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2014-01-24Merge tag 'pm+acpi-3.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: "As far as the number of commits goes, the top spot belongs to ACPI this time with cpufreq in the second position and a handful of PM core, PNP and cpuidle updates. They are fixes and cleanups mostly, as usual, with a couple of new features in the mix. The most visible change is probably that we will create struct acpi_device objects (visible in sysfs) for all devices represented in the ACPI tables regardless of their status and there will be a new sysfs attribute under those objects allowing user space to check that status via _STA. Consequently, ACPI device eject or generally hot-removal will not delete those objects, unless the table containing the corresponding namespace nodes is unloaded, which is extremely rare. Also ACPI container hotplug will be handled quite a bit differently and cpufreq will support CPU boost ("turbo") generically and not only in the acpi-cpufreq driver. Specifics: - ACPI core changes to make it create a struct acpi_device object for every device represented in the ACPI tables during all namespace scans regardless of the current status of that device. In accordance with this, ACPI hotplug operations will not delete those objects, unless the underlying ACPI tables go away. - On top of the above, new sysfs attribute for ACPI device objects allowing user space to check device status by triggering the execution of _STA for its ACPI object. From Srinivas Pandruvada. - ACPI core hotplug changes reducing code duplication, integrating the PCI root hotplug with the core and reworking container hotplug. - ACPI core simplifications making it use ACPI_COMPANION() in the code "glueing" ACPI device objects to "physical" devices. - ACPICA update to upstream version 20131218. This adds support for the DBG2 and PCCT tables to ACPICA, fixes some bugs and improves debug facilities. From Bob Moore, Lv Zheng and Betty Dall. - Init code change to carry out the early ACPI initialization earlier. That should allow us to use ACPI during the timekeeping initialization and possibly to simplify the EFI initialization too. From Chun-Yi Lee. - Clenups of the inclusions of ACPI headers in many places all over from Lv Zheng and Rashika Kheria (work in progress). - New helper for ACPI _DSM execution and rework of the code in drivers that uses _DSM to execute it via the new helper. From Jiang Liu. - New Win8 OSI blacklist entries from Takashi Iwai. - Assorted ACPI fixes and cleanups from Al Stone, Emil Goode, Hanjun Guo, Lan Tianyu, Masanari Iida, Oliver Neukum, Prarit Bhargava, Rashika Kheria, Tang Chen, Zhang Rui. - intel_pstate driver updates, including proper Baytrail support, from Dirk Brandewie and intel_pstate documentation from Ramkumar Ramachandra. - Generic CPU boost ("turbo") support for cpufreq from Lukasz Majewski. - powernow-k6 cpufreq driver fixes from Mikulas Patocka. - cpufreq core fixes and cleanups from Viresh Kumar, Jane Li, Mark Brown. - Assorted cpufreq drivers fixes and cleanups from Anson Huang, John Tobias, Paul Bolle, Paul Walmsley, Sachin Kamat, Shawn Guo, Viresh Kumar. - cpuidle cleanups from Bartlomiej Zolnierkiewicz. - Support for hibernation APM events from Bin Shi. - Hibernation fix to avoid bringing up nonboot CPUs with ACPI EC disabled during thaw transitions from Bjørn Mork. - PM core fixes and cleanups from Ben Dooks, Leonardo Potenza, Ulf Hansson. - PNP subsystem fixes and cleanups from Dmitry Torokhov, Levente Kurusa, Rashika Kheria. - New tool for profiling system suspend from Todd E Brandt and a cpupower tool cleanup from One Thousand Gnomes" * tag 'pm+acpi-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (153 commits) thermal: exynos: boost: Automatic enable/disable of BOOST feature (at Exynos4412) cpufreq: exynos4x12: Change L0 driver data to CPUFREQ_BOOST_FREQ Documentation: cpufreq / boost: Update BOOST documentation cpufreq: exynos: Extend Exynos cpufreq driver to support boost cpufreq / boost: Kconfig: Support for software-managed BOOST acpi-cpufreq: Adjust the code to use the common boost attribute cpufreq: Add boost frequency support in core intel_pstate: Add trace point to report internal state. cpufreq: introduce cpufreq_generic_get() routine ARM: SA1100: Create dummy clk_get_rate() to avoid build failures cpufreq: stats: create sysfs entries when cpufreq_stats is a module cpufreq: stats: free table and remove sysfs entry in a single routine cpufreq: stats: remove hotplug notifiers cpufreq: stats: handle cpufreq_unregister_driver() and suspend/resume properly cpufreq: speedstep: remove unused speedstep_get_state platform: introduce OF style 'modalias' support for platform bus PM / tools: new tool for suspend/resume performance optimization ACPI: fix module autoloading for ACPI enumerated devices ACPI: add module autoloading support for ACPI enumerated devices ACPI: fix create_modalias() return value handling ...
