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-rw-r--r--Documentation/kernel-parameters.txt97
1 files changed, 40 insertions, 57 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 784443acca9c..b3b82f92f1dd 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -198,59 +198,42 @@ and is between 256 and 4096 characters. It is defined in the file
that require a timer override, but don't have
HPET
- acpi.debug_layer= [HW,ACPI]
+ acpi_backlight= [HW,ACPI]
+ acpi_backlight=vendor
+ acpi_backlight=video
+ If set to vendor, prefer vendor specific driver
+ (e.g. thinkpad_acpi, sony_acpi, etc.) instead
+ of the ACPI video.ko driver.
+
+ acpi_display_output= [HW,ACPI]
+ acpi_display_output=vendor
+ acpi_display_output=video
+ See above.
+
+ acpi.debug_layer= [HW,ACPI,ACPI_DEBUG]
+ acpi.debug_level= [HW,ACPI,ACPI_DEBUG]
Format: <int>
- Each bit of the <int> indicates an ACPI debug layer,
- 1: enable, 0: disable. It is useful for boot time
- debugging. After system has booted up, it can be set
- via /sys/module/acpi/parameters/debug_layer.
- CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
- Available bits (add the numbers together) to enable debug output
- for specific parts of the ACPI subsystem:
- 0x01 utilities 0x02 hardware 0x04 events 0x08 tables
- 0x10 namespace 0x20 parser 0x40 dispatcher
- 0x80 executer 0x100 resources 0x200 acpica debugger
- 0x400 os services 0x800 acpica disassembler.
- The number can be in decimal or prefixed with 0x in hex.
- Warning: Many of these options can produce a lot of
- output and make your system unusable. Be very careful.
-
- acpi.debug_level= [HW,ACPI]
- Format: <int>
- Each bit of the <int> indicates an ACPI debug level,
- which corresponds to the level in an ACPI_DEBUG_PRINT
- statement. After system has booted up, this mask
- can be set via /sys/module/acpi/parameters/debug_level.
-
- CONFIG_ACPI_DEBUG must be enabled for this to produce
- any output. The number can be in decimal or prefixed
- with 0x in hex. Some of these options produce so much
- output that the system is unusable.
-
- The following global components are defined by the
- ACPI CA:
- 0x01 error
- 0x02 warn
- 0x04 init
- 0x08 debug object
- 0x10 info
- 0x20 init names
- 0x40 parse
- 0x80 load
- 0x100 dispatch
- 0x200 execute
- 0x400 names
- 0x800 operation region
- 0x1000 bfield
- 0x2000 tables
- 0x4000 values
- 0x8000 objects
- 0x10000 resources
- 0x20000 user requests
- 0x40000 package
- The number can be in decimal or prefixed with 0x in hex.
- Warning: Many of these options can produce a lot of
- output and make your system unusable. Be very careful.
+ CONFIG_ACPI_DEBUG must be enabled to produce any ACPI
+ debug output. Bits in debug_layer correspond to a
+ _COMPONENT in an ACPI source file, e.g.,
+ #define _COMPONENT ACPI_PCI_COMPONENT
+ Bits in debug_level correspond to a level in
+ ACPI_DEBUG_PRINT statements, e.g.,
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, ...
+ See Documentation/acpi/debug.txt for more information
+ about debug layers and levels.
+
+ Enable AML "Debug" output, i.e., stores to the Debug
+ object while interpreting AML:
+ acpi.debug_layer=0xffffffff acpi.debug_level=0x2
+ Enable PCI/PCI interrupt routing info messages:
+ acpi.debug_layer=0x400000 acpi.debug_level=0x4
+ Enable all messages related to ACPI hardware:
+ acpi.debug_layer=0x2 acpi.debug_level=0xffffffff
+
+ Some values produce so much output that the system is
+ unusable. The "log_buf_len" parameter may be useful
+ if you need to capture more output.
acpi.power_nocheck= [HW,ACPI]
Format: 1/0 enable/disable the check of power state.
@@ -995,13 +978,15 @@ and is between 256 and 4096 characters. It is defined in the file
Format:
<cpu number>,...,<cpu number>
or
- <cpu number>-<cpu number> (must be a positive range in ascending order)
+ <cpu number>-<cpu number>
+ (must be a positive range in ascending order)
or a mixture
<cpu number>,...,<cpu number>-<cpu number>
+
This option can be used to specify one or more CPUs
to isolate from the general SMP balancing and scheduling
- algorithms. The only way to move a process onto or off
- an "isolated" CPU is via the CPU affinity syscalls.
+ algorithms. You can move a process onto or off an
+ "isolated" CPU via the CPU affinity syscalls or cpuset.
<cpu number> begins at 0 and the maximum value is
"number of CPUs in system - 1".
@@ -1474,8 +1459,6 @@ and is between 256 and 4096 characters. It is defined in the file
Valid arguments: on, off
Default: on
- noirqbalance [X86-32,SMP,KNL] Disable kernel irq balancing
-
noirqdebug [X86-32] Disables the code which attempts to detect and
disable unhandled interrupt sources.
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