arch/powerpc/cpu/mpc83xx/traps.c

   1 /*
   2  * (C) Copyright 2000
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 of
  10  * the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  20  * MA 02111-1307 USA
  21  */
  22
  23 /*
  24  * This file handles the architecture-dependent parts of hardware
  25  * exceptions
  26  */
  27
  28 #include <common.h>
  29 #include <command.h>
  30 #include <kgdb.h>
  31 #include <asm/processor.h>
  32 #include <asm/mpc8349_pci.h>
  33
  34 DECLARE_GLOBAL_DATA_PTR;
  35
  36 /* Returns 0 if exception not found and fixup otherwise.  */
  37 extern unsigned long search_exception_table(unsigned long);
  38
  39 #define END_OF_MEM      (gd->bd->bi_memstart + gd->bd->bi_memsize)
  40
  41 /*
  42  * Trap & Exception support
  43  */
  44
  45 void
  46 print_backtrace(unsigned long *sp)
  47 {
  48         int cnt = 0;
  49         unsigned long i;
  50
  51         puts ("Call backtrace: ");
  52         while (sp) {
  53                 if ((uint)sp > END_OF_MEM)
  54                         break;
  55
  56                 i = sp[1];
  57                 if (cnt++ % 7 == 0)
  58                         putc ('\n');
  59                 printf("%08lX ", i);
  60                 if (cnt > 32) break;
  61                 sp = (unsigned long *)*sp;
  62         }
  63         putc ('\n');
  64 }
  65
  66 void show_regs(struct pt_regs * regs)
  67 {
  68         int i;
  69
  70         printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
  71                regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  72         printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
  73                regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  74                regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  75                regs->msr&MSR_IR ? 1 : 0,
  76                regs->msr&MSR_DR ? 1 : 0);
  77
  78         putc ('\n');
  79         for (i = 0;  i < 32;  i++) {
  80                 if ((i % 8) == 0) {
  81                         printf("GPR%02d: ", i);
  82                 }
  83
  84                 printf("%08lX ", regs->gpr[i]);
  85                 if ((i % 8) == 7) {
  86                         putc ('\n');
  87                 }
  88         }
  89 }
  90
  91
  92 void
  93 _exception(int signr, struct pt_regs *regs)
  94 {
  95         show_regs(regs);
  96         print_backtrace((unsigned long *)regs->gpr[1]);
  97         panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
  98 }
  99
 100 #ifdef CONFIG_PCI
 101 void dump_pci (void)
 102 {
 103 /*
 104         volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 105         printf ("PCI: err status %x err mask %x err ctrl %x\n",
 106                 le32_to_cpu (immap->im_pci.pci_esr),
 107                 le32_to_cpu (immap->im_pci.pci_emr),
 108                 le32_to_cpu (immap->im_pci.pci_ecr));
 109         printf ("     error address %x error data %x ctrl %x\n",
 110                 le32_to_cpu (immap->im_pci.pci_eacr),
 111                 le32_to_cpu (immap->im_pci.pci_edcr),
 112                 le32_to_cpu (immap->im_pci.pci_eccr));
 113 */
 114 }
 115 #endif
 116
 117 void
 118 MachineCheckException(struct pt_regs *regs)
 119 {
 120         unsigned long fixup;
 121
 122         /* Probing PCI using config cycles cause this exception
 123          * when a device is not present.  Catch it and return to
 124          * the PCI exception handler.
