[linux-2.6-block.git] / arch / xtensa / kernel / traps.c

/*
 * arch/xtensa/kernel/traps.c
 *
 * Exception handling.
 *
 * Derived from code with the following copyrights:
 * Copyright (C) 1994 - 1999 by Ralf Baechle
 * Modified for R3000 by Paul M. Antoine, 1995, 1996
 * Complete output from die() by Ulf Carlsson, 1998
 * Copyright (C) 1999 Silicon Graphics, Inc.
 *
 * Essentially rewritten for the Xtensa architecture port.
 *
 * Copyright (C) 2001 - 2013 Tensilica Inc.
 *
 * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
 * Chris Zankel	<chris@zankel.net>
 * Marc Gauthier<marc@tensilica.com, marc@alumni.uwaterloo.ca>
 * Kevin Chea
 *
 * 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.
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/stringify.h>
#include <linux/kallsyms.h>
#include <linux/delay.h>
#include <linux/hardirq.h>

#include <asm/stacktrace.h>
#include <asm/ptrace.h>
#include <asm/timex.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/traps.h>

/*
 * Machine specific interrupt handlers
 */

extern void kernel_exception(void);
extern void user_exception(void);

extern void fast_syscall_kernel(void);
extern void fast_syscall_user(void);
extern void fast_alloca(void);
extern void fast_unaligned(void);
extern void fast_second_level_miss(void);
extern void fast_store_prohibited(void);
extern void fast_coprocessor(void);

extern void do_illegal_instruction (struct pt_regs*);
extern void do_interrupt (struct pt_regs*);
extern void do_nmi(struct pt_regs *);
extern void do_unaligned_user (struct pt_regs*);
extern void do_multihit (struct pt_regs*, unsigned long);
extern void do_page_fault (struct pt_regs*, unsigned long);
extern void do_debug (struct pt_regs*);
extern void system_call (struct pt_regs*);

/*
 * The vector table must be preceded by a save area (which
 * implies it must be in RAM, unless one places RAM immediately
 * before a ROM and puts the vector at the start of the ROM (!))
 */

#define KRNL		0x01
#define USER		0x02

#define COPROCESSOR(x)							\
{ EXCCAUSE_COPROCESSOR ## x ## _DISABLED, USER, fast_coprocessor }

typedef struct {
	int cause;
	int fast;
	void* handler;
} dispatch_init_table_t;

static dispatch_init_table_t __initdata dispatch_init_table[] = {

{ EXCCAUSE_ILLEGAL_INSTRUCTION,	0,	   do_illegal_instruction},
{ EXCCAUSE_SYSTEM_CALL,		KRNL,	   fast_syscall_kernel },
{ EXCCAUSE_SYSTEM_CALL,		USER,	   fast_syscall_user },
{ EXCCAUSE_SYSTEM_CALL,		0,	   system_call },
/* EXCCAUSE_INSTRUCTION_FETCH unhandled */
/* EXCCAUSE_LOAD_STORE_ERROR unhandled*/
{ EXCCAUSE_LEVEL1_INTERRUPT,	0,	   do_interrupt },
{ EXCCAUSE_ALLOCA,		USER|KRNL, fast_alloca },
/* EXCCAUSE_INTEGER_DIVIDE_BY_ZERO unhandled */
/* EXCCAUSE_PRIVILEGED unhandled */
#if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION
#ifdef CONFIG_XTENSA_UNALIGNED_USER
{ EXCCAUSE_UNALIGNED,		USER,	   fast_unaligned },
#endif
{ EXCCAUSE_UNALIGNED,		0,	   do_unaligned_user },
{ EXCCAUSE_UNALIGNED,		KRNL,	   fast_unaligned },
#endif
#ifdef CONFIG_MMU
{ EXCCAUSE_ITLB_MISS,		0,	   do_page_fault },
{ EXCCAUSE_ITLB_MISS,		USER|KRNL, fast_second_level_miss},
{ EXCCAUSE_ITLB_MULTIHIT,		0,	   do_multihit },
{ EXCCAUSE_ITLB_PRIVILEGE,	0,	   do_page_fault },
/* EXCCAUSE_SIZE_RESTRICTION unhandled */
{ EXCCAUSE_FETCH_CACHE_ATTRIBUTE,	0,	   do_page_fault },
{ EXCCAUSE_DTLB_MISS,		USER|KRNL, fast_second_level_miss},
{ EXCCAUSE_DTLB_MISS,		0,	   do_page_fault },
{ EXCCAUSE_DTLB_MULTIHIT,		0,	   do_multihit },
{ EXCCAUSE_DTLB_PRIVILEGE,	0,	   do_page_fault },
/* EXCCAUSE_DTLB_SIZE_RESTRICTION unhandled */
{ EXCCAUSE_STORE_CACHE_ATTRIBUTE,	USER|KRNL, fast_store_prohibited },
{ EXCCAUSE_STORE_CACHE_ATTRIBUTE,	0,	   do_page_fault },
{ EXCCAUSE_LOAD_CACHE_ATTRIBUTE,	0,	   do_page_fault },
#endif /* CONFIG_MMU */
/* XCCHAL_EXCCAUSE_FLOATING_POINT unhandled */
#if XTENSA_HAVE_COPROCESSOR(0)
COPROCESSOR(0),
#endif
#if XTENSA_HAVE_COPROCESSOR(1)
COPROCESSOR(1),
#endif
#if XTENSA_HAVE_COPROCESSOR(2)
COPROCESSOR(2),
#endif
#if XTENSA_HAVE_COPROCESSOR(3)
COPROCESSOR(3),
#endif
#if XTENSA_HAVE_COPROCESSOR(4)
COPROCESSOR(4),
#endif
#if XTENSA_HAVE_COPROCESSOR(5)
COPROCESSOR(5),
#endif
#if XTENSA_HAVE_COPROCESSOR(6)
COPROCESSOR(6),
#endif
#if XTENSA_HAVE_COPROCESSOR(7)
COPROCESSOR(7),
#endif
#if XTENSA_FAKE_NMI
{ EXCCAUSE_MAPPED_NMI,			0,		do_nmi },
#endif
{ EXCCAUSE_MAPPED_DEBUG,		0,		do_debug },
{ -1, -1, 0 }

