gdb/ppc-bdm.c

   1 /* Remote target communications for the Macraigor Systems BDM Wiggler
   2    talking to a Motorola PPC 8xx ADS board
   3    Copyright 1996, 1997 Free Software Foundation, Inc.
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22 #include "gdbcore.h"
  23 #include "gdb_string.h"
  24 #include <fcntl.h>
  25 #include "frame.h"
  26 #include "inferior.h"
  27 #include "bfd.h"
  28 #include "symfile.h"
  29 #include "target.h"
  30 #include "wait.h"
  31 #include "gdbcmd.h"
  32 #include "objfiles.h"
  33 #include "gdb-stabs.h"
  34 #include <sys/types.h>
  35 #include <signal.h>
  36 #include "serial.h"
  37 #include "ocd.h"
  38
  39 static void bdm_ppc_open PARAMS ((char *name, int from_tty));
  40
  41 static int bdm_ppc_wait PARAMS ((int pid,
  42                                  struct target_waitstatus *target_status));
  43
  44 static void bdm_ppc_fetch_registers PARAMS ((int regno));
  45
  46 static void bdm_ppc_store_registers PARAMS ((int regno));
  47
  48 extern struct target_ops bdm_ppc_ops;   /* Forward decl */
  49 \f
  50 /*#define BDM_NUM_REGS 71*/
  51 #define BDM_NUM_REGS 24
  52
  53 #define BDM_REGMAP \
  54         2048, 2049, 2050, 2051, 2052, 2053, 2054, 2055, /* r0-r7 */ \
  55         2056, 2057, 2058, 2059, 2060, 2061, 2062, 2063, /* r8-r15 */ \
  56         2064, 2065, 2066, 2067, 2068, 2069, 2070, 2071, /* r16-r23 */ \
  57         2072, 2073, 2074, 2075, 2076, 2077, 2078, 2079, /* r24-r31 */ \
  58 \
  59         2080, 2082, 2084, 2086, 2088, 2090, 2092, 2094, /* fp0->fp8 */ \
  60         2096, 2098, 2100, 2102, 2104, 2106, 2108, 2110, /* fp0->fp8 */ \
  61         2112, 2114, 2116, 2118, 2120, 2122, 2124, 2126, /* fp0->fp8 */ \
  62         2128, 2130, 2132, 2134, 2136, 2138, 2140, 2142, /* fp0->fp8 */ \
  63 \
  64         26,        /* pc (SRR0 (SPR 26)) */ \
  65         2146,      /* ps (MSR) */ \
  66         2144,      /* cnd (CR) */ \
  67         8,         /* lr (SPR 8) */ \
  68         9,         /* cnt (CTR (SPR 9)) */ \
  69         1,         /* xer (SPR 1) */ \
  70         0,         /* mq (SPR 0) */
  71
  72 \f
  73 char nowatchdog[4] = {0xff,0xff,0xff,0x88};
  74
  75 /* Open a connection to a remote debugger.
  76    NAME is the filename used for communication.  */
  77
  78 static void
  79 bdm_ppc_open (name, from_tty)
  80      char *name;
  81      int from_tty;
  82 {
  83   CORE_ADDR watchdogaddr = 0xff000004;
  84
  85   ocd_open (name, from_tty, OCD_TARGET_MOTO_PPC, &bdm_ppc_ops);
  86
  87   /* We want interrupts to drop us into debugging mode. */
  88   /* Modify the DER register to accomplish this. */
  89   ocd_write_bdm_register (149, 0x20024000);
  90
  91   /* Disable watchdog timer on the board */
  92   ocd_write_bytes (watchdogaddr, nowatchdog, 4);
  93 }
  94
  95 /* Wait until the remote machine stops, then return,
  96    storing status in STATUS just as `wait' would.
  97    Returns "pid" (though it's not clear what, if anything, that
  98    means in the case of this target).  */
  99
 100 static int
 101 bdm_ppc_wait (pid, target_status)
 102      int pid;
 103      struct target_waitstatus *target_status;
 104 {
 105   int stop_reason;
 106
 107   target_status->kind = TARGET_WAITKIND_STOPPED;
 108
 109   stop_reason = ocd_wait ();
 110
 111   if (stop_reason)
 112     {
 113       target_status->value.sig = TARGET_SIGNAL_INT;
 114       return inferior_pid;
 115     }
 116
 117   target_status->value.sig = TARGET_SIGNAL_TRAP; /* XXX for now */
 118
 119 #if 0
 120   {
 121     unsigned long ecr, der;
 122
 123     ecr = ocd_read_bdm_register (148); /* Read the exception cause register */
 124     der = ocd_read_bdm_register (149); /* Read the debug enables register */
 125     fprintf_unfiltered (gdb_stdout, "ecr = 0x%x, der = 0x%x\n", ecr, der);
 126   }
 127 #endif
 128
 129   return inferior_pid;
 130 }
 131 \f
 132 static int bdm_regmap[] = {BDM_REGMAP};
 133
 134 /* Read the remote registers into regs.
