1 # SPDX-License-Identifier: GPL-2.0
6 config ARCH_SUPPORTS_ACPI
10 bool "ACPI (Advanced Configuration and Power Interface) Support"
11 depends on ARCH_SUPPORTS_ACPI
16 Advanced Configuration and Power Interface (ACPI) support for
17 Linux requires an ACPI-compliant platform (hardware/firmware),
18 and assumes the presence of OS-directed configuration and power
19 management (OSPM) software. This option will enlarge your
22 Linux ACPI provides a robust functional replacement for several
23 legacy configuration and power management interfaces, including
24 the Plug-and-Play BIOS specification (PnP BIOS), the
25 MultiProcessor Specification (MPS), and the Advanced Power
26 Management (APM) specification. If both ACPI and APM support
27 are configured, ACPI is used.
29 The project home page for the Linux ACPI subsystem is here:
30 <https://01.org/linux-acpi>
32 Linux support for ACPI is based on Intel Corporation's ACPI
33 Component Architecture (ACPI CA). For more information on the
37 ACPI is an open industry specification originally co-developed by
38 Hewlett-Packard, Intel, Microsoft, Phoenix, and Toshiba. Currently,
39 it is developed by the ACPI Specification Working Group (ASWG) under
40 the UEFI Forum and any UEFI member can join the ASWG and contribute
41 to the ACPI specification.
42 The specification is available at:
43 <https://uefi.org/specifications>
47 config ACPI_LEGACY_TABLES_LOOKUP
50 config ARCH_MIGHT_HAVE_ACPI_PDC
53 config ACPI_GENERIC_GSI
56 config ACPI_SYSTEM_POWER_STATES_SUPPORT
59 config ACPI_CCA_REQUIRED
66 bool "AML debugger interface"
69 Enable in-kernel debugging of AML facilities: statistics,
70 internal object dump, single step control method execution.
71 This is still under development, currently enabling this only
72 results in the compilation of the ACPICA debugger files.
76 config ACPI_DEBUGGER_USER
77 tristate "Userspace debugger accessibility"
80 Export /sys/kernel/debug/acpi/acpidbg for userspace utilities
81 to access the debugger functionalities.
85 config ACPI_SPCR_TABLE
86 bool "ACPI Serial Port Console Redirection Support"
89 Enable support for Serial Port Console Redirection (SPCR) Table.
90 This table provides information about the configuration of the
94 bool "ACPI Firmware Performance Data Table (FPDT) support"
97 Enable support for the Firmware Performance Data Table (FPDT).
98 This table provides information on the timing of the system
99 boot, S3 suspend and S3 resume firmware code paths.
108 depends on SUSPEND || HIBERNATION
109 depends on ACPI_SYSTEM_POWER_STATES_SUPPORT
112 config ACPI_REV_OVERRIDE_POSSIBLE
113 bool "Allow supported ACPI revision to be overridden"
117 The platform firmware on some systems expects Linux to return "5" as
118 the supported ACPI revision which makes it expose system configuration
119 information in a special way.
121 For example, based on what ACPI exports as the supported revision,
122 Dell XPS 13 (2015) configures its audio device to either work in HDA
123 mode or in I2S mode, where the former is supposed to be used on Linux
124 until the latter is fully supported (in the kernel as well as in user
127 This option enables a DMI-based quirk for the above Dell machine (so
128 that HDA audio is exposed by the platform firmware to the kernel) and
129 makes it possible to force the kernel to return "5" as the supported
130 ACPI revision via the "acpi_rev_override" command line switch.
132 config ACPI_EC_DEBUGFS
133 tristate "EC read/write access through /sys/kernel/debug/ec"
135 Say N to disable Embedded Controller /sys/kernel/debug interface
137 Be aware that using this interface can confuse your Embedded
138 Controller in a way that a normal reboot is not enough. You then
139 have to power off your system, and remove the laptop battery for
141 An Embedded Controller typically is available on laptops and reads
142 sensor values like battery state and temperature.
143 The kernel accesses the EC through ACPI parsed code provided by BIOS
144 tables. This option allows to access the EC directly without ACPI
146 Thus this option is a debug option that helps to write ACPI drivers
147 and can be used to identify ACPI code or EC firmware bugs.
150 tristate "AC Adapter"
154 This driver supports the AC Adapter object, which indicates
155 whether a system is on AC or not. If you have a system that can
156 switch between A/C and battery, say Y.
158 To compile this driver as a module, choose M here:
159 the module will be called ac.