2014-01-17Merge branch 'pm-cpuidle'Rafael J. Wysocki
* pm-cpuidle: intel_idle: remove superfluous dev->state_count initialization intel_idle: do C1E promotion disable quirk for hotplugged CPUs ACPI / cpuidle: remove dev->state_count setting ACPI / cpuidle: fix max idle state handling with hotplug CPU support POWERPC: pseries: cpuidle: use the common cpuidle_[un]register() routines POWERPC: pseries: cpuidle: remove superfluous dev->state_count initialization ARM: EXYNOS: cpuidle: fix AFTR mode check
2014-01-11ACPI / cpuidle: remove dev->state_count settingBartlomiej Zolnierkiewicz
dev->state_count is now always equal to drv->state_count and drv->state_count no longer can change during driver's lifetime so the default dev->state_count initialization in cpuidle_enable_device() (called from cpuidle_register_device()) can be used instead. Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-11ACPI / cpuidle: fix max idle state handling with hotplug CPU supportBartlomiej Zolnierkiewicz
acpi_processor_hotplug() calls acpi_processor_setup_cpuidle_cx() without calling acpi_processor_setup_cpuidle_states() first so it is possible that dev->state_count becomes different from drv->state_count (in case of SMP system with unsupported C2/C3 states + enabled CPU hotplug and num_online_cpus() becoming > 1). The driver code assumes that cpuidle core will handle such cases but currently this is untrue (dev->state_count is used only for handling cpuidle state sysfs entries and drv->state_count is used for all other cases) and will not be fixed in the future as dev->state_count is planned to be removed. Fix the issue by checking for the max supported idle state in C2/C3 state's ->enter handler (acpi_idle_enter_simple() for C2/C3 and acpi_idle_enter_bm() for C3 + bm_check flag set) and setting the C1 state (instead of higher states) when needed. Also remove no longer needed max idle state checks from acpi_processor_setup_cpuidle_[states,cx](). Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-19x86, acpi, idle: Restructure the mwait idle routinesPeter Zijlstra
People seem to delight in writing wrong and broken mwait idle routines; collapse the lot. This leaves mwait_play_dead() the sole remaining user of __mwait() and new __mwait() users are probably doing it wrong. Also remove __sti_mwait() as its unused. Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Jacob Jun Pan <jacob.jun.pan@linux.intel.com> Cc: Mike Galbraith <bitbucket@online.de> Cc: Len Brown <lenb@kernel.org> Cc: Rui Zhang <rui.zhang@intel.com> Acked-by: Rafael Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131212141654.616820819@infradead.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-12-19ACPI / processor: initialize a variable to silence compiler warningAl Stone
In acpi_processor_resume(), the variable resumed_bm_rld is being used without being initialized, so initialize it. Signed-off-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-07ACPI: remove trailing whitespaceAl Stone
Minor cleanup: remove some extra trailing white space. Signed-off-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-07ACPI: Clean up inclusions of ACPI header filesLv Zheng
Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h> inclusions and remove some inclusions of those files that aren't necessary. First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h> should not be included directly from any files that are built for CONFIG_ACPI unset, because that generally leads to build warnings about undefined symbols in !CONFIG_ACPI builds. For CONFIG_ACPI set, <linux/acpi.h> includes those files and for CONFIG_ACPI unset it provides stub ACPI symbols to be used in that case. Second, there are ordering dependencies between those files that always have to be met. Namely, it is required that <acpi/acpi_bus.h> be included prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the latter depends on are always there. And <acpi/acpi.h> which provides basic ACPICA type declarations should always be included prior to any other ACPI headers in CONFIG_ACPI builds. That also is taken care of including <linux/acpi.h> as appropriate. Signed-off-by: Lv Zheng <lv.zheng@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Tony Luck <tony.luck@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff) Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-14Merge tag 'pm+acpi-3.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael J Wysocki: - New power capping framework and the the Intel Running Average Power Limit (RAPL) driver using it from Srinivas Pandruvada and Jacob Pan. - Addition of the in-kernel switching feature to the arm_big_little cpufreq driver from Viresh Kumar and Nicolas Pitre. - cpufreq support for iMac G5 from Aaro Koskinen. - Baytrail processors support for intel_pstate from Dirk Brandewie. - cpufreq support for Midway/ECX-2000 from Mark Langsdorf. - ARM vexpress/TC2 cpufreq support from Sudeep KarkadaNagesha. - ACPI power management support for the I2C and SPI bus types from Mika Westerberg and Lv Zheng. - cpufreq core fixes and cleanups from Viresh Kumar, Srivatsa S Bhat, Stratos Karafotis, Xiaoguang Chen, Lan Tianyu. - cpufreq drivers updates (mostly