cpuidle: consolidate 2.6.22 cpuidle branch into one patch

commit e5a16b1f9eec0af7cfa0830304b41c1c0833cf9f
Author: Len Brown <len.brown@intel.com>
Date:   Tue Oct 2 23:44:44 2007 -0400

    cpuidle: shrink diff

    processor_idle.c |  440 +++++++++++++++++++++++++++++++++++++++++--
    1 file changed, 429 insertions(+), 11 deletions(-)

    Signed-off-by: Len Brown <len.brown@intel.com>

commit dfbb9d5aedfb18848a3e0d6f6e3e4969febb209c
Author: Len Brown <len.brown@intel.com>
Date:   Wed Sep 26 02:17:55 2007 -0400

    cpuidle: reduce diff size

    Reduces the cpuidle processor_idle.c diff vs 2.6.22 from this
     processor_idle.c | 2006 ++++++++++++++++++++++++++-----------------
     1 file changed, 1219 insertions(+), 787 deletions(-)

    to this:
     processor_idle.c |  502 +++++++++++++++++++++++++++++++++++++++----
     1 file changed, 458 insertions(+), 44 deletions(-)

    ...for the purpose of making the cpuilde patch less invasive
    and easier to review.

    no functional changes.  build tested only.

    Signed-off-by: Len Brown <len.brown@intel.com>

commit 889172fc915f5a7fe20f35b133cbd205ce69bf6c
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Sep 13 13:40:05 2007 -0700

    cpuidle: Retain old ACPI policy for !CONFIG_CPU_IDLE

    Retain the old policy in processor_idle, so that when CPU_IDLE is not
    configured, old C-state policy will still be used. This provides a
    clean gradual migration path from old ACPI policy to new cpuidle
    based policy.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 9544a8181edc7ecc33b3bfd69271571f98ed08bc
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Sep 13 13:39:17 2007 -0700

    cpuidle: Configure governors by default

    Quoting Len "Do not give an option to users to shoot themselves in the foot".

    Remove the configurability of ladder and menu governors as they are
    needed for default policy of cpuidle. That way users will not be able to
    have cpuidle without any policy loosing all C-state power savings.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 8975059a2c1e56cfe83d1bcf031bcf4cb39be743
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:27:07 2007 -0400

    CPUIDLE: load ACPI properly when CPUIDLE is disabled

    Change the registration return codes for when CPUIDLE
    support is not compiled into the kernel.  As a result, the ACPI
    processor driver will load properly even if CPUIDLE is unavailable.
    However, it may be possible to cleanup the ACPI processor driver further
    and eliminate some dead code paths.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit e0322e2b58dd1b12ec669bf84693efe0dc2414a8
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:26:06 2007 -0400

    CPUIDLE: remove cpuidle_get_bm_activity()

    Remove cpuidle_get_bm_activity() and updates governors
    accordingly.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 18a6e770d5c82ba26653e53d240caa617e09e9ab
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:58 2007 -0400

    CPUIDLE: max_cstate fix

    Currently max_cstate is limited to 0, resulting in no idle processor
    power management on ACPI platforms.  This patch restores the value to
    the array size.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 1fdc0887286179b40ce24bcdbde663172e205ef0
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:40 2007 -0400

    CPUIDLE: handle BM detection inside the ACPI Processor driver

    Update the ACPI processor driver to detect BM activity and
    limit state entry depth internally, rather than exposing such
    requirements to CPUIDLE.  As a result, CPUIDLE can drop this
    ACPI-specific interface and become more platform independent.  BM
    activity is now handled much more aggressively than it was in the
    original implementation, so some testing coverage may be needed to
    verify that this doesn't introduce any DMA buffer under-run issues.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 0ef38840db666f48e3cdd2b769da676c57228dd9
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:14 2007 -0400

    CPUIDLE: menu governor updates

    Tweak the menu governor to more effectively handle non-timer
    break events.  Non-timer break events are detected by comparing the
    actual sleep time to the expected sleep time.  In future revisions, it
    may be more reliable to use the timer data structures directly.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit bb4d74fca63fa96cf3ace644b15ae0f12b7df5a1
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:24:40 2007 -0400

    CPUIDLE: fix 'current_governor' sysfs entry

    Allow the "current_governor" sysfs entry to properly handle
    input terminated with '\n'.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit df3c71559bb69b125f1a48971bf0d17f78bbdf47
Author: Len Brown <len.brown@intel.com>
Date:   Sun Aug 12 02:00:45 2007 -0400

    cpuidle: fix IA64 build (again)

    Signed-off-by: Len Brown <len.brown@intel.com>

commit a02064579e3f9530fd31baae16b1fc46b5a7bca8
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:39:27 2007 -0400

    cpuidle: Remove support for runtime changing of max_cstate

    Remove support for runtime changeability of max_cstate. Drivers can use
    use latency APIs.

