- Fix the PM core to avoid introducing a runtime PM usage counter
imbalance when adding device links during driver probe (Rafael
Wysocki).
- Fix the operating performance points (OPP) framework to ensure
that the regulator voltage is always updated as appropriate when
updating clock rates (Waldemar Rymarkiewicz).
- Fix the intel_pstate driver to use correct max/min limits for
cores with differing maximum frequences (Srinivas Pandruvada).
- Fix a typo in the intel_pstate driver documentation (Rafael
Wysocki).
- Fix two issues with the recently added Kryo cpufreq driver (Ilia
Lin).
- Fix two recent regressions and some other minor issues in the
turbostat utility and extend it to provide some more diagnostic
information (Len Brown, Nathan Ciobanu).
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Merge tag 'pm-4.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These are mostly fixes, including some fixes for changes made during
the recent merge window and some "stable" material, plus some minor
extensions of the turbostat utility.
Specifics:
- Fix the PM core to avoid introducing a runtime PM usage counter
imbalance when adding device links during driver probe (Rafael
Wysocki).
- Fix the operating performance points (OPP) framework to ensure that
the regulator voltage is always updated as appropriate when
updating clock rates (Waldemar Rymarkiewicz).
- Fix the intel_pstate driver to use correct max/min limits for cores
with differing maximum frequences (Srinivas Pandruvada).
- Fix a typo in the intel_pstate driver documentation (Rafael
Wysocki).
- Fix two issues with the recently added Kryo cpufreq driver (Ilia
Lin).
- Fix two recent regressions and some other minor issues in the
turbostat utility and extend it to provide some more diagnostic
information (Len Brown, Nathan Ciobanu)"
* tag 'pm-4.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Documentation: intel_pstate: Fix typo
tools/power turbostat: version 18.06.20
tools/power turbostat: add the missing command line switches
tools/power turbostat: add single character tokens to help
tools/power turbostat: alphabetize the help output
tools/power turbostat: fix segfault on 'no node' machines
tools/power turbostat: add optional APIC X2APIC columns
tools/power turbostat: decode cpuid.1.HT
tools/power turbostat: fix show/hide issues resulting from mis-merge
PM / OPP: Update voltage in case freq == old_freq
cpufreq: intel_pstate: Fix scaling max/min limits with Turbo 3.0
cpufreq: kryo: Add module remove and exit
cpufreq: kryo: Fix possible error code dereference
PM / core: Fix supplier device runtime PM usage counter imbalance
If a device link is added via device_link_add() by the driver of the
link's consumer device, the supplier's runtime PM usage counter is
going to be dropped by the pm_runtime_put_suppliers() call in
driver_probe_device(). However, in that case it is not incremented
unless the supplier driver is already present and the link is not
stateless. That leads to a runtime PM usage counter imbalance for
the supplier device in a few cases.
To prevent that from happening, bump up the supplier runtime
PM usage counter in device_link_add() for all links with the
DL_FLAG_PM_RUNTIME flag set that are added at the consumer probe
time. Use pm_runtime_get_noresume() for that as the callers of
device_link_add() who want the supplier to be resumed by it are
expected to pass DL_FLAG_RPM_ACTIVE in flags to it anyway, but
additionally resume the supplier if the link is added during
consumer driver probe to retain the existing behavior for the
callers depending on it.
Fixes: 21d5c57b37 (PM / runtime: Use device links)
Reported-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: 4.10+ <stable@vger.kernel.org> # 4.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently the code is split over various files with dma- prefixes in the
lib/ and drives/base directories, and the number of files keeps growing.
Move them into a single directory to keep the code together and remove
the file name prefixes. To match the irq infrastructure this directory
is placed under the kernel/ directory.
Signed-off-by: Christoph Hellwig <hch@lst.de>
- Revert a recent PM core change that attempted to fix an issue
related to device links, but introduced a regression (Rafael
Wysocki).
- Fix build when the recently added cpufreq driver for Kryo
processors is selected by making it possible to build that
driver as a module (Arnd Bergmann).
- Fix the long idle detection mechanism in the out-of-band
(ondemand and conservative) cpufreq governors (Chen Yu).
- Add support for devices in multiple power domains to the
generic power domains (genpd) framework (Ulf Hansson).
- Add support for iowait boosting on systems with hardware-managed
P-states (HWP) enabled to the intel_pstate driver and make it use
that feature on systems with Skylake Xeon processors as it is
reported to improve performance significantly on those systems
(Srinivas Pandruvada).
- Fix and update the acpi_cpufreq, ti-cpufreq and imx6q cpufreq
drivers (Colin Ian King, Suman Anna, Sébastien Szymanski).
- Change the behavior of the wakeup_count device attribute in
sysfs to expose the number of events when the device might have
aborted system suspend in progress (Ravi Chandra Sadineni).
- Fix two minor issues in the cpupower utility (Abhishek Goel,
Colin Ian King).
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Merge tag 'pm-4.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki:
"These revert a recent PM core change that introduced a regression, fix
the build when the recently added Kryo cpufreq driver is selected, add
support for devices attached to multiple power domains to the generic
power domains (genpd) framework, add support for iowait boosting on
systens with hardware-managed P-states (HWP) enabled to the
intel_pstate driver, modify the behavior of the wakeup_count device
attribute in sysfs, fix a few issues and clean up some ugliness,
mostly in cpufreq (core and drivers) and in the cpupower utility.
