[net-next-2.6.git] / arch / microblaze / kernel / exceptions.c

/*
 * HW exception handling
 *
 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
 * Copyright (C) 2008 PetaLogix
 *
 * This file is subject to the terms and conditions of the GNU General
 * Public License.  See the file COPYING in the main directory of this
 * archive for more details.
 */

/*
 * This file handles the architecture-dependent parts of hardware exceptions
 */

#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kallsyms.h>
#include <linux/module.h>

#include <asm/exceptions.h>
#include <asm/entry.h>		/* For KM CPU var */
#include <linux/uaccess.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <asm/current.h>

#define MICROBLAZE_ILL_OPCODE_EXCEPTION	0x02
#define MICROBLAZE_IBUS_EXCEPTION	0x03
#define MICROBLAZE_DBUS_EXCEPTION	0x04
#define MICROBLAZE_DIV_ZERO_EXCEPTION	0x05
#define MICROBLAZE_FPU_EXCEPTION	0x06
#define MICROBLAZE_PRIVILEGED_EXCEPTION	0x07

static DEFINE_SPINLOCK(die_lock);

void die(const char *str, struct pt_regs *fp, long err)
{
	console_verbose();
	spin_lock_irq(&die_lock);
	printk(KERN_WARNING "Oops: %s, sig: %ld\n", str, err);
	show_regs(fp);
	spin_unlock_irq(&die_lock);
	/* do_exit() should take care of panic'ing from an interrupt
	 * context so we don't handle it here
	 */
	do_exit(err);
}

/* for user application debugging */
void sw_exception(struct pt_regs *regs)
{
	_exception(SIGTRAP, regs, TRAP_BRKPT, regs->r16);
}

void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
{
	siginfo_t info;

	if (kernel_mode(regs)) {
		die("Exception in kernel mode", regs, signr);
	}
	info.si_signo = signr;
	info.si_errno = 0;
	info.si_code = code;
	info.si_addr = (void __user *) addr;
	force_sig_info(signr, &info, current);
}

asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
							int fsr, int addr)
{
#ifdef CONFIG_MMU
	int code;
	addr = regs->pc;
#endif

#if 0
	printk(KERN_WARNING "Exception %02x in %s mode, FSR=%08x PC=%08x " \
							"ESR=%08x\n",
			type, user_mode(regs) ? "user" : "kernel", fsr,
			(unsigned int) regs->pc, (unsigned int) regs->esr);
#endif

	switch (type & 0x1F) {
	case MICROBLAZE_ILL_OPCODE_EXCEPTION:
		if (user_mode(regs)) {
			pr_debug(KERN_WARNING "Illegal opcode exception " \
							"in user mode.\n");
			_exception(SIGILL, regs, ILL_ILLOPC, addr);
			return;
		}
		printk(KERN_WARNING "Illegal opcode exception " \
							"in kernel mode.\n");
		die("opcode exception", regs, SIGBUS);
		break;
	case MICROBLAZE_IBUS_EXCEPTION:
		if (user_mode(regs)) {
			pr_debug(KERN_WARNING "Instruction bus error " \
						"exception in user mode.\n");
			_exception(SIGBUS, regs, BUS_ADRERR, addr);
			return;
		}
		printk(KERN_WARNING "Instruction bus error exception " \
							"in kernel mode.\n");
		die("bus exception", regs, SIGBUS);
		break;
	case MICROBLAZE_DBUS_EXCEPTION:
		if (user_mode(regs)) {
			pr_debug(KERN_WARNING "Data bus error exception " \
							"in user mode.\n");
			_exception(SIGBUS, regs, BUS_ADRERR, addr);
			return;
		}
		printk(KERN_WARNING "Data bus error exception " \
							"in kernel mode.\n");
		die("bus exception", regs, SIGBUS);
		break;
	case MICROBLAZE_DIV_ZERO_EXCEPTION:
		if (user_mode(regs)) {
			pr_debug(KERN_WARNING "Divide by zero exception " \
							"in user mode\n");
			_exception(SIGILL, regs, FPE_INTDIV, addr);
			return;
		}
		printk(KERN_WARNING "Divide by zero exception " \
							"in kernel mode.\n");
		die("Divide by zero exception", regs, SIGBUS);
		break;
	case MICROBLAZE_FPU_EXCEPTION:
		pr_debug(KERN_WARNING "FPU exception\n");
		/* IEEE FP exception */
		/* I removed fsr variable and use code var for storing fsr */
		if (fsr & FSR_IO)
			fsr = FPE_FLTINV;
		else if (fsr & FSR_OF)
			fsr = FPE_FLTOVF;
		else if (fsr & FSR_UF)
			fsr = FPE_FLTUND;
		else if (fsr & FSR_DZ)
			fsr = FPE_FLTDIV;
		else if (fsr & FSR_DO)
			fsr = FPE_FLTRES;
		_exception(SIGFPE, regs, fsr, addr);
		break;

