arch/ppc64/kernel/udbg.c

   1 /*
   2  * polling mode stateless debugging stuff, originally for NS16550 Serial Ports
   3  *
   4  * c 2001 PPC 64 Team, IBM Corp
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <stdarg.h>
  13 #define WANT_PPCDBG_TAB /* Only defined here */
  14 #include <linux/config.h>
  15 #include <linux/types.h>
  16 #include <asm/ppcdebug.h>
  17 #include <asm/processor.h>
  18 #include <asm/uaccess.h>
  19 #include <asm/machdep.h>
  20 #include <asm/io.h>
  21 #include <asm/prom.h>
  22
  23 void (*udbg_putc)(unsigned char c);
  24 unsigned char (*udbg_getc)(void);
  25 int (*udbg_getc_poll)(void);
  26
  27 void udbg_puts(const char *s)
  28 {
  29         if (udbg_putc) {
  30                 char c;
  31
  32                 if (s && *s != '\0') {
  33                         while ((c = *s++) != '\0')
  34                                 udbg_putc(c);
  35                 }
  36         }
  37 #if 0
  38         else {
  39                 printk("%s", s);
  40         }
  41 #endif
  42 }
  43
  44 int udbg_write(const char *s, int n)
  45 {
  46         int remain = n;
  47         char c;
  48
  49         if (!udbg_putc)
  50                 return 0;
  51
  52         if (s && *s != '\0') {
  53                 while (((c = *s++) != '\0') && (remain-- > 0)) {
  54                         udbg_putc(c);
  55                 }
  56         }
  57
  58         return n - remain;
  59 }
  60
  61 int udbg_read(char *buf, int buflen)
  62 {
  63         char c, *p = buf;
  64         int i;
  65
  66         if (!udbg_getc)
  67                 return 0;
  68
  69         for (i = 0; i < buflen; ++i) {
  70                 do {
  71                         c = udbg_getc();
  72                 } while (c == 0x11 || c == 0x13);
  73                 if (c == 0)
  74                         break;
  75                 *p++ = c;
  76         }
  77
  78         return i;
  79 }
  80
  81 void udbg_console_write(struct console *con, const char *s, unsigned int n)
  82 {
  83         udbg_write(s, n);
  84 }
  85
  86 #define UDBG_BUFSIZE 256
  87 void udbg_printf(const char *fmt, ...)
  88 {
  89         unsigned char buf[UDBG_BUFSIZE];
  90         va_list args;
  91
  92         va_start(args, fmt);
  93         vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
  94         udbg_puts(buf);
  95         va_end(args);
  96 }
  97
  98 /* Special print used by PPCDBG() macro */
  99 void udbg_ppcdbg(unsigned long debug_flags, const char *fmt, ...)
 100 {
 101         unsigned long active_debugs = debug_flags & ppc64_debug_switch;
 102
 103         if (active_debugs) {
 104                 va_list ap;
 105                 unsigned char buf[UDBG_BUFSIZE];
 106                 unsigned long i, len = 0;
 107
 108                 for (i=0; i < PPCDBG_NUM_FLAGS; i++) {
 109                         if (((1U << i) & active_debugs) &&
 110                             trace_names[i]) {
 111                                 len += strlen(trace_names[i]);
 112                                 udbg_puts(trace_names[i]);
 113                                 break;
 114                         }
 115                 }
 116
 117                 snprintf(buf, UDBG_BUFSIZE, " [%s]: ", current->comm);
 118                 len += strlen(buf);
 119                 udbg_puts(buf);
 120
 121                 while (len < 18) {
 122                         udbg_puts(" ");
 123                         len++;
 124                 }
 125
 126                 va_start(ap, fmt);
 127                 vsnprintf(buf, UDBG_BUFSIZE, fmt, ap);
 128                 udbg_puts(buf);
 129                 va_end(ap);
 130         }
 131 }
 132
 133 unsigned long udbg_ifdebug(unsigned long flags)
 134 {
 135         return (flags & ppc64_debug_switch);
 136 }