biosmemx.S revision 1.10
1 /* $NetBSD: biosmemx.S,v 1.10 2016/12/04 08:21:08 maxv 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 /* 34 * int getextmem2(int buffer[2]) 35 * 36 * return: 0=OK, -1=error 37 * buffer[0]: extmem kBytes below 16M (max 15M/1024) 38 * buffer[1]: extmem above 16M, in 64k units 39 */ 40 ENTRY(getextmem2) 41 pushl %ebp 42 movl %esp,%ebp 43 pushl %ebx 44 pushl %ecx 45 pushl %edx 46 push %esi 47 push %edi 48 49 call _C_LABEL(prot_to_real) 50 .code16 51 52 xorl %ebx,%ebx 53 movl $0xe801,%eax 54 int $0x15 55 pushf 56 57 movw %si,%ax 58 orw %si,%bx 59 jz 1f /* if zero use configured values */ 60 movw %cx,%ax /* k below 16M (max 0x3c00 = 15MB) */ 61 movw %dx,%bx /* 64k above 16M */ 62 1: 63 popf 64 setc %bl 65 66 calll _C_LABEL(real_to_prot) 67 .code32 68 69 movl 8(%ebp),%edi 70 xorl %eax,%eax 71 movw %cx,%ax 72 stosl 73 movw %dx,%ax 74 stosl 75 movb %bl,%al 76 cbw 77 78 pop %edi 79 pop %esi 80 popl %edx 81 popl %ecx 82 popl %ebx 83 popl %ebp 84 ret 85 86 /* 87 * int getmementry(int *iterator, int buffer[5]) 88 * 89 * return: 0=ok, else error 90 * buffer[0]: start of memory chunk 91 * buffer[2]: length (bytes) 92 * buffer[4]: type 93 */ 94 ENTRY(getmementry) 95 pushl %ebp 96 movl %esp,%ebp 97 pushl %ebx 98 pushl %ecx 99 pushl %edx 100 push %esi 101 push %edi 102 103 movl 8(%ebp),%eax 104 movl 0(%eax),%ebx /* index */ 105 movl $20,%ecx /* Buffer size */ 106 movl $0x534d4150,%edx /* "SMAP" */ 107 movl 12(%ebp),%edi /* buffer address */ 108 109 call _C_LABEL(prot_to_real) 110 .code16 111 112 push %di 113 shrl $4,%edi 114 mov %ds,%ax 115 add %di,%ax 116 mov %ax,%es 117 pop %di 118 and $0xf,%di /* buffer addres now in ES:DI */ 119 120 movl $0xe820,%eax /* Some BIOS check EAX value */ 121 int $0x15 122 123 setc %cl 124 125 calll _C_LABEL(real_to_prot) 126 .code32 127 128 movl 8(%ebp),%eax 129 movl %ebx,0(%eax) /* updated index */ 130 xorl %eax,%eax 131 movb %cl,%al 132 133 pop %edi 134 pop %esi 135 popl %edx 136 popl %ecx 137 popl %ebx 138 popl %ebp 139 ret 140 141 /* 142 * int biosA20(void) 143 * 144 * return: 0=ok, else error 145 */ 146 ENTRY(biosA20) 147 pushl %ebp 148 movl %esp,%ebp 149 pushl %ebx 150 pushl %ecx 151 pushl %edx 152 push %esi 153 push %edi 154 155 call _C_LABEL(prot_to_real) 156 .code16 157 158 movl $0x2401,%eax 159 int $0x15 160 setc %cl 161 162 calll _C_LABEL(real_to_prot) 163 .code32 164 165 movzbl %cl,%eax 166 167 pop %edi 168 pop %esi 169 popl %edx 170 popl %ecx 171 popl %ebx 172 popl %ebp 173 ret 174
Indexes created Tue Sep 30 20:09:53 GMT 2025