[HaBo]

22. Boot parameter reference

   acpi=force
          If you built your kernel with acpi disabled, you can use this option
          to force its use.

   acpi=off
          If you built your kernel with ACPI enabled, you can use this option
          to turn it off (in case you'd rather use APM, it interferes with
          something else, or it's just plain broken).

   acpi=ht
          Enable ACPI only to the degree needed to support hyperthreading. If
          you  don't  want  to  use most of the ACPI driver, but you want
          hyperthreading working, use this option so that the ACPI tables will
          be used for virtual processor discovery.

   acpi=strict
          Be anal about syntax and method requirements in ACPI tables provided
          by the vendor; if you turn this on, you can find potential problems
          with your DSDT that may not show up by other means.

   acpi_sleep=s3_bios
          If this boot parameter is passed, upon wake from suspend, the kernel
          will  try  to  initialize your video adapter by calling code at
          c000:0003h. In practice, this code may no longer be available after
          power on, so your system may crash. But for some people, this is the
          only way to get suspend to RAM to work. Use with caution.

   acpi_sleep=s3_mode
          Upon wake from suspend, the kernel will set the video adapter mode to
          the mode it was in before suspend, using the VESA BIOS mode set call
          (0x4f02). Use this if your system can get back to VGA text mode from
          suspend, i.e. it suspends ok from a text console, but doesn't work
          from X. This could crash your system so use with caution.

   acpi_sleep=s3_bios,s3_mode
          On some systems that require acpi_sleep=s3_bios, the system will be
          left in VGA text mode and so you'll need to do s3_mode as well.

   acpi_sci=level|edge|high|low
          Set ACPI System Control Interrupt trigger mode; it's very unlikely
          that you'll need this, as SCI handling has been stable for some time.
          However, if you have a prerelease BIOS, and you see messages in your
          log about unrecognized SCIs, try using one of these settings. [If
          someone who has to use this option would contact me, I'll add a
          better description.]

   acpi_irq_balance
          ACPI  will balance active IRQs to minimize sharing. This is the
          default in APIC mode.

   acpi_irq_nobalance
          ACPI  will  not  move  active  IRQs  around  (the  opposite  of
          acpi_irq_balance). This is the default in PIC mode.

   acpi_irq_pci=...
          If you have set acpi_irq_balance, you have to reserve some IRQs for
          for use by PCI or else ACPI may use them all; list them here. Format:
          <irq>,<irq>...

   acpi_irq_isa
          If you have set acpi_irq_balance, you have to reserve some IRQs for
          for use by ISA or else ACPI may use them all; list them here. Don't
          do this unless you have ISA devices. Format: <irq>,<irq>...

   acpi_osi=
          By default, the _OSI method in ACPI will tell the BIOS that we are
          running Microsoft Windows NT. But if you use this option with an
          empty parameter, it disables the _OSI method. (What does the BIOS do
          then?)

   acpi_os_name=
          By default, the _OSI method in ACPI will tell the BIOS that we are
          running Microsoft Windows NT. But if you specify a name here, that OS
          name will be reported to the BIOS instead. This may enable or disable
          some methods in your DSDT depending on the OS string you choose.

   acpi_serialize
          If you see errors in your log which include things like

            Error: Looking up [some-device-id] in namespace, AE_ALREADY_EXISTS


          then try setting this option. It forces serialization of AML methods
          in  case  a method creates namespace objects, fails to complete
          cleanly, and leaves its debris around; this may allow us to track
          down the specific problem.

   acpi_skip_timer_override
          This option is specific to certain versions of the nForce2 BIOS which
          map IRQ0 to pin 2 and result in the timer being XT-PIC instead of
          IO-APIC-edge.  This  isn't really an ACPI issue but it's called
          acpi_skip_timer_override so it's in this document. See kernel bug
          1203 at [241]http://bugme.osdl.org/show_bug.cgi?id=1203 for more
          info.

   acpi_dbg_layer=
          Format: <int> ; Turn on or off debugging of a or several acpi debug
          layers. Each bit of the <int> indicates a separate layer. Starting
          from the rightmost bit, you can turn on debugging for the layers:
          UTILITIES, HARDWARE, EVENTS, TABLES, NAMESPACE, PARSER, DISPATCHER,
          EXECUTER, RESOURCES, CA_DEBUGGER, OS_SERVICES, CA_DISASSEMBLER,
          COMPILER, and TOOLS. If you don't do this at boot time you can still
          enable this by writing to /proc/acpi/debug_layer.

