- Remaining changes from upstream ACPICA release 20140214 that introduce
code to automatically serialize the execution of methods creating any
named objects which really cannot be executed in parallel with each
other anyway (previously ACPICA attempted to address that by aborting
methods upon conflict detection, but that wasn't reliable enough and
led to other issues). From Bob Moore and Lv Zheng.
- intel_pstate fix to use del_timer_sync() instead of del_timer() in
the exit path before freeing the timer structure from Dirk Brandewie
(original patch from Thomas Gleixner).
- cpufreq fix related to system resume from Viresh Kumar.
- Serialization of frequency transitions in cpufreq that involve
PRECHANGE and POSTCHANGE notifications to avoid ordering issues
resulting from race conditions. From Srivatsa S Bhat and Viresh Kumar.
- Revert of an ACPI processor driver change that was based on a specific
interpretation of the ACPI spec which may not be correct (the relevant
part of the spec appears to be incomplete). From Hanjun Guo.
- Runtime PM core cleanups and documentation updates from Geert Uytterhoeven.
- PNP core cleanup from Michael Opdenacker.
/
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Merge tag 'pm+acpi-3.15-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more ACPI and power management updates from Rafael Wysocki:
"These are commits that were not quite ready when I sent the original
pull request for 3.15-rc1 several days ago, but they have spent some
time in linux-next since then and appear to be good to go. All of
them are fixes and cleanups.
Specifics:
- Remaining changes from upstream ACPICA release 20140214 that
introduce code to automatically serialize the execution of methods
creating any named objects which really cannot be executed in
parallel with each other anyway (previously ACPICA attempted to
address that by aborting methods upon conflict detection, but that
wasn't reliable enough and led to other issues). From Bob Moore
and Lv Zheng.
- intel_pstate fix to use del_timer_sync() instead of del_timer() in
the exit path before freeing the timer structure from Dirk
Brandewie (original patch from Thomas Gleixner).
- cpufreq fix related to system resume from Viresh Kumar.
- Serialization of frequency transitions in cpufreq that involve
PRECHANGE and POSTCHANGE notifications to avoid ordering issues
resulting from race conditions. From Srivatsa S Bhat and Viresh
Kumar.
- Revert of an ACPI processor driver change that was based on a
specific interpretation of the ACPI spec which may not be correct
(the relevant part of the spec appears to be incomplete). From
Hanjun Guo.
- Runtime PM core cleanups and documentation updates from Geert
Uytterhoeven.
- PNP core cleanup from Michael Opdenacker"
* tag 'pm+acpi-3.15-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: Make cpufreq_notify_transition & cpufreq_notify_post_transition static
cpufreq: Convert existing drivers to use cpufreq_freq_transition_{begin|end}
cpufreq: Make sure frequency transitions are serialized
intel_pstate: Use del_timer_sync in intel_pstate_cpu_stop
cpufreq: resume drivers before enabling governors
PM / Runtime: Spelling s/competing/completing/
PM / Runtime: s/foo_process_requests/foo_process_next_request/
PM / Runtime: GENERIC_SUBSYS_PM_OPS is gone
PM / Runtime: Correct documented return values for generic PM callbacks
PM / Runtime: Split line longer than 80 characters
PM / Runtime: dev_pm_info.runtime_error is signed
Revert "ACPI / processor: Make it possible to get APIC ID via GIC"
ACPICA: Enable auto-serialization as a default kernel behavior.
ACPICA: Ignore sync_level for methods that have been auto-serialized.
ACPICA: Add additional named objects for the auto-serialize method scan.
ACPICA: Add auto-serialization support for ill-behaved control methods.
ACPICA: Remove global option to serialize all control methods.
PNP: remove deprecated IRQF_DISABLED
- Device PM QoS support for latency tolerance constraints on systems with
hardware interfaces allowing such constraints to be specified. That is
necessary to prevent hardware-driven power management from becoming
overly aggressive on some systems and to prevent power management
features leading to excessive latencies from being used in some cases.
- Consolidation of the handling of ACPI hotplug notifications for device
objects. This causes all device hotplug notifications to go through
the root notify handler (that was executed for all of them anyway
before) that propagates them to individual subsystems, if necessary,
by executing callbacks provided by those subsystems (those callbacks
are associated with struct acpi_device objects during device
enumeration). As a result, the code in question becomes both smaller
in size and more straightforward and all of those changes should not
affect users.
- ACPICA update, including fixes related to the handling of _PRT in cases
when it is broken and the addition of "Windows 2013" to the list of
supported "features" for _OSI (which is necessary to support systems
that work incorrectly or don't even boot without it). Changes from
Bob Moore and Lv Zheng.
