *cpu_data;
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
};
PM / Domains: System-wide transitions support for generic domains (v5) Make generic PM domains support system-wide power transitions (system suspend and hibernation). Add suspend, resume, freeze, thaw, poweroff and restore callbacks to be associated with struct generic_pm_domain objects and make pm_genpd_init() use them as appropriate. The new callbacks do nothing for devices belonging to power domains that were powered down at run time (before the transition). For the other devices the action carried out depends on the type of the transition. During system suspend the power domain .suspend() callback executes pm_generic_suspend() for the device, while the PM domain .suspend_noirq() callback runs pm_generic_suspend_noirq() for it, stops it and eventually removes power from the PM domain it belongs to (after all devices in the domain have been stopped and its subdomains have been powered off). During system resume the PM domain .resume_noirq() callback restores power to the PM domain (when executed for it first time), starts the device and executes pm_generic_resume_noirq() for it, while the .resume() callback executes pm_generic_resume() for the device. Finally, the .complete() callback executes pm_runtime_idle() for the device which should put it back into the suspended state if its runtime PM usage count is equal to zero at that time. The actions carried out during hibernation and resume from it are analogous to the ones described above. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:13:19 -06:00
static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)
{
return container_of(pd, struct generic_pm_domain, domain);
}
PM / Domains: Allow generic PM domains to have multiple masters Currently, for a given generic PM domain there may be only one parent domain (i.e. a PM domain it depends on). However, there is at least one real-life case in which there should be two parents (masters) for one PM domain (the A3RV domain on SH7372 turns out to depend on the A4LC domain and it depends on the A4R domain and the same time). For this reason, allow a PM domain to have multiple parents (masters) by introducing objects representing links between PM domains. The (logical) links between PM domains represent relationships in which one domain is a master (i.e. it is depended on) and another domain is a slave (i.e. it depends on the master) with the rule that the slave cannot be powered on if the master is not powered on and the master cannot be powered off if the slave is not powered off. Each struct generic_pm_domain object representing a PM domain has two lists of links, a list of links in which it is a master and a list of links in which it is a slave. The first of these lists replaces the list of subdomains and the second one is used in place of the parent pointer. Each link is represented by struct gpd_link object containing pointers to the master and the slave and two struct list_head members allowing it to hook into two lists (the master's list of "master" links and the slave's list of "slave" links). This allows the code to get to the link from each side (either from the master or from the slave) and follow it in each direction. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-08 15:43:40 -06:00
struct gpd_link {
struct generic_pm_domain *master;
struct list_head master_node;
struct generic_pm_domain *slave;
struct list_head slave_node;
};
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>
2011-11-30 16:02:05 -07:00
struct gpd_timing_data {
s64 stop_latency_ns;
s64 start_latency_ns;
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>
2011-11-30 16:02:10 -07:00
s64 save_state_latency_ns;
s64 restore_state_latency_ns;
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>
2012-04-29 14:54:17 -06:00
s64 effective_constraint_ns;
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>
2012-05-01 13:34:07 -06:00
bool constraint_changed;
bool cached_stop_ok;
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>
2011-11-30 16:02:05 -07:00
};
PM / Domains: Split device PM domain data into base and need_restore The struct pm_domain_data data type is defined in such a way that adding new fields specific to the generic PM domains code will require include/linux/pm.h to be modified. As a result, data types used only by the generic PM domains code will be defined in two headers, although they all should be defined in pm_domain.h and pm.h will need to include more headers, which won't be very nice. For this reason change the definition of struct pm_subsys_data so that its domain_data member is a pointer, which will allow struct pm_domain_data to be subclassed by various PM domains implementations. Remove the need_restore member from struct pm_domain_data and make the generic PM domains code subclass it by adding the need_restore member to the new data type. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-09-26 12:22:02 -06:00
