Commit Graph

270 Commits

Author SHA1 Message Date
Rafael J. Wysocki
4def8a360f Merge branch 'acpi-video'
* acpi-video: (38 commits)
  ACPI / video: Make acpi_video_unregister_backlight() private
  acpi-video-detect: Remove old API
  toshiba-acpi: Port to new backlight interface selection API
  thinkpad-acpi: Port to new backlight interface selection API
  sony-laptop: Port to new backlight interface selection API
  samsung-laptop: Port to new backlight interface selection API
  msi-wmi: Port to new backlight interface selection API
  msi-laptop: Port to new backlight interface selection API
  intel-oaktrail: Port to new backlight interface selection API
  ideapad-laptop: Port to new backlight interface selection API
  fujitsu-laptop: Port to new backlight interface selection API
  eeepc-laptop: Port to new backlight interface selection API
  dell-wmi: Port to new backlight interface selection API
  dell-laptop: Port to new backlight interface selection API
  compal-laptop: Port to new backlight interface selection API
  asus-wmi: Port to new backlight interface selection API
  asus-laptop: Port to new backlight interface selection API
  apple-gmux: Port to new backlight interface selection API
  acer-wmi: Port to new backlight interface selection API
  ACPI / video: Fix acpi_video _register vs _unregister_backlight race
  ...
2015-06-19 01:17:26 +02:00
Rafael J. Wysocki
4f1fd900c2 Merge branches 'acpi-pm', 'acpi-apei', 'acpi-osl' and 'acpi-pci'
* acpi-pm:
  ACPI / PM: Add missing pm_generic_complete() invocation
  ACPI / PM: Turn power resources on and off in the right order during resume
  ACPI / PM: Rework device power management to follow ACPI 6
  ACPI / PM: Drop stale comment from acpi_power_transition()

* acpi-apei:
  GHES: Make NMI handler have a single reader
  GHES: Elliminate double-loop in the NMI handler
  GHES: Panic right after detection
  GHES: Carve out the panic functionality
  GHES: Carve out error queueing in a separate function

* acpi-osl:
  ACPI / osl: use same type for acpi_predefined_names values as in definition

* acpi-pci:
  ACPI / PCI: remove stale list_head in struct acpi_prt_entry
2015-06-19 01:16:21 +02:00
Hans de Goede
a87878bafa acpi-video-detect: Move acpi_osi_is_win8 to osl.c
acpi_osi_is_win8 needs access to acpi_gbl_osi_data which is not exported,
so move it to osl.c. Alternatively we could export acpi_gbl_osi_data but
that seems undesirable.

This allows video_detect.c to be build as a module, besides that
acpi_osi_is_win8() is something which does not really belong in
video_detect.c in the first place.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-19 01:10:31 +02:00
Rafael J. Wysocki
0f1b414d19 ACPI / PNP: Avoid conflicting resource reservations
Commit b9a5e5e18f "ACPI / init: Fix the ordering of
acpi_reserve_resources()" overlooked the fact that the memory
and/or I/O regions reserved by acpi_reserve_resources() may
conflict with those reserved by the PNP "system" driver.

If that conflict actually takes place, it causes the reservations
made by the "system" driver to fail while before commit b9a5e5e18f
all reservations made by it and by acpi_reserve_resources() would be
successful.  In turn, that allows the resources that haven't been
reserved by the "system" driver to be used by others (e.g. PCI) which
sometimes leads to functional problems (up to and including boot
failures).

To fix that issue, introduce a common resource reservation routine,
acpi_reserve_region(), to be used by both acpi_reserve_resources()
and the "system" driver, that will track all resources reserved by
it and avoid making conflicting requests.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=99831
Link: http://marc.info/?t=143389402600001&r=1&w=2
Fixes: b9a5e5e18f "ACPI / init: Fix the ordering of acpi_reserve_resources()"
Reported-by: Roland Dreier <roland@purestorage.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-18 18:32:02 +02:00
Dominik Brodowski
2bad7e27e0 ACPI / osl: use same type for acpi_predefined_names values as in definition
In the definition of struct acpi_predefined_names, value is of
type char *. Make the OSL override function also work with type
char * (or, more precisely, with a pointer to it).

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-14 22:16:38 +02:00
Rafael J. Wysocki
b9a5e5e18f ACPI / init: Fix the ordering of acpi_reserve_resources()
Since acpi_reserve_resources() is defined as a device_initcall(),
there's no guarantee that it will be executed in the right order
with respect to the rest of the ACPI initialization code.  On some
systems this leads to breakage if, for example, the address range
that should be reserved for the ACPI fixed registers is given to
the PCI host bridge instead if the race is won by the wrong code
path.

Fix this by turning acpi_reserve_resources() into a void function
and calling it directly from within the ACPI initialization sequence.

Reported-and-tested-by: George McCollister <george.mccollister@gmail.com>
Link: http://marc.info/?t=143092384600002&r=1&w=2
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-07 21:19:39 +02:00
Graeme Gregory
aafc65c731 ACPI: add arm64 to the platforms that use ioremap
Now with the base changes to the arm memory mapping it is safe
to convert to using ioremap to map in the tables after
acpi_gbl_permanent_mmap is set.

