cpu/74xx_7xx/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  *
   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 <asm/processor.h>
  38
  39 #ifdef CONFIG_AMIGAONEG3SE
  40 DECLARE_GLOBAL_DATA_PTR;
  41 #endif
  42
  43 #if defined(CONFIG_CMD_KGDB)
  44 int (*debugger_exception_handler)(struct pt_regs *) = 0;
  45 #endif
  46
  47 /* Returns 0 if exception not found and fixup otherwise.  */
  48 extern unsigned long search_exception_table(unsigned long);
  49
  50 /* THIS NEEDS CHANGING to use the board info structure.
  51 */
  52 #ifdef CONFIG_AMIGAONEG3SE
  53 #define END_OF_MEM (gd->bd->bi_memstart + gd->bd->bi_memsize)
  54 #else
  55 #define END_OF_MEM      0x02000000
  56 #endif
  57
  58 /*
  59  * Trap & Exception support
  60  */
  61
  62 void
  63 print_backtrace(unsigned long *sp)
  64 {
  65         int cnt = 0;
  66         unsigned long i;
  67
  68         printf("Call backtrace: ");
  69         while (sp) {
  70                 if ((uint)sp > END_OF_MEM)
  71                         break;
  72
  73                 i = sp[1];
  74                 if (cnt++ % 7 == 0)
  75                         printf("\n");
  76                 printf("%08lX ", i);
  77                 if (cnt > 32) break;
  78                 sp = (unsigned long *)*sp;
  79         }
  80         printf("\n");
  81 }
  82
  83 void
  84 show_regs(struct pt_regs * regs)
  85 {
  86         int i;
  87
  88         printf("NIP: %08lX XER: %08lX LR: %08lX REGS:"
  89                " %p TRAP: %04lx DAR: %08lX\n",
  90                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  91         printf("MSR: %08lx EE: %01x PR: %01x FP:"
  92                " %01x ME: %01x IR/DR: %01x%01x\n",
  93                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  94                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  95                regs->msr&MSR_IR ? 1 : 0,
  96                regs->msr&MSR_DR ? 1 : 0);
  97
  98         printf("\n");
  99         for (i = 0;  i < 32;  i++) {
 100                 if ((i % 8) == 0)
 101                 {
 102                         printf("GPR%02d: ", i);
 103                 }
 104
 105                 printf("%08lX ", regs->gpr[i]);
 106                 if ((i % 8) == 7)
 107                 {
 108                         printf("\n");
 109                 }
 110         }
 111 }
 112
 113
 114 void
 115 _exception(int signr, struct pt_regs *regs)
 116 {
 117         show_regs(regs);
 118         print_backtrace((unsigned long *)regs->gpr[1]);
 119         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
 120 }
 121
 122 void
 123 MachineCheckException(struct pt_regs *regs)
 124 {
 125         unsigned long fixup;
 126
 127         /* Probing PCI using config cycles cause this exception
 128          * when a device is not present.  Catch it and return to
 129          * the PCI exception handler.
 130          */
 131         if ((fixup = search_exception_table(regs->nip)) != 0) {
 132                 regs->nip = fixup;
 133                 return;
 134         }
 135
 136 #if defined(CONFIG_CMD_KGDB)
 137         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 138                 return;
 139 #endif
 140
 141         printf("Machine check in kernel mode.\n");
 142         printf("Caused by (from msr): ");
 143         printf("regs %p ",regs);
 144         switch( regs->msr & 0x000F0000) {
 145         case (0x80000000>>12):
 146                 printf("Machine check signal - probably due to mm fault\n"
 147                         "with mmu off\n");
 148                 break;
 149         case (0x80000000>>13):
 150                 printf("Transfer error ack signal\n");
 151                 break;
 152         case (0x80000000>>14):
 153                 printf("Data parity signal\n");
 154                 break;
 155         case (0x80000000>>15):
 156                 printf("Address parity signal\n");
 157                 break;
 158         default:
 159                 printf("Unknown values in msr\n");
 160         }
 161         show_regs(regs);
 162         print_backtrace((unsigned long *)regs->gpr[1]);
 163         panic("machine check");
 164 }
 165
 166 void
 167 AlignmentException(struct pt_regs *regs)
 168 {
 169 #if defined(CONFIG_CMD_KGDB)
 170         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 171                 return;
 172 #endif
 173         show_regs(regs);
 174         print_backtrace((unsigned long *)regs->gpr[1]);
 175         panic("Alignment Exception");
 176 }
 177
 178 void
 179 ProgramCheckException(struct pt_regs *regs)
 180 {
 181         unsigned char *p = regs ? (unsigned char *)(regs->nip) : NULL;
 182         int i, j;
 183
 184 #if defined(CONFIG_CMD_KGDB)
 185         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 186                 return;
 187 #endif
 188         show_regs(regs);
 189
 190         p = (unsigned char *) ((unsigned long)p & 0xFFFFFFE0);
 191         p -= 32;
 192         for (i = 0; i < 256; i+=16) {
 193                 printf("%08x: ", (unsigned int)p+i);
 194                 for (j = 0; j < 16; j++) {
 195                         printf("%02x ", p[i+j]);
 196                 }
 197                 printf("\n");
 198         }
 199
 200         print_backtrace((unsigned long *)regs->gpr[1]);
 201         panic("Program Check Exception");
 202 }
 203
 204 void
 205 SoftEmuException(struct pt_regs *regs)
 206 {
 207 #if defined(CONFIG_CMD_KGDB)
 208         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 209                 return;
 210 #endif
 211         show_regs(regs);
 212         print_backtrace((unsigned long *)regs->gpr[1]);
 213         panic("Software Emulation Exception");
 214 }
 215
 216
 217 void
 218 UnknownException(struct pt_regs *regs)
 219 {
 220 #if defined(CONFIG_CMD_KGDB)
 221         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 222                 return;
 223 #endif
 224         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 225                regs->nip, regs->msr, regs->trap);
 226         _exception(0, regs);
 227 }
 228
 229 /* Probe an address by reading.  If not present, return -1, otherwise
 230  * return 0.
 231  */
 232 int
 233 addr_probe(uint *addr)
 234 {
 235 #if 0
 236         int     retval;
 237
 238         __asm__ __volatile__(                   \
 239                 "1:     lwz %0,0(%1)\n"         \
 240                 "       eieio\n"                \
 241                 "       li %0,0\n"              \
 242                 "2:\n"                          \
 243                 ".section .fixup,\"ax\"\n"      \
 244                 "3:     li %0,-1\n"             \
 245                 "       b 2b\n"                 \
 246                 ".section __ex_table,\"a\"\n"   \
 247                 "       .align 2\n"             \
 248                 "       .long 1b,3b\n"          \
 249                 ".text"                         \
 250                 : "=r" (retval) : "r"(addr));
 251
 252         return (retval);
 253 #endif
 254         return 0;
 255 }