    max_cstate can still be used as a boot time option and dmi override.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 0912a44b13adf22f5e3f607d263aed23b4910d7e
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:39:16 2007 -0400

    cpuidle: Remove ACPI cstate_limit calls from ipw2100

    ipw2100 already has code to use accetable_latency interfaces to limit the
    C-state. Remove the calls to acpi_set_cstate_limit and acpi_get_cstate_limit
    as they are redundant.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit c649a76e76be6bff1fd770d0a775798813a3f6e0
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:35:39 2007 -0400

    cpuidle: compile fix for pause and resume functions

    Fix the compilation failure when cpuidle is not compiled in.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Acked-by: Adam Belay <adam.belay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 2305a5920fb8ee6ccec1c62ade05aa8351091d71
Author: Adam Belay <abelay@novell.com>
Date:   Thu Jul 19 00:49:00 2007 -0400

    cpuidle: re-write

    Some portions have been rewritten to make the code cleaner and lighter
    weight.  The following is a list of changes:

    1.) the state name is now included in the sysfs interface
    2.) detection, hotplug, and available state modifications are handled by
    CPUIDLE drivers directly
    3.) the CPUIDLE idle handler is only ever installed when at least one
    cpuidle_device is enabled and ready
    4.) the menu governor BM code no longer overflows
    5.) the sysfs attributes are now printed as unsigned integers, avoiding
    negative values
    6.) a variety of other small cleanups

    Also, Idle drivers are no longer swappable during runtime through the
    CPUIDLE sysfs inteface.  On i386 and x86_64 most idle handlers (e.g.
    poll, mwait, halt, etc.) don't benefit from an infrastructure that
    supports multiple states, so I think using a more general case idle
    handler selection mechanism would be cleaner.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Acked-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit df25b6b56955714e6e24b574d88d1fd11f0c3ee5
Author: Len Brown <len.brown@intel.com>
Date:   Tue Jul 24 17:08:21 2007 -0400

    cpuidle: fix IA64 buid

    Signed-off-by: Len Brown <len.brown@intel.com>

commit fd6ada4c14488755ff7068860078c437431fbccd
Author: Adrian Bunk <bunk@stusta.de>
Date:   Mon Jul 9 11:33:13 2007 -0700

    cpuidle: static

    make cpuidle_replace_governor() static

    Signed-off-by: Adrian Bunk <bunk@stusta.de>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit c1d4a2cebcadf2429c0c72e1d29aa2a9684c32e0
Author: Adrian Bunk <bunk@stusta.de>
Date:   Tue Jul 3 00:54:40 2007 -0400

    cpuidle: static

    This patch makes the needlessly global struct menu_governor static.

    Signed-off-by: Adrian Bunk <bunk@stusta.de>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit dbf8780c6e8d572c2c273da97ed1cca7608fd999
Author: Andrew Morton <akpm@linux-foundation.org>
Date:   Tue Jul 3 00:49:14 2007 -0400

    export symbol tick_nohz_get_sleep_length

    ERROR: "tick_nohz_get_sleep_length" [drivers/cpuidle/governors/menu.ko] undefined!
    ERROR: "tick_nohz_get_idle_jiffies" [drivers/cpuidle/governors/menu.ko] undefined!

    And please be sure to get your changes to core kernel suitably reviewed.

    Cc: Adam Belay <abelay@novell.com>
    Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: john stultz <johnstul@us.ibm.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 29f0e248e7017be15f99febf9143a2cef00b2961
Author: Andrew Morton <akpm@linux-foundation.org>
Date:   Tue Jul 3 00:43:04 2007 -0400

    tick.h needs hrtimer.h

    It uses hrtimers.

    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit e40cede7d63a029e92712a3fe02faee60cc38fb4
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:40:34 2007 -0400

    cpuidle: first round of documentation updates

    Documentation changes based on Pavel's feedback.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 83b42be2efece386976507555c29e7773a0dfcd1
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:39:25 2007 -0400

    cpuidle: add rating to the governors and pick the one with highest rating by default

    Introduce a governor rating scheme to pick the right governor by default.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit d2a74b8c5e8f22def4709330d4bfc4a29209b71c
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:38:08 2007 -0400

    cpuidle: make cpuidle sysfs driver governor switch off by default

    Make default cpuidle sysfs to show current_governor and current_driver in
    read-only mode.  More elaborate available_governors and available_drivers with
    writeable current_governor and current_driver interface only appear with
    "cpuidle_sysfs_switch" boot parameter.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 1f60a0e80bf83cf6b55c8845bbe5596ed8f6307b
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:37:00 2007 -0400

    cpuidle: menu governor: change the early break condition

    Change the C-state early break out algorithm in menu governor.

    We only look at early breakouts that result in wakeups shorter than idle
    state's target_residency.  If such a breakout is frequent enough, eliminate
    the particular idle state upto a timeout period.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 45a42095cf64b003b4a69be3ce7f434f97d7af51
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:35:38 2007 -0400

    cpuidle: fix uninitialized variable in sysfs routine

    Fix the uninitialized usage of ret.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 80dca7cdba3e6ee13eae277660873ab9584eb3be
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:34:16 2007 -0400

    cpuidle: reenable /proc/acpi//power interface for the time being

    Keep /proc/acpi/processor/CPU*/power around for a while as powertop depends
    on it. It will be marked deprecated and removed in future. powertop can use
    cpuidle interfaces instead.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 589c37c2646c5e3813a51255a5ee1159cb4c33fc
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:32:37 2007 -0400

    cpuidle: menu governor and hrtimer compile fix

    Compile fix for menu governor.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 0ba80bd9ab3ed304cb4f19b722e4cc6740588b5e
Author: Len Brown <len.brown@intel.com>
Date:   Thu May 31 22:51:43 2007 -0400

    cpuidle: build fix - cpuidle vs ipw2100 module

    ERROR: "acpi_set_cstate_limit" [drivers/net/wireless/ipw2100.ko] undefined!

