rom/timer/timervblank.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: VBlank server for the timer.device/timer.hidd
   6     Lang: english
   7 */
   8 #include <exec/types.h>
   9 #include <exec/execbase.h>
  10 #include <proto/exec.h>
  11 #include <proto/timer.h>
  12 #include <aros/debug.h>
  13
  14 #include "timer_intern.h"
  15 #undef SysBase
  16
  17 /*
  18     This is a slightly faster version of AddTime() that we use here. It
  19     also saves the function call overhead...
  20 */
  21 #define FastAddTime(d, s)\
  22     (d)->tv_micro += (s)->tv_micro;\
  23     (d)->tv_secs += (s)->tv_secs;\
  24     if((d)->tv_micro > 999999) {\
  25         (d)->tv_secs++;\
  26         (d)->tv_micro -= 1000000;\
  27     }
  28
  29 AROS_UFH4(ULONG, VBlankInt,
  30     AROS_UFHA(ULONG, dummy, A0),
  31     AROS_UFHA(struct TimerBase *, TimerBase, A1),
  32     AROS_UFHA(ULONG, dummy2, A5),
  33     AROS_UFHA(struct ExecBase *, SysBase, A6)
  34     )
  35 {
  36     AROS_USERFUNC_INIT
  37
  38     struct timerequest *tr, *next;
  39
  40     /*
  41         Firstly increment the current time. No need to Disable() here as
  42         there are no other interrupts that are allowed to interrupt us
  43         that can do anything with this.
  44     */
  45     FastAddTime(&TimerBase->tb_CurrentTime, &TimerBase->tb_VBlankTime);
  46     FastAddTime(&TimerBase->tb_Elapsed, &TimerBase->tb_VBlankTime);
  47
  48     TimerBase->tb_ticks_total++;
  49
  50     /*
  51         Go through the "wait for x seconds" list and return requests
  52         that have completed. A completed request is one whose time
  53         is less than that of the elapsed time.
  54     */
  55     tr = (struct timerequest *)TimerBase->tb_Lists[TL_VBLANK].mlh_Head;
  56
  57     while(tr && ((struct Node *)tr)->ln_Succ != NULL)
  58     {
  59         if(     (tr->tr_time.tv_secs < TimerBase->tb_Elapsed.tv_secs)
  60             ||  (    (tr->tr_time.tv_secs <= TimerBase->tb_Elapsed.tv_secs)
  61                  &&  (tr->tr_time.tv_micro < TimerBase->tb_Elapsed.tv_micro))
  62           )
  63         {
  64             /* This request has finished */
  65             next = (struct timerequest *)tr->tr_node.io_Message.mn_Node.ln_Succ;
  66             Remove((struct Node *)tr);
  67             tr->tr_time.tv_secs = tr->tr_time.tv_micro = 0;
  68             tr->tr_node.io_Error = 0;
  69             ReplyMsg((struct Message *)tr);
  70
  71             tr = next;
  72         }
  73         else
  74         {
  75             /*
  76                 The first request hasn't finished, as all requests are in
  77                 order, we don't bother searching through the remaining
  78             */
  79             tr = NULL;
  80         }
  81     }
  82
  83     /*
  84         The other this is the "wait until a specified time". Here a request
  85         is complete if the time we are waiting for is before the current time.
  86     */
  87     tr = (struct timerequest *)TimerBase->tb_Lists[TL_WAITVBL].mlh_Head;
  88
  89     while(tr && ((struct Node *)tr)->ln_Succ != NULL)
  90     {
  91         if(     (tr->tr_time.tv_secs <= TimerBase->tb_CurrentTime.tv_secs)
  92             &&  (tr->tr_time.tv_micro < TimerBase->tb_CurrentTime.tv_micro)
  93           )
  94         {
  95             /* This request has finished */
  96             next = (struct timerequest *)tr->tr_node.io_Message.mn_Node.ln_Succ;
  97             Remove((struct Node *)tr);
  98             tr->tr_time.tv_secs = tr->tr_time.tv_micro = 0;
  99             tr->tr_node.io_Error = 0;
 100             ReplyMsg((struct Message *)tr);
 101
 102             tr = next;
 103         }
 104         else
 105         {
 106             /*
 107                 The first request hasn't finished, as all requests are in
 108                 order, we don't bother searching through the remaining
 109             */
 110             tr = NULL;
 111         }
 112     }
 113
 114     return 0;
 115     AROS_USERFUNC_EXIT
 116 }
 117