linux.git/drivers/base/power, branch v4.9-rc2 Linux kernel source tree Merge branches 'pm-cpuidle', 'pm-opp' and 'pm-avs' 2016-10-01T23:43:16+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2016-10-01T23:43:16+00:00 e35db92b4f53cad816af25c1a5f8be414e0de9fc * pm-cpuidle: ARM: cpuidle: Fix error return code * pm-opp: PM / OPP: Don't support OPP if it provides supported-hw but platform does not PM / OPP: avoid maybe-uninitialized warning * pm-avs: PM / AVS: SmartReflex: Neaten logging 
* pm-cpuidle:
  ARM: cpuidle: Fix error return code

* pm-opp:
  PM / OPP: Don't support OPP if it provides supported-hw but platform does not
  PM / OPP: avoid maybe-uninitialized warning

* pm-avs:
  PM / AVS: SmartReflex: Neaten logging
Merge branch 'pm-domains' 2016-10-01T23:41:29+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2016-10-01T23:41:29+00:00 2dc3c72cd0a3ea85b8b7ae469904cfc24af1de60 * pm-domains: PM / Domains: Rename pm_genpd_sync_poweron|poweroff() PM / Domains: Don't measure latency of ->power_on|off() during system PM PM / Domains: Remove redundant system PM callbacks PM / Domains: Simplify detaching a device from its genpd PM / Domains: Allow holes in genpd_data.domains array PM / Domains: Add support for removing nested PM domains by provider PM / Domains: Add support for removing PM domains PM / Domains: Store the provider in the PM domain structure PM / Domains: Prepare for adding support to remove PM domains PM / Domains: Verify the PM domain is present when adding a provider PM / Domains: Don't expose xlate and provider helper functions PM / Domains: Don't expose generic_pm_domain structure to clients staging: board: Remove calls to of_genpd_get_from_provider() ARM: EXYNOS: Remove calls to of_genpd_get_from_provider() PM / Domains: Add new helper functions for device-tree PM / Domains: Always enable debugfs support if available 
* pm-domains:
  PM / Domains: Rename pm_genpd_sync_poweron|poweroff()
  PM / Domains: Don't measure latency of ->power_on|off() during system PM
  PM / Domains: Remove redundant system PM callbacks
  PM / Domains: Simplify detaching a device from its genpd
  PM / Domains: Allow holes in genpd_data.domains array
  PM / Domains: Add support for removing nested PM domains by provider
  PM / Domains: Add support for removing PM domains
  PM / Domains: Store the provider in the PM domain structure
  PM / Domains: Prepare for adding support to remove PM domains
  PM / Domains: Verify the PM domain is present when adding a provider
  PM / Domains: Don't expose xlate and provider helper functions
  PM / Domains: Don't expose generic_pm_domain structure to clients
  staging: board: Remove calls to of_genpd_get_from_provider()
  ARM: EXYNOS: Remove calls to of_genpd_get_from_provider()
  PM / Domains: Add new helper functions for device-tree
  PM / Domains: Always enable debugfs support if available
PM / OPP: Don't support OPP if it provides supported-hw but platform does not 2016-09-26T13:13:31+00:00 Dave Gerlach d-gerlach@ti.com 2016-09-23T20:07:47+00:00 a4ee4545932d4b26ec0c190f2ce265de79990c7a The OPP framework allows each OPP to set a opp-supported-hw property which provides values that are matched against supported_hw values provided by the platform to limit support for certain OPPs on specific hardware. Currently, if the platform does not set supported_hw values, all OPPs are interpreted as supported, even if they have provided their own opp-supported-hw values. If an OPP has provided opp-supported-hw, it is indicating that there is some specific hardware configuration it is supported by. These constraints should be honored, and if no supported_hw has been provided by the platform, there is no way to determine if that OPP is actually supported, so it should be marked as not supported. Signed-off-by: Dave Gerlach <d-gerlach@ti.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
The OPP framework allows each OPP to set a opp-supported-hw property
which provides values that are matched against supported_hw values
provided by the platform to limit support for certain OPPs on specific
hardware. Currently, if the platform does not set supported_hw values,
all OPPs are interpreted as supported, even if they have provided their
own opp-supported-hw values.

