1.\" 2.\" Copyright (c) 2001 Michael Smith 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD: src/share/man/man4/acpi.4,v 1.50 2005/02/23 07:23:35 trhodes Exp $ 27.\" $DragonFly: src/share/man/man4/acpi.4,v 1.3 2005/07/03 20:58:35 asmodai Exp $ 28.\" 29.Dd February 13, 2005 30.Dt ACPI 4 31.Dx 32.Sh NAME 33.Nm acpi 34.Nd Advanced Configuration and Power Management support 35.Sh SYNOPSIS 36.Cd "device acpi" 37.Pp 38.Cd "options ACPI_DEBUG" 39.Sh DESCRIPTION 40The 41.Nm 42driver provides support for the Intel/Microsoft/Compaq/Toshiba ACPI 43standard. 44This support includes platform hardware discovery (superseding the 45PnP and PCI BIOS), as well as power management (superseding APM) and 46other features. 47ACPI core support is provided by the ACPI CA reference implementation 48from Intel. 49.Pp 50Note that the 51.Nm 52driver is automatically loaded by the 53.Xr loader 8 , 54and should only be 55compiled into the kernel on platforms where ACPI is mandatory. 56.Sh SYSCTLS 57The 58.Nm 59driver is intended to provide power management without user intervention. 60Thus, some of these sysctls are controlled automatically by the 61.Pa power_profile 62.Xr rc 8 63script, which can be configured via 64.Xr rc.conf 5 . 65If values are specified manually, they may be overridden. 66.Bl -tag -width indent 67.It Va hw.acpi.cpu.cx_usage 68Debugging information listing the percent of total usage for each sleep state. 69The values are reset when 70.Va hw.acpi.cpu.cx_lowest 71is modified. 72.It Va hw.acpi.cpu.cx_lowest 73Lowest Cx state to use for idling the CPU. 74A scheduling algorithm will select states between C1 and this setting 75as system load dictates. 76To enable ACPI CPU idling control, 77.Va machdep.cpu_idle_hlt 78must be set to 1. 79.It Va hw.acpi.cpu.cx_supported 80List of supported CPU idle states and their transition latency 81in microseconds. 82Each state has a type (e.g., C2). 83C1 is equivalent to the ia32 HLT instruction, C2 provides a deeper 84sleep with the same semantics, and C3 provides the deepest sleep 85but additionally requires bus mastering to be disabled. 86States greater than C3 provide even more power savings with the same 87semantics as the C3 state. 88Deeper sleeps provide more power savings but increased transition 89latency when an interrupt occurs. 90.El 91.Sh TUNABLES 92Tunables can be set at the 93.Xr loader 8 94prompt before booting the kernel or stored in 95.Pa /boot/loader.conf . 96.Bl -tag -width indent 97.It Va acpi_dsdt_load 98Enables loading of a custom ACPI DSDT. 99.It Va acpi_dsdt_name 100Name of the DSDT table to load, if loading is enabled. 101.It Va debug.acpi.disabled 102Selectively disables portions of ACPI for debugging purposes. 103.It Va debug.acpi.quirks 104Override any automatic quirks completely. 105.It Va hint.acpi.0.disabled 106Set this to 1 to disable all of ACPI. 107If ACPI has been disabled on your system due to a blacklist entry for your 108BIOS, you can set this to 0 to re-enable ACPI for testing. 109.It Va hw.acpi.ec.poll_timeout 110Delay in milliseconds to wait for the EC to respond. 111Try increasing this number if you get the error 112.Qq Li AE_NO_HARDWARE_RESPONSE . 113.It Va hw.acpi.host_mem_start 114Override the assumed memory starting address for PCI host bridges. 115.It Va hw.acpi.pci.link.%d.%d.%d.irq 116Override the interrupt to use. 117.It Va hw.acpi.reset_video 118Enables calling the VESA reset BIOS vector on the resume path. 119Some graphic chips have problems such as LCD white-out after resume. 