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
17 Advanced Configuration and Power Interface (ACPI) support for
18 Linux requires an ACPI-compliant platform (hardware/firmware),
19 and assumes the presence of OS-directed configuration and power
20 management (OSPM) software. This option will enlarge your
23 Linux ACPI provides a robust functional replacement for several
24 legacy configuration and power management interfaces, including
25 the Plug-and-Play BIOS specification (PnP BIOS), the
26 MultiProcessor Specification (MPS), and the Advanced Power
27 Management (APM) specification. If both ACPI and APM support
28 are configured, ACPI is used.
30 The project home page for the Linux ACPI subsystem is here:
31 <https://01.org/linux-acpi>
33 Linux support for ACPI is based on Intel Corporation's ACPI
34 Component Architecture (ACPI CA). For more information on the
38 ACPI is an open industry specification originally co-developed by
39 Hewlett-Packard, Intel, Microsoft, Phoenix, and Toshiba. Currently,
40 it is developed by the ACPI Specification Working Group (ASWG) under
41 the UEFI Forum and any UEFI member can join the ASWG and contribute
42 to the ACPI specification.
43 The specification is available at:
44 <https://uefi.org/specifications>
48 config ACPI_LEGACY_TABLES_LOOKUP
51 config ARCH_MIGHT_HAVE_ACPI_PDC
54 config ACPI_GENERIC_GSI
57 config ACPI_SYSTEM_POWER_STATES_SUPPORT
60 config ACPI_CCA_REQUIRED
67 bool "AML debugger interface"
70 Enable in-kernel debugging of AML facilities: statistics,
71 internal object dump, single step control method execution.
72 This is still under development, currently enabling this only
73 results in the compilation of the ACPICA debugger files.
77 config ACPI_DEBUGGER_USER
78 tristate "Userspace debugger accessibility"
81 Export /sys/kernel/debug/acpi/acpidbg for userspace utilities
82 to access the debugger functionalities.
86 config ACPI_SPCR_TABLE
87 bool "ACPI Serial Port Console Redirection Support"
90 Enable support for Serial Port Console Redirection (SPCR) Table.
91 This table provides information about the configuration of the
95 bool "ACPI Firmware Performance Data Table (FPDT) support"
98 Enable support for the Firmware Performance Data Table (FPDT).
99 This table provides information on the timing of the system
100 boot, S3 suspend and S3 resume firmware code paths.
109 depends on SUSPEND || HIBERNATION
110 depends on ACPI_SYSTEM_POWER_STATES_SUPPORT
113 config ACPI_REV_OVERRIDE_POSSIBLE
114 bool "Allow supported ACPI revision to be overridden"
118 The platform firmware on some systems expects Linux to return "5" as
119 the supported ACPI revision which makes it expose system configuration
120 information in a special way.
122 For example, based on what ACPI exports as the supported revision,
123 Dell XPS 13 (2015) configures its audio device to either work in HDA
124 mode or in I2S mode, where the former is supposed to be used on Linux
125 until the latter is fully supported (in the kernel as well as in user
128 This option enables a DMI-based quirk for the above Dell machine (so
129 that HDA audio is exposed by the platform firmware to the kernel) and
130 makes it possible to force the kernel to return "5" as the supported
131 ACPI revision via the "acpi_rev_override" command line switch.
133 config ACPI_EC_DEBUGFS
134 tristate "EC read/write access through /sys/kernel/debug/ec"
136 Say N to disable Embedded Controller /sys/kernel/debug interface
138 Be aware that using this interface can confuse your Embedded
139 Controller in a way that a normal reboot is not enough. You then
140 have to power off your system, and remove the laptop battery for
142 An Embedded Controller typically is available on laptops and reads
143 sensor values like battery state and temperature.
144 The kernel accesses the EC through ACPI parsed code provided by BIOS
145 tables. This option allows to access the EC directly without ACPI
147 Thus this option is a debug option that helps to write ACPI drivers
148 and can be used to identify ACPI code or EC firmware bugs.
151 tristate "AC Adapter"
155 This driver supports the AC Adapter object, which indicates
156 whether a system is on AC or not. If you have a system that can
157 switch between A/C and battery, say Y.
159 To compile this driver as a module, choose M here:
160 the module will be called ac.
167 This driver adds support for battery information through
168 /proc/acpi/battery. If you have a mobile system with a battery,
171 To compile this driver as a module, choose M here:
172 the module will be called battery.
