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.\" $FreeBSD$ 27.\" 28.Dd July 2, 2001 29.Dt ACPI 4 30.Os 31.Sh NAME 32.Nm acpi 33.Nd Advanced Configuration and Power Management support 34.Sh SYNOPSIS 35.Cd "device acpi" 36.Pp 37.Cd "options ACPI_DEBUG" 38.Sh DESCRIPTION 39The 40.Nm 41driver provides support for the Intel/Microsoft/Compaq/Toshiba ACPI 42standard. 43This support includes platform hardware discovery (superseding the 44PnP and PCI BIOS), as well as power management (superseding APM) and 45other features. 46ACPI core support is provided by the ACPI CA reference implementation 47from Intel. 48.Pp 49Note that the 50.Nm 51driver is automatically loaded by the bootloader, and should not normally 52be compiled into the kernel. 53.Sh ENVIRONMENT 54This support is still experimental, and thus there are many debugging 55and tuning options which are managed via the kernel environment. 56Tunables can be set at the 57.Xr loader 8 58prompt before booting the kernel or stored in 59.Pa /boot/loader.conf . 60.Pp 61Debugging is separated between layers and levels, where a layer is 62a portion of the ACPI subsystem, and a level is a particular kind 63of debugging output. 64.Pp 65Both layers and levels are specified as a whitespace-separated list of 66tokens, with layers listed in 67.Va debug.acpi.layer 68and levels in 69.Va debug.acpi.level . 70The supported layers are: 71.Pp 72.Bl -item -offset indent -compact 73.It 74.Li ACPI_UTILITIES 75.It 76.Li ACPI_HARDWARE 77.It 78.Li ACPI_EVENTS 79.It 80.Li ACPI_TABLES 81.It 82.Li ACPI_NAMESPACE 83.It 84.Li ACPI_PARSER 85.It 86.Li ACPI_DISPATCHER 87.It 88.Li ACPI_EXECUTER 89.It 90.Li ACPI_RESOURCES 91.It 92.Li ACPI_CA_DEBUGGER 93.It 94.Li ACPI_OS_SERVICES 95.It 96.Li ACPI_CA_DISASSEMBLER 97.It 98.Li ACPI_ALL_COMPONENTS 99.It 100.Li ACPI_AC_ADAPTER 101.It 102.Li ACPI_BATTERY 103.It 104.Li ACPI_BUS 105.It 106.Li ACPI_BUTTON 107.It 108.Li ACPI_EC 109.It 110.Li ACPI_FAN 111.It 112.Li ACPI_POWER 113.It 114.Li ACPI_PROCESSOR 115.It 116.Li ACPI_THERMAL 117.It 118.Li ACPI_TIMER 119.It 120.Li ACPI_ALL_DRIVERS 121.El 122.Pp 123The supported levels are: 124.Pp 125.Bl -item -offset indent -compact 126.It 127.Li ACPI_LV_ERROR 128.It 129.Li ACPI_LV_WARN 130.It 131.Li ACPI_LV_INIT 132.It 133.Li ACPI_LV_DEBUG_OBJECT 134.It 135.Li ACPI_LV_INFO 136.It 137.Li ACPI_LV_ALL_EXCEPTIONS 138.It 139.Li ACPI_LV_INIT_NAMES 140.It 141.Li ACPI_LV_PARSE 142.It 143.Li ACPI_LV_LOAD 144.It 145.Li ACPI_LV_DISPATCH 146.It 147.Li ACPI_LV_EXEC 148.It 149.Li ACPI_LV_NAMES 150.It 151.Li ACPI_LV_OPREGION 152.It 153.Li ACPI_LV_BFIELD 154.It 155.Li ACPI_LV_TABLES 156.It 157.Li ACPI_LV_VALUES 158.It 159.Li ACPI_LV_OBJECTS 160.It 161.Li ACPI_LV_RESOURCES 162.It 163.Li ACPI_LV_USER_REQUESTS 164.It 165.Li ACPI_LV_PACKAGE 166.It 167.Li ACPI_LV_VERBOSITY1 168.It 169.Li ACPI_LV_ALLOCATIONS 170.It 171.Li ACPI_LV_FUNCTIONS 172.It 173.Li ACPI_LV_OPTIMIZATIONS 174.It 175.Li ACPI_LV_VERBOSITY2 176.It 177.Li ACPI_LV_ALL 178.It 179.Li ACPI_LV_MUTEX 180.It 181.Li ACPI_LV_THREADS 182.It 183.Li ACPI_LV_IO 184.It 185.Li ACPI_LV_INTERRUPTS 186.It 187.Li ACPI_LV_VERBOSITY3 188.It 189.Li ACPI_LV_AML_DISASSEMBLE 190.It 191.Li ACPI_LV_VERBOSE_INFO 192.It 193.Li ACPI_LV_FULL_TABLES 194.It 195.Li ACPI_LV_EVENTS 196.It 197.Li ACPI_LV_VERBOSE 198.El 199.Pp 200Selection of the appropriate layer and level values is important 201to avoid massive amounts of debugging output. 202Check the code to see which you need. 203.Pp 204Debugging output by the ACPI CA subsystem is prefixed with the 205module name in lowercase, followed by a source line number. 206Output from the 207.Fx Ns -local 208code follows the same format, but 209the module name is uppercased. 