123145Smckusick /* 2*29323Smckusick * Copyright (c) 1980, 1986 Regents of the University of California. 323145Smckusick * All rights reserved. The Berkeley software License Agreement 423145Smckusick * specifies the terms and conditions for redistribution. 523145Smckusick */ 611092Ssam 7*29323Smckusick /* "@(#)mtboot.c 7.1 (Berkeley) 06/05/86" */ 823145Smckusick 911092Ssam /* 1011092Ssam * VAX tape boot block for distribution tapes 1111092Ssam * works on massbys tu78 1211092Ssam * 1311092Ssam * reads a program from a tp directory on a tape and executes it 1411092Ssam * program must be stripped of the header and is loaded ``bits as is'' 1511092Ssam * you can return to this loader via ``ret'' as you are called ``calls $0,ent'' 1611092Ssam * 1711092Ssam * Based on similar driver for tm03 formatter. 1811092Ssam * Local modifications by Jeffrey R. Schwab June, 1982 1911092Ssam * Purdue University Computing Center 2011092Ssam */ 2111092Ssam .set RELOC,0x70000 2211092Ssam /* a.out defines */ 2311092Ssam .set HDRSIZ,040 /* size of file header for VAX */ 2411092Ssam .set MAGIC,0410 /* file type id in header */ 2511092Ssam .set TSIZ,4 /* text size */ 2611092Ssam .set DSIZ,8 /* data size */ 2711092Ssam .set BSIZ,12 /* bss size */ 2811092Ssam .set TENT,024 /* task header entry loc */ 2911092Ssam /* tp directory definitions */ 3011092Ssam .set FILSIZ,38 /* tp direc offset for file size */ 3111092Ssam .set BNUM,44 /* tp dir offset for start block no. */ 3211092Ssam .set ENTSIZ,64 /* size of 1 TP dir entry, bytes */ 3311092Ssam .set PTHSIZ,32 /* size of TP path name, bytes */ 3411092Ssam .set BLKSIZ,512 /* tape block size, bytes */ 3511092Ssam .set NUMDIR,24 /* no. of dir blocks on tape */ 3611092Ssam .set ENTBLK,8 /* no. of dir entries per tape block */ 3711092Ssam /* processor registers and bits */ 3811092Ssam .set RXCS,32 3911092Ssam .set RXDB,33 4011092Ssam .set TXCS,34 4111092Ssam .set TXDB,35 4211092Ssam .set RXCS_DONE,0x80 4311092Ssam .set TXCS_RDY,0x80 4411092Ssam .set TXCS_pr,7 /* bit position of TXCS ready bit */ 4511092Ssam .set RXCS_pd,7 /* bit position of RXCS done bit */ 4611092Ssam /* MBA registers */ 4711092Ssam .set MBA_CSR,0 /* configuration and status register */ 4811092Ssam .set MBA_CR,4 /* MBA control reg */ 4911092Ssam .set MBA_SR,8 /* MBA status reg */ 5011092Ssam .set MBA_VAR,12 /* MBA virt addr reg */ 5111092Ssam .set MBA_BCR,16 /* MBA byte count reg */ 5211092Ssam .set MBA_MAP,0x800 /* start of MBA map reg's */ 5311092Ssam .set MRV,0x80000000 5411092Ssam .set MBA_bsy,31 /* massbus busy */ 5511092Ssam /* TU78 mba registers */ 5611092Ssam .set MTCS,0 /* MT data transfer control reg */ 5711092Ssam .set MTER,4 /* data transfer error status reg */ 5811092Ssam .set MTRC,8 /* record count */ 5911092Ssam .set MTAS,16 /* attention summary */ 6011092Ssam .set MTBC,20 /* byte count */ 6111092Ssam .set MTNER,44 /* non data transfer error status reg */ 6211092Ssam .set MTNCS,48 /* non data transfer control reg */ 6311092Ssam .set MTID,68 /* internal data reg */ 6411092Ssam /* MT commands */ 6511092Ssam .set GO,1 /* GO bit */ 6611092Ssam .set MT_REW,6 /* rewind, on-line */ 6711092Ssam .set MT_RCOM,070 /* read forward */ 6811092Ssam /* MT bits */ 6911092Ssam .set MT_rdy,15 /* controller ready */ 7011092Ssam .set MT_rec,2 /* bit for single record count */ 7111092Ssam .set MT_rcnt,4 /* record count for single record (shifted) */ 7211092Ssam .set MT_erc,0xffffffc0 /* error code mask */ 7311092Ssam .set MT_done,1 /* proper completion code */ 7411092Ssam /* local stack variables */ 7511092Ssam .set tapa,-4 /* desired tape addr */ 7611092Ssam .set mtapa,-8 /* current tape addr */ 7711092Ssam .set name,-8-PTHSIZ /* operator-typed file name */ 7811092Ssam /* register usage */ 7911092Ssam .set rMBA,r10 8011092Ssam .set rMT,r11 8111092Ssam 8211092Ssam /* initialization */ 8311092Ssam init: 8411092Ssam mull2 $0x80,%rMT 8511092Ssam addl2 $0x400,%rMT 8611092Ssam addl2 %rMBA,%rMT 8711092Ssam movl $RELOC,fp /* core loc to which to move this program */ 8811092Ssam addl3 $name,fp,sp /* set stack pointer, leaving room for locals */ 8911092Ssam clrl r0 9011092Ssam 1: 9111092Ssam movc3 $end,(r0),(fp) /* move boot up to relocated position */ 9211092Ssam jmp start+RELOC 9311092Ssam start: 9411092Ssam movl $1,MBA_CR(%rMBA) /* MBA init */ 9511092Ssam 1: 9611092Ssam movl MTID(%rMT),r2 /* wait for tape controller to ready */ 9711092Ssam bbc $MT_rdy,r2,1b /* after massbus init */ 9811092Ssam bsbw rew /* rewind input tape */ 9911092Ssam movab name(fp),r4 /* start of filename storage */ 10011092Ssam movzbl $'=,r0 /* prompt character */ 10111092Ssam bsbw putc /* output char to main console */ 10211092Ssam /* read in a file name */ 10311092Ssam movl r4,r1 /* loc at which to store file name */ 10411092Ssam nxtc: 10511092Ssam bsbw getc /* get input char's in file name */ 10611092Ssam cmpb r0,$012 /* terminator ? */ 10711092Ssam beql nullc 10811092Ssam movb r0,(r1)+ 10911092Ssam brb nxtc 11011092Ssam nullc: 11111092Ssam subl3 r4,r1,r9 /* size of path name */ 11211092Ssam beql start /* dumb operator */ 11311092Ssam clrb (r1)+ 11411092Ssam incl r9 11511092Ssam /* user-specified TP filename has been stored at name(fp) */ 11611092Ssam /* read in entire tp directory contents into low core */ 11711092Ssam dirred: 11811092Ssam movl $8,tapa(fp) /* tp directory starts at block 8 */ 11911092Ssam movl $(NUMDIR*BLKSIZ),r6 /* no. bytes in total dir */ 12011092Ssam bsbw taper /* read no. bytes indicated */ 12111092Ssam /* search entire directory for user-specified file name */ 12211092Ssam clrl r5 /* dir buff loc = 0 */ 12311092Ssam nxtdir: 12411092Ssam cmpc3 r9,(r5),(r4) /* see if dir entry matches filename */ 12511092Ssam beql fndfil /* found match */ 12611092Ssam acbl $NUMDIR*BLKSIZ-1,$ENTSIZ,r5,nxtdir 12711092Ssam /* see if done with tp dir */ 12811092Ssam brw start /* entry not in directory; start over */ 12911092Ssam /* found desired tp dir entry */ 13011092Ssam fndfil: 13111092Ssam movzwl BNUM(r5),tapa(fp) /* start block no., 2 bytes */ 13211092Ssam addl2 $7,tapa(fp) /* skip 7 boot blocks */ 13311092Ssam movzwl FILSIZ(r5),r6 /* low 2 bytes file size */ 13411092Ssam insv FILSIZ-1(r5),$16,$8,r6 /* file size, high byte */ 13511092Ssam cmpl r6,$RELOC-512 /* check if file fits below stack */ 13611092Ssam blss filok /* file o.k. */ 13711092Ssam brw start /* file too large */ 13811092Ssam /* time to read in desired file from tape */ 13911092Ssam filok: 14011092Ssam movl r6,r7 /* save r6 */ 14111092Ssam bsbb taper 14211092Ssam bsbw rew 14311092Ssam /* clear core */ 14411092Ssam subl3 