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path: root/drivers/base/power/domain.c
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2017-02-23PM / Domains: Power off masters immediately in the power off sequenceUlf Hansson
Once a subdomain is powered off, genpd queues a power off work for each of the subdomain's corresponding masters, thus postponing the masters to be powered off to a later point. When genpd used intermediate power off states, which was removed in commit ba2bbfbf6307 ("PM / Domains: Remove intermediate states from the power off sequence"), this behaviour made sense, but now it simply doesn't. Genpd can easily try to power off the masters in the same context as the subdomain, of course by acquiring/releasing the lock. Then, let's convert to this behaviour, as it avoids unnecessary works from being queued. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-23PM / Domains: Rename is_async to one_dev_on for genpd_power_off()Ulf Hansson
The parameter name is_async, for genpd_power_off() gives a poor description of its purpose. To clarify, let's rename it to one_dev_on and update the documentation of it in the function header. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-23PM / Domains: Move genpd_power_off() above genpd_power_on()Ulf Hansson
Following changes in genpd_power_on() makes it invoke genpd_power_off(). To enable these changes and avoiding to declare genpd_power_off(), let's move its implementation above genpd_power_on(). In this way, following changes should become easier to review. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-09PM / Domains: Fix asynchronous execution of *noirq() callbacksUlf Hansson
As the PM core may invoke the *noirq() callbacks asynchronously, the current lock-less approach in genpd doesn't work. The consequence is that we may find concurrent operations racing to power on/off the PM domain. As of now, no immediate errors has been reported, but it's probably only a matter time. Therefor let's fix the problem now before this becomes a real issue, by deploying the locking scheme to the relevant functions. Reported-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-08PM / Domains: Correct comment in irq_safe_dev_in_no_sleep_domain()Ulf Hansson
The earlier comment stated that the dev_warn_once() was going to be printed once per device. Let's fix that, as dev_warn_once() is printed only once, no matter of the device. Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-01-27PM / Domains: Rename functions in genpd for power on/offUlf Hansson
Currently the mix of genpd_poweron(), genpd_power_on(), genpd_sync_poweron() and the ->power_on() callback, makes a bit difficult to follow the path of execution. The similar applies to the functions dealing with power off. In a way to improve this understanding, let's do the following renaming: genpd_power_on() -> _genpd_power_on() genpd_poweron() -> genpd_power_on() genpd_sync_poweron() -> genpd_sync_power_on() genpd_power_off() -> _genpd_power_off() genpd_poweroff() -> genpd_power_off() genpd_sync_poweroff() -> genpd_sync_power_off() genpd_poweroff_unused() -> genpd_power_off_unused() Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-31PM / domains: Fix 'may be used uninitialized' build warningAugusto Mecking Caringi
This patch fixes the following gcc warning: drivers/base/power/domain.c: In function ‘genpd_runtime_resume’: drivers/base/power/domain.c:642:14: warning: ‘time_start’ may be used uninitialized in this function [-Wmaybe-uninitialized] elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start) The same problem (in another function in this same file) was fixed in commit d33d5a6c88fc (avoid spurious "may be used uninitialized" warning) Signed-off-by: Augusto Mecking Caringi <augustocaringi@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-25avoid spurious "may be used uninitialized" warningLinus Torvalds
The timer type simplifications caused a new gcc warning: drivers/base/power/domain.c: In function ‘genpd_runtime_suspend’: drivers/base/power/domain.c:562:14: warning: ‘time_start’ may be used uninitialized in this function [-Wmaybe-uninitialized] elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); despite the actual use of "time_start" not having changed in any way. It appears that simply changing the type of ktime_t from a union to a plain scalar type made gcc check the use. The variable wasn't actually used uninitialized, but gcc apparently failed to notice that the conditional around the use was exactly the same as the conditional around the initialization of that variable. Add an unnecessary initialization just to shut up the compiler. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-06PM / Domains: Fix compatible for domain idle stateLina Iyer
Re-using idle state definition provided by arm,idle-state for domain idle states creates a lot of confusion and limits further evolution of the domain idle definition. To keep things clear and simple, define a idle states for domain using a new compatible "domain-idle-state". Fix existing PM domains code to look for the newly defined compatible. Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-30PM / Domains: Do not print PM domain add error message if EPROBE_DEFERGeert Uytterhoeven