Specifics:
- Revert a recent PM core change that attempted to fix an issue
related to device links, but introduced a regression (Rafael
Wysocki)
- Fix build when the recently added cpufreq driver for Kryo
processors is selected by making it possible to build that driver
as a module (Arnd Bergmann)
- Fix the long idle detection mechanism in the out-of-band (ondemand
and conservative) cpufreq governors (Chen Yu)
- Add support for devices in multiple power domains to the generic
power domains (genpd) framework (Ulf Hansson)
- Add support for iowait boosting on systems with hardware-managed
P-states (HWP) enabled to the intel_pstate driver and make it use
that feature on systems with Skylake Xeon processors as it is
reported to improve performance significantly on those systems
(Srinivas Pandruvada)
- Fix and update the acpi_cpufreq, ti-cpufreq and imx6q cpufreq
drivers (Colin Ian King, Suman Anna, Sébastien Szymanski)
- Change the behavior of the wakeup_count device attribute in sysfs
to expose the number of events when the device might have aborted
system suspend in progress (Ravi Chandra Sadineni)
- Fix two minor issues in the cpupower utility (Abhishek Goel, Colin
Ian King)"
* tag 'pm-4.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Revert "PM / runtime: Fixup reference counting of device link suppliers at probe"
cpufreq: imx6q: check speed grades for i.MX6ULL
cpufreq: governors: Fix long idle detection logic in load calculation
cpufreq: intel_pstate: enable boost for Skylake Xeon
PM / wakeup: Export wakeup_count instead of event_count via sysfs
PM / Domains: Add dev_pm_domain_attach_by_id() to manage multi PM domains
PM / Domains: Add support for multi PM domains per device to genpd
PM / Domains: Split genpd_dev_pm_attach()
PM / Domains: Don't attach devices in genpd with multi PM domains
PM / Domains: dt: Allow power-domain property to be a list of specifiers
cpufreq: intel_pstate: New sysfs entry to control HWP boost
cpufreq: intel_pstate: HWP boost performance on IO wakeup
cpufreq: intel_pstate: Add HWP boost utility and sched util hooks
cpufreq: ti-cpufreq: Use devres managed API in probe()
cpufreq: ti-cpufreq: Fix an incorrect error return value
cpufreq: ACPI: make function acpi_cpufreq_fast_switch() static
cpufreq: kryo: allow building as a loadable module
cpupower : Fix header name to read idle state name
cpupower: fix spelling mistake: "logilename" -> "logfilename"
Additional updates of the generic power domains (genpd) framework
(support for devices attached to multiple domains) and the cpupower
utility (minor fixes) for 4.18-rc1.
* pm-domains:
PM / Domains: Add dev_pm_domain_attach_by_id() to manage multi PM domains
PM / Domains: Add support for multi PM domains per device to genpd
PM / Domains: Split genpd_dev_pm_attach()
PM / Domains: Don't attach devices in genpd with multi PM domains
PM / Domains: dt: Allow power-domain property to be a list of specifiers
* pm-tools:
cpupower : Fix header name to read idle state name
cpupower: fix spelling mistake: "logilename" -> "logfilename"
Revert commit 1e83786198 (PM / runtime: Fixup reference counting of
device link suppliers at probe), as it has introduced a regression
and the condition it was designed to address should be covered by the
existing code.
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Spectre v4 mitigation (Speculative Store Bypass Disable) support for
arm64 using SMC firmware call to set a hardware chicken bit
- ACPI PPTT (Processor Properties Topology Table) parsing support and
enable the feature for arm64
- Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The
primary motivation is Scalable Vector Extensions which requires more
space on the signal frame than the currently defined MINSIGSTKSZ
- ARM perf patches: allow building arm-cci as module, demote dev_warn()
to dev_dbg() in arm-ccn event_init(), miscellaneous cleanups
- cmpwait() WFE optimisation to avoid some spurious wakeups
- L1_CACHE_BYTES reverted back to 64 (for performance reasons that have
to do with some network allocations) while keeping ARCH_DMA_MINALIGN
to 128. cache_line_size() returns the actual hardware Cache Writeback
Granule
- Turn LSE atomics on by default in Kconfig
- Kernel fault reporting tidying
- Some #include and miscellaneous cleanups
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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:
"Apart from the core arm64 and perf changes, the Spectre v4 mitigation
touches the arm KVM code and the ACPI PPTT support touches drivers/
(acpi and cacheinfo). I should have the maintainers' acks in place.
Summary:
- Spectre v4 mitigation (Speculative Store Bypass Disable) support
for arm64 using SMC firmware call to set a hardware chicken bit
- ACPI PPTT (Processor Properties Topology Table) parsing support and
enable the feature for arm64
- Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The
primary motivation is Scalable Vector Extensions which requires
more space on the signal frame than the currently defined
MINSIGSTKSZ
- ARM perf patches: allow building arm-cci as module, demote
dev_warn() to dev_dbg() in arm-ccn event_init(), miscellaneous
cleanups
- cmpwait() WFE optimisation to avoid some spurious wakeups
- L1_CACHE_BYTES reverted back to 64 (for performance reasons that
have to do with some network allocations) while keeping
ARCH_DMA_MINALIGN to 128. cache_line_size() returns the actual
hardware Cache Writeback Granule
- Turn LSE atomics on by default in Kconfig
- Kernel fault reporting tidying
- Some #include and miscellaneous cleanups"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (53 commits)
arm64: Fix syscall restarting around signal suppressed by tracer
arm64: topology: Avoid checking numa mask for scheduler MC selection
ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled
arm64: cpu_errata: include required headers
arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file
arm64: signal: Report signal frame size to userspace via auxv
arm64/sve: Thin out initialisation sanity-checks for sve_max_vl
arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID
arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests
arm64: KVM: Add ARCH_WORKAROUND_2 support for guests
arm64: KVM: Add HYP per-cpu accessors
arm64: ssbd: Add prctl interface for per-thread mitigation
arm64: ssbd: Introduce thread flag to control userspace mitigation
arm64: ssbd: Restore mitigation status on CPU resume
arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation
arm64: ssbd: Add global mitigation state accessor
arm64: Add 'ssbd' command-line option
arm64: Add ARCH_WORKAROUND_2 probing
arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2
arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1
...
- Use overflow helpers in 2-factor allocators (Kees, Rasmus)
- Introduce overflow test module (Rasmus, Kees)
- Introduce saturating size helper functions (Matthew, Kees)
- Treewide use of struct_size() for allocators (Kees)
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Merge tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull overflow updates from Kees Cook:
"This adds the new overflow checking helpers and adds them to the
2-factor argument allocators. And this adds the saturating size
helpers and does a treewide replacement for the struct_size() usage.
Additionally this adds the overflow testing modules to make sure
everything works.
