LXR uboot/examples/interrupt.c

   1/*
   2 * (C) Copyright 2006
   3 * Detlev Zundel, DENX Software Engineering, dzu@denx.de.
   4 *
   5 * See file CREDITS for list of people who contributed to this
   6 * project.
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License as
  10 * published by the Free Software Foundation; either version 2 of
  11 * the License, or (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program; if not, write to the Free Software
  20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21 * MA 02111-1307 USA
  22 *
  23 * This is a very simple standalone application demonstrating
  24 * catching IRQs on the MPC52xx architecture.
  25 *
  26 * The interrupt to be intercepted can be specified as an argument
  27 * to the application.  Specifying nothing will intercept IRQ1 on the
  28 * MPC5200 platform.  On the CR825 carrier board from MicroSys this
  29 * maps to the ABORT switch :)
  30 *
  31 * Note that the specified vector is only a logical number specified
  32 * by the respective header file.
  33 */
  34
  35#include <common.h>
  36#include <exports.h>
  37#include <config.h>
  38
  39#if defined(CONFIG_MPC5xxx)
  40#define DFL_IRQ MPC5XXX_IRQ1
  41#else
  42#define DFL_IRQ 0
  43#endif
  44
  45static void irq_handler (void *arg);
  46
  47int interrupt (int argc, char *argv[])
  48{
  49        int c, irq = -1;
  50
  51        app_startup (argv);
  52
  53        if (argc > 1)
  54                irq = simple_strtoul (argv[1], NULL, 0);
  55        if ((irq < 0) || (irq > NR_IRQS))
  56                irq = DFL_IRQ;
  57
  58        printf ("Installing handler for irq vector %d and doing busy wait\n",
  59                irq);
  60        printf ("Press 'q' to quit\n");
  61
  62        /* Install interrupt handler */
  63        install_hdlr (irq, irq_handler, NULL);
  64        while ((c = getc ()) != 'q') {
  65                printf ("Ok, ok, I am still alive!\n");
  66        }
  67
  68        free_hdlr (irq);
  69        printf ("\nInterrupt handler has been uninstalled\n");
  70
  71        return (0);
  72}
  73
  74/*
  75 * Handler for interrupt
  76 */
  77static void irq_handler (void *arg)
  78{
  79        /* just for demonstration */
  80        printf ("+");
  81}
  82