120Try setting this to 0 if this causes problems for you. 121.It Va hw.acpi.serialize_methods 122Allow override of whether methods execute in parallel or not. 123Enable this for serial behavior, which fixes 124.Qq Li AE_ALREADY_EXISTS 125errors for 126AML that really cannot handle parallel method execution. 127It is off by default since this breaks recursive methods and some IBMs use 128such code. 129.It Va hw.acpi.verbose 130Turn on verbose debugging information about what ACPI is doing. 131.El 132.Sh DISABLING ACPI 133Since ACPI support on different platforms varies greatly, there are many 134debugging and tuning options available. 135.Pp 136For machines known not to work with 137.Nm 138enabled, there is a BIOS blacklist. 139Currently, the blacklist only controls whether 140.Nm 141should be disabled or not. 142In the future, it will have more granularity to control features (the 143infrastructure for that is already there). 144.Pp 145To enable 146.Nm 147(for debugging purposes, etc.) on machines that are on the blacklist, set the 148kernel environment variable 149.Va hint.acpi.0.disabled 150to 0. 151Before trying this, consider updating your BIOS to a more recent version that 152may be compatible with ACPI. 153.Pp 154To disable the 155.Nm 156driver completely, set the kernel environment variable 157.Va hint.acpi.0.disabled 158to 1. 159.Pp 160Some i386 machines totally fail to operate with some or all of ACPI disabled. 161Other i386 machines fail with ACPI enabled. 162Disabling all or part of ACPI on non-i386 platforms (i.e., platforms where 163ACPI support is mandatory) may result in a non-functional system. 164.Pp 165The 166.Nm 167driver comprises a set of drivers, which may be selectively disabled 168in case of problems. 169To disable a sub-driver, list it in the kernel 170environment variable 171.Va debug.acpi.disabled . 172Multiple entries can be listed, separated by a space. 173.Pp 174ACPI sub-devices and features that can be disabled: 175.Bl -tag -width ".Li sysresource" 176.It Li all 177Disable all ACPI features and devices. 178.It Li acad 179.Pq Vt device 180Supports AC adapter. 181.It Li bus 182.Pq Vt feature 183Probes and attaches subdevices. 184Disabling will avoid scanning the ACPI namespace entirely. 185.It Li children 186.Pq Vt feature 187Attaches standard ACPI sub-drivers and devices enumerated in the 188ACPI namespace. 189Disabling this has a similar effect to disabling 190.Dq Li bus , 191except that the 192ACPI namespace will still be scanned. 193.It Li button 194.Pq Vt device 195Supports ACPI button devices (typically power and sleep buttons). 196.It Li cmbat 197.Pq Vt device 198Control-method batteries device. 199.It Li cpu 200.Pq Vt device 201Supports CPU power-saving and speed-setting functions. 202.It Li ec 203.Pq Vt device 204Supports the ACPI Embedded Controller interface, used to communicate 205with embedded platform controllers. 206.It Li isa 207.Pq Vt device 208Supports an ISA bus bridge defined in the ACPI namespace, 209typically as a child of a PCI bus. 210.It Li lid 211.Pq Vt device 212Supports an ACPI laptop lid switch, which typically puts a 213system to sleep. 214.It Li quirks 215.Pq Vt feature 216Do not honor quirks. 217Quirks automatically disable ACPI functionality based on the XSDT table's 218OEM vendor name and revision date. 219.It Li pci 220.Pq Vt device 221Supports Host to PCI bridges. 222.It Li pci_link 223.Pq Vt feature 224Performs PCI interrupt routing. 225.It Li sysresource 226.Pq Vt device 227Pseudo-devices containing resources which ACPI claims. 