Commit Graph

2771 Commits

Author SHA1 Message Date
Len Brown
56dbed129d Merge branch 'linus' into idle-test 2011-01-12 18:06:06 -05:00
Len Brown
0aae9f923b ACPI: processor_idle: delete use of NOP CPUIDLE_FLAGs
CPUIDLE_FLAG_SHALLOW
CPUIDLE_FLAG_BALANCED
CPUIDLE_FLAG_DEEP
CPUIDLE_FLAG_CHECK_BM

were set by acpi_processor_setup_cpuidle(),
but never used by cpuidle or by acpi_idle.
So stop setting them.

Signed-off-by: Len Brown <len.brown@intel.com>
2011-01-12 12:47:31 -05:00
Thomas Renninger
d18960494f ACPI, intel_idle: Cleanup idle= internal variables
Having four variables for the same thing:
  idle_halt, idle_nomwait, force_mwait and boot_option_idle_overrides
is rather confusing and unnecessary complex.

if idle= boot param is passed, only set up one variable:
boot_option_idle_overrides

Introduces following functional changes/fixes:
  - intel_idle driver does not register if any idle=xy
    boot param is passed.
  - processor_idle.c will also not register a cpuidle driver
    and get active if idle=halt is passed.
    Before a cpuidle driver with one (C1, halt) state got registered
    Now the default_idle function will be used which finally uses
    the same idle call to enter sleep state (safe_halt()), but
    without registering a whole cpuidle driver.

That means idle= param will always avoid cpuidle drivers to register
with one exception (same behavior as before):
idle=nomwait
may still register acpi_idle cpuidle driver, but C1 will not use
mwait, but hlt. This can be a workaround for IO based deeper sleep
states where C1 mwait causes problems.

Signed-off-by: Thomas Renninger <trenn@suse.de>
cc: x86@kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>
2011-01-12 12:47:30 -05:00
Linus Torvalds
72eb6a7914 Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (30 commits)
  gameport: use this_cpu_read instead of lookup
  x86: udelay: Use this_cpu_read to avoid address calculation
  x86: Use this_cpu_inc_return for nmi counter
  x86: Replace uses of current_cpu_data with this_cpu ops
  x86: Use this_cpu_ops to optimize code
  vmstat: User per cpu atomics to avoid interrupt disable / enable
  irq_work: Use per cpu atomics instead of regular atomics
  cpuops: Use cmpxchg for xchg to avoid lock semantics
  x86: this_cpu_cmpxchg and this_cpu_xchg operations
  percpu: Generic this_cpu_cmpxchg() and this_cpu_xchg support
  percpu,x86: relocate this_cpu_add_return() and friends
  connector: Use this_cpu operations
  xen: Use this_cpu_inc_return
  taskstats: Use this_cpu_ops
  random: Use this_cpu_inc_return
  fs: Use this_cpu_inc_return in buffer.c
  highmem: Use this_cpu_xx_return() operations
  vmstat: Use this_cpu_inc_return for vm statistics
  x86: Support for this_cpu_add, sub, dec, inc_return
  percpu: Generic support for this_cpu_add, sub, dec, inc_return
  ...

Fixed up conflicts: in arch/x86/kernel/{apic/nmi.c, apic/x2apic_uv_x.c, process.c}
as per Tejun.
2011-01-07 17:02:58 -08:00
Linus Torvalds
017892c341 Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Fix APIC ID sizing bug on larger systems, clean up MAX_APICS confusion
  x86, acpi: Parse all SRAT cpu entries even above the cpu number limitation
  x86, acpi: Add MAX_LOCAL_APIC for 32bit
  x86: io_apic: Split setup_ioapic_ids_from_mpc()
  x86: io_apic: Fix CONFIG_X86_IO_APIC=n breakage
  x86: apic: Move probe_nr_irqs_gsi() into ioapic_init_mappings()
  x86: Allow platforms to force enable apic
2011-01-06 10:51:36 -08:00
Ingo Molnar
bc030d6cb9 Merge commit 'v2.6.37-rc8' into x86/apic
Conflicts:
	arch/x86/include/asm/io_apic.h

Merge reason: move to a fresh -rc, resolve the conflict.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-04 09:43:42 +01:00
Ingo Molnar
cc22219699 Merge commit 'v2.6.37-rc8' into perf/core
Merge reason: pick up latest -rc.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-04 08:08:54 +01:00
Len Brown
bbbcde9d96 Merge branches 'bugzilla-25412' and 'bugzilla-25302' into release 2010-12-26 17:05:07 -05:00
Rafael J. Wysocki
5acdb1af90 ACPI / ACPICA: Disable GPEs during initialization
GPEs with corresponding _Lxx/_Exx control methods need to be disabled
during initialization in case they have been enabled by the BIOS, so
that they don't fire up until they are enabled by acpi_update_gpes().

