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-rw-r--r--Documentation/kernel-parameters.txt125
1 files changed, 96 insertions, 29 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index dd28a0d..343e0f0 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -101,6 +101,7 @@ parameter is applicable:
X86-64 X86-64 architecture is enabled.
More X86-64 boot options can be found in
Documentation/x86_64/boot-options.txt .
+ X86 Either 32bit or 64bit x86 (same as X86-32+X86-64)
In addition, the following text indicates that the option:
@@ -217,20 +218,47 @@ and is between 256 and 4096 characters. It is defined in the file
acpi.debug_level= [HW,ACPI]
Format: <int>
Each bit of the <int> indicates an ACPI debug level,
- 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_level.
- CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
- Available bits (add the numbers together) to enable different
- debug output levels of the ACPI subsystem:
- 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.
+ 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.
+
+ acpi.power_nocheck= [HW,ACPI]
+ Format: 1/0 enable/disable the check of power state.
+ On some bogus BIOS the _PSC object/_STA object of
+ power resource can't return the correct device power
+ state. In such case it is unneccessary to check its
+ power state again in power transition.
+ 1 : disable the power state check
acpi_pm_good [X86-32,X86-64]
Override the pmtimer bug detection: force the kernel
@@ -690,7 +718,7 @@ and is between 256 and 4096 characters. It is defined in the file
See Documentation/block/as-iosched.txt and
Documentation/block/deadline-iosched.txt for details.
- elfcorehdr= [X86-32, X86_64]
+ elfcorehdr= [IA64,PPC,SH,X86-32,X86_64]
Specifies physical address of start of kernel core
image elf header. Generally kexec loader will
pass this option to capture kernel.
@@ -796,6 +824,8 @@ and is between 256 and 4096 characters. It is defined in the file
Defaults to the default architecture's huge page size
if not specified.
+ hlt [BUGS=ARM,SH]
+
i8042.debug [HW] Toggle i8042 debug mode
i8042.direct [HW] Put keyboard port into non-translated mode
i8042.dumbkbd [HW] Pretend that controller can only read data from
@@ -1211,6 +1241,10 @@ and is between 256 and 4096 characters. It is defined in the file
mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
memory.
+ memchunk=nn[KMG]
+ [KNL,SH] Allow user to override the default size for
+ per-device physically contiguous DMA buffers.
+
memmap=exactmap [KNL,X86-32,X86_64] Enable setting of an exact
E820 memory map, as specified by the user.
Such memmap=exactmap lines can be constructed based on
@@ -1393,6 +1427,8 @@ and is between 256 and 4096 characters. It is defined in the file
nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
+ nodsp [SH] Disable hardware DSP at boot time.
+
noefi [X86-32,X86-64] Disable EFI runtime services support.
noexec [IA-64]
@@ -1409,13 +1445,15 @@ and is between 256 and 4096 characters. It is defined in the file
noexec32=off: disable non-executable mappings
read implies executable mappings
+ nofpu [SH] Disable hardware FPU at boot time.
+
nofxsr [BUGS=X86-32] Disables x86 floating point extended
register save and restore. The kernel will only save
legacy floating-point registers on task switch.
noclflush [BUGS=X86] Don't use the CLFLUSH instruction
- nohlt [BUGS=ARM]
+ nohlt [BUGS=ARM,SH]
no-hlt [BUGS=X86-32] Tells the kernel that the hlt
instruction doesn't work correctly and not to
@@ -1578,7 +1616,7 @@ and is between 256 and 4096 characters. It is defined in the file
See also Documentation/paride.txt.
pci=option[,option...] [PCI] various PCI subsystem options:
- off [X86-32] don't probe for the PCI bus
+ off [X86] don't probe for the PCI bus
bios [X86-32] force use of PCI BIOS, don't access
the hardware directly. Use this if your machine
has a non-standard PCI host bridge.
@@ -1586,9 +1624,9 @@ and is between 256 and 4096 characters. It is defined in the file
hardware access methods are allowed. Use this
if you experience crashes upon bootup and you
suspect they are caused by the BIOS.
- conf1 [X86-32] Force use of PCI Configuration
+ conf1 [X86] Force use of PCI Configuration
Mechanism 1.
- conf2 [X86-32] Force use of PCI Configuration
+ conf2 [X86] Force use of PCI Configuration
Mechanism 2.
noaer [PCIE] If the PCIEAER kernel config parameter is
enabled, this kernel boot option can be used to
@@ -1608,37 +1646,37 @@ and is between 256 and 4096 characters. It is defined in the file
this option if the kernel is unable to allocate
IRQs or discover secondary PCI buses on your
motherboard.
