1: MAJOR = 7                       / major # from bdevsw[]
   2: 
   3: / RL01/02 bootstrap.
   4: /
   5: / 1995/05/31 - The unit number needs to go in bits 3-5 of bootdev
   6: /	       because the partition number now goes into bits 0-2.
   7: /
   8: / disk boot program to load and transfer
   9: / to a unix entry.
  10: / for use with 1 KB byte blocks, CLSIZE is 2.
  11: / NDIRIN is the number of direct inode addresses (currently 4)
  12: / assembled size must be <= 512; if > 494, the 16-byte a.out header
  13: / must be removed
  14: 
  15: / options: none.  all options of reading an alternate name or echoing to
  16: /		  the keyboard had to be removed to make room for the
  17: /		  code which understands the new directory structure on disc
  18: 
  19: / constants:
  20: CLSIZE  = 2.                    / physical disk blocks per logical block
  21: CLSHFT  = 1.                    / shift to multiply by CLSIZE
  22: BSIZE   = 512.*CLSIZE           / logical block size
  23: INOSIZ  = 64.                   / size of inode in bytes
  24: NDIRIN  = 4.                    / number of direct inode addresses
  25: ADDROFF = 12.                   / offset of first address in inode
  26: INOPB   = BSIZE\/INOSIZ         / inodes per logical block
  27: INOFF   = 31.                   / inode offset = (INOPB * (SUPERB+1)) - 1
  28: PBSHFT  = -4                    / shift to divide by inodes per block
  29: WC      = -256.*CLSIZE          / word count
  30: 
  31: /  The boot options and device are placed in the last SZFLAGS bytes
  32: /  at the end of core by the kernel for autobooting.
  33: ENDCORE=        160000          / end of core, mem. management off
  34: SZFLAGS=        6               / size of boot flags
  35: BOOTOPTS=       2               / location of options, bytes below ENDCORE
  36: BOOTDEV=        4
  37: CHECKWORD=      6
  38: 
  39: .. = ENDCORE-512.-SZFLAGS       / save room for boot flags
  40: 
  41: / entry is made by jsr pc,*$0
  42: / so return can be rts pc
  43: 
  44:         nop                     / These two lines must be present or DEC MXV-11
  45:         br      start           / boot ROMs will refuse to run boot block!
  46: 
  47: / establish sp, copy
  48: / program up to end of core.
  49: start:
  50:         movb    r0,unit+1       / unit # in high byte
  51:         mov     r1,csr
  52:         mov     $..,sp
  53:         mov     sp,r1
  54:         clr     r0
  55: 1:
  56:         mov     (r0)+,(r1)+
  57:         cmp     r1,$end
  58:         blo     1b
  59:         jmp     *$2f
  60: 
  61: / On error, restart from here.
  62: restart:
  63:         clr     r0
  64: / clear core to make things clean
  65: 2:
  66:         clr     (r0)+
  67:         cmp     r0,sp
  68:         blo     2b
  69: 
  70: / initialize rl
  71: 
  72: /	mov	$13,*$rlda	/get status
  73: /	mov	$4,*$rlcs
  74: /
  75: /	jsr pc,rdy
  76: /	mov *$rlda,r5	/superstision
  77: /
  78: 
  79:         mov     $bootnm, r1
  80:         mov     $2,r0                   / ROOTINO
  81:         jsr     pc,iget
  82:         clr     r2                      / offset
  83: again:
  84:         jsr     pc,readdir
  85:         beq     restart                 / error - restart
  86:         mov     4(r0),r4                / dp->d_namlen
  87:         cmp     r4,$bootlen             / if (bootlen == dp->d_namlen)
  88:         bne     again                   /    nope, go try next entry
  89:         mov     r0,r3
  90:         add     $6,r3                   / r3 = dp->d_name
  91:         mov     r1,r5                   / r5 = filename
  92: 9:
  93:         cmpb    (r3)+,(r5)+
  94:         bne     again                   / no match - go read next entry
  95:         sob     r4,9b
  96:         mov     (r0),r0                 / r0 = dp->d_ino
  97:         jsr     pc,iget                 / fetch boot's inode
  98:         br      loadfile                / 'boot'- go read it
  99: 
 100: / get the inode specified in r0
 101: iget:
 102:         add     $INOFF,r0
 103:         mov     r0,r5
 104:         ash     $PBSHFT,r0
 105:         bic     $!7777,r0
 106:         mov     r0,dno
 107:         clr     r0
 108:         jsr     pc,rblk
 109:         bic     $!17,r5
 110:         mov     $INOSIZ,r0
 111:         mul     r0,r5
 112:         add     $buf,r5
 113:         mov     $inod,r4
 114: 1:
 115:         movb    (r5)+,(r4)+
 116:         sob     r0,1b
 117:         rts     pc
 118: 
 119: readdir:
 120:         bit     $BSIZE-1,r2
 121:         bne     1f
 122:         jsr     pc,rmblk                / read mapped block (bno)
 123:                 br err                  / end of file branch
 124:         clr     r2                      / start at beginning of buf
 125: 1:
 126:         mov     $buf,r0
 127:         add     r2,r0                   / dp = buf+offset
 128:         add     buf+2(r2),r2            / dp += dp->d_reclen
 129:         tst     (r0)                    / dp->d_ino == 0?
