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 Linux support for ACPI is based on Intel Corporation's ACPI
31 Component Architecture (ACPI CA). For more information on the
35 ACPI is an open industry specification originally co-developed by
36 Hewlett-Packard, Intel, Microsoft, Phoenix, and Toshiba. Currently,
37 it is developed by the ACPI Specification Working Group (ASWG) under
38 the UEFI Forum and any UEFI member can join the ASWG and contribute
39 to the ACPI specification.
40 The specification is available at:
41 <https://uefi.org/specifications>
45 config ACPI_LEGACY_TABLES_LOOKUP
48 config ARCH_MIGHT_HAVE_ACPI_PDC
51 config ACPI_GENERIC_GSI
54 config ACPI_SYSTEM_POWER_STATES_SUPPORT
57 config ACPI_CCA_REQUIRED
64 bool "AML debugger interface"
67 Enable in-kernel debugging of AML facilities: statistics,
68 internal object dump, single step control method execution.
69 This is still under development, currently enabling this only
70 results in the compilation of the ACPICA debugger files.
74 config ACPI_DEBUGGER_USER
75 tristate "Userspace debugger accessibility"
78 Export /sys/kernel/debug/acpi/acpidbg for userspace utilities
79 to access the debugger functionalities.
83 config ACPI_SPCR_TABLE
84 bool "ACPI Serial Port Console Redirection Support"
87 Enable support for Serial Port Console Redirection (SPCR) Table.
88 This table provides information about the configuration of the
92 bool "ACPI Firmware Performance Data Table (FPDT) support"
95 Enable support for the Firmware Performance Data Table (FPDT).
96 This table provides information on the timing of the system
97 boot, S3 suspend and S3 resume firmware code paths.
106 depends on SUSPEND || HIBERNATION
107 depends on ACPI_SYSTEM_POWER_STATES_SUPPORT
110 config ACPI_REV_OVERRIDE_POSSIBLE
111 bool "Allow supported ACPI revision to be overridden"
115 The platform firmware on some systems expects Linux to return "5" as
116 the supported ACPI revision which makes it expose system configuration
117 information in a special way.
119 For example, based on what ACPI exports as the supported revision,
120 Dell XPS 13 (2015) configures its audio device to either work in HDA
121 mode or in I2S mode, where the former is supposed to be used on Linux
122 until the latter is fully supported (in the kernel as well as in user
125 This option enables a DMI-based quirk for the above Dell machine (so
126 that HDA audio is exposed by the platform firmware to the kernel) and
127 makes it possible to force the kernel to return "5" as the supported
128 ACPI revision via the "acpi_rev_override" command line switch.
130 config ACPI_EC_DEBUGFS
131 tristate "EC read/write access through /sys/kernel/debug/ec"
133 Say N to disable Embedded Controller /sys/kernel/debug interface
135 Be aware that using this interface can confuse your Embedded
136 Controller in a way that a normal reboot is not enough. You then
137 have to power off your system, and remove the laptop battery for
139 An Embedded Controller typically is available on laptops and reads
140 sensor values like battery state and temperature.
141 The kernel accesses the EC through ACPI parsed code provided by BIOS
142 tables. This option allows to access the EC directly without ACPI
144 Thus this option is a debug option that helps to write ACPI drivers
145 and can be used to identify ACPI code or EC firmware bugs.
148 tristate "AC Adapter"
152 This driver supports the AC Adapter object, which indicates
153 whether a system is on AC or not. If you have a system that can
154 switch between A/C and battery, say Y.
156 To compile this driver as a module, choose M here:
157 the module will be called ac.
164 This driver adds support for battery information through
165 /proc/acpi/battery. If you have a mobile system with a battery,
168 To compile this driver as a module, choose M here:
169 the module will be called battery.
176 This driver handles events on the power, sleep, and lid buttons.
177 A daemon reads events from input devices or via netlink and
178 performs user-defined actions such as shutting down the system.
179 This is necessary for software-controlled poweroff.
181 To compile this driver as a module, choose M here:
182 the module will be called button.
184 config ACPI_TINY_POWER_BUTTON
185 tristate "Tiny Power Button Driver"
186 depends on !ACPI_BUTTON
188 This driver provides a tiny alternative to the ACPI Button driver.
189 The tiny power button driver only handles the power button. Rather
190 than notifying userspace via the input layer or a netlink event, this
191 driver directly signals the init process to shut down.