If an OPP has provided opp-supported-hw, it is indicating that there is
some specific hardware configuration it is supported by. These constraints
should be honored, and if no supported_hw has been provided by the
platform, there is no way to determine if that OPP is actually supported,
so it should be marked as not supported.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / Domains: Rename pm_genpd_sync_poweron|poweroff() 2016-09-23T23:54:29+00:00 Ulf Hansson ulf.hansson@linaro.org 2016-09-21T13:38:53+00:00 eefdee07074db61764408583a23e96cf60d5a0a7 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> 
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>
PM / Domains: Don't measure latency of ->power_on|off() during system PM 2016-09-23T23:54:29+00:00 Ulf Hansson ulf.hansson@linaro.org 2016-09-21T13:38:52+00:00 adb560b3ee395ac9688a93582d805edec4c3d3e7 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> 
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>
PM / Domains: Remove redundant system PM callbacks 2016-09-23T23:54:28+00:00 Ulf Hansson ulf.hansson@linaro.org 2016-09-21T13:38:51+00:00 294f47ffd55c3710c6f8ca1122e0424f045a099c 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> 
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>
PM / Domains: Simplify detaching a device from its genpd 2016-09-23T23:54:28+00:00 Ulf Hansson ulf.hansson@linaro.org 2016-09-21T13:38:50+00:00 85168d56cc8603963cfdda1e2b9e8f9b68aef867 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> 
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>
PM / OPP: avoid maybe-uninitialized warning 2016-09-16T22:58:00+00:00 Arnd Bergmann arnd@arndb.de 2016-09-15T15:38:38+00:00 4df27c91893fd13eaa30e9b0bca74f317816f428 When CONFIG_OPTIMIZE_INLINING is set and we are building with -Wmaybe-uninitialized enabled, we can get a warning for the opp core driver: drivers/base/power/opp/core.c: In function 'dev_pm_opp_set_rate': drivers/base/power/opp/core.c:560:8: warning: 'ou_volt_min' may be used uninitialized in this function [-Wmaybe-uninitialized] This has only now appeared as a result of commit 797da5598f3a ("PM / devfreq: Add COMPILE_TEST for build coverage"), which makes the driver visible in some configurations that didn't have it before. The warning is a false positive that I got with gcc-6.1.1, but there is a simple workaround in removing the local variables that we get warnings for (all three are affected depending on the configuration). This also makes the code easier to read. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
When CONFIG_OPTIMIZE_INLINING is set and we are building with -Wmaybe-uninitialized
enabled, we can get a warning for the opp core driver:

drivers/base/power/opp/core.c: In function 'dev_pm_opp_set_rate':
drivers/base/power/opp/core.c:560:8: warning: 'ou_volt_min' may be used uninitialized in this function [-Wmaybe-uninitialized]

This has only now appeared as a result of commit 797da5598f3a ("PM / devfreq:
Add COMPILE_TEST for build coverage"), which makes the driver visible in
some configurations that didn't have it before.

