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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-14 13:12:24 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-14 13:12:24 -0700 |
commit | b018fc9800557bd14a40d69501e19c340eb2c521 (patch) | |
tree | 541109645e83725699d2b091a1c6c4816fdc6649 /Documentation | |
parent | c07b3682cd12a017f976ec63bbd4758dc4c5100e (diff) | |
parent | 7425ecd5e3e8c9d84f399a102282a23a90a19278 (diff) | |
download | talos-obmc-linux-b018fc9800557bd14a40d69501e19c340eb2c521.tar.gz talos-obmc-linux-b018fc9800557bd14a40d69501e19c340eb2c521.zip |
Merge tag 'pm-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These add a new framework for CPU idle time injection, to be used by
all of the idle injection code in the kernel in the future, fix some
issues and add a number of relatively small extensions in multiple
places.
Specifics:
- Add a new framework for CPU idle time injection (Daniel Lezcano).
- Add AVS support to the armada-37xx cpufreq driver (Gregory
CLEMENT).
- Add support for current CPU frequency reporting to the ACPI CPPC
cpufreq driver (George Cherian).
- Rework the cooling device registration in the imx6q/thermal driver
(Bastian Stender).
- Make the pcc-cpufreq driver refuse to work with dynamic scaling
governors on systems with many CPUs to avoid scalability issues
with it (Rafael Wysocki).
- Fix the intel_pstate driver to report different maximum CPU
frequencies on systems where they really are different and to
ignore the turbo active ratio if hardware-managend P-states (HWP)
are in use; make it use the match_string() helper (Xie Yisheng,
Srinivas Pandruvada).
- Fix a minor deferred probe issue in the qcom-kryo cpufreq driver
(Niklas Cassel).
- Add a tracepoint for the tracking of frequency limits changes (from
Andriod) to the cpufreq core (Ruchi Kandoi).
- Fix a circular lock dependency between CPU hotplug and sysfs
locking in the cpufreq core reported by lockdep (Waiman Long).
- Avoid excessive error reports on driver registration failures in
the ARM cpuidle driver (Sudeep Holla).
- Add a new device links flag to the driver core to make links go
away automatically on supplier driver removal (Vivek Gautam).
- Eliminate potential race condition between system-wide power
management transitions and system shutdown (Pingfan Liu).
- Add a quirk to save NVS memory on system suspend for the ASUS 1025C
laptop (Willy Tarreau).
- Make more systems use suspend-to-idle (instead of ACPI S3) by
default (Tristian Celestin).
- Get rid of stack VLA usage in the low-level hibernation code on
64-bit x86 (Kees Cook).
- Fix error handling in the hibernation core and mark an expected
fall-through switch in it (Chengguang Xu, Gustavo Silva).
- Extend the generic power domains (genpd) framework to support
attaching a device to a power domain by name (Ulf Hansson).
- Fix device reference counting and user limits initialization in the
devfreq core (Arvind Yadav, Matthias Kaehlcke).
- Fix a few issues in the rk3399_dmc devfreq driver and improve its
documentation (Enric Balletbo i Serra, Lin Huang, Nick Milner).
- Drop a redundant error message from the exynos-ppmu devfreq driver
(Markus Elfring)"
* tag 'pm-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (35 commits)
PM / reboot: Eliminate race between reboot and suspend
PM / hibernate: Mark expected switch fall-through
cpufreq: intel_pstate: Ignore turbo active ratio in HWP
cpufreq: Fix a circular lock dependency problem
cpu/hotplug: Add a cpus_read_trylock() function
x86/power/hibernate_64: Remove VLA usage
cpufreq: trace frequency limits change
cpufreq: intel_pstate: Show different max frequency with turbo 3 and HWP
cpufreq: pcc-cpufreq: Disable dynamic scaling on many-CPU systems
cpufreq: qcom-kryo: Silently error out on EPROBE_DEFER
cpufreq / CPPC: Add cpuinfo_cur_freq support for CPPC
cpufreq: armada-37xx: Add AVS support
dt-bindings: marvell: Add documentation for the Armada 3700 AVS binding
PM / devfreq: rk3399_dmc: Fix duplicated opp table on reload.