- Consolidation of ACPI _OST handling from Jiang Liu.
- ACPI battery and AC fixes allowing unusual system configurations to
be handled by that code from Alexander Mezin.
- New device IDs for the ACPI LPSS driver from Chiau Ee Chew.
- ACPI fan and thermal optimizations related to system suspend and resume
from Aaron Lu.
- Cleanups related to ACPI video from Jean Delvare.
- Assorted ACPI fixes and cleanups from Al Stone, Hanjun Guo, Lan Tianyu,
Paul Bolle, Tomasz Nowicki.
- Intel RAPL (Running Average Power Limits) driver cleanups from Jacob Pan.
- intel_pstate fixes and cleanups from Dirk Brandewie.
- cpufreq fixes related to system suspend/resume handling from Viresh Kumar.
- cpufreq core fixes and cleanups from Viresh Kumar, Stratos Karafotis,
Saravana Kannan, Rashika Kheria, Joe Perches.
- cpufreq drivers updates from Viresh Kumar, Zhuoyu Zhang, Rob Herring.
- cpuidle fixes related to the menu governor from Tuukka Tikkanen.
- cpuidle fix related to coupled CPUs handling from Paul Burton.
- Asynchronous execution of all device suspend and resume callbacks,
except for ->prepare and ->complete, during system suspend and resume
from Chuansheng Liu.
- Delayed resuming of runtime-suspended devices during system suspend for
the PCI bus type and ACPI PM domain.
- New set of PM helper routines to allow device runtime PM callbacks to
be used during system suspend and resume more easily from Ulf Hansson.
- Assorted fixes and cleanups in the PM core from Geert Uytterhoeven,
Prabhakar Lad, Philipp Zabel, Rashika Kheria, Sebastian Capella.
- devfreq fix from Saravana Kannan.
/
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Merge tag 'pm+acpi-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management updates from Rafael Wysocki:
"The majority of this material spent some time in linux-next, some of
it even several weeks. There are a few relatively fresh commits in
it, but they are mostly fixes and simple cleanups.
ACPI took the lead this time, both in terms of the number of commits
and the number of modified lines of code, cpufreq follows and there
are a few changes in the PM core and in cpuidle too.
A new feature that already got some LWN.net's attention is the device
PM QoS extension allowing latency tolerance requirements to be
propagated from leaf devices to their ancestors with hardware
interfaces for specifying latency tolerance. That should help systems
with hardware-driven power management to avoid going too far with it
in cases when there are latency tolerance constraints.
There also are some significant changes in the ACPI core related to
the way in which hotplug notifications are handled. They affect PCI
hotplug (ACPIPHP) and the ACPI dock station code too. The bottom line
is that all those notification now go through the root notify handler
and are propagated to the interested subsystems by means of callbacks
instead of having to install a notify handler for each device object
that we can potentially get hotplug notifications for.
In addition to that ACPICA will now advertise "Windows 2013"
compatibility for _OSI, because some systems out there don't work
correctly if that is not done (some of them don't even boot).
On the system suspend side of things, all of the device suspend and
resume callbacks, except for ->prepare() and ->complete(), are now
going to be executed asynchronously as that turns out to speed up
system suspend and resume on some platforms quite significantly and we
have a few more optimizations in that area.
Apart from that, there are some new device IDs and fixes and cleanups
all over. In particular, the system suspend and resume handling by
cpufreq should be improved and the cpuidle menu governor should be a
bit more robust now.
Specifics:
- Device PM QoS support for latency tolerance constraints on systems
with hardware interfaces allowing such constraints to be specified.
That is necessary to prevent hardware-driven power management from
becoming overly aggressive on some systems and to prevent power
management features leading to excessive latencies from being used
in some cases.
- Consolidation of the handling of ACPI hotplug notifications for
device objects. This causes all device hotplug notifications to go
through the root notify handler (that was executed for all of them
anyway before) that propagates them to individual subsystems, if
necessary, by executing callbacks provided by those subsystems
(those callbacks are associated with struct acpi_device objects
during device enumeration). As a result, the code in question
becomes both smaller in size and more straightforward and all of
those changes should not affect users.
- ACPICA update, including fixes related to the handling of _PRT in
cases when it is broken and the addition of "Windows 2013" to the
list of supported "features" for _OSI (which is necessary to
support systems that work incorrectly or don't even boot without
it). Changes from Bob Moore and Lv Zheng.
