arch/ppc/syslib/gen550_kgdb.c

   1 /*
   2  * Generic 16550 kgdb support intended to be useful on a variety
   3  * of platforms.  To enable this support, it is necessary to set
   4  * the CONFIG_GEN550 option.  Any virtual mapping of the serial
   5  * port(s) to be used can be accomplished by setting
   6  * ppc_md.early_serial_map to a platform-specific mapping function.
   7  *
   8  * Adapted from ppc4xx_kgdb.c.
   9  *
  10  * Author: Matt Porter <mporter@kernel.crashing.org>
  11  *
  12  * 2002-2004 (c) MontaVista Software, Inc.  This file is licensed under
  13  * the terms of the GNU General Public License version 2.  This program
  14  * is licensed "as is" without any warranty of any kind, whether express
  15  * or implied.
  16  */
  17
  18 #include <linux/types.h>
  19 #include <linux/kernel.h>
  20
  21 #include <asm/machdep.h>
  22
  23 extern unsigned long serial_init(int, void *);
  24 extern unsigned long serial_getc(unsigned long);
  25 extern unsigned long serial_putc(unsigned long, unsigned char);
  26
  27 #if defined(CONFIG_KGDB_TTYS0)
  28 #define KGDB_PORT 0
  29 #elif defined(CONFIG_KGDB_TTYS1)
  30 #define KGDB_PORT 1
  31 #elif defined(CONFIG_KGDB_TTYS2)
  32 #define KGDB_PORT 2
  33 #elif defined(CONFIG_KGDB_TTYS3)
  34 #define KGDB_PORT 3
  35 #else
  36 #error "invalid kgdb_tty port"
  37 #endif
  38
  39 static volatile unsigned int kgdb_debugport;
  40
  41 void putDebugChar(unsigned char c)
  42 {
  43         if (kgdb_debugport == 0)
  44                 kgdb_debugport = serial_init(KGDB_PORT, NULL);
  45
  46         serial_putc(kgdb_debugport, c);
  47 }
  48
  49 int getDebugChar(void)
  50 {
  51         if (kgdb_debugport == 0)
  52                 kgdb_debugport = serial_init(KGDB_PORT, NULL);
  53
  54         return(serial_getc(kgdb_debugport));
  55 }
  56
  57 void kgdb_interruptible(int enable)
  58 {
  59         return;
  60 }
  61
  62 void putDebugString(char* str)
  63 {
  64         while (*str != '\0') {
  65                 putDebugChar(*str);
  66                 str++;
  67         }
  68         putDebugChar('\r');
  69         return;
  70 }
  71
  72 /*
  73  * Note: gen550_init() must be called already on the port we are going
  74  * to use.
  75  */
  76 void
  77 gen550_kgdb_map_scc(void)
  78 {
  79         printk(KERN_DEBUG "kgdb init\n");
  80         if (ppc_md.early_serial_map)
  81                 ppc_md.early_serial_map();
  82         kgdb_debugport = serial_init(KGDB_PORT, NULL);
  83 }