    Signed-off-by: Len Brown <len.brown@intel.com>

commit d7d8fa7f96a7f7682be7c6cc0cc53fa7a18c3b58
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:47:07 2007 -0400

    cpuidle: add the 'menu' governor

    Here is my first take at implementing an idle PM governor that takes
    full advantage of NO_HZ.  I call it the 'menu' governor because it
    considers the full list of idle states before each entry.

    I've kept the implementation fairly simple.  It attempts to guess the
    next residency time and then chooses a state that would meet at least
    the break-even point between power savings and entry cost.  To this end,
    it selects the deepest idle state that satisfies the following
    constraints:
         1. If the idle time elapsed since bus master activity was detected
            is below a threshold (currently 20 ms), then limit the selection
            to C2-type or above.
         2. Do not choose a state with a break-even residency that exceeds
            the expected time remaining until the next timer interrupt.
         3. Do not choose a state with a break-even residency that exceeds
            the elapsed time between the last pair of break events,
            excluding timer interrupts.

    This governor has an advantage over "ladder" governor because it
    proactively checks how much time remains until the next timer interrupt
    using the tick infrastructure.  Also, it handles device interrupt
    activity more intelligently by not including timer interrupts in break
    event calculations.  Finally, it doesn't make policy decisions using the
    number of state entries, which can have variable residency times (NO_HZ
    makes these potentially very large), and instead only considers sleep
    time deltas.

    The menu governor can be selected during runtime using the cpuidle sysfs
    interface like so:
    "echo "menu" > /sys/devices/system/cpu/cpuidle/current_governor"

    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit a4bec7e65aa3b7488b879d971651cc99a6c410fe
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:47:03 2007 -0400

    cpuidle: export time until next timer interrupt using NO_HZ

    Expose information about the time remaining until the next
    timer interrupt expires by utilizing the dynticks infrastructure.
    Also modify the main idle loop to allow dynticks to handle
    non-interrupt break events (e.g. DMA).  Finally, expose sleep ticks
    information to external code.  Thomas Gleixner is responsible for much
    of the code in this patch.  However, I've made some additional changes,
    so I'm probably responsible if there are any bugs or oversights :)

    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 2929d8996fbc77f41a5ff86bb67cdde3ca7d2d72
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:46:58 2007 -0400

    cpuidle: governor API changes

    This patch prepares cpuidle for the menu governor.  It adds an optional
    stage after idle state entry to give the governor an opportunity to
    check why the state was exited.  Also it makes sure the idle loop
    returns after each state entry, allowing the appropriate dynticks code
    to run.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 3a7fd42f9825c3b03e364ca59baa751bb350775f
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Apr 26 00:03:59 2007 -0700

    cpuidle: hang fix

    Prevent hang on x86-64, when ACPI processor driver is added as a module on
    a system that does not support C-states.

    x86-64 expects all idle handlers to enable interrupts before returning from
    idle handler.  This is due to enter_idle(), exit_idle() races.  Make
    cpuidle_idle_call() confirm to this when there is no pm_idle_old.

    Also, cpuidle look at the return values of attch_driver() and set
    current_driver to NULL if attach fails on all CPUs.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 4893339a142afbd5b7c01ffadfd53d14746e858e
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:09 2007 +0800

    cpuidle: add support for max_cstate limit

    With CPUIDLE framework, the max_cstate (to limit max cpu c-state)
    parameter is ingored. Some systems require it to ignore C2/C3
    and some drivers like ipw require it too.

    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 43bbbbe1cb998cbd2df656f55bb3bfe30f30e7d1
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:13 2007 +0800

    cpuidle: add cpuidle_fore_redetect_devices API

    add cpuidle_force_redetect_devices API,
    which forces all CPU redetect idle states.
    Next patch will use it.

    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit d1edadd608f24836def5ec483d2edccfb37b1d19
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:01 2007 +0800

    cpuidle: fix sysfs related issue

    Fix the cpuidle sysfs issue.
    a. make kobject dynamicaly allocated
    b. fixed sysfs init issue to avoid suspend/resume issue

    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 7169a5cc0d67b263978859672e86c13c23a5570d
Author: Randy Dunlap <randy.dunlap@oracle.com>
Date:   Wed Mar 28 22:52:53 2007 -0400

    cpuidle: 1-bit field must be unsigned

    A 1-bit bitfield has no room for a sign bit.
    drivers/cpuidle/governors/ladder.c:54:16: error: dubious bitfield without explicit `signed' or `unsigned'

    Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 4658620158dc2fbd9e4bcb213c5b6fb5d05ba7d4
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Wed Mar 28 22:52:41 2007 -0400

    cpuidle: fix boot hang

    Patch for cpuidle boot hang reported by Larry Finger here.
    http://www.ussg.iu.edu/hypermail/linux/kernel/0703.2/2025.html

