sdboot.S revision 1.2
1 /* $NetBSD: sdboot.S,v 1.2 2005/12/11 12:17:02 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Waldi Ravens 5 * 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 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Waldi Ravens. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include "xxboot.h" 34 35 #ifdef __ELF__ 36 .globl _start, main, fill 37 38 .text 39 _start: 40 #else 41 .globl start, main, fill 42 43 .text 44 start: 45 #endif 46 /* 47 * in: d3 ('DMAr' flag), d4 (SCSI target), d5 (boot pref), d7 (ACSI target) 48 */ 49 main: lea %pc@(regsav),%a0 50 movml %d3-%d5/%d7,%sp@- 51 movl %sp,%a0@ 52 53 movw #-1,%sp@- 54 movw #Kbshift,%sp@- 55 trap #BIOS 56 addql #4,%sp 57 58 cmpl #0x444d4172,%d3 | SCSI bootdev? 59 beqs 0f 60 movq #-1,%d4 | no, ACSI 61 bras 1f 62 63 0: tstb %d5 64 beqs 1f | no boot preference 65 cmpb #0x20,%d5 66 bnes exit | bootpref != NetBSD 67 68 1: btst #3,%d0 | Alternate? 69 bnes exit 70 subql #1,%d0 71 movl %d0,%a3 | autoboot flag 72 73 movl _membot:w,%d0 74 lea MAXBOT,%a4 75 cmpl %a4,%d0 76 bhis exit | membot > MAXBOT 77 78 movl _memtop:w,%d0 79 cmpl #MINTOP,%d0 80 blts exit | memtop < MINTOP 81 82 andw #-4,%d0 83 movl %d0,%a0 84 movl %sp,%a0@- 85 movl %a0,%sp | set new stack 86 87 movq #NSEC,%d5 | sector count 88 movq #1,%d6 | first sector 89 bsrs rds0 90 tstl %d0 91 bnes 0f 92 /* 93 * loader (readsector, disklabel, autoboot) 94 */ 95 pea %a3@ | autoboot 96 pea %a4@(LBLST-MAXBOT) | disklabel 97 pea %pc@(rds1) | readsector 98 jsr %a4@(BXXST-MAXBOT) 99 lea %sp@(12),%sp | NetBSD not booted 100 101 0: movl %sp@,%sp | restore BIOS stack 102 tstl %d0 103 bmis exit 104 movl %d0,%sp@(8) | new boot preference 105 106 exit: movml %sp@+,%d3-%d5/%d7 107 rts 108 109 /* 110 * int readsec (void *buffer, u_int offset, u_int count); 111 */ 112 rds1: movml %d2-%d7/%a2-%a6,%sp@- 113 movl %pc@(regsav),%a0 114 movml %a0@,%d3-%d5/%d7 115 movl %sp@(48),%a4 | buffer 116 movl %sp@(52),%d6 | offset 117 movl %sp@(56),%d3 | count 118 0: movl #255,%d5 119 cmpl %d5,%d3 120 bccs 1f 121 movl %d3,%d5 122 1: bsrs rds0 123 tstl %d0 124 bnes 2f 125 addl #(255*512),%a4 126 addl %d5,%d6 127 subl %d5,%d3 128 bnes 0b 129 2: movml %sp@+,%d2-%d7/%a2-%a6 130 rts 131 /* 132 * in: d4/d7 (target) d5 (count), d6 (offset), a4 (buffer) 133 * out: d0 (<= 0) 134 * mod: d0, d1, d2, a0, a5, a6 135 */ 136 rds0: tstl %d4 137 bmis 0f 138 movw %d4,%sp@- | device 139 pea %a4@ | buffer 140 movw %d5,%sp@- | count 141 movl %d6,%sp@- | offset 142 movw #DMAread,%sp@- 143 trap #XBIOS 144 lea %sp@(14),%sp 145 rts 146 147 0: st flock:w 148 movl _hz_200:w,%d0 149 addql #2,%d0 150 1: cmpl _hz_200:w,%d0 151 bccs 1b 152 movml %d6/%a4,%sp@- 153 lea dmahi:w,%a6 154 movb %sp@(7),%a6@(4) 155 movb %sp@(6),%a6@(2) 156 movb %sp@(5),%a6@ 157 lea %pc@(r0com),%a6 158 movb %sp@(1),%a6@(1) 159 movb %sp@(2),%a6@(5) 160 movb %sp@(3),%a6@(9) 161 movb %d5,%a6@(13) 162 addql #8,%sp 163 lea dmodus:w,%a6 164 lea daccess:w,%a5 165 movw #0x198,%a6@ 166 movw #0x098,%a6@ 167 movw %d5,%a5@ 168 movw #0x88,%a6@ 169 movq #0,%d0 170 movb %d7,%d0 171 orb #0x08,%d0 172 swap %d0 173 movw #0x8a,%d0 174 bsrs shake 175 lea %pc@(r0com),%a0 176 movq #3,%d2 177 2: movl %a0@+,%d0 178 bsrs shake 179 dbra %d2,2b 180 movq #0x0a,%d0 181 movl %d0,%a5@ 182 movl #0x190,%d1 183 bsrs wait 184 movw #0x8a,%a6@ 185 movw %a5@,%d0 186 andw #0xff,%d0 187 beqs 0f 188 r0err: movq #-1,%d0 189 0: movw #0x80,%a6@ 190 clrb flock:w 191 r0ret: rts 192 193 shake: movl %d0,%a5@ 194 movq #0x0a,%d1 195 wait: addl _hz_200:w,%d1 196 0: btst #5,gpip:w 197 beqs r0ret 198 cmpl _hz_200:w,%d1 199 bccs 0b 200 addql #4,%sp 201 bras r0err 202 203 r0com: .long 0x0000008a 204 .long 0x0000008a 205 .long 0x0000008a 206 .long 0x0001008a 207 208 regsav: .long 0 209 210 fill: .space 24 211 212 .ascii "NetBSD" 213 hd_siz: .long 0 214 p0_dsc: .long 0, 0, 0 215 p1_dsc: .long 0, 0, 0 216 p2_dsc: .long 0, 0, 0 217 p3_dsc: .long 0, 0, 0 218 bsl_st: .long 0 219 bsl_sz: .long 0 220 .word 0 221 end: 222
Indexes created Wed Oct 22 13:09:56 GMT 2025