EPROBE_DEFER is not an error, hence printing an error message like renesas_irqc e61c0000.interrupt-controller: failed to add to PM domain always-on: -517 may confuse the user. Suppress the error message in case of EPROBE_DEFER to fix this. Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-11PM / Domains: Fix a warning messageDan Carpenter
The first argument of WARN() is the condition, followed by the message. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-27PM / Domains: check for negative return from of_count_phandle_with_args()Colin Ian King
The return from of_count_phandle_with_args can be negative, so we should avoid kcalloc of a negative count of genpd_power_stat structs by sanity checking if count is zero or less. Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Kevin Hilman <khilman@baylibre.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21PM / Domains: Support IRQ safe PM domainsLina Iyer
Generic Power Domains currently support turning on/off only in process context. This prevents the usage of PM domains for domains that could be powered on/off in a context where IRQs are disabled. Many such domains exist today and do not get powered off, when the IRQ safe devices in that domain are powered off, because of this limitation. However, not all domains can operate in IRQ safe contexts. Genpd therefore, has to support both cases where the domain may or may not operate in IRQ safe contexts. Configuring genpd to use an appropriate lock for that domain, would allow domains that have IRQ safe devices to runtime suspend and resume, in atomic context. To achieve domain specific locking, set the domain's ->flag to GENPD_FLAG_IRQ_SAFE while defining the domain. This indicates that genpd should use a spinlock instead of a mutex for locking the domain. Locking is abstracted through genpd_lock() and genpd_unlock() functions that use the flag to determine the appropriate lock to be used for that domain. Domains that have lower latency to suspend and resume and can operate with IRQs disabled may now be able to save power, when the component devices and sub-domains are idle at runtime. The restriction this imposes on the domain hierarchy is that non-IRQ safe domains may not have IRQ-safe subdomains, but IRQ safe domains may have IRQ safe and non-IRQ safe subdomains and devices. Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21PM / Domains: Abstract genpd lockingLina Iyer
Abstract genpd lock/unlock calls, in preparation for domain specific locks added in the following patches. Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21PM / Domains: Save the fwnode in genpd_power_stateLina Iyer
Save the fwnode for the genpd state in the state node. PM Domain clients may use the fwnode to read in the platform specific domain state properties and associate them with the state. Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21PM / Domains: Allow domain power states to be read from DTLina Iyer
This patch allows domains to define idle states in the DT. SoC's can define domain idle states in DT using the "domain-idle-states" property of the domain provider. Add API to read the idle states from DT that can be set in the genpd object. This patch is based on the original patch by Marc Titinger. Signed-off-by: Marc Titinger <mtitinger+renesas@baylibre.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21PM / Domains: Make genpd state allocation dynamicLina Iyer
Allow PM Domain states to be defined dynamically by the drivers. This removes the limitation on the maximum number of states possible for a domain. Suggested-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-24PM / Domains: Rename pm_genpd_sync_poweron|poweroff()Ulf Hansson
These are internal static functions to genpd. Let's conform to the naming rules, by dropping the "pm_" prefix from these. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-24PM / Domains: Don't measure latency of ->power_on|off() during system PMUlf Hansson
Measure latency does by itself contribute to an increased latency, thus we should avoid it when it isn't needed. Currently genpd measures latencies in the system PM phase for the ->power_on|off() callbacks, except in the syscore case when it's not allowed to use ktime_get() as timekeeping may be suspended. Since there should be plenty of occasions during runtime PM to perform these measurements, let's rely on that and drop them from system PM. This will also make it consistent for how measurements are done of the runtime PM callbacks (as those may be invoked during system PM). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-24PM / Domains: Remove redundant system PM callbacksUlf Hansson
In cases when the PM domain haven't assigned a system PM callback, the PM core fall-backs to check for the callback at the driver level instead. This makes it redundant to assign a pm_generic_* helper function to a corresponding system PM callback at a PM domain level. Therefore, let's remove these assignments in pm_genpd_init(). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-24PM / Domains: Simplify detaching a device from its genpdUlf Hansson
