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.\" ACPI (ACPI Package)
.\"
.\" Copyright (c) 1999 Doug Rabson <dfr@FreeBSD.org>
.\" Copyright (c) 2000 Mitsuru IWASAKI <iwasaki@FreeBSD.org>
.\" Copyright (c) 2000 Yasuo YOKOYAMA <yokoyama@jp.FreeBSD.org>
.\" Copyright (c) 2000 Hiroki Sato <hrs@FreeBSD.org>
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
.Dd June 29, 2020
.Dt ACPIDUMP 8
.Os
.Sh NAME
.Nm acpidump
.Nd dump ACPI tables and ASL
.Sh SYNOPSIS
.Nm
.Op Fl d
.Op Fl t
.Op Fl h
.Op Fl v
.Op Fl f Ar dsdt_input
.Op Fl o Ar dsdt_output
.Sh DESCRIPTION
The
.Nm
utility analyzes ACPI tables in physical memory and can dump them to a file.
In addition,
.Nm
can call
.Xr iasl 8
to disassemble AML
(ACPI Machine Language)
found in these tables and dump them as ASL
(ACPI Source Language)
to stdout.
.Pp
ACPI tables have an essential data block (the DSDT,
Differentiated System Description Table)
that includes information used on the kernel side such as
detailed information about PnP hardware, procedures for controlling
power management support, and so on.
The
.Nm
utility can extract the DSDT data block from physical memory and store it into
an output file and optionally also disassemble it.
If any Secondary System Description Table
(SSDT)
entries exist, they will also be included in the output file and disassembly.
.Pp
When
.Nm
is invoked without the
.Fl f
option, it will read ACPI tables from physical memory via
.Pa /dev/mem .
First it searches for the RSDP
(Root System Description Pointer),
which has the signature
.Qq RSD PTR\ \& ,
and then gets the RSDT
(Root System Description Table),
which includes a list of pointers to physical memory addresses
for other tables.
The RSDT itself and all other tables linked from RSDT are generically
called SDTs
(System Description Tables)
and their header has a common format which consists of items
such as Signature, Length, Revision, Checksum, OEMID, OEM Table ID,
OEM Revision, Creator ID and Creator Revision.
When invoked with the
.Fl t
flag, the
.Nm
utility dumps contents of the following tables:
.Pp
.Bl -tag -offset indent -width 12345 -compact
.It BERT
.It DMAR
.It DSDT
.It ECDT
.It EINJ
.It ERST
.It FACS
.It FADT
.It HEST
.It HPET
.It LPIT
.It MADT
.It MCFG
.It NFIT
.It RSD PTR
.It RSDT
.It SLIT
.It SRAT
.It TCPA
.It TPM2
.It WDDT
.El
.Pp
The RSDT contains a pointer to the physical memory address of the FACP
(Fixed ACPI Description Table).
The FACP defines static system information about power management support
(ACPI Hardware Register Implementation)
such as interrupt mode (INT_MODEL),
SCI interrupt number, SMI command port (SMI_CMD)
and the location of ACPI registers.
The FACP also has a pointer to a physical memory address for the DSDT.
While the other tables are fixed format,
the DSDT consists of free-formatted AML data.
.Sh OPTIONS
The following options are supported by
.Nm :
.Bl -tag -width indent
.It Fl d
Disassemble the DSDT into ASL using
.Xr iasl 8
and print the results to stdout.
.It Fl t
Dump the contents of the various fixed tables listed above.
.It Fl h
Displays usage and exit.
.It Fl v
Enable verbose messages.
.It Fl f Ar dsdt_input
Load the DSDT from the specified file instead of physical memory.
Since only the DSDT is stored in the file, the
.Fl t
flag may not be used with this option.
.It Fl o Ar dsdt_output
Store the DSDT data block from physical memory into the specified file.
.El
.Sh FILES
.Bl -tag -width /dev/mem
.It Pa /dev/mem
.El
.Sh EXAMPLES
If a developer requests a copy of your ASL, please use the following
command to dump all tables and compress the result.
.Bd -literal -offset indent
# acpidump -dt | gzip -c9 > my_computer.asl.gz
.Ed
.Pp
This example dumps the DSDT from physical memory to foo.dsdt.
It also prints the contents of various system tables and disassembles
the AML contained in the DSDT to stdout, redirecting the output
to foo.asl.
.Bd -literal -offset indent
# acpidump -t -d -o foo.dsdt > foo.asl
.Ed
.Pp
This example reads a DSDT file and disassembles it to stdout.
Verbose messages are enabled.
.Bd -literal -offset indent
# acpidump -v -d -f foo.dsdt
.Ed
.Sh SEE ALSO
.Xr acpi 4 ,
.Xr mem 4 ,
.Xr acpiconf 8 ,
.Xr acpidb 8 ,
.Xr iasl 8
.Sh HISTORY
The
.Nm
utility first appeared in
.Fx 5.0
and was rewritten to use
.Xr iasl 8
for
.Fx 5.2 .
.Sh AUTHORS
.An Doug Rabson Aq Mt dfr@FreeBSD.org
.An Mitsuru IWASAKI Aq Mt iwasaki@FreeBSD.org
.An Yasuo YOKOYAMA Aq Mt yokoyama@jp.FreeBSD.org
.An Nate Lawson Aq Mt njl@FreeBSD.org
.Pp
.An -nosplit
Some contributions made by
.An Chitoshi Ohsawa Aq Mt ohsawa@catv1.ccn-net.ne.jp ,
.An Takayasu IWANASHI Aq Mt takayasu@wendy.a.perfect-liberty.or.jp ,
.An Yoshihiko SARUMARU Aq Mt mistral@imasy.or.jp ,
.An Hiroki Sato Aq Mt hrs@FreeBSD.org ,
.An Michael Lucas Aq Mt mwlucas@blackhelicopters.org
and
.An Michael Smith Aq Mt msmith@FreeBSD.org .
.Sh BUGS
The current implementation does not dump the BOOT structure or
other miscellaneous tables.