License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
|
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# SPDX-License-Identifier: GPL-2.0
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2005-04-17 06:20:36 +08:00
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#
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# ACPI Configuration
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#
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2018-08-22 04:37:33 +08:00
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config ARCH_SUPPORTS_ACPI
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bool
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2007-07-03 13:40:59 +08:00
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menuconfig ACPI
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2007-10-30 05:20:38 +08:00
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bool "ACPI (Advanced Configuration and Power Interface) Support"
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2018-07-24 17:48:45 +08:00
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depends on ARCH_SUPPORTS_ACPI
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2007-02-16 11:34:36 +08:00
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select PNP
|
2018-12-31 04:40:05 +08:00
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select NLS
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2018-07-24 17:48:45 +08:00
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default y if X86
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2009-02-20 05:45:47 +08:00
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help
|
2005-04-17 06:20:36 +08:00
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Advanced Configuration and Power Interface (ACPI) support for
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2009-02-20 05:45:47 +08:00
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Linux requires an ACPI-compliant platform (hardware/firmware),
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2005-04-17 06:20:36 +08:00
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and assumes the presence of OS-directed configuration and power
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management (OSPM) software. This option will enlarge your
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kernel by about 70K.
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Linux ACPI provides a robust functional replacement for several
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legacy configuration and power management interfaces, including
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the Plug-and-Play BIOS specification (PnP BIOS), the
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MultiProcessor Specification (MPS), and the Advanced Power
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Management (APM) specification. If both ACPI and APM support
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2009-02-20 05:45:47 +08:00
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are configured, ACPI is used.
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2005-04-17 06:20:36 +08:00
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2009-02-20 05:45:47 +08:00
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The project home page for the Linux ACPI subsystem is here:
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2013-10-11 05:25:58 +08:00
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<https://01.org/linux-acpi>
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2005-04-17 06:20:36 +08:00
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Linux support for ACPI is based on Intel Corporation's ACPI
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2009-02-20 05:45:47 +08:00
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Component Architecture (ACPI CA). For more information on the
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ACPI CA, see:
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2020-07-18 02:24:36 +08:00
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<https://acpica.org/>
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2005-04-17 06:20:36 +08:00
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2014-04-08 20:59:48 +08:00
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ACPI is an open industry specification originally co-developed by
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Hewlett-Packard, Intel, Microsoft, Phoenix, and Toshiba. Currently,
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it is developed by the ACPI Specification Working Group (ASWG) under
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the UEFI Forum and any UEFI member can join the ASWG and contribute
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to the ACPI specification.
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2009-02-20 05:45:47 +08:00
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The specification is available at:
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2020-07-27 17:29:38 +08:00
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<https://uefi.org/specifications>
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2005-04-17 06:20:36 +08:00
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2005-05-27 16:53:27 +08:00
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if ACPI
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2014-07-18 18:02:52 +08:00
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config ACPI_LEGACY_TABLES_LOOKUP
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bool
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2014-07-18 18:02:54 +08:00
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config ARCH_MIGHT_HAVE_ACPI_PDC
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bool
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2015-03-25 01:58:51 +08:00
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config ACPI_GENERIC_GSI
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bool
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2015-03-24 22:02:39 +08:00
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config ACPI_SYSTEM_POWER_STATES_SUPPORT
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bool
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2015-06-11 00:08:52 +08:00
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config ACPI_CCA_REQUIRED
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bool
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2015-10-19 10:25:56 +08:00
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config ACPI_DEBUGGER
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2015-12-03 10:43:00 +08:00
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bool "AML debugger interface"
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2015-10-19 10:25:56 +08:00
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select ACPI_DEBUG
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help
|
2015-12-03 10:43:14 +08:00
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Enable in-kernel debugging of AML facilities: statistics,
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internal object dump, single step control method execution.
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2015-10-19 10:25:56 +08:00
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This is still under development, currently enabling this only
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results in the compilation of the ACPICA debugger files.
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2015-12-03 10:43:14 +08:00
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if ACPI_DEBUGGER
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config ACPI_DEBUGGER_USER
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tristate "Userspace debugger accessiblity"
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depends on DEBUG_FS
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help
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Export /sys/kernel/debug/acpi/acpidbg for userspace utilities
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to access the debugger functionalities.
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endif
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2016-09-28 04:54:13 +08:00
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config ACPI_SPCR_TABLE
|
2018-01-18 23:09:51 +08:00
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bool "ACPI Serial Port Console Redirection Support"
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default y if X86
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help
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Enable support for Serial Port Console Redirection (SPCR) Table.
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This table provides information about the configuration of the
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earlycon console.