struct generic_pm_domain_data {
struct pm_domain_data base;
PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-11-27 05:11:36 -07:00
struct gpd_dev_ops ops;
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>
2011-11-30 16:02:05 -07:00
struct gpd_timing_data td;
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>
2012-05-01 13:34:07 -06:00
struct notifier_block nb;
struct mutex lock;
PM / Domains: Add device domain data reference counter Add a mechanism for counting references to the struct generic_pm_domain_data object pointed to by dev->power.subsys_data->domain_data if the device in question belongs to a generic PM domain. This change is necessary for a subsequent patch making it possible to allocate that object from within pm_genpd_add_callbacks(), so that drivers can attach their PM domain device callbacks to devices before those devices are added to PM domains. This patch has been tested on the SH7372 Mackerel board. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-05 14:12:32 -06:00
unsigned int refcount;
PM / Domains: Split device PM domain data into base and need_restore The struct pm_domain_data data type is defined in such a way that adding new fields specific to the generic PM domains code will require include/linux/pm.h to be modified. As a result, data types used only by the generic PM domains code will be defined in two headers, although they all should be defined in pm_domain.h and pm.h will need to include more headers, which won't be very nice. For this reason change the definition of struct pm_subsys_data so that its domain_data member is a pointer, which will allow struct pm_domain_data to be subclassed by various PM domains implementations. Remove the need_restore member from struct pm_domain_data and make the generic PM domains code subclass it by adding the need_restore member to the new data type. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-09-26 12:22:02 -06:00
bool need_restore;
PM / Domains: Introduce "always on" device flag The TMU device on the Mackerel board belongs to the A4R power domain and loses power when the domain is turned off. Unfortunately, the TMU driver is not prepared to cope with such situations and crashes the system when that happens. To work around this problem introduce a new helper function, pm_genpd_dev_always_on(), allowing a device driver to mark its device as "always on" in case it belongs to a PM domain, which will make the generic PM domains core code avoid powering off the domain containing the device, both at run time and during system suspend. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Tested-by: Simon Horman <horms@verge.net.au> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: stable@vger.kernel.org
2012-03-13 15:39:48 -06:00
bool always_on;
PM / Domains: Split device PM domain data into base and need_restore The struct pm_domain_data data type is defined in such a way that adding new fields specific to the generic PM domains code will require include/linux/pm.h to be modified. As a result, data types used only by the generic PM domains code will be defined in two headers, although they all should be defined in pm_domain.h and pm.h will need to include more headers, which won't be very nice. For this reason change the definition of struct pm_subsys_data so that its domain_data member is a pointer, which will allow struct pm_domain_data to be subclassed by various PM domains implementations. Remove the need_restore member from struct pm_domain_data and make the generic PM domains code subclass it by adding the need_restore member to the new data type. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-09-26 12:22:02 -06:00
};
PM / Domains: Provide a dummy dev_gpd_data() when generic domains are not used dev_gpd_data() is a generic macro, also useful for drivers. Hence it should be available also when CONFIG_PM_GENERIC_DOMAINS is not selected. OTOH, to_gpd_data() is so far unused outside of the generic PM domain code and does not seem to be very useful without CONFIG_PM_GENERIC_DOMAINS. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-04 14:26:49 -07:00
#ifdef CONFIG_PM_GENERIC_DOMAINS
PM / Domains: Split device PM domain data into base and need_restore The struct pm_domain_data data type is defined in such a way that adding new fields specific to the generic PM domains code will require include/linux/pm.h to be modified. As a result, data types used only by the generic PM domains code will be defined in two headers, although they all should be defined in pm_domain.h and pm.h will need to include more headers, which won't be very nice. For this reason change the definition of struct pm_subsys_data so that its domain_data member is a pointer, which will allow struct pm_domain_data to be subclassed by various PM domains implementations. Remove the need_restore member from struct pm_domain_data and make the generic PM domains code subclass it by adding the need_restore member to the new data type. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-09-26 12:22:02 -06:00
