/* $NetBSD: biosmca.S,v 1.4 2003/02/01 14:48:18 dsl Exp $ */
/*
* Ported to boot 386BSD by Julian Elischer (
[email protected]) Sept 1992
*
* Mach Operating System
* Copyright (c) 1992, 1991 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or
[email protected]
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
Copyright 1988, 1989, 1990, 1991, 1992
by Intel Corporation, Santa Clara, California.
All Rights Reserved
Permission to use, copy, modify, and distribute this software and
its documentation for any purpose and without fee is hereby
granted, provided that the above copyright notice appears in all
copies and that both the copyright notice and this permission notice
appear in supporting documentation, and that the name of Intel
not be used in advertising or publicity pertaining to distribution
of the software without specific, written prior permission.
INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* extracted from netbsd:sys/arch/i386/stand/bios_disk.S */
#include <machine/asm.h>
.data
.globl _C_LABEL(biosmca_ps2model)
_C_LABEL(biosmca_ps2model): .long 0
.text
/*
# BIOS call "INT 0x15 Function 0xc0" to read extended sys config info on PS/2
# Return: no return value
#
# This function initializes biosmca_ps2model with model number as
# identified by BIOS, if the machine is a PS/2 box (i.e. has MCA bus
# instead of ISA).
*/
ENTRY(biosmca)
.code32
pushl %ebp
movl %esp, %ebp
pushl %ebx
push %ecx
push %edx
push %esi
push %edi
push %eax
call _C_LABEL(prot_to_real) # enter real mode
.code16
# zero %ecx
xorl %ecx, %ecx
xor %ax, %ax
movb $0xc0, %ah # subfunction
int $0x15
jc back
# check feature byte 1 if MCA bus present and replaces ISA
movb %es:5(%bx), %al
andb $0x02, %al # bit 1 set means MCA instead of ISA
# see also arch/i386/mca/mca_machdep.c
jnz back
# save model and submodel bytes to %cx
movb %es:2(%bx), %ch # model (1 byte)
movb %es:3(%bx), %cl # submodel (1 byte)
back:
calll _C_LABEL(real_to_prot) # back to protected mode
.code32
# save model
movl %ecx, _C_LABEL(biosmca_ps2model)
pop %eax
pop %edi
pop %esi
pop %edx
pop %ecx
popl %ebx
popl %ebp
ret
