xref: /freebsd/share/man/man9/bios.9 (revision 6780ab54325a71e7e70112b11657973edde8655e)
1.\" $FreeBSD$
2.\"
3.\" Copyright (c) 1997 Michael Smith
4.\" All rights reserved.
5.\"
6.\" Redistribution and use in source and binary forms, with or without
7.\" modification, are permitted provided that the following conditions
8.\" are met:
9.\" 1. Redistributions of source code must retain the above copyright
10.\"    notice, this list of conditions and the following disclaimer.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice, this list of conditions and the following disclaimer in the
13.\"    documentation and/or other materials provided with the distribution.
14.\"
15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25.\" SUCH DAMAGE.
26.\"
27.Dd August 1, 1997
28.Dt BIOS 9
29.Os
30.Sh NAME
31.Nm bios_sigsearch ,
32.Nm bios32_SDlookup ,
33.Nm bios32
34.Nd interact with PC BIOS
35.Sh SYNOPSIS
36.In sys/param.h
37.In vm/vm.h
38.In vm/pmap.h
39.In machine/param.h
40.In machine/pmap.h
41.In machine/pc/bios.h
42.Ft u_int32_t
43.Fn bios_sigsearch "u_int32_t start" "u_char *sig" "int siglen" "int paralen" "int sigofs"
44.Ft int
45.Fn bios32_SDlookup "struct bios32_SDentry *ent"
46.Ft int
47.Fn bios32 "struct bios_regs *br" "u_int offset" "u_short segment"
48.Fn BIOS_PADDRTOVADDR "addr"
49.Fn BIOS_VADDRTOPADDR "addr"
50.Vt extern struct bios32_SDentry PCIbios ;
51.Vt extern struct SMBIOS_table SMBIOStable ;
52.Vt extern struct DMI_table DMItable ;
53.Sh DESCRIPTION
54These functions provide a general-purpose interface for dealing with
55the BIOS functions and data encountered on x86 PC-architecture systems.
56.Bl -tag -width 20n
57.It Fn bios_sigsearch
58Searches the BIOS address space for a service signature, usually an
59uppercase ASCII sequence surrounded by underscores.  The search begins
60at
61.Fa start ,
62or at the beginning of the BIOS if
63.Fa start
64is zero.
65.Fa siglen
66bytes of the BIOS image and
67.Fa sig
68are compared at
69.Fa sigofs
70bytes offset from the current location.  If no match is found, the
71current location is incremented by
72.Fa paralen
73bytes and the search repeated.  If the signature is found, its effective
74physical address is returned.  If no signature is found, zero is returned.
75.It Fn BIOS_VADDRTOPADDR
76Returns the effective physical address which corresponds to the kernel
77virtual address
78.Fa addr .
79.It Fn BIOS_VADDRTOPADDR
80Returns the kernel virtual address which corresponds to the effective
81physical address
82.Fa addr .
83.It SMBIOStable
84If not NULL, points to a
85.Ft struct SMBIOS_table
86structure containing information read from the System Management BIOS table
87during system startup.
88.It DMItable
89If not NULL, points to a
90.Ft struct DMI_table
91structure containing information read from the Desktop Management Interface
92parameter table during system startup.
93.El
94.Sh BIOS32
95At system startup, the BIOS is scanned for the BIOS32 Service Directory
96(part of the PCI specification), and the existence of the directory is
97recorded.  This can then be used to locate other services.
98.Bl -tag -width 20n
99.It Fn bios32_SDlookup
100Attempts to locate the BIOS32 service matching the 4-byte identifier
101passed in the
102.Fa ident
103field of the
104.Fa ent
105argument.
106.It Fn bios32
107Calls a bios32 function.  This presumes that the function is capable of
108working within the kernel segment (normally the case).  The virtual address
109of the entrypoint is supplied in
110.Fa entry
111and the register arguments to the function are supplied in
112.Fa args .
113.It PCIbios
114If not NULL, points to a
115.Ft struct bios32_SDentry
116structure describing the PCI BIOS entrypoint which was found during system
117startup.
118.El
119