r7,$RELOC-4,r0 /* no. bytes to clear */ 14511092Ssam 1: 14611092Ssam clrb (r7)+ 14711092Ssam sobgtr r0,1b 14811092Ssam /* time to jump to start of file & execute */ 14911092Ssam addl3 $20,fp,ap 15011092Ssam clrl r5 15111092Ssam calls $0,(r5) 15211092Ssam brw start 15311092Ssam /* taper: movcTAPE (r6),tapa(fp),0 */ 15411092Ssam rew2: 15511092Ssam bsbb rew /* beginning of tape */ 15611092Ssam taper0: 15711092Ssam bsbb rrec /* advance 1 block; never want blk0 */ 15811092Ssam taper: 15911092Ssam clrl r0 /* page no. */ 16011092Ssam cmpl mtapa(fp),tapa(fp) /* current position .vs. desired */ 16111092Ssam bgtr rew2 16211092Ssam blss taper0 16311092Ssam 1: 16411092Ssam bsbb rrec 16511092Ssam acbl $1,$-BLKSIZ,r6,1b 16611092Ssam rsb 16711092Ssam /* rew: rewind the tape */ 16811092Ssam rew: 16911092Ssam clrl mtapa(fp) /* current position */ 17011092Ssam movl MTNER(%rMT),r2 /* read non-data status */ 17111092Ssam movl MTAS(%rMT),MTAS(%rMT) /* and clear any attention bits */ 17211092Ssam movl $MT_REW+GO,MTNCS(%rMT) /* rewind command and go bit */ 17311092Ssam 1: 17411092Ssam movl MTAS(%rMT),r2 /* check attention bits */ 17513199Sroot beql 1b /* loop if attention not yet set */ 17611092Ssam movl MTNER(%rMT),r2 /* read non-data status */ 17711092Ssam movl MTAS(%rMT),MTAS(%rMT) /* and clear any attention bits */ 17811092Ssam bicl2 $MT_erc,r2 /* isolate error condition */ 17911092Ssam subl2 $MT_done,r2 /* check with completion condition */ 18011092Ssam bneq 1b /* wait for completion attention */ 18111092Ssam rsb 18211092Ssam /* rrec: read 1 block from mag tape into page (r0) */ 18311092Ssam rrec: 18411092Ssam /* pushl r0; movzbl $'r,r0; bsbw putc; movl (sp)+,r0; */ 18511092Ssam movl MTNER(%rMT),r2 /* read non-data status */ 18611092Ssam movl MTAS(%rMT),MTAS(%rMT) /* and clear any attention bits */ 18711092Ssam movl $-BLKSIZ,MBA_BCR(%rMBA) 18811092Ssam bisl3 $MRV,r0,MBA_MAP(%rMBA) 18911092Ssam clrl MBA_VAR(%rMBA) 19011092Ssam movl $BLKSIZ,MTBC(%rMT) /* set byte count */ 19111092Ssam bisl2 $MT_rcnt,MTRC(%rMT) /* set record count */ 19211092Ssam movl $MT_RCOM+GO,MTCS(%rMT) /* load read command */ 19311092Ssam 1: 19411092Ssam movl MBA_SR(%rMBA),r2 /* load mba status reg */ 19511092Ssam bbs $MBA_bsy,r2,1b /* wait for mba to go non-busy */ 19611092Ssam movl MTRC(%rMT),r2 /* fetch record count */ 19711092Ssam bbs $MT_rec,r2,rrec /* retry read if we did not read a record */ 19811092Ssam movl MTER(%rMT),r2 /* load data transfer error status */ 19911092Ssam bicl2 $MT_erc,r2 /* isolate status value */ 20011092Ssam subl2 $MT_done,r2 /* compare with successful read */ 20111092Ssam bneq rrec /* load to try read again */ 20211092Ssam 20311092Ssam incl r0 /* next page no. */ 20411092Ssam incl mtapa(fp) /* mag tape block position */ 20511092Ssam rsb 20611092Ssam getc: 20711092Ssam mfpr $RXCS,r0 20811092Ssam bbc $RXCS_pd,r0,getc /* receiver ready ? */ 20911092Ssam mfpr $RXDB,r0 21011092Ssam extzv $0,$7,r0,r0 21111092Ssam cmpb r0,$015 21211092Ssam bneq putc 21311092Ssam bsbb putc 21411092Ssam movb $0,r0 21511092Ssam bsbb putc 21611092Ssam movb $012,r0 21711092Ssam putc: 21811092Ssam mfpr $TXCS,r2 21911092Ssam bbc $TXCS_pr,r2,putc /* transmitter ready ? */ 22011092Ssam extzv $0,$7,r0,r0 22111092Ssam mtpr r0,$TXDB 22211092Ssam rsb 22311092Ssam end: 224