210.Pp 211To disable the 212.Nm 213driver completely, set the kernel environment variable 214.Va hint.acpi.0.disabled 215to 1. 216.Pp 217Some i386 machines totally fail to operate with some or all of ACPI disabled. 218Other i386 machines fail with ACPI enabled. 219Non-i386 platforms do not support operating systems which do not use ACPI. 220Disabling all or part of ACPI on non-i386 platforms may result in a 221non-functional system. 222.Pp 223The 224.Nm 225driver comprises a set of drivers, which may be selectively disabled 226in case of problems. 227To disable a sub-driver, list it in the kernel 228environment variable 229.Va debug.acpi.disabled . 230Multiple entries can be listed, separated by a space. 231.Pp 232ACPI sub-devices and features that can be disabled: 233.Bl -tag -width sysresource 234.It Li all 235Disable all ACPI features and devices. 236.It Li acad 237.Pq Vt device 238Supports AC adapter. 239.It Li bus 240.Pq Vt feature 241Probes and attaches subdevices. 242Disabling will avoid scanning the ACPI namespace entirely. 243.It Li children 244.Pq Vt feature 245Attaches standard ACPI sub-drivers and devices enumerated in the 246ACPI namespace. 247Disabling this has a similar effect to disabling 248.Dq Li bus , 249except that the 250ACPI namespace will still be scanned. 251.It Li button 252.Pq Vt device 253Supports ACPI button devices (typically power and sleep buttons.) 254.It Li cmbat 255.Pq Vt device 256Control-method batteries device. 257.It Li cpu 258.Pq Vt device 259Supports CPU power-saving and speed-setting functions. 260.It Li ec 261.Pq Vt device 262Supports the ACPI Embedded Controller interface, used to communicate 263with embedded platform controllers. 264.It Li isa 265.Pq Vt device 266Supports an ISA bus bridge defined in the ACPI namespace, 267typically as a child of a PCI bus. 268.It Li lid 269.Pq Vt device 270Supports an ACPI laptop lid switch, which typically puts a 271system to sleep. 272.It Li quirks 273.Pq Vt feature 274Don't honor quirks. 275Quirks automatically disable ACPI functionality based on the XSDT table's 276OEM vendor name and revision date. 277.It Li pci 278.Pq Vt device 279Supports Host to PCI bridges. 280.It Li pci_link 281.Pq Vt feature 282Performs PCI interrupt routing. 283.It Li sysresource 284.Pq Vt device 285Pseudo-devices containing resources which ACPI claims. 286.It Li thermal 287.Pq Vt device 288Supports system cooling and heat management. 289.It Li timer 290.Pq Vt device 291Implements a timecounter using the ACPI fixed-frequency timer. 292.El 293.Pp 294It is also possible to avoid portions of the ACPI namespace which 295may be causing problems, by listing the full path of the root of 296the region to be avoided in the kernel environment variable 297.Va debug.acpi.avoid . 298The object and all of its children will be ignored during the 299bus/children scan of the namespace. 300The ACPI CA code will still 301know about the avoided region. 302.Sh OVERRIDING YOUR BIOS BYTECODE 303ACPI interprets bytecode named AML, ACPI Machine Language, provided by the BIOS 304vendor as a memory image at boot time. 305Sometimes, the AML code contains 306a problem that does not appear in the Microsoft implementation. 307So we provide a way to override it with your own AML code. 308.Pp 309In order to load your AML code, 310you must edit 311.Pa /boot/loader.conf 312and 313include the following lines. 314.Bd -literal -offset indent 315acpi_dsdt_load="YES" 316acpi_dsdt_name="/boot/acpi_dsdt.aml" #You may change the name. 317.Ed 318.Pp 319In order to prepare your AML code, you will need the 320.Xr acpidump 8 321and 322.Xr iasl 1 323utilities and some ACPI knowledge. 324.Sh TUNABLES 325.Bl -tag -width indent 326.It Va acpi_dsdt_load 327Enables loading of a custom ACPI DSDT. 328.It Va acpi_dsdt_name 329Name of the DSDT table to load, if loading is enabled. 