fixes and cleanups) from Viresh Kumar, Aaro Koskinen, Jungseok Lee, Sudeep KarkadaNagesha, Lukasz Majewski, Manish Badarkhe, Hans-Christian Egtvedt, Evgeny Kapaev. - intel_pstate updates from Dirk Brandewie and Adrian Huang. - ACPICA update to version 20130927 includig fixes and cleanups and some reduction of divergences between the ACPICA code in the kernel and ACPICA upstream in order to improve the automatic ACPICA patch generation process. From Bob Moore, Lv Zheng, Tomasz Nowicki, Naresh Bhat, Bjorn Helgaas, David E Box. - ACPI IPMI driver fixes and cleanups from Lv Zheng. - ACPI hotplug fixes and cleanups from Bjorn Helgaas, Toshi Kani, Zhang Yanfei, Rafael J Wysocki. - Conversion of the ACPI AC driver to the platform bus type and multiple driver fixes and cleanups related to ACPI from Zhang Rui. - ACPI processor driver fixes and cleanups from Hanjun Guo, Jiang Liu, Bartlomiej Zolnierkiewicz, Mathieu Rhéaume, Rafael J Wysocki. - Fixes and cleanups and new blacklist entries related to the ACPI video support from Aaron Lu, Felipe Contreras, Lennart Poettering, Kirill Tkhai. - cpuidle core cleanups from Viresh Kumar and Lorenzo Pieralisi. - cpuidle drivers fixes and cleanups from Daniel Lezcano, Jingoo Han, Bartlomiej Zolnierkiewicz, Prarit Bhargava. - devfreq updates from Sachin Kamat, Dan Carpenter, Manish Badarkhe. - Operation Performance Points (OPP) core updates from Nishanth Menon. - Runtime power management core fix from Rafael J Wysocki and update from Ulf Hansson. - Hibernation fixes from Aaron Lu and Rafael J Wysocki. - Device suspend/resume lockup detection mechanism from Benoit Goby. - Removal of unused proc directories created for various ACPI drivers from Lan Tianyu. - ACPI LPSS driver fix and new device IDs for the ACPI platform scan handler from Heikki Krogerus and Jarkko Nikula. - New ACPI _OSI blacklist entry for Toshiba NB100 from Levente Kurusa. - Assorted fixes and cleanups related to ACPI from Andy Shevchenko, Al Stone, Bartlomiej Zolnierkiewicz, Colin Ian King, Dan Carpenter, Felipe Contreras, Jianguo Wu, Lan Tianyu, Yinghai Lu, Mathias Krause, Liu Chuansheng. - Assorted PM fixes and cleanups from Andy Shevchenko, Thierry Reding, Jean-Christophe Plagniol-Villard. * tag 'pm+acpi-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (386 commits) cpufreq: conservative: fix requested_freq reduction issue ACPI / hotplug: Consolidate deferred execution of ACPI hotplug routines PM / runtime: Use pm_runtime_put_sync() in __device_release_driver() ACPI / event: remove unneeded NULL pointer check Revert "ACPI / video: Ignore BIOS initial backlight value for HP 250 G1" ACPI / video: Quirk initial backlight level 0 ACPI / video: Fix initial level validity test intel_pstate: skip the driver if ACPI has power mgmt option PM / hibernate: Avoid overflow in hibernate_preallocate_memory() ACPI / hotplug: Do not execute "insert in progress" _OST ACPI / hotplug: Carry out PCI root eject directly ACPI / hotplug: Merge device hot-removal routines ACPI / hotplug: Make acpi_bus_hot_remove_device() internal ACPI / hotplug: Simplify device ejection routines ACPI / hotplug: Fix handle_root_bridge_removal() ACPI / hotplug: Refuse to hot-remove all objects with disabled hotplug ACPI / scan: Start matching drivers after trying scan handlers ACPI: Remove acpi_pci_slot_init() headers from internal.h ACPI / blacklist: fix name of ThinkPad Edge E530 PowerCap: Fix build error with option -Werror=format-security ... Conflicts: arch/arm/mach-omap2/opp.c drivers/Kconfig drivers/spi/spi.c
2013-09-25sched, idle: Fix the idle polling state logicPeter Zijlstra
Mike reported that commit 7d1a9417 ("x86: Use generic idle loop") regressed several workloads and caused excessive reschedule interrupts. The patch in question failed to notice that the x86 code had an inverted sense of the polling state versus the new generic code (x86: default polling, generic: default !polling). Fix the two prominent x86 mwait based idle drivers and introduce a few new generic polling helpers (fixing the wrong smp_mb__after_clear_bit usage). Also switch the idle routines to using tif_need_resched() which is an immediate TIF_NEED_RESCHED test as opposed to need_resched which will end up being slightly different. Reported-by: Mike Galbraith <bitbucket@online.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: lenb@kernel.org Cc: tglx@linutronix.de Link: http://lkml.kernel.org/n/tip-nc03imb0etuefmzybzj7sprf@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-24ACPI / processor: remove superfluous pr == NULL checksBartlomiej Zolnierkiewicz
The only acpi_processor_get_power_info_fadt() user (acpi_processor_get_power_info()) dereferences pr before calling the function. The only acpi_processor_hotplug() user (acpi_cpu_soft_notify()) checks for pr == NULL before calling the function. The only acpi_processor_cst_has_changed() user (acpi_processor_notify()) checks for pr == NULL before calling the function. The only acpi_processor_power_init() user (__acpi_processor_start()) dereferences pr before calling the function. Thus remove superfluous pr == NULL checks from affected functions. Also: While at it remove redundant brackets from acpi_processor_hotplug(). Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-14acpi: delete __cpuinit usage from all acpi filesPaul Gortmaker
