NetBSD/sys/arch/i386/stand/lib/biosgetrtc.S

77 lines
2.3 KiB
ArmAsm

/* $NetBSD: biosgetrtc.S,v 1.1.1.1 1997/03/14 02:40:32 perry Exp $ */
/*
* Copyright (c) 1996
* Matthias Drochner. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project
* by Matthias Drochner.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <machine/asm.h>
#define addr32 .byte 0x67
#define data32 .byte 0x66
ENTRY(biosgetrtc)
pushl %ebp
movl %esp, %ebp
pushl %ebx
pushl %ecx
pushl %edx
push %esi
push %edi
xorl %ebx, %ebx
call _C_LABEL(prot_to_real) # enter real mode
movb $2, %ah
int $0x1a
jnc ok
movl $-1, %ebx
ok:
data32
call _C_LABEL(real_to_prot) # back to protected mode
movl 8(%ebp), %eax
movl $0, (%eax)
movb %ch, (%eax)
movb %cl, 1(%eax)
movb %dh, 2(%eax)
movl %ebx, %eax
pop %edi
pop %esi
popl %edx
popl %ecx
popl %ebx
popl %ebp
ret