#ifdef CONFIG_MMU
	case MICROBLAZE_PRIVILEGED_EXCEPTION:
		pr_debug(KERN_WARNING "Privileged exception\n");
		/* "brk r0,r0" - used as debug breakpoint - old toolchain */
		if (get_user(code, (unsigned long *)regs->pc) == 0
			&& code == 0x980c0000) {
			_exception(SIGTRAP, regs, TRAP_BRKPT, addr);
		} else {
			_exception(SIGILL, regs, ILL_PRVOPC, addr);
		}
		break;
#endif
	default:
	/* FIXME what to do in unexpected exception */
		printk(KERN_WARNING "Unexpected exception %02x "
			"PC=%08x in %s mode\n", type, (unsigned int) addr,
			kernel_mode(regs) ? "kernel" : "user");
	}
	return;
}
Commit	Line	Data
c4df4bc1 MS	1	/*
	2	* HW exception handling
	3	*
	4	* Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
	5	* Copyright (C) 2008 PetaLogix
	6	*
	7	* This file is subject to the terms and conditions of the GNU General
	8	* Public License. See the file COPYING in the main directory of this
	9	* archive for more details.
	10	*/
	11
	12	/*
	13	* This file handles the architecture-dependent parts of hardware exceptions
	14	*/
	15
	16	#include <linux/kernel.h>
	17	#include <linux/signal.h>
	18	#include <linux/sched.h>
	19	#include <linux/kallsyms.h>
	20	#include <linux/module.h>
	21
	22	#include <asm/exceptions.h>
	23	#include <asm/entry.h> /* For KM CPU var */
4bb73c3d MS	24	#include <linux/uaccess.h>
	25	#include <linux/errno.h>
	26	#include <linux/ptrace.h>
c4df4bc1 MS	27	#include <asm/current.h>
	28
	29	#define MICROBLAZE_ILL_OPCODE_EXCEPTION 0x02
	30	#define MICROBLAZE_IBUS_EXCEPTION 0x03
	31	#define MICROBLAZE_DBUS_EXCEPTION 0x04
	32	#define MICROBLAZE_DIV_ZERO_EXCEPTION 0x05
	33	#define MICROBLAZE_FPU_EXCEPTION 0x06
4bb73c3d	34	#define MICROBLAZE_PRIVILEGED_EXCEPTION 0x07
c4df4bc1 MS	35
	36	static DEFINE_SPINLOCK(die_lock);
	37
	38	void die(const char str, struct pt_regs fp, long err)
	39	{
	40	console_verbose();
	41	spin_lock_irq(&die_lock);
	42	printk(KERN_WARNING "Oops: %s, sig: %ld\n", str, err);
	43	show_regs(fp);
	44	spin_unlock_irq(&die_lock);
	45	/* do_exit() should take care of panic'ing from an interrupt
	46	* context so we don't handle it here
	47	*/
	48	do_exit(err);
	49	}
	50
751f1605 MS	51	/* for user application debugging */
	52	void sw_exception(struct pt_regs *regs)
	53	{
	54	_exception(SIGTRAP, regs, TRAP_BRKPT, regs->r16);
	55	}
	56
c4df4bc1 MS	57	void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
	58	{
	59	siginfo_t info;
	60
	61	if (kernel_mode(regs)) {
c4df4bc1 MS	62	die("Exception in kernel mode", regs, signr);
	63	}
	64	info.si_signo = signr;
	65	info.si_errno = 0;
	66	info.si_code = code;
	67	info.si_addr = (void __user *) addr;
	68	force_sig_info(signr, &info, current);
	69	}
	70
	71	asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
	72	int fsr, int addr)
	73	{
4bb73c3d MS	74	#ifdef CONFIG_MMU
	75	int code;
	76	addr = regs->pc;
	77	#endif
	78
c4df4bc1	79	#if 0
bfc32ad0 MS	80	printk(KERN_WARNING "Exception %02x in %s mode, FSR=%08x PC=%08x " \
bfc32ad0 MS	81	"ESR=%08x\n",
c4df4bc1 MS	82	type, user_mode(regs) ? "user" : "kernel", fsr,
	83	(unsigned int) regs->pc, (unsigned int) regs->esr);