There's no need to validate the PM domain by using genpd_lookup_dev() when removing the device via genpd's genpd_dev_pm_detach() function. That's because this function can't be called, unless there is a valid PM domain for the device. To simplify the behaviour, let's move code from pm_genpd_remove_device() into a new internal function, genpd_remove_device(), which is called from pm_genpd_remove_device() and genpd_dev_pm_detach(). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-17PM / Domains: Allow holes in genpd_data.domains arrayTomeu Vizoso
In platforms such as Rockchip's, the array of domains isn't always filled without holes, as which domains are present depend on the particular SoC revision. By allowing holes to be in the array, such SoCs can still use a single set of constants to index the array of power domains. Fixes: 0159ec670763 (PM / Domains: Verify the PM domain is present when adding a provider) Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Acked-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Add support for removing nested PM domains by providerJon Hunter
If a device supports PM domains that are subdomains of another PM domain, then the PM domains should be removed in reverse order to ensure that the subdomains are removed first. Furthermore, if there is more than one provider, then there needs to be a way to remove the domains in reverse order for a specific provider. Add the function of_genpd_remove_last() to remove the last PM domain added by a given PM domain provider and return the generic_pm_domain structure for the PM domain that was removed. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Add support for removing PM domainsJon Hunter
The genpd framework allows users to add PM domains via the pm_genpd_init() function, however, there is no corresponding function to remove a PM domain. For most devices this may be fine as the PM domains are never removed, however, for devices that wish to populate the PM domains from within a driver, having the ability to remove a PM domain if the probing of the device fails or the driver is unloaded is necessary. Add the function pm_genpd_remove() to remove a PM domain by referencing it's generic_pm_domain structure. Note that the bulk of the code that removes the PM domain is placed in a separate local function genpd_remove() (which is called by pm_genpd_remove()). The code is structured in this way to prepare for adding another function to remove a PM domain by provider that will also call genpd_remove(). Note that users of genpd_remove() must call this function with the mutex, gpd_list_lock, held. PM domains can only be removed if the associated provider has been removed, they are not a parent domain to another PM domain and have no devices associated with them. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Store the provider in the PM domain structureJon Hunter
It is possible that a device has more than one provider of PM domains and to support the removal of a PM domain by provider, it is necessary to store a reference to the provider in the PM domain structure. Therefore, store a reference to the firmware node handle in the PM domain structure and populate it when providers (only device-tree based providers are currently supported by PM domains) are registered. Please note that when removing PM domains, it is necessary to verify that the PM domain provider has been removed from the list of providers before the PM domain can be removed. To do this add another member to the PM domain structure that indicates if the provider is present and set this member accordingly when providers are added and removed. Initialise the 'provider' and 'has_provider' members of the generic_pm_domain structure when a PM domains is added by calling pm_genpd_init(). Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Prepare for adding support to remove PM domainsJon Hunter
In order to remove PM domains safely from the list of PM domains, it is necessary to adding locking for the PM domain list around any places where devices or subdomains are added to a PM domain. There are places where a reference to a PM domain is obtained via calling of_genpd_get_from_provider() before adding the device or the subdomain. In these cases a lock for the PM domain list needs to be held around the call to of_genpd_get_from_provider() and the call to add the device/subdomain. To avoid deadlocks by multiple attempts to obtain the PM domain list lock, add functions genpd_add_device() and genpd_add_subdomain() which require the user to hold the PM domain list lock when calling. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Verify the PM domain is present when adding a providerJon Hunter
When a PM domain provider is added, there is currently no way to tell if any PM domains associated with the provider are present. Naturally, the PM domain provider should not be registered if the PM domains have not been added. Nonetheless, verify that the PM domain(s) associated with a provider are present when registering the PM domain provider. This change adds a dependency on the function pm_genpd_present() when CONFIG_PM_GENERIC_DOMAINS_OF is enabled and so ensure this function is available when CONFIG_PM_GENERIC_DOMAINS_OF selected. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Don't expose xlate and provider helper functionsJon Hunter