CC: Rafael J Wysocki <rjw@rjwysocki.net>
Tested-by: Robert Richter <rrichter@cavium.com>
Tested-by: Timur Tabi <timur@codeaurora.org>
Acked-by: Robert Richter <rrichter@cavium.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Al Stone <al.stone@linaro.org>
Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-25 11:49:30 +00:00
Lv Zheng
90253a792e ACPI / OSL: Add IRQ handler flushing support in the OSL.
It is possible that a GPE handler or a fixed event handler still accessed
after removing the handlers by invoking acpi_remove_gpe_handler() or
acpi_remove_fixed_event_handler(), this possibility can crash OPSM after a
module removal. In the Linux kernel, though all other GPE drivers are not
modules, since the IPMI_SI (ipmi_si_intf.c) can be compiled as a module, we
still need to consider a solution for this issue when the driver switches
to ACPI_GPE_RAW_HANDLER mode in order to invoke GPE APIs.

ACPICA expects acpi_os_wait_events_complete() to be invoked after GPE
disabling so that OSPM can ensure all running GPE handlers have exitted.
But currently acpi_os_wait_events_complete() can only flush _Lxx/_Exx
evaluation work queue and this philosophy cannot work for drivers that have
installed a dedicated GPE handler.

The only way to protect a callback is to perform some state holders
(reference count, state machine) before invoking the callback. Then this
issue can only be fixed by the following means:
1. Flush GPE in ACPICA before invoking the GPE handler. But currently,
   there is no such implementation in acpi_ev_gpe_dispatch().
2. Flush GPE in ACPICA OSL before invoking the SCI handler. But currently,
   there is no such implementation in acpi_irq().
3. Flush IRQ in OSPM IRQ layer before invoking the IRQ handler. In Linus
   kernel, this can be done by synchronize_irq().
4. Flush scheduling in OSPM vector entry layer before invoking the vector.
   In Linux, this can be done by synchronize_sched().

Since ACPICA expects the GPE handlers to be flushed by the ACPICA OSL or
the GPE drivers. If it is implemented by the GPE driver, we should see
synchronize_irq()/synchronize_sched() invoked in such drivers. If it is
implemented by the ACPICA OSL, ACPICA currently provides
acpi_os_wait_events_complete() hook to achieve this. After the following
commit:
  Commit: 69c841b6dd
  Author: Lv Zheng <lv.zheng@intel.com>
  Subject: ACPICA: Update use of acpi_os_wait_events_complete interface.
The OSL acpi_os_wait_events_complete() is invoked after a GPE handler is
removed from acpi_remove_gpe_handler() or a fixed event handler is removed
from acpi_remove_fixed_event_handler(). Thus it is possible to implement
GPE handler flushing using this ACPICA OSL now. So the solution 1 is
currently not taken into account.

By examining the IPMI_SI driver, we noticed that the IPMI_SI driver:
1. Uses free_irq() to flush non GPE based IRQ handlers, in free_irq(),
   synchronize_irq() is invoked, and
2. Uses acpi_remove_gpe_handler() to flush GPE based IRQ handlers, for such
   IRQ handlers, there is no synchronize_irq() invoked.
Since there isn't synchronize_sched() implemented for this driver, from the
driver's perspective, acpi_remove_gpe_handler() should have properly
flushed the GPE handlers for it. Since the driver doesn't invoke
synchronize_irq(), the solution 3 is not what the drivers expect.

This patch implements solution 2. But since given the fact that the GPE is
managed inside of ACPICA, and implementing the GPE flushing requires to
implement the whole GPE management code again in the OSL, instead of
flushing GPE, this patch flushes IRQ in acpi_os_wait_events_complete(). The
flushing could last longer than expected as though the target GPE/fixed
event that is removed can be fastly flushed, other GPEs/fix events can still
be issued during the flushing period.

This patch fixes this issue by invoking synchronize_hardirq() in
acpi_os_wait_events_complete(). The reason why we don't invoke
synchronize_irq() is: currently ACPICA is not threaded IRQ capable and the
only difference between synchronize_irq() and synchronize_hardirq() is
synchronize_irq() also flushes threaded IRQ handlers. Thus using
synchronize_hardirq() can help to reduce the overall synchronization time
for the current ACPICA implementation.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: linux-acpi@vger.kernel.org
Cc: devel@acpica.org
Cc: openipmi-developer@lists.sourceforge.net
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-11 23:49:09 +01:00
Konstantin Khlebnikov
74b51ee152 ACPI / osl: speedup grace period in acpi_os_map_cleanup
ACPI maintains cache of ioremap regions to speed up operations and
access to them from irq context where ioremap() calls aren't allowed.
This code abuses synchronize_rcu() on unmap path for synchronization
with fast-path in acpi_os_read/write_memory which uses this cache.

Since v3.10 CPUs are allowed to enter idle state even if they have RCU
callbacks queued, see commit c0f4dfd4f9
("rcu: Make RCU_FAST_NO_HZ take advantage of numbered callbacks").
That change caused problems with nvidia proprietary driver which calls
acpi_os_map/unmap_generic_address several times during initialization.
Each unmap calls synchronize_rcu and adds significant delay. Totally
initialization is slowed for a couple of seconds and that is enough to
trigger timeout in hardware, gpu decides to "fell off the bus". Widely
spread workaround is reducing "rcu_idle_gp_delay" from 4 to 1 jiffy.

This patch replaces synchronize_rcu() with synchronize_rcu_expedited()
which is much faster.