228.It Li thermal 229.Pq Vt device 230Supports system cooling and heat management. 231.It Li timer 232.Pq Vt device 233Implements a timecounter using the ACPI fixed-frequency timer. 234.It Li video 235.Pq Vt device 236Supports acpi_video which may conflict with agp device. 237.El 238.Pp 239It is also possible to avoid portions of the ACPI namespace which 240may be causing problems, by listing the full path of the root of 241the region to be avoided in the kernel environment variable 242.Va debug.acpi.avoid.paths , 243or 244.Va debug.acpi.avoid . 245The latter also disables initialization of ACPI namespace as a 246workaround for systems where not doing so crashes interpreter. 247The object and all of its children will be ignored during the 248bus/children scan of the namespace. 249The ACPI CA code will still know about the avoided region. 250.Sh DEBUGGING OUTPUT 251To enable debugging output, 252.Nm 253must be compiled with 254.Cd "options ACPI_DEBUG" . 255Debugging output is separated between layers and levels, where a layer is 256a component of the ACPI subsystem, and a level is a particular kind 257of debugging output. 258.Pp 259Both layers and levels are specified as a whitespace-separated list of 260tokens, with layers listed in 261.Va debug.acpi.layer 262and levels in 263.Va debug.acpi.level . 264.Pp 265The first set of layers is for ACPI-CA components, and the second is for 266.Dx 267drivers. 268The ACPI-CA layer descriptions include the prefix for the files they 269refer to. 270The supported layers are: 271.Pp 272.Bl -tag -compact -width ".Li ACPI_CA_DISASSEMBLER" 273.It Li ACPI_UTILITIES 274Utility ("ut") functions 275.It Li ACPI_HARDWARE 276Hardware access ("hw") 277.It Li ACPI_EVENTS 278Event and GPE ("ev") 279.It Li ACPI_TABLES 280Table access ("tb") 281.It Li ACPI_NAMESPACE 282Namespace evaluation ("ns") 283.It Li ACPI_PARSER 284AML parser ("ps") 285.It Li ACPI_DISPATCHER 286Internal representation of interpreter state ("ds") 287.It Li ACPI_EXECUTER 288Execute AML methods ("ex") 289.It Li ACPI_RESOURCES 290Resource parsing ("rs") 291.It Li ACPI_CA_DEBUGGER 292Debugger implementation ("db", "dm") 293.It Li ACPI_OS_SERVICES 294Usermode support routines ("os") 295.It Li ACPI_CA_DISASSEMBLER 296Disassembler implementation (unused) 297.It Li ACPI_ALL_COMPONENTS 298All the above ACPI-CA components 299.It Li ACPI_AC_ADAPTER 300AC adapter driver 301.It Li ACPI_BATTERY 302Control-method battery driver 303.It Li ACPI_BUS 304ACPI, ISA, and PCI bus drivers 305.It Li ACPI_BUTTON 306Power and sleep button driver 307.It Li ACPI_EC 308Embedded controller driver 309.It Li ACPI_FAN 310Fan driver 311.It Li ACPI_OEM 312Platform-specific driver for hotkeys, LED, etc. 313.It Li ACPI_POWER 314Power resource driver 315.It Li ACPI_PROCESSOR 316CPU driver 317.It Li ACPI_THERMAL 318Thermal zone driver 319.It Li ACPI_TIMER 320Timer driver 321.It Li ACPI_ALL_DRIVERS 322All the above 323.Dx 324ACPI drivers 325.El 326.Pp 327The supported levels are: 328.Pp 329.Bl -tag -compact -width ".Li ACPI_LV_AML_DISASSEMBLE" 330.It Li ACPI_LV_ERROR 331Fatal error conditions 332.It Li ACPI_LV_WARN 333Warnings and potential problems 334.It Li ACPI_LV_INIT 335Initialization progress 336.It Li ACPI_LV_DEBUG_OBJECT 337Stores to objects 338.It Li ACPI_LV_INFO 339General information and progress 340.It Li ACPI_LV_ALL_EXCEPTIONS 341All the previous levels 342.It Li ACPI_LV_INIT_NAMES 343.It Li ACPI_LV_PARSE 344.It Li ACPI_LV_LOAD 345.It Li ACPI_LV_DISPATCH 346.It Li ACPI_LV_EXEC 347.It Li ACPI_LV_NAMES 348.It Li ACPI_LV_OPREGION 349.It Li ACPI_LV_BFIELD 