1 /* 2 * Copyright (c) 1980 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 7 #ifndef lint 8 _sccsid:.asciz "@(#)tmboot.c 6.2 (Berkeley) 06/08/85" 9 #endif not lint 10 11 /* 12 * VAX tape boot block for distribution tapes 13 * works on unibus tm03 14 * 15 * reads a program from a tp directory on a tape and executes it 16 * program must be stripped of the header and is loaded ``bits as is'' 17 * you can return to this loader via ``ret'' as you are called ``calls $0,ent'' 18 */ 19 .set RELOC,0x70000 20 /* a.out defines */ 21 .set HDRSIZ,040 /* size of file header for VAX */ 22 .set MAGIC,0410 /* file type id in header */ 23 .set TSIZ,4 /* text size */ 24 .set DSIZ,8 /* data size */ 25 .set BSIZ,12 /* bss size */ 26 .set TENT,024 /* task header entry loc */ 27 /* tp directory definitions */ 28 .set FILSIZ,38 /* tp direc offset for file size */ 29 .set BNUM,44 /* tp dir offset for start block no. */ 30 .set ENTSIZ,64 /* size of 1 TP dir entry, bytes */ 31 .set PTHSIZ,32 /* size of TP path name, bytes */ 32 .set BLKSIZ,512 /* tape block size, bytes */ 33 .set NUMDIR,24 /* no. of dir blocks on tape */ 34 .set ENTBLK,8 /* no. of dir entries per tape block */ 35 /* processor registers and bits */ 36 .set RXCS,32 37 .set RXDB,33 38 .set TXCS,34 39 .set TXDB,35 40 .set RXCS_DONE,0x80 41 .set TXCS_RDY,0x80 42 .set TXCS_pr,7 /* bit position of TXCS ready bit */ 43 .set RXCS_pd,7 /* bit position of RXCS done bit */ 44 /* UBA registers */ 45 .set UBA_DPR1,68 46 .set UBA_MAP,2048 47 .set BNE,0x80000000 48 .set MRV,0x80000000 49 .set MR_BDP1,0x200000 50 /* TM UBA registers */ 51 .set TMER,0 52 .set TMCS,2 53 .set TMBC,4 54 .set TMBA,6 55 /* TM commands and bits */ 56 .set GO,1 57 .set TM_REW,016 58 .set TM_RCOM,02 59 .set TM_SREV,012 60 .set TM_DCLR,010000 61 .set TM_crdy,7 62 .set TM_gapsd,3 63 .set TMDENS,0 /* 1600 bpi */ 64 /* local stack variables */ 65 .set tapa,-4 /* desired tape addr */ 66 .set mtapa,-8 /* current tape addr */ 67 .set name,-8-PTHSIZ /* operator-typed file name */ 68 /* register usage */ 69 .set rUBA,r10 70 .set rTM,r11 71 /* ===== */ 72 73 /* initialization */ 74 init: 75 movl $RELOC,fp /* core loc to which to move this program */ 76 addl3 $name,fp,sp /* set stack pointer; leave room for locals */ 77 clrl r0 78 1: 79 movc3 $end,(r0),(fp) /* move boot up to relocated position */ 80 jmp start+RELOC 81 start: 82 bsbw rew /* rewind input tape */ 83 movab name(fp),r4 /* start of filename storage */ 84 movzbl $'=,r0 /* prompt character */ 85 bsbw putc /* output char to main console */ 86 /* read in a file name */ 87 movl r4,r1 /* loc at which to store file name */ 88 nxtc: 89 bsbw getc /* get input char's in file name */ 90 cmpb r0,$012 /* terminator ? */ 91 beql nullc 92 movb r0,(r1)+ 93 brb nxtc 94 nullc: 95 subl3 r4,r1,r9 /* size of path name */ 96 beql start /* dumb operator */ 97 clrb (r1)+ 98 incl r9 99 /* user-specified TP filename has been stored at name(fp) */ 100 /* read in entire tp directory contents into low core */ 101 dirred: 102 movl $8,tapa(fp) /* tp directory starts at block 8 */ 103 movl $(NUMDIR*BLKSIZ),r6 /* no. bytes in total dir */ 104 bsbw taper /* read no. bytes indicated */ 105 /* search entire directory for user-specified file name */ 106 clrl r5 /* dir buff loc = 0 */ 107 nxtdir: 108 cmpc3 r9,(r5),(r4) /* see if dir entry matches filename */ 109 beql fndfil /* found match */ 110 acbl $NUMDIR*BLKSIZ-1,$ENTSIZ,r5,nxtdir 111 /* see if done with tp dir */ 112 brw start /* entry not in directory; start over */ 113 /* found desired tp dir entry */ 114 fndfil: 115 movzwl BNUM(r5),tapa(fp) /* start block no., 2 bytes */ 116 addl2 $7,tapa(fp) /* skip 7 boot blocks */ 117 movzwl FILSIZ(r5),r6 /* low 2 bytes file size */ 118 insv FILSIZ-1(r5),$16,$8,r6 /* file size, high byte */ 119 cmpl r6,$RELOC-512 /* check if file fits below stack */ 120 blss filok /* file o.k. */ 121 brw start /* file too large */ 122 /* time to read in desired file from tape */ 123 filok: 124 movl r6,r7 /* save r6 */ 125 bsbb taper 126 bsbw rew 127 /* clear core */ 128 subl3 r7,$RELOC-4,r0 /* no. bytes to clear */ 129 1: 130 clrb (r7)+ 131 sobgtr r0,1b 132 /* time to jump to start of file & execute */ 133 addl3 $20,fp,ap 134 clrl r5 135 calls $0,(r5) 136 brw start 137 /* taper: movcTAPE (r6),tapa(fp),0 */ 138 rew2: 139 bsbb rew /* beginning of tape */ 140 taper0: 141 bsbb rrec /* advance 1 block; never want blk 0 */ 142 taper: 143 clrl r0 /* page no. */ 144 cmpl mtapa(fp),tapa(fp) /* current position .vs. desired */ 145 bgtr rew2 146 blss taper0 147 1: 148 bsbb rrec 149 acbl $1,$-BLKSIZ,r6,1b 150 rsb 151 /* rew: rewind the tape */ 152 rew: 153 clrl mtapa(fp) /* current position */ 154 movw $TM_REW+TMDENS+GO,TMCS(%rTM) 155 rsb 156 /* rrec: read 1 block from mag tape into page (r0) */ 157 rrec: 158 /* pushl r0; movzbl $'r,r0; bsbw putc; movl (sp)+,r0; */ 159 jsb tmquiet 160 movw $-BLKSIZ,TMBC(%rTM) 161 bisl3 $MRV|MR_BDP1,r0,UBA_MAP(%rUBA) 162 movw $0,TMBA(%rTM) 163 movw $TM_RCOM+TMDENS+GO,TMCS(%rTM) 164 jsb tmquiet 165 bisl2 $BNE,UBA_DPR1(%rUBA) 166 tstw TMER(%rTM) 167 jgeq 2f 168 mnegw $1,TMBC(%rTM) 169 movw $TM_SREV+TMDENS+GO,TMCS(%rTM) 170 jmp rrec 171 2: 172 incl r0 /* next page no. */ 173 incl mtapa(fp) /* mag tape block position */ 174 rsb 175 getc: 176 mfpr $RXCS,r0 177 bbc $RXCS_pd,r0,getc /* receiver ready ? */ 178 mfpr $RXDB,r0 179 extzv $0,$7,r0,r0 180 cmpb r0,$015 181 bneq putc 182 bsbb putc 183 movb $0,r0 184 bsbb putc 185 movb $012,r0 186 putc: 187 mfpr $TXCS,r2 188 bbc $TXCS_pr,r2,putc /* transmitter ready ? */ 189 extzv $0,$7,r0,r0 190 mtpr r0,$TXDB 191 rsb 192 tmquiet: 193 movw TMCS(%rTM),r2 194 bbc $TM_crdy,r2,tmquiet 195 1: 196 movw TMER(%rTM),r2 197 blbc r2,1b /* low bit == TUR */ 198 bbs $TM_gapsd,r2,1b 199 rsb 200 end: 201