193 This driver is particularly suitable for cloud and VM environments,
194 which use a simulated power button to initiate a controlled poweroff,
195 but which may not want to run a separate userspace daemon to process
198 config ACPI_TINY_POWER_BUTTON_SIGNAL
199 int "Tiny Power Button Signal"
200 depends on ACPI_TINY_POWER_BUTTON
203 Default signal to send to init in response to the power button.
205 Likely values here include 38 (SIGRTMIN+4) to power off, or 2
206 (SIGINT) to simulate Ctrl+Alt+Del.
210 depends on BACKLIGHT_CLASS_DEVICE
212 depends on ACPI_WMI || !X86
215 This driver implements the ACPI Extensions For Display Adapters
216 for integrated graphics devices on motherboard, as specified in
217 ACPI 2.0 Specification, Appendix B. This supports basic operations
218 such as defining the video POST device, retrieving EDID information,
219 and setting up a video output.
221 To compile this driver as a module, choose M here:
222 the module will be called video.
229 This driver supports ACPI fan devices, allowing user-mode
230 applications to perform basic fan control (on, off, status).
232 To compile this driver as a module, choose M here:
233 the module will be called fan.
236 tristate "ACPI Time and Alarm (TAD) Device Support"
237 depends on SYSFS && PM_SLEEP
239 The ACPI Time and Alarm (TAD) device is an alternative to the Real
240 Time Clock (RTC). Its wake timers allow the system to transition from
241 the S3 (or optionally S4/S5) state to S0 state after a time period
242 elapses. In comparison with the RTC Alarm, the TAD provides a larger
243 scale of flexibility in the wake timers. The time capabilities of the
244 TAD maintain the time of day information across platform power
245 transitions, and keep track of time even when the platform is turned
251 This driver supports ACPI-controlled docking stations and removable
252 drive bays such as the IBM Ultrabay and the Dell Module Bay.
254 config ACPI_CPU_FREQ_PSS
257 config ACPI_PROCESSOR_CSTATE
259 depends on ACPI_PROCESSOR
260 depends on IA64 || X86
262 config ACPI_PROCESSOR_IDLE
271 depends on ACPI_PROCESSOR
275 If this option is enabled, this file implements common functionality
276 to parse CPPC tables as described in the ACPI 5.1+ spec. The
277 routines implemented are meant to be used by other
278 drivers to control CPU performance using CPPC semantics.
279 If your platform does not support CPPC in firmware,
280 leave this option disabled.
282 config ACPI_PROCESSOR
284 depends on X86 || IA64 || ARM64 || LOONGARCH
285 select ACPI_PROCESSOR_IDLE
286 select ACPI_CPU_FREQ_PSS if X86 || IA64 || LOONGARCH
290 This driver adds support for the ACPI Processor package. It is required
291 by several flavors of cpufreq performance-state, thermal, throttling and
294 To compile this driver as a module, choose M here:
295 the module will be called processor.
299 depends on IPMI_HANDLER
301 This driver enables the ACPI to access the BMC controller. And it
302 uses the IPMI request/response message to communicate with BMC
303 controller, which can be found on the server.
305 To compile this driver as a module, choose M here:
306 the module will be called as acpi_ipmi.
308 config ACPI_HOTPLUG_CPU
310 depends on ACPI_PROCESSOR && HOTPLUG_CPU
311 select ACPI_CONTAINER
314 config ACPI_PROCESSOR_AGGREGATOR
315 tristate "Processor Aggregator"
316 depends on ACPI_PROCESSOR
319 ACPI 4.0 defines processor Aggregator, which enables OS to perform
320 specific processor configuration and control that applies to all
321 processors in the platform. Currently only logical processor idling
322 is defined, which is to reduce power consumption. This driver
323 supports the new device.
326 tristate "Thermal Zone"
327 depends on ACPI_PROCESSOR
331 This driver supports ACPI thermal zones. Most mobile and
332 some desktop systems support ACPI thermal zones. It is HIGHLY
333 recommended that this option be enabled, as your processor(s)
334 may be damaged without it.
336 To compile this driver as a module, choose M here:
337 the module will be called thermal.
