1/* $NetBSD: biosgetrtc.S,v 1.2 1997/06/13 13:42:27 drochner 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 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed for the NetBSD Project 18 * by Matthias Drochner. 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 * 33 */ 34 35#include <machine/asm.h> 36 37#define addr32 .byte 0x67 38#define data32 .byte 0x66 39 40ENTRY(biosgetrtc) 41 pushl %ebp 42 movl %esp, %ebp 43 pushl %ebx 44 pushl %ecx 45 pushl %edx 46 push %esi 47 push %edi 48 49 xorl %ebx, %ebx 50 51 call _C_LABEL(prot_to_real) # enter real mode 52 53 movb $2, %ah 54 int $0x1a 55 jnc ok 56 data32 57 movl $-1, %ebx 58 59ok: 60 data32 61 call _C_LABEL(real_to_prot) # back to protected mode 62 63 movl 8(%ebp), %eax 64 movl $0, (%eax) 65 movb %ch, (%eax) 66 movb %cl, 1(%eax) 67 movb %dh, 2(%eax) 68 69 movl %ebx, %eax 70 71 pop %edi 72 pop %esi 73 popl %edx 74 popl %ecx 75 popl %ebx 76 popl %ebp 77 ret 78