[deliverable/linux.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/export.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kallsyms.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>
#include <asm/cacheflush.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);
	pr_warn("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 */
asmlinkage void sw_exception(struct pt_regs *regs)
{
	_exception(SIGTRAP, regs, TRAP_BRKPT, regs->r16);
	flush_dcache_range(regs->r16, regs->r16 + 0x4);
	flush_icache_range(regs->r16, regs->r16 + 0x4);
}

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
	addr = regs->pc;
#endif

#if 0
	pr_warn("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("Illegal opcode exception in user mode\n");
			_exception(SIGILL, regs, ILL_ILLOPC, addr);
			return;
		}
		pr_warn("Illegal opcode exception in kernel mode.\n");
		die("opcode exception", regs, SIGBUS);
		break;
	case MICROBLAZE_IBUS_EXCEPTION:
		if (user_mode(regs)) {
			pr_debug("Instruction bus error exception in user mode\n");
			_exception(SIGBUS, regs, BUS_ADRERR, addr);
			return;
		}
		pr_warn("Instruction bus error exception in kernel mode.\n");
		die("bus exception", regs, SIGBUS);
		break;
	case MICROBLAZE_DBUS_EXCEPTION:
		if (user_mode(regs)) {
			pr_debug("Data bus error exception in user mode\n");
			_exception(SIGBUS, regs, BUS_ADRERR, addr);
			return;
		}
		pr_warn("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("Divide by zero exception in user mode\n");
			_exception(SIGFPE, regs, FPE_INTDIV, addr);
			return;
		}
		pr_warn("Divide by zero exception in kernel mode.\n");
		die("Divide by zero exception", regs, SIGBUS);
		break;
	case MICROBLAZE_FPU_EXCEPTION:
		pr_debug("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("Privileged exception\n");
		_exception(SIGILL, regs, ILL_PRVOPC, addr);
		break;
#endif
	default:
	/* FIXME what to do in unexpected exception */
		pr_warn("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
d64af918	16	#include <linux/export.h>
c4df4bc1 MS	17	#include <linux/kernel.h>
	18	#include <linux/signal.h>
	19	#include <linux/sched.h>
	20	#include <linux/kallsyms.h>
c4df4bc1 MS	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	27	#include <asm/current.h>
17b93146	28	#include <asm/cacheflush.h>
c4df4bc1 MS	29
	30	#define MICROBLAZE_ILL_OPCODE_EXCEPTION 0x02
	31	#define MICROBLAZE_IBUS_EXCEPTION 0x03
	32	#define MICROBLAZE_DBUS_EXCEPTION 0x04
	33	#define MICROBLAZE_DIV_ZERO_EXCEPTION 0x05
	34	#define MICROBLAZE_FPU_EXCEPTION 0x06
4bb73c3d	35	#define MICROBLAZE_PRIVILEGED_EXCEPTION 0x07
c4df4bc1 MS	36
	37	static DEFINE_SPINLOCK(die_lock);
	38
	39	void die(const char str, struct pt_regs fp, long err)
	40	{
	41	console_verbose();
	42	spin_lock_irq(&die_lock);
6bd55f0b	43	pr_warn("Oops: %s, sig: %ld\n", str, err);
c4df4bc1 MS	44	show_regs(fp);
	45	spin_unlock_irq(&die_lock);
	46	/* do_exit() should take care of panic'ing from an interrupt
	47	* context so we don't handle it here
	48	*/
	49	do_exit(err);
	50	}
	51
751f1605	52	/* for user application debugging */
f699980b	53	asmlinkage void sw_exception(struct pt_regs *regs)
751f1605 MS	54	{
751f1605 MS	55	_exception(SIGTRAP, regs, TRAP_BRKPT, regs->r16);
17b93146 MS	56	flush_dcache_range(regs->r16, regs->r16 + 0x4);
17b93146 MS	57	flush_icache_range(regs->r16, regs->r16 + 0x4);
