1 /* 2 * Copyright (c) 1982, 1986 Regents of the University of California. 3 * All rights reserved. The Berkeley software License Agreement 4 * specifies the terms and conditions for redistribution. 5 * 6 * @(#)srt0.c 7.8 (Berkeley) 05/05/91 7 */ 8 9 #include "../include/mtpr.h" 10 #define LOCORE 11 #include "../include/cpu.h" 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 */ 18 19 .globl _end 20 .globl _edata 21 .globl _main 22 .globl __rtt 23 .globl _configure 24 .globl _cpu 25 .globl _firstopen 26 .globl _boothowto 27 .globl _bootdev 28 29 .set HIGH,31 # mask for total disable 30 31 entry: .globl entry 32 nop; nop # .word 0x0101 33 mtpr $HIGH,$IPL # just in case 34 35 #ifdef REL 36 # we need to do special stuff on microvaxen 37 mfpr $SID,r0 38 cmpzv $24,$8,r0,$VAX_630 39 beql 1f 40 cmpzv $24,$8,r0,$VAX_650 41 bneq 2f 42 43 /* 44 * Were we booted by VMB? If so, r11 is not boothowto, 45 * but rather the address of the `Extended RPB' (see KA630 46 * User's Manual, pp 3-21). These tests were devised by 47 * richl@tektronix, 11/10/87. 48 */ 49 1: 50 cmpl (r11),r11 # if boothowto, r11 will be small 51 bneq 2f # and these will not fault 52 cmpl 4(r11),$0 53 bneq 2f 54 cmpl 8(r11),$-1 55 bneq 2f 56 tstl 0xc(r11) 57 bneq 2f 58 59 /* 60 * Booted by VMB: get flags from extended rpb. 61 * We can only guess at the boot device (here ra(0,0)). 62 */ 63 movl 0x30(r11),r11 64 movl $9,r10 # device = ra(0,0) 65 2: 66 movl $RELOC,sp 67 #else 68 movl $RELOC-0x2400,sp 69 #endif 70 start: 71 #ifndef REL 72 /* 73 * Clear bss segment 74 */ 75 movl aedata,r0 76 clr: 77 clrl (r0)+ 78 cmpl r0,sp 79 jlss clr 80 #else 81 /* 82 * `entry' below generates a pc-relative reference to the 83 * code, so this works no matter where we are now. 84 * Clear bss segment *after* moving text and data. 85 */ 86 movc3 aedata,entry,(sp) 87 dclr: 88 clrl (r3)+ 89 cmpl r3,$_end 90 jlss dclr 91 /* this loop shouldn't be necessary, but is when booting from an ra81 */ 92 xclr: 93 clrl (r3)+ 94 cmpl r3,$0x100000 95 jlss xclr 96 jmp *abegin 97 begin: 98 #endif 99 movl r11,_boothowto 100 movl r10,_bootdev 101 again: 102 mtpr $0,$SCBB 103 calls $0,_configure 104 movl $1,_firstopen 105 calls $0,_main 106 #ifdef REL 107 jmp again 108 #else 109 ret 110 #endif 111 112 .data 113 #ifdef REL 114 abegin: .long begin 115 aedata: .long _edata-RELOC 116 #else 117 aedata: .long _edata 118 #endif 119 _bootdev: .long 0 120 _boothowto: .long 0 121 .text 122 123 __rtt: 124 .word 0x0 125 #ifdef REL 126 halt 127 #else 128 jmp start 129 #endif 130 131 .globl _badaddr 132 _badaddr: 133 .word 0 134 movl $1,r0 135 movl 4(ap),r3 136 movl 8(ap),r4 137 movl $4,r2 138 movab 9f,(r2) 139 bbc $0,r4,1f; tstb (r3) 140 1: bbc $1,r4,1f; tstw (r3) 141 1: bbc $2,r4,1f; tstl (r3) 142 1: clrl r0 # made it w/o machine checks 143 2: movl $4,r2 144 clrl (r2) 145 ret 146 .align 2 147 9: 148 casel _cpu,$1,$VAX_MAX 149 0: 150 .word 8f-0b # 1 is 780 151 .word 5f-0b # 2 is 750 152 .word 5f-0b # 3 is 730 153 .word 6f-0b # 4 is 8600 154 .word 5f-0b # 5 is 8200 155 .word 1f-0b # 6 is 8800 156 .word 1f-0b # 7 is 610 157 .word 5f-0b # 8 is 630 158 .word 1f-0b # 9 is ??? 159 .word 1f-0b # 10 is 650 160 5: 161 mtpr $0xf,$MCESR 162 brb 1f 163 6: 164 mtpr $0,$EHSR 165 brb 1f 166 8: 167 mtpr $0,$SBIFS 168 1: 169 addl2 (sp)+,sp # discard mchchk trash 170 movab 2b,(sp) 171 rei 172 173 /* 174 * Short assembly versions of strcmp, strcpy, and strlen 175 * that do not use special instructions. 176 */ 177 .globl _strcmp 178 _strcmp: 179 .word 0 180 movq 4(ap),r0 181 0: cmpb (r0),(r1)+ 182 bneq 1f 183 tstb (r0)+ 184 bneq 0b 185 clrl r0 186 ret 187 1: cvtbl (r0),r0 188 cvtbl -(r1),r1 189 subl2 r1,r0 190 ret 191 192 .globl _strcpy 193 _strcpy: 194 .word 0 195 movq 4(ap),r0 196 0: movb (r1)+,(r0)+ 197 bneq 0b 198 movl 4(ap),r0 199 ret 200 201 .globl _strlen 202 _strlen: 203 .word 0 204 movl 4(ap),r0 205 0: tstb (r0)+ 206 bneq 0b 207 decl r0 208 subl2 4(ap),r0 209 ret 210