Link: https://devtalk.nvidia.com/default/topic/567297/linux/linux-3-10-driver-crash/
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Reported-and-tested-by: Alexander Monakov <amonakov@gmail.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-11 21:44:58 +01:00
Rafael J. Wysocki
28c399e2a1 Merge branch 'acpi-pm'
* acpi-pm:
  ACPI / sleep: Rework the handling of ACPI GPE wakeup from suspend-to-idle
  PM / sleep: Rename platform suspend/resume functions in suspend.c
  PM / sleep: Export dpm_suspend_late/noirq() and dpm_resume_early/noirq()
2014-10-07 01:17:50 +02:00
Rafael J. Wysocki
a8d46b9e4e ACPI / sleep: Rework the handling of ACPI GPE wakeup from suspend-to-idle
The ACPI GPE wakeup from suspend-to-idle is currently based on using
the IRQF_NO_SUSPEND flag for the ACPI SCI, but that is problematic
for a couple of reasons.  First, in principle the ACPI SCI may be
shared and IRQF_NO_SUSPEND does not really work well with shared
interrupts.  Second, it may require the ACPI subsystem to special-case
the handling of device notifications depending on whether or not
they are received during suspend-to-idle in some places which would
lead to fragile code.  Finally, it's better the handle ACPI wakeup
interrupts consistently with wakeup interrupts from other sources.

For this reason, remove the IRQF_NO_SUSPEND flag from the ACPI SCI
and use enable_irq_wake()/disable_irq_wake() with it instead, which
requires two additional platform hooks to be added to struct
platform_freeze_ops.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-30 21:06:07 +02:00
Matthew Garrett
7bc5a2bad0 ACPI: Support _OSI("Darwin") correctly
Apple hardware queries _OSI("Darwin") in order to determine whether the
system is running OS X, and changes firmware behaviour based on the
answer.  The most obvious difference in behaviour is that Thunderbolt
hardware is forcibly powered down unless the system is running OS X. The
obvious solution would be to simply add Darwin to the list of supported
_OSI strings, but this causes problems.

Recent Apple hardware includes two separate methods for checking _OSI
strings. The first will check whether Darwin is supported, and if so
will exit. The second will check whether Darwin is supported, but will
then continue to check for further operating systems. If a further
operating system is found then later firmware code will assume that the
OS is not OS X.  This results in the unfortunate situation where the
Thunderbolt controller is available at boot time but remains powered
down after suspend.

The easiest way to handle this is to special-case it in the
Linux-specific OSI handling code. If we see Darwin, we should answer
true and then disable all other _OSI vendor strings.

The next problem is that the Apple PCI _OSC method has the following
code:

if (LEqual (0x01, OSDW ()))
  if (LAnd (LEqual (Arg0, GUID), NEXP)
    (do stuff)
  else
    (fail)
NEXP is a value in high memory and is presumably under the control of
the firmware. No methods sets it. The methods that are called in the "do
stuff" path are dummies. Unless there's some additional firmware call in
early boot, there's no way for this call to succeed - and even if it
does, it doesn't do anything.

The easiest way to handle this is simply to ignore it. We know which
flags would be set, so just set them by hand if the platform is running
in Darwin mode.

Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
[andreas.noever@gmail.com: merged two patches, do not touch ACPICA]
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-24 23:31:12 +02:00
Graeme Gregory
8a1664be0b ACPI: add config for BIOS table scan
With the addition of ARM64 that does not have a traditional BIOS to
scan, add a config option which is selected on x86 (ia64 doesn't need
it either, it is EFI/UEFI based system) to do the traditional BIOS
scanning for tables.

Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-21 13:50:58 +02:00
Christoph Jaeger
3d915894f8 ACPI: use kstrto*() instead of simple_strto*()
simple_strto*() are obsolete; use kstrto*() instead. Add proper error
checking.

Signed-off-by: Christoph Jaeger <christophjaeger@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-17 14:01:56 +02:00
Rafael J. Wysocki
de815a6d00 Merge branches 'acpi-general' and 'acpi-video'
* acpi-general:
  ACPI: Fix bug when ACPI reset register is implemented in system memory

* acpi-video:
  ACPI / video: Change the default for video.use_native_backlight to 1
2014-06-12 13:42:37 +02:00
Randy Wright
a4714a898e ACPI: Fix bug when ACPI reset register is implemented in system memory
Use acpi_os_map_generic_address to pre-map the reset register if it is
memory mapped, thereby preventing the BUG_ON() in line 1319 of
mm/vmalloc.c from triggering during panic-triggered reboots.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=77131
Signed-off-by: Randy Wright <rwright@hp.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
[rjw: Changelog, simplified code]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-05 14:36:40 +02:00
Lv Zheng
a238317ce8 ACPI: Clean up acpi_os_map/unmap_memory() to eliminate __iomem.
ACPICA doesn't include protections around address space checking, Linux
build tests always complain increased sparse warnings around ACPICA
internal acpi_os_map/unmap_memory() invocations.  This patch tries to fix
this issue permanently.

There are 2 choices left for us to solve this issue:
 1. Add __iomem address space awareness into ACPICA.
 2. Remove sparse checker of __iomem from ACPICA source code.

