linux/drivers/base
Lina Iyer d716f4798f PM / Domains: Support IRQ safe PM domains
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>
2016-10-21 22:20:56 +02:00
..
power PM / Domains: Support IRQ safe PM domains 2016-10-21 22:20:56 +02:00
regmap Merge remote-tracking branches 'regmap/topic/core' and 'regmap/topic/debugfs' into regmap-next 2016-10-04 05:17:12 +02:00
attribute_container.c attribute_container: Fix typo 2016-08-31 15:13:56 +02:00
base.h PM / sleep: prohibit devices probing during suspend/hibernation 2015-11-30 14:47:22 +01:00
bus.c driver core: bus: use to_subsys_private and to_device_private_bus 2016-02-09 17:25:27 -08:00
cacheinfo.c cpu/cacheinfo: Fix teardown path 2015-09-17 06:06:54 -07:00
class.c class_find_device: fix reference to argument "match" 2015-09-29 15:23:14 +02:00
component.c Merge 4.5-rc4 into driver-core-next 2016-02-14 14:29:55 -08:00
container.c ACPI / hotplug / driver core: Handle containers in a special way 2013-12-29 15:25:48 +01:00
core.c Driver core patches for 4.9-rc1 2016-10-03 20:03:24 -07:00
cpu.c cpu: clean up register_cpu func 2016-08-31 15:19:55 +02:00
dd.c device core: Remove deprecated create_singlethread_workqueue 2016-09-02 15:08:02 +02:00
devcoredump.c devcoredump: add scatterlist support 2016-04-15 11:20:32 -07:00
devres.c devm: make allocations numa aware by default 2015-10-09 17:00:33 -04:00
devtmpfs.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
dma-coherent.c drivers: dma-coherent: Move spinlock in dma_alloc_from_coherent() 2016-09-28 17:53:16 +02:00
dma-contiguous.c driver core update for 4.4-rc1 2015-11-04 21:50:37 -08:00
dma-mapping.c drivers/base dmam_declare_coherent_memory leaks 2016-08-31 15:19:55 +02:00
driver.c driver core: add missing blank line after declaration 2015-03-25 14:36:30 +01:00
firmware_class.c firmware: support loading into a pre-allocated buffer 2016-08-02 19:35:10 -04:00
firmware.c
hypervisor.c
init.c drivers: of/base: move of_init to driver_init 2015-05-26 19:55:56 -07:00
isa.c isa: Call isa_bus_init before dependent ISA bus drivers register 2016-06-17 20:47:11 -07:00
Kconfig driver core: add test of driver remove calls during probe 2016-08-31 15:13:55 +02:00
Makefile isa: Allow ISA-style drivers on modern systems 2016-06-17 20:21:12 -07:00
map.c drivers: base: map: Use kmalloc_array instead of kmalloc 2015-03-25 14:35:08 +01:00
memory.c memory-hotplug: fix store_mem_state() return value 2016-10-07 18:46:28 -07:00
module.c base: make module_create_drivers_dir race-free 2016-06-15 19:21:31 -07:00
node.c treewide: replace obsolete _refok by __ref 2016-08-02 17:31:41 -04:00
pinctrl.c driver: base: pinctrl: return error from pinctrl_bind_pins() 2016-09-13 23:02:59 +02:00
platform-msi.c genirq/msi: Add cpumask allocation to alloc_msi_entry 2016-09-14 22:11:08 +02:00
platform.c driver-core: platform: Catch errors from calls to irq_get_irq_data 2016-09-27 12:30:37 +02:00
property.c device property: Add function to search for named child of device 2016-06-26 12:39:03 +01:00
soc.c base: soc: make it explicitly non-modular 2016-08-31 15:13:56 +02:00
syscore.c genirq: Simplify wakeup mechanism 2014-09-01 13:48:59 +02:00
topology.c topology/sysfs: provide drawer id and siblings attributes 2016-06-13 15:58:27 +02:00
transport_class.c