linux-toradex.git/drivers/cpuidle, branch v4.4.93

ARM: cpuidle: Fix error return code

2016-10-16T15:36:15+00:00

commit af48d7bc3756a0cd882d65bff14ab39746ba57fe upstream.

We know that 'ret = 0' because it has been tested a few lines above.
So, if 'kzalloc' fails, 0 will be returned instead of an error code.
Return -ENOMEM instead.

Fixes: a0d46a3dfdc3 ("ARM: cpuidle: Register per cpuidle device")
Signed-off-by: Christophe Jaillet 
Acked-by: Lorenzo Pieralisi 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

cpuidle: Fix cpuidle_state_is_coupled() argument in cpuidle_enter()

2016-06-08T01:14:34+00:00

commit e7387da52028b072489c45efeb7a916c0205ebd2 upstream.

Commit 0b89e9aa2856 (cpuidle: delay enabling interrupts until all
coupled CPUs leave idle) rightfully fixed a regression by letting
the coupled idle state framework to handle local interrupt enabling
when the CPU is exiting an idle state.

The current code checks if the idle state is coupled and, if so, it
will let the coupled code to enable interrupts. This way, it can
decrement the ready-count before handling the interrupt. This
mechanism prevents the other CPUs from waiting for a CPU which is
handling interrupts.

But the check is done against the state index returned by the back
end driver's ->enter functions which could be different from the
initial index passed as parameter to the cpuidle_enter_state()
function.

 entered_state = target_state->enter(dev, drv, index);

 [ ... ]

 if (!cpuidle_state_is_coupled(drv, entered_state))
	local_irq_enable();

 [ ... ]

If the 'index' is referring to a coupled idle state but the
'entered_state' is *not* coupled, then the interrupts are enabled
again. All CPUs blocked on the sync barrier may busy loop longer
if the CPU has interrupts to handle before decrementing the
ready-count. That's consuming more energy than saving.

Fixes: 0b89e9aa2856 (cpuidle: delay enabling interrupts until all coupled CPUs leave idle)
Signed-off-by: Daniel Lezcano 
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

cpuidle: Indicate when a device has been unregistered

2016-06-08T01:14:34+00:00

commit c998c07836f985b24361629dc98506ec7893e7a0 upstream.

Currently the 'registered' member of the cpuidle_device struct is set
to 1 during cpuidle_register_device. In this same function there are
checks to see if the device is already registered to prevent duplicate
calls to register the device, but this value is never set to 0 even on
unregister of the device. Because of this, any attempt to call
cpuidle_register_device after a call to cpuidle_unregister_device will
fail which shouldn't be the case.

To prevent this, set registered to 0 when the device is unregistered.

Fixes: c878a52d3c7c (cpuidle: Check if device is already registered)
Signed-off-by: Dave Gerlach 
Acked-by: Daniel Lezcano 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

ARM: cpuidle: Pass on arm_cpuidle_suspend()'s return value

2016-05-11T09:21:19+00:00

commit 625fe4f8ffc1b915248558481bb94249f6bd411c upstream.

arm_cpuidle_suspend() may return -EOPNOTSUPP, or any value returned
by the cpu_ops/cpuidle_ops suspend call. arm_enter_idle_state() doesn't
update 'ret' with this value, meaning we always signal success to
cpuidle_enter_state(), causing it to update the usage counters as if we
succeeded.

Fixes: 191de17aa3c1 ("ARM64: cpuidle: Replace cpu_suspend by the common ARM/ARM64 function")
Signed-off-by: James Morse 
Acked-by: Lorenzo Pieralisi 
Acked-by: Daniel Lezcano 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

cpuidle: mvebu: disable the bind/unbind attributes and use builtin_platform_driver

2015-10-23T10:40:48+00:00

As the driver doesn't support unbinding, nor does it support arbitary
binding of devices, disable the bind/unbind attributes for this driver.
Also, as the driver has no remove function, it can never be modular,
so use builtin_platform_driver() to avoid the module exit boilerplate.

Signed-off-by: Russell King 
Signed-off-by: Daniel Lezcano

cpuidle: mvebu: clean up multiple platform drivers

2015-10-23T10:40:47+00:00

There's no need to use multiple platform drivers, especially when we
want to do something different in the probe, but we still use a common
probe function.

We can use the platform ID system to only register one platform driver,
but have it match several devices, and give us the CPU idle driver via
the ID's driver_data.

Signed-off-by: Russell King 
Signed-off-by: Daniel Lezcano

Merge tag 'pm+acpi-4.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2015-09-12T02:11:06+00:00

Pull more power management and ACPI updates from Rafael Wysocki:
 "These are mostly fixes and cleanups on top of the previous PM+ACPI
  pull request (cpufreq core and drivers, cpuidle, generic power domains
  framework).  Some of them didn't make to that pull request and some
  fix issues introduced by it.