I'm still working on the treewide replacements for allocators with
"simple" multiplied arguments:
*alloc(a * b, ...) -> *alloc_array(a, b, ...)
and
*zalloc(a * b, ...) -> *calloc(a, b, ...)
as well as the more complex cases, but that's separable from this
portion of the series. I expect to have the rest sent before -rc1
closes; there are a lot of messy cases to clean up.
Summary:
- Introduce arithmetic overflow test helper functions (Rasmus)
- Use overflow helpers in 2-factor allocators (Kees, Rasmus)
- Introduce overflow test module (Rasmus, Kees)
- Introduce saturating size helper functions (Matthew, Kees)
- Treewide use of struct_size() for allocators (Kees)"
* tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
treewide: Use struct_size() for devm_kmalloc() and friends
treewide: Use struct_size() for vmalloc()-family
treewide: Use struct_size() for kmalloc()-family
device: Use overflow helpers for devm_kmalloc()
mm: Use overflow helpers in kvmalloc()
mm: Use overflow helpers in kmalloc_array*()
test_overflow: Add memory allocation overflow tests
overflow.h: Add allocation size calculation helpers
test_overflow: Report test failures
test_overflow: macrofy some more, do more tests for free
lib: add runtime test of check_*_overflow functions
compiler.h: enable builtin overflow checkers and add fallback code
Currently we export event_count instead of wakeup_count via the
per-device wakeup_count sysfs attribute. Change it to wakeup_count
to make it more meaningful.
wakeup_count increments only when events_check_enabled is set,
that is whenever writes the current wakeup count to
/sys/power/wakeup_count. Also events_check_enabled is cleared on
every resume. User space is expected to write to this just before
suspend. This way pm_wakeup_event(), when called from IRQs handles,
will increment wakeup_count only if we are in system-wide
suspend-resume cycle and should give a fair approximation of how many
times a device may have triggered a wakeup from system suspend.
event_count on the other hand will increment every time
pm_wakeup_event() is called irrespective of whether we are in a
suspend-resume cycle and some drivers call it on every interrupt
which makes it less useful for system wakeup tracking.
Signed-off-by: Ravi Chandra Sadineni <ravisadineni@chromium.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The existing dev_pm_domain_attach() function, allows a single PM domain to
be attached per device. To be able to support devices that are partitioned
across multiple PM domains, let's introduce a new interface,
dev_pm_domain_attach_by_id().
The dev_pm_domain_attach_by_id() returns a new allocated struct device with
the corresponding attached PM domain. This enables for example a driver to
operate on the new device from a power management point of view. The driver
may then also benefit from using the received device, to set up so called
device-links towards its original device. Depending on the situation, these
links may then be dynamically changed.
The new interface is typically called by drivers during their probe phase,
in case they manages devices which uses multiple PM domains. If that is the
case, the driver also becomes responsible of managing the detaching of the
PM domains, which typically should be done at the remove phase. Detaching
is done by calling the existing dev_pm_domain_detach() function and for
each of the received devices from dev_pm_domain_attach_by_id().
Note, currently its only genpd that supports multiple PM domains per
device, but dev_pm_domain_attach_by_id() can easily by extended to cover
other PM domain types, if/when needed.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
To support devices being partitioned across multiple PM domains, let's
begin with extending genpd to cope with these kind of configurations.
Therefore, add a new exported function genpd_dev_pm_attach_by_id(), which
is similar to the existing genpd_dev_pm_attach(), but with the difference
that it allows its callers to provide an index to the PM domain that it
wants to attach.
Note that, genpd_dev_pm_attach_by_id() shall only be called by the driver
core / PM core, similar to how the existing dev_pm_domain_attach() makes
use of genpd_dev_pm_attach(). However, this is implemented by following
changes on top.
Because, only one PM domain can be attached per device, genpd needs to
create a virtual device that it can attach/detach instead. More precisely,
let the new function genpd_dev_pm_attach_by_id() register a virtual struct
device via calling device_register(). Then let it attach this device to the
corresponding PM domain, rather than the one that is provided by the
caller. The actual attaching is done via re-using the existing genpd OF
functions.
At successful attachment, genpd_dev_pm_attach_by_id() returns the created
virtual device, which allows the caller to operate on it to deal with power
management. Following changes on top, provides more details in this
regards.
To deal with detaching of a PM domain for the multiple PM domains case,
let's also extend the existing genpd_dev_pm_detach() function, to cover the
cleanup of the created virtual device, via make it call device_unregister()
on it. In this way, there is no need to introduce a new function to deal
with detach for the multiple PM domain case, but instead the existing one
is re-used.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
To extend genpd to deal with allowing multiple PM domains per device, some
of the code in genpd_dev_pm_attach() can be re-used. Let's prepare for this
by moving some of the code into a sub-function.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The power-domain DT property may now contain a list of PM domain
specifiers, which represents that a device are partitioned across multiple
PM domains. This leads to a new situation in genpd_dev_pm_attach(), as only
one PM domain can be attached per device.
To remain things simple for the most common configuration, when a single PM
domain is used, let's treat the multiple PM domain case as being specific.
In other words, let's change genpd_dev_pm_attach() to check for multiple PM
domains and prevent it from attach any PM domain for this case. Instead,
leave this to be managed separately, from following changes to genpd.
Suggested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Here is the driver core patchset for 4.18-rc1.
The large chunk of these are firmware core documentation and api
updates. Nothing major there, just better descriptions for others to be
able to understand the firmware code better. There's also a user for a
new firmware api call.
Other than that, there are some minor updates for debugfs, kernfs, and
the driver core itself.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the driver core patchset for 4.18-rc1.
The large chunk of these are firmware core documentation and api
updates. Nothing major there, just better descriptions for others to
be able to understand the firmware code better. There's also a user
for a new firmware api call.