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2016-09-28 04:54:13 +08:00
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2017-10-06 07:24:03 +08:00
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config ACPI_LPIT
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bool
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depends on X86_64
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default y
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2007-07-28 15:33:16 +08:00
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config ACPI_SLEEP
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bool
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2008-10-23 02:58:43 +08:00
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depends on SUSPEND || HIBERNATION
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2015-03-24 22:02:39 +08:00
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depends on ACPI_SYSTEM_POWER_STATES_SUPPORT
|
2007-07-28 15:33:16 +08:00
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default y
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2015-07-03 07:06:00 +08:00
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config ACPI_REV_OVERRIDE_POSSIBLE
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2016-09-17 22:44:17 +08:00
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bool "Allow supported ACPI revision to be overridden"
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2015-07-03 07:06:00 +08:00
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depends on X86
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default y
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help
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The platform firmware on some systems expects Linux to return "5" as
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the supported ACPI revision which makes it expose system configuration
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information in a special way.
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For example, based on what ACPI exports as the supported revision,
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Dell XPS 13 (2015) configures its audio device to either work in HDA
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mode or in I2S mode, where the former is supposed to be used on Linux
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until the latter is fully supported (in the kernel as well as in user
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space).
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This option enables a DMI-based quirk for the above Dell machine (so
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that HDA audio is exposed by the platform firmware to the kernel) and
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makes it possible to force the kernel to return "5" as the supported
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ACPI revision via the "acpi_rev_override" command line switch.
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2010-07-16 19:11:31 +08:00
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config ACPI_EC_DEBUGFS
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tristate "EC read/write access through /sys/kernel/debug/ec"
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help
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Say N to disable Embedded Controller /sys/kernel/debug interface
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2010-07-30 04:30:24 +08:00
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|
Be aware that using this interface can confuse your Embedded
|
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Controller in a way that a normal reboot is not enough. You then
|
2010-08-18 21:22:10 +08:00
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|
have to power off your system, and remove the laptop battery for
|
2010-07-30 04:30:24 +08:00
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some seconds.
|
2010-07-16 19:11:31 +08:00
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|
An Embedded Controller typically is available on laptops and reads
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|
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sensor values like battery state and temperature.
|
2010-07-30 04:30:24 +08:00
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The kernel accesses the EC through ACPI parsed code provided by BIOS
|
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|
tables. This option allows to access the EC directly without ACPI
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code being involved.
|
2010-07-16 19:11:31 +08:00
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Thus this option is a debug option that helps to write ACPI drivers
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and can be used to identify ACPI code or EC firmware bugs.
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|
2005-04-17 06:20:36 +08:00
|
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config ACPI_AC
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tristate "AC Adapter"
|
2010-10-08 13:54:57 +08:00
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select POWER_SUPPLY
|
2005-08-26 00:22:04 +08:00
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default y
|
2005-04-17 06:20:36 +08:00
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help
|
2009-02-20 05:45:47 +08:00
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This driver supports the AC Adapter object, which indicates
|
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whether a system is on AC or not. If you have a system that can
|
2005-08-26 00:22:04 +08:00
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switch between A/C and battery, say Y.
|
2005-04-17 06:20:36 +08:00
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|
2009-02-20 05:45:47 +08:00
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To compile this driver as a module, choose M here:
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the module will be called ac.
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|
2005-04-17 06:20:36 +08:00
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config ACPI_BATTERY
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tristate "Battery"
|
2010-10-08 13:54:57 +08:00
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select POWER_SUPPLY
|
2005-08-26 00:22:04 +08:00
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default y
|
2005-04-17 06:20:36 +08:00
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help
|
|
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|
This driver adds support for battery information through
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|
/proc/acpi/battery. If you have a mobile system with a battery,
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say Y.
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|
2009-02-20 05:45:47 +08:00
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To compile this driver as a module, choose M here:
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the module will be called battery.
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|
2005-04-17 06:20:36 +08:00
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config ACPI_BUTTON
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tristate "Button"
|
2006-11-09 13:40:13 +08:00
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depends on INPUT
|
2005-08-26 00:22:04 +08:00
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default y
|
2005-04-17 06:20:36 +08:00
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help
|
2009-02-20 05:45:47 +08:00
|
|
|
This driver handles events on the power, sleep, and lid buttons.
|
2013-10-13 06:11:00 +08:00
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A daemon reads events from input devices or via netlink and
|
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|
performs user-defined actions such as shutting down the system.
|
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|
This is necessary for software-controlled poweroff.
|
2009-02-20 05:45:47 +08:00
|
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To compile this driver as a module, choose M here:
|
|
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the module will be called button.
|
2005-04-17 06:20:36 +08:00
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|
2020-02-12 07:38:06 +08:00
|
|
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config ACPI_TINY_POWER_BUTTON
|
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|
|
tristate "Tiny Power Button Driver"
|
|
|
|
depends on !ACPI_BUTTON
|
|
|
|
help
|
|
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|
This driver provides a tiny alternative to the ACPI Button driver.