 135    Fetch register REGNO, or all registers if REGNO == -1
 136
 137    The Wiggler uses the following codes to access the registers:
 138
 139    0 -> 1023            SPR 0 -> 1023
 140         0 - SPR 0 - MQ
 141         1 - SPR 1 - XER
 142         8 - SPR 8 - LR
 143         9 - SPR 9 - CTR (known as cnt in GDB)
 144         26 - SPR 26 - SRR0 - pc
 145    1024 -> 2047         DCR 0 -> DCR 1023 (IBM PPC 4xx only)
 146    2048 -> 2079         R0 -> R31
 147    2080 -> 2143         FP0 -> FP31 (64 bit regs) (IBM PPC 5xx only)
 148    2144                 CR (known as cnd in GDB)
 149    2145                 FPCSR
 150    2146                 MSR (known as ps in GDB)
 151  */
 152
 153 static void
 154 bdm_ppc_fetch_registers (regno)
 155      int regno;
 156 {
 157   int i;
 158   unsigned char *regs, *beginregs, *endregs, *almostregs;
 159   unsigned char midregs[32];
 160   unsigned char mqreg[1];
 161   int first_regno, last_regno;
 162   int first_bdm_regno, last_bdm_regno;
 163   int reglen, beginreglen, endreglen;
 164
 165 #if 1
 166   for (i = 0; i < (FPLAST_REGNUM - FP0_REGNUM + 1); i++)
 167     {
 168       midregs[i] = -1;
 169     }
 170   mqreg[0] = -1;
 171 #endif
 172
 173   if (regno == -1)
 174     {
 175       first_regno = 0;
 176       last_regno = NUM_REGS - 1;
 177
 178       first_bdm_regno = 0;
 179       last_bdm_regno = BDM_NUM_REGS - 1;
 180     }
 181   else
 182     {
 183       first_regno = regno;
 184       last_regno = regno;
 185
 186       first_bdm_regno = bdm_regmap [regno];
 187       last_bdm_regno = bdm_regmap [regno];
 188     }
 189
 190   if (first_bdm_regno == -1)
 191     {
 192       supply_register (first_regno, NULL);
 193       return;                   /* Unsupported register */
 194     }
 195
 196 #if 1
 197   /* Can't ask for floating point regs on ppc 8xx, also need to
 198      avoid asking for the mq register. */
 199   if (first_regno == last_regno)        /* only want one reg */
 200     {
 201 /*      printf("Asking for register %d\n", first_regno); */
 202
 203       /* if asking for an invalid register */
 204       if ((first_regno == MQ_REGNUM) ||
 205           ((first_regno >= FP0_REGNUM) && (first_regno <= FPLAST_REGNUM)))
 206         {
 207 /*          printf("invalid reg request!\n"); */
 208           supply_register (first_regno, NULL);
 209           return;                   /* Unsupported register */
 210         }
 211       else
 212         {
 213           regs = ocd_read_bdm_registers (first_bdm_regno,
 214                                                 last_bdm_regno, &reglen);
 215         }
 216     }
 217   else          /* want all regs */
 218     {
 219 /*      printf("Asking for registers %d to %d\n", first_regno, last_regno); */
 220       beginregs = ocd_read_bdm_registers (first_bdm_regno,
 221                                         FP0_REGNUM - 1, &beginreglen);
 222       endregs = (strcat (midregs,
 223                                 ocd_read_bdm_registers (FPLAST_REGNUM + 1,
 224                                         last_bdm_regno - 1, &endreglen)));
 225       almostregs = (strcat (beginregs, endregs));
 226       regs = (strcat (almostregs, mqreg));
 227       reglen = beginreglen + 32 + endreglen + 1;
 228     }
 229
 230 #endif
 231 #if 0
 232   regs = ocd_read_bdm_registers (first_bdm_regno, last_bdm_regno, &reglen);
 233 #endif
 234
 235   for (i = first_regno; i <= last_regno; i++)
 236     {
 237       int bdm_regno, regoffset;
 238
 239       bdm_regno = bdm_regmap [i];
 240       if (bdm_regno != -1)
 241         {
 242           regoffset = bdm_regno - first_bdm_regno;
 243
 244           if (regoffset >= reglen / 4)
 245             continue;
 246
 247           supply_register (i, regs + 4 * regoffset);
 248         }
 249       else
 250         supply_register (i, NULL); /* Unsupported register */
 251     }
 252 }
 253
 254 /* Store register REGNO, or all registers if REGNO == -1, from the contents
 255    of REGISTERS.  FIXME: ignores errors.  */
 256
 257 static void