Other than that, there are some minor updates for debugfs, kernfs, and
the driver core itself.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits)
driver core: hold dev's parent lock when needed
driver-core: return EINVAL error instead of BUG_ON()
driver core: add __printf verification to device_create_groups_vargs
mm: memory_hotplug: use put_device() if device_register fail
base: core: fix typo 'can by' to 'can be'
debugfs: inode: debugfs_create_dir uses mode permission from parent
debugfs: Re-use kstrtobool_from_user()
Documentation: clarify firmware_class provenance and why we can't rename the module
Documentation: remove stale firmware API reference
Documentation: fix few typos and clarifications for the firmware loader
ath10k: re-enable the firmware fallback mechanism for testmode
ath10k: use firmware_request_nowarn() to load firmware
firmware: add firmware_request_nowarn() - load firmware without warnings
firmware_loader: make firmware_fallback_sysfs() print more useful
firmware_loader: move kconfig FW_LOADER entries to its own file
firmware_loader: replace ---help--- with help
firmware_loader: enhance Kconfig documentation over FW_LOADER
firmware_loader: document firmware_sysfs_fallback()
firmware: rename fw_sysfs_fallback to firmware_fallback_sysfs()
firmware: use () to terminate kernel-doc function names
...
Use the overflow helpers both in existing multiplication-using inlines as
well as the addition-overflow case in the core allocation routine.
Signed-off-by: Kees Cook <keescook@chromium.org>
Modify the device properties framework to remove union aliasing
from it (Andy Shevchenko).
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Merge tag 'dp-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull device properties framework update from Rafael Wysocki:
"Modify the device properties framework to remove union aliasing from
it (Andy Shevchenko)"
* tag 'dp-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
device property: Get rid of union aliasing
These include a significant update of the generic power domains (genpd)
and Operating Performance Points (OPP) frameworks, mostly related to
the introduction of power domain performance levels, cpufreq updates
(new driver for Qualcomm Kryo processors, updates of the existing
drivers, some core fixes, schedutil governor improvements), PCI power
management fixes, ACPI workaround for EC-based wakeup events handling
on resume from suspend-to-idle, and major updates of the turbostat
and pm-graph utilities.
Specifics:
- Introduce power domain performance levels into the the generic
power domains (genpd) and Operating Performance Points (OPP)
frameworks (Viresh Kumar, Rajendra Nayak, Dan Carpenter).
- Fix two issues in the runtime PM framework related to the
initialization and removal of devices using device links (Ulf
Hansson).
- Clean up the initialization of drivers for devices in PM domains
(Ulf Hansson, Geert Uytterhoeven).
- Fix a cpufreq core issue related to the policy sysfs interface
causing CPU online to fail for CPUs sharing one cpufreq policy in
some situations (Tao Wang).
- Make it possible to use platform-specific suspend/resume hooks
in the cpufreq-dt driver and make the Armada 37xx DVFS use that
feature (Viresh Kumar, Miquel Raynal).
- Optimize policy transition notifications in cpufreq (Viresh Kumar).
- Improve the iowait boost mechanism in the schedutil cpufreq
governor (Patrick Bellasi).
- Improve the handling of deferred frequency updates in the
schedutil cpufreq governor (Joel Fernandes, Dietmar Eggemann,
Rafael Wysocki, Viresh Kumar).
- Add a new cpufreq driver for Qualcomm Kryo (Ilia Lin).
- Fix and clean up some cpufreq drivers (Colin Ian King, Dmitry
Osipenko, Doug Smythies, Luc Van Oostenryck, Simon Horman,
Viresh Kumar).
- Fix the handling of PCI devices with the DPM_SMART_SUSPEND flag
set and update stale comments in the PCI core PM code (Rafael
Wysocki).
- Work around an issue related to the handling of EC-based wakeup
events in the ACPI PM core during resume from suspend-to-idle if
the EC has been put into the low-power mode (Rafael Wysocki).
- Improve the handling of wakeup source objects in the PM core (Doug
Berger, Mahendran Ganesh, Rafael Wysocki).
- Update the driver core to prevent deferred probe from breaking
suspend/resume ordering (Feng Kan).
- Clean up the PM core somewhat (Bjorn Helgaas, Ulf Hansson, Rafael
Wysocki).
- Make the core suspend/resume code and cpufreq support the RT patch
(Sebastian Andrzej Siewior, Thomas Gleixner).
- Consolidate the PM QoS handling in cpuidle governors (Rafael
Wysocki).
- Fix a possible crash in the hibernation core (Tetsuo Handa).
- Update the rockchip-io Adaptive Voltage Scaling (AVS) driver
(David Wu).
- Update the turbostat utility (fixes, cleanups, new CPU IDs, new
command line options, built-in "Low Power Idle" counters support,
new POLL and POLL% columns) and add an entry for it to MAINTAINERS
(Len Brown, Artem Bityutskiy, Chen Yu, Laura Abbott, Matt Turner,
Prarit Bhargava, Srinivas Pandruvada).
- Update the pm-graph to version 5.1 (Todd Brandt).
- Update the intel_pstate_tracer utility (Doug Smythies).
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Merge tag 'pm-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These include a significant update of the generic power domains
(genpd) and Operating Performance Points (OPP) frameworks, mostly
related to the introduction of power domain performance levels,
cpufreq updates (new driver for Qualcomm Kryo processors, updates of
the existing drivers, some core fixes, schedutil governor
improvements), PCI power management fixes, ACPI workaround for
EC-based wakeup events handling on resume from suspend-to-idle, and
major updates of the turbostat and pm-graph utilities.
Specifics:
- Introduce power domain performance levels into the the generic
power domains (genpd) and Operating Performance Points (OPP)
frameworks (Viresh Kumar, Rajendra Nayak, Dan Carpenter).
- Fix two issues in the runtime PM framework related to the
initialization and removal of devices using device links (Ulf
Hansson).
- Clean up the initialization of drivers for devices in PM domains
(Ulf Hansson, Geert Uytterhoeven).
- Fix a cpufreq core issue related to the policy sysfs interface
causing CPU online to fail for CPUs sharing one cpufreq policy in
some situations (Tao Wang).
- Make it possible to use platform-specific suspend/resume hooks in
the cpufreq-dt driver and make the Armada 37xx DVFS use that
feature (Viresh Kumar, Miquel Raynal).
- Optimize policy transition notifications in cpufreq (Viresh Kumar).
- Improve the iowait boost mechanism in the schedutil cpufreq
governor (Patrick Bellasi).
