/* * linux/arch/powerpc/kernel/traps.c * * Copyright 2007 Freescale Semiconductor. * Copyright (C) 2003 Motorola * Modified by Xianghua Xiao(x.xiao@motorola.com) * * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) * * Modified by Cort Dougan (cort@cs.nmt.edu) * and Paul Mackerras (paulus@cs.anu.edu.au) * * (C) Copyright 2000 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. * * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * */ /* * This file handles the architecture-dependent parts of hardware exceptions */ #include #include #include #include #include int machinecheck_count; int machinecheck_error; static inline void set_tsr(unsigned long val) { asm volatile("mtspr 0x150, %0" : : "r" (val)); } static inline unsigned long get_esr(void) { unsigned long val; asm volatile("mfspr %0, 0x03e" : "=r" (val) : ); return val; } #define ESR_MCI 0x80000000 #define ESR_PIL 0x08000000 #define ESR_PPR 0x04000000 #define ESR_PTR 0x02000000 #define ESR_DST 0x00800000 #define ESR_DIZ 0x00400000 #define ESR_U0F 0x00008000 /* * Trap & Exception support */ void print_backtrace(unsigned long *sp) { int cnt = 0; unsigned long i; printf("Call backtrace: "); while (sp) { if ((uint)sp > END_OF_MEM) break; i = sp[1]; if ((cnt++ % 7) == 0) printf("\n"); printf("%08lX ", i); if (cnt > 32) break; sp = (unsigned long *)*sp; } printf("\n"); } void show_regs(struct pt_regs *regs) { int i; printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx " "DAR: %08lX\n", regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar); printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x " "IR/DR: %01x%01x\n", regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0, regs->msr & MSR_FP ? 1 : 0, regs->msr&MSR_ME ? 1 : 0, regs->msr&MSR_IR ? 1 : 0, regs->msr&MSR_DR ? 1 : 0); printf("\n"); for (i = 0; i < 32; i++) { if ((i % 8) == 0) printf("GPR%02d: ", i); printf("%08lX ", regs->gpr[i]); if ((i % 8) == 7) printf("\n"); } } void _exception(int signr, struct pt_regs *regs) { show_regs(regs); print_backtrace((unsigned long *)regs->gpr[1]); panic("Exception in kernel pc %lx signal %d", regs->nip, signr); } void CritcalInputException(struct pt_regs *regs) { panic("Critical Input Exception"); } static int exception_init(void) { machinecheck_count = 0; machinecheck_error = 0; return 0; } core_initcall(exception_init); void MachineCheckException(struct pt_regs *regs) { unsigned long fixup; unsigned int mcsr, mcsrr0, mcsrr1, mcar; /* * Probing PCI using config cycles cause this exception * when a device is not present. Catch it and return to * the PCI exception handler. */ fixup = search_exception_table(regs->nip); if (fixup != 0) { regs->nip = fixup; return; } mcsrr0 = mfspr(SPRN_MCSRR0); mcsrr1 = mfspr(SPRN_MCSRR1); mcsr = mfspr(SPRN_MCSR); mcar = mfspr(SPRN_MCAR); machinecheck_count++; machinecheck_error = 1; #if defined(CONFIG_KGDB) if (debugger_exception_handler && (*debugger_exception_handler)(regs)) return; #endif printf("Machine check in kernel mode.\n"); printf("Caused by (from mcsr): "); printf("mcsr = 0x%08x\n", mcsr); if (mcsr & 0x80000000) printf("Machine check input pin\n"); if (mcsr & 0x40000000) printf("Instruction cache parity error\n"); if (mcsr & 0x20000000) printf("Data cache push parity error\n"); if (mcsr & 0x10000000) printf("Data cache parity error\n"); if (mcsr & 0x00000080) printf("Bus instruction address error\n"); if (mcsr & 0x00000040) printf("Bus Read address error\n"); if (mcsr & 0x00000020) printf("Bus Write address error\n"); if (mcsr & 0x00000010) printf("Bus Instruction data bus error\n"); if (mcsr & 0x00000008) printf("Bus Read data bus error\n"); if (mcsr & 0x00000004) printf("Bus Write bus error\n"); if (mcsr & 0x00000002) printf("Bus Instruction parity error\n"); if (mcsr & 0x00000001) printf("Bus Read parity error\n"); show_regs(regs); printf("MCSR=0x%08x\tMCSRR0=0x%08x\nMCSRR1=0x%08x\tMCAR=0x%08x\n", mcsr, mcsrr0, mcsrr1, mcar); print_backtrace((unsigned long *)regs->gpr[1]); if (machinecheck_count > 10) panic("machine check count too high\n"); if (machinecheck_count > 1) { regs->nip += 4; /* skip offending instruction */ printf("Skipping current instr, Returning to 0x%08lx\n", regs->nip); } else { printf("Returning back to 0x%08lx\n", regs->nip); } } void AlignmentException(struct pt_regs *regs) { #if defined(CONFIG_KGDB) if (debugger_exception_handler && (*debugger_exception_handler)(regs)) return; #endif show_regs(regs); print_backtrace((unsigned long *)regs->gpr[1]); panic("Alignment Exception"); } void ProgramCheckException(struct pt_regs *regs) { long esr_val; #if defined(CONFIG_KGDB) if (debugger_exception_handler && (*debugger_exception_handler)(regs)) return; #endif show_regs(regs); esr_val = get_esr(); if (esr_val & ESR_PIL) printf("** Illegal Instruction **\n"); else if (esr_val & ESR_PPR) printf("** Privileged Instruction **\n"); else if (esr_val & ESR_PTR) printf("** Trap Instruction **\n"); print_backtrace((unsigned long *)regs->gpr[1]); panic("Program Check Exception"); } void PITException(struct pt_regs *regs) { /* Reset PIT interrupt */ set_tsr(0x0c000000); } void UnknownException(struct pt_regs *regs) { #if defined(CONFIG_KGDB) if (debugger_exception_handler && (*debugger_exception_handler)(regs)) return; #endif printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", regs->nip, regs->msr, regs->trap); _exception(0, regs); } void DebugException(struct pt_regs *regs) { printf("Debugger trap at @ %lx\n", regs->nip); show_regs(regs); #if defined(CONFIG_BEDBUG) do_bedbug_breakpoint(regs); #endif }