	84	#endif
	85
	86	switch (type & 0x1F) {
	87	case MICROBLAZE_ILL_OPCODE_EXCEPTION:
4bb73c3d	88	if (user_mode(regs)) {
bfc32ad0 MS	89	pr_debug(KERN_WARNING "Illegal opcode exception " \
bfc32ad0 MS	90	"in user mode.\n");
4bb73c3d MS	91	_exception(SIGILL, regs, ILL_ILLOPC, addr);
	92	return;
	93	}
bfc32ad0 MS	94	printk(KERN_WARNING "Illegal opcode exception " \
bfc32ad0 MS	95	"in kernel mode.\n");
4bb73c3d	96	die("opcode exception", regs, SIGBUS);
c4df4bc1 MS	97	break;
	98	case MICROBLAZE_IBUS_EXCEPTION:
	99	if (user_mode(regs)) {
bfc32ad0 MS	100	pr_debug(KERN_WARNING "Instruction bus error " \
bfc32ad0 MS	101	"exception in user mode.\n");
c4df4bc1 MS	102	_exception(SIGBUS, regs, BUS_ADRERR, addr);
	103	return;
	104	}
bfc32ad0 MS	105	printk(KERN_WARNING "Instruction bus error exception " \
bfc32ad0 MS	106	"in kernel mode.\n");
c4df4bc1 MS	107	die("bus exception", regs, SIGBUS);
	108	break;
	109	case MICROBLAZE_DBUS_EXCEPTION:
	110	if (user_mode(regs)) {
bfc32ad0 MS	111	pr_debug(KERN_WARNING "Data bus error exception " \
bfc32ad0 MS	112	"in user mode.\n");
c4df4bc1 MS	113	_exception(SIGBUS, regs, BUS_ADRERR, addr);
	114	return;
	115	}
bfc32ad0 MS	116	printk(KERN_WARNING "Data bus error exception " \
bfc32ad0 MS	117	"in kernel mode.\n");
c4df4bc1 MS	118	die("bus exception", regs, SIGBUS);
	119	break;
	120	case MICROBLAZE_DIV_ZERO_EXCEPTION:
4bb73c3d	121	if (user_mode(regs)) {
bfc32ad0 MS	122	pr_debug(KERN_WARNING "Divide by zero exception " \
bfc32ad0 MS	123	"in user mode\n");
23902d95	124	_exception(SIGILL, regs, FPE_INTDIV, addr);
4bb73c3d MS	125	return;
4bb73c3d MS	126	}
bfc32ad0 MS	127	printk(KERN_WARNING "Divide by zero exception " \
bfc32ad0 MS	128	"in kernel mode.\n");
f3ff8212	129	die("Divide by zero exception", regs, SIGBUS);
c4df4bc1	130	break;
c4df4bc1	131	case MICROBLAZE_FPU_EXCEPTION:
bfc32ad0	132	pr_debug(KERN_WARNING "FPU exception\n");
c4df4bc1 MS	133	/* IEEE FP exception */
	134	/* I removed fsr variable and use code var for storing fsr */
	135	if (fsr & FSR_IO)
	136	fsr = FPE_FLTINV;
	137	else if (fsr & FSR_OF)
	138	fsr = FPE_FLTOVF;
	139	else if (fsr & FSR_UF)
	140	fsr = FPE_FLTUND;
	141	else if (fsr & FSR_DZ)
	142	fsr = FPE_FLTDIV;
	143	else if (fsr & FSR_DO)
	144	fsr = FPE_FLTRES;
	145	_exception(SIGFPE, regs, fsr, addr);
	146	break;
	147
4bb73c3d MS	148	#ifdef CONFIG_MMU
4bb73c3d MS	149	case MICROBLAZE_PRIVILEGED_EXCEPTION:
bfc32ad0	150	pr_debug(KERN_WARNING "Privileged exception\n");
751f1605	151	/* "brk r0,r0" - used as debug breakpoint - old toolchain */
4bb73c3d MS	152	if (get_user(code, (unsigned long *)regs->pc) == 0
	153	&& code == 0x980c0000) {
	154	_exception(SIGTRAP, regs, TRAP_BRKPT, addr);
	155	} else {
	156	_exception(SIGILL, regs, ILL_PRVOPC, addr);
	157	}
	158	break;
	159	#endif
c4df4bc1	160	default:
4bb73c3d	161	/* FIXME what to do in unexpected exception */
c4df4bc1 MS	162	printk(KERN_WARNING "Unexpected exception %02x "
	163	"PC=%08x in %s mode\n", type, (unsigned int) addr,
	164	kernel_mode(regs) ? "kernel" : "user");
	165	}
	166	return;
	167	}