166 This driver adds support for battery information through
167 /proc/acpi/battery. If you have a mobile system with a battery,
170 To compile this driver as a module, choose M here:
171 the module will be called battery.
178 This driver handles events on the power, sleep, and lid buttons.
179 A daemon reads events from input devices or via netlink and
180 performs user-defined actions such as shutting down the system.
181 This is necessary for software-controlled poweroff.
183 To compile this driver as a module, choose M here:
184 the module will be called button.
186 config ACPI_TINY_POWER_BUTTON
187 tristate "Tiny Power Button Driver"
188 depends on !ACPI_BUTTON
190 This driver provides a tiny alternative to the ACPI Button driver.
191 The tiny power button driver only handles the power button. Rather
192 than notifying userspace via the input layer or a netlink event, this
193 driver directly signals the init process to shut down.
195 This driver is particularly suitable for cloud and VM environments,
196 which use a simulated power button to initiate a controlled poweroff,
197 but which may not want to run a separate userspace daemon to process
200 config ACPI_TINY_POWER_BUTTON_SIGNAL
201 int "Tiny Power Button Signal"
202 depends on ACPI_TINY_POWER_BUTTON
205 Default signal to send to init in response to the power button.
207 Likely values here include 38 (SIGRTMIN+4) to power off, or 2
208 (SIGINT) to simulate Ctrl+Alt+Del.
212 depends on X86 && BACKLIGHT_CLASS_DEVICE
216 This driver implements the ACPI Extensions For Display Adapters
217 for integrated graphics devices on motherboard, as specified in
218 ACPI 2.0 Specification, Appendix B. This supports basic operations
219 such as defining the video POST device, retrieving EDID information,
220 and setting up a video output.
222 To compile this driver as a module, choose M here:
223 the module will be called video.
230 This driver supports ACPI fan devices, allowing user-mode
231 applications to perform basic fan control (on, off, status).
233 To compile this driver as a module, choose M here:
234 the module will be called fan.
237 tristate "ACPI Time and Alarm (TAD) Device Support"
238 depends on SYSFS && PM_SLEEP
240 The ACPI Time and Alarm (TAD) device is an alternative to the Real
241 Time Clock (RTC). Its wake timers allow the system to transition from
242 the S3 (or optionally S4/S5) state to S0 state after a time period
243 elapses. In comparison with the RTC Alarm, the TAD provides a larger
244 scale of flexibility in the wake timers. The time capabilities of the
245 TAD maintain the time of day information across platform power
246 transitions, and keep track of time even when the platform is turned
252 This driver supports ACPI-controlled docking stations and removable
253 drive bays such as the IBM Ultrabay and the Dell Module Bay.
255 config ACPI_CPU_FREQ_PSS
259 config ACPI_PROCESSOR_CSTATE
261 depends on ACPI_PROCESSOR
262 depends on IA64 || X86
264 config ACPI_PROCESSOR_IDLE
273 depends on ACPI_PROCESSOR
277 If this option is enabled, this file implements common functionality
278 to parse CPPC tables as described in the ACPI 5.1+ spec. The
279 routines implemented are meant to be used by other
280 drivers to control CPU performance using CPPC semantics.
281 If your platform does not support CPPC in firmware,
282 leave this option disabled.
284 config ACPI_PROCESSOR
286 depends on X86 || IA64 || ARM64 || LOONGARCH
287 select ACPI_PROCESSOR_IDLE
288 select ACPI_CPU_FREQ_PSS if X86 || IA64 || LOONGARCH
291 This driver adds support for the ACPI Processor package. It is required
292 by several flavors of cpufreq performance-state, thermal, throttling and
295 To compile this driver as a module, choose M here:
296 the module will be called processor.
300 depends on IPMI_HANDLER
302 This driver enables the ACPI to access the BMC controller. And it
303 uses the IPMI request/response message to communicate with BMC
304 controller, which can be found on on the server.
306 To compile this driver as a module, choose M here:
307 the module will be called as acpi_ipmi.
309 config ACPI_HOTPLUG_CPU
311 depends on ACPI_PROCESSOR && HOTPLUG_CPU
312 select ACPI_CONTAINER
315 config ACPI_PROCESSOR_AGGREGATOR
316 tristate "Processor Aggregator"
317 depends on ACPI_PROCESSOR
320 ACPI 4.0 defines processor Aggregator, which enables OS to perform
321 specific processor configuration and control that applies to all
322 processors in the platform. Currently only logical processor idling
323 is defined, which is to reduce power consumption. This driver
324 supports the new device.
