Commit | Line | Data |
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b1078c35 | 1 | /* |
0880b18e | 2 | * Copyright (c) 1980, 1986 Regents of the University of California. |
b1078c35 KM |
3 | * All rights reserved. The Berkeley software License Agreement |
4 | * specifies the terms and conditions for redistribution. | |
5 | */ | |
6 | ||
0880b18e | 7 | /* "@(#)mtboot.c 7.1 (Berkeley) %G%" */ |
735b8f44 SL |
8 | |
9 | /* | |
10 | * VAX tape boot block for distribution tapes | |
11 | * works on massbys tu78 | |
12 | * | |
13 | * reads a program from a tp directory on a tape and executes it | |
14 | * program must be stripped of the header and is loaded ``bits as is'' | |
15 | * you can return to this loader via ``ret'' as you are called ``calls $0,ent'' | |
16 | * | |
17 | * Based on similar driver for tm03 formatter. | |
18 | * Local modifications by Jeffrey R. Schwab June, 1982 | |
19 | * Purdue University Computing Center | |
20 | */ | |
21 | .set RELOC,0x70000 | |
22 | /* a.out defines */ | |
23 | .set HDRSIZ,040 /* size of file header for VAX */ | |
24 | .set MAGIC,0410 /* file type id in header */ | |
25 | .set TSIZ,4 /* text size */ | |
26 | .set DSIZ,8 /* data size */ | |
27 | .set BSIZ,12 /* bss size */ | |
28 | .set TENT,024 /* task header entry loc */ | |
29 | /* tp directory definitions */ | |
30 | .set FILSIZ,38 /* tp direc offset for file size */ | |
31 | .set BNUM,44 /* tp dir offset for start block no. */ | |
32 | .set ENTSIZ,64 /* size of 1 TP dir entry, bytes */ | |
33 | .set PTHSIZ,32 /* size of TP path name, bytes */ | |
34 | .set BLKSIZ,512 /* tape block size, bytes */ | |
35 | .set NUMDIR,24 /* no. of dir blocks on tape */ | |
36 | .set ENTBLK,8 /* no. of dir entries per tape block */ | |
37 | /* processor registers and bits */ | |
38 | .set RXCS,32 | |
39 | .set RXDB,33 | |
40 | .set TXCS,34 | |
41 | .set TXDB,35 | |
42 | .set RXCS_DONE,0x80 | |
43 | .set TXCS_RDY,0x80 | |
44 | .set TXCS_pr,7 /* bit position of TXCS ready bit */ | |
45 | .set RXCS_pd,7 /* bit position of RXCS done bit */ | |
46 | /* MBA registers */ | |
47 | .set MBA_CSR,0 /* configuration and status register */ | |
48 | .set MBA_CR,4 /* MBA control reg */ | |
49 | .set MBA_SR,8 /* MBA status reg */ | |
50 | .set MBA_VAR,12 /* MBA virt addr reg */ | |
51 | .set MBA_BCR,16 /* MBA byte count reg */ | |
52 | .set MBA_MAP,0x800 /* start of MBA map reg's */ | |
53 | .set MRV,0x80000000 | |
54 | .set MBA_bsy,31 /* massbus busy */ | |
55 | /* TU78 mba registers */ | |
56 | .set MTCS,0 /* MT data transfer control reg */ | |
57 | .set MTER,4 /* data transfer error status reg */ | |
58 | .set MTRC,8 /* record count */ | |
59 | .set MTAS,16 /* attention summary */ | |
60 | .set MTBC,20 /* byte count */ | |
61 | .set MTNER,44 /* non data transfer error status reg */ | |
62 | .set MTNCS,48 /* non data transfer control reg */ | |
63 | .set MTID,68 /* internal data reg */ | |
64 | /* MT commands */ | |
65 | .set GO,1 /* GO bit */ | |
66 | .set MT_REW,6 /* rewind, on-line */ | |
67 | .set MT_RCOM,070 /* read forward */ | |
68 | /* MT bits */ | |
