common/cmd_log.c

   1 /*
   2  * (C) Copyright 2002
   3  * Detlev Zundel, DENX Software Engineering, dzu@denx.de.
   4  *
   5  * Code used from linux/kernel/printk.c
   6  * Copyright (C) 1991, 1992  Linus Torvalds
   7  *
   8  * See file CREDITS for list of people who contributed to this
   9  * project.
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License as
  13  * published by the Free Software Foundation; either version 2 of
  14  * the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  24  * MA 02111-1307 USA
  25  *
  26  * Comments:
  27  *
  28  * After relocating the code, the environment variable "loglevel" is
  29  * copied to console_loglevel.  The functionality is similar to the
  30  * handling in the Linux kernel, i.e. messages logged with a priority
  31  * less than console_loglevel are also output to stdout.
  32  *
  33  * If you want messages with the default level (e.g. POST messages) to
  34  * appear on stdout also, make sure the environment variable
  35  * "loglevel" is set at boot time to a number higher than
  36  * default_message_loglevel below.
  37  */
  38
  39 /*
  40  * Logbuffer handling routines
  41  */
  42
  43 #include <common.h>
  44 #include <command.h>
  45 #include <devices.h>
  46 #include <post.h>
  47 #include <logbuff.h>
  48
  49 #if defined(CONFIG_LOGBUFFER)
  50
  51 /* Local prototypes */
  52 static void logbuff_putc (const char c);
  53 static void logbuff_puts (const char *s);
  54 static int logbuff_printk(const char *line);
  55
  56 static char buf[1024];
  57
  58 /* This combination will not print messages with the default loglevel */
  59 static unsigned console_loglevel = 3;
  60 static unsigned default_message_loglevel = 4;
  61 static unsigned char *log_buf = NULL;
  62 static unsigned long *ext_log_size;
  63 static unsigned long *ext_log_start;
  64 static unsigned long *ext_logged_chars;
  65 #define log_size (*ext_log_size)
  66 #define log_start (*ext_log_start)
  67 #define logged_chars (*ext_logged_chars)
  68
  69 /* Forced by code, eh! */
  70 #define LOGBUFF_MAGIC 0xc0de4ced
  71
  72 /* The mapping used here has to be the same as in setup_ext_logbuff ()
  73    in linux/kernel/printk */
  74 void logbuff_init_ptrs (void)
  75 {
  76         DECLARE_GLOBAL_DATA_PTR;
  77         unsigned long *ext_tag;
  78         char *s;
  79
  80         log_buf = (unsigned char *)(gd->bd->bi_memsize-LOGBUFF_LEN);
  81         ext_tag = (unsigned long *)(log_buf)-4;
  82         ext_log_start = (unsigned long *)(log_buf)-3;
  83         ext_log_size = (unsigned long *)(log_buf)-2;
  84         ext_logged_chars = (unsigned long *)(log_buf)-1;
  85         if (*ext_tag!=LOGBUFF_MAGIC) {
  86                 logged_chars = log_size = log_start = 0;
  87                 *ext_tag = LOGBUFF_MAGIC;
  88         }
  89         /* Initialize default loglevel if present */
  90         if ((s = getenv ("loglevel")) != NULL)
  91                 console_loglevel = (int)simple_strtoul (s, NULL, 10);
  92
  93         gd->post_log_word |= LOGBUFF_INITIALIZED;
  94 }
  95
  96 int drv_logbuff_init (void)
  97 {
  98         device_t logdev;
  99         int rc;
 100
 101         /* Device initialization */
 102         memset (&logdev, 0, sizeof (logdev));
 103
 104         strcpy (logdev.name, "logbuff");
 105         logdev.ext   = 0;                       /* No extensions */
 106         logdev.flags = DEV_FLAGS_OUTPUT;        /* Output only */
 107         logdev.putc  = logbuff_putc;            /* 'putc' function */
 108         logdev.puts  = logbuff_puts;            /* 'puts' function */
 109
 110         rc = device_register (&logdev);
 111
 112         return (rc == 0) ? 1 : rc;
 113 }
 114
 115 static void logbuff_putc (const char c)
 116 {
 117         char buf[2];
 118         buf[0] = c;
 119         buf[1] = '\0';
 120         logbuff_printk (buf);
 121 }
 122
 123 static void logbuff_puts (const char *s)
 124 {
 125         logbuff_printk (s);
 126 }
 127
 128 void logbuff_log(char *msg)
 129 {
 130         DECLARE_GLOBAL_DATA_PTR;
 131
 132         if ((gd->post_log_word & LOGBUFF_INITIALIZED)) {
 133                 logbuff_printk (msg);
 134         } else {
 135                 /* Can happen only for pre-relocated errors as logging */
 136                 /* at that stage should be disabled                    */
 137                 puts (msg);
 138         }
 139 }
 140
 141 /*
 142  * Subroutine:  do_log
 143  *
 144  * Description: Handler for 'log' command..