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Larry Finger <larry.finger@lwfinger.net>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit c17e168aa6e5fe3851baaae8df2fbc1cf11443a9
Author: Len Brown <len.brown@intel.com>
Date:   Wed Mar 7 04:37:53 2007 -0500

    cpuidle: ladder does not depend on ACPI

    build fix for CONFIG_ACPI=n

    In file included from drivers/cpuidle/governors/ladder.c:21:
    include/acpi/processor.h:88: error: expected specifier-qualifier-list before ‘acpi_integer’
    include/acpi/processor.h:106: error: expected specifier-qualifier-list before ‘acpi_integer’
    include/acpi/processor.h:168: error: expected specifier-qualifier-list before ‘acpi_handle’

    Signed-off-by: Len Brown <len.brown@intel.com>

commit 8c91d958246bde68db0c3f0c57b535962ce861cb
Author: Adrian Bunk <bunk@stusta.de>
Date:   Tue Mar 6 02:29:40 2007 -0800

    cpuidle: make code static

    This patch makes the following needlessly global code static:
    - driver.c: __cpuidle_find_driver()
    - governor.c: __cpuidle_find_governor()
    - ladder.c: struct ladder_governor

    Signed-off-by: Adrian Bunk <bunk@stusta.de>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Adam Belay <abelay@novell.com>
    Cc: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 0c39dc3187094c72c33ab65a64d2017b21f372d2
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Wed Mar 7 02:38:22 2007 -0500

    cpu_idle: fix build break

    This patch fixes a build breakage with !CONFIG_HOTPLUG_CPU and
    CONFIG_CPU_IDLE.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Adrian Bunk <bunk@stusta.de>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 8112e3b115659b07df340ef170515799c0105f82
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Mar 6 02:29:39 2007 -0800

    cpuidle: build fix for !CPU_IDLE

    Fix the compile issues when CPU_IDLE is not configured.

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Adam Belay <abelay@novell.com>
    Cc: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 1eb4431e9599cd25e0d9872f3c2c8986821839dd
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:54:57 2007 -0800

    cpuidle take2: Basic documentation for cpuidle

    Documentation for cpuidle infrastructure

    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit ef5f15a8b79123a047285ec2e3899108661df779
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:54:03 2007 -0800

    cpuidle take2: Hookup ACPI C-states driver with cpuidle

    Hookup ACPI C-states onto generic cpuidle infrastructure.

    drivers/acpi/procesor_idle.c is now a ACPI C-states driver that registers as
    a driver in cpuidle infrastructure and the policy part is removed from
    drivers/acpi/processor_idle.c. We use governor in cpuidle instead.

    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

commit 987196fa82d4db52c407e8c9d5dec884ba602183
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:52:57 2007 -0800

    cpuidle take2: Core cpuidle infrastructure

    Announcing 'cpuidle', a new CPU power management infrastructure to manage
    idle CPUs in a clean and efficient manner.
    cpuidle separates out the drivers that can provide support for multiple types
    of idle states and policy governors that decide on what idle state to use
    at run time.
    A cpuidle driver can support multiple idle states based on parameters like
    varying power consumption, wakeup latency, etc (ACPI C-states for example).
    A cpuidle governor can be usage model specific (laptop, server,
    laptop on battery etc).
    Main advantage of the infrastructure being, it allows independent development
    of drivers and governors and allows for better CPU power management.

    A huge thanks to Adam Belay and Shaohua Li who were part of this mini-project
    since its beginning and are greatly responsible for this patchset.

    This patch:

    Core cpuidle infrastructure.
    Introduces a new abstraction layer for cpuidle:
    * which manages drivers that can support multiple idles states. Drivers
      can be generic or particular to specific hardware/platform
    * allows pluging in multiple policy governors that can take idle state policy
      decision
    * The core also has a set of sysfs interfaces with which administrato can know
      about supported drivers and governors and switch them at run time.

    Signed-off-by: Adam Belay <abelay@novell.com>
    Signed-off-by: Shaohua Li <shaohua.li@intel.com>
    Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Len Brown <len.brown@intel.com>

3 files changed, 460 insertions, 52 deletions

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 12c09fafce9a..5d14d4f10b12 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -1043,14 +1043,6 @@ static int __init acpi_wake_gpes_always_on_setup(char *str)
 __setup("acpi_wake_gpes_always_on", acpi_wake_gpes_always_on_setup);
 
 /*
- * max_cstate is defined in the base kernel so modules can
- * change it w/o depending on the state of the processor module.
- */
-unsigned int max_cstate = ACPI_PROCESSOR_MAX_POWER;
-
-EXPORT_SYMBOL(max_cstate);
-
-/*
  * Acquire a spinlock.
  *
  * handle is a pointer to the spinlock_t.
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 9f11dc296cdd..a7351084f2f8 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -44,6 +44,7 @@
 #include <linux/seq_file.h>
 #include <linux/dmi.h>
 #include <linux/moduleparam.h>
+#include <linux/cpuidle.h>
 
 #include <asm/io.h>
 #include <asm/system.h>
@@ -1049,11 +1050,13 @@ static int __init acpi_processor_init(void)
                 return -ENOMEM;
         acpi_processor_dir->owner = THIS_MODULE;
 
+        result = cpuidle_register_driver(&acpi_idle_driver);
+        if (result < 0)
+                goto out_proc;
+
         result = acpi_bus_register_driver(&acpi_processor_driver);
-        if (result < 0) {
-                remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
-                return result;
-        }
+        if (result < 0)
+                goto out_cpuidle;
 
         acpi_processor_install_hotplug_notify();
 
