sys/src/boot/pc/apm.s

   1 #include "x16.h"
   2 #include "mem.h"
   3
   4 TEXT apm(SB), $0
   5         MOVL id+4(SP), BX
   6         CALL rmode16(SB)
   7
   8         PUSHR(rBX)
   9         LWI(0x5300, rAX)
  10         BIOSCALL(0x15)
  11         POPR(rBX)
  12         JC noapm
  13
  14         PUSHR(rBX)
  15         LWI(0x5304, rAX)
  16         BIOSCALL(0x15)
  17         POPR(rBX)
  18         CLC
  19
  20         /* connect */
  21         LWI(0x5303, rAX)
  22         BIOSCALL(0x15)
  23         JC noapm
  24
  25         OPSIZE; PUSHR(rSI)
  26         OPSIZE; PUSHR(rBX)
  27         PUSHR(rDI)
  28         PUSHR(rDX)
  29         PUSHR(rCX)
  30         PUSHR(rAX)
  31
  32         LWI(CONFADDR, rDI)
  33
  34         /*
  35          * write APM data.  first four bytes are APM\0.
  36          */
  37         LWI(0x5041, rAX)
  38         STOSW
  39
  40         LWI(0x004d, rAX)
  41         STOSW
  42
  43         LWI(8, rCX)
  44 apmmove:
  45         POPR(rAX)
  46         STOSW
  47         LOOP apmmove
  48
  49 noapm:
  50         CALL16(pmode32(SB))
  51         RET