cpu/mpc86xx/traps.c

   1 /*
   2  * Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
   3  *
   4  * Modified by Cort Dougan (cort@cs.nmt.edu)
   5  * and Paul Mackerras (paulus@cs.anu.edu.au)
   6  *
   7  * (C) Copyright 2000
   8  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   9  *
  10  * See file CREDITS for list of people who contributed to this
  11  * project.
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License as
  15  * published by the Free Software Foundation; either version 2 of
  16  * the License, or (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  26  * MA 02111-1307 USA
  27  */
  28
  29 /*
  30  * This file handles the architecture-dependent parts of hardware exceptions
  31  */
  32
  33 #include <common.h>
  34 #include <command.h>
  35 #include <asm/processor.h>
  36
  37 #if defined(CONFIG_CMD_KGDB)
  38 int (*debugger_exception_handler)(struct pt_regs *) = 0;
  39 #endif
  40
  41 /* Returns 0 if exception not found and fixup otherwise.  */
  42 extern unsigned long search_exception_table(unsigned long);
  43
  44 #define END_OF_MEM (gd->bd->bi_memstart + gd->bd->bi_memsize)
  45
  46 /*
  47  * Trap & Exception support
  48  */
  49
  50 void
  51 print_backtrace(unsigned long *sp)
  52 {
  53         DECLARE_GLOBAL_DATA_PTR;
  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)
  68                         break;
  69                 sp = (unsigned long *)*sp;
  70         }
  71         printf("\n");
  72 }
  73
  74 void
  75 show_regs(struct pt_regs *regs)
  76 {
  77         int i;
  78
  79         printf("NIP: %08lX XER: %08lX LR: %08lX REGS:"
  80                " %p TRAP: %04lx DAR: %08lX\n",
  81                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  82         printf("MSR: %08lx EE: %01x PR: %01x FP:"
  83                " %01x ME: %01x IR/DR: %01x%01x\n",
  84                regs->msr, regs->msr & MSR_EE ? 1 : 0,
  85                regs->msr & MSR_PR ? 1 : 0, regs->msr & MSR_FP ? 1 : 0,
  86                regs->msr & MSR_ME ? 1 : 0, 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                         printf("GPR%02d: ", i);
  93                 }
  94
  95                 printf("%08lX ", regs->gpr[i]);
  96                 if ((i % 8) == 7) {
  97                         printf("\n");
  98                 }
  99         }
 100 }
 101
 102
 103 void
 104 _exception(int signr, struct pt_regs *regs)
 105 {
 106         show_regs(regs);
 107         print_backtrace((unsigned long *)regs->gpr[1]);
 108         panic("Exception in kernel pc %lx signal %d", regs->nip, signr);
 109 }
 110
 111 void
 112 MachineCheckException(struct pt_regs *regs)
 113 {
 114         unsigned long fixup;
 115
 116         /* Probing PCI using config cycles cause this exception
 117          * when a device is not present.  Catch it and return to
 118          * the PCI exception handler.
 119          */
 120         if ((fixup = search_exception_table(regs->nip)) != 0) {
 121                 regs->nip = fixup;
 122                 return;
 123         }
 124
 125 #if defined(CONFIG_CMD_KGDB)
 126         if (debugger_exception_handler && (*debugger_exception_handler) (regs))
 127                 return;
 128 #endif
 129
 130         printf("Machine check in kernel mode.\n");
 131         printf("Caused by (from msr): ");
 132         printf("regs %p ", regs);
 133         switch (regs->msr & 0x000F0000) {
 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         unsigned char *p = regs ? (unsigned char *)(regs->nip) : NULL;
 171         int i, j;
 172
 173 #if defined(CONFIG_CMD_KGDB)
 174         if (debugger_exception_handler && (*debugger_exception_handler) (regs))
 175                 return;
 176 #endif
 177         show_regs(regs);
 178
 179         p = (unsigned char *)((unsigned long)p & 0xFFFFFFE0);
 180         p -= 32;
 181         for (i = 0; i < 256; i += 16) {
 182                 printf("%08x: ", (unsigned int)p + i);
 183                 for (j = 0; j < 16; j++) {
 184                         printf("%02x ", p[i + j]);
 185                 }
 186                 printf("\n");
 187         }
 188
 189         print_backtrace((unsigned long *)regs->gpr[1]);
 190         panic("Program Check Exception");
 191 }
 192
 193 void
 194 SoftEmuException(struct pt_regs *regs)
 195 {
 196 #if defined(CONFIG_CMD_KGDB)
 197         if (debugger_exception_handler && (*debugger_exception_handler) (regs))
 198                 return;
 199 #endif
 200         show_regs(regs);
 201         print_backtrace((unsigned long *)regs->gpr[1]);
 202         panic("Software Emulation Exception");
 203 }
 204
 205 void
 206 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  * Probe an address by reading.
 219  * If not present, return -1,
 220  * otherwise return 0.
 221  */
 222 int
 223 addr_probe(uint *addr)
 224 {
 225         return 0;
 226 }