Some systems don't support the ACPI_LPS0_ENTRY and ACPI_LPS0_EXIT
functions in their Low Power S0 Idle _DSM, but still expect EC
events to be processed in the suspend-to-idle state for power button
wakeup (among other things) to work. Surface Pro3 turns out to be
one of them.
Fortunately, it still provides Low Power S0 Idle _DSM with the screen
on/off functions supported, so modify the ACPI suspend-to-idle to use
the Low Power S0 Idle code path for all systems supporting the
ACPI_LPS0_ENTRY and ACPI_LPS0_EXIT or the ACPI_LPS0_SCREEN_OFF and
ACPI_LPS0_SCREEN_ON functions in their Low Power S0 Idle _DSM.
Potentially, that will cause more systems to use suspend-to-idle by
default, so some future corrections may be necessary if it leads
to issues, but let it remain more straightforward for now.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=198389#add_comment
Reported-by: Valentin Manea <valy@mrs.ro>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Valentin Manea <valy@mrs.ro>
The ACPI code supporting system transitions to sleep states uses
an internal blacklist to apply special handling to some machines
reported to behave incorrectly in some ways.
However, some entries of that blacklist cover problematic as well as
non-problematic systems, so give the users of the latter a chance to
ignore the blacklist and run their systems in the default way by
adding acpi_sleep=nobl to the kernel command line.
For example, that allows the users of Dell XPS13 9360 systems not
affected by the issue that caused the blacklist entry for this
machine to be added by commit 71630b7a83 (ACPI / PM: Blacklist Low
Power S0 Idle _DSM for Dell XPS13 9360) to use suspend-to-idle with
the Low Power S0 Idle _DSM interface which in principle should be
more energy-efficient than S3 on them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
At least one Dell XPS13 9360 is reported to have serious issues with
the Low Power S0 Idle _DSM interface and since this machine model
generally can do ACPI S3 just fine, add a blacklist entry to disable
that interface for Dell XPS13 9360.
Fixes: 8110dd281e (ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196907
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 4.13+ <stable@vger.kernel.org> # 4.13+
... and __initconst if applicable.
Based on similar work for an older kernel in the Grsecurity patch.
[JD: fix toshiba-wmi build]
[JD: add htcpen]
[JD: move __initconst where checkscript wants it]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
- Update the ACPICA code in the kernel to upstream revision 20170728
including:
* Alias operator handling update (Bob Moore).
* Deferred resolution of reference package elements (Bob Moore).
* Support for the _DMA method in walk resources (Bob Moore).
* Tables handling update and support for deferred table
verification (Lv Zheng).
* Update of SMMU models for IORT (Robin Murphy).
* Compiler and disassembler updates (Alex James, Erik Schmauss,
Ganapatrao Kulkarni, James Morse).
* Tools updates (Erik Schmauss, Lv Zheng).
* Assorted minor fixes and cleanups (Bob Moore, Kees Cook,
Lv Zheng, Shao Ming).
- Rework the initialization of non-wakeup GPEs with method handlers
in order to address a boot crash on some systems with Thunderbolt
devices connected at boot time where we miss an early hotplug
event due to a delay in GPE enabling (Rafael Wysocki).
- Rework the handling of PCI bridges when setting up ACPI-based
device wakeup in order to avoid disabling wakeup for bridges
prematurely (Rafael Wysocki).
- Consolidate Apple DMI checks throughout the tree, add support for
Apple device properties to the device properties framework and
use these properties for the handling of I2C and SPI devices on
Apple systems (Lukas Wunner).
- Add support for _DMA to the ACPI-based device properties lookup
code and make it possible to use the information from there to
configure DMA regions on ARM64 systems (Lorenzo Pieralisi).
- Fix several issues in the APEI code, add support for exporting
the BERT error region over sysfs and update APEI MAINTAINERS
entry with reviewers information (Borislav Petkov, Dongjiu Geng,
Loc Ho, Punit Agrawal, Tony Luck, Yazen Ghannam).
- Fix a potential initialization ordering issue in the ACPI EC
driver and clean it up somewhat (Lv Zheng).
- Update the ACPI SPCR driver to extend the existing XGENE 8250
workaround in it to a new platform (m400) and to work around
an Xgene UART clock issue (Graeme Gregory).
- Add a new utility function to the ACPI core to support using
ACPI OEM ID / OEM Table ID / Revision for system identification
in blacklisting or similar and switch over the existing code
already using this information to this new interface (Toshi Kani).
- Fix an xpower PMIC issue related to GPADC reads that always return
0 without extra pin manipulations (Hans de Goede).
- Add statements to print debug messages in a couple of places in
the ACPI core for easier diagnostics (Rafael Wysocki).
- Clean up the ACPI processor driver slightly (Colin Ian King,
Hanjun Guo).
- Clean up the ACPI x86 boot code somewhat (Andy Shevchenko).
- Add a quirk for Dell OptiPlex 9020M to the ACPI backlight
driver (Alex Hung).
- Assorted fixes, cleanups and updates related to ACPI (Amitoj Kaur
Chawla, Bhumika Goyal, Frank Rowand, Jean Delvare, Punit Agrawal,
Ronald Tschalär, Sumeet Pawnikar).