static inline struct generic_pm_domain_data *to_gpd_data(struct pm_domain_data *pdd)
{
return container_of(pdd, struct generic_pm_domain_data, base);
}
PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-11-27 05:11:36 -07:00
static inline struct generic_pm_domain_data *dev_gpd_data(struct device *dev)
{
return to_gpd_data(dev->power.subsys_data->domain_data);
}
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>
2011-11-30 16:02:05 -07:00
extern struct dev_power_governor simple_qos_governor;
extern struct generic_pm_domain *dev_to_genpd(struct device *dev);
extern int __pm_genpd_add_device(struct generic_pm_domain *genpd,
struct device *dev,
struct gpd_timing_data *td);
PM / Domains: Add OF support A device node pointer is added to generic pm domain structure to associate the domain with a node in the device tree. The platform code parses the device tree to find available nodes representing the generic power domain, instantiates the available domains and initializes them by calling pm_genpd_init(). Nodes representing the devices include a phandle of the power domain to which it belongs. As these devices get instantiated, the driver code checkes for availability of a power domain phandle, converts the phandle to a device node and uses the new pm_genpd_of_add_device() api to associate the device with a power domain. pm_genpd_of_add_device() runs through its list of registered power domains and matches the OF node of the domain with the one specified as the parameter. If a match is found, the device is associated with the matched domain. Cc: Rob Herring <rob.herring@calxeda.com> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-01-26 23:22:07 -07:00
extern int __pm_genpd_of_add_device(struct device_node *genpd_node,
struct device *dev,
struct gpd_timing_data *td);
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>
2011-11-30 16:02:05 -07:00
static inline int pm_genpd_add_device(struct generic_pm_domain *genpd,
struct device *dev)
{
return __pm_genpd_add_device(genpd, dev, NULL);
}
PM / Domains: Add OF support A device node pointer is added to generic pm domain structure to associate the domain with a node in the device tree. The platform code parses the device tree to find available nodes representing the generic power domain, instantiates the available domains and initializes them by calling pm_genpd_init(). Nodes representing the devices include a phandle of the power domain to which it belongs. As these devices get instantiated, the driver code checkes for availability of a power domain phandle, converts the phandle to a device node and uses the new pm_genpd_of_add_device() api to associate the device with a power domain. pm_genpd_of_add_device() runs through its list of registered power domains and matches the OF node of the domain with the one specified as the parameter. If a match is found, the device is associated with the matched domain. Cc: Rob Herring <rob.herring@calxeda.com> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-01-26 23:22:07 -07:00
static inline int pm_genpd_of_add_device(struct device_node *genpd_node,
struct device *dev)
{
return __pm_genpd_of_add_device(genpd_node, dev, NULL);
}
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
extern int pm_genpd_remove_device(struct generic_pm_domain *genpd,
struct device *dev);
PM / Domains: Introduce "always on" device flag The TMU device on the Mackerel board belongs to the A4R power domain and loses power when the domain is turned off. Unfortunately, the TMU driver is not prepared to cope with such situations and crashes the system when that happens. To work around this problem introduce a new helper function, pm_genpd_dev_always_on(), allowing a device driver to mark its device as "always on" in case it belongs to a PM domain, which will make the generic PM domains core code avoid powering off the domain containing the device, both at run time and during system suspend. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Tested-by: Simon Horman <horms@verge.net.au> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: stable@vger.kernel.org
2012-03-13 15:39:48 -06:00
extern void pm_genpd_dev_always_on(struct device *dev, bool val);
PM / Domains: Make it possible to add devices to inactive domains The generic PM domains core code currently requires domains to be in the "power on" state for adding devices to them, but this limitation turns out to be inconvenient in some situations, so remove it. For this purpose, make __pm_genpd_add_device() set the device's need_restore flag if the domain is in the "power off" state, so that the device's "restore state" (usually .runtime_resume()) callback is executed when it is resumed after the domain has been turned on. If the domain is in the "power on" state, the device's need_restore flag will be cleared by __pm_genpd_add_device(), so that its "save state" (usually .runtime_suspend()) callback is executed when the domain is about to be turned off. However, since that default behavior need not be always desirable, add a helper function pm_genpd_dev_need_restore() allowing a device's need_restore flag to be set/unset at any time. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-14 13:45:52 -06:00
