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path: root/include/linux/pm_domain.h
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2015-08-29PM / Domains: Remove unusable governor dummiesGeert Uytterhoeven
The governor dummies for the !CONFIG_PM_GENERIC_DOMAINS case are unusable, as a governors is always referred to by taking its address, which you can't do with a literal NULL pointer. I.e. pm_genpd_init(genpd, &simple_qos_governor, false); fails to compile with: error: lvalue required as unary '&' operand Hence just remove the governor dummies. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-31PM / Domains: Remove intermediate states from the power off sequenceUlf Hansson
Genpd's ->runtime_suspend() (assigned to pm_genpd_runtime_suspend()) doesn't immediately walk the hierarchy of ->runtime_suspend() callbacks. Instead, pm_genpd_runtime_suspend() calls pm_genpd_poweroff() which postpones that until *all* the devices in the genpd are runtime suspended. When pm_genpd_poweroff() discovers that the last device in the genpd is about to be runtime suspended, it calls __pm_genpd_save_device() for *all* the devices in the genpd sequentially. Furthermore, __pm_genpd_save_device() invokes the ->start() callback, walks the hierarchy of the ->runtime_suspend() callbacks and invokes the ->stop() callback. This causes a "thundering herd" problem. Let's address this issue by having pm_genpd_runtime_suspend() immediately walk the hierarchy of the ->runtime_suspend() callbacks, instead of postponing that to the power off sequence via pm_genpd_poweroff(). If the selected ->runtime_suspend() callback doesn't return an error code, call pm_genpd_poweroff() to see if it's feasible to also power off the PM domain. Adopting this change enables us to simplify parts of the code in genpd, for example the locking mechanism. Additionally, it gives some positive side effects, as described below. i) One device's ->runtime_resume() latency is no longer affected by other devices' latencies in a genpd. The complexity genpd has to support the option to abort the power off sequence suffers from latency issues. More precisely, a device that is requested to be runtime resumed, may end up waiting for __pm_genpd_save_device() to complete its operations for *another* device. That's because pm_genpd_poweroff() can't confirm an abort request while it waits for __pm_genpd_save_device() to return. As this patch removes the intermediate states in pm_genpd_poweroff() while powering off the PM domain, we no longer need the ability to abort that sequence. ii) Make pm_runtime[_status]_suspended() reliable when used with genpd. Until the last device in a genpd becomes idle, pm_genpd_runtime_suspend() will return 0 without actually walking the hierarchy of the ->runtime_suspend() callbacks. However, by returning 0 the runtime PM core considers the device as runtime_suspended, so pm_runtime[_status]_suspended() will return true, even though the device isn't (yet) runtime suspended. After this patch, since pm_genpd_runtime_suspend() immediately walks the hierarchy of the ->runtime_suspend() callbacks, pm_runtime[_status]_suspended() will accurately reflect the status of the device. iii) Enable fine-grained PM through runtime PM callbacks in drivers/subsystems. There are currently cases were drivers/subsystems implements runtime PM callbacks to deploy fine-grained PM (e.g. gate clocks, move pinctrl to power-save state, etc.). While using the genpd, pm_genpd_runtime_suspend() postpones invoking these callbacks until *all* the devices in the genpd are runtime suspended. In essence, one runtime resumed device prevents fine-grained PM for other devices within the same genpd. After this patch, since pm_genpd_runtime_suspend() immediately walks the hierarchy of the ->runtime_suspend() callbacks, fine-grained PM is enabled throughout all the levels of runtime PM callbacks. iiii) Enable fine-grained PM for IRQ safe devices Per the definition for an IRQ safe device, its runtime PM callbacks must be able to execute in atomic context. In the path while genpd walks the hierarchy of the ->runtime_suspend() callbacks for the device, it uses a mutex. Therefore, genpd prevents that path to be executed for IRQ safe devices. As this patch changes pm_genpd_runtime_suspend() to immediately walk the hierarchy of the ->runtime_suspend() callbacks and without needing to use a mutex, fine-grained PM is enabled throughout all the levels of runtime PM callbacks for IRQ safe devices. Unfortunately this patch also comes with a drawback, as described in the summary below. Driver's/subsystem's runtime PM callbacks may be invoked even when the genpd hasn't actually powered off the PM domain, potentially introducing unnecessary latency. However, in most cases, saving/restoring register contexts for devices are typically fast operations or can be optimized in device specific ways (e.g. shadow copies of register contents in memory, device-specific checks to see if context has been lost before restoring context, etc.). Still, in some cases the driver/subsystem may suffer from latency if runtime PM is used in a very fine-grained manner (e.g. for each IO request or xfer). To prevent that extra overhead, the driver/subsystem may deploy the runtime PM autosuspend feature. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-22PM / domains: factor out code to get the generic PM domain from a struct deviceRussell King
The PM domain code contains two methods to get the generic PM domain for a struct device. One is dev_to_genpd() which is only safe when we know for certain that the device has a generic PM domain attached. The other is coded into genpd_dev_pm_detach() which ensures that the PM domain in the struct device is a generic PM domain (and so is safer). This commit factors out the safer version, documents it, and hides the unsafe dev_to_genpd(). Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03PM / Domains: Eliminate the mutex for the generic_pm_domain_dataUlf Hansson
While adding devices to their PM domains, dev_pm_qos_add_notifier() was invoked while allocating the generic_pm_domain_data for the device. Since the generic_pm_domain_data's device pointer will be assigned after allocation, the ->genpd_dev_pm_qos_notifier() callback could be called prior having a valid pointer to the device. Similar scenario existed while removing a device from a genpd. To cope with these scenarios a mutex was used to protect the pointer to the device. By re-order the sequence for when dev_pm_qos_add|remove_notifier() are invoked, we make sure the ->genpd_dev_pm_qos_notifier() callback are always called with a valid device pointer available. In this way, we eliminate the need for protecting the pointer and thus we can remove the mutex from the struct generic_pm_domain_data. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03PM / Domains: Remove reference counting for the generic_pm_domain_dataUlf Hansson
The reference counting was needed when genpd supported PM domain device callbacks. Since this option has been removed, let's also remove the reference counting of the struct generic_pm_domain_data. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-23PM / Domains: Remove pm_genpd_dev_need_restore() APIUlf Hansson
There are currently no users of this API, let's remove it. Additionally, if such feature would be needed future wise, a better option is likely use pm_runtime_set_active|suspended() in some form. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-29Merge branches 'pm-domains', 'powercap' and 'pm-tools'Rafael J. Wysocki
* pm-domains: PM / Domains: Export of_genpd_get_from_provider function * powercap: powercap / RAPL: add IDs for future Xeon CPUs * pm-tools: tools / cpupower: Fix no idle state information return value tools / cpupower: Correctly detect if running as root
2014-12-17PM / Domains: Export of_genpd_get_from_provider functionAmit Daniel Kachhap
This function looks up a PM domain form the provider. This will be useful to add parent/child domain relationship from the SoC specific code. The caller of the function must make sure that PM domain provider is already registered. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-08Merge branch 'pm-runtime'Rafael J. Wysocki
* pm-runtime: (25 commits) i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c dmaengine / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM e1000e / igb / PM: Eliminate CONFIG_PM_RUNTIME MMC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM MFD / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM misc / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM media / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM input / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM iio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM hsi / OMAP / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM i2c-hid / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM drm / exynos / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM gpio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM hwrandom / exynos / PM: Use CONFIG_PM in #ifdef block / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM USB / PM: Drop CONFIG_PM_RUNTIME from the USB core PM: Merge the SET*_RUNTIME_PM_OPS() macros PM / Kconfig: Do not select PM directly from Kconfig files PCI / PM: Drop CONFIG_PM_RUNTIME from the PCI core ...
