linux/drivers/acpi/sleep.c

1271 lines
31 KiB

ACPI / power: Delay turning off unused power resources after suspend Commit 660b1113e0f3 (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>
2017-04-30 22:54:16 +02:00
ACPI / EC: Add PM operations to improve event handling for resume process 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>
2016-08-03 16:01:36 +08:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle 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>
2017-06-12 22:56:34 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle 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>
2017-06-12 22:56:34 +02:00
ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle 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>
2017-06-12 22:56:34 +02:00
ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle 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>
2017-06-12 22:56:34 +02:00
ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle 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>
2017-06-12 22:56:34 +02:00
ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle 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>
2017-06-12 22:56:34 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle 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>
2017-06-12 22:56:34 +02:00
ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems 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>
2017-06-23 15:24:32 +02:00
ACPI / EC: Add PM operations to improve event handling for resume process 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>
2016-08-03 16:01:36 +08:00
swsusp: introduce restore platform operations At least on some machines it is necessary to prepare the ACPI firmware for the restoration of the system memory state from the hibernation image if the "platform" mode of hibernation has been used. Namely, in that cases we need to disable the GPEs before replacing the "boot" kernel with the "frozen" kernel (cf. http://bugzilla.kernel.org/show_bug.cgi?id=7887). After the restore they will be re-enabled by hibernation_ops->finish(), but if the restore fails, they have to be re-enabled by the restore code explicitly. For this purpose we can introduce two additional hibernation operations, called pre_restore() and restore_cleanup() and call them from the restore code path. Still, they should be called if the "platform" mode of hibernation has been used, so we need to pass the information about the hibernation mode from the "frozen" kernel to the "boot" kernel in the image header. Apparently, we can't drop the disabling of GPEs before the restore because of Bug #7887 .  We also can't do it unconditionally, because the GPEs wouldn't have been enabled after a successful restore if the suspend had been done in the 'shutdown' or 'reboot' mode. In principle we could (and probably should) unconditionally disable the GPEs before each snapshot creation *and* before the restore, but then we'd have to unconditionally enable them after the snapshot creation as well as after the restore (or restore failure)   Still, for this purpose we'd need to modify acpi_enter_sleep_state_prep() and acpi_leave_sleep_state() and we'd have to introduce some mechanism synchronizing the disablind/enabling of the GPEs with the device drivers' .suspend()/.resume() routines and with disable_/enable_nonboot_cpus().  However, this would have affected the suspend (ie. s2ram) code as well as the hibernation, which I'd like to avoid in this patch series. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Nigel Cunningham <nigel@nigel.suspend2.net> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 01:47:30 -07:00