arch/ppc/cpu/mpc5xxx/traps.c

   1 /*
   2  * linux/arch/ppc/kernel/traps.c
   3  *
   4  * Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
   5  *
   6  * Modified by Cort Dougan (cort@cs.nmt.edu)
   7  * and Paul Mackerras (paulus@cs.anu.edu.au)
   8  * fixed Machine Check Reasons by Reinhard Meyer (r.meyer@emk-elektronik.de)
   9  *
  10  * (C) Copyright 2000-2003
  11  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  12  *
  13  * See file CREDITS for list of people who contributed to this
  14  * project.
  15  *
  16  * This program is free software; you can redistribute it and/or
  17  * modify it under the terms of the GNU General Public License as
  18  * published by the Free Software Foundation; either version 2 of
  19  * the License, or (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  29  * MA 02111-1307 USA
  30  */
  31
  32 /*
  33  * This file handles the architecture-dependent parts of hardware exceptions
  34  */
  35
  36 #include <common.h>
  37 #include <command.h>
  38 #include <kgdb.h>
  39 #include <asm/processor.h>
  40
  41 /* Returns 0 if exception not found and fixup otherwise.  */
  42 extern unsigned long search_exception_table(unsigned long);
  43
  44 /* THIS NEEDS CHANGING to use the board info structure.
  45 */
  46 #define END_OF_MEM      0x02000000
  47
  48 /*
  49  * Trap & Exception support
  50  */
  51
  52 void
  53 print_backtrace(unsigned long *sp)
  54 {
  55         int cnt = 0;
  56         unsigned long i;
  57
  58         printf("Call backtrace: ");
  59         while (sp) {
  60                 if ((uint)sp > END_OF_MEM)
  61                         break;
  62
  63                 i = sp[1];
  64                 if (cnt++ % 7 == 0)
  65                         printf("\n");
  66                 printf("%08lX ", i);
  67                 if (cnt > 32) break;
  68                 sp = (unsigned long *)*sp;
  69         }
  70         printf("\n");
  71 }
  72
  73 void show_regs(struct pt_regs * regs)
  74 {
  75         int i;
  76
  77         printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
  78                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  79         printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
  80                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  81                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  82                regs->msr&MSR_IR ? 1 : 0,
  83                regs->msr&MSR_DR ? 1 : 0);
  84
  85         printf("\n");
  86         for (i = 0;  i < 32;  i++) {
  87                 if ((i % 8) == 0)
  88                 {
  89                         printf("GPR%02d: ", i);
  90                 }
  91
  92                 printf("%08lX ", regs->gpr[i]);
  93                 if ((i % 8) == 7)
  94                 {
  95                         printf("\n");
  96                 }
  97         }
  98 }
  99
 100
 101 void
 102 _exception(int signr, struct pt_regs *regs)
 103 {
 104         show_regs(regs);
 105         print_backtrace((unsigned long *)regs->gpr[1]);
 106         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
 107 }
 108
 109 void
 110 MachineCheckException(struct pt_regs *regs)
 111 {
 112         unsigned long fixup;
 113
 114         /* Probing PCI using config cycles cause this exception
 115          * when a device is not present.  Catch it and return to
 116          * the PCI exception handler.
 117          */
 118         if ((fixup = search_exception_table(regs->nip)) != 0) {
 119                 regs->nip = fixup;
 120                 return;
 121         }
 122
 123 #if defined(CONFIG_CMD_KGDB)
 124         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 125                 return;
 126 #endif
 127
 128         printf("Machine check in kernel mode.\n");
 129         printf("Caused by (from msr): ");
 130         printf("regs %p ",regs);
 131         /* refer to 603e Manual (MPC603EUM/AD), chapter 4.5.2.1 */
 132         switch( regs->msr & 0x000F0000)
 133         {
 134         case (0x80000000>>12) :
 135                 printf("Machine check signal - probably due to mm fault\n"
 136                         "with mmu off\n");
 137                 break;
 138         case (0x80000000>>13) :
 139                 printf("Transfer error ack signal\n");
 140                 break;
 141         case (0x80000000>>14) :
 142                 printf("Data parity signal\n");
 143                 break;
 144         case (0x80000000>>15) :
 145                 printf("Address parity signal\n");
 146                 break;
 147         default:
 148                 printf("Unknown values in msr\n");
 149         }
 150         show_regs(regs);
 151         print_backtrace((unsigned long *)regs->gpr[1]);
 152         panic("machine check");
 153 }
 154
 155 void
 156 AlignmentException(struct pt_regs *regs)
 157 {
 158 #if defined(CONFIG_CMD_KGDB)
 159         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 160                 return;
 161 #endif
 162         show_regs(regs);
 163         print_backtrace((unsigned long *)regs->gpr[1]);
 164         panic("Alignment Exception");
 165 }
 166
 167 void
 168 ProgramCheckException(struct pt_regs *regs)
 169 {
 170 #if defined(CONFIG_CMD_KGDB)
 171         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 172                 return;
 173 #endif
 174         show_regs(regs);
 175         print_backtrace((unsigned long *)regs->gpr[1]);
 176         panic("Program Check Exception");
 177 }
 178
 179 void
 180 SoftEmuException(struct pt_regs *regs)
 181 {
 182 #if defined(CONFIG_CMD_KGDB)
 183         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 184                 return;
 185 #endif
 186         show_regs(regs);
 187         print_backtrace((unsigned long *)regs->gpr[1]);
 188         panic("Software Emulation Exception");
 189 }
 190
 191
 192 void
 193 UnknownException(struct pt_regs *regs)
 194 {
 195 #if defined(CONFIG_CMD_KGDB)
 196         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 197                 return;
 198 #endif
 199         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 200                regs->nip, regs->msr, regs->trap);
 201         _exception(0, regs);
 202 }
 203
 204 #if defined(CONFIG_CMD_BEDBUG)
 205 extern void do_bedbug_breakpoint(struct pt_regs *);
 206 #endif
 207
 208 void
 209 DebugException(struct pt_regs *regs)
 210 {
 211
 212   printf("Debugger trap at @ %lx\n", regs->nip );
 213   show_regs(regs);
 214 #if defined(CONFIG_CMD_BEDBUG)
 215   do_bedbug_breakpoint( regs );
 216 #endif
 217 }
 218
 219 /* Probe an address by reading.  If not present, return -1, otherwise
 220  * return 0.
 221  */
 222 int
 223 addr_probe(uint *addr)
 224 {
 225 #if 0
 226         int     retval;
 227
 228         __asm__ __volatile__(                   \
 229                 "1:     lwz %0,0(%1)\n"         \
 230                 "       eieio\n"                \
 231                 "       li %0,0\n"              \
 232                 "2:\n"                          \
 233                 ".section .fixup,\"ax\"\n"      \
 234                 "3:     li %0,-1\n"             \
 235                 "       b 2b\n"                 \
 236                 ".section __ex_table,\"a\"\n"   \
 237                 "       .align 2\n"             \
 238                 "       .long 1b,3b\n"          \
 239                 ".text"                         \
 240                 : "=r" (retval) : "r"(addr));
 241
 242         return (retval);
 243 #endif
 244         return 0;
 245 }