|
|
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|
The tiny power button driver only handles the power button. Rather
|
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|
than notifying userspace via the input layer or a netlink event, this
|
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|
driver directly signals the init process to shut down.
|
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|
This driver is particularly suitable for cloud and VM environments,
|
|
|
|
which use a simulated power button to initiate a controlled poweroff,
|
|
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but which may not want to run a separate userspace daemon to process
|
|
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|
input events.
|
|
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|
|
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|
|
config ACPI_TINY_POWER_BUTTON_SIGNAL
|
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|
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int "Tiny Power Button Signal"
|
|
|
|
depends on ACPI_TINY_POWER_BUTTON
|
|
|
|
default 38
|
|
|
|
help
|
|
|
|
Default signal to send to init in response to the power button.
|
|
|
|
|
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|
|
Likely values here include 38 (SIGRTMIN+4) to power off, or 2
|
|
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|
(SIGINT) to simulate Ctrl+Alt+Del.
|
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|
2005-04-17 06:20:36 +08:00
|
|
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config ACPI_VIDEO
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|
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|
tristate "Video"
|
2014-03-17 22:46:44 +08:00
|
|
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depends on X86 && BACKLIGHT_CLASS_DEVICE
|
2007-09-18 05:41:05 +08:00
|
|
|
depends on INPUT
|
2008-04-21 16:07:13 +08:00
|
|
|
select THERMAL
|
2005-04-17 06:20:36 +08:00
|
|
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help
|
2009-02-20 05:45:47 +08:00
|
|
|
This driver implements the ACPI Extensions For Display Adapters
|
2005-04-17 06:20:36 +08:00
|
|
|
for integrated graphics devices on motherboard, as specified in
|
2009-02-20 05:45:47 +08:00
|
|
|
ACPI 2.0 Specification, Appendix B. This supports basic operations
|
|
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|
such as defining the video POST device, retrieving EDID information,
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and setting up a video output.
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To compile this driver as a module, choose M here:
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the module will be called video.
|
2005-04-17 06:20:36 +08:00
|
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|
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config ACPI_FAN
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|
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|
tristate "Fan"
|
2014-06-19 15:43:29 +08:00
|
|
|
depends on THERMAL
|
2005-08-26 00:22:04 +08:00
|
|
|
default y
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
2009-02-20 05:45:47 +08:00
|
|
|
This driver supports ACPI fan devices, allowing user-mode
|
2005-04-17 06:20:36 +08:00
|
|
|
applications to perform basic fan control (on, off, status).
|
|
|
|
|
2009-02-20 05:45:47 +08:00
|
|
|
To compile this driver as a module, choose M here:
|
|
|
|
the module will be called fan.
|
|
|
|
|
2018-03-16 20:51:01 +08:00
|
|
|
config ACPI_TAD
|
|
|
|
tristate "ACPI Time and Alarm (TAD) Device Support"
|
|
|
|
depends on SYSFS && PM_SLEEP
|
|
|
|
help
|
|
|
|
The ACPI Time and Alarm (TAD) device is an alternative to the Real
|
|
|
|
Time Clock (RTC). Its wake timers allow the system to transition from
|
|
|
|
the S3 (or optionally S4/S5) state to S0 state after a time period
|
|
|
|
elapses. In comparison with the RTC Alarm, the TAD provides a larger
|
|
|
|
scale of flexibility in the wake timers. The time capabilities of the
|
|
|
|
TAD maintain the time of day information across platform power
|
|
|
|
transitions, and keep track of time even when the platform is turned
|
|
|
|
off.
|
|
|
|
|
2006-07-10 05:22:28 +08:00
|
|
|
config ACPI_DOCK
|
2008-09-27 11:10:28 +08:00
|
|
|
bool "Dock"
|
2006-07-10 05:22:28 +08:00
|
|
|
help
|
2009-02-20 05:45:47 +08:00
|
|
|
This driver supports ACPI-controlled docking stations and removable
|
|
|
|
drive bays such as the IBM Ultrabay and the Dell Module Bay.
