biosvideomode.S revision 1.1
1 1.1 tsarna 2 1.1 tsarna /* 3 1.1 tsarna * Copyright (c) 1996 4 1.1 tsarna * Perry E. Metzger. All rights reserved. 5 1.1 tsarna * 6 1.1 tsarna * Redistribution and use in source and binary forms, with or without 7 1.1 tsarna * modification, are permitted provided that the following conditions 8 1.1 tsarna * are met: 9 1.1 tsarna * 1. Redistributions of source code must retain the above copyright 10 1.1 tsarna * notice, this list of conditions and the following disclaimer. 11 1.1 tsarna * 2. Redistributions in binary form must reproduce the above copyright 12 1.1 tsarna * notice, this list of conditions and the following disclaimer in the 13 1.1 tsarna * documentation and/or other materials provided with the distribution. 14 1.1 tsarna * 3. All advertising materials mentioning features or use of this software 15 1.1 tsarna * must display the following acknowledgements: 16 1.1 tsarna * This product includes software developed for the NetBSD Project 17 1.1 tsarna * by Perry E. Metzger. 18 1.1 tsarna * 4. The names of the authors may not be used to endorse or promote products 19 1.1 tsarna * derived from this software without specific prior written permission. 20 1.1 tsarna * 21 1.1 tsarna * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 1.1 tsarna * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 1.1 tsarna * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 1.1 tsarna * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 1.1 tsarna * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 1.1 tsarna * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 1.1 tsarna * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 1.1 tsarna * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 1.1 tsarna * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 1.1 tsarna * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 1.1 tsarna * 32 1.1 tsarna */ 33 1.1 tsarna 34 1.1 tsarna 35 1.1 tsarna #include <machine/asm.h> 36 1.1 tsarna 37 1.1 tsarna #define data32 .byte 0x66 38 1.1 tsarna 39 1.1 tsarna .text 40 1.1 tsarna 41 1.1 tsarna ENTRY(biosvideomode) 42 1.1 tsarna pushl %ebp 43 1.1 tsarna movl %esp,%ebp 44 1.1 tsarna pushl %ebx 45 1.1 tsarna push %esi 46 1.1 tsarna push %edi 47 1.1 tsarna 48 1.1 tsarna call _C_LABEL(prot_to_real) 49 1.1 tsarna 50 1.1 tsarna movb $0, %ah 51 1.1 tsarna movb $2, %al 52 1.1 tsarna int $0x10 53 1.1 tsarna # zero-extend 16-bit result to 32 bits. 54 1.1 tsarna data32 55 1.1 tsarna movl $0, %ebx 56 1.1 tsarna mov %eax,%ebx # !!! at run time, it is mov %ax,%bx 57 1.1 tsarna 58 1.1 tsarna data32 59 1.1 tsarna call _C_LABEL(real_to_prot) 60 1.1 tsarna 61 1.1 tsarna movl %ebx, %eax 62 1.1 tsarna 63 1.1 tsarna pop %edi 64 1.1 tsarna pop %esi 65 1.1 tsarna popl %ebx 66 1.1 tsarna popl %ebp 67 1.1 tsarna ret 68
Indexes created Mon Sep 29 03:10:08 GMT 2025