327 tristate "Thermal Zone"
328 depends on ACPI_PROCESSOR
332 This driver supports ACPI thermal zones. Most mobile and
333 some desktop systems support ACPI thermal zones. It is HIGHLY
334 recommended that this option be enabled, as your processor(s)
335 may be damaged without it.
337 To compile this driver as a module, choose M here:
338 the module will be called thermal.
340 config ACPI_PLATFORM_PROFILE
343 config ACPI_CUSTOM_DSDT_FILE
344 string "Custom DSDT Table file to include"
346 depends on !STANDALONE
348 This option supports a custom DSDT by linking it into the kernel.
349 See Documentation/admin-guide/acpi/dsdt-override.rst
351 Enter the full path name to the file which includes the AmlCode
352 or dsdt_aml_code declaration.
354 If unsure, don't enter a file name.
356 config ACPI_CUSTOM_DSDT
358 default ACPI_CUSTOM_DSDT_FILE != ""
360 config ARCH_HAS_ACPI_TABLE_UPGRADE
363 config ACPI_TABLE_UPGRADE
364 bool "Allow upgrading ACPI tables via initrd"
365 depends on BLK_DEV_INITRD && ARCH_HAS_ACPI_TABLE_UPGRADE
368 This option provides functionality to upgrade arbitrary ACPI tables
369 via initrd. No functional change if no ACPI tables are passed via
370 initrd, therefore it's safe to say Y.
371 See Documentation/admin-guide/acpi/initrd_table_override.rst for details
373 config ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD
374 bool "Override ACPI tables from built-in initrd"
375 depends on ACPI_TABLE_UPGRADE
376 depends on INITRAMFS_SOURCE!="" && INITRAMFS_COMPRESSION_NONE
378 This option provides functionality to override arbitrary ACPI tables
379 from built-in uncompressed initrd.
381 See Documentation/admin-guide/acpi/initrd_table_override.rst for details
384 bool "Debug Statements"
386 The ACPI subsystem can produce debug output. Saying Y enables this
387 output and increases the kernel size by around 50K.
389 Use the acpi.debug_layer and acpi.debug_level kernel command-line
390 parameters documented in Documentation/firmware-guide/acpi/debug.rst and
391 Documentation/admin-guide/kernel-parameters.rst to control the type and
392 amount of debug output.
395 bool "PCI slot detection driver"
396 depends on SYSFS && PCI
398 This driver creates entries in /sys/bus/pci/slots/ for all PCI
399 slots in the system. This can help correlate PCI bus addresses,
400 i.e., segment/bus/device/function tuples, with physical slots in
401 the system. If you are unsure, say N.
403 config ACPI_CONTAINER
404 bool "Container and Module Devices"
405 default (ACPI_HOTPLUG_MEMORY || ACPI_HOTPLUG_CPU)
407 This driver supports ACPI Container and Module devices (IDs
408 ACPI0004, PNP0A05, and PNP0A06).
410 This helps support hotplug of nodes, CPUs, and memory.
412 config ACPI_HOTPLUG_MEMORY
413 bool "Memory Hotplug"
414 depends on MEMORY_HOTPLUG
416 This driver supports ACPI memory hotplug. The driver
417 fields notifications on ACPI memory devices (PNP0C80),
418 which represent memory ranges that may be onlined or
419 offlined during runtime.
421 If your hardware and firmware do not support adding or
422 removing memory devices at runtime, you need not enable
425 config ACPI_HOTPLUG_IOAPIC
428 depends on X86_IO_APIC
432 tristate "Smart Battery System"
436 This driver supports the Smart Battery System, another
437 type of access to battery information, found on some laptops.
439 To compile this driver as a module, choose M here:
440 the modules will be called sbs and sbshc.
443 tristate "Hardware Error Device"
445 This driver supports the Hardware Error Device (PNP0C33),
446 which is used to report some hardware errors notified via
447 SCI, mainly the corrected errors.
449 config ACPI_CUSTOM_METHOD
450 tristate "Allow ACPI methods to be inserted/replaced at run time"
453 This debug facility allows ACPI AML methods to be inserted and/or
454 replaced without rebooting the system. For details refer to:
455 Documentation/firmware-guide/acpi/method-customizing.rst.
457 NOTE: This option is security sensitive, because it allows arbitrary
458 kernel memory to be written to by root (uid=0) users, allowing them
459 to bypass certain security measures (e.g. if root is not allowed to
460 load additional kernel modules after boot, this feature may be used
461 to override that restriction).
