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