The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. This removes all the drivers/acpi uses of the __cpuinit macros from all C files. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Len Brown <lenb@kernel.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: linux-acpi@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-06-19ACPI / PM: acpi_processor_suspend() can be staticFengguang Wu
Since acpi_processor_suspend() and acpi_processor_resume() need not be visible outside of the file they are defined in, make them static. [rjw: Changelog] Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-12ACPI / PM: Move processor suspend/resume to syscore_opsRafael J. Wysocki
The system suspend routine of the ACPI processor driver saves the BUS_MASTER_RLD register and its resume routine restores it. However, there can be only one such register in the system and it really should be saved after non-boot CPUs have been offlined and restored before they are put back online during resume. For this reason, move the saving and restoration of BUS_MASTER_RLD to syscore suspend and syscore resume, respectively, and drop the no longer necessary suspend/resume callbacks from the ACPI processor driver. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-23cpuidle: remove en_core_tk_irqen flagDaniel Lezcano
The en_core_tk_irqen flag is set in all the cpuidle driver which means it is not necessary to specify this flag. Remove the flag and the code related to it. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Kevin Hilman <khilman@linaro.org> # for mach-omap2/* Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-02cpuidle / ACPI: recover percpu ACPI processor cstateAlex Shi
Commit ac3ebafa81af76d6 "ACPI / idle: remove usage of the statedata" changed the percpu processor cstate to a unified cstate in ACPI idle. That caused all our NHM boxes to boot hang or panic. 2178751 Task dump for CPU 1: 2178752 swapper/1 R running task 6736 0 1 0x00000000 2178753 ffff8801e8029dc8 ffffffff8101cf96 ffff8801e8029e28 ffffffff813d294b 2178754 0000000000000f99 0000000000000003 00000000003cf654 0000000025c17d03 2178755 ffff8801e8029e38 ffff8801e74fc000 00000002590dc5c4 ffffffff8163cdb0 2178756 Call Trace: 2178757 [<ffffffff8101cf96>] ? acpi_processor_ffh_cstate_enter+0x2d/0x2f 2178758 [<ffffffff813d294b>] acpi_idle_enter_bm+0x1b1/0x236 2178759 [<ffffffff8163cdb0>] ? disable_cpuidle+0x10/0x10 2178760 [<ffffffff8163cdc2>] cpuidle_enter+0x12/0x14 2178761 [<ffffffff8163d286>] cpuidle_wrap_enter+0x2f/0x6d 2178762 [<ffffffff8163d2d4>] cpuidle_enter_tk+0x10/0x12 2178763 [<ffffffff8163cdd6>] cpuidle_enter_state+0x12/0x3a 2178764 [<ffffffff8163d4a7>] cpuidle_idle_call+0xe8/0x161 2178765 [<ffffffff81008d99>] cpu_idle+0x5e/0xa4 2178766 [<ffffffff8174c6c1>] start_secondary+0x1a9/0x1ad 2178767 Task dump for CPU 2: In fact, the ACPI idle is based on the assumption of difference percpu cstate structures that are necessary for the implementation to work cprrectly. A unique acpi_processor_cx is not sifficient by far. This patch is just a quick fix re-introducing the percpu cstates. If someone really wants to unify the ACPI cstates, please make sure that the whole software infrastructure is changed and take hardware as well as many different kinds of BIOS settings into account. [rjw: Changelog] Reported-by: LKP project <lkp@linux.intel.com> Reported-by: Xie ChanglongX <changlongx.xie@intel.com> Tested-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-18Merge branch 'misc' into releaseLen Brown
Conflicts: arch/x86/kernel/process.c Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-10x86 idle: remove mwait_idle() and "idle=mwait" cmdline paramLen Brown
mwait_idle() is a C1-only idle loop intended to be more efficient than HLT, starting on Pentium-4 HT-enabled processors. But mwait_idle() has been replaced by the more general mwait_idle_with_hints(), which handles both C1 and deeper C-states. ACPI processor_idle and intel_idle use only mwait_idle_with_hints(), and no longer use mwait_idle(). Here we simplify the x86 native idle code by removing mwait_idle(), and the "idle=mwait" bootparam used to invoke it. Since Linux 3.0 there has been a boot-time warning when "idle=mwait" was invoked saying it would be removed in 2012. This removal was also noted in the (now removed:-) feature-removal-schedule.txt. After this change, kernels configured with (CONFIG_ACPI=n && CONFIG_INTEL_IDLE=n) when run on hardware that supports MWAIT will simply use HLT. If MWAIT is desired on those systems, cpuidle and the cpuidle drivers above can be enabled. Signed-off-by: Len Brown <len.brown@intel.com> Cc: x86@kernel.org
2013-02-08ACPI / idle: remove usage of the statedataDaniel Lezcano
Len Brown sent a patch to remove this field in the intel_idle driver. The other user of this field is the davinci cpuidle driver and a patch has been sent to remove the usage of it. This patch removes the last user of this field. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-08ACPI / idle: pass the cpuidle_device parameterDaniel Lezcano
