summaryrefslogtreecommitdiff
path: root/drivers/base/power/domain.c
AgeCommit message (Collapse)Author
2017-06-29PM / Domains: Handle safely genpd_syscore_switch() call on non-genpd deviceKrzysztof Kozlowski
genpd_syscore_switch() had two problems: 1. It silently assumed that device, it is being called for, belongs to generic power domain and used container_of() on its power domain pointer. Such assumption might not be true always. 2. It iterated over list of generic power domains without holding gpd_list_lock mutex thus list could have been modified at the same time. Usage of genpd_lookup_dev() solves both problems as it is safe a call for non-generic power domains and uses mutex when iterating. Reported-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-06-29PM / Domains: Call driver's noirq callbacksMikko Perttunen
Currently genpd installs its own noirq callbacks, but never calls down to the driver's corresponding callbacks. Add these calls. Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-06-28PM / Domains: Constify genpd pointerKrzysztof Kozlowski
Mark pointer to struct generic_pm_domain const (either passed in argument or used localy in a function), whenever it is not modifed by the function itself. Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-06-22PM / Domains: pdd->dev can't be NULL in genpd_dev_pm_qos_notifier()Viresh Kumar
The pm_domain_data (pdd) pointer is set from genpd_alloc_dev_data() and pdd->dev is guaranteed to be valid. There is no need to check pdd and pdd->dev in rest of the code as pdd->dev will always be valid for a non NULL pdd pointer. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-06-13PM / Domains: Allow overriding the ->xlate() callbackThierry Reding
Allow generic power domain providers to override the ->xlate() callback in case the default genpd_xlate_onecell() translation callback is not good enough. One potential use-case for this is to allow generic power domains to be specified by an ID rather than an index. Signed-off-by: Thierry Reding <treding@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Thierry Reding <treding@nvidia.com>
2017-05-09Merge tag 'armsoc-drivers' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC driver updates from Olof Johansson: "Driver updates for ARM SoCs: Reset subsystem, merged through arm-soc by tradition: - Make bool drivers explicitly non-modular - New support for i.MX7 and Arria10 reset controllers PATA driver for Palmchip BK371 (acked by Tejun) Power domain drivers for i.MX (GPC, GPCv2) - Moved out of mach-imx for GPC - Bunch of tweaks, fixes, etc PMC support for Tegra186 SoC detection support for Renesas RZ/G1H and RZ/G1N Move Tegra flow controller driver from mach directory to drivers/soc - (Power management / CPU power driver) Misc smaller tweaks for other platforms" * tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (60 commits) soc: pm-domain: Fix the mangled urls soc: renesas: rcar-sysc: Add support for R-Car H3 ES2.0 soc: renesas: rcar-sysc: Add support for fixing up power area tables soc: renesas: Register SoC device early soc: imx: gpc: add workaround for i.MX6QP to the GPC PD driver dt-bindings: imx-gpc: add i.MX6 QuadPlus compatible soc: imx: gpc: add defines for domain index soc: imx: Add GPCv2 power gating driver dt-bindings: Add GPCv2 power gating driver ARM/clk: move the ICST library to drivers/clk ARM: plat-versatile: remove stale clock header ARM: keystone: Drop PM domain support for k2g soc: ti: Add ti_sci_pm_domains driver dt-bindings: Add TI SCI PM Domains PM / Domains: Do not check if simple providers have phandle cells PM / Domains: Add generic data pointer to genpd data struct soc/tegra: Add initial flowctrl support for Tegra132/210 soc/tegra: flowctrl: Add basic platform driver soc/tegra: Move Tegra flowctrl driver ARM: tegra: Remove unnecessary inclusion of flowctrl header ...
2017-04-04PM / Domains: Do not check if simple providers have phandle cellsDave Gerlach
There is no reason that a platform genpd driver registered using of_genpd_add_provider_simple needs to be constrained to having no cells in the "power-domains" phandle. Currently the genpd framework will fail if any arguments are passed with for a simple provider but the framework does not actually care, so remove the check for phandle argument count. This will allow greater flexibility for genpd providers to use their own arguments that are passed in the phandle and interpret them however they see fit. Acked-by: Kevin Hilman <khilman@baylibre.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Dave Gerlach <d-gerlach@ti.com> Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
2017-03-29PM / Domains: Ignore domain-idle-states that are not compatibleLina Iyer
domain-idle-states property may have phandles to idle state bindings that may not be compatible with idle state definition defined in [1]. Such phandles would just be ignored and not throw and error when read by the domain core. Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-03-29PM / Domains: Don't warn about IRQ safe device for an always on PM domainUlf Hansson
When an IRQ safe device is attached to a no sleep domain, genpd prints a warning once, as to indicate it is a suboptimal configuration from power consumption point of view. However the warning doesn't make sense for an always on domain, since it anyway remains powered on. Therefore, let's change to not print the warning for this configuration. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-03-29PM / Domains: Respect errors from genpd's ->power_off() callbackUlf Hansson
The current code in genpd_sync_power_off(), doesn't care about potential errors being returned from genpd's ->power_off() callback. Obviously this behaviour could lead to problems, such as incorrectly setting the genpd's status to GPD_STATE_POWER_OFF, but also to incorrectly decrease the subdomain count for the masters, which potentially allows them to be powered off in the next recursive call to genpd_sync_power_off(). Let's fix this behaviour by bailing out when the ->power_off() callback returns an error code. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-03-29PM / Domains: Enable users of genpd to specify always on PM domainsUlf Hansson
The current way to implement an always on PM domain consists of returning -EBUSY from the ->power_off() callback. This is a bit different compared to using the always on genpd governor, which prevents the PM domain from being powered off via runtime suspend, but not via system suspend. The approach to return -EBUSY from the ->power_off() callback to support always on PM domains in genpd is suboptimal. That is because it requires genpd to follow the regular execution path of the power off sequence, which ends by invoking the ->power_off() callback. To enable genpd to early abort the power off sequence for always on PM domains, it needs static information about these configurations. Therefore let's add a new genpd configuration flag, GENPD_FLAG_ALWAYS_ON. Users of the new GENPD_FLAG_ALWAYS_ON flag, are by genpd required to make sure the PM domain is powered on before calling pm_genpd_init(). Moreover, users don't need to implement the ->power_off() callback, as genpd doesn't ever invoke it. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-03-29PM / Domains: Clean up code validating genpd's statusUlf Hansson
There exists several similar validations of the genpd->status, against GPD_STATE_ACTIVE and GPD_STATE_POWER_OFF. Let's clean up this code by converting to use a helper macro, genpd_status_on(). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-03-29PM / Domain: remove conditional from error caseViresh Kumar
There is no point running the conditional 'if' statement if the genpd isn't present. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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>