/* * 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) * * (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. * * 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	0x00400000static __inline__ void set_tsr(unsigned long val){#if defined(CONFIG_440)	asm volatile("mtspr 0x150, %0" : : "r" (val));#else	asm volatile("mttsr %0" : : "r" (val));#endif}static __inline__ unsigned long get_esr(void){	unsigned long val;#if defined(CONFIG_440)	asm volatile("mfspr %0, 0x03e" : "=r" (val) :);#else	asm volatile("mfesr %0" : "=r" (val) :);#endif	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#if (CONFIG_COMMANDS & CFG_CMD_BEDBUG)extern void do_bedbug_breakpoint(struct pt_regs *);#endif/* * Trap & Exception support */voidprint_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);}voidMachineCheckException(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);	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");}voidAlignmentException(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");}voidProgramCheckException(struct pt_regs *regs){	long esr_val;#if (CONFIG_COMMANDS & CFG_CMD_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");}voidPITException(struct pt_regs *regs){	/*	 * Reset PIT interrupt	 */	set_tsr(0x08000000);	/*	 * Call timer_interrupt routine in interrupts.c	 */	timer_interrupt(NULL);}voidUnknownException(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);}voidDebugException(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. */intaddr_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;}