69 | .set MT_rdy,15 /* controller ready */ | |
70 | .set MT_rec,2 /* bit for single record count */ | |
71 | .set MT_rcnt,4 /* record count for single record (shifted) */ | |
72 | .set MT_erc,0xffffffc0 /* error code mask */ | |
73 | .set MT_done,1 /* proper completion code */ | |
735b8f44 SL |
74 | /* local stack variables */ |
75 | .set tapa,-4 /* desired tape addr */ | |
76 | .set mtapa,-8 /* current tape addr */ | |
77 | .set name,-8-PTHSIZ /* operator-typed file name */ | |
78 | /* register usage */ | |
79 | .set rMBA,r10 | |
80 | .set rMT,r11 | |
81 | ||
82 | /* initialization */ | |
83 | init: | |
84 | mull2 $0x80,%rMT | |
85 | addl2 $0x400,%rMT | |
86 | addl2 %rMBA,%rMT | |
87 | movl $RELOC,fp /* core loc to which to move this program */ | |
88 | addl3 $name,fp,sp /* set stack pointer, leaving room for locals */ | |
89 | clrl r0 | |
90 | 1: | |
91 | movc3 $end,(r0),(fp) /* move boot up to relocated position */ | |
92 | jmp start+RELOC | |
93 | start: | |
94 | movl $1,MBA_CR(%rMBA) /* MBA init */ | |
95 | 1: | |
96 | movl MTID(%rMT),r2 /* wait for tape controller to ready */ | |
97 | bbc $MT_rdy,r2,1b /* after massbus init */ | |
98 | bsbw rew /* rewind input tape */ | |
99 | movab name(fp),r4 /* start of filename storage */ | |
100 | movzbl $'=,r0 /* prompt character */ | |
101 | bsbw putc /* output char to main console */ | |
102 | /* read in a file name */ | |
103 | movl r4,r1 /* loc at which to store file name */ | |
104 | nxtc: | |
105 | bsbw getc /* get input char's in file name */ | |
106 | cmpb r0,$012 /* terminator ? */ | |
107 | beql nullc | |
108 | movb r0,(r1)+ | |
109 | brb nxtc | |
110 | nullc: | |
111 | subl3 r4,r1,r9 /* size of path name */ | |
112 | beql start /* dumb operator */ | |
113 | clrb (r1)+ | |
114 | incl r9 | |
115 | /* user-specified TP filename has been stored at name(fp) */ | |
116 | /* read in entire tp directory contents into low core */ | |
117 | dirred: | |
118 | movl $8,tapa(fp) /* tp directory starts at block 8 */ | |
119 | movl $(NUMDIR*BLKSIZ),r6 /* no. bytes in total dir */ | |
120 | bsbw taper /* read no. bytes indicated */ | |
121 | /* search entire directory for user-specified file name */ | |
122 | clrl r5 /* dir buff loc = 0 */ | |
123 | nxtdir: | |
124 | cmpc3 r9,(r5),(r4) /* see if dir entry matches filename */ | |
125 | beql fndfil /* found match */ | |
126 | acbl $NUMDIR*BLKSIZ-1,$ENTSIZ,r5,nxtdir | |
127 | /* see if done with tp dir */ | |
128 | brw start /* entry not in directory; start over */ | |
129 | /* found desired tp dir entry */ | |
130 | fndfil: | |
131 | movzwl BNUM(r5),tapa(fp) /* start block no., 2 bytes */ | |
132 | addl2 $7,tapa(fp) /* skip 7 boot blocks */ | |
133 | movzwl FILSIZ(r5),r6 /* low 2 bytes file size */ | |
134 | insv FILSIZ-1(r5),$16,$8,r6 /* file size, high byte */ | |
135 | cmpl r6,$RELOC-512 /* check if file fits below stack */ | |
136 | blss filok /* file o.k. */ | |
137 | brw start /* file too large */ | |
138 | /* time to read in desired file from tape */ | |
139 | filok: | |
140 | movl r6,r7 /* save r6 */ | |
141 | bsbb taper | |
142 | bsbw rew | |