References: https://bugzilla.kernel.org/show_bug.cgi?id=25412
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-26 17:02:55 -05:00
Len Brown
cde44d1740 Revert "ACPI battery: update status upon sysfs query"
This reverts commit 3138b32d5e.

as it caused a crash upon battery removal:
https://bugzilla.kernel.org/show_bug.cgi?id=25302

Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-24 21:43:16 -05:00
Yinghai Lu
d3bd058826 x86, acpi: Parse all SRAT cpu entries even above the cpu number limitation
Recent Intel new system have different order in MADT, aka will list all thread0
at first, then all thread1.
But SRAT table still old order, it will list cpus in one socket all together.

If the user have compiled limited NR_CPUS or boot with nr_cpus=, could have missed
to put some cpus apic id to node mapping into apicid_to_node[].

for example for 4 sockets system with 64 cpus with nr_cpus=32 will get crash...

[    9.106288] Total of 32 processors activated (136190.88 BogoMIPS).
[    9.235021] divide error: 0000 [#1] SMP
[    9.235315] last sysfs file:
[    9.235481] CPU 1
[    9.235592] Modules linked in:
[    9.245398]
[    9.245478] Pid: 2, comm: kthreadd Not tainted 2.6.37-rc1-tip-yh-01782-ge92ef79-dirty #274      /Sun Fire x4800
[    9.265415] RIP: 0010:[<ffffffff81075a8f>]  [<ffffffff81075a8f>] select_task_rq_fair+0x4f0/0x623
...
[    9.645938] RIP  [<ffffffff81075a8f>] select_task_rq_fair+0x4f0/0x623
[    9.665356]  RSP <ffff88103f8d1c40>
[    9.665568] ---[ end trace 2296156d35fdfc87 ]---

So let just parse all cpu entries in SRAT.

Also add apicid checking with MAX_LOCAL_APIC, in case We could out of boundaries of
apicid_to_node[].

it fixes following bug too.
https://bugzilla.kernel.org/show_bug.cgi?id=22662

-v2: expand to 32bit according to hpa
   need to add MAX_LOCAL_APIC for 32bit

Reported-and-Tested-by: Wu Fengguang <fengguang.wu@intel.com>
Reported-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Tested-by: Myron Stowe <myron.stowe@hp.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4D0AD486.9020704@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-12-23 13:16:18 -08:00
Ingo Molnar
6c529a266b Merge commit 'v2.6.37-rc7' into perf/core
Merge reason: Pick up the latest -rc.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-22 11:53:23 +01:00
Rafael J. Wysocki
b581a7f9c3 ACPI: Execute _PRW for devices reported as inactive or not present
If a device is reported as inactive or not present by its _STA
control method, acpi_bus_check_add() skips it without evaluating its
_PRW method.  This leads to a problem when the device's _PRW method
points to a GPE, because in that case the GPE may be enabled by
ACPICA during the subsequent acpi_update_gpes() call which, in
turn, may cause a GPE storm to appear.

To avoid this issue, make acpi_bus_check_add() evaluate _PRW for
inactive or not present devices and register the wakeup GPE
information returned by them, so that acpi_update_gpes() does not
enable their GPEs unnecessarily.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-17 16:39:11 -05:00
Tejun Heo
275c8b9328 Merge branch 'this_cpu_ops' into for-2.6.38 2010-12-17 15:16:46 +01:00
Christoph Lameter
4a6f4fe837 drivers: Replace __get_cpu_var with __this_cpu_read if not used for an address.
__get_cpu_var() can be replaced with this_cpu_read and will then use a single
read instruction with implied address calculation to access the correct per cpu
instance.

However, the address of a per cpu variable passed to __this_cpu_read() cannot be
determed (since its an implied address conversion through segment prefixes).
Therefore apply this only to uses of __get_cpu_var where the addres of the
variable is not used.

V3->V4:
	- Move one instance of this_cpu_inc_return to a later patch
	  so that this one can go in without percpu infrastructrure
	  changes.

Sedat: fixed compile failure caused by an extra ')'.

Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2010-12-17 15:07:18 +01:00
Len Brown
23437b5c50 Merge branch 'bugzilla-23002' into release 2010-12-13 22:40:54 -05:00
Rafael J. Wysocki
291a73c9be ACPI / PM: Do not save/restore NVS on Sony Vaio VGN-NW130D
The saving of the NVS memory area during suspend and restoring it
during resume causes problems to appear on Sony Vaio VGN-NW130D, so
blacklist that machine to avoid those problems.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=23002

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-and-tested-by: Adriano <adriano.vilela@yahoo.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-13 22:40:38 -05:00
Len Brown
6cc5615f7c Merge branches 'bugzilla-15418', 'bugzilla-21722', 'bugzilla-22932', 'misc-2.6.37' and 'osi-regression' into release 2010-12-11 02:02:02 -05:00
Jan Beulich
bec4f22a2d ACPI/HEST: adjust section selection
Properly const-, __init-, and __read_mostly-annotate this code.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-11 02:01:48 -05:00
Jan Beulich
091aad6af4 ACPI: eliminate unused variable warning for !ACPI_SLEEP
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-11 02:01:48 -05:00
Zhang Rui
b904759969 ACPI thermal: remove two unused functions
When CONFIG_CPU_FREQ=n ...

drivers/acpi/processor_thermal.c:159:12: warning: ‘acpi_thermal_cpufreq_increase’ defined but not used
drivers/acpi/processor_thermal.c:163:12: warning: ‘acpi_thermal_cpufreq_decrease’ defined but not used

Remove unused declaration of ‘acpi_thermal_cpufreq_increase’ and
‘acpi_thermal_cpufreq_decrease’

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-11 02:01:47 -05:00
Zhang Rui
32d47eeff0 ACPI: fix a section mismatch
WARNING: drivers/acpi/acpi.o(.text+0xeda): Section mismatch in reference from the function acpi_os_initialize1() to the function .init.text:set_osi_linux()

The function acpi_os_initialize1() references
the function __init set_osi_linux().

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-11 02:01:47 -05:00
Huang Ying
3b38bb5f7f ACPI, APEI, use raw spinlock in ERST
ERST writing may be used in NMI or Machine Check Exception handler. So
it need to use raw spinlock instead of normal spinlock.  This patch
fixes it.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-11 02:01:46 -05:00
Lin Ming
12d3206466 ACPI: fix allowing to add/remove multiple _OSI strings
commit b0ed7a91(ACPICA/ACPI: Add new host interfaces for _OSI suppor)
introduced another regression that only one _OSI string can be added or
removed.

Now multiple _OSI strings can be added or removed, for example

acpi_osi=Linux acpi_osi=FreeBSD acpi_osi="!Windows 2006"

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-11 01:31:01 -05:00
Lin Ming
d90aa92c0c acpi: fix _OSI string setup regression
commit b0ed7a91(ACPICA/ACPI: Add new host interfaces for _OSI suppor)
introduced a regression that _OSI string setup fails.

There are 2 paths to setup _OSI string.

DMI:
acpi_dmi_osi_linux -> set_osi_linux -> acpi_osi_setup -> copy _OSI
string to osi_setup_string

Boot command line:
acpi_osi_setup -> copy _OSI string to osi_setup_string

Later, acpi_osi_setup_late will be called to handle osi_setup_string.
If _OSI string is "Linux" or "!Linux", then the call path is,

acpi_osi_setup_late -> acpi_cmdline_osi_linux -> set_osi_linux ->
acpi_osi_setup -> copy _OSI string to osi_setup_string

This actually never installs _OSI string(acpi_install_interface not
called), but just copy the _OSI string to osi_setup_string.

This patch fixes the regression.

Reported-and-tested-by: Lukas Hejtmanek <xhejtman@ics.muni.cz>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-11 01:28:58 -05:00
Alexey Starikovskiy
a5dc4f898c ACPI: EC: Add another dmi match entry for MSI hardware
http://bugzilla.kernel.org/show_bug.cgi?id=15418

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
cc: stable@kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-09 17:08:46 -05:00
Zhang Rui
3138b32d5e ACPI battery: update status upon sysfs query
Sometimes the Battery driver doesn't get notifications when it's
plugged/unplugged. And this results in the incorrect Battery
status reported by the power supply sysfs I/F.