Functions __of_genpd_xlate_simple(), __of_genpd_xlate_onecell() and __of_genpd_add_provider() are not used outside of the core generic PM domain code. Therefore, reduce the number of APIs exposed by making these static. At the same time don't expose the typedef for genpd_xlate_t either and make this a local definition as well. The functions are renamed to follow the naming conventions for static functions in the generic PM domain core. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Don't expose generic_pm_domain structure to clientsJon Hunter
There should be no need to expose the generic_pm_domain structure to clients and this eliminates the need to implement reference counting for any external reference to a PM domain. Therefore, make the functions pm_genpd_lookup_dev() and of_genpd_get_from_provider() private to the PM domain core. The functions are renamed in accordance with the naming conventions for genpd static functions. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Add new helper functions for device-treeJon Hunter
Ideally, if we are returning a reference to a PM domain via a call to of_genpd_get_from_provider(), then we should keep track of such references via a reference count. The reference count could then be used to determine if a PM domain can be safely removed. Alternatively, it is possible to avoid such external references by providing APIs to access the PM domain and hence, eliminate any calls to of_genpd_get_from_provider(). Add new helper functions for adding a device and a subdomain to a PM domain when using device-tree, so that external calls to of_genpd_get_from_provider() can be removed. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-12PM / Domains: Always enable debugfs support if availableJon Hunter
Debugfs support for PM domains is only enabled if both CONFIG_PM_DEBUG and CONFIG_PM_ADVANCED_DEBUG are enabled. CONFIG_PM_ADVANCED_DEBUG is described as "extra PM attributes in sysfs for low-level debugging/testing" which does not seem related. Given that the debugfs for PM domains only allows users to view the state of the PM domains, always enable debugfs support for PM domains if PM domains and debugfs support is enabled. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-29PM / Domains: Convert pm_genpd_init() to return an error codeUlf Hansson
The are already cases when pm_genpd_init() can fail. Currently we hide the failures instead of propagating an error code, which is a better method. Moreover, to prepare for future changes like moving away from using a fixed array-size of the struct genpd_power_state, to instead dynamically allocate data for it, the pm_genpd_init() API needs to be able to return an error code, as allocation can fail. Current users of the pm_genpd_init() is thus requested to start dealing with error codes. In the transition phase, users will have to live with only error messages being printed to log. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16PM / Domains: Stop/start devices during system PM suspend/resume in genpdUlf Hansson
Not all subsystems/drivers that manages devices attached to a genpd makes use of the pm_runtime_force_suspend|resume() helper functions to deal with system PM suspend/resume. In cases like these and when genpd's ->stop|start() callbacks are used for the device, invoke the pm_runtime_force_suspend|resume() helper functions from genpd's "noirq" system PM callbacks. In this way we make sure to "stop" the device on suspend and to "start" it on resume. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16PM / Domains: Allow runtime PM during system PM phasesUlf Hansson
In cases when a PM domain isn't powered off when genpd's ->prepare() callback is invoked, genpd runtime resumes and disables runtime PM for the device. This behaviour was needed when genpd managed intermediate states during the power off sequence, as to maintain proper low power states of devices during system PM suspend/resume. Commit ba2bbfbf6307 (PM / Domains: Remove intermediate states from the power off sequence), enables genpd to improve its behaviour in that respect. The PM core disables runtime PM at __device_suspend_late() before it calls a system PM "late" callback for a device. When resuming a device, after a corresponding "early" callback has been invoked, the PM core re-enables runtime PM. By changing genpd to allow runtime PM according to the same system PM phases as the PM core, devices can be runtime resumed by their corresponding subsystem/driver when really needed. In this way, genpd no longer need to runtime resume the device from its ->prepare() callback. In most cases that avoids unnecessary and energy- wasting operations of runtime resuming devices that have nothing to do, only to runtime suspend them shortly after. Although, because of changing this behaviour in genpd and due to that genpd powers on the PM domain unconditionally in the system PM resume "noirq" phase, it could potentially cause a PM domain to stay powered on even if it's unused after the system has resumed. To avoid this, schedule a power off work when genpd's system PM ->complete() callback has been invoked for the last device in the PM domain. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16PM / Domains: Remove redundant pm_request_idle() call in genpdUlf Hansson