- Improve the handling of deferred frequency updates in the schedutil
cpufreq governor (Joel Fernandes, Dietmar Eggemann, Rafael Wysocki,
Viresh Kumar).
- Add a new cpufreq driver for Qualcomm Kryo (Ilia Lin).
- Fix and clean up some cpufreq drivers (Colin Ian King, Dmitry
Osipenko, Doug Smythies, Luc Van Oostenryck, Simon Horman, Viresh
Kumar).
- Fix the handling of PCI devices with the DPM_SMART_SUSPEND flag set
and update stale comments in the PCI core PM code (Rafael Wysocki).
- Work around an issue related to the handling of EC-based wakeup
events in the ACPI PM core during resume from suspend-to-idle if
the EC has been put into the low-power mode (Rafael Wysocki).
- Improve the handling of wakeup source objects in the PM core (Doug
Berger, Mahendran Ganesh, Rafael Wysocki).
- Update the driver core to prevent deferred probe from breaking
suspend/resume ordering (Feng Kan).
- Clean up the PM core somewhat (Bjorn Helgaas, Ulf Hansson, Rafael
Wysocki).
- Make the core suspend/resume code and cpufreq support the RT patch
(Sebastian Andrzej Siewior, Thomas Gleixner).
- Consolidate the PM QoS handling in cpuidle governors (Rafael
Wysocki).
- Fix a possible crash in the hibernation core (Tetsuo Handa).
- Update the rockchip-io Adaptive Voltage Scaling (AVS) driver (David
Wu).
- Update the turbostat utility (fixes, cleanups, new CPU IDs, new
command line options, built-in "Low Power Idle" counters support,
new POLL and POLL% columns) and add an entry for it to MAINTAINERS
(Len Brown, Artem Bityutskiy, Chen Yu, Laura Abbott, Matt Turner,
Prarit Bhargava, Srinivas Pandruvada).
- Update the pm-graph to version 5.1 (Todd Brandt).
- Update the intel_pstate_tracer utility (Doug Smythies)"
* tag 'pm-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (128 commits)
tools/power turbostat: update version number
tools/power turbostat: Add Node in output
tools/power turbostat: add node information into turbostat calculations
tools/power turbostat: remove num_ from cpu_topology struct
tools/power turbostat: rename num_cores_per_pkg to num_cores_per_node
tools/power turbostat: track thread ID in cpu_topology
tools/power turbostat: Calculate additional node information for a package
tools/power turbostat: Fix node and siblings lookup data
tools/power turbostat: set max_num_cpus equal to the cpumask length
tools/power turbostat: if --num_iterations, print for specific number of iterations
tools/power turbostat: Add Cannon Lake support
tools/power turbostat: delete duplicate #defines
x86: msr-index.h: Correct SNB_C1/C3_AUTO_UNDEMOTE defines
tools/power turbostat: Correct SNB_C1/C3_AUTO_UNDEMOTE defines
tools/power turbostat: add POLL and POLL% column
tools/power turbostat: Fix --hide Pk%pc10
tools/power turbostat: Build-in "Low Power Idle" counters support
tools/power turbostat: Don't make man pages executable
tools/power turbostat: remove blank lines
tools/power turbostat: a small C-states dump readability immprovement
...
Pull irq updates from Thomas Gleixner:
- Consolidation of softirq pending:
The softirq mask and its accessors/mutators have many implementations
scattered around many architectures. Most do the same things
consisting in a field in a per-cpu struct (often irq_cpustat_t)
accessed through per-cpu ops. We can provide instead a generic
efficient version that most of them can use. In fact s390 is the only
exception because the field is stored in lowcore.
- Support for level!?! triggered MSI (ARM)
Over the past couple of years, we've seen some SoCs coming up with
ways of signalling level interrupts using a new flavor of MSIs, where
the MSI controller uses two distinct messages: one that raises a
virtual line, and one that lowers it. The target MSI controller is in
charge of maintaining the state of the line.
This allows for a much simplified HW signal routing (no need to have
hundreds of discrete lines to signal level interrupts if you already
have a memory bus), but results in a departure from the current idea
the kernel has of MSIs.
- Support for Meson-AXG GPIO irqchip
- Large stm32 irqchip rework (suspend/resume, hierarchical domains)
- More SPDX conversions
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
ARM: dts: stm32: Add exti support to stm32mp157 pinctrl
ARM: dts: stm32: Add exti support for stm32mp157c
pinctrl/stm32: Add irq_eoi for stm32gpio irqchip
irqchip/stm32: Add suspend/resume support for hierarchy domain
irqchip/stm32: Add stm32mp1 support with hierarchy domain
irqchip/stm32: Prepare common functions
irqchip/stm32: Add host and driver data structures
irqchip/stm32: Add suspend support
irqchip/stm32: Add falling pending register support
irqchip/stm32: Checkpatch fix
irqchip/stm32: Optimizes and cleans up stm32-exti irq_domain
irqchip/meson-gpio: Add support for Meson-AXG SoCs
dt-bindings: interrupt-controller: New binding for Meson-AXG SoC
dt-bindings: interrupt-controller: Fix the double quotes
softirq/s390: Move default mutators of overwritten softirq mask to s390
softirq/x86: Switch to generic local_softirq_pending() implementation
softirq/sparc: Switch to generic local_softirq_pending() implementation
softirq/powerpc: Switch to generic local_softirq_pending() implementation
softirq/parisc: Switch to generic local_softirq_pending() implementation
softirq/ia64: Switch to generic local_softirq_pending() implementation
...
This is another quiet release for regmap, there's one minor feature
improvement for the recently added slimbus support and a few minor fixes
and cleanups.
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Merge tag 'regmap-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap updates from Mark Brown:
"This is another quiet release for regmap, there's one minor feature
improvement for the recently added slimbus support and a few minor
fixes and cleanups"
* tag 'regmap-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: slimbus: allow register offsets up to 16 bits
regmap: add missing prototype for devm_init_slimbus
regmap: Skip clk_put for attached clocks when freeing context
regmap: include <linux/ktime.h> from include/linux/regmap.h
- replaceme the force_dma flag with a dma_configure bus method.
