1.\" $OpenBSD: bios.4,v 1.3 2001/08/03 15:21:16 mpech Exp $ 2.\" 3.\" Copyright (c) 2001 Michael Shalayeff 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.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by Michael Shalayeff. 17.\" 4. The name of the author may not be used to endorse or promote products 18.\" derived from this software without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 22.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 23.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 24.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 25.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF MIND, 26.\" USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 29.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30.\" 31.Dd February 28, 2001 32.Dt BIOS 4 33.Os 34.Sh NAME 35.Nm bios 36.Nd a driver for PC Firmware, aka BIOS 37.Sh SYNOPSIS 38.Cd "bios0 at mainbus0 flags 0x0000" 39.Cd "apm0 at bios0 flags 0x0000" 40.Cd "pcibios0 at bios0 flags 0x0000" 41.Sh INTRODUCTION 42.Ox 43provides support for PC firmware, aka BIOS and some of it's functions, 44currently: APM subsystem, BIOS 32 extensions, PCI BIOS subsystem. 45.Pp 46The 47.Nm 48driver also identifies BIOS type (such as "AT/286+", which is 49almost always used in modern machines) and BIOS image date stamp, 50which is, presumably, the day bios image was compiled by vendor 51and could be used as a crude BIOS version identification. 52The 53.Nm 54driver also scans the ISA memory hole at 640K-1M for optional 55ROM images and reserves the space from being used by various 56isa devices, for example 57.Xr pcic 4 . 58.Pp 59Flags is a bit mask each bit of which specifies which functions 60of the driver to disable. 61.Bl -tag -width 0x0001 62.It 0x0001 63BIOS 32 attachment. 64.Pp 65Do not probe and attach to BIOS 32 extensions, which is one of 66the interfaces to the PCI BIOS configuration tables. 67.It 0x0002 68PCI BIOS attachment. 69.Pp 70Do not probe and attach the 71.Xr pcibios 4 72device, which performs certain PCI configuration tasks. 73.It 0x0004 74Do not perform the scan for ROM images in the ISA memory hole 75(0xc0000 - 0xf0000 physical addresses). 76.El 77.Sh SEE ALSO 78.Xr apm 4 , 79.Xr pcibios 4 80.Sh HISTORY 81The 82.Nm 83driver 84appeared in 85.Ox 2.2 . 86.Sh BUGS 87On some machines optional ROM images do not pass checksum check, 88but it's considered better to reserve space for those anyway, 89choosing lesser evil from many. 90