179 This driver handles events on the power, sleep, and lid buttons.
180 A daemon reads events from input devices or via netlink and
181 performs user-defined actions such as shutting down the system.
182 This is necessary for software-controlled poweroff.
184 To compile this driver as a module, choose M here:
185 the module will be called button.
187 config ACPI_TINY_POWER_BUTTON
188 tristate "Tiny Power Button Driver"
189 depends on !ACPI_BUTTON
191 This driver provides a tiny alternative to the ACPI Button driver.
192 The tiny power button driver only handles the power button. Rather
193 than notifying userspace via the input layer or a netlink event, this
194 driver directly signals the init process to shut down.
196 This driver is particularly suitable for cloud and VM environments,
197 which use a simulated power button to initiate a controlled poweroff,
198 but which may not want to run a separate userspace daemon to process
201 config ACPI_TINY_POWER_BUTTON_SIGNAL
202 int "Tiny Power Button Signal"
203 depends on ACPI_TINY_POWER_BUTTON
206 Default signal to send to init in response to the power button.
208 Likely values here include 38 (SIGRTMIN+4) to power off, or 2
209 (SIGINT) to simulate Ctrl+Alt+Del.
213 depends on X86 && BACKLIGHT_CLASS_DEVICE
217 This driver implements the ACPI Extensions For Display Adapters
218 for integrated graphics devices on motherboard, as specified in
219 ACPI 2.0 Specification, Appendix B. This supports basic operations
220 such as defining the video POST device, retrieving EDID information,
221 and setting up a video output.
223 To compile this driver as a module, choose M here:
224 the module will be called video.
231 This driver supports ACPI fan devices, allowing user-mode
232 applications to perform basic fan control (on, off, status).
234 To compile this driver as a module, choose M here:
235 the module will be called fan.
238 tristate "ACPI Time and Alarm (TAD) Device Support"
239 depends on SYSFS && PM_SLEEP
241 The ACPI Time and Alarm (TAD) device is an alternative to the Real
242 Time Clock (RTC). Its wake timers allow the system to transition from
243 the S3 (or optionally S4/S5) state to S0 state after a time period
244 elapses. In comparison with the RTC Alarm, the TAD provides a larger
245 scale of flexibility in the wake timers. The time capabilities of the
246 TAD maintain the time of day information across platform power
247 transitions, and keep track of time even when the platform is turned
253 This driver supports ACPI-controlled docking stations and removable
254 drive bays such as the IBM Ultrabay and the Dell Module Bay.
256 config ACPI_CPU_FREQ_PSS
260 config ACPI_PROCESSOR_CSTATE
262 depends on ACPI_PROCESSOR
263 depends on IA64 || X86
265 config ACPI_PROCESSOR_IDLE
274 depends on ACPI_PROCESSOR
278 If this option is enabled, this file implements common functionality
279 to parse CPPC tables as described in the ACPI 5.1+ spec. The
280 routines implemented are meant to be used by other
281 drivers to control CPU performance using CPPC semantics.
282 If your platform does not support CPPC in firmware,
283 leave this option disabled.
285 config ACPI_PROCESSOR
287 depends on X86 || IA64 || ARM64 || LOONGARCH
288 select ACPI_PROCESSOR_IDLE
289 select ACPI_CPU_FREQ_PSS if X86 || IA64 || LOONGARCH
292 This driver adds support for the ACPI Processor package. It is required
293 by several flavors of cpufreq performance-state, thermal, throttling and
296 To compile this driver as a module, choose M here:
297 the module will be called processor.
301 depends on IPMI_HANDLER
303 This driver enables the ACPI to access the BMC controller. And it
304 uses the IPMI request/response message to communicate with BMC
305 controller, which can be found on the server.
307 To compile this driver as a module, choose M here:
308 the module will be called as acpi_ipmi.
310 config ACPI_HOTPLUG_CPU
312 depends on ACPI_PROCESSOR && HOTPLUG_CPU
313 select ACPI_CONTAINER
316 config ACPI_PROCESSOR_AGGREGATOR
317 tristate "Processor Aggregator"
318 depends on ACPI_PROCESSOR
321 ACPI 4.0 defines processor Aggregator, which enables OS to perform
322 specific processor configuration and control that applies to all
323 processors in the platform. Currently only logical processor idling
324 is defined, which is to reduce power consumption. This driver
325 supports the new device.