(Nipun Gupta, although one patch is іncorrectly attributed to me
due to a git rebase bug)
- use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)
- remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
right thing for bounce buffering.
- move dma-debug initialization to common code, and apply a few cleanups
to the dma-debug code.
- cleanup the Kconfig mess around swiotlb selection
- swiotlb comment fixup (Yisheng Xie)
- a trivial swiotlb fix. (Dan Carpenter)
- support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)
- add a new generic dma-noncoherent dma_map_ops implementation and use
it for arc, c6x and nds32.
- improve scatterlist validity checking in dma-debug. (Robin Murphy)
- add a struct device quirk to limit the dma-mask to 32-bit due to
bridge/system issues, and switch x86 to use it instead of a local
hack for VIA bridges.
- handle devices without a dma_mask more gracefully in the dma-direct
code.
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Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- replace the force_dma flag with a dma_configure bus method. (Nipun
Gupta, although one patch is іncorrectly attributed to me due to a
git rebase bug)
- use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)
- remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
right thing for bounce buffering.
- move dma-debug initialization to common code, and apply a few
cleanups to the dma-debug code.
- cleanup the Kconfig mess around swiotlb selection
- swiotlb comment fixup (Yisheng Xie)
- a trivial swiotlb fix. (Dan Carpenter)
- support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)
- add a new generic dma-noncoherent dma_map_ops implementation and use
it for arc, c6x and nds32.
- improve scatterlist validity checking in dma-debug. (Robin Murphy)
- add a struct device quirk to limit the dma-mask to 32-bit due to
bridge/system issues, and switch x86 to use it instead of a local
hack for VIA bridges.
- handle devices without a dma_mask more gracefully in the dma-direct
code.
* tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits)
dma-direct: don't crash on device without dma_mask
nds32: use generic dma_noncoherent_ops
nds32: implement the unmap_sg DMA operation
nds32: consolidate DMA cache maintainance routines
x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag
x86/pci-dma: remove the explicit nodac and allowdac option
x86/pci-dma: remove the experimental forcesac boot option
Documentation/x86: remove a stray reference to pci-nommu.c
core, dma-direct: add a flag 32-bit dma limits
dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs
dma-debug: check scatterlist segments
c6x: use generic dma_noncoherent_ops
arc: use generic dma_noncoherent_ops
arc: fix arc_dma_{map,unmap}_page
arc: fix arc_dma_sync_sg_for_{cpu,device}
arc: simplify arc_dma_sync_single_for_{cpu,device}
dma-mapping: provide a generic dma-noncoherent implementation
dma-mapping: simplify Kconfig dependencies
riscv: add swiotlb support
riscv: only enable ZONE_DMA32 for 64-bit
...
* pm-pci:
PCI / PM: Clean up outdated comments in pci_target_state()
PCI / PM: Do not clear state_saved for devices that remain suspended
* acpi-pm:
ACPI: EC: Dispatch the EC GPE directly on s2idle wake
ACPICA: Introduce acpi_dispatch_gpe()
* pm-sleep:
PM / hibernate: Fix oops at snapshot_write()
PM / wakeup: Make s2idle_lock a RAW_SPINLOCK
PM / s2idle: Make s2idle_wait_head swait based
PM / wakeup: Make events_lock a RAW_SPINLOCK
PM / suspend: Prevent might sleep splats
* pm-avs:
PM / AVS: rockchip-io: add io selectors and supplies for PX30
* pm-opp: (24 commits)
PM / Domains: Drop unused parameter in genpd_allocate_dev_data()
PM / Domains: Drop genpd as in-param for pm_genpd_remove_device()
PM / Domains: Drop __pm_genpd_add_device()
PM / Domains: Drop extern declarations of functions in pm_domain.h
PM / domains: Add perf_state attribute to genpd debugfs
OPP: Allow same OPP table to be used for multiple genpd
PM / Domain: Return 0 on error from of_genpd_opp_to_performance_state()
PM / OPP: Fix shared OPP table support in dev_pm_opp_register_set_opp_helper()
PM / OPP: Fix shared OPP table support in dev_pm_opp_set_regulators()
PM / OPP: Fix shared OPP table support in dev_pm_opp_set_prop_name()
PM / OPP: Fix shared OPP table support in dev_pm_opp_set_supported_hw()
PM / OPP: silence an uninitialized variable warning
PM / OPP: Remove dev_pm_opp_{un}register_get_pstate_helper()
PM / OPP: Get performance state using genpd helper
PM / Domain: Implement of_genpd_opp_to_performance_state()
PM / Domain: Add support to parse domain's OPP table
PM / Domain: Add struct device to genpd
PM / OPP: Implement dev_pm_opp_get_of_node()
PM / OPP: Implement of_dev_pm_opp_find_required_opp()
PM / OPP: Implement dev_pm_opp_of_add_table_indexed()
...
* pm-domains:
PM / domains: Improve wording of dev_pm_domain_attach() comment
PM / Domains: Don't return -EEXIST at attach when PM domain exists
spi: Respect all error codes from dev_pm_domain_attach()
soundwire: Respect all error codes from dev_pm_domain_attach()
mmc: sdio: Respect all error codes from dev_pm_domain_attach()
i2c: Respect all error codes from dev_pm_domain_attach()
driver core: Respect all error codes from dev_pm_domain_attach()
amba: Respect all error codes from dev_pm_domain_attach()
PM / Domains: Allow a better error handling of dev_pm_domain_attach()
PM / Domains: Check for existing PM domain in dev_pm_domain_attach()
PM / Domains: Drop redundant code in genpd while attaching devices
PM / Domains: Drop comment in genpd about legacy Samsung DT binding
PM / Domains: Fix error path during attach in genpd
* pm-qos:
PM / QoS: Drop redundant declaration of pm_qos_get_value()
* pm-core:
PM / runtime: Drop usage count for suppliers at device link removal
PM / runtime: Fixup reference counting of device link suppliers at probe
PM: wakeup: Use pr_debug() for the "aborting suspend" message
PM / core: Drop unused internal inline functions for sysfs
PM / core: Drop unused internal functions for pm_qos sysfs
PM / core: Drop unused internal inline functions for wakeirqs
PM / core: Drop internal unused inline functions for wakeups
PM / wakeup: Only update last time for active wakeup sources
PM / wakeup: Use seq_open() to show wakeup stats
PM / core: Use dev_printk() and symbols in suspend/resume diagnostics
PM / core: Simplify initcall_debug_report() timing
PM / core: Remove unused initcall_debug_report() arguments
PM / core: fix deferred probe breaking suspend resume order
SoC have internal I/O buses that can't be proved for devices. The
devices on the buses can be accessed directly without additinal
configuration required. This type of bus is represented as
"simple-bus". In some platforms, we name "soc" with "simple-bus"
attribute and many devices are hooked under it described in DT
(device tree).
