V1/u0.s
/ u0 -- unix
cold = 0
orig = 0 . / orig = 0. relocatable
rkda = 177412 / disk address reg rk03/rk11
rkds = 177400 / driv status reg rk03/rk11
rkcs = 177404 / control status reg rk03/rk11
rcsr = 174000 / receiver status reg dc-11
rcbr = 174002 / receiver buffer reg dc-11
tcsr = 174004 / xmtr status reg dc-11
tcbr = 174006 / xmtr buffer reg dc-11
tcst = 177340 / dec tape control status tc11/tu56
tccm = 177342 / dec tape command reg tc11/tu56
tcwc = 177344 / word count tc11/tu56
tcba = 177346 / bus addr tc11/tu56
tcdt = 177350 / data reg tc11/tu56
dcs = 177460 / drum control status rf11/rs11
dae = 177470 / drum address extension rf11/rs11
lks = 177546 / clock status reg kw11-l
prs = 177550 / papertape reader status pc11
prb = 177552 / buffer pc11
pps = 177554 / punch status pc11
ppb = 177556 / punch buffer pc11
/lps = 177514 line printer status (future)
/lpb = 177516 line printer buffer (future)
tks = 177560 / console read status asr-33
tkb = 177562 / read buffer asr-33
tps = 177564 / punch status asr-33
tpb = 177566 / punch buffer asr-33
ps = 177776 / processor status
halt = 0
wait = 1
rti = 2
nproc = 16. / number of processes
nfiles = 50.
ntty = 8+1
nbuf = 6
.if cold / ignored if cold = 0
nbuf = 2
.endif
core = orig+40000 / specifies beginning of user's core
ecore = core+20000 / specifies end of user's core (4096 words)
/ 4;4 init by copy
/ unkni;0 " error
/ fpsym;0 " illg in tr
unkni;0 / trace and trap (see Sec. B.1 page )
unkni;0 / trap
panic;0 / pwr
rtssym;0 / emt
sysent;0 / sys
. = orig+60
ttyi;240 / interrupt vector tty in ; processor level 5
ttyo;240 / interrupt vector tty out
ppti;240 / punch papertape in
ppto;240 / punch papertape out
clock;340 / clock interrupt vector ; processor level 7
. = orig+200
/ lpto; 240 line printer interrupt ; processor level 5 (future)
. = orig+204
drum;300 / drum interrupt ; processor level 6
. = orig+214
tape;300 / dec tape interrupt
disk;300 / rk03 interrupt
. = orig+300
0*4+trcv; 240; 0*4+txmt; 240 / dc11 input,output interrupt vectors
1*4+trcv; 240; 1*4+txmt; 240
2*4+trcv; 240; 2*4+txmt; 240
3*4+trcv; 240; 3*4+txmt; 240
4*4+trcv; 240; 4*4+txmt; 240
5*4+trcv; 240; 5*4+txmt; 240
6*4+trcv; 240; 6*4+txmt; 240
7*4+trcv; 240; 7*4+txmt; 240
. = orig+400
/ copy in transfer vectors
mov $ecore,sp / put pointer to ecore in the stack pointer
jsr r0,copyz; 0; 14 / clear locations 0 to 14 in core
mov $4,r0
clr r1
mov r0,(r1)+ / put value of 4 into location 0
mov r0,(r1)+ / put value of 4 into location 2
mov $unkni,(r1)+ / put value of unkni into location 4;
/ time out, bus error
clr (r1)+ / put value of 0 into location 6
mov $fpsym,(r1)+ / put value of fpsym into location 10
clr (r1)+ / put value of 0 into location 12
/ clear core
.if cold / ignored if cold = 0
halt / halt before initializing rf file system; user has
/ last chance to reconsider
.endif
jsr r0,copyz; systm; ecore / clear locations systm to ecore
mov $s.chrgt+2,clockp / intialize clockp
/ allocate tty buffers; see H.0 for description
mov $buffer,r0
mov $tty+6,r1
1:
mov r0,(r1)
add $140.,r0 / tty buffers are 140. bytes long
add $8,r1
cmp r1,$tty+[ntty*8] / has a buffer been assigned for each tty
blo 1b
/ allocate disk buffers; see H.0 for description
mov $bufp,r1
1:
mov r0,(r1)+
add $8,r0
mov r0,-2(r0) / bus address
mov $-256.,-4(r0) / word count
add $512.,r0 / buffer space
cmp r1,$bufp+nbuf+nbuf
blo 1b
mov $sb0,(r1)+ / I/O queue entry drum
mov $sb1,(r1)+ / I/O queue entry disk (mounted device)
mov $swp,(r1)+ / I/O queue entry core image being swapped
mov $[systm-inode]\/2,sb0+4 / sets up initial buffers per
/ format given in
mov $systm,sb0+6 / memory map
mov $-512.,sb1+4
mov $mount,sb1+6
mov $user,swp+6
/ set devices to interrupt
mov $100,*$lks / put 100 into clock status register;
/ enables clock interrupt
/ set up time out subroutines
mov $touts,r0
mov $startty,(r0)+ / if toutt = 0 call startty
mov $pptito,(r0)+ / if toutt+1 = 0 call pptito
tst (r0)+ / add 2 to r0
mov $ntty-1,r1
1 :
mov $xmtto,(r0)+ / if toutt+2 thru toutt+2+ntty=0 call xmtto
dec r1
bne 1b
/ free all character blocks; see H.0 for description
mov $510.,r2
mov $-1,r1
1:
jsr r0,put
sub $2,r2
bgt 1b
/ set up drum swap addresses; see H.0 for description
mov $1024.-64.,r1 / highest drum address; high 64 blks allocated
/ to UNIX
mov $p.dska,r2 / p.dska contains dis addresses for processes
1 :
sub $17.,r1 / 17 blocks per process
mov r1,(r2)+
cmp r2,$p.dska+nproc+nproc
bne 1b
/ free rest of drum
.if cold
mov $128.,systm / initialize word 1 of drum superblock image;
/ number of bytes in free storage map=128.
