1: MAJOR = 10.                     / major # from bdevsw[]
   2: 
   3: / RP04/05/06 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: / 930124 Fixed major bug that made booting impossible.
  20: /        Lasse Ylitalo & Johnny Billquist
  21: 
  22: / constants:
  23: CLSIZE  = 2.                    / physical disk blocks per logical block
  24: CLSHFT  = 1.                    / shift to multiply by CLSIZE
  25: BSIZE   = 512.*CLSIZE           / logical block size
  26: INOSIZ  = 64.                   / size of inode in bytes
  27: NDIRIN  = 4.                    / number of direct inode addresses
  28: ADDROFF = 12.                   / offset of first address in inode
  29: INOPB   = BSIZE\/INOSIZ         / inodes per logical block
  30: INOFF   = 31.                   / inode offset = (INOPB * (SUPERB+1)) - 1
  31: PBSHFT  = -4                    / shift to divide by inodes per block
  32: WC      = -256.*CLSIZE          / word count
  33: 
  34: /  The boot options and device are placed in the last SZFLAGS bytes
  35: /  at the end of core by the kernel for autobooting.
  36: ENDCORE=        160000          / end of core, mem. management off
  37: SZFLAGS=        6               / size of boot flags
  38: BOOTOPTS=       2               / location of options, bytes below ENDCORE
  39: BOOTDEV=        4
  40: CHECKWORD=      6
  41: 
  42: .. = ENDCORE-512.-SZFLAGS       / save room for boot flags
  43: 
  44: / entry is made by jsr pc,*$0
  45: / so return can be rts pc
  46: 
  47: / establish sp, copy
  48: / program up to end of core.
  49: 
  50:         nop                     / These two lines must be present or DEC
  51:         br      start           / boot ROMs will refuse to run boot block!
  52: start:
  53:         mov     r0,unit
  54:         mov     r1,csr
  55:         mov     $..,sp
  56:         mov     sp,r1
  57:         clr     r0
  58: 1:
  59:         mov     (r0)+,(r1)+
  60:         cmp     r1,$end
  61:         blo     1b
  62:         jmp     *$2f
  63: 
  64: / On error, restart from here.
  65: restart:
  66:         clr     r0
  67: / clear core to make things clean
  68: 2:
  69:         clr     (r0)+
  70:         cmp     r0,sp
  71:         blo     2b
  72: 
  73: / initialize hp
  74:         mov     csr,r1
  75:         mov     unit,hpcs2(r1)
  76:         mov     $preset+go,hpcs1(r1)
  77:         mov     $fmt22,hpof(r1)
  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:         mov     unit,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: read    = 70
 210: preset  = 20
 211: go      = 1
 212: fmt22   = 10000
 213: 
 214: hpcs1   = 0
 215: hpda    = hpcs1+6
 216: hpcs2   = hpcs1+10
 217: hpds    = hpcs1+12
 218: hpof    = hpcs1+32
 219: hpca    = hpcs1+34
 220: 
 221: / rp0456 disk driver.
 222: / low order address in dno,
 223: / high order in r0.
 224: rblk:
 225:         mov     r1,-(sp)
 226:         mov     dno,r1
 227: .if     CLSIZE-1
 228:         ashc    $CLSHFT,r0              / multiply by CLSIZE
 229: .endif
 230:         div     $22.*19.,r0
 231:         mov     csr,r3
 232:         mov     r0,hpca(r3)
 233:         clr     r0
 234:         div     $22.,r0
 235:         swab    r0
 236:         bis     r1,r0
 237:         add     $hpcs2,r3       / 930124 LY&JB
 238:         mov     unit,(r3)
 239:         mov     r0,-(r3)
 240:         mov     $buf,-(r3)
 241:         mov     $WC,-(r3)
 242:         mov     $read+go,-(r3)
 243: 1:
 244:         tstb    (r3)
 245:         bge     1b
 246:         mov     (sp)+,r1
 247:         rts     pc
 248: 
 249: bootnm: <boot\0\0>
 250: bootlen = 4                     / strlen(bootnm)
 251: unit: 0
 252: csr: 0
 253: end:
 254: 
 255: inod = ..-512.-BSIZE            / room for inod, buf, stack
 256: addr = inod+ADDROFF             / first address in inod
 257: buf = inod+INOSIZ
 258: bno = buf+BSIZE
 259: dno = bno+2

Defined functions

ADDROFF defined in line 28; used 1 times
BOOTDEV defined in line 39; never used
BOOTOPTS defined in line 38; used 1 times
BSIZE defined in line 25; used 5 times
CHECKWORD defined in line 40; used 1 times
CLSHFT defined in line 24; used 1 times
CLSIZE defined in line 23; used 3 times
ENDCORE defined in line 36; used 3 times
INOFF defined in line 30; used 1 times
INOPB defined in line 29; never used
INOSIZ defined in line 26; used 3 times
MAJOR defined in line 1; used 1 times
NDIRIN defined in line 27; used 3 times
PBSHFT defined in line 31; used 1 times
SZFLAGS defined in line 37; used 1 times
  • in line 42
WC defined in line 32; used 1 times
addr defined in line 256; used 2 times
again defined in line 83; used 2 times
bno defined in line 258; used 5 times
bootlen defined in line 250; used 1 times
  • in line 87
bootnm defined in line 249; used 1 times
  • in line 79
buf defined in line 257; used 9 times
csr defined in line 252; used 4 times
dno defined in line 259; used 6 times
end defined in line 253; used 1 times
  • in line 60
err defined in line 132; used 1 times
fmt22 defined in line 212; used 1 times
  • in line 77
go defined in line 211; used 2 times
hpca defined in line 219; used 1 times
hpcs1 defined in line 214; used 6 times
hpcs2 defined in line 216; used 2 times
hpda defined in line 215; never used
hpds defined in line 217; never used
hpof defined in line 218; used 1 times
  • in line 77
iget defined in line 101; used 2 times
inod defined in line 255; used 3 times
loadfile defined in line 136; used 1 times
  • in line 98
preset defined in line 210; used 1 times
  • in line 76
rblk defined in line 224; used 4 times
read defined in line 209; used 1 times
readdir defined in line 119; used 2 times
restart defined in line 65; used 2 times
rmblk defined in line 179; used 2 times
start defined in line 52; used 1 times
  • in line 51
unit defined in line 251; used 4 times
Last modified: 1995-06-01
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