};

/* The exception table <exc_table> serves two functions:
 * 1. it contains three dispatch tables (fast_user, fast_kernel, default-c)
 * 2. it is a temporary memory buffer for the exception handlers.
 */

DEFINE_PER_CPU(unsigned long, exc_table[EXC_TABLE_SIZE/4]);

void die(const char*, struct pt_regs*, long);

static inline void
__die_if_kernel(const char *str, struct pt_regs *regs, long err)
{
	if (!user_mode(regs))
		die(str, regs, err);
}

/*
 * Unhandled Exceptions. Kill user task or panic if in kernel space.
 */

void do_unhandled(struct pt_regs *regs, unsigned long exccause)
{
	__die_if_kernel("Caught unhandled exception - should not happen",
	    		regs, SIGKILL);

	/* If in user mode, send SIGILL signal to current process */
	printk("Caught unhandled exception in '%s' "
	       "(pid = %d, pc = %#010lx) - should not happen\n"
	       "\tEXCCAUSE is %ld\n",
	       current->comm, task_pid_nr(current), regs->pc, exccause);
	force_sig(SIGILL, current);
}

/*
 * Multi-hit exception. This if fatal!
 */

void do_multihit(struct pt_regs *regs, unsigned long exccause)
{
	die("Caught multihit exception", regs, SIGKILL);
}

/*
 * IRQ handler.
 */

extern void do_IRQ(int, struct pt_regs *);

#if XTENSA_FAKE_NMI

#define IS_POW2(v) (((v) & ((v) - 1)) == 0)

#if !(PROFILING_INTLEVEL == XCHAL_EXCM_LEVEL && \
      IS_POW2(XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL)))
#warning "Fake NMI is requested for PMM, but there are other IRQs at or above its level."
#warning "Fake NMI will be used, but there will be a bugcheck if one of those IRQs fire."

static inline void check_valid_nmi(void)
{
	unsigned intread = get_sr(interrupt);
	unsigned intenable = get_sr(intenable);

	BUG_ON(intread & intenable &
	       ~(XTENSA_INTLEVEL_ANDBELOW_MASK(PROFILING_INTLEVEL) ^
		 XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL) ^
		 BIT(XCHAL_PROFILING_INTERRUPT)));
}

#else

static inline void check_valid_nmi(void)
{
}

#endif

irqreturn_t xtensa_pmu_irq_handler(int irq, void *dev_id);