2014-12-04PM: Drop CONFIG_PM_RUNTIME from the driver coreRafael J. Wysocki
After commit b2b49ccbdd54 (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so quite a few depend on CONFIG_PM or even may be dropped entirely in some cases. Replace CONFIG_PM_RUNTIME with CONFIG_PM in the PM core code. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-04PM / Domains: Initial PM clock support for genpdUlf Hansson
It's quite common for PM domains to use PM clocks. Typically from SOC specific code, the per device PM clock list is created and pm_clk_suspend|resume() are invoked to handle clock gating/ungating. A step towards consolidation is to integrate PM clock support into genpd, which is what this patch does. In this initial step, the calls to the pm_clk_suspend|resume() are handled within genpd, but the per device PM clock list still needs to be created from SOC specific code. It seems reasonable to have gendp to handle that as well, but that left to future patches to address. It's not every users of genpd that are keen on using PM clocks, thus we need to provide this a configuration option for genpd. Therefore let's add flag field in the genpd struct to keep this information and define a new GENDP_FLAG_PM_CLK bit for it. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-18Merge back 'pm-domains' material for 3.19-rc1.Rafael J. Wysocki
2014-11-18PM / Domains: Move struct pm_domain_data to pm_domain.hUlf Hansson
The definition of the struct pm_domain_data better belongs in the header for the PM domains, let's move it there. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-11PM / Domains: Fix initial default state of the need_restore flagUlf Hansson
The initial state of the device's need_restore flag should'nt depend on the current state of the PM domain. For example it should be perfectly valid to attach an inactive device to a powered PM domain. The pm_genpd_dev_need_restore() API allow us to update the need_restore flag to somewhat cope with such scenarios. Typically that should have been done from drivers/buses ->probe() since it's those that put the requirements on the value of the need_restore flag. Until recently, the Exynos SOCs were the only user of the pm_genpd_dev_need_restore() API, though invoking it from a centralized location while adding devices to their PM domains. Due to that Exynos now have swithed to the generic OF-based PM domain look-up, it's no longer possible to invoke the API from a centralized location. The reason is because devices are now added to their PM domains during the probe sequence. Commit "ARM: exynos: Move to generic PM domain DT bindings" did the switch for Exynos to the generic OF-based PM domain look-up, but it also removed the call to pm_genpd_dev_need_restore(). This caused a regression for some of the Exynos drivers. To handle things more properly in the generic PM domain, let's change the default initial value of the need_restore flag to reflect that the state is unknown. As soon as some of the runtime PM callbacks gets invoked, update the initial value accordingly. Moreover, since the generic PM domain is verifying that all devices are both runtime PM enabled and suspended, using pm_runtime_suspended() while pm_genpd_poweroff() is invoked from the scheduled work, we can be sure of that the PM domain won't be powering off while having active devices. Do note that, the generic PM domain can still only know about active devices which has been activated through invoking its runtime PM resume callback. In other words, buses/drivers using pm_runtime_set_active() during ->probe() will still suffer from a race condition, potentially probing a device without having its PM domain being powered. That issue will have to be solved using a different approach. This a log from the boot regression for Exynos5, which is being fixed in this patch. ------------[ cut here ]------------ WARNING: CPU: 0 PID: 308 at ../drivers/clk/clk.c:851 clk_disable+0x24/0x30() Modules linked in: CPU: 0 PID: 308 Comm: kworker/0:1 Not tainted 3.18.0-rc3-00569-gbd9449f-dirty #10 Workqueue: pm pm_runtime_work [<c0013c64>] (unwind_backtrace) from [<c0010dec>] (show_stack+0x10/0x14) [<c0010dec>] (show_stack) from [<c03ee4cc>] (dump_stack+0x70/0xbc) [<c03ee4cc>] (dump_stack) from [<c0020d34>] (warn_slowpath_common+0x64/0x88) [<c0020d34>] (warn_slowpath_common) from [<c0020d74>] (warn_slowpath_null+0x1c/0x24) [<c0020d74>] (warn_slowpath_null) from [<c03107b0>] (clk_disable+0x24/0x30) [<c03107b0>] (clk_disable) from [<c02cc834>] (gsc_runtime_suspend+0x128/0x160) [<c02cc834>] (gsc_runtime_suspend) from [<c0249024>] (pm_generic_runtime_suspend+0x2c/0x38) [<c0249024>] (pm_generic_runtime_suspend) from [<c024f44c>] (pm_genpd_default_save_state+0x2c/0x8c) [<c024f44c>] (pm_genpd_default_save_state) from [<c024ff2c>] (pm_genpd_poweroff+0x224/0x3ec) [<c024ff2c>] (pm_genpd_poweroff) from [<c02501b4>] (pm_genpd_runtime_suspend+0x9c/0xcc) [<c02501b4>] (pm_genpd_runtime_suspend) from [<c024a4f8>] (__rpm_callback+0x2c/0x60) [<c024a4f8>] (__rpm_callback) from [<c024a54c>] (rpm_callback+0x20/0x74) [<c024a54c>] (rpm_callback) from [<c024a930>] (rpm_suspend+0xd4/0x43c) [<c024a930>] (rpm_suspend) from [<c024bbcc>] (pm_runtime_work+0x80/0x90) [<c024bbcc>] (pm_runtime_work) from [<c0032a9c>] (process_one_work+0x12c/0x314) [<c0032a9c>] (process_one_work) from [<c0032cf4>] (worker_thread+0x3c/0x4b0) [<c0032cf4>] (worker_thread) from [<c003747c>] (kthread+0xcc/0xe8) [<c003747c>] (kthread) from [<c000e738>] (ret_from_fork+0x14/0x3c) ---[ end trace 40cd58bcd6988f12 ]--- Fixes: a4a8c2c4962bb655 (ARM: exynos: Move to generic PM domain DT bindings) Reported-and-tested0by: Sylwester Nawrocki <s.nawrocki@samsung.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-08PM / Domains: Change prototype for the attach and detach callbacksUlf Hansson
Convert the prototypes to return an int in order to support error handling in these callbacks. Also, as suggested by Dmitry Torokhov, pass the domain pointer for use inside the callbacks, and so that they match the existing power_on/power_off callbacks which currently take the domain pointer. Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> [ khilman: added domain as parameter to callbacks, as suggested by Dmitry ] Signed-off-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-03PM / Domains: Rename cpu_data to cpuidle_dataUlf Hansson
The "cpu_data" are defined for some archs and thus conflicting with the "cpu_data" member in the struct gpd_cpu_data. This causes a compiler error for those archs. Let's fix it by rename the member to cpuidle_data. In this context it also seems appropriate to rename the struct to gpd_cpuidle_data to better reflect its use. Fixes: f48c767ce895 (PM / Domains: Move dev_pm_domain_attach|detach() to pm_domain.h) Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-30PM / Domains: Move dev_pm_domain_attach|detach() to pm_domain.hUlf Hansson
The commit 46420dd73b80 (PM / Domains: Add APIs to attach/detach a PM domain for a device) started using errno values in pm.h header file. It also failed to include the header for these, thus it caused compiler errors. Instead of including the errno header to pm.h, let's move the functions to pm_domain.h, since it's a better match. Fixes: 46420dd73b80 (PM / Domains: Add APIs to attach/detach a PM domain for a device) Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-25PM / Domains: Remove legacy API for adding devices through DTUlf Hansson
There are no active clients of the legacy API and we now also have a better way to handle genpd DT support. So let's remove the legacy API. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-25PM / Domains: Add genpd attach/detach callbacksGeert Uytterhoeven
While a PM domain can enable PM runtime management of its devices' module clocks by setting genpd->dev_ops.stop = pm_clk_suspend; genpd->dev_ops.start = pm_clk_resume; this also requires registering the clocks with the pm_clk subsystem. In the legacy case, this is handled by the platform code, after attaching the device to its PM domain. When the devices are instantiated from DT, devices are attached to their PM domains by generic code, leaving no method for the platform-specific PM domain code to register their clocks. Add two callbacks, allowing a PM domain to perform platform-specific tasks when a device is attached to or detached from a PM domain. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-22PM / Domains: Add generic OF-based PM domain look-upTomasz Figa
This patch introduces generic code to perform PM domain look-up using device tree and automatically bind devices to their PM domains. Generic device tree bindings are introduced to specify PM domains of devices in their device tree nodes. Backwards compatibility with legacy Samsung-specific PM domain bindings is provided, but for now the new code is not compiled when CONFIG_ARCH_EXYNOS is selected to avoid collision with legacy code. This will change as soon as the Exynos PM domain code gets converted to use the generic framework in further patch. This patch was originally submitted by Tomasz Figa when he was employed by Samsung. Link: http://marc.info/?l=linux-pm&m=139955349702152&w=2 Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Rob Herring <robh@kernel.org> Tested-by: Philipp Zabel <p.zabel@pengutronix.de> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09PM / domains: Keep declaration of dev_power_governors togetherUlf Hansson
This is a pure code cleanup in the header file for the PM domain. No functional change. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09PM / domains: Remove default_stop_ok() APIUlf Hansson
There are currently no need to export default_stop_ok() as an API, instead let's keep it local to the PM domain governor. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09PM / domains: Remove genpd_queue_power_off_work() APIUlf Hansson