|
2006-10-21 05:30:25 +08:00
|
|
|
|
2015-08-05 21:40:25 +08:00
|
|
|
config ACPI_CPU_FREQ_PSS
|
|
|
|
bool
|
|
|
|
select THERMAL
|
|
|
|
|
2016-07-20 01:52:53 +08:00
|
|
|
config ACPI_PROCESSOR_CSTATE
|
|
|
|
def_bool y
|
2019-12-16 19:07:01 +08:00
|
|
|
depends on ACPI_PROCESSOR
|
2016-07-20 01:52:53 +08:00
|
|
|
depends on IA64 || X86
|
|
|
|
|
2015-08-05 21:40:26 +08:00
|
|
|
config ACPI_PROCESSOR_IDLE
|
|
|
|
bool
|
|
|
|
select CPU_IDLE
|
|
|
|
|
2016-06-11 03:55:13 +08:00
|
|
|
config ACPI_MCFG
|
|
|
|
bool
|
|
|
|
|
2015-10-02 22:01:19 +08:00
|
|
|
config ACPI_CPPC_LIB
|
|
|
|
bool
|
|
|
|
depends on ACPI_PROCESSOR
|
|
|
|
select MAILBOX
|
|
|
|
select PCC
|
|
|
|
help
|
|
|
|
If this option is enabled, this file implements common functionality
|
|
|
|
to parse CPPC tables as described in the ACPI 5.1+ spec. The
|
|
|
|
routines implemented are meant to be used by other
|
|
|
|
drivers to control CPU performance using CPPC semantics.
|
|
|
|
If your platform does not support CPPC in firmware,
|
|
|
|
leave this option disabled.
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config ACPI_PROCESSOR
|
|
|
|
tristate "Processor"
|
2015-09-10 04:27:08 +08:00
|
|
|
depends on X86 || IA64 || ARM64
|
2016-07-20 01:52:59 +08:00
|
|
|
select ACPI_PROCESSOR_IDLE
|
2015-09-10 04:27:08 +08:00
|
|
|
select ACPI_CPU_FREQ_PSS if X86 || IA64
|
2005-08-26 00:22:04 +08:00
|
|
|
default y
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
2015-08-05 21:40:25 +08:00
|
|
|
This driver adds support for the ACPI Processor package. It is required
|
|
|
|
by several flavors of cpufreq performance-state, thermal, throttling and
|
|
|
|
idle drivers.
|
2009-02-20 05:45:47 +08:00
|
|
|
|
|
|
|
To compile this driver as a module, choose M here:
|
|
|
|
the module will be called processor.
|
2013-09-13 13:14:51 +08:00
|
|
|
|
2010-12-08 10:10:18 +08:00
|
|
|
config ACPI_IPMI
|
|
|
|
tristate "IPMI"
|
2017-03-25 22:02:54 +08:00
|
|
|
depends on IPMI_HANDLER
|
2010-12-08 10:10:18 +08:00
|
|
|
help
|
|
|
|
This driver enables the ACPI to access the BMC controller. And it
|
|
|
|
uses the IPMI request/response message to communicate with BMC
|
|
|
|
controller, which can be found on on the server.
|
|
|
|
|
|
|
|
To compile this driver as a module, choose M here:
|
|
|
|
the module will be called as acpi_ipmi.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
config ACPI_HOTPLUG_CPU
|
2005-07-30 16:18:00 +08:00
|
|
|
bool
|
2013-01-17 10:53:28 +08:00
|
|
|
depends on ACPI_PROCESSOR && HOTPLUG_CPU
|
2005-04-17 06:20:36 +08:00
|
|
|
select ACPI_CONTAINER
|
2005-07-30 16:18:00 +08:00
|
|
|
default y
|
2005-04-17 06:20:36 +08:00
|
|
|
|
ACPI: create Processor Aggregator Device driver
ACPI 4.0 created the logical "processor aggregator device" as
a mechinism for platforms to ask the OS to force otherwise busy
processors to enter (power saving) idle.
The intent is to lower power consumption to ride-out
transient electrical and thermal emergencies,
rather than powering off the server.
On platforms that can save more power/performance via P-states,
the platform will first exhaust P-states before forcing idle.
However, the relative benefit of P-states vs. idle states
is platform dependent, and thus this driver need not know
or care about it.
This driver does not use the kernel's CPU hot-plug mechanism
because after the transient emergency is over, the system must
be returned to its normal state, and hotplug would permanently
break both cpusets and binding.
So to force idle, the driver creates a power saving thread.
The scheduler will migrate the thread to the preferred CPU.
The thread has max priority and has SCHED_RR policy,
so it can occupy one CPU. To save power, the thread will
invoke the deep C-state entry instructions.
To avoid starvation, the thread will sleep 5% of the time
time for every second (current RT scheduler has threshold
to avoid starvation, but if other CPUs are idle,
the CPU can borrow CPU timer from other,
which makes the mechanism not work here)
Vaidyanathan Srinivasan has proposed scheduler enhancements
to allow injecting idle time into the system. This driver doesn't
depend on those enhancements, but could cut over to them
when they are available.
Peter Z. does not favor upstreaming this driver until
the those scheduler enhancements are in place. However,
we favor upstreaming this driver now because it is useful
now, and can be enhanced over time.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
NACKed-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-07-28 06:11:02 +08:00
|
|
|
config ACPI_PROCESSOR_AGGREGATOR
|
|
|
|
tristate "Processor Aggregator"
|
|
|
|
depends on ACPI_PROCESSOR
|
2009-09-27 14:35:55 +08:00
|
|
|
depends on X86
|
ACPI: create Processor Aggregator Device driver
ACPI 4.0 created the logical "processor aggregator device" as
a mechinism for platforms to ask the OS to force otherwise busy
processors to enter (power saving) idle.
