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 <asm/processor.h>
  38 #include <asm/m8260_pci.h>
  39
  40 #if defined(CONFIG_CMD_KGDB)
  41 int (*debugger_exception_handler)(struct pt_regs *) = 0;
  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 #define END_OF_MEM      0x02000000
  50
  51 /*
  52  * Trap & Exception support
  53  */
  54
  55 void
  56 print_backtrace(unsigned long *sp)
  57 {
  58         int cnt = 0;
  59         unsigned long i;
  60
  61         puts ("Call backtrace: ");
  62         while (sp) {
  63                 if ((uint)sp > END_OF_MEM)
  64                         break;
  65
  66                 i = sp[1];
  67                 if (cnt++ % 7 == 0)
  68                         putc ('\n');
  69                 printf("%08lX ", i);
  70                 if (cnt > 32) break;
  71                 sp = (unsigned long *)*sp;
  72         }
  73         putc ('\n');
  74 }
  75
  76 void show_regs(struct pt_regs * regs)
  77 {
  78         int i;
  79
  80         printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
  81                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  82         printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
  83                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  84                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  85                regs->msr&MSR_IR ? 1 : 0,
  86                regs->msr&MSR_DR ? 1 : 0);
  87
  88         putc ('\n');
  89         for (i = 0;  i < 32;  i++) {
  90                 if ((i % 8) == 0) {
  91                         printf("GPR%02d: ", i);
  92                 }
  93
  94                 printf("%08lX ", regs->gpr[i]);
  95                 if ((i % 8) == 7) {
  96                         putc ('\n');
  97                 }
  98         }
  99 }
 100
 101
 102 void
 103 _exception(int signr, struct pt_regs *regs)
 104 {
 105         show_regs(regs);
 106         print_backtrace((unsigned long *)regs->gpr[1]);
 107         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
 108 }
 109
 110 #ifdef CONFIG_PCI
 111 void dump_pci (void)
 112 {
 113
 114         volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 115
 116         printf ("PCI: err status %x err mask %x err ctrl %x\n",
 117                 le32_to_cpu (immap->im_pci.pci_esr),
 118                 le32_to_cpu (immap->im_pci.pci_emr),
 119                 le32_to_cpu (immap->im_pci.pci_ecr));
 120         printf ("     error address %x error data %x ctrl %x\n",
 121                 le32_to_cpu (immap->im_pci.pci_eacr),
 122                 le32_to_cpu (immap->im_pci.pci_edcr),
 123                 le32_to_cpu (immap->im_pci.pci_eccr));
 124
 125 }
 126 #endif
 127
 128 void
 129 MachineCheckException(struct pt_regs *regs)
 130 {
 131         unsigned long fixup;
 132
 133         /* Probing PCI using config cycles cause this exception
 134          * when a device is not present.  Catch it and return to
 135          * the PCI exception handler.
 136          */
 137 #ifdef CONFIG_PCI
 138         volatile immap_t *immap  = (immap_t *)CONFIG_SYS_IMMR;
 139 #ifdef DEBUG
 140         dump_pci();
 141 #endif
 142         /* clear the error in the error status register */
 143         if(immap->im_pci.pci_esr & cpu_to_le32(PCI_ERROR_PCI_NO_RSP)) {
 144                 immap->im_pci.pci_esr = cpu_to_le32(PCI_ERROR_PCI_NO_RSP);
 145                 return;
 146         }
 147 #endif
 148         if ((fixup = search_exception_table(regs->nip)) != 0) {
 149                 regs->nip = fixup;
 150                 return;
 151         }
 152
 153 #if defined(CONFIG_CMD_KGDB)
 154         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 155                 return;
 156 #endif
 157
 158         puts ("Machine check in kernel mode.\n"
 159                 "Caused by (from msr): ");
 160         printf("regs %p ",regs);
 161         switch( regs->msr & 0x000F0000) {
 162         case (0x80000000>>12):
 163                 puts ("Machine check signal - probably due to mm fault\n"
 164                         "with mmu off\n");
 165                 break;
 166         case (0x80000000>>13):
 167                 puts ("Transfer error ack signal\n");
 168                 break;
 169         case (0x80000000>>14):
 170                 puts ("Data parity signal\n");
 171                 break;
 172         case (0x80000000>>15):
 173                 puts ("Address parity signal\n");
 174                 break;
 175         default:
 176                 puts ("Unknown values in msr\n");
 177         }
 178         show_regs(regs);
 179         print_backtrace((unsigned long *)regs->gpr[1]);
 180 #ifdef CONFIG_PCI
 181         dump_pci();
 182 #endif
 183         panic("machine check");
 184 }
 185
 186 void
 187 AlignmentException(struct pt_regs *regs)
 188 {
 189 #if defined(CONFIG_CMD_KGDB)
 190         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 191                 return;
 192 #endif
 193         show_regs(regs);
 194         print_backtrace((unsigned long *)regs->gpr[1]);
 195         panic("Alignment Exception");
 196 }
 197
 198 void
 199 ProgramCheckException(struct pt_regs *regs)
 200 {
 201 #if defined(CONFIG_CMD_KGDB)
 202         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 203                 return;
 204 #endif
 205         show_regs(regs);
 206         print_backtrace((unsigned long *)regs->gpr[1]);
 207         panic("Program Check Exception");
 208 }
 209
 210 void
 211 SoftEmuException(struct pt_regs *regs)
 212 {
 213 #if defined(CONFIG_CMD_KGDB)
 214         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 215                 return;
 216 #endif
 217         show_regs(regs);
 218         print_backtrace((unsigned long *)regs->gpr[1]);
 219         panic("Software Emulation Exception");
 220 }
 221
 222
 223 void
 224 UnknownException(struct pt_regs *regs)
 225 {
 226 #if defined(CONFIG_CMD_KGDB)
 227         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 228                 return;
 229 #endif
 230         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 231                regs->nip, regs->msr, regs->trap);
 232         _exception(0, regs);
 233 }
 234
 235 #if defined(CONFIG_CMD_BEDBUG)
 236 extern void do_bedbug_breakpoint(struct pt_regs *);
 237 #endif
 238
 239 void
 240 DebugException(struct pt_regs *regs)
 241 {
 242
 243   printf("Debugger trap at @ %lx\n", regs->nip );
 244   show_regs(regs);
 245 #if defined(CONFIG_CMD_BEDBUG)
 246   do_bedbug_breakpoint( regs );
 247 #endif
 248 }
 249
 250 /* Probe an address by reading.  If not present, return -1, otherwise
 251  * return 0.
 252  */
 253 int
 254 addr_probe(uint *addr)
 255 {
 256 #if 0
 257         int     retval;
 258
 259         __asm__ __volatile__(                   \
 260                 "1:     lwz %0,0(%1)\n"         \
 261                 "       eieio\n"                \
 262                 "       li %0,0\n"              \
 263                 "2:\n"                          \
 264                 ".section .fixup,\"ax\"\n"      \
 265                 "3:     li %0,-1\n"             \
 266                 "       b 2b\n"                 \
 267                 ".section __ex_table,\"a\"\n"   \
 268                 "       .align 2\n"             \
 269                 "       .long 1b,3b\n"          \
 270                 ".text"                         \
 271                 : "=r" (retval) : "r"(addr));
 272
 273         return (retval);
 274 #endif
 275         return 0;
 276 }