 125          */
 126 #ifdef CONFIG_PCI
 127 #if 0
 128         volatile immap_t *immap  = (immap_t *)CONFIG_SYS_IMMR;
 129 #ifdef DEBUG
 130         dump_pci();
 131 #endif
 132         /* clear the error in the error status register */
 133         if(immap->im_pci.pci_esr & cpu_to_le32(PCI_ERROR_PCI_NO_RSP)) {
 134                 immap->im_pci.pci_esr = cpu_to_le32(PCI_ERROR_PCI_NO_RSP);
 135                 return;
 136         }
 137 #endif
 138 #endif /* CONFIG_PCI */
 139         if ((fixup = search_exception_table(regs->nip)) != 0) {
 140                 regs->nip = fixup;
 141                 return;
 142         }
 143
 144 #if defined(CONFIG_CMD_KGDB)
 145         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 146                 return;
 147 #endif
 148
 149         puts ("Machine check in kernel mode.\n"
 150                 "Caused by (from msr): ");
 151         printf("regs %p ",regs);
 152         switch( regs->msr & 0x000F0000) {
 153         case (0x80000000>>12):
 154                 puts ("Machine check signal - probably due to mm fault\n"
 155                         "with mmu off\n");
 156                 break;
 157         case (0x80000000>>13):
 158                 puts ("Transfer error ack signal\n");
 159                 break;
 160         case (0x80000000>>14):
 161                 puts ("Data parity signal\n");
 162                 break;
 163         case (0x80000000>>15):
 164                 puts ("Address parity signal\n");
 165                 break;
 166         default:
 167                 puts ("Unknown values in msr\n");
 168         }
 169         show_regs(regs);
 170         print_backtrace((unsigned long *)regs->gpr[1]);
 171 #ifdef CONFIG_PCI
 172         dump_pci();
 173 #endif
 174         panic("machine check");
 175 }
 176
 177 void
 178 AlignmentException(struct pt_regs *regs)
 179 {
 180 #if defined(CONFIG_CMD_KGDB)
 181         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 182                 return;
 183 #endif
 184         show_regs(regs);
 185         print_backtrace((unsigned long *)regs->gpr[1]);
 186         panic("Alignment Exception");
 187 }
 188
 189 void
 190 ProgramCheckException(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         show_regs(regs);
 197         print_backtrace((unsigned long *)regs->gpr[1]);
 198         panic("Program Check Exception");
 199 }
 200
 201 void
 202 SoftEmuException(struct pt_regs *regs)
 203 {
 204 #if defined(CONFIG_CMD_KGDB)
 205         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 206                 return;
 207 #endif
 208         show_regs(regs);
 209         print_backtrace((unsigned long *)regs->gpr[1]);
 210         panic("Software Emulation Exception");
 211 }
 212
 213
 214 void
 215 UnknownException(struct pt_regs *regs)
 216 {
 217 #if defined(CONFIG_CMD_KGDB)
 218         if (debugger_exception_handler && (*debugger_exception_handler)(regs))
 219                 return;
 220 #endif
 221         printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 222                regs->nip, regs->msr, regs->trap);
 223         _exception(0, regs);
 224 }
 225
 226 #if defined(CONFIG_CMD_BEDBUG)
 227 extern void do_bedbug_breakpoint(struct pt_regs *);
 228 #endif
 229
 230 void
 231 DebugException(struct pt_regs *regs)
 232 {
 233         printf("Debugger trap at @ %lx\n", regs->nip );
 234         show_regs(regs);
 235 #if defined(CONFIG_CMD_BEDBUG)
 236         do_bedbug_breakpoint( regs );
 237 #endif
 238 }
 239
 240 /* Probe an address by reading.  If not present, return -1, otherwise
 241  * return 0.
 242  */
 243 int
 244 addr_probe(uint *addr)
 245 {
 246 #if 0
 247         int     retval;
 248
 249         __asm__ __volatile__(                   \
 250                 "1:     lwz %0,0(%1)\n"         \
 251                 "       eieio\n"                \
 252                 "       li %0,0\n"              \
 253                 "2:\n"                          \
 254                 ".section .fixup,\"ax\"\n"      \
 255                 "3:     li %0,-1\n"             \
 256                 "       b 2b\n"                 \
 257                 ".section __ex_table,\"a\"\n"   \
 258                 "       .align 2\n"             \
 259                 "       .long 1b,3b\n"          \
 260                 ".text"                         \
 261                 : "=r" (retval) : "r"(addr));
 262
 263         return (retval);
 264 #endif
 265         return 0;
 266 }