350.It Li ACPI_LV_TABLES 351.It Li ACPI_LV_VALUES 352.It Li ACPI_LV_OBJECTS 353.It Li ACPI_LV_RESOURCES 354.It Li ACPI_LV_USER_REQUESTS 355.It Li ACPI_LV_PACKAGE 356.It Li ACPI_LV_VERBOSITY1 357All the previous levels 358.It Li ACPI_LV_ALLOCATIONS 359.It Li ACPI_LV_FUNCTIONS 360.It Li ACPI_LV_OPTIMIZATIONS 361.It Li ACPI_LV_VERBOSITY2 362.It Li ACPI_LV_ALL 363.It Li ACPI_LV_MUTEX 364.It Li ACPI_LV_THREADS 365.It Li ACPI_LV_IO 366.It Li ACPI_LV_INTERRUPTS 367.It Li ACPI_LV_VERBOSITY3 368All the previous levels 369.It Li ACPI_LV_AML_DISASSEMBLE 370.It Li ACPI_LV_VERBOSE_INFO 371.It Li ACPI_LV_FULL_TABLES 372.It Li ACPI_LV_EVENTS 373.It Li ACPI_LV_VERBOSE 374All levels after 375.Qq Li ACPI_LV_VERBOSITY3 376.El 377.Pp 378Selection of the appropriate layer and level values is important 379to avoid massive amounts of debugging output. 380For example, the following configuration is a good way to gather initial 381information. 382It enables debug output for both ACPI-CA and the 383.Nm 384driver, printing basic information about errors, warnings, and progress. 385.Bd -literal -offset indent 386debug.acpi.layer="ACPI_ALL_COMPONENTS ACPI_ALL_DRIVERS" 387debug.acpi.level="ACPI_LV_ALL_EXCEPTIONS" 388.Ed 389.Pp 390Debugging output by the ACPI CA subsystem is prefixed with the 391module name in lowercase, followed by a source line number. 392Output from the 393.Dx Ns -local 394code follows the same format, but 395the module name is uppercased. 396.Sh OVERRIDING YOUR BIOS BYTECODE 397ACPI interprets bytecode named AML 398(ACPI Machine Language) 399provided by the BIOS vendor as a memory image at boot time. 400Sometimes, the AML code contains a bug that does not appear when parsed 401by the Microsoft implementation. 402.Dx 403provides a way to override it with your own AML code to work around 404or debug such problems. 405Note that all AML in your DSDT and any SSDT tables is overridden. 406.Pp 407In order to load your AML code, you must edit 408.Pa /boot/loader.conf 409and include the following lines. 410.Bd -literal -offset indent 411acpi_dsdt_load="YES" 412acpi_dsdt_name="/boot/acpi_dsdt.aml" # You may change this name. 413.Ed 414.Pp 415In order to prepare your AML code, you will need the 416.Xr acpidump 8 417and 418.Xr iasl 8 419utilities and some ACPI knowledge. 420.Sh COMPATIBILITY 421ACPI is only found and supported on i386/ia32, ia64, and amd64. 422.Sh SEE ALSO 423.Xr kenv 1 , 424.Xr acpi_thermal 4 , 425.Xr device.hints 5 , 426.Xr loader.conf 5 , 427.Xr acpiconf 8 , 428.Xr acpidump 8 , 429.Xr config 8 , 430.Xr iasl 8 431.Rs 432.%A "Compaq Computer Corporation" 433.%A "Intel Corporation" 434.%A "Microsoft Corporation" 435.%A "Phoenix Technologies Ltd." 436.%A "Toshiba Corporation" 437.%D August 25, 2003 438.%T "Advanced Configuration and Power Interface Specification" 439.%O http://acpi.info/spec.htm 440.Re 441.Sh AUTHORS 442.An -nosplit 443The ACPI CA subsystem is developed and maintained by 444Intel Architecture Labs. 445.Pp 446The following people made notable contributions to the ACPI subsystem 447in 448.Dx : 449.An Michael Smith , 450.An Takanori Watanabe Aq takawata@jp.FreeBSD.org , 451.An Mitsuru IWASAKI Aq iwasaki@jp.FreeBSD.org , 452.An Munehiro Matsuda , 453.An Nate Lawson , 454the ACPI-jp mailing list at 455.Aq acpi-jp@jp.FreeBSD.org , 456and many other contributors. 457.Pp 458This manual page was written by 459.An Michael Smith Aq msmith@FreeBSD.org . 460.Sh BUGS 461If the 462.Nm 463driver is loaded as a module when it is already linked as part of the 464kernel, odd things may happen. 465