Merge tag 'qcom-arm64-defconfig-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / Documentation / kernel-parameters.txt

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 0b3de80..82b42c9 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -131,6 +131,7 @@ parameter is applicable:
                        More X86-64 boot options can be found in
                        Documentation/x86/x86_64/boot-options.txt .
        X86     Either 32-bit or 64-bit x86 (same as X86-32+X86-64)
                        More X86-64 boot options can be found in
                        Documentation/x86/x86_64/boot-options.txt .
        X86     Either 32-bit or 64-bit x86 (same as X86-32+X86-64)

+       X86_UV  SGI UV support is enabled.

        XEN     Xen support is enabled
 
 In addition, the following text indicates that the option:
        XEN     Xen support is enabled
 
 In addition, the following text indicates that the option:


@@ -167,16 +168,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
        acpi=           [HW,ACPI,X86,ARM64]
                        Advanced Configuration and Power Interface
 
        acpi=           [HW,ACPI,X86,ARM64]
                        Advanced Configuration and Power Interface

-                       Format: { force | off | strict | noirq | rsdt |
+                       Format: { force | on | off | strict | noirq | rsdt |

                                  copy_dsdt }
                        force -- enable ACPI if default was off
                                  copy_dsdt }
                        force -- enable ACPI if default was off

+                       on -- enable ACPI but allow fallback to DT [arm64]

                        off -- disable ACPI if default was on
                        noirq -- do not use ACPI for IRQ routing
                        strict -- Be less tolerant of platforms that are not
                                strictly ACPI specification compliant.
                        rsdt -- prefer RSDT over (default) XSDT
                        copy_dsdt -- copy DSDT to memory
                        off -- disable ACPI if default was on
                        noirq -- do not use ACPI for IRQ routing
                        strict -- Be less tolerant of platforms that are not
                                strictly ACPI specification compliant.
                        rsdt -- prefer RSDT over (default) XSDT
                        copy_dsdt -- copy DSDT to memory

-                       For ARM64, ONLY "acpi=off" or "acpi=force" are available
+                       For ARM64, ONLY "acpi=off", "acpi=on" or "acpi=force"
+                       are available

 
                        See also Documentation/power/runtime_pm.txt, pci=noacpi
 
 
                        See also Documentation/power/runtime_pm.txt, pci=noacpi
 


@@ -312,6 +315,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        acpi_osi=!*             # remove all strings
                        acpi_osi=!              # disable all built-in OS vendor
                                                  strings
                        acpi_osi=!*             # remove all strings
                        acpi_osi=!              # disable all built-in OS vendor
                                                  strings

+                       acpi_osi=!!             # enable all built-in OS vendor
+                                                 strings

                        acpi_osi=               # disable all strings
 
                        'acpi_osi=!' can be used in combination with single or
                        acpi_osi=               # disable all strings
 
                        'acpi_osi=!' can be used in combination with single or


@@ -542,6 +547,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        Format: <int> (must be >=0)
                        Default: 64
 
                        Format: <int> (must be >=0)
                        Default: 64
 

+       bau=            [X86_UV] Enable the BAU on SGI UV.  The default
+                       behavior is to disable the BAU (i.e. bau=0).
+                       Format: { "0" | "1" }
+                       0 - Disable the BAU.
+                       1 - Enable the BAU.
+                       unset - Disable the BAU.
+

        baycom_epp=     [HW,AX25]
                        Format: <io>,<mode>
 
        baycom_epp=     [HW,AX25]
                        Format: <io>,<mode>
 


@@ -826,6 +838,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        It will be ignored when crashkernel=X,high is not used
                        or memory reserved is below 4G.
 
                        It will be ignored when crashkernel=X,high is not used
                        or memory reserved is below 4G.
 

+       cryptomgr.notests
+                        [KNL] Disable crypto self-tests
+

        cs89x0_dma=     [HW,NET]
                        Format: <dma>
 
        cs89x0_dma=     [HW,NET]
                        Format: <dma>
 


@@ -1039,6 +1054,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        the driver will use only 32-bit accessors to read/write
                        the device registers.
 
                        the driver will use only 32-bit accessors to read/write
                        the device registers.
 

+               meson,<addr>
+                       Start an early, polled-mode console on a meson serial
+                       port at the specified address. The serial port must
+                       already be setup and configured. Options are not yet
+                       supported.
+

                msm_serial,<addr>
                        Start an early, polled-mode console on an msm serial
                        port at the specified address. The serial port
                msm_serial,<addr>
                        Start an early, polled-mode console on an msm serial
                        port at the specified address. The serial port


@@ -1661,6 +1682,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                hwp_only
                        Only load intel_pstate on systems which support
                        hardware P state control (HWP) if available.
                hwp_only
                        Only load intel_pstate on systems which support
                        hardware P state control (HWP) if available.

+               support_acpi_ppc
+                       Enforce ACPI _PPC performance limits. If the Fixed ACPI
+                       Description Table, specifies preferred power management
+                       profile as "Enterprise Server" or "Performance Server",
+                       then this feature is turned on by default.

 
        intremap=       [X86-64, Intel-IOMMU]
                        on      enable Interrupt Remapping (default)
 
        intremap=       [X86-64, Intel-IOMMU]
                        on      enable Interrupt Remapping (default)


@@ -1767,6 +1793,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        PCI device 00:14.0 write the parameter as:
                                ivrs_hpet[0]=00:14.0
 
                        PCI device 00:14.0 write the parameter as:
                                ivrs_hpet[0]=00:14.0
 

+       ivrs_acpihid    [HW,X86_64]
+                       Provide an override to the ACPI-HID:UID<->DEVICE-ID
+                       mapping provided in the IVRS ACPI table. For
+                       example, to map UART-HID:UID AMD0020:0 to
+                       PCI device 00:14.5 write the parameter as:
+                               ivrs_acpihid[00:14.5]=AMD0020:0
+

        js=             [HW,JOY] Analog joystick
                        See Documentation/input/joystick.txt.
 
        js=             [HW,JOY] Analog joystick
                        See Documentation/input/joystick.txt.
 


