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 <linux/sched.h>
  17 #include <asm/ppcdebug.h>
  18 #include <asm/processor.h>
  19
  20 void (*udbg_putc)(unsigned char c);
  21 unsigned char (*udbg_getc)(void);
  22 int (*udbg_getc_poll)(void);
  23
  24 void udbg_puts(const char *s)
  25 {
  26         if (udbg_putc) {
  27                 char c;
  28
  29                 if (s && *s != '\0') {
  30                         while ((c = *s++) != '\0')
  31                                 udbg_putc(c);
  32                 }
  33         }
  34 #if 0
  35         else {
  36                 printk("%s", s);
  37         }
  38 #endif
  39 }
  40
  41 int udbg_write(const char *s, int n)
  42 {
  43         int remain = n;
  44         char c;
  45
  46         if (!udbg_putc)
  47                 return 0;
  48
  49         if (s && *s != '\0') {
  50                 while (((c = *s++) != '\0') && (remain-- > 0)) {
  51                         udbg_putc(c);
  52                 }
  53         }
  54
  55         return n - remain;
  56 }
  57
  58 int udbg_read(char *buf, int buflen)
  59 {
  60         char c, *p = buf;
  61         int i;
  62
  63         if (!udbg_getc)
  64                 return 0;
  65
  66         for (i = 0; i < buflen; ++i) {
  67                 do {
  68                         c = udbg_getc();
  69                 } while (c == 0x11 || c == 0x13);
  70                 if (c == 0)
  71                         break;
  72                 *p++ = c;
  73         }
  74
  75         return i;
  76 }
  77
  78 void udbg_console_write(struct console *con, const char *s, unsigned int n)
  79 {
  80         udbg_write(s, n);
  81 }
  82
  83 #define UDBG_BUFSIZE 256
  84 void udbg_printf(const char *fmt, ...)
  85 {
  86         unsigned char buf[UDBG_BUFSIZE];
  87         va_list args;
  88
  89         va_start(args, fmt);
  90         vsnprintf(buf, UDBG_BUFSIZE, fmt, args);
  91         udbg_puts(buf);
  92         va_end(args);
  93 }
  94
  95 /* Special print used by PPCDBG() macro */
  96 void udbg_ppcdbg(unsigned long debug_flags, const char *fmt, ...)
  97 {
  98         unsigned long active_debugs = debug_flags & ppc64_debug_switch;
  99
 100         if (active_debugs) {
 101                 va_list ap;
 102                 unsigned char buf[UDBG_BUFSIZE];
 103                 unsigned long i, len = 0;
 104
 105                 for (i=0; i < PPCDBG_NUM_FLAGS; i++) {
 106                         if (((1U << i) & active_debugs) &&
 107                             trace_names[i]) {
 108                                 len += strlen(trace_names[i]);
 109                                 udbg_puts(trace_names[i]);
 110                                 break;
 111                         }
 112                 }
 113
 114                 snprintf(buf, UDBG_BUFSIZE, " [%s]: ", current->comm);
 115                 len += strlen(buf);
 116                 udbg_puts(buf);
 117
 118                 while (len < 18) {
 119                         udbg_puts(" ");
 120                         len++;
 121                 }
 122
 123                 va_start(ap, fmt);
 124                 vsnprintf(buf, UDBG_BUFSIZE, fmt, ap);
 125                 udbg_puts(buf);
 126                 va_end(ap);
 127         }
 128 }
 129
 130 unsigned long udbg_ifdebug(unsigned long flags)
 131 {
 132         return (flags & ppc64_debug_switch);
 133 }