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