smapi(4)
NAME
- smapi - System Management Application Program Interface
- driver
DESCRIPTION
- Many IBM Thinkpad laptops utilize a special software inter
- face known as
SMAPI (System Management Application Program Interface).
- This interface
controls various aspects of the system including:
- +o System Interface (the BIOS can store system information
- such as the
- system identifier),
- +o System Configuration (where devices such as the display
- can be con
- figured),
- +o Power Management (software can interact with the SMAPI
- BIOS for Power
- Management control).
- Client software must locate a ``header image'' stored in the
- F000 segment
in the Thinkpad ROM (read-only memory), which resides at the
- 16-byte
boundary. This is considered the ``Entry Point'' for the
- service.
- The ``header image'' stores information like:
- +o signature,
- +o SMAPI version (major and minor),
- +o header image length,
- +o checksum information (which verifies the image),
- +o an Information Word (used to identify the BIOS service
- level),
- +o Real Mode Entry Point (where clients using the Real/V86
- mode for the
- far-call value),
- +o and finally a 16-bit/32-bit Protected Mode Entry Point:
- base code
- address which specifies the BIOS physical address. The
- client must
prepare a 64 kilobyte selector for this BIOS).
- To invoke the SMAPI BIOS, a far-call must be used on the en
- try point
specified in the header file. All other information should
- be stored in
the client data area. The client is required to prepare
- both an input
and output parameter in a data area of its own. This area
- can be
``informed'' by pushing those pointers into its stack before
- the farcalls.
- The SMAPI BIOS uses the stack and data areas with the selec
- tor during a
BIOS invocation, thus the caller must define the same privi
- lege area as
the BIOS.
- The parameter structure will be made up by using the input
- and output
fields prepared by the caller. The input field will specify
- the function
request to the BIOS. The BIOS will then drop a return value
- into the
output field. These fields are made up of three parts. The
- first holds
parameters, function numbers, and return codes. The next
- will contain an
offset in hexadecimal. Finally a length field which is com
- prised of
Byte, Word, or Double Word.
SEE ALSO
- IBM Thinkpad 560/560E Technical Reference, 06J0536
- S76H-7587-01.
- IBM Thinkpad 560Z Technical Reference, xxxxxxx xxxx-xxxx-xx.
- IBM Thinkpad 600 Technical Reference, xxxxxxx xxxx-xxxx-xx.
- IBM Thinkpad 760XD/760XL/765D/765L Technical Reference,
- 06J0537
S30H-2433-02.
- IBM Thinkpad 770 Technical Reference, 05L1739 S05L-1739-00.
AUTHORS
- The smapi driver was written by Matthew N. Dodd
- <mdodd@FreeBSD.org>.
This manual page was written by Tom Rhodes <trhodes@FreeB
- SD.org> and
Matthew N. Dodd <mdodd@FreeBSD.org>.
- BSD April 1, 2003