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.Dd October 5, 2011
.Dt ACPI 4
.Os
.Sh NAME
.Nm acpi
.Nd Advanced Configuration and Power Interface
.Sh SYNOPSIS
.Cd acpi0	at mainbus0
.Pp
.Cd options	ACPI_DEBUG
.Cd options	ACPIVERBOSE
.Cd options	ACPI_ACTIVATE_DEV
.Cd options	ACPI_DSDT_OVERRIDE
.Cd options	ACPI_DSDT_FILE=""
.Cd options	ACPI_BLACKLIST_YEAR=2000
.Sh DESCRIPTION
.Nx
provides machine-independent bus support for
Advanced Configuration and Power Interface
.Pq Tn ACPI
devices and includes several
.Tn ACPI
device drivers.
.Pp
The
.Nx
implementation of
.Tn ACPI
integrates Intel's ACPI Component Architecture
.Pq Tn ACPI-CA
for the OS-independent part.
The
.Tn ACPI-CA
provides OS-neutral
.Tn ACPI
functionalities such as
.Tn ACPI
.Tn BIOS
table support,
an
.Tn ACPI
event framework and an ACPI Machine Language
.Pq Tn AML
interpreter.
.Pp
Options:
.Bl -tag -width ACPI_DSDT_FILE__filename_XX -offset 3n
.It Dv ACPI_DEBUG
Enable various debug facilities.
.It Dv ACPIVERBOSE
Enable verbose debug messages.
.It Dv ACPI_ACTIVATE_DEV
Determine if the
.Tn ACPI
driver should attempt to activate inactive devices.
The default is off.
.It Dv ACPI_DSDT_OVERRIDE
Force a given Differentiated System Description Table
.Pq Tn DSDT
instead of the version supplied by the
.Tn BIOS .
Use
.Dv ACPI_DSDT_FILE
to specify a
.Tn DSDT .
.It Dv ACPI_DSDT_FILE="filename"
If
.Dv ACPI_DSDT_FILE
is not specified, default to
.Dq dsdt.hex
in the build directory.
.It Dv ACPI_BLACKLIST_YEAR=2000
Do not use ACPI with any BIOS made on or before the specified year.
.El
.Sh SYSCTL SUPPORT
Few
.Xr sysctl 8
variables are directly relevant for
.Tn ACPI .
.Bl -tag -width "123456" -offset indent
.It Ic hw.acpi.root
The address of the
.Tn ACPI
root pointer in system memory.
.It Ic hw.acpi.sleep.state
The system sleep state.
.It Ic hw.acpi.sleep.states
A list of system sleep states that the machine supports.
The possible values are:
.Pp
.Bl -tag -width XS1X -offset indent -compact
.It S0
fully running
.It S1
power on suspend (CPU and hard disks are off)
.It S2
similar to S3, usually not implemented
.It S3
suspend-to-RAM
.It S4
suspend-to-disk (not supported on
.Nx )
.It S5
power off
.El
.It Ic hw.acpi.sleep.beep
A boolean variable that controls whether the
.Tn PC
speaker beeps upon resume.
.It Ic hw.acpi.sleep.vbios
Defines the handling of the graphics card.
The supported values are:
.Bl -tag -width '2' -offset 2n
.It 0
No attempt to reset the
.Tn VGA
controller will be made.
.It 1
Call the
.Tn VGA
.Tn BIOS
when still in real mode.
This can result in direct reboots.
In that case, use
.Sq 2
or
.Ic vbetool post
from the
.Pa pkgsrc/sysutils/vbetool
package.
.It 2
Call the
.Tn VGA
.Tn BIOS
using the in-kernel x86 emulator.
.El
.Pp
If the system has problems in resuming from the
.Tn S3
state, experimenting with different values may provide a solution.
.It Ic hw.acpi.stat.gpe
The number of dispatched General Purpose Events
.Pq Tn GPEs .
.It Ic hw.acpi.stat.sci
The number of System Control Interrupts
.Pq Tn SCIs .
See
.Xr acpiec 4
for a brief description of both
.Tn GPEs
and
.Tn SCIs .
.It Ic hw.acpi.stat.fixed
The number of
.Dq fixed events .
.It Ic hw.acpi.stat.method
The number of
.Tn ACPI
methods executed by the interpreter.
.It Ic hw.acpi.power
This read-only node describes the
.Tn ACPI
power state of devices.
The values range from
.Tn D0
.Pq Dq on
to
.Tn D3
.Pq Dq off .
.It Ic hw.acpi.wake
This node represents devices that can wake the system from the
.Tn S3
or
.Tn S4
sleep state.
By default,
.Xr acpibut 4 ,
.Xr acpilid 4 ,
and
.Xr pckbd 4
are allowed to wake the system, provided that the devices are present and
the firmware supports wake-up capabilities for the devices.
