mbr.S revision 1.1.6.2
1 1.1.6.2 rpaulo /* $NetBSD: mbr.S,v 1.1.6.2 2006/09/09 02:40:57 rpaulo Exp $ */ 2 1.1.6.2 rpaulo 3 1.1.6.2 rpaulo /*- 4 1.1.6.2 rpaulo * Copyright (c) 2005 NONAKA Kimihiro 5 1.1.6.2 rpaulo * All rights reserved. 6 1.1.6.2 rpaulo * 7 1.1.6.2 rpaulo * Redistribution and use in source and binary forms, with or without 8 1.1.6.2 rpaulo * modification, are permitted provided that the following conditions 9 1.1.6.2 rpaulo * are met: 10 1.1.6.2 rpaulo * 1. Redistributions of source code must retain the above copyright 11 1.1.6.2 rpaulo * notice, this list of conditions and the following disclaimer. 12 1.1.6.2 rpaulo * 2. Redistributions in binary form must reproduce the above copyright 13 1.1.6.2 rpaulo * notice, this list of conditions and the following disclaimer in the 14 1.1.6.2 rpaulo * documentation and/or other materials provided with the distribution. 15 1.1.6.2 rpaulo * 16 1.1.6.2 rpaulo * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17 1.1.6.2 rpaulo * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 1.1.6.2 rpaulo * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 1.1.6.2 rpaulo * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20 1.1.6.2 rpaulo * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 1.1.6.2 rpaulo * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 1.1.6.2 rpaulo * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 1.1.6.2 rpaulo * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 1.1.6.2 rpaulo * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 1.1.6.2 rpaulo * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 1.1.6.2 rpaulo * SUCH DAMAGE. 27 1.1.6.2 rpaulo */ 28 1.1.6.2 rpaulo 29 1.1.6.2 rpaulo #include <machine/asm.h> 30 1.1.6.2 rpaulo #include <sys/bootblock.h> 31 1.1.6.2 rpaulo 32 1.1.6.2 rpaulo ENTRY(start) 33 1.1.6.2 rpaulo mova mbr_end, r0 34 1.1.6.2 rpaulo mov r0, r11 /* r11: relocate address */ 35 1.1.6.2 rpaulo 36 1.1.6.2 rpaulo mov.w mbr_size, r2 37 1.1.6.2 rpaulo sub r2, r0 38 1.1.6.2 rpaulo mov r0, r10 /* r10: loaded address */ 39 1.1.6.2 rpaulo 40 1.1.6.2 rpaulo mov.w stack_offset, r1 41 1.1.6.2 rpaulo add r1, r0 42 1.1.6.2 rpaulo mov r0, r15 /* r15: stack pointer */ 43 1.1.6.2 rpaulo 44 1.1.6.2 rpaulo /* relocate code */ 45 1.1.6.2 rpaulo mova jmp_start, r0 46 1.1.6.2 rpaulo mov r0, r13 47 1.1.6.2 rpaulo add r2, r13 /* calc jump address */ 48 1.1.6.2 rpaulo 49 1.1.6.2 rpaulo mov r10, r0 50 1.1.6.2 rpaulo mov r11, r1 51 1.1.6.2 rpaulo 1: mov.b @r0+, r3 52 1.1.6.2 rpaulo dt r2 53 1.1.6.2 rpaulo mov.b r3, @r1 54 1.1.6.2 rpaulo bf/s 1b 55 1.1.6.2 rpaulo add #1, r1 56 1.1.6.2 rpaulo 57 1.1.6.2 rpaulo jmp @r13 58 1.1.6.2 rpaulo nop 59 1.1.6.2 rpaulo 60 1.1.6.2 rpaulo .align 2 61 1.1.6.2 rpaulo jmp_start: 62 1.1.6.2 rpaulo /* enable cache */ 63 1.1.6.2 rpaulo mov #0, r4 64 1.1.6.2 rpaulo mov #6, r0 65 1.1.6.2 rpaulo trapa #0x3f 66 1.1.6.2 rpaulo 67 1.1.6.2 rpaulo #ifndef NO_BANNER 68 1.1.6.2 rpaulo /* print banner */ 69 1.1.6.2 rpaulo mova banner, r0 70 1.1.6.2 rpaulo bsr message_crlf 71 1.1.6.2 rpaulo mov r0, r4 72 1.1.6.2 rpaulo #endif 73 1.1.6.2 rpaulo 74 1.1.6.2 rpaulo /* search bootable partition */ 75 1.1.6.2 rpaulo mov.w part_offset, r12 76 1.1.6.2 rpaulo add r11, r12 /* r12: pointer to partition entry */ 77 1.1.6.2 rpaulo mov #MBR_PART_COUNT, r8 /* r8: partition loop counter */ 78 1.1.6.2 rpaulo loop_part: 79 1.1.6.2 rpaulo mov.b @(4, r12), r0 80 1.1.6.2 rpaulo cmp/eq #MBR_PTYPE_UNUSED, r0 81 1.1.6.2 rpaulo bt next_part 82 1.1.6.2 rpaulo 83 1.1.6.2 rpaulo /* check active partition */ 84 1.1.6.2 rpaulo mov.b @(0, r12), r0 85 1.1.6.2 rpaulo cmp/eq #0x80, r0 86 1.1.6.2 rpaulo bf next_part 87 1.1.6.2 rpaulo 88 1.1.6.2 rpaulo /* found bootable partition */ 89 1.1.6.2 rpaulo mov.w @(8, r12), r0 /* load unaligned 32bit data */ 90 1.1.6.2 rpaulo mov r0, r1 91 1.1.6.2 rpaulo mov.w @(10, r12), r0 92 1.1.6.2 rpaulo extu.w r1, r1 93 1.1.6.2 rpaulo shll16 r0 94 1.1.6.2 rpaulo or r1, r0 95 1.1.6.2 rpaulo 96 1.1.6.2 rpaulo mov r0, r3 97 1.1.6.2 rpaulo mova found_sector, r0 98 1.1.6.2 rpaulo bra boot_lba 99 1.1.6.2 rpaulo mov.l r3, @r0 100 1.1.6.2 rpaulo 101 1.1.6.2 rpaulo next_part: 102 1.1.6.2 rpaulo dt r8 103 1.1.6.2 rpaulo bf/s loop_part 104 1.1.6.2 rpaulo add #16, r12 105 1.1.6.2 rpaulo 106 1.1.6.2 rpaulo noos_error: 107 1.1.6.2 rpaulo /* Not found bootable partition */ 108 1.1.6.2 rpaulo mova ERR_NOOS, r0 109 1.1.6.2 rpaulo error: 110 1.1.6.2 rpaulo bsr message_crlf 111 1.1.6.2 rpaulo mov r0, r4 112 1.1.6.2 rpaulo 99: bra 99b 113 1.1.6.2 rpaulo nop 114 1.1.6.2 rpaulo 115 1.1.6.2 rpaulo read_error: 116 1.1.6.2 rpaulo bra error 117 1.1.6.2 rpaulo mova ERR_READ, r0 118 1.1.6.2 rpaulo 119 1.1.6.2 rpaulo message_crlf: 120 1.1.6.2 rpaulo mov #32, r0 121 1.1.6.2 rpaulo trapa #0x3f 122 1.1.6.2 rpaulo mova crlf, r0 123 1.1.6.2 rpaulo mov r0, r4 124 1.1.6.2 rpaulo mov #32, r0 125 1.1.6.2 rpaulo trapa #0x3f 126 1.1.6.2 rpaulo rts 127 1.1.6.2 rpaulo nop 128 1.1.6.2 rpaulo 129 1.1.6.2 rpaulo read_sector_lba: 130 1.1.6.2 rpaulo mov #1, r7 131 1.1.6.2 rpaulo mov #2, r0 132 1.1.6.2 rpaulo trapa #0x3f 133 1.1.6.2 rpaulo tst r0, r0 134 1.1.6.2 rpaulo bf read_error 135 1.1.6.2 rpaulo rts 136 1.1.6.2 rpaulo nop 137 1.1.6.2 rpaulo 138 1.1.6.2 rpaulo boot_lba: 139 1.1.6.2 rpaulo /* read PBR sector */ 140 1.1.6.2 rpaulo mova found_sector, r0 141 1.1.6.2 rpaulo mov #0x40, r4 142 1.1.6.2 rpaulo mov.l @r0, r5 143 1.1.6.2 rpaulo bsr read_sector_lba 144 1.1.6.2 rpaulo mov r10, r6 145 1.1.6.2 rpaulo 146 1.1.6.2 rpaulo /* flush cache */ 147 1.1.6.2 rpaulo mov #0, r4 