/* * linux/arch/ppc/kernel/traps.c * * 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) * fixed Machine Check Reasons by Reinhard Meyer (r.meyer@emk-elektronik.de) * * (C) Copyright 2000-2003 * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA *//* * This file handles the architecture-dependent parts of hardware exceptions */#include <common.h>#include <command.h>#include <asm/processor.h>#if (CONFIG_COMMANDS & CFG_CMD_KGDB)int (*debugger_exception_handler) (struct pt_regs *) = 0;#endif/* Returns 0 if exception not found and fixup otherwise.  */extern unsigned long search_exception_table (unsigned long);/* THIS NEEDS CHANGING to use the board info structure.*/#define END_OF_MEM      0x02000000/* * 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 MachineCheckException (struct pt_regs *regs){	unsigned long fixup;	/* Probing PCI using config cycles cause this exception	 * when a device is not present.  Catch it and return to	 * the PCI exception handler.	 */	if ((fixup = search_exception_table (regs->nip)) != 0) {		regs->nip = fixup;		return;	}#if (CONFIG_COMMANDS & CFG_CMD_KGDB)	if (debugger_exception_handler	    && (*debugger_exception_handler) (regs))		return;#endif	printf ("Machine check in kernel mode.\n");	printf ("Caused by (from msr): ");	printf ("regs %p ", regs);	/* refer to 603e Manual (MPC603EUM/AD), chapter 4.5.2.1 */	switch (regs->msr & 0x000F0000) {	case (0x80000000 >> 12):		printf ("Machine check signal - probably due to mm fault\n"			"with mmu off\n");		break;	case (0x80000000 >> 13):		printf ("Transfer error ack signal\n");		break;	case (0x80000000 >> 14):		printf ("Data parity signal\n");		break;	case (0x80000000 >> 15):		printf ("Address parity signal\n");		break;	default:		printf ("Unknown values in msr\n");	}	show_regs (regs);	print_backtrace ((unsigned long *) regs->gpr[1]);	panic ("machine check");}void AlignmentException (struct pt_regs *regs){#if (CONFIG_COMMANDS & CFG_CMD_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){#if (CONFIG_COMMANDS & CFG_CMD_KGDB)	if (debugger_exception_handler	    && (*debugger_exception_handler) (regs))		return;#endif	show_regs (regs);	print_backtrace ((unsigned long *) regs->gpr[1]);	panic ("Program Check Exception");}void SoftEmuException (struct pt_regs *regs){#if (CONFIG_COMMANDS & CFG_CMD_KGDB)	if (debugger_exception_handler	    && (*debugger_exception_handler) (regs))		return;#endif	show_regs (regs);	print_backtrace ((unsigned long *) regs->gpr[1]);	panic ("Software Emulation Exception");}void UnknownException (struct pt_regs *regs){#if (CONFIG_COMMANDS & CFG_CMD_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);}#if (CONFIG_COMMANDS & CFG_CMD_BEDBUG)extern void do_bedbug_breakpoint (struct pt_regs *);#endifvoid DebugException (struct pt_regs *regs){	printf ("Debugger trap at @ %lx\n", regs->nip);	show_regs (regs);#if (CONFIG_COMMANDS & CFG_CMD_BEDBUG)	do_bedbug_breakpoint (regs);#endif}/* Probe an address by reading.  If not present, return -1, otherwise * return 0. */int addr_probe (uint * addr){#if 0	int retval;	__asm__ __volatile__ ("1: lwz %0,0(%1)\n"			      "   eieio\n"			      "   li %0,0\n"			      "2:\n"			      ".section .fixup,\"ax\"\n"			      "3: li %0,-1\n"			      "   b 2b\n"			      ".section __ex_table,\"a\"\n"			      "   .align 2\n"			      "   .long 1b,3b\n"			      ".text":"=r" (retval):"r" (addr));	return (retval);#endif	return 0;}