Update Battery status first when querying from sysfs.
http://marc.info/?l=linux-acpi&m=128855015826728&w=2

Tested_by: Seblu <seblu@seblu.net>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-09 15:34:57 -05:00
Zhang Rui
3151dbb04a ACPI ac: update AC status upon sysfs query
http://marc.info/?l=linux-acpi&m=128855015826728&w=2
https://bugzilla.kernel.org/show_bug.cgi?id=21722

Tested_by: Seblu <seblu@seblu.net>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-09 15:33:08 -05:00
Rafael J. Wysocki
12b3b5afed ACPI / PM: Do not refcount power resources that can't be turned on
If turning on a power resource fails, do not reference count it,
since it cannot be in use in that case.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-01 16:53:39 -05:00
Rafael J. Wysocki
212967c69a ACPI / PM: Check device state before refcounting power resources
Commit 3e384ee6c6 (ACPI / PM: Fix
reference counting of power resources) introduced a regression by
causing fan power resources to be turned on and reference counted
unnecessarily during resume, so on some boxes fans are always on
after resume.

Fix the problem by checking if the current device state is different
from the new state before reference counting and turning on power
resources in acpi_power_transition().

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=22932 .

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-and-tested-by: Maciej Rutecki <maciej.rutecki@gmail.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-12-01 16:53:16 -05:00
Don Zickus
072b198a4a x86, nmi_watchdog: Remove all stub function calls from old nmi_watchdog
Now that the bulk of the old nmi_watchdog is gone, remove all
the stub variables and hooks associated with it.

This touches lots of files mainly because of how the io_apic
nmi_watchdog was implemented.  Now that the io_apic nmi_watchdog
is forever gone, remove all its fingers.

Most of this code was not being exercised by virtue of
nmi_watchdog != NMI_IO_APIC, so there shouldn't be anything to
risky here.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: fweisbec@gmail.com
Cc: gorcunov@openvz.org
LKML-Reference: <1289578944-28564-3-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-18 09:08:23 +01:00
Dave Jones
ed3aada1bf ACPI: debugfs custom_method open to non-root
Currently we have:

  --w--w--w-. 1 root root 0 2010-11-11 14:56 /sys/kernel/debug/acpi/custom_method

which is just crazy. Change this to --w-------.

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: stable@kernel.org (for 2.6.36)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-13 09:52:16 -08:00
Linus Torvalds
474829e875 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (53 commits)
  ACPI: install ACPI table handler before any dynamic tables being loaded
  ACPI / PM: Blacklist another machine that needs acpi_sleep=nonvs
  ACPI: Page based coalescing of I/O remappings optimization
  ACPI: Convert simple locking to RCU based locking
  ACPI: Pre-map 'system event' related register blocks
  ACPI: Add interfaces for ioremapping/iounmapping ACPI registers
  ACPI: Maintain a list of ACPI memory mapped I/O remappings
  ACPI: Fix ioremap size for MMIO reads and writes
  ACPI / Battery: Return -ENODEV for unknown values in get_property()
  ACPI / PM: Fix reference counting of power resources
  Subject: [PATCH] ACPICA: Fix Scope() op in module level code
  ACPI battery: support percentage battery remaining capacity
  ACPI: Make Embedded Controller command timeout delay configurable
  ACPI dock: move some functions to .init.text
  ACPI: thermal: remove unused limit code
  ACPI: static sleep_states[] and acpi_gts_bfs_check
  ACPI: remove dead code
  ACPI: delete dedicated MAINTAINERS entries for ACPI EC and BATTERY drivers
  ACPI: Only processor needs CPU_IDLE
  ACPICA: Update version to 20101013
  ...
2010-10-26 17:28:37 -07:00
Linus Torvalds
27afe58fe6 Merge branch 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6
* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
  intel_idle: do not use the LAPIC timer for ATOM C2
  intel_idle: add initial Sandy Bridge support
  acpi_idle: delete bogus data from cpuidle_state.power_usage
  intel_idle: delete bogus data from cpuidle_state.power_usage
  intel_idle: simplify test for leave_mm()
2010-10-26 17:28:07 -07:00
Len Brown
7e31842441 Merge branch 'misc' into release 2010-10-26 14:51:00 -04:00
Len Brown
1bd64d42ab Merge branch 'acpi-mmio' into release
Conflicts:
	drivers/acpi/osl.c

Signed-off-by: Len Brown <len.brown@intel.com>
2010-10-26 14:50:56 -04:00
Zhang Rui
b1d248d96c ACPI: install ACPI table handler before any dynamic tables being loaded
ACPI table sysfs I/F is broken by commit

78f1699659
Author: Alex Chiang <achiang@hp.com>
Date:   Sun Dec 20 12:19:09 2009 -0700
    ACPI: processor: call _PDC early

because dynamic SSDT tables may be loaded in _PDC,
before installing the ACPI table handler.
As a result, the sysfs I/F of these dynamic tables are
located at  /sys/firmware/acpi/tables instead of
/sys/firmware/acpi/tables/dynamic, which is not true.

