1 /* 2 * linux/arch/powerpc/kernel/traps.c 3 * 4 * Copyright 2007 Freescale Semiconductor. 5 * Copyright (C) 2003 Motorola 6 * Modified by Xianghua Xiao(x.xiao@motorola.com) 7 * 8 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 9 * 10 * Modified by Cort Dougan (cort@cs.nmt.edu) 11 * and Paul Mackerras (paulus@cs.anu.edu.au) 12 * 13 * (C) Copyright 2000 14 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 15 * 16 * See file CREDITS for list of people who contributed to this 17 * project. 18 * 19 * This program is free software; you can redistribute it and/or 20 * modify it under the terms of the GNU General Public License as 21 * published by the Free Software Foundation; either version 2 of 22 * the License, or (at your option) any later version. 23 * 24 * This program is distributed in the hope that it will be useful, 25 * but WITHOUT ANY WARRANTY; without even the implied warranty of 26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 27 * GNU General Public License for more details. 28 * 29 * You should have received a copy of the GNU General Public License 30 * along with this program; if not, write to the Free Software 31 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 32 * MA 02111-1307 USA 33 */ 34 35 /* 36 * This file handles the architecture-dependent parts of hardware exceptions 37 */ 38 39 #include <common.h> 40 #include <command.h> 41 #include <kgdb.h> 42 #include <asm/processor.h> 43 44 DECLARE_GLOBAL_DATA_PTR; 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 addressable memory. This may be less than the actual 51 * amount of memory on the system if we're unable to keep all 52 * the memory mapped in. 53 */ 54 extern ulong get_effective_memsize(void); 55 #define END_OF_MEM (gd->bd->bi_memstart + get_effective_memsize()) 56 57 static __inline__ void set_tsr(unsigned long val) 58 { 59 asm volatile("mtspr 0x150, %0" : : "r" (val)); 60 } 61 62 static __inline__ unsigned long get_esr(void) 63 { 64 unsigned long val; 65 asm volatile("mfspr %0, 0x03e" : "=r" (val) :); 66 return val; 67 } 68 69 #define ESR_MCI 0x80000000 70 #define ESR_PIL 0x08000000 71 #define ESR_PPR 0x04000000 72 #define ESR_PTR 0x02000000 73 #define ESR_DST 0x00800000 74 #define ESR_DIZ 0x00400000 75 #define ESR_U0F 0x00008000 76 77 #if defined(CONFIG_CMD_BEDBUG) 78 extern void do_bedbug_breakpoint(struct pt_regs *); 79 #endif 80 81 /* 82 * Trap & Exception support 83 */ 84 85 void 86 print_backtrace(unsigned long *sp) 87 { 88 int cnt = 0; 89 unsigned long i; 90 91 printf("Call backtrace: "); 92 while (sp) { 93 if ((uint)sp > END_OF_MEM) 94 break; 95 96 i = sp[1]; 97 if (cnt++ % 7 == 0) 98 printf("\n"); 99 printf("%08lX ", i); 100 if (cnt > 32) break; 101 sp = (unsigned long *)*sp; 102 } 103 printf("\n"); 104 } 105 106 void show_regs(struct pt_regs * regs) 107 { 108 int i; 109 110 printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n", 111 regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar); 112 printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n", 113 regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0, 114 regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0, 115 regs->msr&MSR_IR ? 1 : 0, 116 regs->msr&MSR_DR ? 1 : 0); 117 118 printf("\n"); 119 for (i = 0; i < 32; i++) { 120 if ((i % 8) == 0) 121 { 122 printf("GPR%02d: ", i); 123 } 124 125 printf("%08lX ", regs->gpr[i]); 126 if ((i % 8) == 7) 127 { 128 printf("\n"); 129 } 130 } 131 } 132 133 134 void 135 _exception(int signr, struct pt_regs *regs) 136 { 137 show_regs(regs); 138 print_backtrace((unsigned long *)regs->gpr[1]); 139 panic("Exception in kernel pc %lx signal %d",regs->nip,signr); 140 } 141 142 void 143 CritcalInputException(struct pt_regs *regs) 144 { 145 panic("Critical Input Exception"); 146 } 147 148 int machinecheck_count = 0; 149 int machinecheck_error = 0; 150 void 151 MachineCheckException(struct pt_regs *regs) 152 { 153 unsigned long fixup; 154 unsigned int mcsr, mcsrr0, mcsrr1, mcar; 155 156 /* Probing PCI using config cycles cause this exception 157 * when a device is not present. Catch it and return to 158 * the PCI exception handler. 