148 1.1.6.2 rpaulo mov #6, r0 149 1.1.6.2 rpaulo trapa #0x3f 150 1.1.6.2 rpaulo 151 1.1.6.2 rpaulo /* check signature */ 152 1.1.6.2 rpaulo mov.b @(0, r10), r0 153 1.1.6.2 rpaulo tst r0, r0 154 1.1.6.2 rpaulo bt noos_error /* first byte non-zero */ 155 1.1.6.2 rpaulo mov.w magic_offset, r0 156 1.1.6.2 rpaulo mov.w @(r0, r10), r1 157 1.1.6.2 rpaulo mov.w magic, r2 158 1.1.6.2 rpaulo cmp/eq r1, r2 159 1.1.6.2 rpaulo bf noos_error /* magic */ 160 1.1.6.2 rpaulo 161 1.1.6.2 rpaulo /* now jump to PBR */ 162 1.1.6.2 rpaulo mov r10, r0 163 1.1.6.2 rpaulo jmp @r10 164 1.1.6.2 rpaulo nop 165 1.1.6.2 rpaulo 166 1.1.6.2 rpaulo 167 1.1.6.2 rpaulo .align 1 168 1.1.6.2 rpaulo mbr_size: .word mbr_end - _C_LABEL(start) 169 1.1.6.2 rpaulo .align 1 170 1.1.6.2 rpaulo stack_offset: .word 0x1000 171 1.1.6.2 rpaulo .align 1 172 1.1.6.2 rpaulo part_offset: .word MBR_PART_OFFSET 173 1.1.6.2 rpaulo .align 1 174 1.1.6.2 rpaulo magic_offset: .word MBR_MAGIC_OFFSET 175 1.1.6.2 rpaulo 176 1.1.6.2 rpaulo .align 2 177 1.1.6.2 rpaulo found_sector: .long 0 178 1.1.6.2 rpaulo 179 1.1.6.2 rpaulo #ifndef NO_BANNER 180 1.1.6.2 rpaulo .align 2 181 1.1.6.2 rpaulo banner: .asciz "\r\nNetBSD MBR boot" 182 1.1.6.2 rpaulo #endif 183 1.1.6.2 rpaulo .align 2 184 1.1.6.2 rpaulo crlf: .asciz "\r\n" 185 1.1.6.2 rpaulo 186 1.1.6.2 rpaulo .align 2 187 1.1.6.2 rpaulo ERR_INVPART: .asciz "No active partition" 188 1.1.6.2 rpaulo .align 2 189 1.1.6.2 rpaulo ERR_READ: .asciz "Disk read error" 190 1.1.6.2 rpaulo .align 2 191 1.1.6.2 rpaulo ERR_NOOS: .asciz "No operating system" 192 1.1.6.2 rpaulo 193 1.1.6.2 rpaulo 194 1.1.6.2 rpaulo /* space for mbr_dsn */ 195 1.1.6.2 rpaulo . = _C_LABEL(start) + MBR_DSN_OFFSET 196 1.1.6.2 rpaulo .long 0 197 1.1.6.2 rpaulo 198 1.1.6.2 rpaulo /* mbr_bootsel_magic */ 199 1.1.6.2 rpaulo . = _C_LABEL(start) + MBR_BS_MAGIC_OFFSET 200 1.1.6.2 rpaulo .word MBR_BS_MAGIC 201 1.1.6.2 rpaulo 202 1.1.6.2 rpaulo /* 203 1.1.6.2 rpaulo * MBR partition table 204 1.1.6.2 rpaulo */ 205 1.1.6.2 rpaulo . = _C_LABEL(start) + MBR_PART_OFFSET 206 1.1.6.2 rpaulo _pbr_part0: 207 1.1.6.2 rpaulo .byte 0, 0, 0, 0, 0, 0, 0, 0 208 1.1.6.2 rpaulo .byte 0, 0, 0, 0, 0, 0, 0, 0 209 1.1.6.2 rpaulo _pbr_part1: 210 1.1.6.2 rpaulo .byte 0, 0, 0, 0, 0, 0, 0, 0 211 1.1.6.2 rpaulo .byte 0, 0, 0, 0, 0, 0, 0, 0 212 1.1.6.2 rpaulo _pbr_part2: 213 1.1.6.2 rpaulo .byte 0, 0, 0, 0, 0, 0, 0, 0 214 1.1.6.2 rpaulo .byte 0, 0, 0, 0, 0, 0, 0, 0 215 1.1.6.2 rpaulo _pbr_part3: 216 1.1.6.2 rpaulo .byte 0, 0, 0, 0, 0, 0, 0, 0 217 1.1.6.2 rpaulo .byte 0, 0, 0, 0, 0, 0, 0, 0 218 1.1.6.2 rpaulo 219 1.1.6.2 rpaulo . = _C_LABEL(start) + MBR_MAGIC_OFFSET 220 1.1.6.2 rpaulo magic: 221 1.1.6.2 rpaulo .word MBR_MAGIC 222 1.1.6.2 rpaulo mbr_end: 223
Indexes created Wed Oct 15 07:09:58 GMT 2025