Invoke acpi_sysfs_init() before acpi_early_processor_set_pdc(),
so that the table handler is installed before any dynamic tables loaded.

https://bugzilla.kernel.org/show_bug.cgi?id=21142

CC: Dennis Jansen <dennis.jansen@web.de>
CC: Alex Chiang <achiang@hp.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-10-26 04:55:29 -04:00
Rafael J. Wysocki
af48931c48 ACPI / PM: Blacklist another machine that needs acpi_sleep=nonvs
Sony Vaio VPCEB1Z1E is reported to require acpi_sleep=nonvs for
suspend/resume to work on it correctly, so blacklist it.

Reported-by: Emanuele Bigiarini <pulmro@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-10-25 20:12:12 -04:00
Len Brown
4895ae6f9f Merge branch 'ec-param' into release 2010-10-25 02:14:50 -04:00
Len Brown
22156ea7bb Merge branch 'power-refcount' into release 2010-10-25 02:13:37 -04:00
Len Brown
d3b683d3b0 Merge branch 'cleanup' into release 2010-10-25 02:13:21 -04:00
Len Brown
6e04c417ae Merge branch 'gpe-defer' into release 2010-10-25 02:13:09 -04:00
Len Brown
880308089d Merge branch 'battery' into release 2010-10-25 02:12:57 -04:00
Len Brown
e000f8f729 Merge branch 'acpi_pm_device_sleep_state' into release 2010-10-25 02:12:46 -04:00
Len Brown
38add9b4ba Merge branches 'bugzilla-15807', 'bugzilla-15979-v2' and 'bugzilla-19162' into release 2010-10-25 02:12:27 -04:00
Len Brown
f3ab69a321 Merge branch 'procfs-cleanup-v2' into release 2010-10-25 02:11:49 -04:00
Len Brown
aca209e5e6 Merge branch 'acpica' into release
Conflicts:
	drivers/acpi/acpica/aclocal.h

Signed-off-by: Len Brown <len.brown@intel.com>
2010-10-25 02:10:36 -04:00
Myron Stowe
4a3cba5e72 ACPI: Page based coalescing of I/O remappings optimization
This patch optimizes ACPI MMIO remappings by keeping track of the
remappings on a PAGE_SIZE granularity.

When an ioremap() occurs, the underlying infrastructure works on a 'page'
based granularity.  As such, an ioremap() request for 1 byte for example,
will end up mapping in an entire (PAGE_SIZE) page.  Huang Ying took
advantage of this in commit 15651291a2 by
checking if subsequent ioremap() requests reside within any of the list's
existing remappings still in place, and if so, incrementing a reference
count on the existing mapping as opposed to performing another ioremap().

Signed-off-by: Myron Stowe <myron.stowe@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-10-24 23:31:43 -04:00
Myron Stowe
78cdb3ed40 ACPI: Convert simple locking to RCU based locking
Convert the simple locking introduced earlier for the ACPI MMIO
remappings list to an RCU based locking scheme.

Signed-off-by: Myron Stowe <myron.stowe@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-10-24 23:28:16 -04:00
Myron Stowe
d362edaf53 ACPI: Pre-map 'system event' related register blocks
During ACPI initialization, pre-map fixed hardware registers that are
accessed during ACPI's 'system event' related IRQ handing.

ACPI's 'system event' handing accesses specific fixed hardware
registers; namely PM1a event, PM1b event, GPE0, and GPE1 register
blocks which are declared within the FADT.  If these registers are
backed by MMIO, as opposed to I/O port space, accessing them within
interrupt context will cause a panic as acpi_os_read_memory()
depends on ioremap() in such cases - BZ 18012.

By utilizing the functionality provided in the previous two patches -
ACPI: Maintain a list of ACPI memory mapped I/O remappings, and, ACPI:
Add interfaces for ioremapping/iounmapping ACPI registers - accesses
to ACPI MMIO areas will now be safe from within interrupt contexts (IRQ
and/or NMI) provided the area was pre-mapped.  This solves BZ 18012.

ACPI "System Event" reference(s):
  ACPI Specification, Revision 4.0, Section 3 "ACPI Overview",
  3.8 "System Events", 5.6 "ACPI Event Programming Model".

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=18012

Reported-by: <bjorn.helgaas@hp.com>
Signed-off-by: Myron Stowe <myron.stowe@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-10-24 23:27:09 -04:00