 130:         beq     readdir                 / yes - go look at next
 131:         rts     pc                      / return with r0 = &dp->d_ino
 132: err:
 133:         clr     r0                      / return with
 134:         rts     pc                      / dp = NULL
 135: 
 136: loadfile:
 137:         clr     bno                     / start at block 0 of inode in 'inod'
 138: / read file into core until
 139: / a mapping error, (no disk address)
 140:         clr     r1
 141: 1:
 142:         jsr     pc,rmblk
 143:                 br 1f
 144:         mov     $buf,r2
 145: 2:
 146:         mov     (r2)+,(r1)+
 147:         cmp     r2,$buf+BSIZE
 148:         blo     2b
 149:         br      1b
 150: / relocate core around
 151: / assembler header
 152: 1:
 153:         clr     r0
 154:         cmp     (r0),$407
 155:         bne     2f
 156: 1:
 157:         mov     20(r0),(r0)+
 158:         cmp     r0,sp
 159:         blo     1b
 160: / enter program and
 161: / restart if return
 162: 2:
 163:         mov     ENDCORE-BOOTOPTS, r4
 164:         movb    unit+1,r3
 165:         ash     $3,r3                   / unit # in bits 3-5, partition # is 0
 166:         bis     $MAJOR\<8.,r3
 167:         mov     ENDCORE-CHECKWORD, r2
 168:         mov     csr,r1
 169:         jsr     pc,*$0
 170:         br      restart
 171: 
 172: / read a mapped block
 173: / offset in file is in bno.
 174: / skip if success, no skip if fail
 175: / the algorithm only handles a single
 176: / indirect block. that means that
 177: / files longer than NDIRIN+256 blocks (260kb) cannot
 178: / be loaded.
 179: rmblk:
 180:         add     $2,(sp)
 181:         mov     bno,r0
 182:         cmp     r0,$NDIRIN
 183:         blt     1f
 184:         mov     $NDIRIN,r0
 185: 1:
 186:         ash     $2,r0
 187:         mov     addr+2(r0),dno
 188:         mov     addr(r0),r0
 189:         bne     1f
 190:         tst     dno
 191:         beq     2f
 192: 1:
 193:         jsr     pc,rblk
 194:         mov     bno,r0
 195:         inc     bno
 196:         sub     $NDIRIN,r0
 197:         blt     1f
 198:         ash     $2,r0
 199:         mov     buf+2(r0),dno
 200:         mov     buf(r0),r0
 201:         bne     rblk
 202:         tst     dno
 203:         bne     rblk
 204: 2:
 205:         sub     $2,(sp)
 206: 1:
 207:         rts     pc
 208: 
 209: /
 210: /	RL02 read only non-interrupt driven driver
 211: /	Dave Clemans, TEK, 4/8/82
 212: /
 213: /	NOTE:
 214: /		errors are NOT checked
 215: /		spiral reads are NOT implemented
 216: /		it MUST run in the lower 64K address space
 217: /
 218: /	Parameters:
 219: /		r0: high part of disk block number
 220: /		dno: low part of disk block number
 221: /		WC: amount of data to read
 222: /		buf: buffer to read data into
 223: /
 224: /	Register usage:
 225: /		r1,r2: used, but saved
 226: /		r0,r3,r4 used and clobbered
 227: rlcs    = 0             / offset from base csr
 228: rlba    = 2
 229: rlda    = 4
 230: rlmp    = 6
 231: 
 232: READ    = 14
 233: SEEK    = 6
 234: RDHDR   = 10
 235: SEEKHI  = 5
 236: SEEKLO  = 1
 237: CRDY    = 200
 238: RLSECT  = 20.