extern void pm_genpd_dev_need_restore(struct device *dev, bool val);
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
extern int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *new_subdomain);
extern int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *target);
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>
2011-11-30 16:02:05 -07:00
extern int pm_genpd_add_callbacks(struct device *dev,
struct gpd_dev_ops *ops,
struct gpd_timing_data *td);
extern int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td);
PM / Domains: Add preliminary support for cpuidle, v2 On some systems there are CPU cores located in the same power domains as I/O devices. Then, power can only be removed from the domain if all I/O devices in it are not in use and the CPU core is idle. Add preliminary support for that to the generic PM domains framework. First, the platform is expected to provide a cpuidle driver with one extra state designated for use with the generic PM domains code. This state should be initially disabled and its exit_latency value should be set to whatever time is needed to bring up the CPU core itself after restoring power to it, not including the domain's power on latency. Its .enter() callback should point to a procedure that will remove power from the domain containing the CPU core at the end of the CPU power transition. The remaining characteristics of the extra cpuidle state, referred to as the "domain" cpuidle state below, (e.g. power usage, target residency) should be populated in accordance with the properties of the hardware. Next, the platform should execute genpd_attach_cpuidle() on the PM domain containing the CPU core. That will cause the generic PM domains framework to treat that domain in a special way such that: * When all devices in the domain have been suspended and it is about to be turned off, the states of the devices will be saved, but power will not be removed from the domain. Instead, the "domain" cpuidle state will be enabled so that power can be removed from the domain when the CPU core is idle and the state has been chosen as the target by the cpuidle governor. * When the first I/O device in the domain is resumed and __pm_genpd_poweron(() is called for the first time after power has been removed from the domain, the "domain" cpuidle state will be disabled to avoid subsequent surprise power removals via cpuidle. The effective exit_latency value of the "domain" cpuidle state depends on the time needed to bring up the CPU core itself after restoring power to it as well as on the power on latency of the domain containing the CPU core. Thus the "domain" cpuidle state's exit_latency has to be recomputed every time the domain's power on latency is updated, which may happen every time power is restored to the domain, if the measured power on latency is greater than the latency stored in the corresponding generic_pm_domain structure. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-07-03 11:07:42 -06:00
extern int genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state);
extern int genpd_detach_cpuidle(struct generic_pm_domain *genpd);
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
extern void pm_genpd_init(struct generic_pm_domain *genpd,
struct dev_power_governor *gov, bool is_off);
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>
2011-11-30 16:02:05 -07:00
PM / Domains: Export pm_genpd_poweron() in header Allow SoC-specific code to call pm_genpd_poweron(). Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-10 02:39:14 -06:00
extern int pm_genpd_poweron(struct generic_pm_domain *genpd);
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>
2011-11-30 16:02:05 -07:00
extern bool default_stop_ok(struct device *dev);
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>
2011-12-08 15:27:28 -07:00
extern struct dev_power_governor pm_domain_always_on_gov;
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
#else
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>
2011-11-30 16:02:05 -07:00
PM / Domains: Fix include for PM_GENERIC_DOMAINS=n case Fix pm_genpd_init() arguments and make sure dev_gpd_data() and simple_qos_governor exist regardless of CONFIG_PM_GENERIC_DOMAINS setting. Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-25 14:14:18 -07:00
static inline struct generic_pm_domain_data *dev_gpd_data(struct device *dev)
{
return ERR_PTR(-ENOSYS);
}
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>
2011-11-30 16:02:05 -07:00
