arch/ppc/cpu/mpc8260/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 <kgdb.h>
  38 #include <asm/processor.h>
  39 #include <asm/m8260_pci.h>
  40
  41 /* Returns 0 if exception not found and fixup otherwise.  */
  42 extern unsigned long search_exception_table(unsigned long);
  43
  44 /* THIS NEEDS CHANGING to use the board info structure.
  45 */
  46 #define END_OF_MEM      0x02000000
  47
  48 /*
  49  * Trap & Exception support
  50  */
  51
  52 void
  53 print_backtrace(unsigned long *sp)
  54 {
  55         int cnt = 0;
  56         unsigned long i;
  57
  58         puts ("Call backtrace: ");
  59         while (sp) {
  60                 if ((uint)sp > END_OF_MEM)
  61                         break;
  62
  63                 i = sp[1];
  64                 if (cnt++ % 7 == 0)
  65                         putc ('\n');
  66                 printf("%08lX ", i);
  67                 if (cnt > 32) break;
  68                 sp = (unsigned long *)*sp;
  69         }
  70         putc ('\n');
  71 }
  72
  73 void show_regs(struct pt_regs * regs)
  74 {
  75         int i;
  76
  77         printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
  78                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  79         printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
  80                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  81                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  82                regs->msr&MSR_IR ? 1 : 0,
  83                regs->msr&MSR_DR ? 1 : 0);
  84
  85         putc ('\n');
  86         for (i = 0;  i < 32;  i++) {
  87                 if ((i % 8) == 0) {
  88                         printf("GPR%02d: ", i);
  89                 }
  90
  91                 printf("%08lX ", regs->gpr[i]);
  92                 if ((i % 8) == 7) {
  93                         putc ('\n');
  94                 }
  95         }
  96 }
  97
  98
  99 void
 100 _exception(int signr, struct pt_regs *regs)
 101 {
 102         show_regs(regs);
 103         print_backtrace((unsigned long *)regs->gpr[1]);
 104         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
 105 }
 106
 107 #ifdef CONFIG_PCI
 108 void dump_pci (void)
 109 {
 110
 111         volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 112
 113         printf ("PCI: err status %x err mask %x err ctrl %x\n",
 114                 le32_to_cpu (immap->im_pci.pci_esr),
 115                 le32_to_cpu (immap->im_pci.pci_emr),
 116                 le32_to_cpu (immap->im_pci.pci_ecr));
 117         printf ("     error address %x error data %x ctrl %x\n",
 118                 le32_to_cpu (immap->im_pci.pci_eacr),
 119                 le32_to_cpu (immap->im_pci.pci_edcr),
 120                 le32_to_cpu (immap->im_pci.pci_eccr));
 121
 122 }
 123 #endif
 124
 125 void
 126 MachineCheckException(struct pt_regs *regs)
 127 {
 128         unsigned long fixup;
 129
 130         /* Probing PCI using config cycles cause this exception
 131          * when a device is not present.  Catch it and return to
 132          * the PCI exception handler.
 133          */
 134 #ifdef CONFIG_PCI
 135         volatile immap_t *immap  = (immap_t *)CONFIG_SYS_IMMR;
 136 #ifdef DEBUG
 137         dump_pci();
 138 #endif
 139         /* clear the error in the error status register */
 140         if(immap->im_pci.pci_esr & cpu_to_le32(PCI_ERROR_PCI_NO_RSP)) {
 141                 immap->im_pci.pci_esr = cpu_to_le32(PCI_ERROR_PCI_NO_RSP);
 142                 return;
 143         }
 144 #endif
 145         if ((fixup = search_exception_table(regs->nip)) != 0) {
 146                 regs->nip = fixup;
 147                 return;
 148         }
 149
 150 #if defined(CONFIG_CMD_KGDB)
 151         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 152                 return;
 153 #endif
 154
 155         puts ("Machine check in kernel mode.\n"
 156                 "Caused by (from msr): ");
 157         printf("regs %p ",regs);
 158         switch( regs->msr & 0x000F0000) {
 159         case (0x80000000>>12):
 160                 puts ("Machine check signal - probably due to mm fault\n"
 161                         "with mmu off\n");
 162                 break;
 163         case (0x80000000>>13):
 164                 puts ("Transfer error ack signal\n");
 165                 break;
 166         case (0x80000000>>14):
 167                 puts ("Data parity signal\n");
 168                 break;
 169         case (0x80000000>>15):
 170                 puts ("Address parity signal\n");
 171                 break;
 172         default:
 173                 puts ("Unknown values in msr\n");
 174         }
 175         show_regs(regs);
 176         print_backtrace((unsigned long *)regs->gpr[1]);
 177 #ifdef CONFIG_PCI
 178         dump_pci();
 179 #endif
 180         panic("machine check");
 181 }
 182
 183 void
 184 AlignmentException(struct pt_regs *regs)
 185 {
 186 #if defined(CONFIG_CMD_KGDB)
 187         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 188                 return;
 189 #endif
 190         show_regs(regs);
 191         print_backtrace((unsigned long *)regs->gpr[1]);
 192         panic("Alignment Exception");
 193 }
 194
 195 void
 196 ProgramCheckException(struct pt_regs *regs)
 197 {
 198 #if defined(CONFIG_CMD_KGDB)
 199         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 200                 return;
 201 #endif
 202         show_regs(regs);
 203         print_backtrace((unsigned long *)regs->gpr[1]);
 204         panic("Program Check Exception");
 205 }
 206
 207 void
 208 SoftEmuException(struct pt_regs *regs)
 209 {
 210 #if defined(CONFIG_CMD_KGDB)
 211         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 212                 return;
 213 #endif
 214         show_regs(regs);
 215         print_backtrace((unsigned long *)regs->gpr[1]);
 216         panic("Software Emulation Exception");
 217 }
 218
 219
 220 void
 221 UnknownException(struct pt_regs *regs)
 222 {
 223 #if defined(CONFIG_CMD_KGDB)
 224         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 225                 return;
 226 #endif
 227         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 228                regs->nip, regs->msr, regs->trap);
 229         _exception(0, regs);
 230 }
 231
 232 #if defined(CONFIG_CMD_BEDBUG)
 233 extern void do_bedbug_breakpoint(struct pt_regs *);
 234 #endif
 235
 236 void
 237 DebugException(struct pt_regs *regs)
 238 {
 239
 240   printf("Debugger trap at @ %lx\n", regs->nip );
 241   show_regs(regs);
 242 #if defined(CONFIG_CMD_BEDBUG)
 243   do_bedbug_breakpoint( regs );
 244 #endif
 245 }
 246
 247 /* Probe an address by reading.  If not present, return -1, otherwise
 248  * return 0.
 249  */
 250 int
 251 addr_probe(uint *addr)
 252 {
 253 #if 0
 254         int     retval;
 255
 256         __asm__ __volatile__(                   \
 257                 "1:     lwz %0,0(%1)\n"         \
 258                 "       eieio\n"                \
 259                 "       li %0,0\n"              \
 260                 "2:\n"                          \
 261                 ".section .fixup,\"ax\"\n"      \
 262                 "3:     li %0,-1\n"             \
 263                 "       b 2b\n"                 \
 264                 ".section __ex_table,\"a\"\n"   \
 265                 "       .align 2\n"             \
 266                 "       .long 1b,3b\n"          \
 267                 ".text"                         \
 268                 : "=r" (retval) : "r"(addr));
 269
 270         return (retval);
 271 #endif
 272         return 0;
 273 }