In commit bf74ad5bc4 ("Hold the device's parent's lock during
probe and remove") to solve USB subsystem lock sequence since
USB device's characteristic. Thus "soc" needs to be locked
whenever a device and driver's probing happen under "soc" bus.
During this period, an async driver tries to probe a device which
is under the "soc" bus would be blocked until previous driver
finish the probing and release "soc" lock. And the next probing
under the "soc" bus need to wait for async finish. Because of
that, driver's async probe for init time improvement will be
shadowed.
Since many devices don't have USB devices' characteristic, they
actually don't need parent's lock. Thus, we introduce a lock flag
in bus_type struct and driver core would lock the parent lock base
on the flag. For USB, we set this flag in usb_bus_type to keep
original lock behavior in driver core.
Async probe could have more benefit after this patch.
Signed-off-by: Martin Liu <liumartin@google.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The in-parameter struct generic_pm_domain *genpd to
genpd_allocate_dev_data() is unused, so let's drop it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is no need to pass a genpd struct to pm_genpd_remove_device(), as we
already have the information about the PM domain (genpd) through the device
structure.
Additionally, we don't allow to remove a PM domain from a device, other
than the one it may have assigned to it, so really it does not make sense
to have a separate in-param for it.
For these reason, drop it and update the current only call to
pm_genpd_remove_device() from amdgpu_acp.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are still a few non-DT existing users of genpd, however neither of
them uses __pm_genpd_add_device(), hence let's drop it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Now that genpd supports performance states, add this additional
attribute as part of the power domains debugfs entry, to display
the current performance state for the Power domain.
Suggested-by: David Collins <collinsd@codeaurora.org>
Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the case consumer device is runtime resumed, while the link to the
supplier is removed, the earlier call to pm_runtime_get_sync() made from
rpm_get_suppliers() does not get properly balanced with a corresponding
call to pm_runtime_put(). This leads to that suppliers remains to be
runtime resumed forever, while they don't need to.
Let's fix the behaviour by calling rpm_put_suppliers() when dropping a
device link. Not that, since rpm_put_suppliers() checks the
link->rpm_active flag, we can correctly avoid to call pm_runtime_put() in
cases when we shouldn't.
Reported-by: Todor Tomov <todor.tomov@linaro.org>
Fixes: 21d5c57b37 (PM / runtime: Use device links)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the driver core, before it invokes really_probe() it runtime resumes the
suppliers for the device via calling pm_runtime_get_suppliers(), which also
increases the runtime PM usage count for each of the available supplier.
This makes sense, as to be able to allow the consumer device to be probed
by its driver. However, if the driver decides to add a new supplier link
during ->probe(), hence updating the list of suppliers, the following call
to pm_runtime_put_suppliers(), invoked after really_probe() in the driver
core, we get into trouble.
More precisely, pm_runtime_put() gets called also for the new supplier(s),
which is wrong as the driver core, didn't trigger pm_runtime_get_sync() to
be called for it in the first place. In other words, the new supplier may
be runtime suspended even in cases when it shouldn't.
Fix this behaviour, by runtime resume suppliers according to the same
conditions as managed by the runtime PM core, when runtime resume callbacks
are being invoked.
Additionally, don't try to runtime suspend any of the suppliers after
really_probe(), but instead rely on that to happen via the consumer device,
when it becomes runtime suspended.
Fixes: 21d5c57b37 (PM / runtime: Use device links)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The `events_lock' is acquired during suspend while interrupts are
disabled even on RT. The lock is taken only for a very brief moment.
Make it a RAW lock which avoids "sleeping while atomic" warnings on RT.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The case of a new numa node got missed in avoiding using the node info
from page_struct during hotplug. In this path we have a call to
register_mem_sect_under_node (which allows us to specify it is hotplug
so don't change the node), via link_mem_sections which unfortunately
does not.
Fix is to pass check_nid through link_mem_sections as well and disable
it in the new numa node path.
Note the bug only 'sometimes' manifests depending on what happens to be
in the struct page structures - there are lots of them and it only needs
to match one of them.
The result of the bug is that (with a new memory only node) we never
successfully call register_mem_sect_under_node so don't get the memory
associated with the node in sysfs and meminfo for the node doesn't
report it.
It came up whilst testing some arm64 hotplug patches, but appears to be
universal. Whilst I'm triggering it by removing then reinserting memory
to a node with no other elements (thus making the node disappear then
appear again), it appears it would happen on hotplugging memory where
there was none before and it doesn't seem to be related the arm64
patches.
These patches call __add_pages (where most of the issue was fixed by
Pavel's patch). If there is a node at the time of the __add_pages call
then all is well as it calls register_mem_sect_under_node from there
with check_nid set to false. Without a node that function returns
having not done the sysfs related stuff as there is no node to use.
This is expected but it is the resulting path that fails...
Exact path to the problem is as follows:
mm/memory_hotplug.c: add_memory_resource()
The node is not online so we enter the 'if (new_node)' twice, on the
second such block there is a call to link_mem_sections which calls
into
drivers/node.c: link_mem_sections() which calls
drivers/node.c: register_mem_sect_under_node() which calls
get_nid_for_pfn and keeps trying until the output of that matches
the expected node (passed all the way down from
add_memory_resource)
It is effectively the same fix as the one referred to in the fixes tag
just in the code path for a new node where the comments point out we
have to rerun the link creation because it will have failed in
register_new_memory (as there was no node at the time). (actually that
comment is wrong now as we don't have register_new_memory any more it
got renamed to hotplug_memory_register in Pavel's patch).