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Merge tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
"These include a usual ACPICA code update (this time to upstream
revision 20170728), a fix for a boot crash on some systems with
Thunderbolt devices connected at boot time, a rework of the handling
of PCI bridges when setting up device wakeup, new support for Apple
device properties, support for DMA configurations reported via ACPI on
ARM64, APEI-related updates, ACPI EC driver updates and assorted minor
modifications in several places.
Specifics:
- Update the ACPICA code in the kernel to upstream revision 20170728
including:
* Alias operator handling update (Bob Moore).
* Deferred resolution of reference package elements (Bob Moore).
* Support for the _DMA method in walk resources (Bob Moore).
* Tables handling update and support for deferred table
verification (Lv Zheng).
* Update of SMMU models for IORT (Robin Murphy).
* Compiler and disassembler updates (Alex James, Erik Schmauss,
Ganapatrao Kulkarni, James Morse).
* Tools updates (Erik Schmauss, Lv Zheng).
* Assorted minor fixes and cleanups (Bob Moore, Kees Cook, Lv
Zheng, Shao Ming).
- Rework the initialization of non-wakeup GPEs with method handlers
in order to address a boot crash on some systems with Thunderbolt
devices connected at boot time where we miss an early hotplug event
due to a delay in GPE enabling (Rafael Wysocki).
- Rework the handling of PCI bridges when setting up ACPI-based
device wakeup in order to avoid disabling wakeup for bridges
prematurely (Rafael Wysocki).
- Consolidate Apple DMI checks throughout the tree, add support for
Apple device properties to the device properties framework and use
these properties for the handling of I2C and SPI devices on Apple
systems (Lukas Wunner).
- Add support for _DMA to the ACPI-based device properties lookup
code and make it possible to use the information from there to
configure DMA regions on ARM64 systems (Lorenzo Pieralisi).
- Fix several issues in the APEI code, add support for exporting the
BERT error region over sysfs and update APEI MAINTAINERS entry with
reviewers information (Borislav Petkov, Dongjiu Geng, Loc Ho, Punit
Agrawal, Tony Luck, Yazen Ghannam).
- Fix a potential initialization ordering issue in the ACPI EC driver
and clean it up somewhat (Lv Zheng).
- Update the ACPI SPCR driver to extend the existing XGENE 8250
workaround in it to a new platform (m400) and to work around an
Xgene UART clock issue (Graeme Gregory).
- Add a new utility function to the ACPI core to support using ACPI
OEM ID / OEM Table ID / Revision for system identification in
blacklisting or similar and switch over the existing code already
using this information to this new interface (Toshi Kani).
- Fix an xpower PMIC issue related to GPADC reads that always return
0 without extra pin manipulations (Hans de Goede).
- Add statements to print debug messages in a couple of places in the
ACPI core for easier diagnostics (Rafael Wysocki).
- Clean up the ACPI processor driver slightly (Colin Ian King, Hanjun
Guo).
- Clean up the ACPI x86 boot code somewhat (Andy Shevchenko).
- Add a quirk for Dell OptiPlex 9020M to the ACPI backlight driver
(Alex Hung).
- Assorted fixes, cleanups and updates related to ACPI (Amitoj Kaur
Chawla, Bhumika Goyal, Frank Rowand, Jean Delvare, Punit Agrawal,
Ronald Tschalär, Sumeet Pawnikar)"
* tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (75 commits)
ACPI / APEI: Suppress message if HEST not present
intel_pstate: convert to use acpi_match_platform_list()
ACPI / blacklist: add acpi_match_platform_list()
ACPI, APEI, EINJ: Subtract any matching Register Region from Trigger resources
ACPI: make device_attribute const
ACPI / sysfs: Extend ACPI sysfs to provide access to boot error region
ACPI: APEI: fix the wrong iteration of generic error status block
ACPI / processor: make function acpi_processor_check_duplicates() static
ACPI / EC: Clean up EC GPE mask flag
ACPI: EC: Fix possible issues related to EC initialization order
ACPI / PM: Add debug statements to acpi_pm_notify_handler()
ACPI: Add debug statements to acpi_global_event_handler()
ACPI / scan: Enable GPEs before scanning the namespace
ACPICA: Make it possible to enable runtime GPEs earlier
ACPICA: Dispatch active GPEs at init time
ACPI: SPCR: work around clock issue on xgene UART
ACPI: SPCR: extend XGENE 8250 workaround to m400
ACPI / LPSS: Don't abort ACPI scan on missing mem resource
mailbox: pcc: Drop uninformative output during boot
ACPI/IORT: Add IORT named component memory address limits
...