static inline struct generic_pm_domain *dev_to_genpd(struct device *dev)
{
return ERR_PTR(-ENOSYS);
}
static inline int __pm_genpd_add_device(struct generic_pm_domain *genpd,
struct device *dev,
struct gpd_timing_data *td)
{
return -ENOSYS;
}
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
static inline int pm_genpd_add_device(struct generic_pm_domain *genpd,
struct device *dev)
{
return -ENOSYS;
}
static inline int pm_genpd_remove_device(struct generic_pm_domain *genpd,
struct device *dev)
{
return -ENOSYS;
}
PM / Domains: Introduce "always on" device flag The TMU device on the Mackerel board belongs to the A4R power domain and loses power when the domain is turned off. Unfortunately, the TMU driver is not prepared to cope with such situations and crashes the system when that happens. To work around this problem introduce a new helper function, pm_genpd_dev_always_on(), allowing a device driver to mark its device as "always on" in case it belongs to a PM domain, which will make the generic PM domains core code avoid powering off the domain containing the device, both at run time and during system suspend. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Tested-by: Simon Horman <horms@verge.net.au> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: stable@vger.kernel.org
2012-03-13 15:39:48 -06:00
static inline void pm_genpd_dev_always_on(struct device *dev, bool val) {}
PM / Domains: Make it possible to add devices to inactive domains The generic PM domains core code currently requires domains to be in the "power on" state for adding devices to them, but this limitation turns out to be inconvenient in some situations, so remove it. For this purpose, make __pm_genpd_add_device() set the device's need_restore flag if the domain is in the "power off" state, so that the device's "restore state" (usually .runtime_resume()) callback is executed when it is resumed after the domain has been turned on. If the domain is in the "power on" state, the device's need_restore flag will be cleared by __pm_genpd_add_device(), so that its "save state" (usually .runtime_suspend()) callback is executed when the domain is about to be turned off. However, since that default behavior need not be always desirable, add a helper function pm_genpd_dev_need_restore() allowing a device's need_restore flag to be set/unset at any time. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-14 13:45:52 -06:00
static inline void pm_genpd_dev_need_restore(struct device *dev, bool val) {}
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
static inline int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *new_sd)
{
return -ENOSYS;
}
static inline int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *target)
{
return -ENOSYS;
}
PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-11-27 05:11:36 -07:00
static inline int pm_genpd_add_callbacks(struct device *dev,
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>
2011-11-30 16:02:05 -07:00
struct gpd_dev_ops *ops,
struct gpd_timing_data *td)
PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-11-27 05:11:36 -07:00
{
return -ENOSYS;
}
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>
2011-11-30 16:02:05 -07:00
static inline int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td)
PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-11-27 05:11:36 -07:00
{
return -ENOSYS;
}
PM / Domains: Add preliminary support for cpuidle, v2 On some systems there are CPU cores located in the same power domains as I/O devices. Then, power can only be removed from the domain if all I/O devices in it are not in use and the CPU core is idle. Add preliminary support for that to the generic PM domains framework. First, the platform is expected to provide a cpuidle driver with one extra state designated for use with the generic PM domains code. This state should be initially disabled and its exit_latency value should be set to whatever time is needed to bring up the CPU core itself after restoring power to it, not including the domain's power on latency. Its .enter() callback should point to a procedure that will remove power from the domain containing the CPU core at the end of the CPU power transition. The remaining characteristics of the extra cpuidle state, referred to as the "domain" cpuidle state below, (e.g. power usage, target residency) should be populated in accordance with the properties of the hardware. Next, the platform should execute genpd_attach_cpuidle() on the PM domain containing the CPU core. That will cause the generic PM domains framework to treat that domain in a special way such that: * When all devices in the domain have been suspended and it is about to be turned off, the states of the devices will be saved, but power will not be removed from the domain. Instead, the "domain" cpuidle state will be enabled so that power can be removed from the domain when the CPU core is idle and the state has been chosen as the target