There are no active users of this API. Let's remove it and if future needs shows up we could consider to have a get/put API instead. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09PM / domains: Remove pm_genpd_syscore_switch() APIUlf Hansson
The pm_genpd_syscore_poweroff() API and pm_genpd_syscore_poweron() API makes the pm_genpd_syscore_switch() API redundant. Moreover, since there are no active users, let's just remove it. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09PM / domains: Remove dev_irq_safe from genpd configUlf Hansson
The genpd dev_irq_safe configuration somewhat overlaps with the runtime PM pm_runtime_irq_safe() option. Also, currently genpd don't have a good way to deal with these device. So, until we figured out if and how to support this in genpd, let's remove the option to configure it. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09PM / domains: Remove system PM callbacks from gpd_dev_opsUlf Hansson
There no users of these callbacks, let's simplify the generic power domain by removing them. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09PM / domains: Ignore callbacks for subsys generic_pm_domain_dataUlf Hansson
In a step of simplifying the generic power domain let's move away from using these callbacks. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-09PM / domains: Remove the pm_genpd_add|remove_callbacks APIsUlf Hansson
There are no users of these APIs. To simplify the generic power domain let's remove them. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-03PM / domains: Make generic_pm_domain.name constGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-09-04PM / Domains: Operations related to cpuidle using domain namesRafael J. Wysocki
Make it possible to use domain names in operations connecting cpuidle to and disconnecting it from a PM domain. This is useful on platforms where PM domain objects are organized in such a way that the names of the domains are easier to use than the addresses of those objects. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-04PM / Domains: Document cpuidle-related functions and change their namesRafael J. Wysocki
The names of the cpuidle-related functions in drivers/base/power/domain.c are inconsistent with the names of the other exported functions in that file (the "pm_" prefix is missing from them) and they are missing kerneldoc comments. Fix that by adding the missing "pm_" prefix to the names of those functions and add kerneldoc comments documenting them. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-04PM / Domains: Add power-on function using names to identify domainsRafael J. Wysocki
It sometimes is necessary to turn on a given PM domain when only the name of it is known and the domain pointer is not readily available. For this reason, add a new helper function, pm_genpd_name_poweron(), allowing the caller to turn on a PM domain using its name for identification. To avoid code duplication, move the domain lookup code to a separate function. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-04PM / Domains: Make it possible to use names when adding subdomainsRafael J. Wysocki
Add a new helper function, pm_genpd_add_subdomain_names(), allowing the caller to add a subdomain to a generic PM domain using names for domain identification (both domains have to be initialized before). This function is useful for adding subdomains to PM domains whose representations are stored in tables, when the caller doesn't know the indices of the domain to add the subdomain to and of the subdomain itself, but it knows the domains' names. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-04PM / Domains: Make it possible to use domain names when adding devicesRafael J. Wysocki
Add a new helper function __pm_genpd_name_add_device() allowing a device to be added to a (registered) generic PM domain identified by name. Add a wrapper around it, pm_genpd_name_add_device(), passing NULL as the last argument and reorganize pm_domains.h for the new functions to be defined consistently with the existing ones. These functions are useful for adding devices to PM domains whose representations are stored in tables, when the caller doesn't know the index of the domain to add the device to, but it knows the domain's name. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-04PM / Domains: Move syscore flag from subsys data to struct deviceRafael J. Wysocki
The syscore device PM flag is used to mark the devices (belonging to a PM domain) that should never be turned off, except for the system core (syscore) suspend/hibernation and resume stages. That flag is stored in the device's struct pm_subsys_data object whose address is available from struct device. However, in some situations it may be convenient to set that flag before the device is added to a PM domain, so it is better to move it directly to the "power" member of struct device. Then, it can be checked by the routines in drivers/base/power/runtime.c and drivers/base/power/main.c, which is more straightforward. This also reduces the number of dev_gpd_data() invocations in the generic PM domains framework, so the overhead related to the syscore flag is slightly smaller. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2012-09-04PM / Domains: Rename the always_on device flag to syscoreRafael J. Wysocki
