The device PM subsystem _depends_ on device, not vice-versa. Devices
only hold a reference to struct pm_device now, and initialize this
reference with the value provided in Z_DEVICE_DEFINE. This requirement
can be solved with a forward struct declaration, meaning there is no
need to include device PM headers.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
The macro has been moved to the pm/device.h header, being now called by
the Z_PM_DEVICE_DEFINE macro. This means that a slot will only be
created if the device uses PM, thus reducing memory usage.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Devices PM callback receive an action and not a state. Add a new API
that receives an action instead of a state.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Replace PM_STATE_LEN with PM_STATE_COUNT, so that number of states is
automatically computed.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
It is well known that PM subsystem has never been optimized in terms of
resource usage. The situation is particularly bad in case the PM runtime
API is enabled. What this patch does is to move the responsability of PM
resource definition to the device like this:
- Device is responsible to define PM resources, using a new set of
macros: PM_DEVICE_*DEFINE().
- DEVICE_*DEFINE macro accepts a reference to the device PM state, which
can be obtained using PM_DEVICE_*REF() set of macros. This
allows device to initialize the dev->pm reference.
This method decouples a bit more PM from devices since devices just keep
a reference to the device PM state. It also means that future PM changes
will have less chances to impact all devices, but only devices that
support PM.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Change pm_power_state_force to receive which cpu the state should be
forced. Also, it changed the API behavior to force the given state only
when the idle thread for that core is executed.
In a multicore environment force arbitrarily a core to suspend is not
safe because the kernel cannot infer what that cpu is running and how it
impacts the overall system, for example, if it is holding a lock that is
required by a thread that is running in another cpu.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Rename the macro used to initialize the runtime fields to
Z_PM_DEVICE_RUNTIME_INIT (emphasize it is internal and follows parent
macro naming).
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Some macros were helpers for the state initializers (e.g. to assist
UTIL_LISTIFY). In order to make the API more clear, they have been
prefixed with Z_ to emphasize they are internal and they have also been
removed from documentation.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Z_PM_DEVICE_INIT is used as a static initializer, so all non-specified
fields will already be set to zero.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Add a dummy implementation for the wakeup API, so that it can still be
used when no PM_DEVICE is enabled.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
The PM flags are only used internally, so there is no need to include
them in the documentation.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Document the deprecated functions and macros, tag them with @deprecated
command to inform about the replacement.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
- Add a new `subsys_pm` group, part of `subsys`
- Improve group naming
- Include conditional code using __DOXYGEN__, it allows to have better
control of inclusion.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Move all PM device runtime API calls from pm_device* to the
pm_device_runtime* namespace.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
This patch refactors the runtime API to make it more clear and simple.
Relevant changes:
- API uses the action callback in a direct manner, avoiding unnecessary
overhead.
- API documentation has been improved to include detailed return error
codes.
- pm_runtime_disable() is now synchronous (to simplify possible error
paths) and returns error in case it fails. It is also safe to disable
in pre-kernel now.
- pm_runtime_put(_async)() will return -EALREADY if called with usage
count at zero (result of an unbalanced get/put call sequence)
- A transitional state has been added back. This makes code more
readable, and avoids using atomics (not required).
TODO:
- Solve in a better manner the asynchronous suspend error path (now
"solved" using asserts).
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
After the removal of pm_device_get_async, the pm_device_wait API has
become redundant. Its usage after pm_device_put_async should not be
considered a valid usecase, since after that call what will happen is a
pm_device_get (which is blocking).
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
As of today there is no clear usage of asynchronous gets, since in
general, a resume operation should be synchronous (we are about to use
the device immediately after resuming it). Removing this API simplifies
the runtime implementation in a significant way (refer to future
commits).
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
As discussed in issues/38619, this commit aims to simplify device
power management. It was removed PM_DEVICE_SATE_LOW_POWER.
The power subsystem now doesn't need to figure out which device state to
use of a given system power state. It just suspend and resume devices.
Devices now just need to respond to ACTIVE and SUSPEND and OFF actions
and they are free to use any particular substate they have when the
subsystem asks to suspend. They also don't need to worry about states
transitions (unless they have multiple substates) because the system
will just request them to suspend if they are active and vice-versa.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
rebase
Add a function that can be used by device drivers to know
what will be next power state used by the SoC.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Uses the stats subsys to provide simple but useful debugging stats for
power management state changes and timing.
Removes the no longer needed PM_DEBUG config option
Replaces the use of PM_DEBUG for a test clock output pin for mec1501 and
adds in its place an SoC Kconfig option to enable it.
Adds a STATS_SET macro for assigning a value to a stat group field
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
- Rename to "action" to make its purpose more clear
- Use the _cb suffix to align with naming used for callbacks in other
areas.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
z_pm_save_idle_exit() is only declared if CONFIG_PM is enabled but
unconditionally defined. Just move it around in the header to always
be declared.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Create stubs for when the subsystem is not compiled. Some drivers need
to use constraints when are in the middle of a transaction to avoid
the system to sleep. As the same driver may be used in a target that
does not support power management, they have to conditionally (#if
CONFIG_PM) call these functions, these stubs avoid this regular problem.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
PM_DEVICE_STATE_RESUMING and PM_DEVICE_STATE_SUSPENDING
are transitional states and are only used in device runtime. Remove it
and use device flag to keep track of a transition.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
The Z_DEVICE_STATE_DEFINE macro was conditioned by CONFIG_PM_DEVICE.
This is a problem if one day we have other conditional fields in the
device state field that need to be initialized. The approach has been
changed to have an always existing initializer for the PM field, that is
a no-op if device PM is not enabled.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Create a utility macro to initialize struct pm_device. The initializer
is kept in the pm/device.h header.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Introduce a new API to allow devices capable of wake up the system
register themselves was wake up sources. This permits applications to
select the most appropriate way to wake up the system when it is
suspended.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Just using a simple atomic for flags instead of using an array.
While is neat using ATOMIC_DEFINE for future proof. The reality is
that it brings some problem for the wakeup source implementation
that needs to statically initialize it during the device definition.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Add support for FORCE_SUSPEND and LOW_POWER actions. Even though these
actions have no clear meaning, they are added for compatibility until
their associated states are discussed. Their usage in new code should be
discouraged until the associated states are clarified.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