* pm-sleep:
ACPI / PM: Check low power idle constraints for debug only
PM / s2idle: Rename platform operations structure
PM / s2idle: Rename ->enter_freeze to ->enter_s2idle
PM / s2idle: Rename freeze_state enum and related items
PM / s2idle: Rename PM_SUSPEND_FREEZE to PM_SUSPEND_TO_IDLE
ACPI / PM: Prefer suspend-to-idle over S3 on some systems
platform/x86: intel-hid: Wake up Dell Latitude 7275 from suspend-to-idle
PM / suspend: Define pr_fmt() in suspend.c
PM / suspend: Use mem_sleep_labels[] strings in messages
PM / sleep: Put pm_test under CONFIG_PM_SLEEP_DEBUG
PM / sleep: Check pm_wakeup_pending() in __device_suspend_noirq()
PM / core: Add error argument to dpm_show_time()
PM / core: Split dpm_suspend_noirq() and dpm_resume_noirq()
PM / s2idle: Rearrange the main suspend-to-idle loop
PM / timekeeping: Print debug messages when requested
PM / sleep: Mark suspend/hibernation start and finish
PM / sleep: Do not print debug messages by default
PM / suspend: Export pm_suspend_target_state
For SoC to achieve its lowest power platform idle state a set of hardware
preconditions must be met. These preconditions or constraints can be
obtained by issuing a device specific method (_DSM) with function "1".
Refer to the document provided in the link below.
Here during initialization (from attach() callback of LPS0 device), invoke
function 1 to get the device constraints. Each enabled constraint is
stored in a table.
The devices in this table are used to check whether they were in required
minimum state, while entering suspend. This check is done from platform
freeze wake() callback, only when /sys/power/pm_debug_messages attribute
is non zero.
If any constraint is not met and device is ACPI power managed then it
prints the device information to kernel logs.
Also if debug is enabled in acpi/sleep.c, the constraint table and state
of each device on wake is dumped in kernel logs.
Since pm_debug_messages_on setting is used as condition to check
constraints outside kernel/power/main.c, pm_debug_messages_on is changed
to a global variable.
Link: http://www.uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rename struct platform_freeze_ops to platform_s2idle_ops to make it
clear that the callbacks in it are used during suspend-to-idle
suspend/resume transitions and rename the related functions,
variables and so on accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
To make it clear that the symbol in question refers to
suspend-to-idle, rename it from PM_SUSPEND_FREEZE to
PM_SUSPEND_TO_IDLE.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Modify the ACPI system sleep support setup code to select
suspend-to-idle as the default system sleep state if
(1) the ACPI_FADT_LOW_POWER_S0 flag is set in the FADT and
(2) the Low Power Idle S0 _DSM interface has been discovered and
(3) the default sleep state was not selected from the kernel command
line.
The main motivation for this change is that systems where the (1) and
(2) conditions are met typically ship with OSes that don't exercise
the S3 path in the platform firmware which remains untested and turns
out to be non-functional at least in some cases.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@dell.com>
Function acpi_sleep_syscore_init has no external user so it should be
static.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit eed4d47efe (ACPI / sleep: Ignore spurious SCI wakeups from
suspend-to-idle) introduced acpi_freeze_sync() whose purpose is to
flush all of the processing of possible wakeup events signaled via
the ACPI SCI. However, it doesn't flush the query workqueue used
by the EC driver, so the events generated by the EC may not be
processed timely which leads to issues (increased overhead at least,
lost events possibly).
To fix that introduce acpi_ec_flush_work() that will flush all of
the outstanding EC work and call it from acpi_freeze_sync().
Fixes: eed4d47efe (ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some recent Dell laptops, including the XPS13 model numbers 9360 and
9365, cannot be woken up from suspend-to-idle by pressing the power
button which is unexpected and makes that feature less usable on
those systems. Moreover, on the 9365 ACPI S3 (suspend-to-RAM) is
not expected to be used at all (the OS these systems ship with never
exercises the ACPI S3 path in the firmware) and suspend-to-idle is
the only viable system suspend mechanism there.
The reason why the power button wakeup from suspend-to-idle doesn't
work on those systems is because their power button events are
signaled by the EC (Embedded Controller), whose GPE (General Purpose
Event) line is disabled during suspend-to-idle transitions in Linux.
That is done on purpose, because in general the EC tends to be noisy
for various reasons (battery and thermal updates and similar, for
example) and all events signaled by it would kick the CPUs out of
deep idle states while in suspend-to-idle, which effectively might
defeat its purpose.
Of course, on the Dell systems in question the EC GPE must be enabled
during suspend-to-idle transitions for the button press events to
be signaled while suspended at all, but fortunately there is a way
out of this puzzle.
First of all, those systems have the ACPI_FADT_LOW_POWER_S0 flag set
in their ACPI tables, which means that the OS is expected to prefer
the "low power S0 idle" system state over ACPI S3 on them. That
causes the most recent versions of other OSes to simply ignore ACPI
S3 on those systems, so it is reasonable to expect that it should not
be necessary to block GPEs during suspend-to-idle on them.
Second, in addition to that, the systems in question provide a special
firmware interface that can be used to indicate to the platform that
the OS is transitioning into a system-wide low-power state in which
certain types of activity are not desirable or that it is leaving
such a state and that (in principle) should allow the platform to
adjust its operation mode accordingly.
That interface is a special _DSM object under a System Power
Management Controller device (PNP0D80). The expected way to use it
is to invoke function 0 from it on system initialization, functions
3 and 5 during suspend transitions and functions 4 and 6 during
resume transitions (to reverse the actions carried out by the
former). In particular, function 5 from the "Low-Power S0" device
_DSM is expected to cause the platform to put itself into a low-power
operation mode which should include making the EC less verbose (so to
speak). Next, on resume, function 6 switches the platform back to
the "working-state" operation mode.