@@ -1062,11 +1065,18 @@ static int __init acpi_processor_init(void)
         acpi_processor_ppc_init();
 
         return 0;
+
+out_cpuidle:
+        cpuidle_unregister_driver(&acpi_idle_driver);
+
+out_proc:
+        remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
+
+        return result;
 }
 
 static void __exit acpi_processor_exit(void)
 {
-
         acpi_processor_ppc_exit();
 
         acpi_thermal_cpufreq_exit();
@@ -1075,6 +1085,8 @@ static void __exit acpi_processor_exit(void)
 
         acpi_bus_unregister_driver(&acpi_processor_driver);
 
+        cpuidle_unregister_driver(&acpi_idle_driver);
+
         remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
 
         return;
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index f18261368e76..99da6a790857 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -40,6 +40,7 @@
 #include <linux/sched.h>        /* need_resched() */
 #include <linux/latency.h>
 #include <linux/clockchips.h>
+#include <linux/cpuidle.h>
 
 /*
  * Include the apic definitions for x86 to have the APIC timer related defines
@@ -64,14 +65,22 @@ ACPI_MODULE_NAME("processor_idle");
 #define ACPI_PROCESSOR_FILE_POWER       "power"
 #define US_TO_PM_TIMER_TICKS(t)         ((t * (PM_TIMER_FREQUENCY/1000)) / 1000)
 #define PM_TIMER_TICK_NS                (1000000000ULL/PM_TIMER_FREQUENCY)
+#ifndef CONFIG_CPU_IDLE
 #define C2_OVERHEAD                     4       /* 1us (3.579 ticks per us) */
 #define C3_OVERHEAD                     4       /* 1us (3.579 ticks per us) */
 static void (*pm_idle_save) (void) __read_mostly;
-module_param(max_cstate, uint, 0644);
+#else
+#define C2_OVERHEAD                     1       /* 1us */
+#define C3_OVERHEAD                     1       /* 1us */
+#endif
+#define PM_TIMER_TICKS_TO_US(p)         (((p) * 1000)/(PM_TIMER_FREQUENCY/1000))
 
+static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;
+module_param(max_cstate, uint, 0000);
 static unsigned int nocst __read_mostly;
 module_param(nocst, uint, 0000);
 
+#ifndef CONFIG_CPU_IDLE
 /*
  * bm_history -- bit-mask with a bit per jiffy of bus-master activity
  * 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms
@@ -82,9 +91,10 @@ module_param(nocst, uint, 0000);
 static unsigned int bm_history __read_mostly =
     (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1));
 module_param(bm_history, uint, 0644);
-/* --------------------------------------------------------------------------
-                                Power Management
-   -------------------------------------------------------------------------- */
+
+static int acpi_processor_set_power_policy(struct acpi_processor *pr);
+
+#endif
 
 /*
  * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3.
@@ -177,6 +187,18 @@ static inline u32 ticks_elapsed(u32 t1, u32 t2)
                 return ((0xFFFFFFFF - t1) + t2);
 }
 
+static inline u32 ticks_elapsed_in_us(u32 t1, u32 t2)
+{
+        if (t2 >= t1)
+                return PM_TIMER_TICKS_TO_US(t2 - t1);
+        else if (!(acpi_gbl_FADT.flags & ACPI_FADT_32BIT_TIMER))
+                return PM_TIMER_TICKS_TO_US(((0x00FFFFFF - t1) + t2) & 0x00FFFFFF);
+        else
+                return PM_TIMER_TICKS_TO_US((0xFFFFFFFF - t1) + t2);
+}
+
+#ifndef CONFIG_CPU_IDLE
+
 static void
 acpi_processor_power_activate(struct acpi_processor *pr,
                               struct acpi_processor_cx *new)
@@ -248,6 +270,7 @@ static void acpi_cstate_enter(struct acpi_processor_cx *cstate)
                 unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
         }
 }
+#endif /* !CONFIG_CPU_IDLE */
 
 #ifdef ARCH_APICTIMER_STOPS_ON_C3
 
@@ -342,6 +365,7 @@ int acpi_processor_resume(struct acpi_device * device)
         return 0;
 }
 
+#ifndef CONFIG_CPU_IDLE
 static void acpi_processor_idle(void)
 {
         struct acpi_processor *pr = NULL;
@@ -439,7 +463,7 @@ static void acpi_processor_idle(void)
          * an SMP system. We do it here instead of doing it at _CST/P_LVL
          * detection phase, to work cleanly with logical CPU hotplug.
          */
-        if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && 
+        if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
             !pr->flags.has_cst && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
                 cx = &pr->power.states[ACPI_STATE_C1];
 #endif
@@ -739,6 +763,7 @@ static int acpi_processor_set_power_policy(struct acpi_processor *pr)
 
         return 0;
 }
+#endif /* !CONFIG_CPU_IDLE */
 
 static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
 {
@@ -756,7 +781,7 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
 #ifndef CONFIG_HOTPLUG_CPU
         /*
          * Check for P_LVL2_UP flag before entering C2 and above on
-         * an SMP system. 
+         * an SMP system.
          */
         if ((num_online_cpus() > 1) &&
             !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
@@ -957,7 +982,12 @@ static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx)
          * Normalize the C2 latency to expidite policy
          */
         cx->valid = 1;
+
+#ifndef CONFIG_CPU_IDLE
         cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency);
+#else
+        cx->latency_ticks = cx->latency;
+#endif
 
         return;
 }
@@ -1037,7 +1067,12 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
          * use this in our C3 policy
          */
         cx->valid = 1;
+
+#ifndef CONFIG_CPU_IDLE
         cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency);
+#else
+        cx->latency_ticks = cx->latency;
+#endif
 
         return;
 }
@@ -1102,6 +1137,7 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
 
         pr->power.count = acpi_processor_power_verify(pr);
 