mov $64.,systm+2+128. / init. wd 66. of superblock image; # of
/ bytes in i-node map=64.
1:
dec r1 / r1=687.,...,34.
jsr r0,free / free block 'r1', i.e., set bit 'r1' in free
/ storage map in core
cmp r1,$34. / first drum address not in i list
bgt 1b / if block 34 has been freed, zero i list
/ zero i list
1:
dec r1 / r1=33.,...,1
jsr r0,clear / zero block 'r1' on fixed head disk
tst r1
bgt 1b / if blocks 33,...,1 have all been zeroed, done.
.endif
/ make current program a user
mov $41.,r0 / rootdir set to 41 and never changed
mov r0,rootdir / rootdir is i-number of root directory
mov r0,u.cdir / u.cdir is i-number of process current directory
mov $1,r0
movb r0,u.uno / set process table index for this process to 1
mov r0,mpid / initialize mpid to 1
mov r0,p.pid / p.pid identifies process
movb r0,p.stat / process status = 1 i.e., active
/ = 0 free
.if cold / = 2 waiting for a child to die
/ = 3 terminated but not yet waited
/ for
/ initialize inodes for special files (inodes 1 to 40.)
mov $40.,r1 / set r1=i-node-number 40.
1:
jsr r0,iget / read i-node 'r1' from disk into inode area of
/ core and write modified inode out (if any)
mov $100017,i.flgs / set flags in core image of inode to indi-
/ cate allocated, read (owner, non-owner),
/ write (owner, non-owner)
movb $1,i.nlks / set no. of links = 1
movb $1,i.uid / set user id of owner = 1
jsr r0,setimod / set imod=1 to indicate i-node modified, also
/ stuff time of modification into i-node
dec r1 / next i-node no. = present i-node no.-1
bgt 1b / has i-node 1 been initialized; no, branch
/ initialize i-nodes r1.,...,47. and write the root device, binary, etc.,
/ directories onto fixed head disk. user temporary, initialization prog.
mov $idata,r0 / r0=base addr. of assembled directories.
mov $u.off,u.fofp / pointer to u.off in u.fofp (holds file
/ offset)
1:
mov (r0)+,r1/r1=41.,...,47; "0" in the assembled directory
/ header signals last
beq 1f / assembled directory has been written onto drum
jsr r0,imap / locate the inode map bit for i-node 'r1'
bisb mq,(r2) / set the bit to indicate the i-node is not
/ available
jsr r0,iget / read inode 'r1' from disk into inode area of
/ core and write modified i-node on drum (if any)
mov (r0)+,i.flgs / set flags in core image of inode from
/ assembled directories header
movb (r0)+,i.nlks / set no. of links from header
movb (r0)+,i.uid / set user id of owner from header
jsr r0,setimod / set imod=1 to indicate inode modified; also,
/ stuff time of modification into i-node
mov (r0)+,u.count / set byte count for write call equal to
/ size of directory
mov r0,u.base / set buffer address for write to top of directory
clr u.off / clear file offset used in 'seek' and 'tell'
add u.count,r0 / r0 points to the header of the next directory
jsr r0,writei / write the directory and i-node onto drum
br 1b / do next directory
.endif
/ next 2 instructions not executed during cold boot.
bis $2000,sb0 / sb0 I/O queue entry for superblock on drum;
/ set bit 10 to 1
jsr r0,ppoke / read drum superblock
1:
tstb sb0+1 / has I/O request been honored (for drum)?
bne 1b / no, continue to idle.