The PM core increases the runtime PM usage count at the system PM prepare phase. Later when the system resumes, it does a pm_runtime_put() in the complete phase, which in addition to decrementing the usage count, does the equivalent of a pm_request_idle(). Therefore the call to pm_request_idle() from within genpd's ->complete() callback is redundant, so remove it. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16PM / Domains: Remove redundant wrapper functions for system PMUlf Hansson
Due to the previous changes in genpd, which removed the suspend_power_off flag, several of the system PM callbacks no longer do any additional checks but only invoke corresponding pm_generic_* helper functions. To clean up the code, drop these wrapper functions as they have become redundant. Instead, assign the system PM callbacks directly to the pm_generic_*() helper functions. While changing this, it has bocame clear that some of the current system PM callbacks in genpd invoke wrong driver callbacks. For example, the genpd's ->restore() callback invokes pm_generic_resume(), while that should be pm_generic_restore(). Fix that as well. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16PM / Domains: Allow genpd to power on during system PM phasesUlf Hansson
If a PM domain is powered off when the first device starts its system PM prepare phase, genpd prevents any further attempts to power on the PM domain during the following system PM phases. Not until the system PM complete phase is finalized for all devices in the PM domain, genpd again allows it to be powered on. This behaviour needs to be changed, as a subsystem/driver for a device in the same PM domain may still need to be able to serve requests in some of the system PM phases. Accordingly, it may need to runtime resume its device and thus also request the corresponding PM domain to be powered on. To deal with these scenarios, let's make the device operational in the system PM prepare phase by runtime resuming it, no matter if the PM domain is powered on or off. Changing this also enables us to remove genpd's suspend_power_off flag, as it's being used to track this condition. Additionally, we must allow the PM domain to be powered on via runtime PM during the system PM phases. This change also requires a fix in the AMD ACP (Audio CoProcessor) drm driver. It registers a genpd to model the ACP as a PM domain, but unfortunately it's also abuses genpd's "internal" suspend_power_off flag to deal with a corner case at system PM resume. More precisely, the so called SMU block powers on the ACP at system PM resume, unconditionally if it's being used or not. This may lead to that genpd's internal status of the power state, may not correctly reflect the power state of the HW after a system PM resume. Because of changing the behaviour of genpd, by runtime resuming devices in the prepare phase, the AMD ACP drm driver no longer have to deal with this corner case. So let's just drop the related code in this driver. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Acked-by: Maruthi Bayyavarapu <maruthi.bayyavarapu@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-26PM / Domains: Drop unnecessary wakeup code from pm_genpd_prepare()Ulf Hansson
As the PM core already have wakeup management during the system PM phase, it seems reasonable that genpd and its users should be able to rely on that. Therefore let's remove this from pm_genpd_prepare(). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-26PM / Domains: Remove redundant pm_runtime_get|put*() in pm_genpd_prepare()Ulf Hansson
The PM core increases and decreases the runtime PM usage count in the system PM prepare phase. This makes some of the pm_runtime_get|put*() calls in pm_genpd_prepare() redundant, so let's remove them. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-22PM / Domains: Remove ->save|restore_state() callbacksUlf Hansson
As a part of the ongoing consolidation of genpd, it's become questionable whether clients actually needs to be able to assign their own set of ->save|restore_state() callbacks. Currently all users copes fine with the default callbacks, so let's remove the configuration option and stick to the default ones. This enables further clarifications of the related code and let's also rename pm_genpd_default_save|restore_state() into __genpd_runtime_suspend|resume() to apply the rule of static functionnames in genpd. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-22PM / Domains: Rename pm_genpd_runtime_suspend|resume()Ulf Hansson
Follow genpd's rule for names of static functions, by renaming pm_genpd_runtime_suspend|resume() to genpd_runtime_suspend|resume(). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-22PM / Domains: Rename stop_ok to suspend_ok for the genpd governorUlf Hansson
The genpd governor validates the latency constraints to find out whether it's acceptable to runtime suspend a device. Earlier this validation was made to know whether it was okay to invoke the ->stop() callback for the device, hence the governor used the name "stop_ok" for the related variables. To clarify the code around this, let's rename these variables from "stop_ok" to "suspend_ok". Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09PM / Domains: Fix potential NULL pointer dereferenceJon Hunter