PM / devfreq: Init user limits from OPP limits, not viceversa
PM / devfreq: rk3399_dmc: fix spelling mistakes.
PM / devfreq: rk3399_dmc: do not print error when get supply and clk defer.
dt-bindings: devfreq: rk3399_dmc: move interrupts to be optional.
PM / devfreq: rk3399_dmc: remove wait for dcf irq event.
dt-bindings: clock: add rk3399 DDR3 standard speed bins.
...
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt | 15 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt | 211 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/power/power_domain.txt | 8 | ||||
-rw-r--r-- | Documentation/driver-api/device_link.rst | 12 | ||||
-rw-r--r-- | Documentation/power/freezing-of-tasks.txt | 12 | ||||
-rw-r--r-- | Documentation/power/suspend-and-cpuhotplug.txt | 6 | ||||
-rw-r--r-- | Documentation/trace/events-power.rst | 1 |
7 files changed, 149 insertions, 116 deletions
diff --git a/Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt b/Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt index 35c3c3460d17..eddde4faef01 100644 --- a/Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt +++ b/Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt @@ -33,3 +33,18 @@ nb_pm: syscon@14000 { compatible = "marvell,armada-3700-nb-pm", "syscon"; reg = <0x14000 0x60>; } + +AVS +--- + +For AVS an other component is needed: + +Required properties: +- compatible : should contain "marvell,armada-3700-avs", "syscon"; +- reg : the register start and length for the AVS + +Example: +avs: avs@11500 { + compatible = "marvell,armada-3700-avs", "syscon"; + reg = <0x11500 0x40>; +} diff --git a/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt index fc2bcbe26b1e..0ec68141f85a 100644 --- a/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt +++ b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt @@ -1,14 +1,10 @@ -* Rockchip rk3399 DMC(Dynamic Memory Controller) device +* Rockchip rk3399 DMC (Dynamic Memory Controller) device Required properties: - compatible: Must be "rockchip,rk3399-dmc". - devfreq-events: Node to get DDR loading, Refer to - Documentation/devicetree/bindings/devfreq/ + Documentation/devicetree/bindings/devfreq/event/ rockchip-dfi.txt -- interrupts: The interrupt number to the CPU. The interrupt - specifier format depends on the interrupt controller. - It should be DCF interrupts, when DDR dvfs finish, - it will happen. - clocks: Phandles for clock specified in "clock-names" property - clock-names : The name of clock used by the DFI, must be "pclk_ddr_mon"; @@ -17,139 +13,148 @@ Required properties: - center-supply: DMC supply node. - status: Marks the node enabled/disabled. -Following properties are ddr timing: - -- rockchip,dram_speed_bin : Value reference include/dt-bindings/clock/ddr.h, - it select ddr3 cl-trp-trcd type, default value - "DDR3_DEFAULT".it must selected according to - "Speed Bin" in ddr3 datasheet, DO NOT use - smaller "Speed Bin" than ddr3 exactly is. - -- rockchip,pd_idle : Config the PD_IDLE value, defined the power-down - idle period, memories are places into power-down - mode if bus is idle for PD_IDLE DFI clocks. - -- rockchip,sr_idle : Configure the SR_IDLE value, defined the - selfrefresh idle period, memories are places - into self-refresh mode if bus is idle for - SR_IDLE*1024 DFI clocks (DFI clocks freq is - half of dram's clocks), defaule value is "0". - -- rockchip,sr_mc_gate_idle : Defined the self-refresh with memory and - controller clock gating idle period, memories - are places into self-refresh mode and memory - controller clock arg gating if bus is idle for - sr_mc_gate_idle*1024 DFI clocks. - -- rockchip,srpd_lite_idle : Defined the self-refresh power down idle - period, memories are places into self-refresh - power down mode if bus is idle for - srpd_lite_idle*1024 DFI clocks. This parameter - is for LPDDR4 only. - -- rockchip,standby_idle : Defined the standby idle period, memories are - places into self-refresh than controller, pi, - phy and dram clock will gating if bus is idle - for standby_idle * DFI clocks. - -- rockchip,dram_dll_disb_freq : It's defined the DDR3 dll bypass frequency in - MHz, when ddr freq less than DRAM_DLL_DISB_FREQ, - ddr3 dll will bypssed note: if dll was bypassed, - the odt also stop working. - -- rockchip,phy_dll_disb_freq : Defined the PHY dll bypass frequency in - MHz (Mega Hz), when ddr freq less than - DRAM_DLL_DISB_FREQ, phy dll will bypssed. - note: phy dll and phy odt are independent. - -- rockchip,ddr3_odt_disb_freq : When dram type is DDR3, this parameter defined - the odt disable frequency in MHz (Mega Hz), - when ddr frequency less then ddr3_odt_disb_freq, - the odt on dram side and controller side are +Optional properties: +- interrupts: The CPU interrupt number. The interrupt specifier + format depends on the interrupt controller. + It should be a DCF interrupt. When DDR DVFS finishes + a DCF interrupt is triggered. + +Following properties relate to DDR timing: + +- rockchip,dram_speed_bin : Value reference include/dt-bindings/clock/rk3399-ddr.h, + it selects the DDR3 cl-trp-trcd type. It must be + set according to "Speed Bin" in DDR3 datasheet, + DO NOT use a smaller "Speed Bin" than specified + for the DDR3 being used. + +- rockchip,pd_idle : Configure the PD_IDLE value. Defines the + power-down idle period in which memories are + placed into power-down mode if bus is idle + for PD_IDLE DFI clock cycles. + +- rockchip,sr_idle : Configure the SR_IDLE value. Defines the + self-refresh idle period in which memories are + placed into self-refresh mode if bus is idle + for SR_IDLE * 1024 DFI clock cycles (DFI + clocks freq is half of DRAM clock), default + value is "0". + +- rockchip,sr_mc_gate_idle : Defines the memory self-refresh and controller + clock gating idle period. Memories are placed + into self-refresh mode and memory controller + clock arg gating started if bus is idle for + sr_mc_gate_idle*1024 DFI clock cycles. + +- rockchip,srpd_lite_idle : Defines the self-refresh power down idle + period in which memories are placed into + self-refresh power down mode if bus is idle + for srpd_lite_idle * 1024 DFI clock cycles. + This parameter is for LPDDR4 only. + +- rockchip,standby_idle : Defines the standby idle period in which + memories are placed into self-refresh mode. + The controller, pi, PHY and DRAM clock will + be gated if bus is idle for standby_idle * DFI + clock cycles. + +- rockchip,dram_dll_dis_freq : Defines the DDR3 DLL bypass frequency in MHz. + When DDR frequency is less than DRAM_DLL_DISB_FREQ, + DDR3 DLL will be bypassed. Note: if DLL was bypassed, + the odt will also stop working. + +- rockchip,phy_dll_dis_freq : Defines the PHY dll bypass frequency in + MHz (Mega Hz). When DDR frequency is less than + DRAM_DLL_DISB_FREQ, PHY DLL will be bypassed. + Note: PHY DLL and PHY ODT are independent. + +- rockchip,ddr3_odt_dis_freq : When the DRAM type is DDR3, this parameter defines + the ODT disable frequency in MHz (Mega Hz). + when the DDR frequency is less then ddr3_odt_dis_freq, + the ODT on the DRAM side and controller side are both disabled. -- rockchip,ddr3_drv : When dram type is DDR3, this parameter define - the dram side driver stength in ohm, default +- rockchip,ddr3_drv : When the DRAM type is DDR3, this parameter defines + the DRAM side driver strength in ohms. Default value is DDR3_DS_40ohm. -- rockchip,ddr3_odt : When dram type is DDR3, this parameter define - the dram side ODT stength in ohm, default value +- rockchip,ddr3_odt : When the DRAM type is DDR3, this parameter defines + the DRAM side ODT strength in ohms. Default value is DDR3_ODT_120ohm. -- rockchip,phy_ddr3_ca_drv : When dram type is DDR3, this parameter define - the phy side CA line(incluing command line, +- rockchip,phy_ddr3_ca_drv : When the DRAM type is DDR3, this parameter defines + the phy side CA line (incluing command line, address line and clock line) driver strength. Default value is PHY_DRV_ODT_40. -- rockchip,phy_ddr3_dq_drv : When dram type is DDR3, this parameter define - the phy side DQ line(incluing DQS/DQ/DM line) - driver strength. default value is PHY_DRV_ODT_40. +- rockchip,phy_ddr3_dq_drv : When the DRAM type is DDR3, this parameter defines + the PHY side DQ line (including DQS/DQ/DM line) + driver strength. Default value is PHY_DRV_ODT_40. -- rockchip,phy_ddr3_odt : When dram type is DDR3, this parameter define the - phy side odt strength, default value is +- rockchip,phy_ddr3_odt : When the DRAM type is DDR3, this parameter defines + the PHY side ODT strength. Default value is PHY_DRV_ODT_240. -- rockchip,lpddr3_odt_disb_freq : When dram type is LPDDR3, this parameter defined - then odt disable frequency in MHz (Mega Hz), - when ddr frequency less then ddr3_odt_disb_freq, - the odt on dram side and controller side are +- rockchip,lpddr3_odt_dis_freq : When the DRAM type is LPDDR3, this parameter defines + then ODT disable frequency in MHz (Mega Hz). + When DDR frequency is less then ddr3_odt_dis_freq, + the ODT on the DRAM side and controller side are both disabled. -- rockchip,lpddr3_drv : When dram type is LPDDR3, this parameter define - the dram side driver stength in ohm, default +- rockchip,lpddr3_drv : When the DRAM type is LPDDR3, this parameter defines + the DRAM side driver strength in ohms. Default value is LP3_DS_34ohm. -- rockchip,lpddr3_odt : When dram type is LPDDR3, this parameter define - the dram side ODT stength in ohm, default value +- rockchip,lpddr3_odt : When the DRAM type is LPDDR3, this parameter defines + the DRAM side ODT strength in ohms. Default value is LP3_ODT_240ohm. -- rockchip,phy_lpddr3_ca_drv : When dram type is LPDDR3, this parameter define - the phy side CA line(incluing command line, +- rockchip,phy_lpddr3_ca_drv : When the DRAM type is LPDDR3, this parameter defines + the PHY side CA line (including command line, address line and clock line) driver strength. - default value is PHY_DRV_ODT_40. + Default value is PHY_DRV_ODT_40. -- rockchip,phy_lpddr3_dq_drv : When dram type is LPDDR3, this parameter define - the phy side DQ line(incluing DQS/DQ/DM line) - driver strength. default value is +- rockchip,phy_lpddr3_dq_drv : When the DRAM type is LPDDR3, this parameter defines + the PHY side DQ line (including DQS/DQ/DM line) + driver strength. Default value is PHY_DRV_ODT_40. - rockchip,phy_lpddr3_odt : When dram type is LPDDR3, this parameter define the phy side odt strength, default value is PHY_DRV_ODT_240. -- rockchip,lpddr4_odt_disb_freq : When dram type is LPDDR4, this parameter - defined the odt disable frequency in - MHz (Mega Hz), when ddr frequency less then - ddr3_odt_disb_freq, the odt on dram side and +- rockchip,lpddr4_odt_dis_freq : When the DRAM type is LPDDR4, this parameter + defines the ODT disable frequency in + MHz (Mega Hz). When the DDR frequency is less then + ddr3_odt_dis_freq, the ODT on the DRAM side and controller side are both disabled. -- rockchip,lpddr4_drv : When dram type is LPDDR4, this parameter define - the dram side driver stength in ohm, default +- rockchip,lpddr4_drv : When the DRAM type is LPDDR4, this parameter defines + the DRAM side driver strength in ohms. Default value is LP4_PDDS_60ohm. -- rockchip,lpddr4_dq_odt : When dram type is LPDDR4, this parameter define - the dram side ODT on dqs/dq line stength in ohm, - default value is LP4_DQ_ODT_40ohm. +- rockchip,lpddr4_dq_odt : When the DRAM type is LPDDR4, this parameter defines + the DRAM