arch/powerpc/cpu/mpc5xxx/traps.c

   1 /*
   2  * linux/arch/powerpc/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 static void print_backtrace(unsigned long *sp)
  53 {
  54         int cnt = 0;
  55         unsigned long i;
  56
  57         printf("Call backtrace: ");
  58         while (sp) {
  59                 if ((uint)sp > END_OF_MEM)
  60                         break;
  61
  62                 i = sp[1];
  63                 if (cnt++ % 7 == 0)
  64                         printf("\n");
  65                 printf("%08lX ", i);
  66                 if (cnt > 32) break;
  67                 sp = (unsigned long *)*sp;
  68         }
  69         printf("\n");
  70 }
  71
  72 void show_regs(struct pt_regs *regs)
  73 {
  74         int i;
  75
  76         printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
  77                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  78         printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
  79                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  80                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  81                regs->msr&MSR_IR ? 1 : 0,
  82                regs->msr&MSR_DR ? 1 : 0);
  83
  84         printf("\n");
  85         for (i = 0;  i < 32;  i++) {
  86                 if ((i % 8) == 0)
  87                 {
  88                         printf("GPR%02d: ", i);
  89                 }
  90
  91                 printf("%08lX ", regs->gpr[i]);
  92                 if ((i % 8) == 7)
  93                 {
  94                         printf("\n");
  95                 }
  96         }
  97 }
  98
  99
 100 static void _exception(int signr, struct pt_regs *regs)
 101 {
 102         show_regs(regs);
 103         print_backtrace((unsigned long *)regs->gpr[1]);
 104         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
 105 }
 106
 107 void MachineCheckException(struct pt_regs *regs)
 108 {
 109         unsigned long fixup;
 110
 111         /* Probing PCI using config cycles cause this exception
 112          * when a device is not present.  Catch it and return to
 113          * the PCI exception handler.
 114          */
 115         if ((fixup = search_exception_table(regs->nip)) != 0) {
 116                 regs->nip = fixup;
 117                 return;
 118         }
 119
 120 #if defined(CONFIG_CMD_KGDB)
 121         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 122                 return;
 123 #endif
 124
 125         printf("Machine check in kernel mode.\n");
 126         printf("Caused by (from msr): ");
 127         printf("regs %p ",regs);
 128         /* refer to 603e Manual (MPC603EUM/AD), chapter 4.5.2.1 */
 129         switch( regs->msr & 0x000F0000)
 130         {
 131         case (0x80000000>>12) :
 132                 printf("Machine check signal - probably due to mm fault\n"
 133                         "with mmu off\n");
 134                 break;
 135         case (0x80000000>>13) :
 136                 printf("Transfer error ack signal\n");
 137                 break;
 138         case (0x80000000>>14) :
 139                 printf("Data parity signal\n");
 140                 break;
 141         case (0x80000000>>15) :
 142                 printf("Address parity signal\n");
 143                 break;
 144         default:
 145                 printf("Unknown values in msr\n");
 146         }
 147         show_regs(regs);
 148         print_backtrace((unsigned long *)regs->gpr[1]);
 149         panic("machine check");
 150 }
 151
 152 void AlignmentException(struct pt_regs *regs)
 153 {
 154 #if defined(CONFIG_CMD_KGDB)
 155         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 156                 return;
 157 #endif
 158         show_regs(regs);
 159         print_backtrace((unsigned long *)regs->gpr[1]);
 160         panic("Alignment Exception");
 161 }
 162
 163 void ProgramCheckException(struct pt_regs *regs)
 164 {
 165 #if defined(CONFIG_CMD_KGDB)
 166         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 167                 return;
 168 #endif
 169         show_regs(regs);
 170         print_backtrace((unsigned long *)regs->gpr[1]);
 171         panic("Program Check Exception");
 172 }
 173
 174 void SoftEmuException(struct pt_regs *regs)
 175 {
 176 #if defined(CONFIG_CMD_KGDB)
 177         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 178                 return;
 179 #endif
 180         show_regs(regs);
 181         print_backtrace((unsigned long *)regs->gpr[1]);
 182         panic("Software Emulation Exception");
 183 }
 184
 185
 186 void UnknownException(struct pt_regs *regs)
 187 {
 188 #if defined(CONFIG_CMD_KGDB)
 189         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 190                 return;
 191 #endif
 192         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 193                regs->nip, regs->msr, regs->trap);
 194         _exception(0, regs);
 195 }
 196
 197 #if defined(CONFIG_CMD_BEDBUG)
 198 extern void do_bedbug_breakpoint(struct pt_regs *);
 199 #endif
 200
 201 void DebugException(struct pt_regs *regs)
 202 {
 203
 204   printf("Debugger trap at @ %lx\n", regs->nip );
 205   show_regs(regs);
 206 #if defined(CONFIG_CMD_BEDBUG)
 207   do_bedbug_breakpoint( regs );
 208 #endif
 209 }
 210
 211 /* Probe an address by reading.  If not present, return -1, otherwise
 212  * return 0.
 213  */
 214 int addr_probe(uint *addr)
 215 {
 216 #if 0
 217         int     retval;
 218
 219         __asm__ __volatile__(                   \
 220                 "1:     lwz %0,0(%1)\n"         \
 221                 "       eieio\n"                \
 222                 "       li %0,0\n"              \
 223                 "2:\n"                          \
 224                 ".section .fixup,\"ax\"\n"      \
 225                 "3:     li %0,-1\n"             \
 226                 "       b 2b\n"                 \
 227                 ".section __ex_table,\"a\"\n"   \
 228                 "       .align 2\n"             \
 229                 "       .long 1b,3b\n"          \
 230                 ".text"                         \
 231                 : "=r" (retval) : "r"(addr));
 232
 233         return (retval);
 234 #endif
 235         return 0;
 236 }