1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * William Jolitz. 7 * 8 * %sccs.include.redist.c% 9 * 10 * @(#)srt0.c 8.1 (Berkeley) 06/11/93 11 */ 12 13 /* 14 * Startup code for standalone system 15 * Non-relocating version -- for programs which are loaded by boot 16 * Relocating version for boot 17 * Small relocating version for "micro" boot 18 */ 19 20 .globl _end 21 .globl _edata 22 .globl _main 23 .globl __rtt 24 .globl _exit 25 .globl _bootdev 26 .globl _cyloffset 27 28 #ifdef SMALL 29 /* where the disklabel goes if we have one */ 30 .globl _disklabel 31 _disklabel: 32 .space 512 33 #endif 34 35 entry: .globl entry 36 .globl start 37 38 #if defined(REL) && !defined(SMALL) 39 40 /* relocate program and enter at symbol "start" */ 41 42 #movl $entry-RELOC,%esi # from beginning of ram 43 movl $0,%esi 44 #movl $entry,%edi # to relocated area 45 movl $ RELOC,%edi # to relocated area 46 # movl $_edata-RELOC,%ecx # this much 47 movl $64*1024,%ecx 48 cld 49 rep 50 movsb 51 # relocate program counter to relocation base 52 pushl $start 53 ret 54 #endif 55 56 start: 57 58 /* setup stack pointer */ 59 60 #ifdef REL 61 leal 4(%esp),%eax /* ignore old pc */ 62 movl $ RELOC-4*4,%esp 63 /* copy down boot parameters */ 64 movl %esp,%ebx 65 pushl $3*4 66 pushl %ebx 67 pushl %eax 68 call _bcopy 69 movl %ebx,%esp 70 #else 71 /* save old stack state */ 72 movl %esp,savearea 73 movl %ebp,savearea+4 74 movl $ RELOC-0x2400,%esp 75 #endif 76 77 /* clear memory as needed */ 78 79 movl %esp,%esi 80 #ifdef REL 81 82 /* 83 * Clear Bss and up to 64K heap 84 */ 85 movl $64*1024,%ebx 86 movl $_end,%eax # should be movl $_end-_edata but ... 87 subl $_edata,%eax 88 addl %ebx,%eax 89 pushl %eax 90 pushl $_edata 91 call _bzero 92 93 /* 94 * Clear 64K of stack 95 */ 96 movl %esi,%eax 97 subl %ebx,%eax 98 subl $5*4,%ebx 99 pushl %ebx 100 pushl %eax 101 call _bzero 102 #else 103 movl $_edata,%edx 104 movl %esp,%eax 105 subl %edx,%eax 106 pushl %edx 107 pushl %esp 108 call _bzero 109 #endif 110 movl %esi,%esp 111 112 pushl $0 113 popf 114 115 #ifndef SMALL 116 call _kbdreset /* resets keyboard and gatea20 brain damage */ 117 #endif 118 119 call _main 120 jmp 1f 121 122 .data 123 _bootdev: .long 0 124 _cyloffset: .long 0 125 savearea: .long 0,0 # sp & bp to return to 126 .text 127 #ifndef SMALL 128 .globl _getchar 129 #endif 130 .globl _wait 131 132 __rtt: 133 #ifndef SMALL 134 call _getchar 135 #else 136 _exit: 137 pushl $1000000 138 call _wait 139 popl %eax 140 #endif 141 movl $-7,%eax 142 jmp 1f 143 #ifndef SMALL 144 _exit: 145 call _getchar 146 #endif 147 movl 4(%esp),%eax 148 1: 149 #ifdef REL 150 #ifndef SMALL 151 call _reset_cpu 152 #endif 153 movw $0x1234,%ax 154 movw %ax,0x472 # warm boot 155 movl $0,%esp # segment violation 156 ret 157 #else 158 movl savearea,%esp 159 movl savearea+4,%ebp 160 ret 161 #endif 162 163 .globl _inb 164 _inb: movl 4(%esp),%edx 165 subl %eax,%eax # clr eax 166 inb %dx,%al 167 ret 168 169 .globl _outb 170 _outb: movl 4(%esp),%edx 171 movl 8(%esp),%eax 172 outb %al,%dx 173 ret 174 175 .globl ___udivsi3 176 ___udivsi3: 177 movl 4(%esp),%eax 178 xorl %edx,%edx 179 divl 8(%esp) 180 ret 181 182 .globl ___divsi3 183 ___divsi3: 184 movl 4(%esp),%eax 185 xorl %edx,%edx 186 cltd 187 idivl 8(%esp) 188 ret 189 190 # 191 # bzero (base,cnt) 192 # 193 194 .globl _bzero 195 _bzero: 196 pushl %edi 197 movl 8(%esp),%edi 198 movl 12(%esp),%ecx 199 movb $0x00,%al 200 cld 201 rep 202 stosb 203 popl %edi 204 ret 205 206 # 207 # bcopy (src,dst,cnt) 208 # NOTE: does not (yet) handle overlapped copies 209 # 210 211 .globl _bcopy 212 _bcopy: 213 pushl %esi 214 pushl %edi 215 movl 12(%esp),%esi 216 movl 16(%esp),%edi 217 movl 20(%esp),%ecx 218 cld 219 rep 220 movsb 221 popl %edi 222 popl %esi 223 ret 224 225 # insw(port,addr,cnt) 226 .globl _insw 227 _insw: 228 pushl %edi 229 movw 8(%esp),%dx 230 movl 12(%esp),%edi 231 movl 16(%esp),%ecx 232 cld 233 nop 234 .byte 0x66,0xf2,0x6d # rep insw 235 nop 236 movl %edi,%eax 237 popl %edi 238 ret 239 240 # outsw(port,addr,cnt) 241 .globl _outsw 242 _outsw: 243 pushl %esi 244 movw 8(%esp),%dx 245 movl 12(%esp),%esi 246 movl 16(%esp),%ecx 247 cld 248 nop 249 .byte 0x66,0xf2,0x6f # rep outsw 250 nop 251 movl %esi,%eax 252 popl %esi 253 ret 254 255