This patch chooses solution 2, because:
 1.  Most of the acpi_os_map/unmap_memory() invocations are used for ACPICA.
     table mappings, which in fact are not IO addresses.
 2.  The only IO addresses usage is for "system memory space" mapping code in:
      drivers/acpi/acpica/exregion.c
      drivers/acpi/acpica/evrgnini.c
      drivers/acpi/acpica/exregion.c
    The mapped address is accessed in the handler of "system memory space"
    - acpi_ex_system_memory_space_handler().  This function in fact can be
    changed to invoke acpi_os_read/write_memory() so that __iomem can
    always be type-casted in the OSL layer.

According to the above investigation, we drew the following conclusion:
It is not a good idea to introduce __iomem address space awareness into
ACPICA mostly in order to protect non-IO addresses.

We can simply remove __iomem for acpi_os_map/unmap_memory() to remove
__iomem checker for ACPICA code. Then we need to enforce external usages
to invoke other APIs that are aware of __iomem address space.
The external usages are:
 drivers/acpi/apei/einj.c
 drivers/acpi/acpi_extlog.c
 drivers/char/tpm/tpm_acpi.c
 drivers/acpi/nvs.c

This patch thus performs cleanups in this way:
 1. Add acpi_os_map/unmap_iomem() to be invoked by non-ACPICA code.
 2. Remove __iomem from acpi_os_map/unmap_memory().

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 18:13:08 +02:00
Lv Zheng
a94e88cdd8 ACPICA: Tables: Avoid SSDT installation with acpi_gbl_disable_ssdt_table_load.
It is reported that when acpi_gbl_disable_ssdt_table_load is specified, user
still can see it installed into /sys/firmware/acpi/tables on Linux boxes.
This is because the option only stops table "loading", but doesn't stop
table "installing", thus it is still in the acpi_gbl_root_table_list. With
previous cleanups, it is possible to prevent SSDT installations to make
it not such confusing.  The global variable is also renamed.  Lv Zheng.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[rjw: Subject]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-20 22:59:39 +02:00
jhbird.choi@samsung.com
2d0acb4af9 ACPI: Clean up memory allocations
Use acpi_os_allocate_zeroed instead of acpi_os_allocate + memset.

Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-04 16:23:33 +02:00
Rafael J. Wysocki
08476907ab Merge branch 'acpica'
* acpica:
  ACPICA: Enable auto-serialization as a default kernel behavior.
  ACPICA: Ignore sync_level for methods that have been auto-serialized.
  ACPICA: Add additional named objects for the auto-serialize method scan.
  ACPICA: Add auto-serialization support for ill-behaved control methods.
  ACPICA: Remove global option to serialize all control methods.
2014-04-01 22:09:26 +02:00
Lv Zheng
08e1d7c029 ACPICA: Enable auto-serialization as a default kernel behavior.
The previous commit "ACPICA: Add auto-serialization support for ill-behaved
control methods" introduced the auto-serialization facility as a workaround
that can be enabled by "acpi_auto_serialize":

This feature marks control methods that create named objects as "serialized"
to avoid unwanted AE_ALREADY_EXISTS control method evaluation failures.

Enable method auto-serialization as the default kernel behavior.  The new kernel
parameter is also changed from "acpi_auto_serialize" to "acpi_no_auto_serialize"
to reflect the default behavior.

References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
References: http://www.spinics.net/lists/linux-acpi/msg49496.html
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-26 16:26:00 +01:00
Bob Moore
22b5afce6a ACPICA: Add auto-serialization support for ill-behaved control methods.
This change adds support to automatically mark a control method as
"serialized" if the method creates any named objects. This will
positively prevent the method from being entered by more than one
thread and thus preventing a possible abort when an attempt is
made to create an object twice.

Implemented by parsing all non-serialize control methods at table
load time.

This feature is disabled by default and this patch also adds a new
Linux kernel parameter "acpi_auto_serialize" to allow this feature
to be turned on for a specific boot.

References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-26 16:25:59 +01:00
Lv Zheng
e2b8ddcc6b ACPICA: Remove global option to serialize all control methods.
According to the reports, the "acpi_serialize" mechanism is broken as:

 A. The parallel method calls can still happen when the interpreter lock is
    released under the following conditions:
    1. External callbacks are invoked, for example, by the region handlers,
       the exception handlers, etc.;
    2. Module level execution is performed when Load/LoadTable opcodes are
       executed, and
    3. The _REG control methods are invoked to complete the region
       registrations.
 B. For the following situations, the interpreter lock need to be released
    even for a serialized method while currently, the lock-releasing
    operation is marked as a no-op by
    acpi_ex_relinquish/reacquire_interpreter() when this mechanism is
    enabled:
    1. Wait opcode is executed,
    2. Acquire opcode is executed, and
    3. Sleep opcode is executed.

This patch removes this mechanism and the internal
acpi_ex_relinquish/reacquire_interpreter() APIs.  Lv Zheng.