 145  *
 146  * Inputs:      argv[1] contains the subcommand
 147  *
 148  * Return:      None
 149  *
 150  */
 151 int do_log (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 152 {
 153         char *s;
 154         unsigned long i;
 155
 156         if (strcmp(argv[1],"append") == 0) {
 157                 /* Log concatenation of all arguments separated by spaces */
 158                 for (i=2; i<argc; i++) {
 159                         if (i<argc-1) {
 160                                 logbuff_printk (argv[i]);
 161                                 logbuff_putc (' ');
 162                         } else {
 163                                 logbuff_puts (argv[i]);
 164                         }
 165                 }
 166                 return 0;
 167         }
 168
 169         switch (argc) {
 170
 171         case 2:
 172                 if (strcmp(argv[1],"show") == 0) {
 173                         for (i=0; i < (log_size&LOGBUFF_MASK); i++) {
 174                                 s = log_buf+((log_start+i)&LOGBUFF_MASK);
 175                                 putc (*s);
 176                         }
 177                         return 0;
 178                 } else if (strcmp(argv[1],"reset") == 0) {
 179                         log_start    = 0;
 180                         log_size     = 0;
 181                         logged_chars = 0;
 182                         return 0;
 183                 } else if (strcmp(argv[1],"info") == 0) {
 184                         printf ("Logbuffer   at  %08lx\n", (unsigned long)log_buf);
 185                         printf ("log_start    =  %08lx\n", log_start);
 186                         printf ("log_size     =  %08lx\n", log_size);
 187                         printf ("logged_chars =  %08lx\n", logged_chars);
 188                         return 0;
 189                 }
 190                 printf ("Usage:\n%s\n", cmdtp->usage);
 191                 return 1;
 192
 193         default:
 194                 printf ("Usage:\n%s\n", cmdtp->usage);
 195                 return 1;
 196         }
 197 }
 198
 199 static int logbuff_printk(const char *line)
 200 {
 201         int i;
 202         char *msg, *p, *buf_end;
 203         int line_feed;
 204         static signed char msg_level = -1;
 205
 206         strcpy (buf + 3, line);
 207         i = strlen (line);
 208         buf_end = buf + 3 + i;
 209         for (p = buf + 3; p < buf_end; p++) {
 210                 msg = p;
 211                 if (msg_level < 0) {
 212                         if (
 213                                 p[0] != '<' ||
 214                                 p[1] < '0' ||
 215                                 p[1] > '7' ||
 216                                 p[2] != '>'
 217                         ) {
 218                                 p -= 3;
 219                                 p[0] = '<';
 220                                 p[1] = default_message_loglevel + '0';
 221                                 p[2] = '>';
 222                         } else
 223                                 msg += 3;
 224                         msg_level = p[1] - '0';
 225                 }
 226                 line_feed = 0;
 227                 for (; p < buf_end; p++) {
 228                         log_buf[(log_start+log_size) & LOGBUFF_MASK] = *p;
 229                         if (log_size < LOGBUFF_LEN)
 230                                 log_size++;
 231                         else
 232                                 log_start++;
 233
 234                         logged_chars++;
 235                         if (*p == '\n') {
 236                                 line_feed = 1;
 237                                 break;
 238                         }
 239                 }
 240                 if (msg_level < console_loglevel) {
 241                         printf("%s", msg);
 242                 }
 243                 if (line_feed)
 244                         msg_level = -1;
 245         }
 246         return i;
 247 }
 248
 249 #endif /* (CONFIG_LOGBUFFER) */