LXR uboot/examples/standalone/interrupt.c

   1/*
   2 * (C) Copyright 2006
   3 * Detlev Zundel, DENX Software Engineering, dzu@denx.de.
   4 *
   5 * SPDX-License-Identifier:     GPL-2.0+
   6 *
   7 * This is a very simple standalone application demonstrating
   8 * catching IRQs on the MPC52xx architecture.
   9 *
  10 * The interrupt to be intercepted can be specified as an argument
  11 * to the application.  Specifying nothing will intercept IRQ1 on the
  12 * MPC5200 platform.  On the CR825 carrier board from MicroSys this
  13 * maps to the ABORT switch :)
  14 *
  15 * Note that the specified vector is only a logical number specified
  16 * by the respective header file.
  17 */
  18
  19#include <common.h>
  20#include <exports.h>
  21#include <config.h>
  22
  23#if defined(CONFIG_MPC5xxx)
  24#define DFL_IRQ MPC5XXX_IRQ1
  25#else
  26#define DFL_IRQ 0
  27#endif
  28
  29static void irq_handler (void *arg);
  30
  31int interrupt (int argc, char * const argv[])
  32{
  33        int c, irq = -1;
  34
  35        app_startup (argv);
  36
  37        if (argc > 1)
  38                irq = simple_strtoul (argv[1], NULL, 0);
  39        if ((irq < 0) || (irq > NR_IRQS))
  40                irq = DFL_IRQ;
  41
  42        printf ("Installing handler for irq vector %d and doing busy wait\n",
  43                irq);
  44        printf ("Press 'q' to quit\n");
  45
  46        /* Install interrupt handler */
  47        install_hdlr (irq, irq_handler, NULL);
  48        while ((c = getc ()) != 'q') {
  49                printf ("Ok, ok, I am still alive!\n");
  50        }
  51
  52        free_hdlr (irq);
  53        printf ("\nInterrupt handler has been uninstalled\n");
  54
  55        return (0);
  56}
  57
  58/*
  59 * Handler for interrupt
  60 */
  61static void irq_handler (void *arg)
  62{
  63        /* just for demonstration */
  64        printf ("+");
  65}
  66