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         unsigned long post_word;
  79         char *s;
  80
  81         log_buf = (unsigned char *)(gd->bd->bi_memsize-LOGBUFF_LEN);
  82         ext_tag = (unsigned long *)(log_buf)-4;
  83         ext_log_start = (unsigned long *)(log_buf)-3;
  84         ext_log_size = (unsigned long *)(log_buf)-2;
  85         ext_logged_chars = (unsigned long *)(log_buf)-1;
  86         post_word = post_word_load();
  87 #ifdef CONFIG_POST
  88         /* The post routines have setup the word so we can simply test it */
  89         if (post_word_load () & POST_COLDBOOT) {
  90                 logged_chars = log_size = log_start = 0;
  91                 *ext_tag = LOGBUFF_MAGIC;
  92         }
  93 #else
  94         /* No post routines, so we do our own checking                    */
  95         if (post_word != LOGBUFF_MAGIC) {
  96                 logged_chars = log_size = log_start = 0;
  97                 post_word_store (LOGBUFF_MAGIC);
  98                 *ext_tag = LOGBUFF_MAGIC;
  99         }
 100 #endif
 101         /* Initialize default loglevel if present */
 102         if ((s = getenv ("loglevel")) != NULL)
 103                 console_loglevel = (int)simple_strtoul (s, NULL, 10);
 104
 105         gd->post_log_word |= LOGBUFF_INITIALIZED;
 106 }
 107
 108 int drv_logbuff_init (void)
 109 {
 110         device_t logdev;
 111         int rc;
 112
 113         /* Device initialization */
 114         memset (&logdev, 0, sizeof (logdev));
 115
 116         strcpy (logdev.name, "logbuff");
 117         logdev.ext   = 0;                       /* No extensions */
 118         logdev.flags = DEV_FLAGS_OUTPUT;        /* Output only */
 119         logdev.putc  = logbuff_putc;            /* 'putc' function */
 120         logdev.puts  = logbuff_puts;            /* 'puts' function */
 121
 122         rc = device_register (&logdev);
 123
 124         return (rc == 0) ? 1 : rc;
 125 }
 126
 127 static void logbuff_putc (const char c)
 128 {
 129         char buf[2];
 130         buf[0] = c;
 131         buf[1] = '\0';
 132         logbuff_printk (buf);
 133 }
 134
 135 static void logbuff_puts (const char *s)
 136 {
 137         logbuff_printk (s);
 138 }
 139
 140 void logbuff_log(char *msg)
 141 {
 142         DECLARE_GLOBAL_DATA_PTR;
 143
 144         if ((gd->post_log_word & LOGBUFF_INITIALIZED)) {
 145                 logbuff_printk (msg);
 146         } else {
 147                 /* Can happen only for pre-relocated errors as logging */
 148                 /* at that stage should be disabled                    */
 149                 puts (msg);
 150         }
 151 }
 152
 153 /*
 154  * Subroutine:  do_log
 155  *
 156  * Description: Handler for 'log' command..
 157  *
 158  * Inputs:      argv[1] contains the subcommand
 159  *
 160  * Return:      None
 161  *
 162  */
 163 int do_log (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 164 {
 165         char *s;
 166         unsigned long i;
 167
 168         if (strcmp(argv[1],"append") == 0) {
 169                 /* Log concatenation of all arguments separated by spaces */
 170                 for (i=2; i<argc; i++) {
 171                         logbuff_printk (argv[i]);
 172                         logbuff_putc ((i<argc-1) ? ' ' : '\n');
 173                 }
 174                 return 0;
 175         }
 176
 177         switch (argc) {
 178
 179         case 2:
 180                 if (strcmp(argv[1],"show") == 0) {
 181                         for (i=0; i < (log_size&LOGBUFF_MASK); i++) {
 182                                 s = (char *)log_buf+((log_start+i)&LOGBUFF_MASK);
 183                                 putc (*s);
 184                         }
 185                         return 0;
 186                 } else if (strcmp(argv[1],"reset") == 0) {
 187                         log_start    = 0;
 188                         log_size     = 0;
 189                         logged_chars = 0;
 190                         return 0;
 191                 } else if (strcmp(argv[1],"info") == 0) {
 192                         printf ("Logbuffer   at  %08lx\n", (unsigned long)log_buf);
 193                         printf ("log_start    =  %08lx\n", log_start);
 194                         printf ("log_size     =  %08lx\n", log_size);
 195                         printf ("logged_chars =  %08lx\n", logged_chars);
 196                         return 0;
 197                 }
 198                 printf ("Usage:\n%s\n", cmdtp->usage);
 199                 return 1;
 200
 201         default:
 202                 printf ("Usage:\n%s\n", cmdtp->usage);
 203                 return 1;
 204         }
 205 }
 206 #if defined(CONFIG_LOGBUFFER)
 207 U_BOOT_CMD(
 208         log,     255,   1,      do_log,
 209         "log     - manipulate logbuffer\n",
 210         "info   - show pointer details\n"
 211         "log reset  - clear contents\n"
 212         "log show   - show contents\n"
 213         "log append <msg> - append <msg> to the logbuffer\n"
 214 );
 215 #endif  /* CONFIG_LOGBUFFER */
 216 static int logbuff_printk(const char *line)
 217 {
 218         int i;
 219         char *msg, *p, *buf_end;
 220         int line_feed;
 221         static signed char msg_level = -1;
 222
 223         strcpy (buf + 3, line);
 224         i = strlen (line);
 225         buf_end = buf + 3 + i;
 226         for (p = buf + 3; p < buf_end; p++) {
 227                 msg = p;
 228                 if (msg_level < 0) {
 229                         if (
 230                                 p[0] != '<' ||
 231                                 p[1] < '0' ||
 232                                 p[1] > '7' ||
 233                                 p[2] != '>'
 234                         ) {
 235                                 p -= 3;
 236                                 p[0] = '<';
 237                                 p[1] = default_message_loglevel + '0';
 238                                 p[2] = '>';
 239                         } else
 240                                 msg += 3;
 241                         msg_level = p[1] - '0';
 242                 }
 243                 line_feed = 0;
 244                 for (; p < buf_end; p++) {
 245                         log_buf[(log_start+log_size) & LOGBUFF_MASK] = *p;
 246                         if (log_size < LOGBUFF_LEN)
 247                                 log_size++;
 248                         else
 249                                 log_start++;
 250
 251                         logged_chars++;
 252                         if (*p == '\n') {
 253                                 line_feed = 1;
 254                                 break;
 255                         }
 256                 }
 257                 if (msg_level < console_loglevel) {
 258                         printf("%s", msg);
 259                 }
 260                 if (line_feed)
 261                         msg_level = -1;
 262         }
 263         return i;
 264 }
 265
 266 #endif /* (CONFIG_LOGBUFFER) */