In accordance with the above, modify the ACPI suspend-to-idle code
to look for the "Low-Power S0" _DSM interface on platforms with the
ACPI_FADT_LOW_POWER_S0 flag set in the ACPI tables. If it's there,
use it during suspend-to-idle transitions as prescribed and avoid
changing the GPE configuration in that case. [That should reflect
what the most recent versions of other OSes do.]
Also modify the ACPI EC driver to make it handle events during
suspend-to-idle in the usual way if the "Low-Power S0" _DSM interface
is going to be used to make the power button events work while
suspended on the Dell machines mentioned above
Link: http://www.uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI SCI (System Control Interrupt) is set up as a wakeup IRQ
during suspend-to-idle transitions and, consequently, any events
signaled through it wake up the system from that state. However,
on some systems some of the events signaled via the ACPI SCI while
suspended to idle should not cause the system to wake up. In fact,
quite often they should just be discarded.
Arguably, systems should not resume entirely on such events, but in
order to decide which events really should cause the system to resume
and which are spurious, it is necessary to resume up to the point
when ACPI SCIs are actually handled and processed, which is after
executing dpm_resume_noirq() in the system resume path.
For this reasons, add a loop around freeze_enter() in which the
platforms can process events signaled via multiplexed IRQ lines
like the ACPI SCI and add suspend-to-idle hooks that can be
used for this purpose to struct platform_freeze_ops.
In the ACPI case, the ->wake hook is used for checking if the SCI
has triggered while suspended and deferring the interrupt-induced
system wakeup until the events signaled through it are actually
processed sufficiently to decide whether or not the system should
resume. In turn, the ->sync hook allows all of the relevant event
queues to be flushed so as to prevent events from being missed due
to race conditions.
In addition to that, some ACPI code processing wakeup events needs
to be modified to use the "hard" version of wakeup triggers, so that
it will cause a system resume to happen on device-induced wakeup
events even if the "soft" mechanism to prevent the system from
suspending is not enabled. However, to preserve the existing
behavior with respect to suspend-to-RAM, this only is done in
the suspend-to-idle case and only if an SCI has occurred while
suspended.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The wakeup.flags.enabled flag in struct acpi_device is not used
consistently, as there is no reason why it should only apply
to the enabling/disabling of the wakeup GPE, so put the invocation
of acpi_enable_wakeup_device_power() under it too.
Moreover, it is not necessary to call
acpi_enable_wakeup_devices() and acpi_disable_wakeup_devices() for
suspend-to-idle, so don't do that.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert commit eed4d47efe (ACPI / sleep: Ignore spurious SCI wakeups
from suspend-to-idle) as it turned out to be premature and triggered
a number of different issues on various systems.
That includes, but is not limited to, premature suspend-to-RAM aborts
on Dell XPS 13 (9343) reported by Dominik.
The issue the commit in question attempted to address is real and
will need to be taken care of going forward, but evidently more work
is needed for this purpose.
Reported-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Update the ACPICA code in the kernel to upstream revision
20170303 which includes:
* Minor fixes and improvements in the core code (Bob Moore,
Seunghun Han).
* Debugger fixes (Colin Ian King, Lv Zheng).
* Compiler/disassembler improvements (Bob Moore, David Box,
Lv Zheng).
* Build-related update (Lv Zheng).
- Add new device IDs and platform-related information to the
ACPI drivers for Intel (LPSS) and AMD (APD) SoCs (Hanjun Guo,
Hans de Goede).
- Make it possible to quirk ACPI-enumerated devices as "always
present" on platforms where they are incorrectly reported as not
present by the AML and add the INT0002 device ID to the list of
"always present" devices (Hans de Goede).
- Fix the register information in the xpower PMIC driver and add
comments to map the registers to symbols used by AML to it
(Hans de Goede).
- Move the code turning off unused ACPI power resources during
system resume to a point after all devices have been resumed
to avoid issues with power resources that do not behave as
expected (Hans de Goede).
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Merge tag 'acpi-extra-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more ACPI updates from Rafael Wysocki:
"These update the ACPICA code in the kernel to upstream revision
20170303 which adds a few minor fixes and improvements, update ACPI
SoC drivers with new device IDs, platform-related information and
similar, fix the register information in the xpower PMIC driver,
introduce a concept of "always present" devices to the ACPI device
enumeration code and use it to fix a problem with one platform, and
fix a system resume issue related to power resources.
Specifics:
- Update the ACPICA code in the kernel to upstream revision 20170303
which includes:
* Minor fixes and improvements in the core code (Bob Moore,
Seunghun Han).
* Debugger fixes (Colin Ian King, Lv Zheng).
* Compiler/disassembler improvements (Bob Moore, David Box, Lv
Zheng).
* Build-related update (Lv Zheng).
- Add new device IDs and platform-related information to the ACPI
drivers for Intel (LPSS) and AMD (APD) SoCs (Hanjun Guo, Hans de
Goede).
- Make it possible to quirk ACPI-enumerated devices as "always
present" on platforms where they are incorrectly reported as not
present by the AML and add the INT0002 device ID to the list of
"always present" devices (Hans de Goede).