References: https://bugzilla.kernel.org/show_bug.cgi?id=52191
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-26 16:25:59 +01:00
Rafael J. Wysocki
6ac4a2ab16 Merge branch 'acpica'
* acpica: (29 commits)
  ACPICA: Revert "Headers: Deploy #pragma pack (push) and (pop)."
  ACPICA: Update version to 20140214.
  ACPICA: Prevent infinite loops when traversing corrupted lists.
  ACPICA: Debugger: Add missing objects; Traverse linked lists
  ACPICA: Add text: ACPICA policy for new _OSI strings. No functional change.
  ACPICA: Update for _PRP predefined name.
  ACPICA: Cleanup/improve global variable declarations.
  ACPICA: Comment update - no functional change.
  ACPICA: Do not abort _PRT repair on a single subpackage failure.
  ACPICA: Harden _PRT repair code; check for minimum package length.
  ACPICA: Restore code that repairs NULL package elements in return values.
  ACPICA: Properly handle NULL entries in _PRT return packages.
  ACPICA: Update conditional compilation flags for resource dump functions.
  ACPICA: Predefined names: Add support for the _PRP method.
  ACPICA: Headers: Deploy #pragma pack (push) and (pop).
  ACPICA: Add boot option to disable auto return object repair
  ACPICA: acpidump: Remove integer types translation protection.
  ACPICA: acpidump: Add sparse declarators support.
  ACPICA: Add "Windows 2013" string to _OSI support.
  ACPICA: Update version to 20140114.
  ...
2014-03-20 13:25:02 +01:00
Rafael J. Wysocki
e25c5abf41 Merge branches 'acpi-cleanup', 'acpi-thermal', 'acpi-pci', 'acpi-lpss' and 'acpi-button'
* acpi-cleanup:
  ACPI: Remove duplicate definitions of PREFIX
  ACPI / tables: Replace printk with pr_*

* acpi-thermal:
  ACPI / thermal: make acpi_thermal_check asynchronous on resume

* acpi-pci:
  ACPI / PCI: Do not call ISA-specific code if ISA is not supported

* acpi-lpss:
  ACPI / LPSS: Add Intel BayTrail ACPI mode PWM

* acpi-button:
  ACPI / button: Add ACPI Button event via netlink routine
2014-03-20 13:20:47 +01:00
Hanjun Guo
07070e12cf ACPI: Remove duplicate definitions of PREFIX
We already have a macro for PREFIX of "ACPI: " in
drivers/acpi/internal.h, so remove the duplicate ones
in ACPI drivers when internal.h is included.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-19 02:01:57 +01:00
Rafael J. Wysocki
1e3bcb596c ACPI / hotplug: Rework deferred execution of acpi_device_hotplug()
Since the only function executed by acpi_hotplug_execute() is
acpi_device_hotplug() and it only is called by the ACPI core,
simplify its definition so that it only takes two arguments, the
ACPI device object pointer and event code, rename it to
acpi_hotplug_schedule() and move its header from acpi_bus.h to
the ACPI core's internal header file internal.h.  Modify the
definition of acpi_device_hotplug() so that its first argument is
an ACPI device object pointer and modify the definition of
struct acpi_hp_work accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2014-03-05 01:26:35 +01:00
Lv Zheng
4dde507fc1 ACPICA: Add boot option to disable auto return object repair
Sometimes, there might be bugs caused by unexpected AML which is compliant
to the Windows but not compliant to the Linux implementation.

There is a predefined validation mechanism implemented in ACPICA to repair
the unexpected AML evaluation results that are caused by the unexpected
AMLs.  For example, BIOS may return misorder _CST result and the repair
mechanism can make an ascending order on the returned _CST package object
based on the C-state type.
This mechanism is quite useful to implement an AML interpreter with better
compliance with the real world where Windows is the de-facto standard and
BIOS codes are only tested on one platform thus not compliant to the
ACPI specification.

But if a compliance issue hasn't been figured out yet, it will be
difficult for developers to identify if the unexpected evaluation result
is caused by this mechanism or by the AML interpreter.
For example, _PR0 is expected to be a control method, but BIOS may use
Package: "Name(_PR0, Package(1) {P1PR})".
This boot option can disable the predefined validation mechanism so that
developers can make sure the root cause comes from the parser/executer.

This patch adds a new kernel parameter to disable this feature.

A build test has been made on a Dell Inspiron mini 1100 (i386 z530)
machine when this patch is applied and the corresponding boot test is
performed w/ or w/o the new kernel parameter specified.

References: https://bugzilla.kernel.org/show_bug.cgi?id=67901
Tested-by: Fabian Wehning <fabian.wehning@googlemail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-13 16:25:16 +01:00
Rafael J. Wysocki
25d412d932 Merge branch 'acpi-hotplug'
* acpi-hotplug:
  ACPI / scan: ACPI device object sysfs attribute for _STA evaluation
  ACPI / hotplug / driver core: Handle containers in a special way
  ACPI / hotplug: Add demand_offline hotplug profile flag
  ACPI / bind: Move acpi_get_child() to drivers/ide/ide-acpi.c
  ACPI / bind: Pass struct acpi_device pointer to acpi_bind_one()
  ACPI / bind: Rework struct acpi_bus_type
  ACPI / bind: Redefine acpi_preset_companion()
  ACPI / bind: Redefine acpi_get_child()
  PCI / ACPI: Use acpi_find_child_device() for child devices lookup
  ACPI / bind: Simplify child device lookups
  ACPI / scan: Use direct recurrence for device hierarchy walks
  ACPI: Introduce acpi_set_device_status()
  ACPI / hotplug: Drop unfinished global notification handling routines
  ACPI / hotplug: Rework generic code to handle suprise removals
  ACPI / hotplug: Move container-specific code out of the core
  ACPI / hotplug: Make ACPI PCI root hotplug use common hotplug code
  ACPI / hotplug: Introduce common hotplug function acpi_device_hotplug()
  ACPI / hotplug: Do not fail bus and device checks for disabled hotplug
  ACPI / scan: Add acpi_device objects for all device nodes in the namespace
  ACPI / scan: Define non-empty device removal handler
2014-01-12 23:45:04 +01:00
Rashika
66e162b393 ACPI / OSL: Mark the function acpi_table_checksum() as static
Marks the function acpi_table_checksum() as static in osl.c
because it is not used outside this file.

