cpu/mpc85xx/traps.c

   1 /*
   2  * linux/arch/ppc/kernel/traps.c
   3  *
   4  * Copyright (C) 2003 Motorola
   5  * Modified by Xianghua Xiao(x.xiao@motorola.com)
   6  *
   7  * Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
   8  *
   9  * Modified by Cort Dougan (cort@cs.nmt.edu)
  10  * and Paul Mackerras (paulus@cs.anu.edu.au)
  11  *
  12  * (C) Copyright 2000
  13  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  14  *
  15  * See file CREDITS for list of people who contributed to this
  16  * project.
  17  *
  18  * This program is free software; you can redistribute it and/or
  19  * modify it under the terms of the GNU General Public License as
  20  * published by the Free Software Foundation; either version 2 of
  21  * the License, or (at your option) any later version.
  22  *
  23  * This program is distributed in the hope that it will be useful,
  24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  * GNU General Public License for more details.
  27  *
  28  * You should have received a copy of the GNU General Public License
  29  * along with this program; if not, write to the Free Software
  30  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  31  * MA 02111-1307 USA
  32  */
  33
  34 /*
  35  * This file handles the architecture-dependent parts of hardware exceptions
  36  */
  37
  38 #include <common.h>
  39 #include <command.h>
  40 #include <asm/processor.h>
  41
  42 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
  43 int (*debugger_exception_handler)(struct pt_regs *) = 0;
  44 #endif
  45
  46 /* Returns 0 if exception not found and fixup otherwise.  */
  47 extern unsigned long search_exception_table(unsigned long);
  48
  49 /*
  50  * End of memory as shown by board info and determined by DDR setup.
  51  */
  52 #define END_OF_MEM      (gd->bd->bi_memstart + gd->bd->bi_memsize)
  53
  54
  55 static __inline__ void set_tsr(unsigned long val)
  56 {
  57         asm volatile("mtspr 0x150, %0" : : "r" (val));
  58 }
  59
  60 static __inline__ unsigned long get_esr(void)
  61 {
  62         unsigned long val;
  63         asm volatile("mfspr %0, 0x03e" : "=r" (val) :);
  64         return val;
  65 }
  66
  67 #define ESR_MCI 0x80000000
  68 #define ESR_PIL 0x08000000
  69 #define ESR_PPR 0x04000000
  70 #define ESR_PTR 0x02000000
  71 #define ESR_DST 0x00800000
  72 #define ESR_DIZ 0x00400000
  73 #define ESR_U0F 0x00008000
  74
  75 #if (CONFIG_COMMANDS & CFG_CMD_BEDBUG)
  76 extern void do_bedbug_breakpoint(struct pt_regs *);
  77 #endif
  78
  79 /*
  80  * Trap & Exception support
  81  */
  82
  83 void
  84 print_backtrace(unsigned long *sp)
  85 {
  86         DECLARE_GLOBAL_DATA_PTR;
  87         int cnt = 0;
  88         unsigned long i;
  89
  90         printf("Call backtrace: ");
  91         while (sp) {
  92                 if ((uint)sp > END_OF_MEM)
  93                         break;
  94
  95                 i = sp[1];
  96                 if (cnt++ % 7 == 0)
  97                         printf("\n");
  98                 printf("%08lX ", i);
  99                 if (cnt > 32) break;
 100                 sp = (unsigned long *)*sp;
 101         }
 102         printf("\n");
 103 }
 104
 105 void show_regs(struct pt_regs * regs)
 106 {
 107         int i;
 108
 109         printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
 110                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
 111         printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
 112                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
 113                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
 114                regs->msr&MSR_IR ? 1 : 0,
 115                regs->msr&MSR_DR ? 1 : 0);
 116
 117         printf("\n");
 118         for (i = 0;  i < 32;  i++) {
 119                 if ((i % 8) == 0)
 120                 {
 121                         printf("GPR%02d: ", i);
 122                 }
 123
 124                 printf("%08lX ", regs->gpr[i]);
 125                 if ((i % 8) == 7)
 126                 {
 127                         printf("\n");
 128                 }
 129         }
 130 }
 131
 132
 133 void
 134 _exception(int signr, struct pt_regs *regs)
 135 {
 136         show_regs(regs);
 137         print_backtrace((unsigned long *)regs->gpr[1]);
 138         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
 139 }
 140
 141 void
 142 CritcalInputException(struct pt_regs *regs)
 143 {
 144         panic("Critical Input Exception");
 145 }
 146
 147 void
 148 MachineCheckException(struct pt_regs *regs)
 149 {
 150         unsigned long fixup;
 151
 152         /* Probing PCI using config cycles cause this exception
 153          * when a device is not present.  Catch it and return to
 154          * the PCI exception handler.