- Fix the register information in the xpower PMIC driver and add
comments to map the registers to symbols used by AML to it (Hans de
Goede).
- Move the code turning off unused ACPI power resources during system
resume to a point after all devices have been resumed to avoid
issues with power resources that do not behave as expected (Hans de
Goede)"
* tag 'acpi-extra-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (22 commits)
ACPI / power: Delay turning off unused power resources after suspend
ACPI / PMIC: xpower: Fix power_table addresses
ACPI / LPSS: Call pwm_add_table() for Bay Trail PWM device
ACPICA: Update version to 20170303
ACPICA: iasl: add ASL conversion tool
ACPICA: Local cache support: Allow small cache objects
ACPICA: Disassembler: Do not unconditionally remove temporary names
ACPICA: iasl: Fix IORT SMMU GSI disassembling
ACPICA: Cleanup AML opcode definitions, no functional change
ACPICA: Debugger: Add interpreter blocking mark for single-step mode
ACPICA: debugger: fix memory leak on Pathname
ACPICA: Update for automatic repair code for objects returned by evaluate_object
ACPICA: Namespace: fix operand cache leak
ACPICA: Fix several incorrect invocations of ACPICA return macro
ACPICA: Fix a module for excessive debug output
ACPICA: Update some function headers, no funtional change
ACPICA: Disassembler: Enhance resource descriptor detection
i2c: designware: Add ACPI HID for Hisilicon Hip07/08 I2C controller
ACPI / APD: Add clock frequency for Hisilicon Hip07/08 I2C controller
ACPI / bus: Add INT0002 to list of always-present devices
...
The ACPI SCI (System Control Interrupt) is set up as a wakeup IRQ
during suspend-to-idle transitions and, consequently, any events
signaled through it wake up the system from that state. However,
on some systems some of the events signaled via the ACPI SCI while
suspended to idle should not cause the system to wake up. In fact,
quite often they should just be discarded.
Arguably, systems should not resume entirely on such events, but in
order to decide which events really should cause the system to resume
and which are spurious, it is necessary to resume up to the point
when ACPI SCIs are actually handled and processed, which is after
executing dpm_resume_noirq() in the system resume path.
For this reasons, add a loop around freeze_enter() in which the
platforms can process events signaled via multiplexed IRQ lines
like the ACPI SCI and add suspend-to-idle hooks that can be
used for this purpose to struct platform_freeze_ops.
In the ACPI case, the ->wake hook is used for checking if the SCI
has triggered while suspended and deferring the interrupt-induced
system wakeup until the events signaled through it are actually
processed sufficiently to decide whether or not the system should
resume. In turn, the ->sync hook allows all of the relevant event
queues to be flushed so as to prevent events from being missed due
to race conditions.
In addition to that, some ACPI code processing wakeup events needs
to be modified to use the "hard" version of wakeup triggers, so that
it will cause a system resume to happen on device-induced wakeup
events even if the "soft" mechanism to prevent the system from
suspending is not enabled (that also helps to catch device-induced
wakeup events occurring during suspend transitions in progress).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 660b1113e0 (ACPI / PM: Fix consistency check for power resources
during resume) introduced a check for ACPI power resources which have
been turned on by the BIOS during suspend and turns these back off again.
This is causing problems on a Dell Venue Pro 11 7130 (i5-4300Y) it causes
the following messages to show up in dmesg:
[ 131.014605] ACPI: Waking up from system sleep state S3
[ 131.150271] acpi LNXPOWER:07: Turning OFF
[ 131.150323] acpi LNXPOWER:06: Turning OFF
[ 131.150911] acpi LNXPOWER:00: Turning OFF
[ 131.169014] ACPI : EC: interrupt unblocked
[ 131.181811] xhci_hcd 0000:00:14.0: System wakeup disabled by ACPI
[ 133.535728] pci_raw_set_power_state: 76 callbacks suppressed
[ 133.535735] iwlwifi 0000:01:00.0: Refused to change power state,
currently in D3
[ 133.597672] PM: noirq resume of devices complete after 2428.891 msecs
Followed by a bunch of iwlwifi errors later on and the pcie device
dropping from the bus (acpiphp thinks it has been unplugged).
Disabling the turning off of unused power resources fixes this. Instead
of adding a quirk for this system, this commit fixes this by moving the
disabling of unused power resources to later in the resume sequence
when the iwlwifi card has been moved out of D3 so the ref_count for
its power resource no longer is 0.
This new behavior seems to match the intend of the original commit which
commit-msg says: "(... which means that no devices are going to need them
any time soon) and we should turn them off".
This also avoids power resources which we need when bringing devices out
of D3 from getting bounced off and then back on again.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In commit 821d6f0359 (ACPI / sleep: Do not save NVS for new machines to
accelerate S3), to optimize S3 suspend/resume speed, code is introduced
to ignore NVS memory saving during S3 for all the platforms later than
2012.
But, Lenovo G50-45, a platform released in 2015, still needs NVS memory
saving during S3. A quirk is introduced for this platform.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=189431
Tested-by: Przemek <soprwa@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[ rjw: Drop unnecessary code ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert commit 08b98d3291 (PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0
flag) as it caused system suspend (in the default configuration) to fail
on Dell XPS13 (9360) with the Kaby Lake processor.