328 tristate "Thermal Zone"
329 depends on ACPI_PROCESSOR
333 This driver supports ACPI thermal zones. Most mobile and
334 some desktop systems support ACPI thermal zones. It is HIGHLY
335 recommended that this option be enabled, as your processor(s)
336 may be damaged without it.
338 To compile this driver as a module, choose M here:
339 the module will be called thermal.
341 config ACPI_PLATFORM_PROFILE
344 config ACPI_CUSTOM_DSDT_FILE
345 string "Custom DSDT Table file to include"
347 depends on !STANDALONE
349 This option supports a custom DSDT by linking it into the kernel.
350 See Documentation/admin-guide/acpi/dsdt-override.rst
352 Enter the full path name to the file which includes the AmlCode
353 or dsdt_aml_code declaration.
355 If unsure, don't enter a file name.
357 config ACPI_CUSTOM_DSDT
359 default ACPI_CUSTOM_DSDT_FILE != ""
361 config ARCH_HAS_ACPI_TABLE_UPGRADE
364 config ACPI_TABLE_UPGRADE
365 bool "Allow upgrading ACPI tables via initrd"
366 depends on BLK_DEV_INITRD && ARCH_HAS_ACPI_TABLE_UPGRADE
369 This option provides functionality to upgrade arbitrary ACPI tables
370 via initrd. No functional change if no ACPI tables are passed via
371 initrd, therefore it's safe to say Y.
372 See Documentation/admin-guide/acpi/initrd_table_override.rst for details
374 config ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD
375 bool "Override ACPI tables from built-in initrd"
376 depends on ACPI_TABLE_UPGRADE
377 depends on INITRAMFS_SOURCE!="" && INITRAMFS_COMPRESSION_NONE
379 This option provides functionality to override arbitrary ACPI tables
380 from built-in uncompressed initrd.
382 See Documentation/admin-guide/acpi/initrd_table_override.rst for details
385 bool "Debug Statements"
387 The ACPI subsystem can produce debug output. Saying Y enables this
388 output and increases the kernel size by around 50K.
390 Use the acpi.debug_layer and acpi.debug_level kernel command-line
391 parameters documented in Documentation/firmware-guide/acpi/debug.rst and
392 Documentation/admin-guide/kernel-parameters.rst to control the type and
393 amount of debug output.
396 bool "PCI slot detection driver"
397 depends on SYSFS && PCI
399 This driver creates entries in /sys/bus/pci/slots/ for all PCI
400 slots in the system. This can help correlate PCI bus addresses,
401 i.e., segment/bus/device/function tuples, with physical slots in
402 the system. If you are unsure, say N.
404 config ACPI_CONTAINER
405 bool "Container and Module Devices"
406 default (ACPI_HOTPLUG_MEMORY || ACPI_HOTPLUG_CPU)
408 This driver supports ACPI Container and Module devices (IDs
409 ACPI0004, PNP0A05, and PNP0A06).
411 This helps support hotplug of nodes, CPUs, and memory.
413 config ACPI_HOTPLUG_MEMORY
414 bool "Memory Hotplug"
415 depends on MEMORY_HOTPLUG
417 This driver supports ACPI memory hotplug. The driver
418 fields notifications on ACPI memory devices (PNP0C80),
419 which represent memory ranges that may be onlined or
420 offlined during runtime.
422 If your hardware and firmware do not support adding or
423 removing memory devices at runtime, you need not enable
426 config ACPI_HOTPLUG_IOAPIC
429 depends on X86_IO_APIC
433 tristate "Smart Battery System"
437 This driver supports the Smart Battery System, another
438 type of access to battery information, found on some laptops.
440 To compile this driver as a module, choose M here:
441 the modules will be called sbs and sbshc.
444 tristate "Hardware Error Device"
446 This driver supports the Hardware Error Device (PNP0C33),
447 which is used to report some hardware errors notified via
448 SCI, mainly the corrected errors.
450 config ACPI_CUSTOM_METHOD
451 tristate "Allow ACPI methods to be inserted/replaced at run time"
454 This debug facility allows ACPI AML methods to be inserted and/or
455 replaced without rebooting the system. For details refer to:
456 Documentation/firmware-guide/acpi/method-customizing.rst.
458 NOTE: This option is security sensitive, because it allows arbitrary
459 kernel memory to be written to by root (uid=0) users, allowing them
460 to bypass certain security measures (e.g. if root is not allowed to
461 load additional kernel modules after boot, this feature may be used
462 to override that restriction).