The warning is a false positive that I got with gcc-6.1.1, but there is
a simple workaround in removing the local variables that we get warnings
for (all three are affected depending on the configuration). This also
makes the code easier to read.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / Domains: Allow holes in genpd_data.domains array 2016-09-16T22:56:34+00:00 Tomeu Vizoso tomeu.vizoso@collabora.com 2016-09-15T12:05:23+00:00 609bed67bd8f72981faba75d80b3b48d746b7206 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> 
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>
PM / runtime: Use _rcuidle for runtime suspend tracepoints 2016-09-16T00:59:58+00:00 Paul E. McKenney paulmck@linux.vnet.ibm.com 2016-04-26T17:42:25+00:00 778935778c3b88e5152a88765850009006ef2e32 Further testing with false negatives suppressed by commit 293e2421fe25 ("rcu: Remove superfluous versions of rcu_read_lock_sched_held()") identified a few more unprotected uses of RCU from the idle loop. Because RCU actively ignores idle-loop code (for energy-efficiency reasons, among other things), using RCU from the idle loop can result in too-short grace periods, in turn resulting in arbitrary misbehavior. The affected function is rpm_suspend(). The resulting lockdep-RCU splat is as follows: ------------------------------------------------------------------------ Warning from omap3 =============================== [ INFO: suspicious RCU usage. ] 4.6.0-rc5-next-20160426+ #1112 Not tainted ------------------------------- include/trace/events/rpm.h:63 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 RCU used illegally from extended quiescent state! 1 lock held by swapper/0/0: #0: (&(&dev->power.lock)->rlock){-.-...}, at: [<c052ee24>] __pm_runtime_suspend+0x54/0x84 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1112 Hardware name: Generic OMAP36xx (Flattened Device Tree) [<c0110308>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) [<c010c3a8>] (show_stack) from [<c047fec8>] (dump_stack+0xb0/0xe4) [<c047fec8>] (dump_stack) from [<c052d7b4>] (rpm_suspend+0x604/0x7e4) [<c052d7b4>] (rpm_suspend) from [<c052ee34>] (__pm_runtime_suspend+0x64/0x84) [<c052ee34>] (__pm_runtime_suspend) from [<c04bf3bc>] (omap2_gpio_prepare_for_idle+0x5c/0x70) [<c04bf3bc>] (omap2_gpio_prepare_for_idle) from [<c01255e8>] (omap_sram_idle+0x140/0x244) [<c01255e8>] (omap_sram_idle) from [<c0126b48>] (omap3_enter_idle_bm+0xfc/0x1ec) [<c0126b48>] (omap3_enter_idle_bm) from [<c0601db8>] (cpuidle_enter_state+0x80/0x3d4) [<c0601db8>] (cpuidle_enter_state) from [<c0183c74>] (cpu_startup_entry+0x198/0x3a0) [<c0183c74>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8) [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c) ------------------------------------------------------------------------ Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Guenter Roeck <linux@roeck-us.net> [ rjw: Subject ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Further testing with false negatives suppressed by commit 293e2421fe25
("rcu: Remove superfluous versions of rcu_read_lock_sched_held()")
identified a few more unprotected uses of RCU from the idle loop.
Because RCU actively ignores idle-loop code (for energy-efficiency
reasons, among other things), using RCU from the idle loop can result
in too-short grace periods, in turn resulting in arbitrary misbehavior.

The affected function is rpm_suspend().

The resulting lockdep-RCU splat is as follows:

------------------------------------------------------------------------

Warning from omap3

===============================
[ INFO: suspicious RCU usage. ]
4.6.0-rc5-next-20160426+ #1112 Not tainted
-------------------------------
include/trace/events/rpm.h:63 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
1 lock held by swapper/0/0:
 #0:  (&(&dev->power.lock)->rlock){-.-...}, at: [<c052ee24>] __pm_runtime_suspend+0x54/0x84

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1112
Hardware name: Generic OMAP36xx (Flattened Device Tree)
[<c0110308>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
[<c010c3a8>] (show_stack) from [<c047fec8>] (dump_stack+0xb0/0xe4)
[<c047fec8>] (dump_stack) from [<c052d7b4>] (rpm_suspend+0x604/0x7e4)
[<c052d7b4>] (rpm_suspend) from [<c052ee34>] (__pm_runtime_suspend+0x64/0x84)
[<c052ee34>] (__pm_runtime_suspend) from [<c04bf3bc>] (omap2_gpio_prepare_for_idle+0x5c/0x70)
[<c04bf3bc>] (omap2_gpio_prepare_for_idle) from [<c01255e8>] (omap_sram_idle+0x140/0x244)
[<c01255e8>] (omap_sram_idle) from [<c0126b48>] (omap3_enter_idle_bm+0xfc/0x1ec)
[<c0126b48>] (omap3_enter_idle_bm) from [<c0601db8>] (cpuidle_enter_state+0x80/0x3d4)
[<c0601db8>] (cpuidle_enter_state) from [<c0183c74>] (cpu_startup_entry+0x198/0x3a0)
[<c0183c74>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
[<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)

------------------------------------------------------------------------

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>