The intent is to lower power consumption to ride-out
transient electrical and thermal emergencies,
rather than powering off the server.
On platforms that can save more power/performance via P-states,
the platform will first exhaust P-states before forcing idle.
However, the relative benefit of P-states vs. idle states
is platform dependent, and thus this driver need not know
or care about it.
This driver does not use the kernel's CPU hot-plug mechanism
because after the transient emergency is over, the system must
be returned to its normal state, and hotplug would permanently
break both cpusets and binding.
So to force idle, the driver creates a power saving thread.
The scheduler will migrate the thread to the preferred CPU.
The thread has max priority and has SCHED_RR policy,
so it can occupy one CPU. To save power, the thread will
invoke the deep C-state entry instructions.
To avoid starvation, the thread will sleep 5% of the time
time for every second (current RT scheduler has threshold
to avoid starvation, but if other CPUs are idle,
the CPU can borrow CPU timer from other,
which makes the mechanism not work here)
Vaidyanathan Srinivasan has proposed scheduler enhancements
to allow injecting idle time into the system. This driver doesn't
depend on those enhancements, but could cut over to them
when they are available.
Peter Z. does not favor upstreaming this driver until
the those scheduler enhancements are in place. However,
we favor upstreaming this driver now because it is useful
now, and can be enhanced over time.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
NACKed-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-07-28 06:11:02 +08:00
|
|
|
help
|
|
|
|
ACPI 4.0 defines processor Aggregator, which enables OS to perform
|
2009-10-09 21:53:24 +08:00
|
|
|
specific processor configuration and control that applies to all
|
ACPI: create Processor Aggregator Device driver
ACPI 4.0 created the logical "processor aggregator device" as
a mechinism for platforms to ask the OS to force otherwise busy
processors to enter (power saving) idle.
The intent is to lower power consumption to ride-out
transient electrical and thermal emergencies,
rather than powering off the server.
On platforms that can save more power/performance via P-states,
the platform will first exhaust P-states before forcing idle.
However, the relative benefit of P-states vs. idle states
is platform dependent, and thus this driver need not know
or care about it.
This driver does not use the kernel's CPU hot-plug mechanism
because after the transient emergency is over, the system must
be returned to its normal state, and hotplug would permanently
break both cpusets and binding.
So to force idle, the driver creates a power saving thread.
The scheduler will migrate the thread to the preferred CPU.
The thread has max priority and has SCHED_RR policy,
so it can occupy one CPU. To save power, the thread will
invoke the deep C-state entry instructions.
To avoid starvation, the thread will sleep 5% of the time
time for every second (current RT scheduler has threshold
to avoid starvation, but if other CPUs are idle,
the CPU can borrow CPU timer from other,
which makes the mechanism not work here)
Vaidyanathan Srinivasan has proposed scheduler enhancements
to allow injecting idle time into the system. This driver doesn't
depend on those enhancements, but could cut over to them
when they are available.
Peter Z. does not favor upstreaming this driver until
the those scheduler enhancements are in place. However,
we favor upstreaming this driver now because it is useful
now, and can be enhanced over time.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
NACKed-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-07-28 06:11:02 +08:00
|
|
|
processors in the platform. Currently only logical processor idling
|
|
|
|
is defined, which is to reduce power consumption. This driver
|
2009-10-09 21:53:24 +08:00
|
|
|
supports the new device.
|
ACPI: create Processor Aggregator Device driver
ACPI 4.0 created the logical "processor aggregator device" as
a mechinism for platforms to ask the OS to force otherwise busy
processors to enter (power saving) idle.
The intent is to lower power consumption to ride-out
transient electrical and thermal emergencies,
rather than powering off the server.
On platforms that can save more power/performance via P-states,
the platform will first exhaust P-states before forcing idle.
However, the relative benefit of P-states vs. idle states
is platform dependent, and thus this driver need not know
or care about it.
This driver does not use the kernel's CPU hot-plug mechanism
because after the transient emergency is over, the system must
be returned to its normal state, and hotplug would permanently
break both cpusets and binding.
So to force idle, the driver creates a power saving thread.
The scheduler will migrate the thread to the preferred CPU.
The thread has max priority and has SCHED_RR policy,
so it can occupy one CPU. To save power, the thread will
invoke the deep C-state entry instructions.
To avoid starvation, the thread will sleep 5% of the time
time for every second (current RT scheduler has threshold
to avoid starvation, but if other CPUs are idle,
the CPU can borrow CPU timer from other,
which makes the mechanism not work here)
Vaidyanathan Srinivasan has proposed scheduler enhancements
to allow injecting idle time into the system. This driver doesn't
depend on those enhancements, but could cut over to them
when they are available.
