view level3/modules/nitro.asm @ 2630:e310e8613606

Fixed earlier change from yesterday due to misunderstanding of ordering of 6809 vectors on CoCo 1/2...
author Boisy Pitre <boisy.pitre@nuance.com>
date Sun, 26 Feb 2012 16:22:27 -0600
parents 87b07a1be8a0
children d0e8324af298
line wrap: on
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********************************************************************
* NitrOS9 - Sets up NitrOS-9 Level 3
*
* $Id$
*
* Edt/Rev  YYYY/MM/DD  Modified by
* Comment
* ------------------------------------------------------------------
*          ????/??/??  Alan DeKok
* Created.

         nam   NitrOS9
         ttl   Sets up NitrOS-9 Level 3

         ifp1
         use   defsfile
         endc

tylg     set   Systm+Obj6309
atrv     set   ReEnt+rev
rev      set   $04
         mod   eom,name,tylg,atrv,Start,size
u0000    rmb   0
size     equ   .
name     equ   *
         fcs   /NitrOS9/
         fcb   $01

Start    ldd   #$10ff     illegal instruction, /0 trap
         std   >0
         ldd   #$0008
         std   >2
         ldd   #$20FE
         std   >4

* allocate a block of RAM for SCF drivers
         ldu   #eom       get the size of this module
         leax  eom,pc     point to the next module
         ldy   #L3.SCF

all.ram  bsr   f.modul    move some modules over
         tstb             did we, in fact, move any?
         beq   all.done   if not, we're done
         stb   ,y+        save the starting RAM block number
         bra   all.ram    and go get another block of RAM

* Verify the rest of the boot: start of old OS9p1 code
all.done ldd   <D.BtSz    get the size of the boot
         subr  u,d        take out the size of the modules we're skipping
* F$VBlock has NO exit conditions, and doesn't change any registers
         OS9   F$VBlock   go verify the rest of the OS9Boot file
* do NOT use U after this!

* set the DAT image of the allocate blocks to be RAMInUse, rather than
* Module In block
         ldx   <D.SysDAT  point to the system DAT image
         ldb   $0D,x      grab the block# of the last allocated block
         incb             account for block 0: leave SCF & RBF as ModInBlk
         lda   #RAMInUse  set the RAM to be in use...
         ldx   <D.BlkMap  point to system block allocation map

set.lp   sta   ,x+        allocate the RAM
         decb             count down
         bne   set.lp     continue until done

         ldx   <D.BlkMap  grab the block map again
         sta   <$3F,x     mark the boot track block as used, too.

* mark block 1 ($2000-$3FFF) in the system memory map as allocated
         ldx   <D.SysMem  ptr to low system memory
         ldd   #$0100+L3.Size  RAMInUse, N times
         leax  $20,x      to the start of block 1 in the block map
blk.lp   sta   ,x+        set it to be in use
         decb
         bne   blk.lp

* U = total size of the crap we've removed
         ldd   <D.BtSz    size of the bootfile
         subr  u,d        take out size of code we've removed
         std   <D.BtSz
         ldd   <D.BtPtr
         addr  u,d        point to new start of the OS9Booto file
         pshs  d          and save for later
         tfr   u,d         size of code we've taken out
         subd  #$00FF     round _down_ a page

         ldx   <D.SysMem  pt to system memory map
         ldb   <D.BtPtr   point to start of OS9Boot in memory
         abx              go to it

* remove the memory from the system memory map
m.lp     clr   ,x+        set the RAM to be not in use
         deca             count down the number of pages we've moved
         bne   m.lp       continue
         bra   x.done

         leax  -1,x       point to last unused byte
         tfr   x,d        move into an address register
         lsra
         lsra
         lsra
         lsra
         lsra             now A=block number of highest block
         ldb   <D.BtPtr
         lsrb
         lsrb
         lsrb
         lsrb
         lsrb
         subr  b,a        same block? (now A=number of blocks to delete)
         beq   x.done     yes, don't do anything

         ldu   <D.BlkMap  point to system-wide block map
         ldx   <D.SysDAT  pointer to system DAT image
         lslb             convert to DAT image offset
         incb             point to block number, not flag
         abx              point to the offset

x.loop   ldb   ,x++       grab a block number
         clr   b,u        mark the block as unused
         deca
         bne   x.loop     continue until done

x.done   puls  d          restore ptr to new start of the OS9Boot file
         std   <D.BtPtr   and save it again
         clrb
         rts

*============================================================================
*
* Copy the modules into local memory.
* Copied from [X] to a module called _end
* Entry: X = ptr to start at
*        U = size of stuff deleted so far
* Exit : X = ptr to module after _end module
*        U = total size of stuff deleted

f.modul  pshs  b,x,y,u    save start of area to move, size moved before
* grab the name: is it _end?
is.end   ldd   ,x
         cmpd  #$87Cd     is it a module?
         bne   f.exit     no, exit
         ldd   M$Name,x   get the name pointer
         ldd   d,x        get 2 bytes of the name
         cmpd  #$5F65     '_e'?
         beq   fnd.end    yes, found it

* skip this module if not at the end yet
         ldd   M$Size,x   grab the module size
         leax  d,x        go to the next module
         leau  d,u        add in the size of it
         bra   is.end     and continue looking for end

f.exit   clrb             we're done everything
         puls  a,x,y,u,pc

* copy modules over, and verify
fnd.end  ldy   1,s        restore ptr to start of area to move
         tfr   u,w        new size
         subw  5,s        take out old size: W = total size
         cmpw  #L3.Size*$FF   greater than the room available?
         bhs   f.exit     yes, exit without allocating RAM

* skip _end module
         ldd   M$Size,x   get size of the _end module
         leax  d,x        skip it
         leau  d,u
         stx   1,s        save new start ptr
         stu   5,s        and new size

* we've found blocks to move, so let's allocate some RAM
         ldb   #L3.Blks   1 block to allocate
         OS9   F$AllRAM   allocate some RAM

         std   >$0642     map it into system DAT image
         stb   >$FFA1     map into physical RAM
         stb   ,s         save starting block number

         ifeq  L3.Blks-2  more than 1 block?
         incb             yes, go up by a block
         std   >$0644     map it into the system DAT image
         stb   >$FFA2     and into the hardware
         endc

* move the modules to local RAM
         pshsw            save size of the block to move
         ldx   #L3.Start+L3.Size where to move the stuff to
         tfm   y+,x+      move it from the OS9Boot file to IOMan local memory

* verify the modules
         puls  d          grab the size of the block
         ldx   #L3.Start+L3.Size start ptr again
         OS9   F$VBlock   verify the block

* get A = total size (in pages) of stuff moved over
         addd  #L3.Size+$FF round up to the nearest block, adding in $20

* start with all local RAM deallocated
         ldx   #L3.Start  to the start of the block
         ldb   #L3.Size-1 number of pages to mark as free
clr.lp   clr   b,x        set them to be all clear.
         decb
         bpl   clr.lp     count down until B=-1

* allocate local RAM to the size of the modules we've moved over
         ldb   #RAMInUse  RAM in use
all.lp   stb   ,x+        make the page allocated
         deca             count down a page
         bne   all.lp     and continue

         lda   #'-        a hyphen
         jsr   <D.BtBug   print it out

* restore start, size pointers and exit
         puls  b,x,y,u,pc

         emod
eom      equ   *
         end