- Consolidation of ACPI _OST handling from Jiang Liu.
- ACPI battery and AC fixes allowing unusual system configurations to
be handled by that code from Alexander Mezin.
- New device IDs for the ACPI LPSS driver from Chiau Ee Chew.
- ACPI fan and thermal optimizations related to system suspend and
resume from Aaron Lu.
- Cleanups related to ACPI video from Jean Delvare.
- Assorted ACPI fixes and cleanups from Al Stone, Hanjun Guo, Lan
Tianyu, Paul Bolle, Tomasz Nowicki.
- Intel RAPL (Running Average Power Limits) driver cleanups from
Jacob Pan.
- intel_pstate fixes and cleanups from Dirk Brandewie.
- cpufreq fixes related to system suspend/resume handling from Viresh
Kumar.
- cpufreq core fixes and cleanups from Viresh Kumar, Stratos
Karafotis, Saravana Kannan, Rashika Kheria, Joe Perches.
- cpufreq drivers updates from Viresh Kumar, Zhuoyu Zhang, Rob
Herring.
- cpuidle fixes related to the menu governor from Tuukka Tikkanen.
- cpuidle fix related to coupled CPUs handling from Paul Burton.
- Asynchronous execution of all device suspend and resume callbacks,
except for ->prepare and ->complete, during system suspend and
resume from Chuansheng Liu.
- Delayed resuming of runtime-suspended devices during system suspend
for the PCI bus type and ACPI PM domain.
- New set of PM helper routines to allow device runtime PM callbacks
to be used during system suspend and resume more easily from Ulf
Hansson.
- Assorted fixes and cleanups in the PM core from Geert Uytterhoeven,
Prabhakar Lad, Philipp Zabel, Rashika Kheria, Sebastian Capella.
- devfreq fix from Saravana Kannan"
* tag 'pm+acpi-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits)
PM / devfreq: Rewrite devfreq_update_status() to fix multiple bugs
PM / sleep: Correct whitespace errors in <linux/pm.h>
intel_pstate: Set core to min P state during core offline
cpufreq: Add stop CPU callback to cpufreq_driver interface
cpufreq: Remove unnecessary braces
cpufreq: Fix checkpatch errors and warnings
cpufreq: powerpc: add cpufreq transition latency for FSL e500mc SoCs
MAINTAINERS: Reorder maintainer addresses for PM and ACPI
PM / Runtime: Update runtime_idle() documentation for return value meaning
video / output: Drop display output class support
fujitsu-laptop: Drop unneeded include
acer-wmi: Stop selecting VIDEO_OUTPUT_CONTROL
ACPI / gpu / drm: Stop selecting VIDEO_OUTPUT_CONTROL
ACPI / video: fix ACPI_VIDEO dependencies
cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE}
cpufreq: Do not allow ->setpolicy drivers to provide ->target
cpufreq: arm_big_little: set 'physical_cluster' for each CPU
cpufreq: arm_big_little: make vexpress driver depend on bL core driver
ACPI / button: Add ACPI Button event via netlink routine
ACPI: Remove duplicate definitions of PREFIX
...
Pull timer updates from Ingo Molnar:
"The main purpose is to fix a full dynticks bug related to
virtualization, where steal time accounting appears to be zero in
/proc/stat even after a few seconds of competing guests running busy
loops in a same host CPU. It's not a regression though as it was
there since the beginning.