The cpuidle_device is retrieved in the function by using directly the global variable. But the caller of this function already have this device and it can be passed as a parameter. That is one small step to encapsulate the code more. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-08ACPI / idle : remove pointless headersDaniel Lezcano
These different headers are not needed. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-08ACPI / idle: remove unused definitionDaniel Lezcano
The different definitions are not used anywhere in the code. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Len Brown <len.brown@intel.com>
2013-01-19ACPI / processor: Get power info before updating the C-statesThomas Schlichter
acpi_processor_get_power_info() has to be called before acpi_processor_setup_cpuidle_states() to have the latest information available. This fixes the missing C-state information after AC-->DC transition. Signed-off-by: Thomas Schlichter <thomas.schlichter@web.de> Cc: <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-18ACPI / cpuidle: Fix NULL pointer issues when cpuidle is disabledKonrad Rzeszutek Wilk
If cpuidle is disabled, that means that: per_cpu(acpi_cpuidle_device, pr->id) is set to NULL as the acpi_processor_power_init ends up failing at retval = cpuidle_register_driver(&acpi_idle_driver) (in acpi_processor_power_init) and never sets the per_cpu idle device. So when acpi_processor_hotplug on CPU online notification tries to reference said device it crashes: cpu 3 spinlock event irq 62 BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 IP: [<ffffffff81381013>] acpi_processor_setup_cpuidle_cx+0x3f/0x105 PGD a259b067 PUD ab38b067 PMD 0 Oops: 0002 [#1] SMP odules linked in: dm_multipath dm_mod xen_evtchn iscsi_boot_sysfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi libcrc32c crc32c nouveau mxm_wmi wmi radeon ttm sg sr_mod sd_mod cdrom ata_generic ata_piix libata crc32c_intel scsi_mod atl1c i915 fbcon tileblit font bitblit softcursor drm_kms_helper video xen_blkfront xen_netfront fb_sys_fops sysimgblt sysfillrect syscopyarea xenfs xen_privcmd mperf CPU 1 Pid: 3047, comm: bash Not tainted 3.8.0-rc3upstream-00250-g165c029 #1 MSI MS-7680/H61M-P23 (MS-7680) RIP: e030:[<ffffffff81381013>] [<ffffffff81381013>] acpi_processor_setup_cpuidle_cx+0x3f/0x105 RSP: e02b:ffff88001742dca8 EFLAGS: 00010202 RAX: 0000000000010be9 RBX: ffff8800a0a61800 RCX: ffff880105380000 RDX: 0000000000000003 RSI: 0000000000000200 RDI: ffff8800a0a61800 RBP: ffff88001742dce8 R08: ffffffff81812360 R09: 0000000000000200 R10: aaaaaaaaaaaaaaaa R11: 0000000000000001 R12: ffff8800a0a61800 R13: 00000000ffffff01 R14: 0000000000000000 R15: ffffffff81a907a0 FS: 00007fd6942f7700(0000) GS:ffff880105280000(0000) knlGS:0000000000000000 CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000004 CR3: 00000000a6773000 CR4: 0000000000042660 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process bash (pid: 3047, threadinfo ffff88001742c000, task ffff880017944000) Stack: 0000000000000150 ffff880100f59e00 ffff88001742dcd8 ffff8800a0a61800 0000000000000000 00000000ffffff01 0000000000000000 ffffffff81a907a0 ffff88001742dd18 ffffffff813815b1 ffff88001742dd08 ffffffff810ae336 Call Trace: [<ffffffff813815b1>] acpi_processor_hotplug+0x7c/0x9f [<ffffffff810ae336>] ? schedule_delayed_work_on+0x16/0x20 [<ffffffff8137ee8f>] acpi_cpu_soft_notify+0x90/0xca [<ffffffff8166023d>] notifier_call_chain+0x4d/0x70 [<ffffffff810bc369>] __raw_notifier_call_chain+0x9/0x10 [<ffffffff81094a4b>] __cpu_notify+0x1b/0x30 [<ffffffff81652cf7>] _cpu_up+0x103/0x14b [<ffffffff81652e18>] cpu_up+0xd9/0xec [<ffffffff8164a254>] store_online+0x94/0xd0 [<ffffffff814122fb>] dev_attr_store+0x1b/0x20 [<ffffffff81216404>] sysfs_write_file+0xf4/0x170 This patch fixes it. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-27cpuidle: Measure idle state durations with monotonic clockJulius Werner
Many cpuidle drivers measure their time spent in an idle state by reading the wallclock time before and after idling and calculating the difference. This leads to erroneous results when the wallclock time gets updated by another processor in the meantime, adding that clock adjustment to the idle state's time counter. If the clock adjustment was negative, the result is even worse due to an erroneous cast from int to unsigned long long of the last_residency variable. The negative 32 bit integer will zero-extend and result in a forward time jump of roughly four billion milliseconds or 1.3 hours on the idle state residency counter. This patch changes all affected cpuidle drivers to either use the monotonic clock for their measurements or make use of the generic time measurement wrapper in cpuidle.c, which was already working correctly. Some superfluous CLIs/STIs in the ACPI code are removed (interrupts should always already be disabled before entering the idle function, and not get reenabled until the generic wrapper has performed its second measurement). It also removes the erroneous cast, making sure that negative residency values are applied correctly even though they should not appear anymore. Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Tested-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Len Brown <len.brown@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-10-08cpuidle / ACPI: fix potential NULL pointer dereferenceWei Yongjun
