arch/.unmaintained/ppc-native/exec/permit.s

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 /*****************************************************************************
   7
   8     NAME
   9
  10         AROS_LH0(void, Permit,
  11
  12     LOCATION
  13         struct ExecBase *, SysBase, 23, Exec)
  14
  15     FUNCTION
  16         This function activates the dispatcher again after a call to Permit().
  17
  18     INPUTS
  19
  20     RESULT
  21
  22     NOTES
  23         This function preserves all registers.
  24
  25     EXAMPLE
  26
  27     BUGS
  28
  29     SEE ALSO
  30         Forbid(), Disable(), Enable()
  31
  32     INTERNALS
  33
  34     HISTORY
  35
  36 ******************************************************************************/
  37
  38         #include "machine.i"
  39
  40         .text
  41         .balign 4
  42         .globl  AROS_SLIB_ENTRY(Permit,Exec)
  43         .type   AROS_SLIB_ENTRY(Permit,Exec),@function
  44 AROS_SLIB_ENTRY(Permit,Exec):
  45         subr
  46         push    scr
  47
  48         /* decrement nesting count and return if there are Forbid()s left */
  49         lbz     scr,TDNestCnt(base)
  50         subic.  scr,scr,1
  51         stw     scr,TDNestCnt(base)
  52         bge     end
  53
  54         /* return if there are no delayed switches pending. */
  55         lwz     scr,AttnResched+1(base)
  56         cmpdi   scr,0
  57         beq     end
  58
  59         /* if IDNestCnt is not -1 taskswitches are still forbidden */
  60         lwz     scr,IDNestCnt(base)
  61         cmpdi   scr,0
  62         beq     end
  63
  64         /* Unset delayed switch bit and do the delayed switch */
  65         lwz     scr,0x12b(base)
  66         andi.   scr,scr,0x7f
  67         sth     scr,0x12b(base)
  68         jsrlvo  Switch,base
  69
  70         /* all done. */
  71
  72 end:    pop     scr
  73         rts
  74