The other commits are preparatory work to fix the bug and various
cleanups"
* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
arch: Remove stub cputime.h headers
sched: Remove needless round trip nsecs <-> tick conversion of steal time
cputime: Fix jiffies based cputime assumption on steal accounting
cputime: Bring cputime -> nsecs conversion
cputime: Default implementation of nsecs -> cputime conversion
cputime: Fix nsecs_to_cputime() return type cast
- PCI I/O space extended to 16M (in preparation of PCIe support patches)
- Dropping ZONE_DMA32 in favour of ZONE_DMA (we only need one for the
time being), together with swiotlb late initialisation to correctly
setup the bounce buffer
- DMA API cache maintenance support (not all ARMv8 platforms have
hardware cache coherency)
- Crypto extensions advertising via ELF_HWCAP2 for compat user space
- Perf support for dwarf unwinding in compat mode
- asm/tlb.h converted to the generic mmu_gather code
- asm-generic rwsem implementation
- Code clean-up
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull ARM64 updates from Catalin Marinas:
- KGDB support for arm64
- PCI I/O space extended to 16M (in preparation of PCIe support
patches)
- Dropping ZONE_DMA32 in favour of ZONE_DMA (we only need one for the
time being), together with swiotlb late initialisation to correctly
setup the bounce buffer
- DMA API cache maintenance support (not all ARMv8 platforms have
hardware cache coherency)
- Crypto extensions advertising via ELF_HWCAP2 for compat user space
- Perf support for dwarf unwinding in compat mode
- asm/tlb.h converted to the generic mmu_gather code
- asm-generic rwsem implementation
- Code clean-up
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (42 commits)
arm64: Remove pgprot_dmacoherent()
arm64: Support DMA_ATTR_WRITE_COMBINE
arm64: Implement custom mmap functions for dma mapping
arm64: Fix __range_ok macro
arm64: Fix duplicated Kconfig entries
arm64: mm: Route pmd thp functions through pte equivalents
arm64: rwsem: use asm-generic rwsem implementation
asm-generic: rwsem: de-PPCify rwsem.h
arm64: enable generic CPU feature modalias matching for this architecture
arm64: smp: make local symbol static
arm64: debug: make local symbols static
ARM64: perf: support dwarf unwinding in compat mode
ARM64: perf: add support for frame pointer unwinding in compat mode
ARM64: perf: add support for perf registers API
arm64: Add boot time configuration of Intermediate Physical Address size
arm64: Do not synchronise I and D caches for special ptes
arm64: Make DMA coherent and strongly ordered mappings not executable
arm64: barriers: add dmb barrier
arm64: topology: Implement basic CPU topology support
arm64: advertise ARMv8 extensions to 32-bit compat ELF binaries
...
cpufreq_notify_transition() and cpufreq_notify_post_transition() shouldn't be
called directly by cpufreq drivers anymore and so these should be marked static.
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CPUFreq core has new infrastructure that would guarantee serialized calls to
target() or target_index() callbacks. These are called
cpufreq_freq_transition_begin() and cpufreq_freq_transition_end().
This patch converts existing drivers to use these new set of routines.
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Whenever we change the frequency of a CPU, we call the PRECHANGE and POSTCHANGE
notifiers. They must be serialized, i.e. PRECHANGE and POSTCHANGE notifiers
should strictly alternate, thereby preventing two different sets of PRECHANGE or
POSTCHANGE notifiers from interleaving arbitrarily.
The following examples illustrate why this is important:
Scenario 1:
-----------
A thread reading the value of cpuinfo_cur_freq, will call
__cpufreq_cpu_get()->cpufreq_out_of_sync()->cpufreq_notify_transition()
The ondemand governor can decide to change the frequency of the CPU at the same
time and hence it can end up sending the notifications via ->target().
If the notifiers are not serialized, the following sequence can occur:
- PRECHANGE Notification for freq A (from cpuinfo_cur_freq)
- PRECHANGE Notification for freq B (from target())
- Freq changed by target() to B
- POSTCHANGE Notification for freq B
- POSTCHANGE Notification for freq A
We can see from the above that the last POSTCHANGE Notification happens for freq
A but the hardware is set to run at freq B.
Where would we break then?: adjust_jiffies() in cpufreq.c & cpufreq_callback()
in arch/arm/kernel/smp.c (which also adjusts the jiffies). All the
loops_per_jiffy calculations will get messed up.
Scenario 2:
-----------
The governor calls __cpufreq_driver_target() to change the frequency. At the
same time, if we change scaling_{min|max}_freq from sysfs, it will end up
calling the governor's CPUFREQ_GOV_LIMITS notification, which will also call
__cpufreq_driver_target(). And hence we end up issuing concurrent calls to
->target().
Typically, platforms have the following logic in their ->target() routines:
(Eg: cpufreq-cpu0, omap, exynos, etc)
A. If new freq is more than old: Increase voltage
B. Change freq
C. If new freq is less than old: decrease voltage
Now, if the two concurrent calls to ->target() are X and Y, where X is trying to
increase the freq and Y is trying to decrease it, we get the following race
condition:
X.A: voltage gets increased for larger freq
Y.A: nothing happens
Y.B: freq gets decreased
Y.C: voltage gets decreased
X.B: freq gets increased
X.C: nothing happens
Thus we can end up setting a freq which is not supported by the voltage we have
set. That will probably make the clock to the CPU unstable and the system might
not work properly anymore.