+#ifndef CONFIG_CPU_IDLE
         /*
          * Set Default Policy
          * ------------------
@@ -1113,6 +1149,7 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
         result = acpi_processor_set_power_policy(pr);
         if (result)
                 return result;
+#endif
 
         /*
          * if one state of type C2 or C3 is available, mark this
@@ -1129,35 +1166,6 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
         return 0;
 }
 
-int acpi_processor_cst_has_changed(struct acpi_processor *pr)
-{
-        int result = 0;
-
-
-        if (!pr)
-                return -EINVAL;
-
-        if (nocst) {
-                return -ENODEV;
-        }
-
-        if (!pr->flags.power_setup_done)
-                return -ENODEV;
-
-        /* Fall back to the default idle loop */
-        pm_idle = pm_idle_save;
-        synchronize_sched();    /* Relies on interrupts forcing exit from idle. */
-
-        pr->flags.power = 0;
-        result = acpi_processor_get_power_info(pr);
-        if ((pr->flags.power == 1) && (pr->flags.power_setup_done))
-                pm_idle = acpi_processor_idle;
-
-        return result;
-}
-
-/* proc interface */
-
 static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset)
 {
         struct acpi_processor *pr = seq->private;
@@ -1239,6 +1247,35 @@ static const struct file_operations acpi_processor_power_fops = {
         .release = single_release,
 };
 