339 config ACPI_PLATFORM_PROFILE
342 config ACPI_CUSTOM_DSDT_FILE
343 string "Custom DSDT Table file to include"
345 depends on !STANDALONE
347 This option supports a custom DSDT by linking it into the kernel.
349 Enter the full path name to the file which includes the AmlCode
350 or dsdt_aml_code declaration.
352 If unsure, don't enter a file name.
354 config ACPI_CUSTOM_DSDT
356 default ACPI_CUSTOM_DSDT_FILE != ""
358 config ARCH_HAS_ACPI_TABLE_UPGRADE
361 config ACPI_TABLE_UPGRADE
362 bool "Allow upgrading ACPI tables via initrd"
363 depends on BLK_DEV_INITRD && ARCH_HAS_ACPI_TABLE_UPGRADE
366 This option provides functionality to upgrade arbitrary ACPI tables
367 via initrd. No functional change if no ACPI tables are passed via
368 initrd, therefore it's safe to say Y.
369 See Documentation/admin-guide/acpi/initrd_table_override.rst for details
371 config ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD
372 bool "Override ACPI tables from built-in initrd"
373 depends on ACPI_TABLE_UPGRADE
374 depends on INITRAMFS_SOURCE!="" && INITRAMFS_COMPRESSION_NONE
376 This option provides functionality to override arbitrary ACPI tables
377 from built-in uncompressed initrd.
379 See Documentation/admin-guide/acpi/initrd_table_override.rst for details
382 bool "Debug Statements"
384 The ACPI subsystem can produce debug output. Saying Y enables this
385 output and increases the kernel size by around 50K.
387 Use the acpi.debug_layer and acpi.debug_level kernel command-line
388 parameters documented in Documentation/firmware-guide/acpi/debug.rst and
389 Documentation/admin-guide/kernel-parameters.rst to control the type and
390 amount of debug output.
393 bool "PCI slot detection driver"
394 depends on SYSFS && PCI
396 This driver creates entries in /sys/bus/pci/slots/ for all PCI
397 slots in the system. This can help correlate PCI bus addresses,
398 i.e., segment/bus/device/function tuples, with physical slots in
399 the system. If you are unsure, say N.
401 config ACPI_CONTAINER
402 bool "Container and Module Devices"
403 default (ACPI_HOTPLUG_MEMORY || ACPI_HOTPLUG_CPU)
405 This driver supports ACPI Container and Module devices (IDs
406 ACPI0004, PNP0A05, and PNP0A06).
408 This helps support hotplug of nodes, CPUs, and memory.
410 config ACPI_HOTPLUG_MEMORY
411 bool "Memory Hotplug"
412 depends on MEMORY_HOTPLUG
414 This driver supports ACPI memory hotplug. The driver
415 fields notifications on ACPI memory devices (PNP0C80),
416 which represent memory ranges that may be onlined or
417 offlined during runtime.
419 If your hardware and firmware do not support adding or
420 removing memory devices at runtime, you need not enable
423 config ACPI_HOTPLUG_IOAPIC
426 depends on X86_IO_APIC
430 tristate "Smart Battery System"
434 This driver supports the Smart Battery System, another
435 type of access to battery information, found on some laptops.
437 To compile this driver as a module, choose M here:
438 the modules will be called sbs and sbshc.
441 tristate "Hardware Error Device"
443 This driver supports the Hardware Error Device (PNP0C33),
444 which is used to report some hardware errors notified via
445 SCI, mainly the corrected errors.
447 config ACPI_CUSTOM_METHOD
448 tristate "Allow ACPI methods to be inserted/replaced at run time"
451 This debug facility allows ACPI AML methods to be inserted and/or
452 replaced without rebooting the system. For details refer to:
453 Documentation/firmware-guide/acpi/method-customizing.rst.
455 NOTE: This option is security sensitive, because it allows arbitrary
456 kernel memory to be written to by root (uid=0) users, allowing them
457 to bypass certain security measures (e.g. if root is not allowed to
458 load additional kernel modules after boot, this feature may be used
459 to override that restriction).
462 bool "Boottime Graphics Resource Table support"
463 depends on EFI && (X86 || ARM64)
465 This driver adds support for exposing the ACPI Boottime Graphics
466 Resource Table, which allows the operating system to obtain
467 data from the firmware boot splash. It will appear under
468 /sys/firmware/acpi/bgrt/ .