This patch introduces a set of synchronization primitives to serialize frequency
transitions, which are to be used as shown below:
cpufreq_freq_transition_begin();
//Perform the frequency change
cpufreq_freq_transition_end();
The _begin() call sends the PRECHANGE notification whereas the _end() call sends
the POSTCHANGE notification. Also, all the necessary synchronization is handled
within these calls. In particular, even drivers which set the ASYNC_NOTIFICATION
flag can also use these APIs for performing frequency transitions (ie., you can
call _begin() from one task, and call the corresponding _end() from a different
task).
The actual synchronization underneath is not that complicated:
The key challenge is to allow drivers to begin the transition from one thread
and end it in a completely different thread (this is to enable drivers that do
asynchronous POSTCHANGE notification from bottom-halves, to also use the same
interface).
To achieve this, a 'transition_ongoing' flag, a 'transition_lock' spinlock and a
wait-queue are added per-policy. The flag and the wait-queue are used in
conjunction to create an "uninterrupted flow" from _begin() to _end(). The
spinlock is used to ensure that only one such "flow" is in flight at any given
time. Put together, this provides us all the necessary synchronization.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Ensure that no timer callback is running since we are about to free
the timer structure. We cannot guarantee that the call back is called
on the CPU where the timer is running.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
During suspend, we first stop governors and then suspend cpufreq drivers and
resume must be exactly opposite of that. i.e. resume drivers first and then
start governors.
But the current code in resume enables governors first and then resume drivers.
Fix it be changing code sequence there.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Change to use the new ->stop_cpu() callback to do clean up during CPU
hotplug. The requested P state for an offline core will be used by the
hardware coordination function to select the package P state. If the
core is under load when it is offlined it will fix the package P state
floor to the requested P state of offline core.
Reported-by: Patrick Marlier <patrick.marlier@gmail.com>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This callback allows the driver to do clean up before the CPU is
completely down and its state cannot be modified. This is used
by the intel_pstate driver to reduce the requested P state prior to
the core going away. This is required because the requested P state
of the offline core is used to select the package P state. This
effectively sets the floor package P state to the requested P state on
the offline core.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
[rjw: Minor modifications]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove unnecessary braces from a single statement.
Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix 2 checkpatch errors about using assignment in if condition,
1 checkpatch error about a required space after comma
and 3 warnings about line over 80 characters.
Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
According to the data provided by HW Team, at least 12 internal platform
clock cycles are required to stabilize a DFS clock switch on FSL e500mc Socs.
This patch replaces the CPUFREQ_ETERNAL with appropriate HW clock transition
latency to make DFS governors work normally on Freescale e500mc boards.
Signed-off-by: Zhuoyu Zhang <Zhuoyu.Zhang@freescale.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Two cpufreq notifiers CPUFREQ_RESUMECHANGE and CPUFREQ_SUSPENDCHANGE have
not been used for some time, so remove them to clean up code a bit.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq drivers that provide the ->setpolicy() callback are supposed
to have integrated governors, so they don't need to set ->target()
or ->target_index() and may confuse the core if any of these callbacks
is present.
For this reason, add a check preventing ->setpolicy cpufreq drivers
from registering if they have non-NULL ->target or ->target_index.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
We have a per-CPU variable for managing which cluster a CPU belongs to.
Currently, physical_cluster is set for policy->cpu only which leads to
the following on some SoC's:
- There are two clusters:
- Cluster 0 has four ARM Cortex A7 CPUs (slower ones): 0,1,2,3
- Cluster 1 has four ARM Cortex A15 CPUs (faster ones): 4,5,6,7
- CPUs are booted in order 0,1..7 and so initially policy->cpu for A7 cluster
would be 0 and for A15 cluster would be 4.
- Now CPU4 (i.e. A15_0) is hotplugged out and so policy->cpu for A15 cluster
becomes 5 (i.e. A15_1).
- But physical cluster is only set for CPU0 and CPU4 in ARM big LITTLE driver
and isn't updated.
- Now freq change request comes for A15 cluster and we would try to update freq
of physical_cluster of CPU5, i.e. A15_1. And it is currently set to zero
(default value of uninitialized global variables).
- And so we actually try to change freq of A7 cluster instead of A15.
- This also results in kernel crash as sometimes we might request freq above
A7's limit and CPU may behave badly..
Fix this by initializing physical_cluster for all CPUs of a policy.