This eliminates the following warning in osl.c:
drivers/acpi/osl.c:547:11: warning: no previous prototype for
‘acpi_table_checksum’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-06 00:13:22 +01:00
Al Stone
cad1525a5e ACPI: remove trailing whitespace
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>
2013-12-07 01:27:56 +01:00
Lv Zheng
27d50c8271 ACPI / i915: Fix incorrect <acpi/acpi.h> inclusions via <linux/acpi_io.h>
To avoid build problems and breaking dependencies between ACPI header
files, <acpi/acpi.h> should not be included directly by code outside
of the ACPI core subsystem.  However, that is possible if
<linux/acpi_io.h> is included, because that file contains
a direct inclusion of <acpi/acpi.h>.

For this reason, remove the direct <acpi/acpi.h> inclusion from
<linux/acpi_io.h>, move that file from include/linux/ to include/acpi/
and make <linux/acpi.h> include it for CONFIG_ACPI set along with the
other ACPI header files.  Accordingly, Remove the inclusions of
<linux/acpi_io.h> from everywhere.

Of course, that causes the contents of the new <acpi/acpi_io.h> file
to be available for CONFIG_ACPI set only, so intel_opregion.o that
depends on it should also depend on CONFIG_ACPI (and it really should
not be compiled for CONFIG_ACPI unset anyway).

References: https://01.org/linuxgraphics/sites/default/files/documentation/acpi_igd_opregion_spec.pdf
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-07 01:24:33 +01:00
Rafael J. Wysocki
9ccad66f01 Merge branch 'acpi-cleanup' into acpi-hotplug
Conflicts:
	drivers/acpi/scan.c
2013-12-07 01:05:17 +01:00
Lv Zheng
8b48463f89 ACPI: Clean up inclusions of ACPI header files
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>
2013-12-07 01:03:14 +01:00
Rafael J. Wysocki
d783156ea3 ACPI / scan: Define non-empty device removal handler
If an ACPI namespace node is removed (usually, as a result of a
table unload), and there is a data object attached to that node,
acpi_ns_delete_node() executes the removal handler submitted to
acpi_attach_data() for that object.  That handler is currently empty
for struct acpi_device objects, so it is necessary to detach those
objects from the corresponding ACPI namespace nodes in advance every
time a table unload may happen.  That is cumbersome and inefficient
and leads to some design constraints that turn out to be quite
inconvenient (in particular, struct acpi_device objects cannot be
registered for namespace nodes representing devices that are not
reported as present or functional by _STA).

For this reason, introduce a non-empty removal handler for ACPI
device objects that will unregister them when their ACPI namespace
nodes go away.

This code modification alone should not change functionality except
for the ordering of the ACPI hotplug workqueue which should not
matter (without subsequent code changes).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:52:12 +01:00
Rafael J. Wysocki
63ff4d0765 Merge branch 'acpi-hotplug'
* acpi-hotplug:
  ACPI / hotplug: Consolidate deferred execution of ACPI hotplug routines
  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

Conflicts:
	include/acpi/acpiosxf.h (with the 'acpica' branch)
2013-11-07 19:31:15 +01:00
Rafael J. Wysocki
7b98118aaa ACPI / hotplug: Consolidate deferred execution of ACPI hotplug routines
There are two different interfaces for queuing up work items on the
ACPI hotplug workqueue, alloc_acpi_hp_work() used by PCI and PCI host
bridge hotplug code and acpi_os_hotplug_execute() used by the common
ACPI hotplug code and docking stations.  They both are somewhat
cumbersome to use and work slightly differently.

The users of alloc_acpi_hp_work() have to submit a work function that
will extract the necessary data items from a struct acpi_hp_work
object allocated by alloc_acpi_hp_work() and then will free that
object, while it would be more straightforward to simply use a work
function with one more argument and let the interface take care of
the execution details.

The users of acpi_os_hotplug_execute() also have to deal with the
fact that it takes only one argument in addition to the work function
pointer, although acpi_os_execute_deferred() actually takes care of
the allocation and freeing of memory, so it would have been able to
pass more arguments to the work function if it hadn't been
constrained by the connection with acpi_os_execute().

Moreover, while alloc_acpi_hp_work() makes GFP_KERNEL memory
allocations, which is correct, because hotplug work items are
always queued up from process context, acpi_os_hotplug_execute()
uses GFP_ATOMIC, as that is needed by acpi_os_execute().  Also,
acpi_os_execute_deferred() queued up by it waits for the ACPI event
workqueues to flush before executing the work function, whereas
alloc_acpi_hp_work() can't do anything similar.  That leads to
somewhat arbitrary differences in behavior between various ACPI
hotplug code paths and has to be straightened up.