143 | /* clear core */ | |
144 | subl3 r7,$RELOC-4,r0 /* no. bytes to clear */ | |
145 | 1: | |
146 | clrb (r7)+ | |
147 | sobgtr r0,1b | |
148 | /* time to jump to start of file & execute */ | |
149 | addl3 $20,fp,ap | |
150 | clrl r5 | |
151 | calls $0,(r5) | |
152 | brw start | |
153 | /* taper: movcTAPE (r6),tapa(fp),0 */ | |
154 | rew2: | |
155 | bsbb rew /* beginning of tape */ | |
156 | taper0: | |
157 | bsbb rrec /* advance 1 block; never want blk0 */ | |
158 | taper: | |
159 | clrl r0 /* page no. */ | |
160 | cmpl mtapa(fp),tapa(fp) /* current position .vs. desired */ | |
161 | bgtr rew2 | |
162 | blss taper0 | |
163 | 1: | |
164 | bsbb rrec | |
165 | acbl $1,$-BLKSIZ,r6,1b | |
166 | rsb | |
167 | /* rew: rewind the tape */ | |
168 | rew: | |
169 | clrl mtapa(fp) /* current position */ | |
170 | movl MTNER(%rMT),r2 /* read non-data status */ | |
171 | movl MTAS(%rMT),MTAS(%rMT) /* and clear any attention bits */ | |
172 | movl $MT_REW+GO,MTNCS(%rMT) /* rewind command and go bit */ | |
173 | 1: | |
174 | movl MTAS(%rMT),r2 /* check attention bits */ | |
8e1eb75f | 175 | beql 1b /* loop if attention not yet set */ |
735b8f44 SL |
176 | movl MTNER(%rMT),r2 /* read non-data status */ |
177 | movl MTAS(%rMT),MTAS(%rMT) /* and clear any attention bits */ | |
178 | bicl2 $MT_erc,r2 /* isolate error condition */ | |
179 | subl2 $MT_done,r2 /* check with completion condition */ | |
180 | bneq 1b /* wait for completion attention */ | |
181 | rsb | |
182 | /* rrec: read 1 block from mag tape into page (r0) */ | |
183 | rrec: | |
184 | /* pushl r0; movzbl $'r,r0; bsbw putc; movl (sp)+,r0; */ | |
185 | movl MTNER(%rMT),r2 /* read non-data status */ | |
186 | movl MTAS(%rMT),MTAS(%rMT) /* and clear any attention bits */ | |
187 | movl $-BLKSIZ,MBA_BCR(%rMBA) | |
188 | bisl3 $MRV,r0,MBA_MAP(%rMBA) | |
189 | clrl MBA_VAR(%rMBA) | |
190 | movl $BLKSIZ,MTBC(%rMT) /* set byte count */ | |
191 | bisl2 $MT_rcnt,MTRC(%rMT) /* set record count */ | |
192 | movl $MT_RCOM+GO,MTCS(%rMT) /* load read command */ | |
193 | 1: | |
194 | movl MBA_SR(%rMBA),r2 /* load mba status reg */ | |
195 | bbs $MBA_bsy,r2,1b /* wait for mba to go non-busy */ | |
196 | movl MTRC(%rMT),r2 /* fetch record count */ | |
197 | bbs $MT_rec,r2,rrec /* retry read if we did not read a record */ | |
198 | movl MTER(%rMT),r2 /* load data transfer error status */ | |
199 | bicl2 $MT_erc,r2 /* isolate status value */ | |
200 | subl2 $MT_done,r2 /* compare with successful read */ | |
201 | bneq rrec /* load to try read again */ | |
202 | ||
203 | incl r0 /* next page no. */ | |
204 | incl mtapa(fp) /* mag tape block position */ | |
205 | rsb | |
206 | getc: | |
207 | mfpr $RXCS,r0 | |
208 | bbc $RXCS_pd,r0,getc /* receiver ready ? */ | |
209 | mfpr $RXDB,r0 | |
210 | extzv $0,$7,r0,r0 | |
211 | cmpb r0,$015 | |
212 | bneq putc | |
213 | bsbb putc | |
214 | movb $0,r0 | |
215 | bsbb putc | |
216 | movb $012,r0 | |
217 | putc: | |
218 | mfpr $TXCS,r2 | |
219 | bbc $TXCS_pr,r2,putc /* transmitter ready ? */ | |
220 | extzv $0,$7,r0,r0 | |
221 | mtpr r0,$TXDB | |
222 | rsb | |
223 | end: |