1:
decb sysflg / mormally sysflag=0, indicates executing in system
sys exec; 2f; 1f / generates trap interrupt; trap vector =
/ sysent; 0
br panic / execute file/etc/init
1:
2f;0
2:
</etc/init\0> / UNIX looks for strings term, noted by nul\0
panic:
clr ps
1:
dec $0
bne 1b
dec $5
bne 1b
jmp *$173700 / rom loader address
rtssym:
mov r0,-(sp)
mov r1,-(sp)
mov 4(sp),r0
mov -(r0),r0
bic $!7,r0
asl r0
jmp *1f(r0)
1:
0f;1f;2f;3f;4f;5f;badrts;7f
0:
mov 2(sp),r0
br 1f
2:
mov r2,r1
br 1f
3:
mov r3,r1
br 1f
4:
mov r4,r1
br 1f
5:
mov r5,r1
br 1f
7:
mov 8.(sp),r1
1:
cmp r1,$core
blo badrts
cmp r1,$ecore
bhis badrts
bit $1,r1
bne badrts
tst (r1)
beq badrts
add $1f,r0
mov r0,4(sp)
mov (sp)+,r1
mov (sp)+,r0
rti
1:
rts r0
rts r1
rts r2
rts r3
rts r4
rts r5
rts sp
rts pc
badrts:
mov (sp)+,r1
mov (sp)+,r0
rpsym:
jmp unkni
.if cold
idata:
/ root
41.
140016
.byte 7,1
9f-.-2
41.
<..\0\0\0\0\0\0>
41.
<.\0\0\0\0\0\0\0>
42.
<dev\0\0\0\0\0>
43.
<bin\0\0\0\0\0>
44.
<etc\0\0\0\0\0>
45.
<usr\0\0\0\0\0>
46.
<tmp\0\0\0\0\0>
9:
/ device directory
42.
140016
.byte 2,1
9f-.-2
41.
<..\0\0\0\0\0\0>
42.
<.\0\0\0\0\0\0\0>
01.
<tty\0\0\0\0\0>
02.
<ppt\0\0\0\0\0>
03.
<mem\0\0\0\0\0>
04.
<rf0\0\0\0\0\0>
05.
<rk0\0\0\0\0\0>
06.
<tap0\0\0\0\0>
07.
<tap1\0\0\0\0>
08.
<tap2\0\0\0\0>
09.
<tap3\0\0\0\0>
10.
<tap4\0\0\0\0>
11.
<tap5\0\0\0\0>
12.
<tap6\0\0\0\0>
13.
<tap7\0\0\0\0>
14.
<tty0\0\0\0\0>
15.
<tty1\0\0\0\0>
16.
<tty2\0\0\0\0>
17.
<tty3\0\0\0\0>
18.
<tty4\0\0\0\0>
19.
<tty5\0\0\0\0>
20.
<tty6\0\0\0\0>
21.
<tty7\0\0\0\0>
22.
<lpr\0\0\0\0\0>
01.
<tty8\0\0\0\0> / really tty
9:
/ binary directory
43.
140016
.byte 2,3
9f-.-2
41.
<..\0\0\0\0\0\0>
43.
<.\0\0\0\0\0\0\0>
9:
/ etcetra directory
44.
140016
.byte 2,3
9f-.-2
41.
<..\0\0\0\0\0\0>
44.
<.\0\0\0\0\0\0\0>
47.
<init\0\0\0\0>
9:
/ user directory
45.
140016
.byte 2,1
9f-.-2
41.
<..\0\0\0\0\0\0>
45.
<.\0\0\0\0\0\0\0>
9:
/ temporary directory
46.
140017
.byte 2,1
9f-.-2
41.
<..\0\0\0\0\0\0>
46.
<.\0\0\0\0\0\0\0>
9:
/ initialization program
47.
100036
.byte 1,3
9f-.-2
8:
sys break; 0
sys open; 6f-8b+core; 0
mov r0,r1
sys seek; 65.; 0
1:
mov r1,r0
sys read; 9f-8b+core; 512.
mov 9f,r5 / size
beq 1f
sys creat; 9f-8b+core+4; 0
mov r0,r2
movb 9f+2,0f
sys chmod; 9f-8b+core+4; 0:..
movb 9f+3,0f
sys chown; 9f-8b+core+4; 0:..
2:
tst r5
beq 2f
mov r1,r0
sys read; 9f-8b+core; 512.
mov $512.,0f
cmp r5,$512.
bhi 3f
mov r5,0f
3:
mov r2,r0
sys write; 9f-8b+core; 0:..
sub r0,r5
br 2b
2:
mov r2,r0
sys close
br 1b
1:
mov r1,r0
sys close
sys exec; 5f-8b+core; 4f-8b+core
sys exit
4:
5f-8b+core; 0
5:
</etc/init\0>
6:
</dev/tap0\0>
.even
9:
/ end of initialization data
0
.endif