465 bool "Boottime Graphics Resource Table support"
466 depends on EFI && (X86 || ARM64)
468 This driver adds support for exposing the ACPI Boottime Graphics
469 Resource Table, which allows the operating system to obtain
470 data from the firmware boot splash. It will appear under
471 /sys/firmware/acpi/bgrt/ .
473 config ACPI_REDUCED_HARDWARE_ONLY
474 bool "Hardware-reduced ACPI support only" if EXPERT
477 This config item changes the way the ACPI code is built. When this
478 option is selected, the kernel will use a specialized version of
479 ACPICA that ONLY supports the ACPI "reduced hardware" mode. The
480 resulting kernel will be smaller but it will also be restricted to
481 running in ACPI reduced hardware mode ONLY.
483 If you are unsure what to do, do not enable this option.
485 source "drivers/acpi/nfit/Kconfig"
486 source "drivers/acpi/numa/Kconfig"
487 source "drivers/acpi/apei/Kconfig"
488 source "drivers/acpi/dptf/Kconfig"
494 tristate "Extended Error Log support"
495 depends on X86_MCE && X86_LOCAL_APIC && EDAC
498 Certain usages such as Predictive Failure Analysis (PFA) require
499 more information about the error than what can be described in
500 processor machine check banks. Most server processors log
501 additional information about the error in processor uncore
502 registers. Since the addresses and layout of these registers vary
503 widely from one processor to another, system software cannot
504 readily make use of them. To complicate matters further, some of
505 the additional error information cannot be constructed without
506 detailed knowledge about platform topology.
508 Enhanced MCA Logging allows firmware to provide additional error
509 information to system software, synchronous with MCE or CMCI. This
510 driver adds support for that functionality with corresponding
511 tracepoint which carries that information to userspace.
517 tristate "ACPI configfs support"
520 Select this option to enable support for ACPI configuration from
521 userspace. The configurable ACPI groups will be visible under
522 /config/acpi, assuming configfs is mounted under /config.
525 tristate "ACPI Platform Firmware Runtime Update and Telemetry"
528 This mechanism allows certain pieces of the platform firmware
529 to be updated on the fly while the system is running (runtime)
530 without the need to restart it, which is key in the cases when
531 the system needs to be available 100% of the time and it cannot
532 afford the downtime related to restarting it, or when the work
533 carried out by the system is particularly important, so it cannot
534 be interrupted, and it is not practical to wait until it is complete.
536 The existing firmware code can be modified (driver update) or
537 extended by adding new code to the firmware (code injection).
539 Besides, the telemetry driver allows user space to fetch telemetry
540 data from the firmware with the help of the Platform Firmware Runtime
543 To compile the drivers as modules, choose M here:
544 the modules will be called pfr_update and pfr_telemetry.
547 source "drivers/acpi/arm64/Kconfig"
554 bool "ACPI PCC Address Space"
558 The PCC Address Space also referred as PCC Operation Region pertains
559 to the region of PCC subspace that succeeds the PCC signature.
561 The PCC Operation Region works in conjunction with the PCC Table
562 (Platform Communications Channel Table). PCC subspaces that are
563 marked for use as PCC Operation Regions must not be used as PCC
564 subspaces for the standard ACPI features such as CPPC, RASF, PDTT and
565 MPST. These standard features must always use the PCC Table instead.
567 Enable this feature if you want to set up and install the PCC Address
568 Space handler to handle PCC OpRegion in the firmware.
570 source "drivers/acpi/pmic/Kconfig"
578 bool "Power Management Timer Support" if EXPERT
579 depends on X86 && (ACPI || JAILHOUSE_GUEST)
582 The Power Management Timer is available on all ACPI-capable,
583 in most cases even if ACPI is unusable or blacklisted.
585 This timing source is not affected by power management features
586 like aggressive processor idling, throttling, frequency and/or
587 voltage scaling, unlike the commonly used Time Stamp Counter
590 You should nearly always say Y here because many modern
591 systems require this timer.
594 bool "Platform Runtime Mechanism Support"
595 depends on EFI && X86_64
598 Platform Runtime Mechanism (PRM) is a firmware interface exposing a
599 set of binary executables that can be called from the AML interpreter
600 or directly from device drivers.
602 Say Y to enable the AML interpreter to execute the PRM code.
604 While this feature is optional in principle, leaving it out may
605 substantially increase computational overhead related to the
606 initialization of some server systems.