- rom [X86-32] Assign address space to expansion ROMs.
+ rom [X86] Assign address space to expansion ROMs.
Use with caution as certain devices share
address decoders between ROMs and other
resources.
- norom [X86-32,X86_64] Do not assign address space to
+ norom [X86] Do not assign address space to
expansion ROMs that do not already have
BIOS assigned address ranges.
- irqmask=0xMMMM [X86-32] Set a bit mask of IRQs allowed to be
+ irqmask=0xMMMM [X86] Set a bit mask of IRQs allowed to be
assigned automatically to PCI devices. You can
make the kernel exclude IRQs of your ISA cards
this way.
- pirqaddr=0xAAAAA [X86-32] Specify the physical address
+ pirqaddr=0xAAAAA [X86] Specify the physical address
of the PIRQ table (normally generated
by the BIOS) if it is outside the
F0000h-100000h range.
- lastbus=N [X86-32] Scan all buses thru bus #N. Can be
+ lastbus=N [X86] Scan all buses thru bus #N. Can be
useful if the kernel is unable to find your
secondary buses and you want to tell it
explicitly which ones they are.
- assign-busses [X86-32] Always assign all PCI bus
+ assign-busses [X86] Always assign all PCI bus
numbers ourselves, overriding
whatever the firmware may have done.
- usepirqmask [X86-32] Honor the possible IRQ mask stored
+ usepirqmask [X86] Honor the possible IRQ mask stored
in the BIOS $PIR table. This is needed on
some systems with broken BIOSes, notably
some HP Pavilion N5400 and Omnibook XE3
notebooks. This will have no effect if ACPI
IRQ routing is enabled.
- noacpi [X86-32] Do not use ACPI for IRQ routing
+ noacpi [X86] Do not use ACPI for IRQ routing
or for PCI scanning.
- use_crs [X86-32] Use _CRS for PCI resource
+ use_crs [X86] Use _CRS for PCI resource
allocation.
routeirq Do IRQ routing for all PCI devices.
This is normally done in pci_enable_device(),
@@ -1667,6 +1705,12 @@ and is between 256 and 4096 characters. It is defined in the file
reserved for the CardBus bridge's memory
window. The default value is 64 megabytes.
+ pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
+ Management.
+ off Disable ASPM.
+ force Enable ASPM even on devices that claim not to support it.
+ WARNING: Forcing ASPM on may cause system lockups.
+
pcmv= [HW,PCMCIA] BadgePAD 4
pd. [PARIDE]
@@ -1694,6 +1738,10 @@ and is between 256 and 4096 characters. It is defined in the file
Override pmtimer IOPort with a hex value.
e.g. pmtmr=0x508
+ pnp.debug [PNP]
+ Enable PNP debug messages. This depends on the
+ CONFIG_PNP_DEBUG_MESSAGES option.
+
pnpacpi= [ACPI]
{ off }
@@ -2191,7 +2239,7 @@ and is between 256 and 4096 characters. It is defined in the file
thermal.crt= [HW,ACPI]
-1: disable all critical trip points in all thermal zones
- <degrees C>: lower all critical trip points
+ <degrees C>: override all critical trip points
thermal.nocrt= [HW,ACPI]
Set to disable actions on ACPI thermal zone
@@ -2253,6 +2301,25 @@ and is between 256 and 4096 characters. It is defined in the file
autosuspended. Devices for which the delay is set
to a negative value won't be autosuspended at all.
+ usbcore.usbfs_snoop=
+ [USB] Set to log all usbfs traffic (default 0 = off).
+
+ usbcore.blinkenlights=
+ [USB] Set to cycle leds on hubs (default 0 = off).
+
+ usbcore.old_scheme_first=
+ [USB] Start with the old device initialization
+ scheme (default 0 = off).
+
+ usbcore.use_both_schemes=
+ [USB] Try the other device initialization scheme
+ if the first one fails (default 1 = enabled).
+
+ usbcore.initial_descriptor_timeout=
+ [USB] Specifies timeout for the initial 64-byte
+ USB_REQ_GET_DESCRIPTOR request in milliseconds
+ (default 5000 = 5.0 seconds).
+
usbhid.mousepoll=
[USBHID] The interval which mice are to be polled at.