751f1605 MS	58	}
751f1605 MS	59
c4df4bc1 MS	60	void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
	61	{
	62	siginfo_t info;
	63
6bd55f0b	64	if (kernel_mode(regs))
c4df4bc1	65	die("Exception in kernel mode", regs, signr);
6bd55f0b	66
c4df4bc1 MS	67	info.si_signo = signr;
	68	info.si_errno = 0;
	69	info.si_code = code;
	70	info.si_addr = (void __user *) addr;
	71	force_sig_info(signr, &info, current);
	72	}
	73
	74	asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
	75	int fsr, int addr)
	76	{
4bb73c3d	77	#ifdef CONFIG_MMU
4bb73c3d MS	78	addr = regs->pc;
	79	#endif
	80
c4df4bc1	81	#if 0
6bd55f0b	82	pr_warn("Exception %02x in %s mode, FSR=%08x PC=%08x ESR=%08x\n",
c4df4bc1 MS	83	type, user_mode(regs) ? "user" : "kernel", fsr,
	84	(unsigned int) regs->pc, (unsigned int) regs->esr);
	85	#endif
	86
	87	switch (type & 0x1F) {
	88	case MICROBLAZE_ILL_OPCODE_EXCEPTION:
4bb73c3d	89	if (user_mode(regs)) {
c4554c32	90	pr_debug("Illegal opcode exception in user mode\n");
4bb73c3d MS	91	_exception(SIGILL, regs, ILL_ILLOPC, addr);
	92	return;
	93	}
6bd55f0b	94	pr_warn("Illegal opcode exception in kernel mode.\n");
4bb73c3d	95	die("opcode exception", regs, SIGBUS);
c4df4bc1 MS	96	break;
	97	case MICROBLAZE_IBUS_EXCEPTION:
	98	if (user_mode(regs)) {
c4554c32	99	pr_debug("Instruction bus error exception in user mode\n");
c4df4bc1 MS	100	_exception(SIGBUS, regs, BUS_ADRERR, addr);
	101	return;
	102	}
6bd55f0b	103	pr_warn("Instruction bus error exception in kernel mode.\n");
c4df4bc1 MS	104	die("bus exception", regs, SIGBUS);
	105	break;
	106	case MICROBLAZE_DBUS_EXCEPTION:
	107	if (user_mode(regs)) {
c4554c32	108	pr_debug("Data bus error exception in user mode\n");
c4df4bc1 MS	109	_exception(SIGBUS, regs, BUS_ADRERR, addr);
	110	return;
	111	}
6bd55f0b	112	pr_warn("Data bus error exception in kernel mode.\n");
c4df4bc1 MS	113	die("bus exception", regs, SIGBUS);
	114	break;
	115	case MICROBLAZE_DIV_ZERO_EXCEPTION:
4bb73c3d	116	if (user_mode(regs)) {
c4554c32	117	pr_debug("Divide by zero exception in user mode\n");
15ec0908	118	_exception(SIGFPE, regs, FPE_INTDIV, addr);
4bb73c3d MS	119	return;
4bb73c3d MS	120	}
6bd55f0b	121	pr_warn("Divide by zero exception in kernel mode.\n");
f3ff8212	122	die("Divide by zero exception", regs, SIGBUS);
c4df4bc1	123	break;
c4df4bc1	124	case MICROBLAZE_FPU_EXCEPTION:
c4554c32	125	pr_debug("FPU exception\n");
c4df4bc1 MS	126	/* IEEE FP exception */
	127	/* I removed fsr variable and use code var for storing fsr */
	128	if (fsr & FSR_IO)
	129	fsr = FPE_FLTINV;
	130	else if (fsr & FSR_OF)
	131	fsr = FPE_FLTOVF;
	132	else if (fsr & FSR_UF)
	133	fsr = FPE_FLTUND;
	134	else if (fsr & FSR_DZ)
	135	fsr = FPE_FLTDIV;
	136	else if (fsr & FSR_DO)
	137	fsr = FPE_FLTRES;
	138	_exception(SIGFPE, regs, fsr, addr);
	139	break;
	140
4bb73c3d MS	141	#ifdef CONFIG_MMU
4bb73c3d MS	142	case MICROBLAZE_PRIVILEGED_EXCEPTION:
c4554c32	143	pr_debug("Privileged exception\n");
04256096	144	_exception(SIGILL, regs, ILL_PRVOPC, addr);
4bb73c3d MS	145	break;
4bb73c3d MS	146	#endif
c4df4bc1	147	default:
4bb73c3d	148	/* FIXME what to do in unexpected exception */
6bd55f0b MS	149	pr_warn("Unexpected exception %02x PC=%08x in %s mode\n",
6bd55f0b MS	150	type, (unsigned int) addr,
c4df4bc1 MS	151	kernel_mode(regs) ? "kernel" : "user");
	152	}
	153	return;
	154	}