Fixes: 08b98d3291 (PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0 flag)
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Modify the ACPI system sleep support setup code to select
suspend-to-idle as the default system sleep state if the
ACPI_FADT_LOW_POWER_S0 flag is set in the FADT and the
default sleep state was not selected from the kernel command
line.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@dell.com>
Revert commit 2c85025c75 (ACPI: Execute _PTS before system reboot)
as it is reported to cause poweroff and reboot to hang on Dell
Latitude E7250.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=187061
Reported-by: Gianpaolo <gianpaoloc@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* acpi-wdat:
watchdog: wdat_wdt: Fix warning for using 0 as NULL
watchdog: wdat_wdt: fix return value check in wdat_wdt_probe()
platform/x86: intel_pmc_ipc: Do not create iTCO watchdog when WDAT table exists
i2c: i801: Do not create iTCO watchdog when WDAT table exists
mfd: lpc_ich: Do not create iTCO watchdog when WDAT table exists
ACPI / watchdog: Add support for WDAT hardware watchdog
* acpi-ec:
ACPI / EC: Fix issues related to boot_ec
ACPI / EC: Fix a gap that ECDT EC cannot handle EC events
ACPI / EC: Fix a memory leakage issue in acpi_ec_add()
ACPI / EC: Cleanup first_ec/boot_ec code
ACPI / EC: Enable event freeze mode to improve event handling for suspend process
ACPI / EC: Add PM operations to improve event handling for suspend process
ACPI / EC: Add PM operations to improve event handling for resume process
ACPI / EC: Fix an issue that SCI_EVT cannot be detected after event is enabled
ACPI / EC: Add EC_FLAGS_QUERY_ENABLED to reveal a hidden logic
ACPI / EC: Add PM operations for suspend/resume noirq stage
This patch makes 2 changes:
1. Restore old behavior
Originally, EC driver stops handling both events and transactions in
acpi_ec_block_transactions(), and restarts to handle transactions in
acpi_ec_unblock_transactions_early(), restarts to handle both events and
transactions in acpi_ec_unblock_transactions().
While currently, EC driver still stops handling both events and
transactions in acpi_ec_block_transactions(), but restarts to handle both
events and transactions in acpi_ec_unblock_transactions_early().
This patch tries to restore the old behavior by dropping
__acpi_ec_enable_event() from acpi_unblock_transactions_early().
2. Improve old behavior
However this still cannot fix the real issue as both of the
acpi_ec_unblock_xxx() functions are invoked in the noirq stage. Since the
EC driver actually doesn't implement the event handling in the polling
mode, re-enabling the event handling too early in the noirq stage could
result in the problem that if there is no triggering source causing
advance_transaction() to be invoked, pending SCI_EVT cannot be detected by
the EC driver and _Qxx cannot be triggered.
It actually makes sense to restart the event handling in any point during
resuming after the noirq stage. Just like the boot stage where the event
handling is enabled in .add(), this patch further moves
acpi_ec_enable_event() to .resume(). After doing that, the following 2
functions can be combined:
acpi_ec_unblock_transactions_early()/acpi_ec_unblock_transactions().
The differences of the event handling availability between the old behavior
(this patch isn't applied) and the new behavior (this patch is applied) are
as follows:
!Applied Applied
before suspend Y Y
suspend before EC Y Y
suspend after EC Y Y
suspend_late Y Y
suspend_noirq Y (actually N) Y (actually N)
resume_noirq Y (actually N) Y (actually N)
resume_late Y (actually N) Y (actually N)
resume before EC Y (actually N) Y (actually N)
resume after EC Y (actually N) Y
after resume Y (actually N) Y
Where "actually N" means if there is no triggering source, the EC driver
is actually not able to notice the pending SCI_EVT occurred in the noirq
stage. So we can clearly see that this patch has improved the situation.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Todd E Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Now GPE can be masked via the new acpi_mask_gpe() API and this patch
modifies /sys/firmware/acpi/interrupts/gpexx to use this new facility.
Writes "mask/unmask" to this file now invokes acpi_mask_gpe().
Reads from this file now returns new "EN/STS" when the corresponding GPE
hardware register's EN/STS bits are flagged, and new "masked/unmasked"
attribute to indicate the status of the masking mechanism.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The _PTS control method is defined in the section 7.4.1 of acpi 6.0
spec. The _PTS control method is executed by the OS during the sleep
transition process for S1, S2, S3, S4, and for orderly S5 shutdown.
The _PTS control method provides the BIOS a mechanism for performing
some housekeeping, such as writing the sleep type value to the embedded
controller, before entering the system sleeping state. Note that some
Lenovo Server BIOS use this mechanism to detect reboot event and
prompt user by popped dialog box.
According to section 7.5 of acpi 6.0 spec, _PTS should run after _TTS.
Add a _PTS evaulation to the existing _TTS reboot notifier and change
the notifier name to reflect the fact that it's not for _TTS only any
more.
