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path: root/drivers/cpuidle/dt_idle_states.c
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2017-06-12cpuidle: dt: Add missing 'of_node_put()'Christophe Jaillet
'of_node_put()' should be called on pointer returned by 'of_parse_phandle()' when done. In this function this is done in all path except this 'continue', so add it. Fixes: 97735da074fd (drivers: cpuidle: Add status property to ARM idle states) Signed-off-by: Christophe Jaillet <christophe.jaillet@wanadoo.fr> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-23cpuidle: dt: assign ->enter_freeze to same as ->enter callback functionSudeep Holla
enter_freeze() callback is expected atleast to do the same as enter() but it has to guarantee that interrupts aren't enabled at any point in its execution, as the tick is frozen. CPUs execute ->enter_freeze with the local tick or entire timekeeping suspended, so it must not re-enable interrupts at any point (even temporarily) or attempt to change states of clock event devices. It will be called when the system goes to suspend-to-idle and will reduce power usage because CPUs won't be awaken for unnecessary IRQs (i.e. woken up only on IRQs from "wakeup sources") We can reuse the same code for both the enter() and enter_freeze() callbacks as along as they don't re-enable interrupts. Only "coupled" cpuidle mechanism enables interrupts and doing that with timekeeping suspended is generally not safe. Since this generic DT based idle driver doesn't support "coupled" states, it is safe to assume that the interrupts are not re-enabled. This patch assign enter_freeze to same as enter callback function which helps to save power without any intermittent spurious wakeups from suspend-to-idle. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-21Merge back earlier cpuidle material for 3.19-rc1.Rafael J. Wysocki
Conflicts: drivers/cpuidle/dt_idle_states.c
2014-11-19drivers: cpuidle: Add idle-state-name description to ARM idle statesLorenzo Pieralisi
On ARM machines, where generally speaking the idle state numbering has no fixed and standard meaning it is useful to provide a description of the idle state inner workings for benchmarking and monitoring purposes. This patch adds a property to the idle states bindings that if present gives platform firmware a means of describing the idle state and export the string description to user space. The patch updates the DT parsing code accordingly to take the description, if present, into consideration. Acked-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-11-19drivers: cpuidle: Add status property to ARM idle statesLorenzo Pieralisi
On some platforms the device tree bindings must provide the kernel with a status flag for idle states, that defines whether the idle state is operational or not in the current configuration. This patch adds a status property to the ARM idle states compliant with ePAPR v1.1 and updates the DT parsing code accordingly. Acked-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-11-12cpuidle: Invert CPUIDLE_FLAG_TIME_VALID logicDaniel Lezcano
The only place where the time is invalid is when the ACPI_CSTATE_FFH entry method is not set. Otherwise for all the drivers, the time can be correctly measured. Instead of duplicating the CPUIDLE_FLAG_TIME_VALID flag in all the drivers for all the states, just invert the logic by replacing it by the flag CPUIDLE_FLAG_TIME_INVALID, hence we can set this flag only for the acpi idle driver, remove the former flag from all the drivers and invert the logic with this flag in the different governor. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-25drivers: cpuidle: implement DT based idle states infrastructureLorenzo Pieralisi
On most common ARM systems, the low-power states a CPU can be put into are not discoverable in HW and require device tree bindings to describe power down suspend operations and idle states parameters. In order to enable DT based idle states and configure idle drivers, this patch implements the bulk infrastructure required to parse the device tree idle states bindings and initialize the corresponding CPUidle driver states data. The parsing API accepts a start index that defines the first idle state that should be initialized by the parsing code in order to give new and legacy driver flexibility over which states should be parsed using the new DT mechanism. The idle states node(s) is obtained from the phandle list of the first cpu in the driver cpumask; the kernel checks that the idle state node phandle is the same for all CPUs in the driver cpumask before declaring the idle state as valid and start parsing its content. The idle state enter function pointer is initialized through DT match structures passed in by the CPUidle driver, so that ARM legacy code can cope with platform specific idle entry method based on compatible string matching and the code used to initialize the enter function pointer can be moved to the DT generic layer. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>