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 "config.h"
  23 #include "system.h"
  24 #include "timer.h"
  25 #include "stdlib.h"
  26
  27 void INT_TIMER1(void)
  28 {
  29     if (pfn_timer != NULL)
  30         pfn_timer();
  31
  32     TIMER1_INTCLR = 0; /* clear interrupt */
  33 }
  34
  35 bool timer_set(long cycles, bool start)
  36 {
  37     int oldstatus = disable_irq_save();
  38
  39     if (start)
  40     {
  41         if (pfn_unregister != NULL)
  42         {
  43             pfn_unregister();
  44             pfn_unregister = NULL;
  45         }
  46     }
  47
  48     TIMER1_LOAD = TIMER1_BGLOAD = cycles;
  49     /* /!\ bit 4 (reserved) must not be modified
  50      * periodic mode, interrupt enabled, no prescale, 32 bits counter */
  51     TIMER1_CONTROL = (TIMER1_CONTROL & (1<<4)) |
  52                      TIMER_ENABLE |
  53                      TIMER_PERIODIC |
  54                      TIMER_INT_ENABLE |
  55                      TIMER_32_BIT;
  56
  57     restore_irq(oldstatus);
  58
  59     return true;
  60 }
  61
  62 bool timer_start(void)
  63 {
  64     int oldstatus = disable_irq_save();
  65     CGU_PERI |= CGU_TIMER1_CLOCK_ENABLE;   /* enable peripheral */
  66     VIC_INT_ENABLE = INTERRUPT_TIMER1;
  67     restore_irq(oldstatus);
  68     return true;
  69 }
  70
  71 void timer_stop(void)
  72 {
  73     int oldstatus = disable_irq_save();
  74     TIMER1_CONTROL &= 0x10; /* disable timer 1 (don't modify bit 4) */
  75     VIC_INT_EN_CLEAR = INTERRUPT_TIMER1;  /* disable interrupt */
  76     CGU_PERI &= ~CGU_TIMER1_CLOCK_ENABLE;   /* disable peripheral */
  77     restore_irq(oldstatus);
  78 }