biosmemx.S revision 1.9
1 /* $NetBSD: biosmemx.S,v 1.9 2008/10/14 14:18:11 ad Exp $ */ 2 3 /* 4 * Copyright (c) 1997, 1999 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 31 .text 32 33 /* int getextmem2(int buffer[2]) 34 return: 0=OK, -1=error 35 buffer[0]: extmem kBytes below 16M (max 15M/1024) 36 buffer[1]: extmem above 16M, in 64k units 37 */ 38 ENTRY(getextmem2) 39 pushl %ebp 40 movl %esp,%ebp 41 pushl %ebx 42 pushl %ecx 43 pushl %edx 44 push %esi 45 push %edi 46 47 call _C_LABEL(prot_to_real) 48 .code16 49 50 xorl %ebx, %ebx 51 movl $0xe801, %eax 52 int $0x15 53 pushf 54 55 movw %si, %ax 56 orw %si, %bx 57 jz 1f /* if zero use configured values */ 58 movw %cx, %ax /* k below 16M (max 0x3c00 = 15MB) */ 59 movw %dx, %bx /* 64k above 16M */ 60 1: 61 popf 62 setc %bl 63 64 calll _C_LABEL(real_to_prot) 65 .code32 66 67 movl 8(%ebp), %edi 68 xorl %eax, %eax 69 movw %cx, %ax 70 stosl 71 movw %dx, %ax 72 stosl 73 movb %bl, %al 74 cbw 75 76 pop %edi 77 pop %esi 78 popl %edx 79 popl %ecx 80 popl %ebx 81 popl %ebp 82 ret 83 84 /* int getmementry(int *iterator, buffer[5]) 85 return: 0=ok, else error 86 buffer[0]: start of memory chunk 87 buffer[2]: length (bytes) 88 buffer[4]: type 89 */ 90 ENTRY(getmementry) 91 pushl %ebp 92 movl %esp,%ebp 93 pushl %ebx 94 pushl %ecx 95 pushl %edx 96 push %esi 97 push %edi 98 99 movl 8(%ebp), %eax 100 movl 0(%eax), %ebx /* index */ 101 movl $20, %ecx /* Buffer size */ 102 movl $0x534d4150, %edx /* "SMAP" */ 103 movl 12(%ebp), %edi /* buffer address */ 104 105 call _C_LABEL(prot_to_real) 106 .code16 107 108 push %di 109 shrl $4, %edi 110 mov %ds, %ax 111 add %di, %ax 112 mov %ax, %es 113 pop %di 114 and $0xf, %di /* buffer addres now in ES:DI */ 115 116 movl $0xe820, %eax /* Some BIOS check EAX value */ 117 int $0x15 118 119 setc %cl 120 121 calll _C_LABEL(real_to_prot) 122 .code32 123 124 movl 8(%ebp), %eax 125 movl %ebx, 0(%eax) /* updated index */ 126 xorl %eax, %eax 127 movb %cl, %al 128 129 pop %edi 130 pop %esi 131 popl %edx 132 popl %ecx 133 popl %ebx 134 popl %ebp 135 ret 136 137 /* int biosA20(void) 138 return: 0=ok, else error 139 */ 140 ENTRY(biosA20) 141 pushl %ebp 142 movl %esp,%ebp 143 pushl %ebx 144 pushl %ecx 145 pushl %edx 146 push %esi 147 push %edi 148 149 call _C_LABEL(prot_to_real) 150 .code16 151 152 movl $0x2401, %eax 153 int $0x15 154 setc %cl 155 156 calll _C_LABEL(real_to_prot) 157 .code32 158 159 movzbl %cl, %eax 160 161 pop %edi 162 pop %esi 163 popl %edx 164 popl %ecx 165 popl %ebx 166 popl %ebp 167 ret 168
Indexes created Tue Sep 30 06:09:59 GMT 2025