Signed-off-by: Ocean He <hehy1@lenovo.com>
Signed-off-by: Nagananda Chumbalkar <nchumbalkar@lenovo.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The problem is Linux registers pm_power_off = efi_power_off only if
we are in hardware reduced mode. Actually, what we also want is to do
this when ACPI S5 is simply not supported on non-legacy platforms.
Since some future Intel platforms are HW-full mode where the DSDT
fails to supply an _S5 object(without SLP_TYP), we should let such
kind of platform to leverage efi runtime service to poweroff.
This patch uses efi power off as first choice when S5 is unavailable,
even if there is a customized poweroff(driver provided, eg).
Meanwhile, the legacy platforms will not be affected because there is
no path for them to overwrite the pm_power_off to efi power off.
Suggested-by: Len Brown <len.brown@intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 58a1fbbb2e ("PM / PCI / ACPI: Kick devices that might have been
reset by firmware") added a runtime resume for devices that were runtime
suspended when the system entered suspend-to-RAM.
Briefly, the motivation was to ensure that devices did not remain in a
reset-power-on state after resume, potentially preventing deep SoC-wide
low-power states from being entered on idle.
Currently we're not doing the same when leaving suspend-to-disk and this
asymmetry is a problem if drivers rely on the automatic resume triggered
by pm_complete_with_resume_check(). Fix it.
Fixes: 58a1fbbb2e (PM / PCI / ACPI: Kick devices that might have been reset by firmware)
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi_processor_sleep is neither related nor used by CPUIdle framework.
It's used in system suspend/resume path as a syscore operation. It makes
more sense to move it to acpi/sleep.c where all the S-state transition
(a.k.a. Linux system suspend/hiberate) related code are present.
Also make it depend on CONFIG_ACPI_SYSTEM_POWER_STATES_SUPPORT so that
it's not compiled on architecture like ARM64 where S-states are not
yet defined in ACPI.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit f06147f9fb (ACPICA: Hardware: Enable firmware waking vector
for both 32-bit and 64-bit FACS) added three functions that aren't
present in upstream ACPICA, acpi_hw_set_firmware_waking_vectors(),
acpi_set_firmware_waking_vectors() and acpi_set_firmware_waking_vector64(),
to allow Linux to use the previously existing API for setting the
platform firmware waking vector.
However, that wasn't necessary, since the ACPI sleep support code
in Linux can be modified to use the upstream ACPICA's API easily
and the additional functions may be dropped which reduces the code
size and puts the kernel's ACPICA code more in line with the upstream.
Make the changes as per the above. While at it, make the relevant
function desctiption comments reflect the upstream ACPICA's ones.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Lv Zheng <lv.zheng@intel.com>
* pm-sleep:
PM / hibernate: fix a comment typo
input: i8042: Avoid resetting controller on system suspend/resume
PM / PCI / ACPI: Kick devices that might have been reset by firmware
PM / sleep: Add flags to indicate platform firmware involvement
PM / sleep: Drop pm_request_idle() from pm_generic_complete()
PCI / PM: Avoid resuming more devices during system suspend
PM / wakeup: wakeup_source_create: use kstrdup_const
PM / sleep: Report interrupt that caused system wakeup
For an ACPI compatible system, the SCI (ACPI System Control
Interrupt) is used to wake the system up from suspend-to-idle.
Once the CPU is woken up by the SCI, the interrupt handler will
first check if the current IRQ has been configured for system
wakeup, so irq_pm_check_wakeup() is invoked to validate the IRQ
number. However, during suspend-to-idle, enable_irq_wake() is
called for acpi_gbl_FADT.sci_interrupt, although the IRQ number
that the SCI handler has been installed for should be passed to
it instead. Thus, if acpi_gbl_FADT.sci_interrupt happens to be
different from that number, ACPI interrupts will not be able to
wake up the system from sleep.
Fix this problem by passing the IRQ number returned by
acpi_gsi_to_irq() to enable_irq_wake() instead of
acpi_gbl_FADT.sci_interrupt.
Cc: 3.18+ <stable@vger.kernel.org> # 3.18+
Acked-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are quite a few cases in which device drivers, bus types or
even the PM core itself may benefit from knowing whether or not
the platform firmware will be involved in the upcoming system power
transition (during system suspend) or whether or not it was involved
in it (during system resume).
For this reason, introduce global system suspend flags that can be
used by the platform code to expose that information for the benefit
of the other parts of the kernel and make the ACPI core set them
as appropriate.
Users of the new flags will be added later.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently, in suspend-to-idle, wakeup GPE for PCI devices are
handled properly because acpi_pci_sleep_wake() invokes acpi_enable_gpe()
to enable the wakeup GPE directly. But for the other wakeup-capable
devices in ACPI bus, acpi_enable_wakeup_devices() should be invoked
to update enable_for_wake mask in gpe_register_info structure, thus
acpi_enable_all_wakeup_gpes() can enable the wakeup GPE referred in
_PRW methods. And acpi_disable_wakeup_devices() will be called
before disable_irq_wake() in acpi_freeze_restore() to restore the mask.
This patch fixes a power button wakeup problem on Surface Pro 3,
on which platform power button uses EC to deliver event
(EC GPE is referred in _PRW).
Note: enabling EC GPE during freeze state may bring some risks
because EC events are expected to fire more frequently than others.