330.It Va debug.acpi.disabled 331Selectively disables portions of ACPI for debugging purposes. 332.It Va hint.acpi.0.disabled 333Disables all of ACPI. 334.It Va hw.acpi.ec.poll_timeout 335Delay in milliseconds to wait for the EC to respond. 336Try increasing this number if you get the error 337.Er AE_NO_HARDWARE_RESPONSE . 338.It Va hw.acpi.reset_video 339Enables calling the VESA reset BIOS vector on the resume path. 340Some graphic chips have problems such as LCD white-out after resume. 341Try setting this to 0 if this causes problems for you. 342.It Va hw.acpi.osname 343Some systems' ASL may have problems because they look for names 344of Microsoft operating systems. 345This tunable overrides the value of the 346.Qq Li \e_OS 347object from its default of 348.Qq Li FreeBSD . 349.It Va hw.acpi.pci.link.%d.%d.%d.irq 350Override the interrupt to use. 351.It Va hw.acpi.verbose 352Turn on verbose debugging information about what ACPI is doing. 353.El 354.Sh SYSCTLS 355.Bl -tag -width indent 356.It Va hw.acpi.cpu.throttle_max 357Maximum value for CPU throttling, equal to 100% of the clock rate. 358.It Va hw.acpi.cpu.throttle_state 359Get or set the current throttling state, from 1 to 360.Va hw.acpi.cpu.throttle_max . 361This scales back the CPU clock rate and the corresponding power consumption. 362.It Va hw.acpi.cpu.cx_history 363Debugging information listing all sleep states and the number of 364long and short sleeps for each one. 365The counters are reset when 366.Va hw.acpi.cpu.cx_lowest 367is modified. 368.It Va hw.acpi.cpu.cx_lowest 369Lowest Cx state to use for idling the CPU. 370A scheduling algorithm will select states between C1 and this setting 371as system load dictates. 372To enable ACPI CPU idling control, 373.Va machdep.cpu_idle_hlt 374must be set to 1. 375.It Va hw.acpi.cpu.cx_supported 376List of supported CPU idle states and their transition latency 377in microseconds. 378Each state has a type (e.g., C2.) 379C1 is equivalent to the ia32 HLT instruction, C2 provides a deeper 380sleep with the same semantics, and C3 provides the deepest sleep 381but additionally requires bus mastering to be disabled. 382States greater than C3 provide even more power savings with the same 383semantics as the C3 state. 384Deeper sleeps provide more power savings but increased transition 385latency when an interrupt occurs. 386.El 387.Sh COMPATIBILITY 388ACPI is only found and supported on i386/ia32, ia64, and amd64. 389.Sh SEE ALSO 390.Xr kenv 1 , 391.Xr acpi_thermal 4 , 392.Xr device.hints 5 , 393.Xr loader.conf 5 , 394.Xr acpiconf 8 , 395.Xr acpidump 8 , 396.Xr config 8 , 397.Xr iasl 8 398.Rs 399.%A "Compaq Computer Corporation" 400.%A "Intel Corporation" 401.%A "Microsoft Corporation" 402.%A "Phoenix Technologies Ltd." 403.%A "Toshiba Corporation" 404.%D August 25, 2003 405.%T "Advanced Configuration and Power Interface Specification" 406.%O http://acpi.info/spec.htm 407.Re 408.Sh AUTHORS 409.An -nosplit 410The ACPI CA subsystem is developed and maintained by 411Intel Architecture Labs. 412.Pp 413The following people made notable contributions to the ACPI subsystem 414in 415.Fx : 416.An Michael Smith , 417.An Takanori Watanabe Aq takawata@jp.FreeBSD.org , 418.An Mitsuru IWASAKI Aq iwasaki@jp.FreeBSD.org , 419.An Munehiro Matsuda , 420.An Nate Lawson , 421the ACPI-jp mailing list at 422.Aq acpi-jp@jp.FreeBSD.org , 423and many other contributors. 424.Pp 425This manual page was written by 426.An Michael Smith Aq msmith@FreeBSD.org . 427.Sh BUGS 428If the 429.Nm 430driver is loaded as a module when it is already linked as part of the 431kernel, odd things may happen. 432