firmware/target/arm/as3525/timer-as3525.c

   1 /***************************************************************************
   2 *             __________               __   ___.
   3 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7 *                     \/            \/     \/    \/            \/
   8 * $Id$
   9 *
  10 * Copyright (C) 2008 Rafaël Carré
  11 *
  12 * This program is free software; you can redistribute it and/or
  13 * modify it under the terms of the GNU General Public License
  14 * as published by the Free Software Foundation; either version 2
  15 * of the License, or (at your option) any later version.
  16 *
  17 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18 * KIND, either express or implied.
  19 *
  20 ****************************************************************************/
  21
  22 #include "as3525.h"
  23 #include "timer.h"
  24 #include "stdlib.h"
  25
  26 void INT_TIMER1(void)
  27 {
  28     if (pfn_timer != NULL)
  29         pfn_timer();
  30
  31     TIMER1_INTCLR = 0; /* clear interrupt */
  32 }
  33
  34 bool timer_set(long cycles, bool start)
  35 {
  36     if (start)
  37     {
  38         if (pfn_unregister != NULL)
  39         {
  40             pfn_unregister();
  41             pfn_unregister = NULL;
  42         }
  43     }
  44
  45     TIMER1_LOAD = TIMER1_BGLOAD = cycles;
  46     /* /!\ bit 4 (reserved) must not be modified
  47      * periodic mode, interrupt enabled, no prescale, 32 bits counter */
  48     TIMER1_CONTROL = (TIMER1_CONTROL & (1<<4)) |
  49                      TIMER_ENABLE |
  50                      TIMER_PERIODIC |
  51                      TIMER_INT_ENABLE |
  52                      TIMER_32_BIT;
  53     return true;
  54 }
  55
  56 bool timer_start(void)
  57 {
  58     CGU_PERI |= CGU_TIMER1_CLOCK_ENABLE;    /* enable peripheral */
  59     VIC_INT_ENABLE = INTERRUPT_TIMER1;
  60     return true;
  61 }
  62
  63 void timer_stop(void)
  64 {
  65     TIMER1_CONTROL &= 0x10; /* disable timer 1 (don't modify bit 4) */
  66     VIC_INT_EN_CLEAR = INTERRUPT_TIMER1;  /* disable interrupt */
  67     CGU_PERI &= ~CGU_TIMER1_CLOCK_ENABLE;   /* disable peripheral */
  68 }