ACPIDUMP(8)

NAME
acpidump - dump ACPI tables

SYNOPSIS
acpidump [-r]
acpidump [-r] [-o dsdt_file_for_output]
acpidump [-r] [-f dsdt_file_for_input]

DESCRIPTION
The acpidump utility analyzes ACPI tables in physical memory and dumps them to standard output. In addition, acpidump can disassemble AML (ACPI Machine Language) found in these tables and dump them as ASL (ACPI Source Language).

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 acpidump utility can extract the DSDT data block from physical memory and store it into a DSDT data file, and also can generate an output in ASL from a given DSDT data file.

When acpidump is invoked without the -f option, it will read ACPI tables from physical memory via a special file /dev/mem and dump them. First it searches for the RSDP (Root System Description Pointer), which has the signature "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. The acpidump utility dumps contents of these SDTs. For further information about formats of each table, see chapter 5: “ACPI Software Programming Model” from the ACPI specifications referenced below.

There is always a pointer to a physical memory address in RSDT for 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 location of ACPI registers. The FACP also has a pointer to a physical memory address for DSDT, which includes information used on the kernel side such as PnP, power management support and so on. While the other tables are described in fixed format, the DSDT consists of AML data which is compiled from sources written in free formated ASL, which is the description language for ACPI. When acpidump outputs DSDT, it disassembles the AML data and formats it as ASL.

OPTIONS
The following options are supported by acpidump:

-f dsdt_file_for_input
    Interprets AML data in DSDT from a file specified in dsdt_file_for_input and dumps them in ASL to standard output.

-h  Displays usage and exits.

-o dsdt_file_for_output
    Stores DSDT data block from physical memory into a file specified in dsdt_file_for_output in addition to behavior with no option.

-r  Additionally outputs commented ResourceTemplate() macros for Buffer objects that contain valid resource streams. These macros are defined in the ACPI 2.0 specification section 16.2.4.

FILES

/dev/mem

EXAMPLES
This is an example to get a dump of SDTs and a DSDT data file simultaneously on a machine that supports ACPI BIOS.

    # acpidump -o foo.dsdt  foo.asl

SEE ALSO
acpi(4), amldb(8)

Advanced Configuration and Power Interface Specification, Intel, Microsoft, Toshiba, Revision 1.0b, 2.0.

HISTORY
The acpidump utility appeared in FreeBSD 5.0.

AUTHORS
Doug Rabson <dfr@FreeBSD.org> Mitsuru IWASAKI <iwasaki@FreeBSD.org> Yasuo YOKOYAMA <yokoyama@jp.FreeBSD.org>

-nosplit Some contributions made by Chitoshi Ohsawa <ohsawa@catv1.ccn-net.ne.jp>, Takayasu IWANASHI <takayasu@wendy.a.perfect-liberty.or.jp>, Yoshihiko SARUMARU <mistral@imasy.or.jp>, Hiroki Sato <hrs@FreeBSD.org>, Michael Lucas <mwlucas@blackhelicopters.org> and Michael Smith <msmith@FreeBSD.org>.

BUGS
In the current implementation, acpidump doesn't dump any information of Firmware ACPI Control Structure (FACS) specified by a pointer in FACP.