 258 bdm_ppc_store_registers (regno)
 259      int regno;
 260 {
 261   int i;
 262   int first_regno, last_regno;
 263   int first_bdm_regno, last_bdm_regno;
 264
 265   if (regno == -1)
 266     {
 267       first_regno = 0;
 268       last_regno = NUM_REGS - 1;
 269
 270       first_bdm_regno = 0;
 271       last_bdm_regno = BDM_NUM_REGS - 1;
 272     }
 273   else
 274     {
 275       first_regno = regno;
 276       last_regno = regno;
 277
 278       first_bdm_regno = bdm_regmap [regno];
 279       last_bdm_regno = bdm_regmap [regno];
 280     }
 281
 282   if (first_bdm_regno == -1)
 283     return;                     /* Unsupported register */
 284
 285   for (i = first_regno; i <= last_regno; i++)
 286     {
 287       int bdm_regno;
 288
 289       bdm_regno = bdm_regmap [i];
 290
 291       /* only attempt to write if it's a valid ppc 8xx register */
 292       /* (need to avoid FP regs and MQ reg) */
 293       if ((i != MQ_REGNUM) && ((i < FP0_REGNUM) || (i > FPLAST_REGNUM)))
 294         {
 295 /*          printf("write valid reg %d\n", bdm_regno); */
 296           ocd_write_bdm_registers (bdm_regno, registers + REGISTER_BYTE (i), 4);
 297         }
 298 /*
 299       else if (i == MQ_REGNUM)
 300         printf("don't write invalid reg %d (MQ_REGNUM)\n", bdm_regno);
 301       else
 302         printf("don't write invalid reg %d\n", bdm_regno);
 303 */
 304     }
 305 }
 306 \f
 307 /* Define the target subroutine names */
 308
 309 struct target_ops bdm_ppc_ops = {
 310   "ocd",                        /* to_shortname */
 311   "Remote target with On-Chip Debugging",       /* to_longname */
 312   "Use a remote target with On-Chip Debugging.  To use a target box,\n\
 313 specify the serial device it is connected to (e.g. /dev/ttya).  To use\n\
 314 a wiggler, specify wiggler and then the port it is connected to\n\
 315 (e.g. wiggler lpt1).",  /* to_doc */
 316   bdm_ppc_open,                 /* to_open */
 317   ocd_close,            /* to_close */
 318   NULL,                         /* to_attach */
 319   ocd_detach,           /* to_detach */
 320   ocd_resume,           /* to_resume */
 321   bdm_ppc_wait,                 /* to_wait */
 322   bdm_ppc_fetch_registers,      /* to_fetch_registers */
 323   bdm_ppc_store_registers,      /* to_store_registers */
 324   ocd_prepare_to_store, /* to_prepare_to_store */
 325   ocd_xfer_memory,              /* to_xfer_memory */
 326   ocd_files_info,               /* to_files_info */
 327   ocd_insert_breakpoint,        /* to_insert_breakpoint */
 328   ocd_remove_breakpoint,        /* to_remove_breakpoint */
 329   NULL,                         /* to_terminal_init */
 330   NULL,                         /* to_terminal_inferior */
 331   NULL,                         /* to_terminal_ours_for_output */
 332   NULL,                         /* to_terminal_ours */
 333   NULL,                         /* to_terminal_info */
 334   ocd_kill,                     /* to_kill */
 335   ocd_load,                     /* to_load */
 336   NULL,                         /* to_lookup_symbol */
 337   ocd_create_inferior,  /* to_create_inferior */
 338   ocd_mourn,            /* to_mourn_inferior */
 339   0,                            /* to_can_run */
 340   0,                            /* to_notice_signals */
 341   ocd_thread_alive,             /* to_thread_alive */
 342   ocd_stop,                     /* to_stop */
 343   process_stratum,              /* to_stratum */
 344   NULL,                         /* to_next */
 345   1,                            /* to_has_all_memory */
 346   1,                            /* to_has_memory */
 347   1,                            /* to_has_stack */
 348   1,                            /* to_has_registers */
 349   1,                            /* to_has_execution */
 350   NULL,                         /* sections */
 351   NULL,                         /* sections_end */
 352   OPS_MAGIC                     /* to_magic */
 353 };
 354
 355 void
 356 _initialize_bdm_ppc ()
 357 {
 358   add_target (&bdm_ppc_ops);
 359 }