Peter Z. does not favor upstreaming this driver until
the those scheduler enhancements are in place. However,
we favor upstreaming this driver now because it is useful
now, and can be enhanced over time.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
NACKed-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-07-28 06:11:02 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config ACPI_THERMAL
|
|
|
|
tristate "Thermal Zone"
|
|
|
|
depends on ACPI_PROCESSOR
|
2008-01-17 15:51:11 +08:00
|
|
|
select THERMAL
|
2005-08-26 00:22:04 +08:00
|
|
|
default y
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
2009-02-20 05:45:47 +08:00
|
|
|
This driver supports ACPI thermal zones. Most mobile and
|
2005-04-17 06:20:36 +08:00
|
|
|
some desktop systems support ACPI thermal zones. It is HIGHLY
|
|
|
|
recommended that this option be enabled, as your processor(s)
|
|
|
|
may be damaged without it.
|
|
|
|
|
2009-02-20 05:45:47 +08:00
|
|
|
To compile this driver as a module, choose M here:
|
|
|
|
the module will be called thermal.
|
|
|
|
|
2008-02-23 03:25:04 +08:00
|
|
|
config ACPI_CUSTOM_DSDT_FILE
|
|
|
|
string "Custom DSDT Table file to include"
|
|
|
|
default ""
|
2005-04-17 06:20:36 +08:00
|
|
|
depends on !STANDALONE
|
|
|
|
help
|
2008-02-07 08:28:02 +08:00
|
|
|
This option supports a custom DSDT by linking it into the kernel.
|
2019-06-08 02:54:32 +08:00
|
|
|
See Documentation/admin-guide/acpi/dsdt-override.rst
|
2008-02-07 08:28:02 +08:00
|
|
|
|
2006-03-25 01:23:14 +08:00
|
|
|
Enter the full path name to the file which includes the AmlCode
|
2018-11-13 18:46:23 +08:00
|
|
|
or dsdt_aml_code declaration.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2008-02-23 03:25:04 +08:00
|
|
|
If unsure, don't enter a file name.
|
|
|
|
|
|
|
|
config ACPI_CUSTOM_DSDT
|
|
|
|
bool
|
|
|
|
default ACPI_CUSTOM_DSDT_FILE != ""
|
|
|
|
|
2016-06-20 18:56:12 +08:00
|
|
|
config ARCH_HAS_ACPI_TABLE_UPGRADE
|
|
|
|
def_bool n
|
|
|
|
|
2016-04-11 10:13:33 +08:00
|
|
|
config ACPI_TABLE_UPGRADE
|
|
|
|
bool "Allow upgrading ACPI tables via initrd"
|
2016-06-20 18:56:12 +08:00
|
|
|
depends on BLK_DEV_INITRD && ARCH_HAS_ACPI_TABLE_UPGRADE
|
2016-04-11 10:13:33 +08:00
|
|
|
default y
|
2012-10-01 06:23:54 +08:00
|
|
|
help
|
2016-04-11 10:13:33 +08:00
|
|
|
This option provides functionality to upgrade arbitrary ACPI tables
|
2012-10-01 06:23:54 +08:00
|
|
|
via initrd. No functional change if no ACPI tables are passed via
|
|
|
|
initrd, therefore it's safe to say Y.
|
2019-06-08 02:54:32 +08:00
|
|
|
See Documentation/admin-guide/acpi/initrd_table_override.rst for details
|
2012-10-01 06:23:54 +08:00
|
|
|
|
2018-12-18 14:02:45 +08:00
|
|
|
config ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD
|
|
|
|
bool "Override ACPI tables from built-in initrd"
|
|
|
|
depends on ACPI_TABLE_UPGRADE
|
2021-07-15 17:26:01 +08:00
|
|
|
depends on INITRAMFS_SOURCE!="" && INITRAMFS_COMPRESSION_NONE
|
2018-12-18 14:02:45 +08:00
|
|
|
help
|
|
|
|
This option provides functionality to override arbitrary ACPI tables
|
|
|
|
from built-in uncompressed initrd.
|
|
|
|
|
2019-06-08 02:54:32 +08:00
|
|
|
See Documentation/admin-guide/acpi/initrd_table_override.rst for details
|
2018-12-18 14:02:45 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config ACPI_DEBUG
|
|
|
|
bool "Debug Statements"
|
|
|
|
help
|
2008-11-08 07:58:05 +08:00
|
|
|
The ACPI subsystem can produce debug output. Saying Y enables this
|
|
|
|
output and increases the kernel size by around 50K.
