1 /* 2 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 3 * 4 * Modified by Cort Dougan (cort@cs.nmt.edu) 5 * and Paul Mackerras (paulus@cs.anu.edu.au) 6 * 7 * (C) Copyright 2000 8 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 9 * 10 * See file CREDITS for list of people who contributed to this 11 * project. 12 * 13 * This program is free software; you can redistribute it and/or 14 * modify it under the terms of the GNU General Public License as 15 * published by the Free Software Foundation; either version 2 of 16 * the License, or (at your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with this program; if not, write to the Free Software 25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 26 * MA 02111-1307 USA 27 */ 28 29 /* 30 * This file handles the architecture-dependent parts of hardware exceptions 31 */ 32 33 #include <common.h> 34 #include <command.h> 35 #include <kgdb.h> 36 #include <asm/processor.h> 37 38 DECLARE_GLOBAL_DATA_PTR; 39 40 /* Returns 0 if exception not found and fixup otherwise. */ 41 extern unsigned long search_exception_table(unsigned long); 42 43 /* 44 * End of addressable memory. This may be less than the actual 45 * amount of memory on the system if we're unable to keep all 46 * the memory mapped in. 47 */ 48 extern ulong get_effective_memsize(void); 49 #define END_OF_MEM (gd->bd->bi_memstart + get_effective_memsize()) 50 51 /* 52 * Trap & Exception support 53 */ 54 55 static void print_backtrace(unsigned long *sp) 56 { 57 int cnt = 0; 58 unsigned long i; 59 60 printf("Call backtrace: "); 61 while (sp) { 62 if ((uint) sp > END_OF_MEM) 63 break; 64 65 i = sp[1]; 66 if (cnt++ % 7 == 0) 67 printf("\n"); 68 printf("%08lX ", i); 69 if (cnt > 32) 70 break; 71 sp = (unsigned long *)*sp; 72 } 73 printf("\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:" 81 " %p TRAP: %04lx DAR: %08lX\n", 82 regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar); 83 printf("MSR: %08lx EE: %01x PR: %01x FP:" 84 " %01x ME: %01x IR/DR: %01x%01x\n", 85 regs->msr, regs->msr & MSR_EE ? 1 : 0, 86 regs->msr & MSR_PR ? 1 : 0, regs->msr & MSR_FP ? 1 : 0, 87 regs->msr & MSR_ME ? 1 : 0, regs->msr & MSR_IR ? 1 : 0, 88 regs->msr & MSR_DR ? 1 : 0); 89 90 printf("\n"); 91 for (i = 0; i < 32; i++) { 92 if ((i % 8) == 0) { 93 printf("GPR%02d: ", i); 94 } 95 96 printf("%08lX ", regs->gpr[i]); 97 if ((i % 8) == 7) { 98 printf("\n"); 99 } 100 } 101 } 102 103 104 static void _exception(int signr, struct pt_regs *regs) 105 { 106 show_regs(regs); 107 print_backtrace((unsigned long *)regs->gpr[1]); 108 panic("Exception in kernel pc %lx signal %d", regs->nip, signr); 109 } 110 111 void MachineCheckException(struct pt_regs *regs) 112 { 113 unsigned long fixup; 114 115 /* Probing PCI using config cycles cause this exception 116 * when a device is not present. Catch it and return to 117 * the PCI exception handler. 118 */ 119 if ((fixup = search_exception_table(regs->nip)) != 0) { 120 regs->nip = fixup; 121 return; 122 } 123 124 #if defined(CONFIG_CMD_KGDB) 125 if (debugger_exception_handler && (*debugger_exception_handler) (regs)) 126 return; 127 #endif 128 129 printf("Machine check in kernel mode.\n"); 130 printf("Caused by (from msr): "); 131 printf("regs %p ", regs); 132 switch ( regs->msr & 0x001F0000) { 133 case (0x80000000>>11): 134 printf("MSS error. MSSSR0: %08x\n", mfspr(SPRN_MSSSR0)); 135 break; 136 case (0x80000000>>12): 137 printf("Machine check signal - probably due to mm fault\n" 138 "with mmu off\n"); 139 break; 140 case (0x80000000 >> 13): 141 printf("Transfer error ack signal\n"); 142 break; 143 case (0x80000000 >> 14): 144 printf("Data parity signal\n"); 145 break; 146 case (0x80000000 >> 15): 147 printf("Address parity signal\n"); 148 break; 149 default: 150 printf("Unknown values in msr\n"); 151 } 152 show_regs(regs); 153 print_backtrace((unsigned long *)regs->gpr[1]); 154 panic("machine check"); 155 } 156 157 void AlignmentException(struct pt_regs *regs) 158 { 159 #if defined(CONFIG_CMD_KGDB) 160 if (debugger_exception_handler && (*debugger_exception_handler) (regs)) 161 return; 162 #endif 163 show_regs(regs); 164 print_backtrace((unsigned long *)regs->gpr[1]); 165 panic("Alignment Exception"); 166 } 167 168 void ProgramCheckException(struct pt_regs *regs) 169 { 170 unsigned char *p = regs ? (unsigned char *)(regs->nip) : NULL; 171 int i, j; 172 173 #if defined(CONFIG_CMD_KGDB) 174 if (debugger_exception_handler && (*debugger_exception_handler) (regs)) 175 return; 176 #endif 177 show_regs(regs); 178 179 p = (unsigned char *)((unsigned long)p & 0xFFFFFFE0); 180 p -= 32; 181 for (i = 0; i < 256; i += 16) { 182 printf("%08x: ", (unsigned int)p + i); 183 for (j = 0; j < 16; j++) { 184 printf("%02x ", p[i + j]); 185 } 186 printf("\n"); 187 } 188 189 print_backtrace((unsigned long *)regs->gpr[1]); 190 panic("Program Check Exception"); 191 } 192 193 void SoftEmuException(struct pt_regs *regs) 194 { 195 #if defined(CONFIG_CMD_KGDB) 196 if (debugger_exception_handler && (*debugger_exception_handler) (regs)) 197 return; 198 #endif 199 show_regs(regs); 200 print_backtrace((unsigned long *)regs->gpr[1]); 201 panic("Software Emulation Exception"); 202 } 203 204 void UnknownException(struct pt_regs *regs) 205 { 206 #if defined(CONFIG_CMD_KGDB) 207 if (debugger_exception_handler && (*debugger_exception_handler) (regs)) 208 return; 209 #endif 210 printf("UnknownException regs@%lx\n", (ulong)regs); 211 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", 212 regs->nip, regs->msr, regs->trap); 213 _exception(0, regs); 214 } 215 216 /* 217 * Probe an address by reading. 218 * If not present, return -1, 219 * otherwise return 0. 220 */ 221 int addr_probe(uint *addr) 222 { 223 return 0; 224 } 225