+#ifndef CONFIG_CPU_IDLE
+
+int acpi_processor_cst_has_changed(struct acpi_processor *pr)
+{
+        int result = 0;
+
+
+        if (!pr)
+                return -EINVAL;
+
+        if (nocst) {
+                return -ENODEV;
+        }
+
+        if (!pr->flags.power_setup_done)
+                return -ENODEV;
+
+        /* Fall back to the default idle loop */
+        pm_idle = pm_idle_save;
+        synchronize_sched();    /* Relies on interrupts forcing exit from idle. */
+
+        pr->flags.power = 0;
+        result = acpi_processor_get_power_info(pr);
+        if ((pr->flags.power == 1) && (pr->flags.power_setup_done))
+                pm_idle = acpi_processor_idle;
+
+        return result;
+}
+
 #ifdef CONFIG_SMP
 static void smp_callback(void *v)
 {
@@ -1261,7 +1298,360 @@ static int acpi_processor_latency_notify(struct notifier_block *b,
 static struct notifier_block acpi_processor_latency_notifier = {
         .notifier_call = acpi_processor_latency_notify,
 };
+
+#endif
+
+#else /* CONFIG_CPU_IDLE */
+
+/**
+ * acpi_idle_bm_check - checks if bus master activity was detected
+ */
+static int acpi_idle_bm_check(void)
+{
+        u32 bm_status = 0;
+
+        acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
+        if (bm_status)
+                acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);
+        /*
+         * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect
+         * the true state of bus mastering activity; forcing us to
+         * manually check the BMIDEA bit of each IDE channel.
+         */
+        else if (errata.piix4.bmisx) {
+                if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)
+                    || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
+                        bm_status = 1;
+        }
+        return bm_status;
+}
+
+/**
+ * acpi_idle_update_bm_rld - updates the BM_RLD bit depending on target state
+ * @pr: the processor
+ * @target: the new target state
+ */
+static inline void acpi_idle_update_bm_rld(struct acpi_processor *pr,
+                                           struct acpi_processor_cx *target)
+{
+        if (pr->flags.bm_rld_set && target->type != ACPI_STATE_C3) {
+                acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0);
+                pr->flags.bm_rld_set = 0;
+        }
+
+        if (!pr->flags.bm_rld_set && target->type == ACPI_STATE_C3) {
+                acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1);
+                pr->flags.bm_rld_set = 1;
+        }
+}
+
+/**
+ * acpi_idle_do_entry - a helper function that does C2 and C3 type entry
+ * @cx: cstate data
+ */
+static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
+{
+        if (cx->space_id == ACPI_CSTATE_FFH) {
+                /* Call into architectural FFH based C-state */
+                acpi_processor_ffh_cstate_enter(cx);
+        } else {
+                int unused;
+                /* IO port based C-state */
+                inb(cx->address);
+                /* Dummy wait op - must do something useless after P_LVL2 read
+                   because chipsets cannot guarantee that STPCLK# signal
+                   gets asserted in time to freeze execution properly. */
+                unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
+        }
+}
+
+/**
+ * acpi_idle_enter_c1 - enters an ACPI C1 state-type
+ * @dev: the target CPU
+ * @state: the state data
+ *
+ * This is equivalent to the HALT instruction.
+ */
+static int acpi_idle_enter_c1(struct cpuidle_device *dev,
+                              struct cpuidle_state *state)
+{
+        struct acpi_processor *pr;
+        struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
+        pr = processors[smp_processor_id()];
+
+        if (unlikely(!pr))
+                return 0;
+
+        if (pr->flags.bm_check)
+                acpi_idle_update_bm_rld(pr, cx);
+
+        current_thread_info()->status &= ~TS_POLLING;
+        /*
+         * TS_POLLING-cleared state must be visible before we test
+         * NEED_RESCHED:
+         */
+        smp_mb();
+        if (!need_resched())
+                safe_halt();
+        current_thread_info()->status |= TS_POLLING;
+
+        cx->usage++;
+
+        return 0;
+}
+
+/**
+ * acpi_idle_enter_simple - enters an ACPI state without BM handling
+ * @dev: the target CPU
+ * @state: the state data
+ */
+static int acpi_idle_enter_simple(struct cpuidle_device *dev,
+                                  struct cpuidle_state *state)
+{
+        struct acpi_processor *pr;
+        struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
+        u32 t1, t2;
+        pr = processors[smp_processor_id()];
+
+        if (unlikely(!pr))
+                return 0;
+
+        if (pr->flags.bm_check)
+                acpi_idle_update_bm_rld(pr, cx);
+
+        local_irq_disable();
+        current_thread_info()->status &= ~TS_POLLING;
+        /*
+         * TS_POLLING-cleared state must be visible before we test
+         * NEED_RESCHED:
+         */
+        smp_mb();
+
+        if (unlikely(need_resched())) {
+                current_thread_info()->status |= TS_POLLING;
+                local_irq_enable();
+                return 0;
+        }
+
+        if (cx->type == ACPI_STATE_C3)
+                ACPI_FLUSH_CPU_CACHE();
+
+        t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+        acpi_state_timer_broadcast(pr, cx, 1);
+        acpi_idle_do_entry(cx);
+        t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+
+#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
+        /* TSC could halt in idle, so notify users */
+        mark_tsc_unstable("TSC halts in idle");;
+#endif
+
+        local_irq_enable();
+        current_thread_info()->status |= TS_POLLING;
+
+        cx->usage++;
+
+        acpi_state_timer_broadcast(pr, cx, 0);
+        cx->time += ticks_elapsed(t1, t2);
+        return ticks_elapsed_in_us(t1, t2);
+}
+
+static int c3_cpu_count;
+static DEFINE_SPINLOCK(c3_lock);
+
+/**
+ * acpi_idle_enter_bm - enters C3 with proper BM handling
+ * @dev: the target CPU
+ * @state: the state data
+ *
+ * If BM is detected, the deepest non-C3 idle state is entered instead.
+ */
+static int acpi_idle_enter_bm(struct cpuidle_device *dev,
+                              struct cpuidle_state *state)
+{
+        struct acpi_processor *pr;
+        struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
+        u32 t1, t2;
+        pr = processors[smp_processor_id()];
+
+        if (unlikely(!pr))
+                return 0;
+
+        local_irq_disable();
+        current_thread_info()->status &= ~TS_POLLING;
+        /*
+         * TS_POLLING-cleared state must be visible before we test
+         * NEED_RESCHED:
+         */
+        smp_mb();
+
+        if (unlikely(need_resched())) {
+                current_thread_info()->status |= TS_POLLING;
+                local_irq_enable();
+                return 0;
+        }
+
+        /*
+         * Must be done before busmaster disable as we might need to
+         * access HPET !
+         */
+        acpi_state_timer_broadcast(pr, cx, 1);
+
+        if (acpi_idle_bm_check()) {
+                cx = pr->power.bm_state;
+
+                acpi_idle_update_bm_rld(pr, cx);
+
+                t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+                acpi_idle_do_entry(cx);
+                t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+        } else {
+                acpi_idle_update_bm_rld(pr, cx);
+
+                spin_lock(&c3_lock);
+                c3_cpu_count++;
+                /* Disable bus master arbitration when all CPUs are in C3 */
+                if (c3_cpu_count == num_online_cpus())
+                        acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1);
+                spin_unlock(&c3_lock);
+
+                t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+                acpi_idle_do_entry(cx);
+                t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+
+                spin_lock(&c3_lock);
+                /* Re-enable bus master arbitration */
+                if (c3_cpu_count == num_online_cpus())
+                        acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0);
+                c3_cpu_count--;
+                spin_unlock(&c3_lock);
+        }
+
+#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
+        /* TSC could halt in idle, so notify users */
+        mark_tsc_unstable("TSC halts in idle");
+#endif
+
+        local_irq_enable();
+        current_thread_info()->status |= TS_POLLING;
+
+        cx->usage++;
+
+        acpi_state_timer_broadcast(pr, cx, 0);
+        cx->time += ticks_elapsed(t1, t2);
+        return ticks_elapsed_in_us(t1, t2);
+}
+
+struct cpuidle_driver acpi_idle_driver = {
+        .name =         "acpi_idle",
+        .owner =        THIS_MODULE,
+};
+
+/**
+ * acpi_processor_setup_cpuidle - prepares and configures CPUIDLE
+ * @pr: the ACPI processor
+ */
+static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
+{
+        int i, count = 0;
+        struct acpi_processor_cx *cx;
+        struct cpuidle_state *state;
+        struct cpuidle_device *dev = &pr->power.dev;
+
+        if (!pr->flags.power_setup_done)
+                return -EINVAL;
+
+        if (pr->flags.power == 0) {
+                return -EINVAL;
+        }
+
+        for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
+                cx = &pr->power.states[i];
+                state = &dev->states[count];
+
+                if (!cx->valid)
+                        continue;
+
+#ifdef CONFIG_HOTPLUG_CPU
+                if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+                    !pr->flags.has_cst &&
+                    !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
+                        continue;
 #endif
+                cpuidle_set_statedata(state, cx);
+
+                snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
+                state->exit_latency = cx->latency;
+                state->target_residency = cx->latency * 6;
+                state->power_usage = cx->power;
+
+                state->flags = 0;
+                switch (cx->type) {
+                        case ACPI_STATE_C1:
+                        state->flags |= CPUIDLE_FLAG_SHALLOW;
+                        state->enter = acpi_idle_enter_c1;
+                        break;
+
+                        case ACPI_STATE_C2:
+                        state->flags |= CPUIDLE_FLAG_BALANCED;
+                        state->flags |= CPUIDLE_FLAG_TIME_VALID;
+                        state->enter = acpi_idle_enter_simple;
+                        break;
+
+                        case ACPI_STATE_C3:
+                        state->flags |= CPUIDLE_FLAG_DEEP;
+                        state->flags |= CPUIDLE_FLAG_TIME_VALID;
+                        state->flags |= CPUIDLE_FLAG_CHECK_BM;
+                        state->enter = pr->flags.bm_check ?
+                                        acpi_idle_enter_bm :
+                                        acpi_idle_enter_simple;
+                        break;
+                }
+
+                count++;
+        }
+
+        dev->state_count = count;
+
+        if (!count)
+                return -EINVAL;
+
+        /* find the deepest state that can handle active BM */
+        if (pr->flags.bm_check) {
+                for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++)
+                        if (pr->power.states[i].type == ACPI_STATE_C3)
+                                break;
+                pr->power.bm_state = &pr->power.states[i-1];
+        }
+
+        return 0;
+}
+
+int acpi_processor_cst_has_changed(struct acpi_processor *pr)
+{
+        int ret;
+
+        if (!pr)
+                return -EINVAL;
+
+        if (nocst) {
+                return -ENODEV;
+        }
+
+        if (!pr->flags.power_setup_done)
+                return -ENODEV;
+
+        cpuidle_pause_and_lock();
+        cpuidle_disable_device(&pr->power.dev);
+        acpi_processor_get_power_info(pr);
+        acpi_processor_setup_cpuidle(pr);
+        ret = cpuidle_enable_device(&pr->power.dev);
+        cpuidle_resume_and_unlock();
+
+        return ret;
+}
+
+#endif /* CONFIG_CPU_IDLE */
 