The dereference should be moved below the NULL test. dpatch engine is used to auto generate this patch. (https://github.com/weiyj/dpatch) Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Len Brown <len.brown@intel.com>
2012-09-17cpuidle / ACPI : move cpuidle_device field out of the acpi_processor_power ↵Daniel Lezcano
structure Currently we have the cpuidle_device field in the acpi_processor_power structure. This adds a dependency between processor.h and cpuidle.h Although it is not a real problem, removing this dependency has the benefit of separating a bit more the cpuidle code from the rest of the acpi code. Also, the compilation should be a bit improved because we do no longer include cpuidle.h in processor.h. The preprocessor was generating 30418 loc and with this patch it generates 30256 loc for processor_thermal.c, a file which is not concerned at all by cpuidle, like processor_perflib.c and processor_throttling.c. That may sound ridiculous, but "small streams make big rivers" :P This patch moves this field into a static global per cpu variable like what is done in the intel_idle driver. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-15ACPI / processor: remove unused function parameterDaniel Lezcano
The 'device' parameter is not used neither in acpi_processor_power_init and acpi_processor_power_exit. This patch removes it. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-05cpuidle / ACPI : remove power from acpi_processor_cx structureDaniel Lezcano
Remove the unused power field from struct struct acpi_processor_cx. [rjw: Modified changelog.] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-26Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux Pull ACPI & power management update from Len Brown: "Re-write of the turbostat tool. lower overhead was necessary for measuring very large system when they are very idle. IVB support in intel_idle It's what I run on my IVB, others should be able to also:-) ACPICA core update We have found some bugs due to divergence between Linux and the upstream ACPICA base. Most of these patches are to reduce that divergence to reduce the risk of future bugs. Some cpuidle updates, mostly for non-Intel More will be coming, as they depend on this part. Some thermal management changes needed by non-ACPI systems. Some _OST (OS Status Indication) updates for hot ACPI hot-plug." * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (51 commits) Thermal: Documentation update Thermal: Add Hysteresis attributes Thermal: Make Thermal trip points writeable ACPI/AC: prevent OOPS on some boxes due to missing check power_supply_register() return value check tools/power: turbostat: fix large c1% issue tools/power: turbostat v2 - re-write for efficiency ACPICA: Update to version 20120711 ACPICA: AcpiSrc: Fix some translation issues for Linux conversion ACPICA: Update header files copyrights to 2012 ACPICA: Add new ACPI table load/unload external interfaces ACPICA: Split file: tbxface.c -> tbxfload.c ACPICA: Add PCC address space to space ID decode function ACPICA: Fix some comment fields ACPICA: Table manager: deploy new firmware error/warning interfaces ACPICA: Add new interfaces for BIOS(firmware) errors and warnings ACPICA: Split exception code utilities to a new file, utexcep.c ACPI: acpi_pad: tune round_robin_time ACPICA: Update to version 20120620 ACPICA: Add support for implicit notify on multiple devices ACPICA: Update comments; no functional change ...
2012-07-26Merge branches 'acpi_pad', 'acpica', 'apei-bugzilla-43282', 'battery', ↵Len Brown
'cpuidle-coupled', 'cpuidle-tweaks', 'intel_idle-ivb', 'ost', 'red-hat-bz-772730', 'thermal', 'thermal-spear' and 'turbostat-v2' into release
2012-07-19Merge branch 'pm-acpi'Rafael J. Wysocki
* pm-acpi: (24 commits) olpc-xo15-sci: Use struct dev_pm_ops for power management ACPI / PM: Drop PM callbacks from the ACPI bus type ACPI / PM: Drop legacy driver PM callbacks that are not used any more ACPI / PM: Do not execute legacy driver PM callbacks acpi_power_meter: Use struct dev_pm_ops for power management fujitsu-tablet: Use struct dev_pm_ops for power management classmate-laptop: Use struct dev_pm_ops for power management xo15-ebook: Use struct dev_pm_ops for power management toshiba_bluetooth: Use struct dev_pm_ops for power management panasonic-laptop: Use struct dev_pm_ops for power management sony-laptop: Use struct dev_pm_ops for power management hp_accel: Use struct dev_pm_ops for power management toshiba_acpi: Use struct dev_pm_ops for power management ACPI: Use struct dev_pm_ops for power management in the SBS driver ACPI: Use struct dev_pm_ops for power management in the power driver ACPI: Use struct dev_pm_ops for power management in the button driver ACPI: Use struct dev_pm_ops for power management in the battery driver ACPI: Use struct dev_pm_ops for power management in the AC driver ACPI: Use struct dev_pm_ops for power management in processor driver ACPI: Use struct dev_pm_ops for power management in the thermal driver ...