159 */ 160 if ((fixup = search_exception_table(regs->nip)) != 0) { 161 regs->nip = fixup; 162 return; 163 } 164 165 mcsrr0 = mfspr(SPRN_MCSRR0); 166 mcsrr1 = mfspr(SPRN_MCSRR1); 167 mcsr = mfspr(SPRN_MCSR); 168 mcar = mfspr(SPRN_MCAR); 169 170 machinecheck_count++; 171 machinecheck_error=1; 172 173 #if defined(CONFIG_CMD_KGDB) 174 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 175 return; 176 #endif 177 178 printf("Machine check in kernel mode.\n"); 179 printf("Caused by (from mcsr): "); 180 printf("mcsr = 0x%08x\n", mcsr); 181 if (mcsr & 0x80000000) 182 printf("Machine check input pin\n"); 183 if (mcsr & 0x40000000) 184 printf("Instruction cache parity error\n"); 185 if (mcsr & 0x20000000) 186 printf("Data cache push parity error\n"); 187 if (mcsr & 0x10000000) 188 printf("Data cache parity error\n"); 189 if (mcsr & 0x00000080) 190 printf("Bus instruction address error\n"); 191 if (mcsr & 0x00000040) 192 printf("Bus Read address error\n"); 193 if (mcsr & 0x00000020) 194 printf("Bus Write address error\n"); 195 if (mcsr & 0x00000010) 196 printf("Bus Instruction data bus error\n"); 197 if (mcsr & 0x00000008) 198 printf("Bus Read data bus error\n"); 199 if (mcsr & 0x00000004) 200 printf("Bus Write bus error\n"); 201 if (mcsr & 0x00000002) 202 printf("Bus Instruction parity error\n"); 203 if (mcsr & 0x00000001) 204 printf("Bus Read parity error\n"); 205 206 show_regs(regs); 207 printf("MCSR=0x%08x \tMCSRR0=0x%08x \nMCSRR1=0x%08x \tMCAR=0x%08x\n", 208 mcsr, mcsrr0, mcsrr1, mcar); 209 print_backtrace((unsigned long *)regs->gpr[1]); 210 if (machinecheck_count > 10) { 211 panic("machine check count too high\n"); 212 } 213 214 if (machinecheck_count > 1) { 215 regs->nip += 4; /* skip offending instruction */ 216 printf("Skipping current instr, Returning to 0x%08lx\n", 217 regs->nip); 218 } else { 219 printf("Returning back to 0x%08lx\n",regs->nip); 220 } 221 } 222 223 void 224 AlignmentException(struct pt_regs *regs) 225 { 226 #if defined(CONFIG_CMD_KGDB) 227 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 228 return; 229 #endif 230 231 show_regs(regs); 232 print_backtrace((unsigned long *)regs->gpr[1]); 233 panic("Alignment Exception"); 234 } 235 236 void 237 ProgramCheckException(struct pt_regs *regs) 238 { 239 long esr_val; 240 241 #if defined(CONFIG_CMD_KGDB) 242 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 243 return; 244 #endif 245 246 show_regs(regs); 247 248 esr_val = get_esr(); 249 if( esr_val & ESR_PIL ) 250 printf( "** Illegal Instruction **\n" ); 251 else if( esr_val & ESR_PPR ) 252 printf( "** Privileged Instruction **\n" ); 253 else if( esr_val & ESR_PTR ) 254 printf( "** Trap Instruction **\n" ); 255 256 print_backtrace((unsigned long *)regs->gpr[1]); 257 panic("Program Check Exception"); 258 } 259 260 void 261 PITException(struct pt_regs *regs) 262 { 263 /* 264 * Reset PIT interrupt 265 */ 266 set_tsr(0x0c000000); 267 268 /* 269 * Call timer_interrupt routine in interrupts.c 270 */ 271 timer_interrupt(NULL); 272 } 273 274 275 void 276 UnknownException(struct pt_regs *regs) 277 { 278 #if defined(CONFIG_CMD_KGDB) 279 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 280 return; 281 #endif 282 283 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", 284 regs->nip, regs->msr, regs->trap); 285 _exception(0, regs); 286 } 287 288 void 289 ExtIntException(struct pt_regs *regs) 290 { 291 volatile ccsr_pic_t *pic = (void *)(CONFIG_SYS_MPC8xxx_PIC_ADDR); 292 293 uint vect; 294 295 #if defined(CONFIG_CMD_KGDB) 296 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 297 return; 298 #endif 299 300 printf("External Interrupt Exception at PC: %lx, SR: %lx, vector=%lx", 301 regs->nip, regs->msr, regs->trap); 302 vect = pic->iack0; 303 printf(" irq IACK0@%05x=%d\n",(int)&pic->iack0,vect); 304 show_regs(regs); 305 print_backtrace((unsigned long *)regs->gpr[1]); 306 } 307 308 void 309 DebugException(struct pt_regs *regs) 310 { 311 printf("Debugger trap at @ %lx\n", regs->nip ); 312 show_regs(regs); 313 #if defined(CONFIG_CMD_BEDBUG) 314 do_bedbug_breakpoint( regs ); 315 #endif 316 } 317 318 /* Probe an address by reading. If not present, return -1, otherwise 319 * return 0. 320 */ 321 int 322 addr_probe(uint *addr) 323 { 324 return 0; 325 } 326