.El
.Sh SUPPORTED DEVICES
.Nx
.Tn ACPI
supports several machine-dependent and machine-independent devices,
some specific to
.Tn ACPI
and some configured via it.
.Ss Machine-independent devices
.Bl -tag -width "thinkpad(4) " -offset indent -compact
.It Xr acpiacad 4
.Tn ACPI
AC adapters.
.It Xr acpibat 4
.Tn ACPI
batteries.
.It Xr acpibut 4
.Tn ACPI
power and sleep buttons.
.It Xr acpicpu 4
.Tn ACPI
processors.
.It Xr acpidalb 4
.Tn ACPI
direction application launch buttons.
.It Xr acpiec 4
.Tn ACPI
embedded controllers.
.It Xr acpiecdt 4
.Tn ACPI
Embedded Controller Boot Resource Table
.Pq Tn ECDT .
.It Xr acpifan 4
.Tn ACPI
fans.
.It Xr acpilid 4
.Tn ACPI
lid switches.
.It Xr acpipmtr 4
.Tn ACPI
power meters.
.It Xr acpismbus 4
.Tn ACPI
SMBus via control method interface
.Pq Tn CMI .
.It Xr acpitz 4
.Tn ACPI
thermal zones.
.It Xr acpivga 4
.Tn ACPI
display adapter and output devices.
.It Xr acpiwmi 4
.Tn ACPI
support for Windows Management Instrumentation.
.It Xr acpiwdrt 4
.Tn ACPI
watchdogs.
.It Xr aibs 4
ASUSTeK voltage, temperature and fan sensors.
.It asus
ASUS laptop hotkeys.
.It Xr attimer 4
AT Timer.
.It Xr com 4
NS8250-, NS16450-, and NS16550-based serial ports.
.It Xr fdc 4
Floppy disk controllers.
.It Xr fujbp 4
Fujitsu brightness and pointer.
.It Xr fujhk 4
Fujitsu hotkeys.
.It Xr hpacel 4
HP 3D DriveGuard accelerometer.
.It Xr hpet 4
High Precision Event Timer
.Pq Tn HPET .
.It Xr hpqlb 4
HP Quick Launch Buttons.
.It Xr joy 4
Joystick/Game port interface.
.It Xr lpt 4
Standard ISA parallel port interface.
.It Xr mpu 4
Roland MPU-401 (compatible) MIDI UART.
.It Xr pcppi 4
AT-style speaker sound.
.It Xr thinkpad 4
IBM/Lenovo ThinkPad laptop device driver.
.It Xr ug 4
Abit uGuru Hardware monitor.
.It Xr vald 4
Toshiba Libretto device.
.It Xr wb 4
Winbond W83L518D Integrated Media Reader.
.It Xr wss 4
Windows Sound System-compatible sound cards
.It Xr ym 4
Yamaha OPL3-SA2 and OPL3-SA3 audio device driver.
.El
.Ss i386-dependent devices
.Bl -tag -width "thinkpad(4) " -offset indent -compact
.It Xr npx 4
i386 numeric processing extension coprocessor.
.It Xr pckbc 4
PC keyboard controllers.
.It Xr sony 4
Sony Miscellaneous Controller
.It Xr spic 4
Sony programmable I/O controller.
.El
.Sh DEBUGGING
Although the situation has become better over the years,
.Tn ACPI
is typically prone to various errors,
ranging from blatant flaws in the firmware to bugs in the implementation.
Before anything else, it is a good practice to upgrade the
.Tn BIOS
to the latest version available from the vendor.
.Pp
To ease the task of diagnosing and fixing different problems, the
.Tn ACPICA
reference implementation provides a rich
facility of different debugging methods.
In
.Nx
these are generally only available if the kernel has been compiled with the
.Tn ACPI_DEBUG
option.
.Ss Verbose messages
The
.Tn ACPIVERBOSE
compile time option enables some verbose
debug messages printed during the system startup.
In a
.Tn MODULAR
(see
.Xr options 4 )
system, the information can be printed also at runtime,
regardless of the presence of
.Tn ACPIVERBOSE .
To print the messages,
.Xr modload 8
the
.Ic acpiverbose
module using the option
.Ar -b dump=true .
.Ss Custom DSDT
.Tn ACPI
interprets bytecode known as
.Tn ACPI
Machine Language
.Pq Tn AML ,
provided by the
.Tn BIOS
as a memory image during the system bootstrap.
Most of the
.Tn AML
relevant to
.Nm
is implemented in the so-called
Differentiated System Descriptor Table
.Pq Tn DSDT .
.Nx
provides support for overriding the default
.Tn DSDT
supplied by the
.Tn BIOS .
.Pp
The following steps can be used to override the
.Tn DSDT :
.Bl -enum -offset indent
.It
Dump the raw
.Tn DSDT
with
.Xr acpidump 8 .
