firmware/target/arm/pnx0101/kernel-pnx0101.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2007 by Tomasz Malesinski
  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 #include "config.h"
  22 #include "system.h"
  23 #include "kernel.h"
  24
  25 void timer_handler(void)
  26 {
  27     /* Run through the list of tick tasks */
  28     call_tick_tasks();
  29
  30     TIMER0.clr = 0;
  31 }
  32
  33 void tick_start(unsigned int interval_in_ms)
  34 {
  35     TIMER0.ctrl &= ~0x80; /* Disable the counter */
  36     TIMER0.ctrl |= 0x40;  /* Reload after counting down to zero */
  37     TIMER0.load = 3000000 * interval_in_ms / 1000;
  38     TIMER0.ctrl &= ~0xc;  /* No prescaler */
  39     TIMER0.clr = 1;       /* Clear the interrupt request */
  40
  41     irq_set_int_handler(IRQ_TIMER0, timer_handler);
  42     irq_enable_int(IRQ_TIMER0);
  43
  44     TIMER0.ctrl |= 0x80;  /* Enable the counter */
  45 }