Based on previous work by Xin Wang.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently vexpress big LITTLE driver selects ARM_BIG_LITTLE_CPUFREQ, so
if CONFIG_BIG_LITTLE isn't enabled and CONFIG_ARM_VEXPRESS_SPC_CPUFREQ
is enabled, we get the following build warnings:
warning: (ARM_VEXPRESS_SPC_CPUFREQ) selects ARM_BIG_LITTLE_CPUFREQ which has
unmet direct dependencies (ARCH_HAS_CPUFREQ && CPU_FREQ && (ARM || ARM64) && ARM
&& BIG_LITTLE && ARM_CPU_TOPOLOGY && HAVE_CLK)
To fix this, make ARM_VEXPRESS_SPC_CPUFREQ depend on ARM_BIG_LITTLE_CPUFREQ
instead of selecting it.
This also moves the entry for ARM_VEXPRESS_SPC_CPUFREQ along with other
big LITTLE config entries.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The architectures that override cputime_t (s390, ppc) don't provide
any version of nsecs_to_cputime(). Indeed this cputime_t implementation
by backend only happens when CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y under
which the core code doesn't make any use of nsecs_to_cputime().
At least for now.
We are going to make a broader use of it so lets provide a default
version with a per usecs granularity. It should be good enough for most
usecases.
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
After commit da60ce9f2f (cpufreq: call cpufreq_driver->get() after
calling ->init()) __cpufreq_add_dev() sometimes fails for CPUs handled
by intel_pstate, because that driver may return 0 from its ->get()
callback if it has not run long enough to collect enough samples on the
given CPU. That didn't happen before commit da60ce9f2f which added
policy->cur initialization to __cpufreq_add_dev() to help reduce code
duplication in other cpufreq drivers.
However, the code added by commit da60ce9f2f need not be executed
for cpufreq drivers having the ->setpolicy callback defined, because
the subsequent invocation of cpufreq_set_policy() will use that
callback to initialize the policy anyway and it doesn't need
policy->cur to be initialized upfront. The analogous code in
cpufreq_update_policy() is also unnecessary for cpufreq drivers
having ->setpolicy set and may be skipped for them as well.
Since intel_pstate provides ->setpolicy, skipping the upfront
policy->cur initialization for cpufreq drivers with that callback
set will cover intel_pstate and the problem it's been having after
commit da60ce9f2f will be addressed.
Fixes: da60ce9f2f (cpufreq: call cpufreq_driver->get() after calling ->init())
References: https://bugzilla.kernel.org/show_bug.cgi?id=71931
Reported-and-tested-by: Patrik Lundquist <patrik.lundquist@gmail.com>
Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Cc: 3.13+ <stable@vger.kernel.org> # 3.13+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
As multiplatform build is being adopted by more and more
ARM platforms, initcall function should be used very carefully.
For example, when SPEAr cpufreq driver is enabled on a kernel
booted on a non-SPEAr board, we will get following boot time error:
spear_cpufreq: Invalid cpufreq_tbl
To eliminate this undesired the effect, the patch changes SPEAr
driver to have it instantiated as a platform_driver. Then it will
only run on platforms that create the platform_device "spear-cpufreq".
This patch also creates platform node for SPEAr13xx boards.
Reported-by: Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We have used 'frozen' variable/function parameter at many places to
distinguish between CPU offline/online on suspend/resume vs sysfs
removals. We now have another variable cpufreq_suspended which can
be used in these cases, so we can get rid of all those variables or
function parameters.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_generic_exit() is empty now and can be deleted.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
freq table is not per CPU but per policy, so it makes more sense to
keep it within struct cpufreq_policy instead of a per-cpu variable.
This patch does it. Over that, there is no need to set policy->freq_table
to NULL in ->exit(), as policy structure is going to be freed soon.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq core now supports suspending and resuming of cpufreq
drivers and governors during systems suspend and resume, so use
the common infrastructure instead of defining special PM notifiers
for the same thing.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq core now supports suspending and resuming of cpufreq
drivers and governors during systems suspend and resume, so use
the common infrastructure instead of defining special PM notifiers
for the same thing.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq core now supports suspending and resuming of cpufreq
drivers and governors during systems suspend and resume, so use
the common infrastructure instead of defining special PM notifiers
for the same thing.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Multiple platforms need to set CPUs to a particular frequency before
suspending the system, so provide a common infrastructure for them.
Those platforms only need to point their ->suspend callback pointers
to the generic routine.
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch adds cpufreq suspend/resume calls to dpm_{suspend|resume}()
for handling suspend/resume of cpufreq governors.
Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found an issue where the
tunables configuration for clusters/sockets with non-boot CPUs was
lost after system suspend/resume, as we were notifying governors with
CPUFREQ_GOV_POLICY_EXIT on removal of the last CPU for that policy
which caused the tunables memory to be freed.
This is fixed by preventing any governor operations from being
carried out between the device suspend and device resume stages of
system suspend and resume, respectively.
