wdboot.S revision 1.1.4.2
1 /* $NetBSD: wdboot.S,v 1.1.4.2 2004/08/03 10:33:35 skrll 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 tstb %d5 59 beqs 0f | no boot preference 60 cmpb #0x20,%d5 61 bnes exit | bootpref != NetBSD 62 63 0: btst #3,%d0 | Alternate? 64 bnes exit 65 subql #1,%d0 66 movl %d0,%a3 | autoboot flag 67 68 movl _membot:w,%d3 69 lea MAXBOT,%a4 70 cmpl %a4,%d3 71 bhis exit | membot > MAXBOT 72 73 movl _memtop:w,%d3 74 cmpl #MINTOP,%d3 75 blts exit | memtop < MINTOP 76 77 andw #-4,%d3 78 movl %d3,%a0 79 movl %sp,%a0@- 80 movl %a0,%sp | set new stack 81 82 movq #NSEC,%d5 | sector count 83 movq #1,%d6 | first sector 84 bsrs rds0 85 tstl %d0 86 bnes 0f 87 /* 88 * loader (readsector, disklabel, autoboot) 89 */ 90 pea %a3@ | autoboot 91 pea %a4@(LBLST-MAXBOT) | disklabel 92 pea %pc@(rds1) | readsector 93 jsr %a4@(BXXST-MAXBOT) 94 lea %sp@(12),%sp | NetBSD not booted 95 96 0: movl %sp@,%sp | restore BIOS stack 97 tstl %d0 98 bmis exit 99 movl %d0,%sp@(8) | new boot preference 100 101 exit: movml %sp@+,%d3-%d5/%d7 102 rts 103 104 /* 105 * int readsec (void *buffer, u_int offset, u_int count); 106 */ 107 rds1: movml %d2-%d7/%a2-%a6,%sp@- 108 movl %pc@(regsav),%a0 109 movml %a0@,%d3-%d5/%d7 110 movl %sp@(48),%a4 | buffer 111 movl %sp@(52),%d6 | offset 112 movl %sp@(56),%d3 | count 113 0: movl #255,%d5 114 cmpl %d5,%d3 115 bccs 1f 116 movl %d3,%d5 117 1: bsrs rds0 118 tstl %d0 119 bnes 2f 120 addl #(255*512),%a4 121 addl %d5,%d6 122 subl %d5,%d3 123 bnes 0b 124 2: movml %sp@+,%d2-%d7/%a2-%a6 125 rts 126 /* 127 * in: d4 (target) d5 (count), d6 (offset), a4 (buffer) 128 * out: d0 (<= 0) 129 * mod: d0, d1, d2, a0, a1, a5, a6 130 */ 131 rds0: lea %pc@(dpar),%a6 132 tstb %a6@ 133 bnes 0f 134 movb %d4,%d0 135 andb #1,%d0 136 aslb #4,%d0 137 orb #0xa0,%d0 138 movb %d0,idesdh:l 139 movl %a4,%a0 140 movq #0,%d1 141 movb #0,idedor:l 142 movb #0xec,idecr:l | IDENTIFY DRIVE 143 bsrs wait 144 bnes err 145 movb %a4@(7),%a6@ | tracks/cylinder 146 movb %a4@(13),%a6@(1) | sectors/track 147 0: movl %d6,%d1 148 movq #0,%d0 149 movb %a6@(1),%d0 150 movq #0,%d2 151 movb %a6@,%d2 152 mulu %d0,%d2 153 divu %d2,%d1 154 movb %d1,idecl:l 155 lsrl #8,%d1 156 movb %d1,idech:l 157 lsrl #8,%d1 158 divu %d0,%d1 159 movb %d4,%d0 160 andb #1,%d0 161 aslb #4,%d0 162 orb %d0,%d1 163 orb #0xa0,%d1 164 movb %d1,idesdh:l 165 swap %d1 166 addqw #1,%d1 167 movb %d1,idesn:l 168 movl %a4,%a0 169 movb %d5,idesc:l 170 movw %d5,%d1 171 subqw #1,%d1 172 movb #0,idedor:l 173 movb #0x20,idecr:l 174 wait: movl #0x7d0,%d0 175 addl _hz_200:w,%d0 176 2: btst #5,gpip:w 177 beqs 3f 178 cmpl _hz_200:w,%d0 179 bhis 2b 180 err: movq #-1,%d0 181 rts 182 3: movb idesr:l,%d0 183 btst #0,%d0 184 bnes err 185 btst #3,%d0 186 beqs err 187 movq #63,%d0 188 lea idedr:l,%a1 189 4: movw %a1@,%a0@+ 190 movw %a1@,%a0@+ 191 movw %a1@,%a0@+ 192 movw %a1@,%a0@+ 193 dbra %d0,4b 194 dbra %d1,wait 195 movq #0,%d0 196 rts 197 198 regsav: .long 0 199 200 fill: .space 30 201 202 dpar: .byte 0 | tracks/cylinder 203 .byte 0 | sectors/track 204 205 .ascii "NetBSD" 206 hd_siz: .long 0 207 p0_dsc: .long 0, 0, 0 208 p1_dsc: .long 0, 0, 0 209 p2_dsc: .long 0, 0, 0 210 p3_dsc: .long 0, 0, 0 211 bsl_st: .long 0 212 bsl_sz: .long 0 213 .word 0 214 end: 215
Indexes created Mon Oct 20 15:10:11 GMT 2025