 int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
                               struct acpi_device *device)
@@ -1279,7 +1669,7 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
                                "ACPI: processor limited to max C-state %d\n",
                                max_cstate);
                 first_run++;
-#ifdef CONFIG_SMP
+#if !defined (CONFIG_CPU_IDLE) && defined (CONFIG_SMP)
                 register_latency_notifier(&acpi_processor_latency_notifier);
 #endif
         }
@@ -1297,6 +1687,7 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
         }
 
         acpi_processor_get_power_info(pr);
+        pr->flags.power_setup_done = 1;
 
         /*
          * Install the idle handler if processor power management is supported.
@@ -1304,6 +1695,13 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
          * platforms that only support C1.
          */
         if ((pr->flags.power) && (!boot_option_idle_override)) {
+#ifdef CONFIG_CPU_IDLE
+                acpi_processor_setup_cpuidle(pr);
+                pr->power.dev.cpu = pr->id;
+                if (cpuidle_register_device(&pr->power.dev))
+                        return -EIO;
+#endif
+
                 printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id);
                 for (i = 1; i <= pr->power.count; i++)
                         if (pr->power.states[i].valid)
@@ -1311,10 +1709,12 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
                                        pr->power.states[i].type);
                 printk(")\n");
 
+#ifndef CONFIG_CPU_IDLE
                 if (pr->id == 0) {
                         pm_idle_save = pm_idle;
                         pm_idle = acpi_processor_idle;
                 }
+#endif
         }
 
         /* 'power' [R] */
@@ -1328,21 +1728,24 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
                 entry->owner = THIS_MODULE;
         }
 
-        pr->flags.power_setup_done = 1;
-
         return 0;
 }
 
 int acpi_processor_power_exit(struct acpi_processor *pr,
                               struct acpi_device *device)
 {
-
+#ifdef CONFIG_CPU_IDLE
+        if ((pr->flags.power) && (!boot_option_idle_override))
+                cpuidle_unregister_device(&pr->power.dev);
+#endif
         pr->flags.power_setup_done = 0;
 
         if (acpi_device_dir(device))
                 remove_proc_entry(ACPI_PROCESSOR_FILE_POWER,
                                   acpi_device_dir(device));
 
+#ifndef CONFIG_CPU_IDLE
+
         /* Unregister the idle handler when processor #0 is removed. */
         if (pr->id == 0) {
                 pm_idle = pm_idle_save;
@@ -1357,6 +1760,7 @@ int acpi_processor_power_exit(struct acpi_processor *pr,
                 unregister_latency_notifier(&acpi_processor_latency_notifier);
 #endif
         }
+#endif
 
         return 0;
 }