side ODT on DQS/DQ line strength in ohms. + Default value is LP4_DQ_ODT_40ohm. -- rockchip,lpddr4_ca_odt : When dram type is LPDDR4, this parameter define - the dram side ODT on ca line stength in ohm, - default value is LP4_CA_ODT_40ohm. +- rockchip,lpddr4_ca_odt : When the DRAM type is LPDDR4, this parameter defines + the DRAM side ODT on CA line strength in ohms. + Default value is LP4_CA_ODT_40ohm. -- rockchip,phy_lpddr4_ca_drv : When dram type is LPDDR4, this parameter define - the phy side CA line(incluing command address - line) driver strength. default value is +- rockchip,phy_lpddr4_ca_drv : When the DRAM type is LPDDR4, this parameter defines + the PHY side CA line (including command address + line) driver strength. Default value is PHY_DRV_ODT_40. -- rockchip,phy_lpddr4_ck_cs_drv : When dram type is LPDDR4, this parameter define - the phy side clock line and cs line driver - strength. default value is PHY_DRV_ODT_80. +- rockchip,phy_lpddr4_ck_cs_drv : When the DRAM type is LPDDR4, this parameter defines + the PHY side clock line and CS line driver + strength. Default value is PHY_DRV_ODT_80. -- rockchip,phy_lpddr4_dq_drv : When dram type is LPDDR4, this parameter define - the phy side DQ line(incluing DQS/DQ/DM line) - driver strength. default value is PHY_DRV_ODT_80. +- rockchip,phy_lpddr4_dq_drv : When the DRAM type is LPDDR4, this parameter defines + the PHY side DQ line (including DQS/DQ/DM line) + driver strength. Default value is PHY_DRV_ODT_80. -- rockchip,phy_lpddr4_odt : When dram type is LPDDR4, this parameter define - the phy side odt strength, default value is +- rockchip,phy_lpddr4_odt : When the DRAM type is LPDDR4, this parameter defines + the PHY side ODT strength. Default value is PHY_DRV_ODT_60. Example: diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt index 7dec508987c7..8f8b25a24b8f 100644 --- a/Documentation/devicetree/bindings/power/power_domain.txt +++ b/Documentation/devicetree/bindings/power/power_domain.txt @@ -114,18 +114,26 @@ Required properties: - power-domains : A list of PM domain specifiers, as defined by bindings of the power controller that is the PM domain provider. +Optional properties: + - power-domain-names : A list of power domain name strings sorted in the same + order as the power-domains property. Consumers drivers will use + power-domain-names to match power domains with power-domains + specifiers. + Example: leaky-device@12350000 { compatible = "foo,i-leak-current"; reg = <0x12350000 0x1000>; power-domains = <&power 0>; + power-domain-names = "io"; }; leaky-device@12351000 { compatible = "foo,i-leak-current"; reg = <0x12351000 0x1000>; power-domains = <&power 0>, <&power 1> ; + power-domain-names = "io", "clk"; }; The first example above defines a typical PM domain consumer device, which is diff --git a/Documentation/driver-api/device_link.rst b/Documentation/driver-api/device_link.rst index 70e328e16aad..d6763272e747 100644 --- a/Documentation/driver-api/device_link.rst +++ b/Documentation/driver-api/device_link.rst @@ -81,10 +81,14 @@ integration is desired. Two other flags are specifically targeted at use cases where the device link is added from the consumer's ``->probe`` callback: ``DL_FLAG_RPM_ACTIVE`` can be specified to runtime resume the supplier upon addition of the -device link. ``DL_FLAG_AUTOREMOVE`` causes the device link to be automatically -purged when the consumer fails to probe or later unbinds. This obviates -the need to explicitly delete the link in the ``->remove`` callback or in -the error path of the ``->probe`` callback. +device link. ``DL_FLAG_AUTOREMOVE_CONSUMER`` causes the device link to be +automatically purged when the consumer fails to probe or later unbinds. +This obviates the need to explicitly delete the link in the ``->remove`` +callback or in the