.It
Disassemble the table with
.Xr iasl 8 .
.It
Modify the disassembled table.
.It
Compile the table with
.Xr iasl 8
using the option
.Ar \-tc .
.It
Either copy the
.Pq Pa *.hex
file to
.Bd -literal -offset indent
src/sys/dev/acpi/acpica/Osd/custom_dsdt.hex
.Ed
.Pp
or use the option
.Bd -literal -offset indent
ACPI_DSDT_FILE="/some/directory/custom_dsdt.hex"
.Ed
.Pp
in the kernel configuration file.
.It
Define
.Tn ACPI_DSDT_OVERRIDE
in the kernel configuration file and rebuild.
.El
.Ss Debugger
The
.Tn ACPICA
interpreter provides its own debugger for low-level debugging.
It can be used to display internal data structures and namespace objects,
and to debug the execution of control methods.
Single step and breakpoint functionality are available.
In
.Nx
this is integrated to the in-kernel
.Xr ddb 4 .
In order to enter the
.Tn ACPICA
debugger from
.Xr ddb 4 ,
use the command
.Ic call
with the argument
.Ic acpi_osd_debugger .
.Ss Debug Output
.Nx
provides three
.Xr sysctl 8
variables that control the debug output at runtime.
The
.Ic hw.acpi.debug.layer
variable limits the output to a specific
.Tn ACPI
layer and the
.Ic hw.acpi.debug.level
variable controls the debug level.
Both
.Xr sysctl 8
variables are string literals.
The third variable is
.Ic hw.acpi.debug.object .
This is a boolean that controls whether debug messages internal to the
.Tn AML
are enabled.
.Pp
For the first two variables, the possible values are:
.Bl -column -offset indent \
"ACPI_RESOURCE_COMPONENT     " "ACPI_RESOURCE_COMPONENT     "
.It Sy LAYER Ta Sy LEVEL
.It Li ACPI_DEBUG_NONE Ta ACPI_DEBUG_NONE
.It Ta
.It Li ACPI_UTILITIES Ta ACPI_LV_INIT
.It Li ACPI_HARDWARE Ta ACPI_LV_DEBUG_OBJECT
.It Li ACPI_EVENTS Ta ACPI_LV_INFO
.It Li ACPI_TABLES Ta ACPI_LV_ALL_EXCEPTIONS *
.It Li ACPI_NAMESPACE Ta
.It Li ACPI_PARSER Ta ACPI_LV_INIT_NAMES
.It Li ACPI_DISPATCHER Ta ACPI_LV_PARSE
.It Li ACPI_EXECUTER Ta ACPI_LV_LOAD
.It Li ACPI_RESOURCES Ta ACPI_LV_DISPATCH
.It Li ACPI_CA_DEBUGGER Ta ACPI_LV_EXEC
.It Li ACPI_OS_SERVICES Ta ACPI_LV_NAMES
.It Li ACPI_CA_DISASSEMBLER Ta ACPI_LV_OPREGION
.It Li ACPI_COMPILER Ta ACPI_LV_BFIELD
.It Li ACPI_TOOLS Ta ACPI_LV_TABLES
.It Li ACPI_EXAMPLE Ta ACPI_LV_VALUES
.It Li ACPI_DRIVER Ta ACPI_LV_OBJECTS
.It Li ACPI_ALL_COMPONENTS * Ta ACPI_LV_RESOURCES
.It Ta ACPI_LV_USER_REQUESTS
.It Li ACPI_BUS_COMPONENT Ta ACPI_LV_PACKAGE
.It Li ACPI_ACAD_COMPONENT Ta ACPI_LV_VERBOSITY1 *
.It Li ACPI_BAT_COMPONENT Ta
.It Li ACPI_BUTTON_COMPONENT Ta ACPI_LV_ALLOCATIONS
.It Li APCI_EC_COMPONENT Ta ACPI_LV_FUNCTIONS
.It Li ACPI_LID_COMPONENT Ta ACPI_LV_OPTIMIZATIONS
.It Li ACPI_RESOURCE_COMPONENT Ta ACPI_LV_VERBOSITY2 *
.It Li ACPI_TZ_COMPONENT Ta
.It Li ACPI_DISPLAY_COMPONENT Ta
.It Li ACPI_ALL_DRIVERS * Ta ACPI_LV_MUTEX
.It Ta ACPI_LV_THREADS
.It Ta ACPI_LV_IO
.It Ta ACPI_LV_AML_INTERRUPTS
.It Li "* This is a compound" Ta ACPI_LV_VERBOSITY3 *
.It Li "  constant, including" Ta
.It Li "  all previous elements." Ta ACPI_LV_AML_DISASSEMBLE
.It Ta ACPI_LV_VERBOSE_INFO
.It Ta ACPI_LV_FULL_TABLES
.It Ta ACPI_LV_EVENTS
.It Ta ACPI_LV_VERBOSE *
.El
.Pp
In addition, there is
.Dv ACPI_DEBUG_DEFAULT
that is used by
.Tn ACPICA
as the default debug level.
