1/*        $NetBSD: biosgetrtc.S,v 1.7 2011/06/16 13:27:59 joerg Exp $ */
2
3/*
4 * Copyright (c) 1996
5 *        Matthias Drochner.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 */
28
29#include <machine/asm.h>
30
31ENTRY(biosgetrtc)
32          pusha
33          pushl     %eax
34
35          xorl      %ebx, %ebx
36
37          call      _C_LABEL(prot_to_real)        # enter real mode
38          .code16
39
40          movb      $2, %ah
41          int       $0x1a
42          jnc       ok
43          movl      $-1, %ebx
44
45ok:
46          calll     _C_LABEL(real_to_prot) # back to protected mode
47          .code32
48
49          popl      %eax
50          movb      %ch, (%eax)
51          movb      %cl, 1(%eax)
52          movb      %dh, 2(%eax)
53          movb      $0,  3(%eax)
54
55          movl      %ebx, 28(%esp)
56
57          popa
58          ret
59