The always_on device flag is used to mark the devices (belonging to a PM domain) that should never be turned off, except for the system core (syscore) suspend/hibernation and resume stages. Change name of that flag to "syscore" to better reflect its purpose. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Magnus Damm <damm@opensource.se>
2012-09-04PM / Domains: Add power off/on function for system core suspend stageRafael J. Wysocki
Introduce function pm_genpd_syscore_switch() and two wrappers around it, pm_genpd_syscore_poweroff() and pm_genpd_syscore_poweron(), allowing the callers to let the generic PM domains framework know that the given device is not necessary any more and its PM domain can be turned off (the former) or that the given device will be required immediately, so its PM domain has to be turned on (the latter) during the system core (syscore) stage of system suspend (or hibernation) and resume. These functions will be used for handling devices registered as clock sources and clock event devices that belong to PM domains. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-05PM / Domains: Add device domain data reference counterRafael J. Wysocki
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>
2012-07-03PM / Domains: Add preliminary support for cpuidle, v2Rafael J. Wysocki
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>
2012-05-18PM / Domains: Make it possible to add devices to inactive domainsRafael J. Wysocki
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>
2012-05-05PM / Domains: Cache device stop and domain power off governor results, v3Rafael J. Wysocki
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>
2012-05-01PM / Domains: Rework default domain power off governor function, v2Rafael J. Wysocki
The existing default domain power down governor function for PM domains, default_power_down_ok(), is supposed to check whether or not the PM QoS latency constraints of the devices in the domain will be violated if the domain is turned off by pm_genpd_poweroff(). However, the computations carried out by it don't reflect the definition of the PM QoS latency constrait in Documentation/ABI/testing/sysfs-devices-power. Make default_power_down_ok() follow the definition of the PM QoS latency constrait. In particular, make it only take latencies into account, because it doesn't matter how much time has elapsed since the domain's devices were suspended for the computation. Remove the break_even_ns and power_off_time fields from struct generic_pm_domain, because they are not necessary any more. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-01PM / Domains: Rework default device stop governor function, v2Rafael J. Wysocki
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>
2012-03-24Merge tag 'device-for-3.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull <linux/device.h> avoidance patches from Paul Gortmaker: "Nearly every subsystem has some kind of header with a proto like: void foo(struct device *dev); and yet there is no reason for most of these guys to care about the sub fields within the device struct. This allows us to significantly reduce the scope of headers including headers. For this instance, a reduction of about 40% is achieved by replacing the include with the simple fact that the device is some kind of a struct. Unlike the much larger module.h cleanup, this one is simply two commits. One to fix the implicit <linux/device.h> users, and then one to delete the device.h includes from the linux/include/ dir wherever possible." * tag 'device-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: device.h: audit and cleanup users in main include dir device.h: cleanup users outside of linux/include (C files)
2012-03-16PM / Domains: Introduce "always on" device flagRafael J. Wysocki
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
2012-03-16device.h: audit and cleanup users in main include dirPaul Gortmaker
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>
2012-03-04PM / Domains: Fix include for PM_GENERIC_DOMAINS=n caseMagnus Damm
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>
2012-02-09PM / Domains: Provide a dummy dev_gpd_data() when generic domains are not usedGuennadi Liakhovetski
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>
2012-01-27PM / Domains: Add OF supportThomas Abraham
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>
2011-12-09PM / Domains: Provide an always on power domain governorMark Brown
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>