 239: 
 240: rblk:
 241:         mov     r1,-(sp)
 242:         mov     r2,-(sp)
 243:         mov     csr,r4
 244:         mov     dno,r1
 245: .if     CLSIZE-1
 246:         ashc    $CLSHFT,r0      / multiply by CLSIZE
 247: .endif
 248:         div     $RLSECT,r0      / cylinder number - surface
 249:         asl     r1              / sector number
 250:         mov     unit,-(sp)
 251:         bis     $RDHDR,(sp)
 252:         mov     (sp)+,(r4)      / find where the heads are now
 253: 7:      tstb    (r4)            / wait for the STUPID!!! controller (CRDY=200)
 254:         bpl     7b
 255:         mov     rlmp(r4),r2
 256:         ash     $-7,r2
 257:         bic     $!777,r2        / we are at this cylinder now
 258:         mov     r0,r3
 259:         asr     r3              / desired cylinder number
 260:         sub     r3,r2           / compute relative seek distance
 261:         bge     1f              / up or down?
 262:         neg     r2
 263:         ash     $7,r2
 264:         bis     $SEEKHI,r2      / up
 265:         br      2f
 266: 1:      ash     $7,r2
 267:         inc     r2              / down (SEEKLO = 1, so just do 'inc')
 268: 2:      mov     r0,r3           / compute desired disk surface
 269:         bic     $!1,r3
 270:         ash     $4,r3
 271:         bis     r3,r2
 272:         mov     r2,rlda(r4)     / disk address for seek
 273:         mov     unit,-(sp)
 274:         bis     $SEEK,(sp)
 275:         mov     (sp)+,(r4)      / do the seek
 276: 7:      tstb    (r4)            / wait for the STUPID!!! controller
 277:         bpl     7b
 278:         ash     $6,r0           / compute disk address for read
 279:         bis     r1,r0
 280:         add     $rlmp,r4        / point to rlmp
 281:         mov     $WC,(r4)        / word count for read
 282:         mov     r0,-(r4)        / disk address for read
 283:         mov     $buf,-(r4)      / buffer address for read
 284:         mov     unit,-(sp)
 285:         bis     $READ,(sp)
 286:         mov     (sp)+,-(r4)     / do the read
 287: 7:      tstb    (r4)            / wait for the STUPID!!! controller
 288:         bpl     7b
 289:         mov     (sp)+,r2
 290:         mov     (sp)+,r1
 291:         rts     pc
 292: 
 293: bootnm: <boot\0\0>
 294: bootlen = 4                     / strlen(bootnm)
 295: unit: 0
 296: csr: 0
 297: end:
 298: 
 299: inod = ..-512.-BSIZE            / room for inod, buf, stack
 300: addr = inod+ADDROFF             / first address in inod
 301: buf = inod+INOSIZ
 302: bno = buf+BSIZE
 303: dno = bno+2

Defined functions

ADDROFF defined in line 25; used 1 times
BOOTDEV defined in line 36; never used
BOOTOPTS defined in line 35; used 1 times
BSIZE defined in line 22; used 5 times
CHECKWORD defined in line 37; used 1 times
CLSHFT defined in line 21; used 1 times
CLSIZE defined in line 20; used 3 times
CRDY defined in line 237; never used
ENDCORE defined in line 33; used 3 times
INOFF defined in line 27; used 1 times
INOPB defined in line 26; never used
INOSIZ defined in line 23; used 3 times
MAJOR defined in line 1; used 1 times
NDIRIN defined in line 24; used 3 times
PBSHFT defined in line 28; used 1 times
RDHDR defined in line 234; used 1 times
READ defined in line 232; used 1 times
RLSECT defined in line 238; used 1 times
SEEK defined in line 233; used 1 times
SEEKHI defined in line 235; used 1 times
SEEKLO defined in line 236; never used
SZFLAGS defined in line 34; used 1 times
  • in line 39
WC defined in line 29; used 1 times
addr defined in line 300; used 2 times
again defined in line 83; used 2 times
bno defined in line 302; used 5 times
bootlen defined in line 294; used 1 times
  • in line 87
bootnm defined in line 293; used 1 times
  • in line 79
buf defined in line 301; used 9 times
csr defined in line 296; used 3 times
dno defined in line 303; used 6 times
end defined in line 297; used 1 times
  • in line 57
err defined in line 132; used 1 times
iget defined in line 101; used 2 times
inod defined in line 299; used 3 times
loadfile defined in line 136; used 1 times
  • in line 98
rblk defined in line 240; used 4 times
readdir defined in line 119; used 2 times
restart defined in line 62; used 2 times
rlba defined in line 228; never used
rlcs defined in line 227; never used
rlda defined in line 229; used 1 times
rlmp defined in line 230; used 2 times
rmblk defined in line 179; used 2 times
start defined in line 49; used 1 times
  • in line 45
unit defined in line 295; used 5 times
Last modified: 1995-06-01
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