  The only really new thing is the support for suspend frequency in the
  cpufreq-dt driver, but it is needed to fix an issue with Exynos
  platforms.

  Specifics:

   - build fix for the new Mediatek MT8173 cpufreq driver (Guenter
     Roeck).

   - generic power domains framework fixes (power on error code path,
     subdomain removal) and cleanup of a deprecated API user (Geert
     Uytterhoeven, Jon Hunter, Ulf Hansson).

   - cpufreq-dt driver fixes including two fixes for bugs related to the
     new Operating Performance Points Device Tree bindings introduced
     recently (Viresh Kumar).

   - suspend frequency support for the cpufreq-dt driver (Bartlomiej
     Zolnierkiewicz, Viresh Kumar).

   - cpufreq core cleanups (Viresh Kumar).

   - intel_pstate driver fixes (Chen Yu, Kristen Carlson Accardi).

   - additional sanity check in the cpuidle core (Xunlei Pang).

   - fix for a comment related to CPU power management (Lina Iyer)"

* tag 'pm+acpi-4.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  intel_pstate: fix PCT_TO_HWP macro
  intel_pstate: Fix user input of min/max to legal policy region
  PM / OPP: Return suspend_opp only if it is enabled
  cpufreq-dt: add suspend frequency support
  cpufreq: allow cpufreq_generic_suspend() to work without suspend frequency
  PM / OPP: add dev_pm_opp_get_suspend_opp() helper
  staging: board: Migrate away from __pm_genpd_name_add_device()
  cpufreq: Use __func__ to print function's name
  cpufreq: staticize cpufreq_cpu_get_raw()
  PM / Domains: Ensure subdomain is not in use before removing
  cpufreq: Add ARM_MT8173_CPUFREQ dependency on THERMAL
  cpuidle/coupled: Add sanity check for safe_state_index
  PM / Domains: Try power off masters in error path of __pm_genpd_poweron()
  cpufreq: dt: Tolerance applies on both sides of target voltage
  cpufreq: dt: Print error on failing to mark OPPs as shared
  cpufreq: dt: Check OPP count before marking them shared
  kernel/cpu_pm: fix cpu_cluster_pm_exit comment

Merge branches 'pm-cpu', 'pm-cpuidle' and 'pm-domains'

2015-09-11T13:37:36+00:00

* pm-cpu:
  kernel/cpu_pm: fix cpu_cluster_pm_exit comment

* pm-cpuidle:
  cpuidle/coupled: Add sanity check for safe_state_index

* pm-domains:
  staging: board: Migrate away from __pm_genpd_name_add_device()
  PM / Domains: Ensure subdomain is not in use before removing
  PM / Domains: Try power off masters in error path of __pm_genpd_poweron()

Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

2015-09-03T23:27:01+00:00

Pull ARM development updates from Russell King:
 "Included in this update:

   - moving PSCI code from ARM64/ARM to drivers/

   - removal of some architecture internals from global kernel view

   - addition of software based "privileged no access" support using the
     old domains register to turn off the ability for kernel
     loads/stores to access userspace.  Only the proper accessors will
     be usable.

   - addition of early fixup support for early console

   - re-addition (and reimplementation) of OMAP special interconnect
     barrier

   - removal of finish_arch_switch()

   - only expose cpuX/online in sysfs if hotpluggable

   - a number of code cleanups"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (41 commits)
  ARM: software-based priviledged-no-access support
  ARM: entry: provide uaccess assembly macro hooks
  ARM: entry: get rid of multiple macro definitions
  ARM: 8421/1: smp: Collapse arch_cpu_idle_dead() into cpu_die()
  ARM: uaccess: provide uaccess_save_and_enable() and uaccess_restore()
  ARM: mm: improve do_ldrd_abort macro
  ARM: entry: ensure that IRQs are enabled when calling syscall_trace_exit()
  ARM: entry: efficiency cleanups
  ARM: entry: get rid of asm_trace_hardirqs_on_cond
  ARM: uaccess: simplify user access assembly
  ARM: domains: remove DOMAIN_TABLE
  ARM: domains: keep vectors in separate domain
  ARM: domains: get rid of manager mode for user domain
  ARM: domains: move initial domain setting value to asm/domains.h
  ARM: domains: provide domain_mask()
  ARM: domains: switch to keeping domain value in register
  ARM: 8419/1: dma-mapping: harmonize definition of DMA_ERROR_CODE
  ARM: 8417/1: refactor bitops functions with BIT_MASK() and BIT_WORD()
  ARM: 8416/1: Feroceon: use of_iomap() to map register base
  ARM: 8415/1: early fixmap support for earlycon
  ...

cpuidle/coupled: Add sanity check for safe_state_index

2015-09-03T01:05:47+00:00

Since we are using cpuidle_driver::safe_state_index directly as the
target state index, it is better to add the sanity check at the point
of registering the driver.

Signed-off-by: Xunlei Pang 
Signed-off-by: Rafael J. Wysocki