1/* $NetBSD: biosdelay.S,v 1.2.2.1 2005/11/10 13:56:54 skrll Exp $ */ 2 3/* 4 * Copyright (c) 1996, 1997 5 * Perry E. Metzger. 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 acknowledgements: 17 * This product includes software developed for the NetBSD Project 18 * by Perry E. Metzger. 19 * 4. The names of the authors 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 .text 38 39/* 40 * BIOS call "INT 15H Function 86H" to sleep for a set number of microseconds 41 * Call with %ah = 0x86 42 * %cx = time interval (high) 43 * %dx = time interval (low) 44 * Return: 45 * If error 46 * CF = set 47 * else 48 * CF = clear 49 */ 50ENTRY(delay) 51 pushl %ebp 52 pushl %ebx 53 pushl %esi 54 pushl %edi 55 56 movw 20(%esp), %dx 57 movw 22(%esp), %cx 58 59 call _C_LABEL(prot_to_real) 60 .code16 61 62 movb $0x86, %ah 63 int $0x15 64 setnc %ah 65 66 movb %ah, %bl # real_to_prot uses %eax 67 68 calll _C_LABEL(real_to_prot) 69 .code32 70 71 xorl %eax, %eax 72 movb %bl, %al 73 74 popl %edi 75 popl %esi 76 popl %ebx 77 popl %ebp 78 ret 79