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  
32  struct 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  
main(int argc,char * argv[])41  int 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