470 config ACPI_REDUCED_HARDWARE_ONLY
471 bool "Hardware-reduced ACPI support only" if EXPERT
474 This config item changes the way the ACPI code is built. When this
475 option is selected, the kernel will use a specialized version of
476 ACPICA that ONLY supports the ACPI "reduced hardware" mode. The
477 resulting kernel will be smaller but it will also be restricted to
478 running in ACPI reduced hardware mode ONLY.
480 If you are unsure what to do, do not enable this option.
482 source "drivers/acpi/nfit/Kconfig"
483 source "drivers/acpi/numa/Kconfig"
484 source "drivers/acpi/apei/Kconfig"
485 source "drivers/acpi/dptf/Kconfig"
491 tristate "Extended Error Log support"
492 depends on X86_MCE && X86_LOCAL_APIC && EDAC
495 Certain usages such as Predictive Failure Analysis (PFA) require
496 more information about the error than what can be described in
497 processor machine check banks. Most server processors log
498 additional information about the error in processor uncore
499 registers. Since the addresses and layout of these registers vary
500 widely from one processor to another, system software cannot
501 readily make use of them. To complicate matters further, some of
502 the additional error information cannot be constructed without
503 detailed knowledge about platform topology.
505 Enhanced MCA Logging allows firmware to provide additional error
506 information to system software, synchronous with MCE or CMCI. This
507 driver adds support for that functionality with corresponding
508 tracepoint which carries that information to userspace.
514 tristate "ACPI configfs support"
517 Select this option to enable support for ACPI configuration from
518 userspace. The configurable ACPI groups will be visible under
519 /config/acpi, assuming configfs is mounted under /config.
522 tristate "ACPI Platform Firmware Runtime Update and Telemetry"
525 This mechanism allows certain pieces of the platform firmware
526 to be updated on the fly while the system is running (runtime)
527 without the need to restart it, which is key in the cases when
528 the system needs to be available 100% of the time and it cannot
529 afford the downtime related to restarting it, or when the work
530 carried out by the system is particularly important, so it cannot
531 be interrupted, and it is not practical to wait until it is complete.
533 The existing firmware code can be modified (driver update) or
534 extended by adding new code to the firmware (code injection).
536 Besides, the telemetry driver allows user space to fetch telemetry
537 data from the firmware with the help of the Platform Firmware Runtime
540 To compile the drivers as modules, choose M here:
541 the modules will be called pfr_update and pfr_telemetry.
544 source "drivers/acpi/arm64/Kconfig"
551 bool "ACPI PCC Address Space"
555 The PCC Address Space also referred as PCC Operation Region pertains
556 to the region of PCC subspace that succeeds the PCC signature.
558 The PCC Operation Region works in conjunction with the PCC Table
559 (Platform Communications Channel Table). PCC subspaces that are
560 marked for use as PCC Operation Regions must not be used as PCC
561 subspaces for the standard ACPI features such as CPPC, RASF, PDTT and
562 MPST. These standard features must always use the PCC Table instead.
564 Enable this feature if you want to set up and install the PCC Address
565 Space handler to handle PCC OpRegion in the firmware.
567 source "drivers/acpi/pmic/Kconfig"
573 bool "Platform Runtime Mechanism Support"
574 depends on EFI && (X86_64 || ARM64)
577 Platform Runtime Mechanism (PRM) is a firmware interface exposing a
578 set of binary executables that can be called from the AML interpreter
579 or directly from device drivers.
581 Say Y to enable the AML interpreter to execute the PRM code.
583 While this feature is optional in principle, leaving it out may
584 substantially increase computational overhead related to the
585 initialization of some server systems.
590 bool "Power Management Timer Support" if EXPERT
591 depends on X86 && (ACPI || JAILHOUSE_GUEST)
594 The Power Management Timer is available on all ACPI-capable,
595 in most cases even if ACPI is unusable or blacklisted.
597 This timing source is not affected by power management features
598 like aggressive processor idling, throttling, frequency and/or
599 voltage scaling, unlike the commonly used Time Stamp Counter
602 You should nearly always say Y here because many modern
603 systems require this timer.