error path of the ``->probe`` callback. + +Similarly, when the device link is added from supplier's ``->probe`` callback, +``DL_FLAG_AUTOREMOVE_SUPPLIER`` causes the device link to be automatically +purged when the supplier fails to probe or later unbinds. Limitations =========== diff --git a/Documentation/power/freezing-of-tasks.txt b/Documentation/power/freezing-of-tasks.txt index af005770e767..cd283190855a 100644 --- a/Documentation/power/freezing-of-tasks.txt +++ b/Documentation/power/freezing-of-tasks.txt @@ -204,26 +204,26 @@ VI. Are there any precautions to be taken to prevent freezing failures? Yes, there are. -First of all, grabbing the 'pm_mutex' lock to mutually exclude a piece of code +First of all, grabbing the 'system_transition_mutex' lock to mutually exclude a piece of code from system-wide sleep such as suspend/hibernation is not encouraged. If possible, that piece of code must instead hook onto the suspend/hibernation notifiers to achieve mutual exclusion. Look at the CPU-Hotplug code (kernel/cpu.c) for an example. -However, if that is not feasible, and grabbing 'pm_mutex' is deemed necessary, -it is strongly discouraged to directly call mutex_[un]lock(&pm_mutex) since +However, if that is not feasible, and grabbing 'system_transition_mutex' is deemed necessary, +it is strongly discouraged to directly call mutex_[un]lock(&system_transition_mutex) since that could lead to freezing failures, because if the suspend/hibernate code -successfully acquired the 'pm_mutex' lock, and hence that other entity failed +successfully acquired the 'system_transition_mutex' lock, and hence that other entity failed to acquire the lock, then that task would get blocked in TASK_UNINTERRUPTIBLE state. As a consequence, the freezer would not be able to freeze that task, leading to freezing failure. However, the [un]lock_system_sleep() APIs are safe to use in this scenario, since they ask the freezer to skip freezing this task, since it is anyway -"frozen enough" as it is blocked on 'pm_mutex', which will be released +"frozen enough" as it is blocked on 'system_transition_mutex', which will be released only after the entire suspend/hibernation sequence is complete. So, to summarize, use [un]lock_system_sleep() instead of directly using -mutex_[un]lock(&pm_mutex). That would prevent freezing failures. +mutex_[un]lock(&system_transition_mutex). That would prevent freezing failures. V. Miscellaneous /sys/power/pm_freeze_timeout controls how long it will cost at most to freeze diff --git a/Documentation/power/suspend-and-cpuhotplug.txt b/Documentation/power/suspend-and-cpuhotplug.txt index 6f55eb960a6d..a8751b8df10e 100644 --- a/Documentation/power/suspend-and-cpuhotplug.txt +++ b/Documentation/power/suspend-and-cpuhotplug.txt @@ -32,7 +32,7 @@ More details follow: sysfs file | v - Acquire pm_mutex lock + Acquire system_transition_mutex lock | v Send PM_SUSPEND_PREPARE @@ -96,10 +96,10 @@ execution during resume): * thaw tasks * send PM_POST_SUSPEND notifications -* Release pm_mutex lock. +* Release system_transition_mutex lock. -It is to be noted here that the pm_mutex lock is acquired at the very +It is to be noted here that the system_transition_mutex lock is acquired at the very beginning, when we are just starting out to suspend, and then released only after the entire cycle is complete (i.e., suspend + resume). diff --git a/Documentation/trace/events-power.rst b/Documentation/trace/events-power.rst index a77daca75e30..2ef318962e29 100644 --- a/Documentation/trace/events-power.rst +++ b/Documentation/trace/events-power.rst @@ -27,6 +27,7 @@ cpufreq. cpu_idle "state=%lu cpu_id=%lu" cpu_frequency "state=%lu cpu_id=%lu" + cpu_frequency_limits "min=%lu max=%lu cpu_id=%lu" A suspend event is used to indicate the system going in and out of the suspend mode: |