1/* $NetBSD: biosmca.S,v 1.4 2003/02/01 14:48:18 dsl Exp $ */ 2 3/* 4 * Ported to boot 386BSD by Julian Elischer (julian@tfs.com) Sept 1992 5 * 6 * Mach Operating System 7 * Copyright (c) 1992, 1991 Carnegie Mellon University 8 * All Rights Reserved. 9 * 10 * Permission to use, copy, modify and distribute this software and its 11 * documentation is hereby granted, provided that both the copyright 12 * notice and this permission notice appear in all copies of the 13 * software, derivative works or modified versions, and any portions 14 * thereof, and that both notices appear in supporting documentation. 15 * 16 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 17 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 18 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 19 * 20 * Carnegie Mellon requests users of this software to return to 21 * 22 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 23 * School of Computer Science 24 * Carnegie Mellon University 25 * Pittsburgh PA 15213-3890 26 * 27 * any improvements or extensions that they make and grant Carnegie Mellon 28 * the rights to redistribute these changes. 29 */ 30 31/* 32 Copyright 1988, 1989, 1990, 1991, 1992 33 by Intel Corporation, Santa Clara, California. 34 35 All Rights Reserved 36 37Permission to use, copy, modify, and distribute this software and 38its documentation for any purpose and without fee is hereby 39granted, provided that the above copyright notice appears in all 40copies and that both the copyright notice and this permission notice 41appear in supporting documentation, and that the name of Intel 42not be used in advertising or publicity pertaining to distribution 43of the software without specific, written prior permission. 44 45INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE 46INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, 47IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR 48CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 49LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT, 50NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 51WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 52*/ 53 54/* extracted from netbsd:sys/arch/i386/stand/bios_disk.S */ 55 56#include <machine/asm.h> 57 58 .data 59 .globl _C_LABEL(biosmca_ps2model) 60_C_LABEL(biosmca_ps2model): .long 0 61 62 .text 63/* 64# BIOS call "INT 0x15 Function 0xc0" to read extended sys config info on PS/2 65# Return: no return value 66# 67# This function initializes biosmca_ps2model with model number as 68# identified by BIOS, if the machine is a PS/2 box (i.e. has MCA bus 69# instead of ISA). 70*/ 71ENTRY(biosmca) 72 .code32 73 pushl %ebp 74 movl %esp, %ebp 75 pushl %ebx 76 push %ecx 77 push %edx 78 push %esi 79 push %edi 80 push %eax 81 82 call _C_LABEL(prot_to_real) # enter real mode 83 .code16 84 85 # zero %ecx 86 xorl %ecx, %ecx 87 88 xor %ax, %ax 89 movb $0xc0, %ah # subfunction 90 int $0x15 91 jc back 92 93 # check feature byte 1 if MCA bus present and replaces ISA 94 movb %es:5(%bx), %al 95 andb $0x02, %al # bit 1 set means MCA instead of ISA 96 # see also arch/i386/mca/mca_machdep.c 97 jnz back 98 99 # save model and submodel bytes to %cx 100 movb %es:2(%bx), %ch # model (1 byte) 101 movb %es:3(%bx), %cl # submodel (1 byte) 102 103back: 104 calll _C_LABEL(real_to_prot) # back to protected mode 105 .code32 106 107 # save model 108 movl %ecx, _C_LABEL(biosmca_ps2model) 109 110 pop %eax 111 pop %edi 112 pop %esi 113 pop %edx 114 pop %ecx 115 popl %ebx 116 popl %ebp 117 ret 118