We could have added these callbacks at dpm_{suspend|resume}_noirq()
level, but there is an additional problem that the majority of I/O
devices is already suspended at that point and if cpufreq drivers
want to change the frequency before suspending, then that not be
possible on some platforms (which depend on peripherals like i2c,
regulators, etc).
Reported-and-tested-by: Lan Tianyu <tianyu.lan@intel.com>
Reported-by: Jinhyuk Choi <jinchoi@broadcom.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We call __find_governor() during the addition of the first CPU of
each policy from __cpufreq_add_dev() to find the last governor used
for this CPU before it was hot-removed.
After that we call cpufreq_parse_governor() in cpufreq_init_policy(),
either with this governor, or with the default governor. Right after
that policy->governor is set to NULL.
While that code is not functionally problematic, the structure of it
is suboptimal, because some of the code required in cpufreq_init_policy()
is being executed by its caller, __cpufreq_add_dev(). So, it would make
more sense to get all of it together in a single place to make code more
readable.
Accordingly, move the code needed for policy initialization to
cpufreq_init_policy() and initialize policy->governor to NULL at the
beginning.
In order to clean up the code a bit more, some of the #ifdefs for
CONFIG_HOTPLUG_CPU are dropped too.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
policy->rwsem is used to lock access to all parts of code modifying
struct cpufreq_policy, but it's not used on a new policy created by
__cpufreq_add_dev().
Because of that, if cpufreq_update_policy() is called in a tight loop
on one CPU in parallel with offline/online of another CPU, then the
following crash can be triggered:
Unable to handle kernel NULL pointer dereference at virtual address 00000020
pgd = c0003000
[00000020] *pgd=80000000004003, *pmd=00000000
Internal error: Oops: 206 [#1] PREEMPT SMP ARM
PC is at __cpufreq_governor+0x10/0x1ac
LR is at cpufreq_update_policy+0x114/0x150
---[ end trace f23a8defea6cd706 ]---
Kernel panic - not syncing: Fatal exception
CPU0: stopping
CPU: 0 PID: 7136 Comm: mpdecision Tainted: G D W 3.10.0-gd727407-00074-g979ede8 #396
[<c0afe180>] (notifier_call_chain+0x40/0x68) from [<c02a23ac>] (__blocking_notifier_call_chain+0x40/0x58)
[<c02a23ac>] (__blocking_notifier_call_chain+0x40/0x58) from [<c02a23d8>] (blocking_notifier_call_chain+0x14/0x1c)
[<c02a23d8>] (blocking_notifier_call_chain+0x14/0x1c) from [<c0803c68>] (cpufreq_set_policy+0xd4/0x2b8)
[<c0803c68>] (cpufreq_set_policy+0xd4/0x2b8) from [<c0803e7c>] (cpufreq_init_policy+0x30/0x98)
[<c0803e7c>] (cpufreq_init_policy+0x30/0x98) from [<c0805a18>] (__cpufreq_add_dev.isra.17+0x4dc/0x7a4)
[<c0805a18>] (__cpufreq_add_dev.isra.17+0x4dc/0x7a4) from [<c0805d38>] (cpufreq_cpu_callback+0x58/0x84)
[<c0805d38>] (cpufreq_cpu_callback+0x58/0x84) from [<c0afe180>] (notifier_call_chain+0x40/0x68)
[<c0afe180>] (notifier_call_chain+0x40/0x68) from [<c02812dc>] (__cpu_notify+0x28/0x44)
[<c02812dc>] (__cpu_notify+0x28/0x44) from [<c0aeed90>] (_cpu_up+0xf4/0x1dc)
[<c0aeed90>] (_cpu_up+0xf4/0x1dc) from [<c0aeeed4>] (cpu_up+0x5c/0x78)
[<c0aeeed4>] (cpu_up+0x5c/0x78) from [<c0aec808>] (store_online+0x44/0x74)
[<c0aec808>] (store_online+0x44/0x74) from [<c03a40f4>] (sysfs_write_file+0x108/0x14c)
[<c03a40f4>] (sysfs_write_file+0x108/0x14c) from [<c03517d4>] (vfs_write+0xd0/0x180)
[<c03517d4>] (vfs_write+0xd0/0x180) from [<c0351ca8>] (SyS_write+0x38/0x68)
[<c0351ca8>] (SyS_write+0x38/0x68) from [<c0205de0>] (ret_fast_syscall+0x0/0x30)
Fix that by taking locks at appropriate places in __cpufreq_add_dev()
as well.