@@ -2141,6 +2174,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        [KNL,SH] Allow user to override the default size for
                        per-device physically contiguous DMA buffers.
 
                        [KNL,SH] Allow user to override the default size for
                        per-device physically contiguous DMA buffers.
 

+        memhp_default_state=online/offline
+                       [KNL] Set the initial state for the memory hotplug
+                       onlining policy. If not specified, the default value is
+                       set according to the
+                       CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE kernel config
+                       option.
+                       See Documentation/memory-hotplug.txt.
+

        memmap=exactmap [KNL,X86] Enable setting of an exact
                        E820 memory map, as specified by the user.
                        Such memmap=exactmap lines can be constructed based on
        memmap=exactmap [KNL,X86] Enable setting of an exact
                        E820 memory map, as specified by the user.
                        Such memmap=exactmap lines can be constructed based on


@@ -2538,6 +2579,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
        nohugeiomap     [KNL,x86] Disable kernel huge I/O mappings.
 
 
        nohugeiomap     [KNL,x86] Disable kernel huge I/O mappings.
 

+       nosmt           [KNL,S390] Disable symmetric multithreading (SMT).
+                       Equivalent to smt=1.
+

        noxsave         [BUGS=X86] Disables x86 extended register state save
                        and restore using xsave. The kernel will fallback to
                        enabling legacy floating-point and sse state.
        noxsave         [BUGS=X86] Disables x86 extended register state save
                        and restore using xsave. The kernel will fallback to
                        enabling legacy floating-point and sse state.


@@ -2921,11 +2965,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                                for broken drivers that don't call it.
                skip_isa_align  [X86] do not align io start addr, so can
                                handle more pci cards
                                for broken drivers that don't call it.
                skip_isa_align  [X86] do not align io start addr, so can
                                handle more pci cards

-               firmware        [ARM] Do not re-enumerate the bus but instead
-                               just use the configuration from the
-                               bootloader. This is currently used on
-                               IXP2000 systems where the bus has to be
-                               configured a certain way for adjunct CPUs.

                noearly         [X86] Don't do any early type 1 scanning.
                                This might help on some broken boards which
                                machine check when some devices' config space
                noearly         [X86] Don't do any early type 1 scanning.
                                This might help on some broken boards which
                                machine check when some devices' config space


@@ -3284,6 +3323,44 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        Lazy RCU callbacks are those which RCU can
                        prove do nothing more than free memory.
 
                        Lazy RCU callbacks are those which RCU can
                        prove do nothing more than free memory.
 

+       rcuperf.gp_exp= [KNL]
+                       Measure performance of expedited synchronous
+                       grace-period primitives.
+
+       rcuperf.holdoff= [KNL]
+                       Set test-start holdoff period.  The purpose of
+                       this parameter is to delay the start of the
+                       test until boot completes in order to avoid
+                       interference.
+
+       rcuperf.nreaders= [KNL]
+                       Set number of RCU readers.  The value -1 selects
+                       N, where N is the number of CPUs.  A value
+                       "n" less than -1 selects N-n+1, where N is again
+                       the number of CPUs.  For example, -2 selects N
+                       (the number of CPUs), -3 selects N+1, and so on.
+                       A value of "n" less than or equal to -N selects
+                       a single reader.
+
+       rcuperf.nwriters= [KNL]
+                       Set number of RCU writers.  The values operate
+                       the same as for rcuperf.nreaders.
+                       N, where N is the number of CPUs
+
+       rcuperf.perf_runnable= [BOOT]
+                       Start rcuperf running at boot time.
+
+       rcuperf.shutdown= [KNL]
+                       Shut the system down after performance tests
+                       complete.  This is useful for hands-off automated
+                       testing.
+
+       rcuperf.perf_type= [KNL]
+                       Specify the RCU implementation to test.
+
+       rcuperf.verbose= [KNL]
+                       Enable additional printk() statements.
+

        rcutorture.cbflood_inter_holdoff= [KNL]
                        Set holdoff time (jiffies) between successive
                        callback-flood tests.
        rcutorture.cbflood_inter_holdoff= [KNL]
                        Set holdoff time (jiffies) between successive
                        callback-flood tests.


@@ -3695,6 +3772,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                                1: Fast pin select (default)
                                2: ATC IRMode
 
                                1: Fast pin select (default)
                                2: ATC IRMode
 

+       smt             [KNL,S390] Set the maximum number of threads (logical
+                       CPUs) to use per physical CPU on systems capable of
+                       symmetric multithreading (SMT). Will be capped to the
+                       actual hardware limit.
+                       Format: <integer>
+                       Default: -1 (no limit)
+

        softlockup_panic=
                        [KNL] Should the soft-lockup detector generate panics.
                        Format: <integer>
        softlockup_panic=
                        [KNL] Should the soft-lockup detector generate panics.
                        Format: <integer>