464 bool "Boottime Graphics Resource Table support"
465 depends on EFI && (X86 || ARM64)
467 This driver adds support for exposing the ACPI Boottime Graphics
468 Resource Table, which allows the operating system to obtain
469 data from the firmware boot splash. It will appear under
470 /sys/firmware/acpi/bgrt/ .
472 config ACPI_REDUCED_HARDWARE_ONLY
473 bool "Hardware-reduced ACPI support only" if EXPERT
476 This config item changes the way the ACPI code is built. When this
477 option is selected, the kernel will use a specialized version of
478 ACPICA that ONLY supports the ACPI "reduced hardware" mode. The
479 resulting kernel will be smaller but it will also be restricted to
480 running in ACPI reduced hardware mode ONLY.
482 If you are unsure what to do, do not enable this option.
484 source "drivers/acpi/nfit/Kconfig"
485 source "drivers/acpi/numa/Kconfig"
486 source "drivers/acpi/apei/Kconfig"
487 source "drivers/acpi/dptf/Kconfig"
493 tristate "Extended Error Log support"
494 depends on X86_MCE && X86_LOCAL_APIC && EDAC
497 Certain usages such as Predictive Failure Analysis (PFA) require
498 more information about the error than what can be described in
499 processor machine check banks. Most server processors log
500 additional information about the error in processor uncore
501 registers. Since the addresses and layout of these registers vary
502 widely from one processor to another, system software cannot
503 readily make use of them. To complicate matters further, some of
504 the additional error information cannot be constructed without
505 detailed knowledge about platform topology.
507 Enhanced MCA Logging allows firmware to provide additional error
508 information to system software, synchronous with MCE or CMCI. This
509 driver adds support for that functionality with corresponding
510 tracepoint which carries that information to userspace.
516 tristate "ACPI configfs support"
519 Select this option to enable support for ACPI configuration from
520 userspace. The configurable ACPI groups will be visible under
521 /config/acpi, assuming configfs is mounted under /config.
524 tristate "ACPI Platform Firmware Runtime Update and Telemetry"
527 This mechanism allows certain pieces of the platform firmware
528 to be updated on the fly while the system is running (runtime)
529 without the need to restart it, which is key in the cases when
530 the system needs to be available 100% of the time and it cannot
531 afford the downtime related to restarting it, or when the work
532 carried out by the system is particularly important, so it cannot
533 be interrupted, and it is not practical to wait until it is complete.
535 The existing firmware code can be modified (driver update) or
536 extended by adding new code to the firmware (code injection).
538 Besides, the telemetry driver allows user space to fetch telemetry
539 data from the firmware with the help of the Platform Firmware Runtime
542 To compile the drivers as modules, choose M here:
543 the modules will be called pfr_update and pfr_telemetry.
546 source "drivers/acpi/arm64/Kconfig"
553 bool "ACPI PCC Address Space"
557 The PCC Address Space also referred as PCC Operation Region pertains
558 to the region of PCC subspace that succeeds the PCC signature.
560 The PCC Operation Region works in conjunction with the PCC Table
561 (Platform Communications Channel Table). PCC subspaces that are
562 marked for use as PCC Operation Regions must not be used as PCC
563 subspaces for the standard ACPI features such as CPPC, RASF, PDTT and
564 MPST. These standard features must always use the PCC Table instead.
566 Enable this feature if you want to set up and install the PCC Address
567 Space handler to handle PCC OpRegion in the firmware.
569 source "drivers/acpi/pmic/Kconfig"
577 bool "Power Management Timer Support" if EXPERT
578 depends on X86 && (ACPI || JAILHOUSE_GUEST)
581 The Power Management Timer is available on all ACPI-capable,
582 in most cases even if ACPI is unusable or blacklisted.
584 This timing source is not affected by power management features
585 like aggressive processor idling, throttling, frequency and/or
586 voltage scaling, unlike the commonly used Time Stamp Counter
589 You should nearly always say Y here because many modern
590 systems require this timer.
593 bool "Platform Runtime Mechanism Support"
594 depends on EFI && X86_64
597 Platform Runtime Mechanism (PRM) is a firmware interface exposing a
598 set of binary executables that can be called from the AML interpreter
599 or directly from device drivers.
601 Say Y to enable the AML interpreter to execute the PRM code.
603 While this feature is optional in principle, leaving it out may
604 substantially increase computational overhead related to the
605 initialization of some server systems.