For this reason, replace both alloc_acpi_hp_work() and
acpi_os_hotplug_execute() with a single interface,
acpi_hotplug_execute(), combining their behavior and being more
friendly to its users than any of the two.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-07 19:28:48 +01:00
Rafael J. Wysocki
5171f4fa74 Merge branch 'acpi-assorted'
* acpi-assorted:
  ACPI: Add Toshiba NB100 to Vista _OSI blacklist
  ACPI / osl: remove an unneeded NULL check
  ACPI / platform: add ACPI ID for a Broadcom GPS chip
  ACPI: improve acpi_extract_package() utility
  ACPI / LPSS: fix UART Auto Flow Control
  ACPI / platform: Add ACPI IDs for Intel SST audio device
  x86 / ACPI: fix incorrect placement of __initdata tag
  ACPI / thermal: convert printk(LEVEL...) to pr_<lvl>
  ACPI / sysfs: make GPE sysfs attributes only accept correct values
  ACPI / EC: Convert all printk() calls to dynamic debug function
  ACPI / button: Using input_set_capability() to mark device's event capability
  ACPI / osl: implement acpi_os_sleep() with msleep()
2013-10-28 01:20:24 +01:00
Dan Carpenter
5e2be4e0ed ACPI / osl: remove an unneeded NULL check
"str" is never NULL here so I have removed the check.  There are static
checkers which complain about superfluous NULL checks because it may
indicate confusion or a bug.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-18 13:38:37 +02:00
Liu Chuansheng
302822996f ACPI / osl: implement acpi_os_sleep() with msleep()
Currently, acpi_os_sleep() uses schedule_timeout_interruptible()
which can be interrupted by a signal, and that causes the real sleep
time to be shorter.

According to the ACPI spec:

 The Sleep term is used to implement long-term timing requirements.
 Execution is delayed for at least the required number of milliseconds.

The sleeping time should be at least the required number msecs, so use
msleep() which guarantees that to implement it.

Signed-off-by: Liu Chuansheng <chuansheng.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-25 17:08:12 +02:00
Yinghai Lu
bee7f9c83e ACPI / x86: Increase override tables number limit
Current ACPI tables in initrd is limited to 10, that is too small.
64 should be good enough as we have 35 sigs and could have several
SSDT.

Two problems in current code prevent us from increasing limit:
 1. The cpio file info array is put in stack, as every element is 32
    bytes, could run out of stack if we have that array size to 64.
    We can move it out from stack, make it global and put it into the
    __initdata section.
 2. early_ioremap() only can remap 256k one time. Current code maps
    10 tables at a time. If we increased that limit, the whole size
    could be more than 256k, so early_ioremap() would fail with that.
    We can map chunks one by one during copying, instead of mapping
    all of them together.

Signed-off-by: Yinghai <yinghai@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Thomas Renninger <trenn@suse.de>
Reviewed-by: Tang Chen <tangchen@cn.fujitsu.com>
Tested-by: Tang Chen <tangchen@cn.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-25 16:59:39 +02:00
Rafael J. Wysocki
0c581415b5 Merge branch 'acpi-assorted'
* acpi-assorted:
  ACPI / osl: Kill macro INVALID_TABLE().
  earlycpio.c: Fix the confusing comment of find_cpio_data().
  ACPI / x86: Print Hot-Pluggable Field in SRAT.
  ACPI / thermal: Use THERMAL_TRIPS_NONE macro to replace number
  ACPI / thermal: Remove unused macros in the driver/acpi/thermal.c
  ACPI / thermal: Remove the unused lock of struct acpi_thermal
  ACPI / osl: Fix osi_setup_entries[] __initdata attribute location
  ACPI / numa: Fix __init attribute location in slit_valid()
  ACPI / dock: Fix __init attribute location in find_dock_and_bay()
  ACPI / Sleep: Fix incorrect placement of __initdata
  ACPI / processor: Fix incorrect placement of __initdata
  ACPI / EC: Fix incorrect placement of __initdata
  ACPI / scan: Drop unnecessary label from acpi_create_platform_device()
  ACPI: Move acpi_bus_get_device() from bus.c to scan.c
  ACPI / scan: Allow platform device creation without any IO resources
  ACPI: Cleanup sparse warning on acpi_os_initialize1()
  platform / thinkpad: Remove deprecated hotkey_report_mode parameter
  ACPI: Remove the old /proc/acpi/event interface
2013-08-27 01:29:04 +02:00
Rafael J. Wysocki
afdca01c98 Merge branch 'acpica'
* acpica:
  ACPICA: Update version to 20130725.
  ACPICA: Update names for walk_namespace callbacks to clarify usage.
  ACPICA: Return error if DerefOf resolves to a null package element.
  ACPICA: Make ACPI Power Management Timer (PM Timer) optional.
  ACPICA: Fix divergences of the commit - ACPICA: Expose OSI version.
  ACPICA: Fix possible fault for methods that optionally have no return value.
  ACPICA: DeRefOf operator: Update to fully resolve FieldUnit and BufferField refs.
  ACPICA: Emit all unresolved method externals in a text block
  ACPICA: Export acpi_tb_validate_rsdp().
  ACPI: Add facility to remove all _OSI strings
  ACPI: Add facility to disable all _OSI OS vendor strings
  ACPICA: Add acpi_update_interfaces() public interface
  ACPICA: Update version to 20130626
  ACPICA: Fix compiler warnings for casting issues (only some compilers)
  ACPICA: Remove restriction of 256 maximum GPEs in any GPE block
  ACPICA: Disassembler: Expand maximum output string length to 64K
  ACPICA: TableManager: Export acpi_tb_scan_memory_for_rsdp()
  ACPICA: Update comments about behavior when _STA does not exist
2013-08-27 01:28:48 +02:00
Tang Chen
7702ae0dd9 ACPI / osl: Kill macro INVALID_TABLE().
The macro INVALID_TABLE() is defined like this:

 #define INVALID_TABLE(x, path, name)                                    \
         { pr_err("ACPI OVERRIDE: " x " [%s%s]\n", path, name); continue; }

And it is used like this:

	for (...) {
		...
		if (...)
			INVALID_TABLE()
		...
	}

The "continue" in the macro makes the code hard to understand.