|
|
|
|
|
|
|
|
Use the acpi.debug_layer and acpi.debug_level kernel command-line
|
2019-06-08 02:54:32 +08:00
|
|
|
parameters documented in Documentation/firmware-guide/acpi/debug.rst and
|
2016-10-18 20:12:27 +08:00
|
|
|
Documentation/admin-guide/kernel-parameters.rst to control the type and
|
2008-11-08 07:58:05 +08:00
|
|
|
amount of debug output.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2008-06-11 05:30:42 +08:00
|
|
|
config ACPI_PCI_SLOT
|
2013-01-19 00:07:42 +08:00
|
|
|
bool "PCI slot detection driver"
|
2018-12-20 06:46:59 +08:00
|
|
|
depends on SYSFS && PCI
|
2008-06-11 05:30:42 +08:00
|
|
|
help
|
2009-02-20 05:45:47 +08:00
|
|
|
This driver creates entries in /sys/bus/pci/slots/ for all PCI
|
|
|
|
slots in the system. This can help correlate PCI bus addresses,
|
|
|
|
i.e., segment/bus/device/function tuples, with physical slots in
|
|
|
|
the system. If you are unsure, say N.
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config ACPI_CONTAINER
|
2013-02-22 04:05:51 +08:00
|
|
|
bool "Container and Module Devices"
|
2013-03-11 18:53:48 +08:00
|
|
|
default (ACPI_HOTPLUG_MEMORY || ACPI_HOTPLUG_CPU)
|
2009-02-20 05:45:47 +08:00
|
|
|
help
|
|
|
|
This driver supports ACPI Container and Module devices (IDs
|
|
|
|
ACPI0004, PNP0A05, and PNP0A06).
|
2005-03-02 13:00:00 +08:00
|
|
|
|
2009-02-20 05:45:47 +08:00
|
|
|
This helps support hotplug of nodes, CPUs, and memory.
|
|
|
|
|
|
|
|
To compile this driver as a module, choose M here:
|
|
|
|
the module will be called container.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
config ACPI_HOTPLUG_MEMORY
|
2013-03-04 06:18:03 +08:00
|
|
|
bool "Memory Hotplug"
|
2006-06-27 17:53:30 +08:00
|
|
|
depends on MEMORY_HOTPLUG
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
2009-02-20 05:45:47 +08:00
|
|
|
This driver supports ACPI memory hotplug. The driver
|
|
|
|
fields notifications on ACPI memory devices (PNP0C80),
|
|
|
|
which represent memory ranges that may be onlined or
|
|
|
|
offlined during runtime.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2009-02-20 05:45:47 +08:00
|
|
|
If your hardware and firmware do not support adding or
|
|
|
|
removing memory devices at runtime, you need not enable
|
|
|
|
this driver.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2009-02-20 05:45:47 +08:00
|
|
|
To compile this driver as a module, choose M here:
|
|
|
|
the module will be called acpi_memhotplug.
|
2006-07-01 23:36:54 +08:00
|
|
|
|
2015-02-05 13:44:49 +08:00
|
|
|
config ACPI_HOTPLUG_IOAPIC
|
|
|
|
bool
|
|
|
|
depends on PCI
|
|
|
|
depends on X86_IO_APIC
|
|
|
|
default y
|
|
|
|
|
2006-07-01 23:36:54 +08:00
|
|
|
config ACPI_SBS
|
2007-09-26 23:43:48 +08:00
|
|
|
tristate "Smart Battery System"
|
2007-03-19 22:45:50 +08:00
|
|
|
depends on X86
|
2010-10-08 13:54:57 +08:00
|
|
|
select POWER_SUPPLY
|
2006-07-01 23:36:54 +08:00
|
|
|
help
|
2009-02-20 05:45:47 +08:00
|
|
|
This driver supports the Smart Battery System, another
|
2007-09-26 23:43:48 +08:00
|
|
|
type of access to battery information, found on some laptops.
|
2006-07-01 23:36:54 +08:00
|
|
|
|
2009-02-20 05:45:47 +08:00
|
|
|
To compile this driver as a module, choose M here:
|
|
|
|
the modules will be called sbs and sbshc.
|
|
|
|
|
2010-05-18 14:35:17 +08:00
|
|
|
config ACPI_HED
|
|
|
|
tristate "Hardware Error Device"
|
|
|
|
help
|
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This driver supports the Hardware Error Device (PNP0C33),
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which is used to report some hardware errors notified via
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SCI, mainly the corrected errors.
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2011-05-26 18:26:24 +08:00
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config ACPI_CUSTOM_METHOD
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tristate "Allow ACPI methods to be inserted/replaced at run time"
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depends on DEBUG_FS
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help
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2012-01-04 00:49:48 +08:00
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This debug facility allows ACPI AML methods to be inserted and/or
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2011-05-26 18:26:24 +08:00
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replaced without rebooting the system. For details refer to:
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2019-06-08 02:54:32 +08:00
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Documentation/firmware-guide/acpi/method-customizing.rst.
