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 static void print_backtrace(unsigned long *sp) 86 { 87 int cnt = 0; 88 unsigned long i; 89 90 printf("Call backtrace: "); 91 while (sp) { 92 if ((uint)sp > END_OF_MEM) 93 break; 94 95 i = sp[1]; 96 if (cnt++ % 7 == 0) 97 printf("\n"); 98 printf("%08lX ", i); 99 if (cnt > 32) break; 100 sp = (unsigned long *)*sp; 101 } 102 printf("\n"); 103 } 104 105 void show_regs(struct pt_regs *regs) 106 { 107 int i; 108 109 printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n", 110 regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar); 111 printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n", 112 regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0, 113 regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0, 114 regs->msr&MSR_IR ? 1 : 0, 115 regs->msr&MSR_DR ? 1 : 0); 116 117 printf("\n"); 118 for (i = 0; i < 32; i++) { 119 if ((i % 8) == 0) 120 { 121 printf("GPR%02d: ", i); 122 } 123 124 printf("%08lX ", regs->gpr[i]); 125 if ((i % 8) == 7) 126 { 127 printf("\n"); 128 } 129 } 130 } 131 132 133 static void _exception(int signr, struct pt_regs *regs) 134 { 135 show_regs(regs); 136 print_backtrace((unsigned long *)regs->gpr[1]); 137 panic("Exception in kernel pc %lx signal %d",regs->nip,signr); 138 } 139 140 void CritcalInputException(struct pt_regs *regs) 141 { 142 panic("Critical Input Exception"); 143 } 144 145 int machinecheck_count = 0; 146 int machinecheck_error = 0; 147 void MachineCheckException(struct pt_regs *regs) 148 { 149 unsigned long fixup; 150 unsigned int mcsr, mcsrr0, mcsrr1, mcar; 151 152 /* Probing PCI using config cycles cause this exception 153 * when a device is not present. Catch it and return to 154 * the PCI exception handler. 155 */ 156 if ((fixup = search_exception_table(regs->nip)) != 0) { 157 regs->nip = fixup; 158 return; 159 } 160 161 mcsrr0 = mfspr(SPRN_MCSRR0); 162 mcsrr1 = mfspr(SPRN_MCSRR1); 163 mcsr = mfspr(SPRN_MCSR); 164 mcar = mfspr(SPRN_MCAR); 165 166 machinecheck_count++; 167 machinecheck_error=1; 168 169 #if defined(CONFIG_CMD_KGDB) 170 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 171 return; 172 #endif 173 174 printf("Machine check in kernel mode.\n"); 175 printf("Caused by (from mcsr): "); 176 printf("mcsr = 0x%08x\n", mcsr); 177 if (mcsr & 0x80000000) 178 printf("Machine check input pin\n"); 179 if (mcsr & 0x40000000) 180 printf("Instruction cache parity error\n"); 181 if (mcsr & 0x20000000) 182 printf("Data cache push parity error\n"); 183 if (mcsr & 0x10000000) 184 printf("Data cache parity error\n"); 185 if (mcsr & 0x00000080) 186 printf("Bus instruction address error\n"); 187 if (mcsr & 0x00000040) 188 printf("Bus Read address error\n"); 189 if (mcsr & 0x00000020) 190 printf("Bus Write address error\n"); 191 if (mcsr & 0x00000010) 192 printf("Bus Instruction data bus error\n"); 193 if (mcsr & 0x00000008) 194 printf("Bus Read data bus error\n"); 195 if (mcsr & 0x00000004) 196 printf("Bus Write bus error\n"); 197 if (mcsr & 0x00000002) 198 printf("Bus Instruction parity error\n"); 199 if (mcsr & 0x00000001) 200 printf("Bus Read parity error\n"); 201 202 show_regs(regs); 203 printf("MCSR=0x%08x \tMCSRR0=0x%08x \nMCSRR1=0x%08x \tMCAR=0x%08x\n", 204 mcsr, mcsrr0, mcsrr1, mcar); 205 print_backtrace((unsigned long *)regs->gpr[1]); 206 if (machinecheck_count > 10) { 207 panic("machine check count too high\n"); 208 } 209 210 if (machinecheck_count > 1) { 211 regs->nip += 4; /* skip offending instruction */ 212 printf("Skipping current instr, Returning to 0x%08lx\n", 213 regs->nip); 214 } else { 215 printf("Returning back to 0x%08lx\n",regs->nip); 216 } 217 } 218 219 void AlignmentException(struct pt_regs *regs) 220 { 221 #if defined(CONFIG_CMD_KGDB) 222 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 223 return; 224 #endif 225 226 show_regs(regs); 227 print_backtrace((unsigned long *)regs->gpr[1]); 228 panic("Alignment Exception"); 229 } 230 231 void ProgramCheckException(struct pt_regs *regs) 232 { 233 long esr_val; 234 235 #if defined(CONFIG_CMD_KGDB) 236 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 237 return; 238 #endif 239 240 show_regs(regs); 241 242 esr_val = get_esr(); 243 if( esr_val & ESR_PIL ) 244 printf( "** Illegal Instruction **\n" ); 245 else if( esr_val & ESR_PPR ) 246 printf( "** Privileged Instruction **\n" ); 247 else if( esr_val & ESR_PTR ) 248 printf( "** Trap Instruction **\n" ); 249 250 print_backtrace((unsigned long *)regs->gpr[1]); 251 panic("Program Check Exception"); 252 } 253 254 void PITException(struct pt_regs *regs) 255 { 256 /* 257 * Reset PIT interrupt 258 */ 259 set_tsr(0x0c000000); 260 261 /* 262 * Call timer_interrupt routine in interrupts.c 263 */ 264 timer_interrupt(NULL); 265 } 266 267 void UnknownException(struct pt_regs *regs) 268 { 269 #if defined(CONFIG_CMD_KGDB) 270 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 271 return; 272 #endif 273 274 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", 275 regs->nip, regs->msr, regs->trap); 276 _exception(0, regs); 277 } 278 279 void ExtIntException(struct pt_regs *regs) 280 { 281 volatile ccsr_pic_t *pic = (void *)(CONFIG_SYS_MPC8xxx_PIC_ADDR); 282 283 uint vect; 284 285 #if defined(CONFIG_CMD_KGDB) 286 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 287 return; 288 #endif 289 290 printf("External Interrupt Exception at PC: %lx, SR: %lx, vector=%lx", 291 regs->nip, regs->msr, regs->trap); 292 vect = pic->iack0; 293 printf(" irq IACK0@%05x=%d\n",(int)&pic->iack0,vect); 294 show_regs(regs); 295 print_backtrace((unsigned long *)regs->gpr[1]); 296 } 297 298 void DebugException(struct pt_regs *regs) 299 { 300 printf("Debugger trap at @ %lx\n", regs->nip ); 301 show_regs(regs); 302 #if defined(CONFIG_CMD_BEDBUG) 303 do_bedbug_breakpoint( regs ); 304 #endif 305 } 306 307 /* Probe an address by reading. If not present, return -1, otherwise 308 * return 0. 309 */ 310 int addr_probe(uint *addr) 311 { 312 return 0; 313 } 314