Link: http://lkml.kernel.org/r/20180504085311.1240-1-Jonathan.Cameron@huawei.com
Fixes: fc44f7f923 ("mm/memory_hotplug: don't read nid from struct page during hotplug")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As per SLIMBus specs Value Elements and Information Elements
address map ranges from 0x000 - 0xFFF.
So allow register addresses up to 16 bits
Fixes: 7d6f7fb053 ("regmap: add SLIMbus support")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
I triggerd the BUG_ON() in driver_register() when booting a domU Xen
domain. Since there was no contextual information logged, I needed to
attach kgdb to determine the culprit (the wmi-bmof driver in my
case). The BUG_ON() was added in commit f48f3febb2 ("driver-core: do
not register a driver with bus_type not registered").
Instead of running into a BUG_ON() we print an error message
identifying the, likely faulty, driver but continue booting.
Signed-off-by: Florian Schmaus <flo@geekplace.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
of_genpd_opp_to_performance_state() should return 0 on errors, as its
doc comment describes. While it follows that mostly, it returns a
negative error number on one of the failures.
Fix that.
Fixes: 6e41766a6a "PM / Domain: Implement of_genpd_opp_to_performance_state()"
Reported-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix a regression from the 4.15 cycle that caused the system suspend
and resume overhead to increase on many systems and triggered more
serious problems on some of them (Rafael Wysocki).
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Merge tag 'pm-4.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fix from Rafael Wysocki:
"Fix a regression from the 4.15 cycle that caused the system suspend
and resume overhead to increase on many systems and triggered more
serious problems on some of them (Rafael Wysocki)"
* tag 'pm-4.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / core: Fix direct_complete handling for devices with no callbacks
The message printed by pm_wakeup_pending() on wakeup detection is
not very useful if someone is not interested specifically in
debugging wakeup, so turn it into a pm_debug() one.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 08810a4119 (PM / core: Add NEVER_SKIP and SMART_PREPARE
driver flags) inadvertently prevented the power.direct_complete flag
from being set for devices without PM callbacks and with disabled
runtime PM which also prevents power.direct_complete from being set
for their parents. That led to problems including a resume crash on
HP ZBook 14u.
Restore the previous behavior by causing power.direct_complete to be
set for those devices again, but do that in a more direct way to
avoid overlooking that case in the future.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=199693
Fixes: 08810a4119 (PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags)
Reported-by: Thomas Martitz <kugel@rockbox.org>
Tested-by: Thomas Martitz <kugel@rockbox.org>
Cc: 4.15+ <stable@vger.kernel.org> # 4.15+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Johan Hovold <johan@kernel.org>
Call ACPI cache parsing routines from base cacheinfo code if ACPI
is enabled. Also stub out cache_setup_acpi and acpi_find_last_cache_level
so that individual architectures can enable ACPI topology parsing.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Vijaya Kumar K <vkilari@codeaurora.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Tested-by: Tomasz Nowicki <Tomasz.Nowicki@cavium.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Rename and change the type of of_node to indicate
it is a generic pointer which is generally only used
for comparison purposes. In a later patch we will put
an ACPI/PPTT token pointer in fw_token so that
the code which builds the shared cpu masks can be reused.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Vijaya Kumar K <vkilari@codeaurora.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Tested-by: Tomasz Nowicki <Tomasz.Nowicki@cavium.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The original intent in cacheinfo was that an architecture
specific populate_cache_leaves() would probe the hardware
and then cache_shared_cpu_map_setup() and
cache_override_properties() would provide firmware help to
extend/expand upon what was probed. Arm64 was really
the only architecture that was working this way, and
with the removal of most of the hardware probing logic it
became clear that it was possible to simplify the logic a bit.
This patch combines the walk of the DT nodes with the
code updating the cache size/line_size and nr_sets.
cache_override_properties() (which was DT specific) is
then removed. The result is that cacheinfo.of_node is
no longer used as a temporary place to hold DT references
for future calls that update cache properties. That change
helps to clarify its one remaining use (matching
cacheinfo nodes that represent shared caches) which
will be used by the ACPI/PPTT code in the following patches.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Vijaya Kumar K <vkilari@codeaurora.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Tested-by: Tomasz Nowicki <Tomasz.Nowicki@cavium.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In preparation for the next patch, and to aid in
review of that patch, lets move cache_setup_of_node
further down in the module without any changes.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Vijaya Kumar K <vkilari@codeaurora.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Tested-by: Tomasz Nowicki <Tomasz.Nowicki@cavium.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Commit 318a197182 (device property: refactor built-in properties
support) went way too far and brought a union aliasing. Partially
revert it here to get rid of union aliasing.
Note, all Apple properties are considered as u8 arrays. To get a value
of any of them the caller must use device_property_read_u8_array().
What's union aliasing?
~~~~~~~~~~~~~~~~~~~~~~
The C99 standard in section 6.2.5 paragraph 20 defines union type as
"an overlapping nonempty set of member objects". It also states in
section 6.7.2.1 paragraph 14 that "the value of at most one of the
members can be stored in a union object at any time'.
Union aliasing is a type punning mechanism using union members to store
as one type and read back as another.
Why it's not good?
~~~~~~~~~~~~~~~~~~
Section 6.2.6.1 paragraph 6 says that a union object may not be a trap
representation, although its member objects may be.
Meanwhile annex J.1 says that "the value of a union member other than
the last one stored into" is unspecified [removed in C11].
In TC3, a footnote is added which specifies that accessing a member of a
union other than the last one stored causes "the object representation"
to be re-interpreted in the new type and specifically refers to this as
"type punning". This conflicts to some degree with Annex J.1.
While it's working in Linux with GCC, the use of union members to do
type punning is not clear area in the C standard and might lead to
unspecified behaviour.
More information is available in this [1] blog post.
[1]: https://davmac.wordpress.com/2010/02/26/c99-revisited/
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