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2011-05-26 18:26:24 +08:00
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NOTE: This option is security sensitive, because it allows arbitrary
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kernel memory to be written to by root (uid=0) users, allowing them
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to bypass certain security measures (e.g. if root is not allowed to
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load additional kernel modules after boot, this feature may be used
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to override that restriction).
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2012-02-01 02:19:20 +08:00
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config ACPI_BGRT
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2012-09-29 08:57:05 +08:00
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bool "Boottime Graphics Resource Table support"
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2017-04-05 00:02:41 +08:00
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depends on EFI && (X86 || ARM64)
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2019-11-20 21:43:10 +08:00
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help
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2012-02-01 02:19:20 +08:00
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This driver adds support for exposing the ACPI Boottime Graphics
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Resource Table, which allows the operating system to obtain
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data from the firmware boot splash. It will appear under
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/sys/firmware/acpi/bgrt/ .
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2014-01-18 02:51:30 +08:00
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config ACPI_REDUCED_HARDWARE_ONLY
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bool "Hardware-reduced ACPI support only" if EXPERT
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def_bool n
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help
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2014-11-14 17:44:07 +08:00
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This config item changes the way the ACPI code is built. When this
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option is selected, the kernel will use a specialized version of
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ACPICA that ONLY supports the ACPI "reduced hardware" mode. The
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resulting kernel will be smaller but it will also be restricted to
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running in ACPI reduced hardware mode ONLY.
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2014-01-18 02:51:30 +08:00
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2014-11-14 17:44:07 +08:00
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If you are unsure what to do, do not enable this option.
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2014-01-18 02:51:30 +08:00
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2016-07-24 12:24:19 +08:00
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source "drivers/acpi/nfit/Kconfig"
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2019-11-07 09:42:55 +08:00
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source "drivers/acpi/numa/Kconfig"
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2010-05-18 14:35:12 +08:00
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source "drivers/acpi/apei/Kconfig"
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2016-07-18 04:45:32 +08:00
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source "drivers/acpi/dptf/Kconfig"
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2010-05-18 14:35:12 +08:00
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2016-09-20 20:30:51 +08:00
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config ACPI_WATCHDOG
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bool
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2013-10-22 05:29:25 +08:00
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config ACPI_EXTLOG
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tristate "Extended Error Log support"
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2017-02-03 21:17:43 +08:00
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depends on X86_MCE && X86_LOCAL_APIC && EDAC
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2013-10-29 05:06:55 +08:00
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select UEFI_CPER
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2013-10-22 05:29:25 +08:00
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help
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Certain usages such as Predictive Failure Analysis (PFA) require
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more information about the error than what can be described in
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processor machine check banks. Most server processors log
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additional information about the error in processor uncore
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registers. Since the addresses and layout of these registers vary
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widely from one processor to another, system software cannot
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readily make use of them. To complicate matters further, some of
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the additional error information cannot be constructed without
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detailed knowledge about platform topology.
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Enhanced MCA Logging allows firmware to provide additional error
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information to system software, synchronous with MCE or CMCI. This
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2014-06-18 10:33:07 +08:00
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driver adds support for that functionality with corresponding
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tracepoint which carries that information to userspace.
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2013-10-22 05:29:25 +08:00
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2018-10-16 07:11:31 +08:00
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config ACPI_ADXL
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bool
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2016-07-09 00:13:13 +08:00
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config ACPI_CONFIGFS
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tristate "ACPI configfs support"
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select CONFIGFS_FS
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help
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Select this option to enable support for ACPI configuration from
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userspace. The configurable ACPI groups will be visible under
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/config/acpi, assuming configfs is mounted under /config.
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2016-09-13 02:54:20 +08:00
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if ARM64
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source "drivers/acpi/arm64/Kconfig"
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2018-05-12 07:58:01 +08:00
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config ACPI_PPTT
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bool
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2016-09-13 02:54:20 +08:00
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endif
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2020-08-14 21:27:25 +08:00
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source "drivers/acpi/pmic/Kconfig"
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2005-04-17 06:20:36 +08:00
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endif # ACPI
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2017-11-27 16:11:48 +08:00
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config X86_PM_TIMER
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bool "Power Management Timer Support" if EXPERT
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depends on X86 && (ACPI || JAILHOUSE_GUEST)
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default y
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help
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The Power Management Timer is available on all ACPI-capable,
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in most cases even if ACPI is unusable or blacklisted.
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This timing source is not affected by power management features
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like aggressive processor idling, throttling, frequency and/or
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voltage scaling, unlike the commonly used Time Stamp Counter
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(TSC) timing source.
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You should nearly always say Y here because many modern
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systems require this timer.
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