Thus it may bring the system out of freeze state unnecessarily.
(We already have comments about this in bugzilla)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=84651
Reported-and-tested-by: Ethan Schoonover <es@ethanschoonover.com>
Tested-by: Peter Amidon <psa.pub.0@picnicpark.org>
Tested-by: Yani Ioadnnou <yani.ioannou@gmail.com>
Tested-by: Mister Wardrop <mister.wardrop@gmail.com>
Tested-by: Anton Anikin <anton@anikin.name>
Tested-by: Keith McClelland <zismylaptop@gmail.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The acpi_suspend() function has no callers, so drop it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
This makes a difference if the compiler decides not to inline the
function, as then the function's reference to acpisleep_dmi_table[]
yields a section mismatch warning.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After multiple GPEs have been disabled at the low level in one go,
like when acpi_disable_all_gpes() is called, we should always drain
all of the outstanding events from them, or interesting races become
possible.
For this reason, call acpi_os_wait_events_complete() after
acpi_enable_all_wakeup_gpes() and acpi_disable_all_gpes() in
acpi_freeze_prepare() and acpi_power_off_prepare(), respectively.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI GPE wakeup from suspend-to-idle is currently based on using
the IRQF_NO_SUSPEND flag for the ACPI SCI, but that is problematic
for a couple of reasons. First, in principle the ACPI SCI may be
shared and IRQF_NO_SUSPEND does not really work well with shared
interrupts. Second, it may require the ACPI subsystem to special-case
the handling of device notifications depending on whether or not
they are received during suspend-to-idle in some places which would
lead to fragile code. Finally, it's better the handle ACPI wakeup
interrupts consistently with wakeup interrupts from other sources.
For this reason, remove the IRQF_NO_SUSPEND flag from the ACPI SCI
and use enable_irq_wake()/disable_irq_wake() with it instead, which
requires two additional platform hooks to be added to struct
platform_freeze_ops.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
NVS region is saved and restored unconditionally for machines without
nvs_nosave quirk during S3. Tested some new machines and the operation
is not necessary. Saving NVS region also affects S2RAM speed. The time of
NVS saving and restoring depends on the size of NVS region and it consumes
7~10ms normally.
This patch is to make machines produced from 2012 to now not saving NVS region
to accelerate S3.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Adds trace events that give finer resolution into suspend/resume. These
events are graphed in the timelines generated by the analyze_suspend.py
script. They represent large areas of time consumed that are typical to
suspend and resume.
The event is triggered by calling the function "trace_suspend_resume"
with three arguments: a string (the name of the event to be displayed
in the timeline), an integer (case specific number, such as the power
state or cpu number), and a boolean (where true is used to denote the start
of the timeline event, and false to denote the end).
The suspend_resume trace event reproduces the data that the machine_suspend
trace event did, so the latter has been removed.
Signed-off-by: Todd Brandt <todd.e.brandt@intel.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The "freeze" sleep state suffers from the same issue that was
addressed by commit ad07277e82 (ACPI / PM: Hold acpi_scan_lock over
system PM transitions) for ACPI sleep states, that is, things break
if ->remove() is called for devices whose system resume callbacks
haven't been executed yet.
It also can be addressed in the same way, by holding the ACPI scan
lock over the "freeze" sleep state and PM transitions to and from
that state, but ->begin() and ->end() platform operations for the
"freeze" sleep state are needed for this purpose.
This change has been tested on Acer Aspire S5 with Thunderbolt.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Export the acpi_target_system_state() function to modules so that
modular drivers can use it to check what the target ACPI sleep state
of the system is (that is needed for i915 mostly at this point).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If the HW Reduced ACPI mode bit is set in the FADT, ACPICA uses
the optional sleep control and sleep status registers for making
the system enter sleep states (including S5), so it is not possible
to use system sleep states or power it off using ACPI if the HW
Reduced ACPI mode bit is set and those registers are not available.
For this reason, add a new function, acpi_sleep_state_supported(),
checking if the HW Reduced ACPI mode bit is set and whether or not
system sleep states are usable in that case in addition to checking
the return value of acpi_get_sleep_type_data() and make the ACPI
sleep setup routines use that function to check the availability of
system sleep states.
Among other things, this prevents the kernel from attempting to
use ACPI for powering off HW Reduced ACPI systems without the sleep
control and sleep status registers, because ACPI power off doesn't
have a chance to work on them. That allows alternative power off
mechanisms that may actually work to be used on those systems. The
affected machines include Dell Venue 8 Pro, Asus T100TA, Haswell
Desktop SDP and Ivy Bridge EP Demo depot.
References: https://bugzilla.kernel.org/show_bug.cgi?id=70931
Reported-by: Adam Williamson <awilliam@redhat.com>
Tested-by: Aubrey Li <aubrey.li@linux.intel.com>
Cc: 3.4+ <stable@vger.kernel.org> # 3.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert commit 3130497f5b ("ACPI / sleep: pm_power_off needs more
sanity checks to be installed") that breaks power ACPI power off on a
lot of systems, because it checks wrong registers.
Fixes: 3130497f5b ("ACPI / sleep: pm_power_off needs more sanity checks to be installed")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rafael J. Wysocki