It includes
.Dv ACPI_LV_INIT
and
.Dv ACPI_LV_DEBUG_OBJECT .
.Pp
The debug layer can be divided into two groups:
the first one is specific to the
.Tn ACPICA
interpreter and the second one contains the internal
.Tn ACPI
components of
.Nx .
The constant
.Dv ACPI_ALL_DRIVERS
includes all
.Nx
specific parts.
.Pp
The
.Tn ACPICA
interpreter uses several debug levels internally,
but the
.Nx
specific parts are typically limited to
.Dv ACPI_LV_DEBUG_OBJECT
and
.Dv ACPI_LV_INFO .
The debug output can be stopped by setting
.Ic hw.acpi.debug.level
to
.Dv ACPI_DEBUG_NONE .
.Ss Example
As an example, a driver may have defined the component it belongs to and
the name of the module:
.Bd -literal -offset indent
#define _COMPONENT	ACPI_BUS_COMPONENT
ACPI_MODULE_NAME	("acpi_example")
.Ed
.Pp
The driver may also utilize the debug facility:
.Bd -literal -offset indent
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Failed to evaluate _STA\\n"));
.Ed
.Pp
With these options the debug message from the
.Dv ACPI_DEBUG_PRINT
macro is only visible when
.Ic hw.acpi.debug.layer
is either
.Dv ACPI_BUS_COMPONENT
or a compound constant including it, and
.Ic hw.acpi.debug.level
is
.Dv ACPI_LV_INFO
or some constant that includes it.
Finally, it can be noted that the
.Tn ACPI
implementation uses the prefix
.Dv ACPI_DB ,
whereas the debug level
.Xr sysctl 8
variable is always specified with the prefix
.Dv ACPI_LV .
.Pp
Another example can be mentioned for the use of
.Ic hw.acpi.debug.object .
The following could appear in an
.Tn ASL
code:
.Bd -literal -offset indent
Method(_Q19, 0, NotSerialized)
{
	Store("_Q19 invoked", Debug)
	Notify(ACAD, 0x80)
}
.Ed
.Pp
When
.Ic hw.acpi.debug.object
is set to 1, the message stored to the debug object
is printed every time the method is called by the interpreter.
.Sh SEE ALSO
.Xr ioapic 4 ,
.Xr acpidump 8 ,
.Xr amldb 8 ,
.Xr iasl 8
.Rs
.%A Hewlett-Packard Corporation
.%A Intel Corporation
.%A Microsoft Corporation
.%A Phoenix Technologies Ltd.
.%A Toshiba Corporation
.%T Advanced Configuration and Power Interface Specification
.%N Revision 4.0
.%D June 16, 2009
.%U http://www.acpi.info/spec.htm
.Re
.Rs
.%A Intel Corporation
.%T ACPI Component Architecture,
.%T Programmer Reference,
.%T OS-Independent Subsystem, Debugger, and Utilities
.%N Revision 1.27
.%D January 20, 2010
.%U http://www.acpica.org/download/acpica-reference.pdf
.Re
.Rs
.%A Len Brown
.%T ACPI in Linux - Myths vs. Reality
.%D June 27-30, 2007
.%O Proceedings of the Linux Symposium
.%P 65-74
.%U http://www.linuxsymposium.org/archives/OLS/Reprints-2007/brown_1-Reprint.pdf
.Re
.Rs
.%A Joerg Sonnenberger
.%A Jared D. McNeill
.%T Sleeping Beauty - NetBSD on Modern Laptops
.%D February 3, 2008
.%O Proceedings of AsiaBSDCon 2008
.%P 127-134
.%U http://2008.asiabsdcon.org/papers/P9A-paper.pdf
.Re
.Rs
.%A Takanori Watanabe
.%T ACPI Implementation on FreeBSD
.%I USENIX Association
.%B Proceedings of the FREENIX Track: 2002 USENIX Annual Technical Conference
.%P 121-131
.%D June 10-15, 2002
.%U http://www.usenix.org/event/usenix02/tech/freenix/full_papers/watanabe/watanabe.pdf
.Re
.Sh HISTORY
The
.Nm
driver
appeared in
.Nx 1.6 .
.Sh AUTHORS
.An -nosplit
Authors of the
.Nm
subsystem include
.An Charles M. Hannum ,
.An Frank van der Linden ,
.An Jared D. McNeill ,
.An Jason R. Thorpe ,
.An Joerg Sonnenberger ,
and
.An Jukka Ruohonen ,
among others.
.Sh BUGS
Most of the
.Tn ACPI
power management functionalities are not implemented.