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  * SPDX-License-Identifier:     GPL-2.0+
  13  */
  14
  15 /*
  16  * This file handles the architecture-dependent parts of hardware exceptions
  17  */
  18
  19 #include <common.h>
  20 #include <command.h>
  21 #include <kgdb.h>
  22 #include <asm/processor.h>
  23
  24 #if defined(CONFIG_CMD_BEDBUG)
  25 extern void do_bedbug_breakpoint(struct pt_regs *);
  26 #endif
  27
  28 /* Returns 0 if exception not found and fixup otherwise.  */
  29 extern unsigned long search_exception_table(unsigned long);
  30
  31 /* THIS NEEDS CHANGING to use the board info structure.
  32 */
  33 #define END_OF_MEM      0x0001000
  34
  35
  36 /*
  37  * Print stack backtrace
  38  */
  39 static void print_backtrace(unsigned long *sp)
  40 {
  41         int cnt = 0;
  42         unsigned long i;
  43
  44         printf("Call backtrace: ");
  45         while (sp) {
  46                 if ((uint)sp > END_OF_MEM)
  47                         break;
  48
  49                 i = sp[1];
  50                 if (cnt++ % 7 == 0)
  51                         printf("\n");
  52                 printf("%08lX ", i);
  53                 if (cnt > 32) break;
  54                 sp = (unsigned long *)*sp;
  55         }
  56         printf("\n");
  57 }
  58
  59 /*
  60  * Print current registers
  61  */
  62 void show_regs(struct pt_regs *regs)
  63 {
  64         int i;
  65         printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
  66                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  67         printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
  68                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  69                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  70                regs->msr&MSR_IR ? 1 : 0,
  71                regs->msr&MSR_DR ? 1 : 0);
  72
  73         printf("\n");
  74         for (i = 0;  i < 32;  i++) {
  75                 if ((i % 8) == 0)
  76                 {
  77                         printf("GPR%02d: ", i);
  78                 }
  79
  80                 printf("%08lX ", regs->gpr[i]);
  81                 if ((i % 8) == 7)
  82                 {
  83                         printf("\n");
  84                 }
  85         }
  86 }
  87
  88
  89 /*
  90  * General exception handler routine
  91  */
  92 static void _exception(int signr, struct pt_regs *regs)
  93 {
  94         show_regs(regs);
  95         print_backtrace((unsigned long *)regs->gpr[1]);
  96         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
  97 }
  98
  99 /*
 100  * Machine check exception handler routine
 101  */
 102 void MachineCheckException(struct pt_regs *regs)
 103 {
 104         unsigned long fixup;
 105
 106         /* Probing PCI using config cycles cause this exception
 107          * when a device is not present.  Catch it and return to
 108          * the PCI exception handler.
 109          */
 110         if ((fixup = search_exception_table(regs->nip)) != 0) {
 111                 regs->nip = fixup;
 112                 return;
 113         }
 114
 115 #if defined(CONFIG_CMD_KGDB)
 116         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 117                 return;
 118 #endif
 119
 120         printf("Machine check in kernel mode.\n");
 121         printf("Caused by (from msr): ");
 122         printf("regs %p ",regs);
 123         switch( regs->msr & 0x000F0000) {
 124         case (0x80000000>>12):
 125                 printf("Machine check signal\n");
 126                 break;
 127         case (0x80000000>>13):
 128                 printf("Transfer error ack signal\n");
 129                 break;
 130         case (0x80000000>>14):
 131                 printf("Data parity signal\n");
 132                 break;
 133         case (0x80000000>>15):
 134                 printf("Address parity signal\n");
 135                 break;
 136         default:
 137                 printf("Unknown values in msr\n");
 138         }
 139         show_regs(regs);
 140         print_backtrace((unsigned long *)regs->gpr[1]);
 141         panic("machine check");
 142 }
 143
 144 /*
 145  * Alignment exception handler routine
 146  */
 147 void AlignmentException(struct pt_regs *regs)
 148 {
 149 #if defined(CONFIG_CMD_KGDB)
 150         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 151                 return;
 152 #endif
 153         show_regs(regs);
 154         print_backtrace((unsigned long *)regs->gpr[1]);
 155         panic("Alignment Exception");
 156 }
 157
 158 /*
 159  * Program check exception handler routine
 160  */
 161 void ProgramCheckException(struct pt_regs *regs)
 162 {
 163 #if defined(CONFIG_CMD_KGDB)
 164         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 165                 return;
 166 #endif
 167         show_regs(regs);
 168         print_backtrace((unsigned long *)regs->gpr[1]);
 169         panic("Program Check Exception");
 170 }
 171
 172 /*
 173  * Software emulation exception handler routine
 174  */
 175 void SoftEmuException(struct pt_regs *regs)
 176 {
 177 #if defined(CONFIG_CMD_KGDB)
 178         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 179                 return;
 180 #endif
 181         show_regs(regs);
 182         print_backtrace((unsigned long *)regs->gpr[1]);
 183         panic("Software Emulation Exception");
 184 }
 185
 186
 187 /*
 188  * Unknown exception handler routine
 189  */
 190 void UnknownException(struct pt_regs *regs)
 191 {
 192 #if defined(CONFIG_CMD_KGDB)
 193         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 194                 return;
 195 #endif
 196         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 197                regs->nip, regs->msr, regs->trap);
 198         _exception(0, regs);
 199 }
 200
 201 /*
 202  * Debug exception handler routine
 203  */
 204 void DebugException(struct pt_regs *regs)
 205 {
 206         printf("Debugger trap at @ %lx\n", regs->nip );
 207         show_regs(regs);
 208 #if defined(CONFIG_CMD_BEDBUG)
 209         do_bedbug_breakpoint( regs );
 210 #endif
 211 }