firmware/debug.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 by Linus Nielsen Feltzing
  11  *
  12  * All files in this archive are subject to the GNU General Public License.
  13  * See the file COPYING in the source tree root for full license agreement.
  14  *
  15  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  16  * KIND, either express or implied.
  17  *
  18  ****************************************************************************/
  19
  20 #include <string.h>
  21 #include <stdio.h>
  22 #include <stdarg.h>
  23 #include "config.h"
  24 #include "cpu.h"
  25 #ifdef HAVE_GDB_API
  26 #include "gdb_api.h"
  27 #endif
  28
  29 #ifdef DEBUG
  30 static char debugmembuf[200];
  31 #if CONFIG_CPU == SH7034
  32 static char debugbuf[400];
  33 #endif
  34 #endif
  35
  36 #ifndef SIMULATOR /* allow non archos platforms to display output */
  37 #include "kernel.h"
  38 #include "system.h"
  39
  40 #ifdef DEBUG
  41 #if CONFIG_CPU == SH7034 /* these are still very SH-oriented */
  42 void debug_init(void)
  43 {
  44     /* Clear it all! */
  45     SSR1 &= ~(SCI_RDRF | SCI_ORER | SCI_PER | SCI_FER);
  46
  47     /* This enables the serial Rx interrupt, to be able to exit into the
  48        debugger when you hit CTRL-C */
  49     SCR1 |= 0x40;
  50     SCR1 &= ~0x80;
  51     IPRE |= 0xf000; /* Set to highest priority */
  52 }
  53
  54 static int debug_tx_ready(void)
  55 {
  56     return (SSR1 & SCI_TDRE);
  57 }
  58
  59 static void debug_tx_char(char ch)
  60 {
  61     while (!debug_tx_ready())
  62     {
  63         ;
  64     }
  65
  66     /*
  67      * Write data into TDR and clear TDRE
  68      */
  69     TDR1 = ch;
  70     SSR1 &= ~SCI_TDRE;
  71 }
  72
  73 static void debug_handle_error(char ssr)
  74 {
  75     (void)ssr;
  76     SSR1 &= ~(SCI_ORER | SCI_PER | SCI_FER);
  77 }
  78
  79 static int debug_rx_ready(void)
  80 {
  81    char ssr;
  82
  83    ssr = SSR1 & ( SCI_PER | SCI_FER | SCI_ORER );
  84    if ( ssr )
  85       debug_handle_error ( ssr );
  86    return SSR1 & SCI_RDRF;
  87 }
  88
  89 static char debug_rx_char(void)
  90 {
  91    char ch;
  92    char ssr;
  93
  94    while (!debug_rx_ready())
  95    {
  96       ;
  97    }
  98
  99    ch = RDR1;
 100    SSR1 &= ~SCI_RDRF;
 101
 102    ssr = SSR1 & (SCI_PER | SCI_FER | SCI_ORER);
 103
 104    if (ssr)
 105       debug_handle_error (ssr);
 106
 107    return ch;
 108 }
 109
 110 static const char hexchars[] = "0123456789abcdef";
 111
 112 static char highhex(int  x)
 113 {
 114    return hexchars[(x >> 4) & 0xf];
 115 }
 116
 117 static char lowhex(int  x)
 118 {
 119    return hexchars[x & 0xf];
 120 }
 121
 122 static void putpacket (const char *buffer)
 123 {
 124     register  int checksum;
 125
 126     const char *src = buffer;
 127
 128    /* Special debug hack. Shut off the Rx IRQ during I/O to prevent the debug
 129       stub from interrupting the message */
 130     SCR1 &= ~0x40;
 131
 132     debug_tx_char ('$');
 133     checksum = 0;
 134
 135     while (*src)
 136     {
 137         int runlen;
 138
 139         /* Do run length encoding */
 140         for (runlen = 0; runlen < 100; runlen ++)
 141         {
 142             if (src[0] != src[runlen] || runlen == 99)
 143             {
 144                 if (runlen > 3)
 145                 {
 146                     int encode;
 147                     /* Got a useful amount */
 148                     debug_tx_char (*src);
 149                     checksum += *src;
 150                     debug_tx_char ('*');
 151                     checksum += '*';
 152                     checksum += (encode = runlen + ' ' - 4);
 153                     debug_tx_char (encode);
 154                     src += runlen;
 155                 }
 156                 else
 157                 {
 158                     debug_tx_char (*src);
 159                     checksum += *src;
 160                     src++;
 161                 }
 162                 break;
 163             }
 164         }
 165     }
 166
 167
 168     debug_tx_char ('#');
 169     debug_tx_char (highhex(checksum));
 170     debug_tx_char (lowhex(checksum));
 171
 172     /* Wait for the '+' */
 173     debug_rx_char();
 174
 175     /* Special debug hack. Enable the IRQ again */
 176     SCR1 |= 0x40;
 177 }
 178
 179
 180 /* convert the memory, pointed to by mem into hex, placing result in buf */
 181 /* return a pointer to the last char put in buf (null) */
 182 static char *mem2hex (const char *mem, char *buf, int count)
 183 {
 184     int i;
 185     int ch;
 186     for (i = 0; i < count; i++)
 187     {
 188         ch = *mem++;
 189         *buf++ = highhex (ch);
 190         *buf++ = lowhex (ch);
 191     }
 192     *buf = 0;
 193     return (buf);
 194 }
 195
 196 static void debug(const char *msg)
 197 {
 198     debugbuf[0] = 'O';
 199
 200     mem2hex(msg, &debugbuf[1], strlen(msg));
 201     putpacket(debugbuf);
 202 }
 203 #endif /* SH7034 */
 204
 205 #ifdef HAVE_GDB_API
 206 static void *get_api_function(int n)
 207 {
 208     struct gdb_api *api = (struct gdb_api *)GDB_API_ADDRESS;
 209     if (api->magic == GDB_API_MAGIC)
 210         return api->func[n];
 211     else
 212         return NULL;
 213 }
 214
 215 void breakpoint(void)
 216 {
 217     void (*f)(void) = get_api_function(0);
 218     if (f) (*f)();
 219 }
 220
 221 static void debug(char *msg)
 222 {
 223     void (*f)(char *) = get_api_function(1);
 224     if (f) (*f)(msg);
 225 }
 226
 227 void debug_init(void)
 228 {
 229 }
 230
 231 #endif /* HAVE_GDB_API */
 232 #endif /* end of DEBUG section */
 233
 234 #ifdef __GNUC__
 235 void debugf(const char *fmt, ...)
 236 #endif
 237 {
 238 #ifdef DEBUG
 239     va_list ap;
 240
 241     va_start(ap, fmt);
 242     vsnprintf(debugmembuf, sizeof(debugmembuf), fmt, ap);
 243     va_end(ap);
 244     debug(debugmembuf);
 245 #else
 246     (void)fmt;
 247 #endif
 248 }
 249
 250 #endif