 155          */
 156         if ((fixup = search_exception_table(regs->nip)) != 0) {
 157                 regs->nip = fixup;
 158                 return;
 159         }
 160
 161 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
 162         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 163                 return;
 164 #endif
 165
 166         printf("Machine check in kernel mode.\n");
 167         printf("Caused by (from msr): ");
 168         printf("regs %p ",regs);
 169         switch( regs->msr & 0x000F0000) {
 170         case (0x80000000>>12):
 171                 printf("Machine check signal - probably due to mm fault\n"
 172                        "with mmu off\n");
 173                 break;
 174         case (0x80000000>>13):
 175                 printf("Transfer error ack signal\n");
 176                 break;
 177         case (0x80000000>>14):
 178                 printf("Data parity signal\n");
 179                 break;
 180         case (0x80000000>>15):
 181                 printf("Address parity signal\n");
 182                 break;
 183         default:
 184                 printf("Unknown values in msr\n");
 185         }
 186         show_regs(regs);
 187         print_backtrace((unsigned long *)regs->gpr[1]);
 188         panic("machine check");
 189 }
 190
 191 void
 192 AlignmentException(struct pt_regs *regs)
 193 {
 194 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
 195         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 196                 return;
 197 #endif
 198
 199         show_regs(regs);
 200         print_backtrace((unsigned long *)regs->gpr[1]);
 201         panic("Alignment Exception");
 202 }
 203
 204 void
 205 ProgramCheckException(struct pt_regs *regs)
 206 {
 207         long esr_val;
 208
 209 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
 210         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 211                 return;
 212 #endif
 213
 214         show_regs(regs);
 215
 216         esr_val = get_esr();
 217         if( esr_val & ESR_PIL )
 218                 printf( "** Illegal Instruction **\n" );
 219         else if( esr_val & ESR_PPR )
 220                 printf( "** Privileged Instruction **\n" );
 221         else if( esr_val & ESR_PTR )
 222                 printf( "** Trap Instruction **\n" );
 223
 224         print_backtrace((unsigned long *)regs->gpr[1]);
 225         panic("Program Check Exception");
 226 }
 227
 228 void
 229 PITException(struct pt_regs *regs)
 230 {
 231         /*
 232          * Reset PIT interrupt
 233          */
 234         set_tsr(0x0c000000);
 235
 236         /*
 237          * Call timer_interrupt routine in interrupts.c
 238          */
 239         timer_interrupt(NULL);
 240 }
 241
 242
 243 void
 244 UnknownException(struct pt_regs *regs)
 245 {
 246 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
 247         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 248                 return;
 249 #endif
 250
 251         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 252                regs->nip, regs->msr, regs->trap);
 253         _exception(0, regs);
 254 }
 255
 256 void
 257 DebugException(struct pt_regs *regs)
 258 {
 259         printf("Debugger trap at @ %lx\n", regs->nip );
 260         show_regs(regs);
 261 #if (CONFIG_COMMANDS & CFG_CMD_BEDBUG)
 262         do_bedbug_breakpoint( regs );
 263 #endif
 264 }
 265
 266 /* Probe an address by reading.  If not present, return -1, otherwise
 267  * return 0.
 268  */
 269 int
 270 addr_probe(uint *addr)
 271 {
 272         return 0;
 273 }