And also, this macro is only used several times in a single file.
As suggested by Joe Perches <joe@perches.com>, we can remote it and
use pr_err directly.

So after this patch, this macro is removed, and pr_err() is used
like this:

	for (...) {
		...
		if (...) {
			pr_err("ACPI OVERRIDE: ......");
			continue;
		}
		...
	}

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Suggested-by: Joe Perches <joe@perches.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14 23:24:01 +02:00
Hanjun Guo
e73d313635 ACPI / osl: Fix osi_setup_entries[] __initdata attribute location
__initdata should come after the variable name being declared and
nowhere else, in this way the variable will be placed in the
intended section.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-13 12:37:16 +02:00
Ben Guthro
d6b47b1224 ACPI / sleep: Introduce acpi_os_prepare_extended_sleep() for extended sleep path
Like acpi_os_prepare_sleep(), register a callback for use in systems
like tboot, and xen, which have system specific requirements outside
of ACPICA.  This mirrors the functionality in acpi_os_prepare_sleep(),
called from acpi_hw_sleep()

Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-31 14:20:39 +02:00
Lv Zheng
1129c92faa ACPI: Cleanup sparse warning on acpi_os_initialize1()
This patch cleans up the following sparse warning:

# make C=2 drivers/acpi/osl.o
...
drivers/acpi/osl.c:1775:20: warning: symbol 'acpi_os_initialize1' was not declared. Should it be static?
...
  CC      drivers/acpi/osl.o

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-26 00:36:00 +02:00
Lv Zheng
741d81280a ACPI: Add facility to remove all _OSI strings
This patch changes the "acpi_osi=" boot parameter implementation so
that:
1. "acpi_osi=!" can be used to disable all _OSI OS vendor strings by
   default.  It is meaningless to specify "acpi_osi=!" multiple
   times as it can only affect the default state of the target _OSI
   strings.
2. "acpi_osi=!*" can be used to remove all _OSI OS vendor strings
   and all _OSI feature group strings.  It is useful to specify
   "acpi_osi=!*" multiple times through kernel command line to
   override the current state of the target _OSI strings.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-23 04:07:04 +02:00
Lv Zheng
5dc17986fd ACPI: Add facility to disable all _OSI OS vendor strings
This patch introduces "acpi_osi=!" command line to force Linux replying
"UNSUPPORTED" to all of the _OSI strings.  This patch is based on an
ACPICA enhancement - the new API acpi_update_interfaces().

The _OSI object provides the platform with the ability to query OSPM
to determine the set of ACPI related interfaces, behaviors, or
features that the operating system supports.  The argument passed to
the _OSI is a string like the followings:
1. Feature Group String, examples include
   Module Device
   Processor Device
   3.0 _SCP Extensions
   Processor Aggregator Device
   ...
2. OS Vendor String, examples include
   Linux
   FreeBSD
   Windows
   ...

There are AML codes provided in the ACPI namespace written in the
following style to determine OSPM interfaces / features:
    Method(OSCK)
    {
        if (CondRefOf(_OSI, Local0))
        {
            if (\_OSI("Windows"))
            {
                Return (One)
            }
            if (\_OSI("Windows 2006"))
            {
                Return (Ones)
            }
            Return (Zero)
        }
        Return (Zero)
    }

There is a debugging facility implemented in Linux.  Users can pass
"acpi_osi=" boot parameters to the kernel to tune the _OSI evaluation
result so that certain AML codes can be executed.  Current
implementation includes:
1. 'acpi_osi=' - this makes CondRefOf(_OSI, Local0) TRUE
2. 'acpi_osi="Windows"' - this makes \_OSI("Windows") TRUE
3. 'acpi_osi="!Windows"' - this makes \_OSI("Windows") FALSE
The function to implement this feature is also used as a quirk mechanism
in the Linux ACPI subystem.

When _OSI is evaluatated by the AML codes, ACPICA replies "SUPPORTED"
to all Windows operating system vendor strings.  This is because
Windows operating systems return "SUPPORTED" if the argument to the
_OSI method specifies an earlier version of Windows.  Please refer to
the following MSDN document:

How to Identify the Windows Version in ACPI by Using _OSI
http://msdn.microsoft.com/en-us/library/hardware/gg463275.aspx

This adds difficulties when developers want to feed specific Windows
operating system vendor string to the BIOS codes for debugging
purpose, multiple acpi_osi="!xxx" have to be specified in the command
line to force Linux replying "UNSUPPORTED" to the Windows OS vendor
strings listed in the AML codes.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-23 04:06:56 +02:00
Rafael J. Wysocki
5c0b1b2003 Merge branch 'acpi-assorted'
* acpi-assorted:
  ACPI: implement acpi_os_get_timer() according the spec
2013-06-29 15:03:44 +02:00