   acpi_dbg_level=
          Format: <int> ; Turn on or off debugging of a or several acpi debug
          levels. Each bit of the <int> indicates a separate level. Starting
          from the rightmost bit, you can turn on debugging for messages logged
          at the level: ERROR, WARN, INIT, DEBUG_OBJECT, INFO, INIT_NAMES,
          PARSE, LOAD, DISPATCH, EXEC, NAMES, OPREGION, BFIELD, TABLES, VALUES,
          OBJECTS, RESOURCES, USER_REQUESTS, PACKAGE, ALLOCATIONS, FUNCTIONS,
          OPTIMIZATIONS, MUTEX, THREADS, IO, INTERRUPTS, AML_DISASSEMBLE,
          VERBOSE_INFO, FULL_TABLES, and EVENTS. If you don't do this at boot
          time you can still enable this by writing to /proc/acpi/debug_level.

   ec_burst=
          use burst mode instead of polling mode for embedded controller; this
          mode is better in the long run than polling mode but not ready for
          prime time yet. Use it, however, if you see problems with button
          failure  or  battery  status  failure or other ACPI events just
          disappearing  and  not  being  handled;  see kernel bug 3851 at
          [242]http://bugzilla.kernel.org/show_bug.cgi?id=3851  for  more
          information.

   acpi_generic_hotkey
          There is a generic hotkey driver which will let you map hotkey codes
          to specific acpi methods. It's not at all user friendly. Nonetheless,
          it may be useful for you if your laptop has hotkeys that use the ACPI
          interface.  If  you compile in the generic hotkey driver, using
          CONFIG_ACPI_HOTKEY, you must use this boot option for the driver to
          be enabled.

          Some laptops have specific hotkey drivers for their setups; see the
          CONFIG options above for the list. If you set this option and you
          have compiled in both the generic hotkey driver and a specific driver
          for one of those laptops, only the generic hotkey driver will be
          used.

   acpi_fake_ecdt
          Workaround failure due to BIOS lacking ECDT; use this if you see
          errors  in  your log early on about the battery, adapter or the
          embedded controller. Setting this option lets the kernel ignore the
          missing ECDT, and come back to complete initialization of those
          devices later when it has pulled more complete information from the
          DSDT.

   acpi_wake_gpes_always_on
          If your system seems not to be generating ACPI events, try setting
          this option. Here's the explanation, taken right from the kernel
          code:

          Wake  and Run-Time GPES are expected to be separate. We disable
          wake-GPEs at run-time to prevent spurious interrupts. However, if a
          system exists that shares Wake and Run-time events on the same GPE
          this flag is available to tell Linux to keep the wake-time GPEs
          enabled at run-time.

   pci=noacpi
          Do not use ACPI for IRQ routing. ACPI looks at _PRT packages to
          figure out which interrupt goes with which PCI interrupt link device
          and then looks up the resources that device uses. Instead, use the
          PCI IRQ routing table. If your kernel hangs during boot, you may have
          serious IRQ problems; try this option.

   pci=routeirq
          Do  IRQ  routing  for  all PCI devices. Each device should call
          pci_enable_device(), which will do this IRQ routing, but some drivers
          may be broken and not call it, so this option makes sure it gets
          called for each device outside of the driver. If you have problems
          with a particular device, try this option. Someday this option should
          go away. I wonder about proprietary drivers though... Maybe this
          option is here to stay.

   pnpacpi=off
          Try this option if you are having trouble with PNP devices under
          ACPI; this will disable use of PNPACPI and will use PNPBIOS instead.

   processor.max_cstate
          Limit   processor   to   maximum   C-state;   if   you  enabled
          CONFIG_ACPI_PROCESSOR so that the CPU is placed in different power
          states when it is idle, you may want this. Various IBM Thinkpad
          systems emit a high-pitched whine when the CPU enters C3 or C4, so
          passing  C2  as a parameter will prevent that. See ThinkWiki at
          [243]http://www.thinkwiki.org/wiki/Problem_with_high_pitch_noisesto
          check your specific model.

          If  you don't want to lose the ability to use these lower power
          states, you can try adjusting your timer speed instead: set your
          default timer speed to HZ_100 (CONFIG_HZ_100).

          If you know that your system should support C3 or C4 and a look at
          /sys/module/processor/parameters/max_cstate shows that it's set
          lower, you can try to increase it. Some BIOSes are blacklisted from
          these lower power states in the kernel. As of this writing, those are
          the IBM ThinkPad R40e, the Medion 41700, and the Clevo 5600D. Set
          max_cstate=9 to override this limit.

2010-01-10 19:21:07,978 WARNING: modinfo for module wl failed: ERROR: modinfo: could not open /lib/modules/2.6.32-7-generic/updates/dkms/wl.ko: Invalid argument