LXR linux/arch/m68k/tools/amiga/dmesg.c

   1/*
   2 *  linux/arch/m68k/tools/amiga/dmesg.c -- Retrieve the kernel messages stored
   3 *                                         in Chip RAM with the kernel command
   4 *                                         line option `debug=mem'.
   5 *
   6 *  © Copyright 1996 by Geert Uytterhoeven <geert@linux-m68k.org>
   7 *
   8 *
   9 *  Usage:
  10 *
  11 *      dmesg
  12 *      dmesg <CHIPMEM_END>
  13 *
  14 *
  15 *  This file is subject to the terms and conditions of the GNU General Public
  16 *  License.  See the file COPYING in the main directory of the Linux
  17 *  distribution for more details.
  18 */
  19
  20
  21#include <stdio.h>
  22#include <stdlib.h>
  23#include <unistd.h>
  24
  25
  26#define CHIPMEM_START   0x00000000
  27#define CHIPMEM_END     0x00200000      /* overridden by argv[1] */
  28
  29#define SAVEKMSG_MAGIC1 0x53415645      /* 'SAVE' */
  30#define SAVEKMSG_MAGIC2 0x4B4D5347      /* 'KMSG' */
  31
  32struct savekmsg {
  33    u_long magic1;      /* SAVEKMSG_MAGIC1 */
  34    u_long magic2;      /* SAVEKMSG_MAGIC2 */
  35    u_long magicptr;    /* address of magic1 */
  36    u_long size;
  37    char data[];
  38};
  39
  40
  41int main(int argc, char *argv[])
  42{
  43    u_long start = CHIPMEM_START, end = CHIPMEM_END, p;
  44    int found = 0;
  45    struct savekmsg *m = NULL;
  46
  47    if (argc >= 2)
  48        end = strtoul(argv[1], NULL, 0);
  49    printf("Searching for SAVEKMSG magic...\n");
  50    for (p = start; p <= end-sizeof(struct savekmsg); p += 4) {
  51        m = (struct savekmsg *)p;
  52        if ((m->magic1 == SAVEKMSG_MAGIC1) && (m->magic2 == SAVEKMSG_MAGIC2) &&
  53            (m->magicptr == p)) {
  54            found = 1;
  55            break;
  56        }
  57    }
  58    if (!found)
  59        printf("Not found\n");
  60    else {
  61        printf("Found %ld bytes at 0x%08lx\n", m->size, (u_long)&m->data);
  62        puts(">>>>>>>>>>>>>>>>>>>>");
  63        fflush(stdout);
  64        write(1, &m->data, m->size);
  65        fflush(stdout);
  66        puts("<<<<<<<<<<<<<<<<<<<<");
  67    }
  68    return(0);
  69}
  70