2012-07-17cpuilde / ACPI: remove time from acpi_processor_cx structureDaniel Lezcano
Remove the time field as it is not used. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-17cpuidle / ACPI: remove usage from acpi_processor_cx structureDaniel Lezcano
Remove the usage field as it is not used. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-17cpuidle / ACPI : remove latency_ticks from acpi_processor_cx structureDaniel Lezcano
Remove the latency_ticks field as it is not used. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-17ACPICA: AcpiSrc: Fix some translation issues for Linux conversionBob Moore
Fixes issues like this: i_aSL -> iASL 00-7_f -> 00-7F local_fADT -> local_FADT execute_oSI -> execute_OSI Also, in function headers, the parameters are now translated to lower case (with underscores if necessary.) Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-07-10PM / cpuidle: System resume hang fix with cpuidlePreeti U Murthy
On certain bios, resume hangs if cpus are allowed to enter idle states during suspend [1]. This was fixed in apci idle driver [2].But intel_idle driver does not have this fix. Thus instead of replicating the fix in both the idle drivers, or in more platform specific idle drivers if needed, the more general cpuidle infrastructure could handle this. A suspend callback in cpuidle_driver could handle this fix. But a cpuidle_driver provides only basic functionalities like platform idle state detection capability and mechanisms to support entry and exit into CPU idle states. All other cpuidle functions are found in the cpuidle generic infrastructure for good reason that all cpuidle drivers, irrepective of their platforms will support these functions. One option therefore would be to register a suspend callback in cpuidle which handles this fix. This could be called through a PM_SUSPEND_PREPARE notifier. But this is too generic a notfier for a driver to handle. Also, ideally the job of cpuidle is not to handle side effects of suspend. It should expose the interfaces which "handle cpuidle 'during' suspend" or any other operation, which the subsystems call during that respective operation. The fix demands that during suspend, no cpus should be allowed to enter deep C-states. The interface cpuidle_uninstall_idle_handler() in cpuidle ensures that. Not just that it also kicks all the cpus which are already in idle out of their idle states which was being done during cpu hotplug through a CPU_DYING_FROZEN callbacks. Now the question arises about when during suspend should cpuidle_uninstall_idle_handler() be called. Since we are dealing with drivers it seems best to call this function during dpm_suspend(). Delaying the call till dpm_suspend_noirq() does no harm, as long as it is before cpu_hotplug_begin() to avoid race conditions with cpu hotpulg operations. In dpm_suspend_noirq(), it would be wise to place this call before suspend_device_irqs() to avoid ugly interactions with the same. Ananlogously, during resume. References: [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/674075. [2] http://marc.info/?l=linux-pm&m=133958534231884&w=2 Reported-and-tested-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-01ACPI: Use struct dev_pm_ops for power management in processor driverRafael J. Wysocki
Make the ACPI processor driver define its PM callbacks through a struct dev_pm_ops object rather than by using legacy PM hooks in struct acpi_device_ops. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-07-01ACPI / PM: Drop pm_message_t argument from device suspend callbackRafael J. Wysocki
None of the drivers implementing the ACPI device suspend callback uses the pm_message_t argument of it, so this argument may be dropped entirely from that callback. This will simplify switching the ACPI bus type to PM handling based on struct dev_pm_ops. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-06-27PM / ACPI: Fix suspend/resume regression caused by cpuidle cleanup.Deepthi Dharwar
Commit e978aa7d7d57d04eb5f88a7507c4fb98577def77 ( cpuidle: Move dev->last_residency update to driver enter routine; remove dev->last_state) was breaking suspend on laptops, as reported in the below link - https://lkml.org/lkml/2011/11/11/164 This was fixed in commit 3439a8da16bcad6b0982ece938c9f8299bb53584 (ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression) by removing acpi_idle_suspend flag. - https://lkml.org/lkml/2011/11/14/74 But this did fix did not work on all systems as Suspend/resume regression was reported on Lenovo S10-3 recently by Dave. - https://lkml.org/lkml/2012/5/27/115 It looked like with commit e978aa7d broke suspend and with commit 3439a8da resume was not working with acpi_idle driver. This patch fixes the regression that caused this issue in the first place. acpi_idle_suspend flag is essential on some x86 systems to prevent the cpus from going to deeper C-states when suspend is triggered ( commit b04e7bdb984 ) So reverting the commit 3439a8da is essential. By default, irqs are disabled in cpu_idle arch specific call and re-enabled in idle state return path . During suspend, the acpi_idle_suspend flag is set, which prevents the cpus from going to deeper idle states, it is essential to enabling the irqs in this return path too. To address the suspend issue, we were not re-enabling the interrupts while returning from acpi_idle_enter_bm() routine if acpi_idle_suspend flag is set. and this caused suspend failure. In addition to the above, to improve the readability of the code, return of -ENIVAL is replaced with -EBUSY in acpi_idle_suspend return path. Implying that the system is currently busy when suspend is in progress, which prevents the cpus from entering deeper C-states. Reported-and-Tested-by: Dav Hansen <dave@linux.vnet.ibm.com> Tested-by: Preeti Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Reviewed-by: Srivatsa S Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-04-06Merge branches 'idle-fix' and 'misc' into releaseLen Brown
