arch/powerpc/cpu/mpc5xx/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  *
   9  * (C) Copyright 2000
  10  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  11  *
  12  * See file CREDITS for list of people who contributed to this
  13  * project.
  14  *
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License as
  17  * published by the Free Software Foundation; either version 2 of
  18  * the License, or (at your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  * GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with this program; if not, write to the Free Software
  27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  28  * MA 02111-1307 USA
  29  */
  30
  31 /*
  32  * This file handles the architecture-dependent parts of hardware exceptions
  33  */
  34
  35 #include <common.h>
  36 #include <command.h>
  37 #include <kgdb.h>
  38 #include <asm/processor.h>
  39
  40 #if defined(CONFIG_CMD_BEDBUG)
  41 extern void do_bedbug_breakpoint(struct pt_regs *);
  42 #endif
  43
  44 /* Returns 0 if exception not found and fixup otherwise.  */
  45 extern unsigned long search_exception_table(unsigned long);
  46
  47 /* THIS NEEDS CHANGING to use the board info structure.
  48 */
  49 #define END_OF_MEM      0x0001000
  50
  51
  52 /*
  53  * Print stack backtrace
  54  */
  55 static void print_backtrace(unsigned long *sp)
  56 {
  57         int cnt = 0;
  58         unsigned long i;
  59
  60         printf("Call backtrace: ");
  61         while (sp) {
  62                 if ((uint)sp > END_OF_MEM)
  63                         break;
  64
  65                 i = sp[1];
  66                 if (cnt++ % 7 == 0)
  67                         printf("\n");
  68                 printf("%08lX ", i);
  69                 if (cnt > 32) break;
  70                 sp = (unsigned long *)*sp;
  71         }
  72         printf("\n");
  73 }
  74
  75 /*
  76  * Print current registers
  77  */
  78 void show_regs(struct pt_regs *regs)
  79 {
  80         int i;
  81         printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
  82                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  83         printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
  84                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  85                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  86                regs->msr&MSR_IR ? 1 : 0,
  87                regs->msr&MSR_DR ? 1 : 0);
  88
  89         printf("\n");
  90         for (i = 0;  i < 32;  i++) {
  91                 if ((i % 8) == 0)
  92                 {
  93                         printf("GPR%02d: ", i);
  94                 }
  95
  96                 printf("%08lX ", regs->gpr[i]);
  97                 if ((i % 8) == 7)
  98                 {
  99                         printf("\n");
 100                 }
 101         }
 102 }
 103
 104
 105 /*
 106  * General exception handler routine
 107  */
 108 static void _exception(int signr, struct pt_regs *regs)
 109 {
 110         show_regs(regs);
 111         print_backtrace((unsigned long *)regs->gpr[1]);
 112         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
 113 }
 114
 115 /*
 116  * Machine check exception handler routine
 117  */
 118 void MachineCheckException(struct pt_regs *regs)
 119 {
 120         unsigned long fixup;
 121
 122         /* Probing PCI using config cycles cause this exception
 123          * when a device is not present.  Catch it and return to
 124          * the PCI exception handler.
 125          */
 126         if ((fixup = search_exception_table(regs->nip)) != 0) {
 127                 regs->nip = fixup;
 128                 return;
 129         }
 130
 131 #if defined(CONFIG_CMD_KGDB)
 132         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 133                 return;
 134 #endif
 135
 136         printf("Machine check in kernel mode.\n");
 137         printf("Caused by (from msr): ");
 138         printf("regs %p ",regs);
 139         switch( regs->msr & 0x000F0000) {
 140         case (0x80000000>>12):
 141                 printf("Machine check signal\n");
 142                 break;
 143         case (0x80000000>>13):
 144                 printf("Transfer error ack signal\n");
 145                 break;
 146         case (0x80000000>>14):
 147                 printf("Data parity signal\n");
 148                 break;
 149         case (0x80000000>>15):
 150                 printf("Address parity signal\n");
 151                 break;
 152         default:
 153                 printf("Unknown values in msr\n");
 154         }
 155         show_regs(regs);
 156         print_backtrace((unsigned long *)regs->gpr[1]);
 157         panic("machine check");
 158 }
 159
 160 /*
 161  * Alignment exception handler routine
 162  */
 163 void AlignmentException(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("Alignment Exception");
 172 }
 173
 174 /*
 175  * Program check exception handler routine
 176  */
 177 void ProgramCheckException(struct pt_regs *regs)
 178 {
 179 #if defined(CONFIG_CMD_KGDB)
 180         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 181                 return;
 182 #endif
 183         show_regs(regs);
 184         print_backtrace((unsigned long *)regs->gpr[1]);
 185         panic("Program Check Exception");
 186 }
 187
 188 /*
 189  * Software emulation exception handler routine
 190  */
 191 void SoftEmuException(struct pt_regs *regs)
 192 {
 193 #if defined(CONFIG_CMD_KGDB)
 194         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 195                 return;
 196 #endif
 197         show_regs(regs);
 198         print_backtrace((unsigned long *)regs->gpr[1]);
 199         panic("Software Emulation Exception");
 200 }
 201
 202
 203 /*
 204  * Unknown exception handler routine
 205  */
 206 void UnknownException(struct pt_regs *regs)
 207 {
 208 #if defined(CONFIG_CMD_KGDB)
 209         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 210                 return;
 211 #endif
 212         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 213                regs->nip, regs->msr, regs->trap);
 214         _exception(0, regs);
 215 }
 216
 217 /*
 218  * Debug exception handler routine
 219  */
 220 void DebugException(struct pt_regs *regs)
 221 {
 222         printf("Debugger trap at @ %lx\n", regs->nip );
 223         show_regs(regs);
 224 #if defined(CONFIG_CMD_BEDBUG)
 225         do_bedbug_breakpoint( regs );
 226 #endif
 227 }