by the cpuidle governor. * When the first I/O device in the domain is resumed and __pm_genpd_poweron(() is called for the first time after power has been removed from the domain, the "domain" cpuidle state will be disabled to avoid subsequent surprise power removals via cpuidle. The effective exit_latency value of the "domain" cpuidle state depends on the time needed to bring up the CPU core itself after restoring power to it as well as on the power on latency of the domain containing the CPU core. Thus the "domain" cpuidle state's exit_latency has to be recomputed every time the domain's power on latency is updated, which may happen every time power is restored to the domain, if the measured power on latency is greater than the latency stored in the corresponding generic_pm_domain structure. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-07-03 11:07:42 -06:00
static inline int genpd_attach_cpuidle(struct generic_pm_domain *genpd, int st)
{
return -ENOSYS;
}
static inline int genpd_detach_cpuidle(struct generic_pm_domain *genpd)
{
return -ENOSYS;
}
PM / Domains: Fix include for PM_GENERIC_DOMAINS=n case Fix pm_genpd_init() arguments and make sure dev_gpd_data() and simple_qos_governor exist regardless of CONFIG_PM_GENERIC_DOMAINS setting. Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-25 14:14:18 -07:00
static inline void pm_genpd_init(struct generic_pm_domain *genpd,
struct dev_power_governor *gov, bool is_off)
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>
2011-11-30 16:02:05 -07:00
{
}
PM / Domains: Export pm_genpd_poweron() in header Allow SoC-specific code to call pm_genpd_poweron(). Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-07-10 02:39:14 -06:00
static inline int pm_genpd_poweron(struct generic_pm_domain *genpd)
{
return -ENOSYS;
}
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>
2011-11-30 16:02:05 -07:00
static inline bool default_stop_ok(struct device *dev)
{
return false;
}
PM / Domains: Fix include for PM_GENERIC_DOMAINS=n case Fix pm_genpd_init() arguments and make sure dev_gpd_data() and simple_qos_governor exist regardless of CONFIG_PM_GENERIC_DOMAINS setting. Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-25 14:14:18 -07:00
#define simple_qos_governor NULL
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>
2011-12-08 15:27:28 -07:00
#define pm_domain_always_on_gov NULL
PM / Domains: Fix build for CONFIG_PM_RUNTIME unset Function genpd_queue_power_off_work() is not defined for CONFIG_PM_RUNTIME, so pm_genpd_poweroff_unused() causes a build error to happen in that case. Fix the problem by making pm_genpd_poweroff_unused() depend on CONFIG_PM_RUNTIME too. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-14 05:34:31 -06:00
#endif
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>
2011-11-30 16:02:05 -07:00
static inline int pm_genpd_remove_callbacks(struct device *dev)
{
return __pm_genpd_remove_callbacks(dev, true);
}
PM / Domains: Fix build for CONFIG_PM_RUNTIME unset Function genpd_queue_power_off_work() is not defined for CONFIG_PM_RUNTIME, so pm_genpd_poweroff_unused() causes a build error to happen in that case. Fix the problem by making pm_genpd_poweroff_unused() depend on CONFIG_PM_RUNTIME too. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-14 05:34:31 -06:00
#ifdef CONFIG_PM_GENERIC_DOMAINS_RUNTIME
extern void genpd_queue_power_off_work(struct generic_pm_domain *genpd);
extern void pm_genpd_poweroff_unused(void);
#else
ARM / shmobile: Use genpd_queue_power_off_work() Make pd_power_down_a3rv() use genpd_queue_power_off_work() to queue up the powering off of the A4LC domain to avoid queuing it up when it is pending. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2011-07-14 12:59:07 -06:00
static inline void genpd_queue_power_off_work(struct generic_pm_domain *gpd) {}
PM / Domains: Fix build for CONFIG_PM_RUNTIME unset Function genpd_queue_power_off_work() is not defined for CONFIG_PM_RUNTIME, so pm_genpd_poweroff_unused() causes a build error to happen in that case. Fix the problem by making pm_genpd_poweroff_unused() depend on CONFIG_PM_RUNTIME too. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-14 05:34:31 -06:00
static inline void pm_genpd_poweroff_unused(void) {}
PM / Domains: Support for generic I/O PM domains (v8) Introduce common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_pm_domain to be used for representing power domains that each contain a number of devices and may be parent domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_off() is supposed to remove power from the entire power domain and ->power_on() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Introduce configuration option CONFIG_PM_GENERIC_DOMAINS to be selected by the platforms that want to use the new code. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-01 14:12:45 -06:00
#endif
#endif /* _LINUX_PM_DOMAIN_H */
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