2012-04-05ACPI processor: Use safe_halt() rather than halt() in acpi_idle_play_dead()Luck, Tony
ACPI code is shared by arch/x86 and arch/ia64. ia64 doesn't provide a plain "halt()" function. Use safe_halt() instead. Signed-off-by: Tony Luck <tony.luck@intel.com> Tested-by: Boris Ostrovsky <boris.ostrovsky@amd.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-03-30Merge branches 'acpica', 'bgrt', 'bz-11533', 'cpuidle', 'ec', 'hotplug', ↵Len Brown
'misc', 'red-hat-bz-727865', 'thermal', 'throttling', 'turbostat' and 'video' into release Signed-off-by: Len Brown <len.brown@intel.com>
2012-03-30ACPI: Fix unprotected smp_processor_id() in acpi_processor_cst_has_changed()Paul E. McKenney
The acpi_processor_cst_has_changed() function is invoked from a CPU_ONLINE or CPU_DEAD function, which might well execute on CPU 0 even though the CPU being hotplugged is some other CPU. In addition, acpi_processor_cst_has_changed() invokes smp_processor_id() without protection, resulting in splats when onlining CPUs. This commit therefore changes the smp_processor_id() to pr->id, as is used elsewhere in the code, for example, in acpi_processor_add(). Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Tested-by: Yong Zhang <yong.zhang0@gmail.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Len Brown <len.brown@intel.com>
2012-03-30idle, x86: Allow off-lined CPU to enter deeper C statesBoris Ostrovsky
Currently when a CPU is off-lined it enters either MWAIT-based idle or, if MWAIT is not desired or supported, HLT-based idle (which places the processor in C1 state). This patch allows processors without MWAIT support to stay in states deeper than C1. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com> Signed-off-by: Len Brown <len.brown@intel.com>
2011-11-12ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression)Rafael J. Wysocki
After commit e978aa7d7d57 ("cpuidle: Move dev->last_residency update to driver enter routine; remove dev->last_state") setting acpi_idle_suspend to 1 by acpi_processor_suspend() causes the ACPI cpuidle routines to return error codes continuously, which in turn causes cpuidle to lock up (hard). However, acpi_idle_suspend doesn't appear to be useful for any particular purpose (it's racy and doesn't really provide any real protection), so it can be removed, which makes the problem go away. Reported-and-tested-by: Tomas M. <tmezzadra@gmail.com> Reported-and-tested-by: Ferenc Wagner <wferi@niif.hu> Tested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-07Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: cpuidle: Single/Global registration of idle states cpuidle: Split cpuidle_state structure and move per-cpu statistics fields cpuidle: Remove CPUIDLE_FLAG_IGNORE and dev->prepare() cpuidle: Move dev->last_residency update to driver enter routine; remove dev->last_state ACPI: Fix CONFIG_ACPI_DOCK=n compiler warning ACPI: Export FADT pm_profile integer value to userspace thermal: Prevent polling from happening during system suspend ACPI: Drop ACPI_NO_HARDWARE_INIT ACPI atomicio: Convert width in bits to bytes in __acpi_ioremap_fast() PNPACPI: Simplify disabled resource registration ACPI: Fix possible recursive locking in hwregs.c ACPI: use kstrdup() mrst pmu: update comment tools/power turbostat: less verbose debugging
2011-11-06cpuidle: Single/Global registration of idle statesDeepthi Dharwar
This patch makes the cpuidle_states structure global (single copy) instead of per-cpu. The statistics needed on per-cpu basis by the governor are kept per-cpu. This simplifies the cpuidle subsystem as state registration is done by single cpu only. Having single copy of cpuidle_states saves memory. Rare case of asymmetric C-states can be handled within the cpuidle driver and architectures such as POWER do not have asymmetric C-states. Having single/global registration of all the idle states, dynamic C-state transitions on x86 are handled by the boot cpu. Here, the boot cpu would disable all the devices, re-populate the states and later enable all the devices, irrespective of the cpu that would receive the notification first. Reference: https://lkml.org/lkml/2011/4/25/83 Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Trinabh Gupta <g.trinabh@gmail.com> Tested-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Len Brown <len.brown@intel.com>
2011-11-06cpuidle: Split cpuidle_state structure and move per-cpu statistics fieldsDeepthi Dharwar
This is the first step towards global registration of cpuidle states. The statistics used primarily by the governor are per-cpu and have to be split from rest of the fields inside cpuidle_state, which would be made global i.e. single copy. The driver_data field is also per-cpu and moved. Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Trinabh Gupta <g.trinabh@gmail.com> Tested-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Len Brown <len.brown@intel.com>
2011-11-06cpuidle: Move dev->last_residency update to driver enter routine; remove ↵Deepthi Dharwar
dev->last_state Cpuidle governor only suggests the state to enter using the governor->select() interface, but allows the low level driver to override the recommended state. The actual entered state may be different because of software or hardware demotion. Software demotion is done by the back-end cpuidle driver and can be accounted correctly. Current cpuidle code uses last_state field to capture the actual state entered and based on that updates the statistics for the state entered. Ideally the driver enter routine should update the counters, and it should return the state actually entered rather than the time spent there. The generic cpuidle code should simply handle where the counters live in the sysfs namespace, not updating the counters. Reference: https://lkml.org/lkml/2011/3/25/52 Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Trinabh Gupta <g.trinabh@gmail.com> Tested-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Len Brown <len.brown@intel.com>