In the function of_genpd_get_from_provider(), we never check to see if the argument 'genpdspec' is NULL before dereferencing it. Add error checking to handle any NULL pointers. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09PM / Domains: Fix removal of a subdomainJon Hunter
Commit 30e7a65b3fdb (PM / Domains: Ensure subdomain is not in use before removing) added a test to ensure that a subdomain is not a master to another subdomain or if any devices are using the subdomain before removing. This change incorrectly used the "slave_links" list to determine if the subdomain is a master to another subdomain, where it should have been using the "master_links" list instead. The "slave_links" list will never be empty for a subdomain and so a subdomain can never be removed. Fix this by testing if the "master_links" list is empty instead. Fixes: 30e7a65b3fdb (PM / Domains: Ensure subdomain is not in use before removing) Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09PM / Domains: Propagate start and restore errors during runtime resumeLaurent Pinchart
During runtime resume the return values of the start and restore steps are ignored. As a result drivers are not notified of runtime resume failures and can't propagate them up. Fix it by returning an error if either the start or restore step fails, and clean up properly in the error path. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Acked-by: Kevin Hilman <khilman@baylibre.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09PM / Domains: Join state name and index in debugfs outputGeert Uytterhoeven
For low-power states, the state index is part of the state, hence join them with a hyphen in the /sys/kernel/debug/pm_genpd/pm_genpd_summary output. E.g. "off 0" becomes "off-0". Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-09PM / Domains: Restore alignment of slaves in debugfs outputGeert Uytterhoeven
The slave domains are no longer aligned with the table header in the /sys/kernel/debug/pm_genpd/pm_genpd_summary output. Worse, the alignment differs depending on the actual name of the state. Format the state name and index into a buffer, and print that like before to restore alignment. Use "%u" for unsigned int while we're at it. Fixes: fc5cbf0c94b6f7fd (PM / Domains: Support for multiple states) Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-15PM / Domains: remove old power on/off latenciesAxel Haslam
Now that all known users have been converted to use state latencies, we can remove the latency field in the generic_pm_domain structure. Signed-off-by: Axel Haslam <ahaslam+renesas@baylibre.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-15PM / Domains: Support for multiple statesAxel Haslam
Some hardware (eg. OMAP), has the ability to enter different low power modes for a given power domain. This allows for more fine grained control over the power state of the platform. As a typical example, some registers of the hardware may be implemented with retention flip-flops and be able to retain their state at lower voltages allowing for faster on/off latencies and an increased window of opportunity to enter an intermediate low power state other than "off" When trying to set a power domain to off, the genpd governor will choose the deepest state that will respect the qos constraints of all the devices and sub-domains on the power domain. The state chosen by the governor is saved in the "state_idx" field of the generic_pm_domain structure and shall be used by the power_off and power_on callbacks to perform the necessary actions to set the power domain into (and out of) the state indicated by state_idx. States must be declared in ascending order from shallowest to deepest, deepest meaning the state which takes longer to enter and exit. For platforms that don't declare any states, a single a single "off" state is used. Once all platforms are converted to use the state array, the legacy on/off latencies will be removed. [ Lina: Modified genpd state initialization and remove use of save_state_latency_ns in genpd timing data ] Suggested-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Axel Haslam <ahaslam+renesas@baylibre.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-03PM / Domains: Silence compiler warning for an unused functionUlf Hansson
The only remaining caller of genpd_poweron() is conditionally compiled based on CONFIG_PM_GENERIC_DOMAINS_OF, so we get a warning when that is unset. By moving the locking/unlocking of the genpd outside genpd_poweron(), thus to the caller, genpd_poweron() becomes redundant. Within this context let's then rename the wrapper function, __genpd_poweron(), to genpd_poweron() as it will then be consistent with its friend genpd_poweroff(). This change silence the warning about the unused function. Reported-by: Arnd Bergmann <arnd@arndb.de> Fixes: ea823c7cbffa "PM / Domains: Remove pm_genpd_poweron() API" Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: 4.4+ <stable@vger.kernel.org> # 4.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>