Reported-by: Saravana Kannan <skannan@codeaurora.org>
Suggested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Policy must be fully initialized before it is being made available
for use by others. Otherwise cpufreq_cpu_get() would be able to grab
a half initialized policy structure that might not have affected_cpus
(for example) populated. Then, anybody accessing those fields will get
a wrong value and that will lead to unpredictable results.
In order to fix this, do all the necessary initialization before we
make the policy structure available via cpufreq_cpu_get(). That will
guarantee that any code accessing fields of the policy will get
correct data from them.
Reported-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If a module calls cpufreq_get while cpufreq is initializing, it's
possible for it to be called after cpufreq_driver is set but before
cpufreq_cpu_data is written during subsys_interface_register. This
happens because cpufreq_get doesn't take the cpufreq_driver_lock
around its use of cpufreq_cpu_data.
Fix this by using cpufreq_cpu_get(cpu) to look up the policy rather
than reading it out of cpufreq_cpu_data directly. cpufreq_cpu_get()
takes the appropriate locks to prevent this race from happening.
Since it's possible for policy to be NULL if the caller passes in an
invalid CPU number or calls the function before cpufreq is initialized,
delete the BUG_ON(!policy) and simply return 0. Don't try to return
-ENOENT because that's negative and the function returns an unsigned
integer.
References: https://bbs.archlinux.org/viewtopic.php?id=177934
Signed-off-by: Aaron Plattner <aplattner@nvidia.com>
Cc: 3.13+ <stable@vger.kernel.org> # 3.13+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_frequency_get_table() is called from all callers of
__cpufreq_stats_create_table(). So, move it inside.
Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove sysfs group if __cpufreq_stats_create_table() fails after creating
one.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
__cpufreq_stats_create_table always gets pass the valid and real policy
struct. So, there's no need to call cpufreq_cpu_get() to get the policy
again.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
commit d253d2a526 (Improve accuracy by not truncating until final
result), changed internal variables of the PID to be fixed point
numbers. Update the pid_reset() to reflect this change.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Remove unneeded sample buffers, intel_pstate operates on the most
recent sample only. This save some memory and make the code more
readable.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_update_policy() calls cpufreq_driver->get() to get current
frequency of a CPU and it is not supposed to fail or return zero.
Return error in case that happens.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Enable cpufreq and power kconfig menus on arm64 along with arm cpufreq
drivers. The power menu is needed for OPP support. At least on Calxeda
systems, the same cpufreq driver is used for arm and arm64 based
systems.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Enable cpufreq and power kconfig menus on arm64 along with arm cpufreq
drivers. The power menu is needed for OPP support. At least on Calxeda
systems, the same cpufreq driver is used for arm and arm64 based
systems.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Mark function as static in cpufreq.c because it is not
used outside this file.
This eliminates the following warning in cpufreq.c:
drivers/cpufreq/cpufreq.c:355:9: warning: no previous prototype for ‘show_boost’ [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit fcb6a15c2e (intel_pstate: Take core C0 time into account for
core busy calculation) introduced a regression on some processor SKUs
supported by intel_pstate. This was due to the truncation caused by
using integer math to calculate core busy and C0 percentages.
On a i7-4770K processor operating at 800Mhz going to 100% utilization
the percent busy of the CPU using integer math is 22%, but it actually
is 22.85%. This value scaled to the current frequency returned 97
which the PID interpreted as no error and did not adjust the P state.
Tested on i7-4770K, i7-2600, i5-3230M.
Fixes: fcb6a15c2e (intel_pstate: Take core C0 time into account for core busy calculation)
References: https://lkml.org/lkml/2014/2/19/626
References: https://bugzilla.kernel.org/show_bug.cgi?id=70941
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq_update_policy() is called from two places currently. From a
workqueue handled queued from cpufreq_bp_resume() for boot CPU and
from cpufreq_cpu_callback() whenever a CPU is added.
The first one makes sure that boot CPU is running on the frequency
present in policy->cpu. But we don't really need a call from
cpufreq_cpu_callback(), because we always call cpufreq_driver->init()
(which will set policy->cur correctly) whenever first CPU of any
policy is added back. And so every policy structure is guaranteed to
have the right frequency in policy->cur.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reduce the rampant usage of goto and the indentation level in
cpufreq_set_policy() to improve the readability of that code.
No functional changes should result from that.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
A documentation update exposed the existance of the turbo ratio
register. Update baytrail support to use the turbo range.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Cc: 3.13+ <stable@vger.kernel.org> # 3.13+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Linus Torvalds