arch/ppc/syslib/gen550_kgdb.c

   1 /*
   2  * arch/ppc/syslib/gen550_kgdb.c
   3  *
   4  * Generic 16550 kgdb support intended to be useful on a variety
   5  * of platforms.  To enable this support, it is necessary to set
   6  * the CONFIG_GEN550 option.  Any virtual mapping of the serial
   7  * port(s) to be used can be accomplished by setting
   8  * ppc_md.early_serial_map to a platform-specific mapping function.
   9  *
  10  * Adapted from ppc4xx_kgdb.c.
  11  *
  12  * Author: Matt Porter <mporter@kernel.crashing.org>
  13  *
  14  * 2002-2004 (c) MontaVista Software, Inc.  This file is licensed under
  15  * the terms of the GNU General Public License version 2.  This program
  16  * is licensed "as is" without any warranty of any kind, whether express
  17  * or implied.
  18  */
  19
  20 #include <linux/config.h>
  21 #include <linux/types.h>
  22 #include <linux/kernel.h>
  23
  24 #include <asm/machdep.h>
  25
  26 extern unsigned long serial_init(int, void *);
  27 extern unsigned long serial_getc(unsigned long);
  28 extern unsigned long serial_putc(unsigned long, unsigned char);
  29
  30 #if defined(CONFIG_KGDB_TTYS0)
  31 #define KGDB_PORT 0
  32 #elif defined(CONFIG_KGDB_TTYS1)
  33 #define KGDB_PORT 1
  34 #elif defined(CONFIG_KGDB_TTYS2)
  35 #define KGDB_PORT 2
  36 #elif defined(CONFIG_KGDB_TTYS3)
  37 #define KGDB_PORT 3
  38 #else
  39 #error "invalid kgdb_tty port"
  40 #endif
  41
  42 static volatile unsigned int kgdb_debugport;
  43
  44 void putDebugChar(unsigned char c)
  45 {
  46         if (kgdb_debugport == 0)
  47                 kgdb_debugport = serial_init(KGDB_PORT, NULL);
  48
  49         serial_putc(kgdb_debugport, c);
  50 }
  51
  52 int getDebugChar(void)
  53 {
  54         if (kgdb_debugport == 0)
  55                 kgdb_debugport = serial_init(KGDB_PORT, NULL);
  56
  57         return(serial_getc(kgdb_debugport));
  58 }
  59
  60 void kgdb_interruptible(int enable)
  61 {
  62         return;
  63 }
  64
  65 void putDebugString(char* str)
  66 {
  67         while (*str != '\0') {
  68                 putDebugChar(*str);
  69                 str++;
  70         }
  71         putDebugChar('\r');
  72         return;
  73 }
  74
  75 /*
  76  * Note: gen550_init() must be called already on the port we are going
  77  * to use.
  78  */
  79 void
  80 gen550_kgdb_map_scc(void)
  81 {
  82         printk(KERN_DEBUG "kgdb init\n");
  83         if (ppc_md.early_serial_map)
  84                 ppc_md.early_serial_map();
  85         kgdb_debugport = serial_init(KGDB_PORT, NULL);
  86 }