DEFINE_PER_CPU(unsigned long, nmi_count);

void do_nmi(struct pt_regs *regs)
{
	struct pt_regs *old_regs;

	if ((regs->ps & PS_INTLEVEL_MASK) < LOCKLEVEL)
		trace_hardirqs_off();

	old_regs = set_irq_regs(regs);
	nmi_enter();
	++*this_cpu_ptr(&nmi_count);
	check_valid_nmi();
	xtensa_pmu_irq_handler(0, NULL);
	nmi_exit();
	set_irq_regs(old_regs);
}
#endif

void do_interrupt(struct pt_regs *regs)
{
	static const unsigned int_level_mask[] = {
		0,
		XCHAL_INTLEVEL1_MASK,
		XCHAL_INTLEVEL2_MASK,
		XCHAL_INTLEVEL3_MASK,
		XCHAL_INTLEVEL4_MASK,
		XCHAL_INTLEVEL5_MASK,
		XCHAL_INTLEVEL6_MASK,
		XCHAL_INTLEVEL7_MASK,
	};
	struct pt_regs *old_regs;

	trace_hardirqs_off();

	old_regs = set_irq_regs(regs);
	irq_enter();

	for (;;) {
		unsigned intread = get_sr(interrupt);
		unsigned intenable = get_sr(intenable);
		unsigned int_at_level = intread & intenable;
		unsigned level;

		for (level = LOCKLEVEL; level > 0; --level) {
			if (int_at_level & int_level_mask[level]) {
				int_at_level &= int_level_mask[level];
				break;
			}
		}

		if (level == 0)
			break;

		do_IRQ(__ffs(int_at_level), regs);
	}

	irq_exit();
	set_irq_regs(old_regs);
}

/*
 * Illegal instruction. Fatal if in kernel space.
 */

void
do_illegal_instruction(struct pt_regs *regs)
{
	__die_if_kernel("Illegal instruction in kernel", regs, SIGKILL);

	/* If in user mode, send SIGILL signal to current process. */

	printk("Illegal Instruction in '%s' (pid = %d, pc = %#010lx)\n",
	    current->comm, task_pid_nr(current), regs->pc);
	force_sig(SIGILL, current);
}


/*
 * Handle unaligned memory accesses from user space. Kill task.
 *
 * If CONFIG_UNALIGNED_USER is not set, we don't allow unaligned memory
 * accesses causes from user space.
 */

#if XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION
void
do_unaligned_user (struct pt_regs *regs)
{
	siginfo_t info;

	__die_if_kernel("Unhandled unaligned exception in kernel",
	    		regs, SIGKILL);

	current->thread.bad_vaddr = regs->excvaddr;
	current->thread.error_code = -3;
	printk("Unaligned memory access to %08lx in '%s' "
	       "(pid = %d, pc = %#010lx)\n",
	       regs->excvaddr, current->comm, task_pid_nr(current), regs->pc);
	info.si_signo = SIGBUS;
	info.si_errno = 0;
	info.si_code = BUS_ADRALN;
	info.si_addr = (void *) regs->excvaddr;
	force_sig_info(SIGSEGV, &info, current);

}
#endif

void
do_debug(struct pt_regs *regs)
{
	__die_if_kernel("Breakpoint in kernel", regs, SIGKILL);

	/* If in user mode, send SIGTRAP signal to current process */

	force_sig(SIGTRAP, current);
}


static void set_handler(int idx, void *handler)
{
	unsigned int cpu;

	for_each_possible_cpu(cpu)
		per_cpu(exc_table, cpu)[idx] = (unsigned long)handler;
}

/* Set exception C handler - for temporary use when probing exceptions */

void * __init trap_set_handler(int cause, void *handler)
{
	void *previous = (void *)per_cpu(exc_table, 0)[
		EXC_TABLE_DEFAULT / 4 + cause];
	set_handler(EXC_TABLE_DEFAULT / 4 + cause, handler);
	return previous;
}


static void trap_init_excsave(void)
{
	unsigned long excsave1 = (unsigned long)this_cpu_ptr(exc_table);
	__asm__ __volatile__("wsr  %0, excsave1\n" : : "a" (excsave1));
}

/*
 * Initialize dispatch tables.
 *
 * The exception vectors are stored compressed the __init section in the
 * dispatch_init_table. This function initializes the following three tables
 * from that compressed table:
 * - fast user		first dispatch table for user exceptions
 * - fast kernel	first dispatch table for kernel exceptions
 * - default C-handler	C-handler called by the default fast handler.
 *
 * See vectors.S for more details.
 */

void __init trap_init(void)
{
	int i;

	/* Setup default vectors. */

	for(i = 0; i < 64; i++) {
		set_handler(EXC_TABLE_FAST_USER/4   + i, user_exception);
		set_handler(EXC_TABLE_FAST_KERNEL/4 + i, kernel_exception);
		set_handler(EXC_TABLE_DEFAULT/4 + i, do_unhandled);
	}

	/* Setup specific handlers. */

	for(i = 0; dispatch_init_table[i].cause >= 0; i++) {

		int fast = dispatch_init_table[i].fast;
		int cause = dispatch_init_table[i].cause;
		void *handler = dispatch_init_table[i].handler;

		if (fast == 0)
			set_handler (EXC_TABLE_DEFAULT/4 + cause, handler);
		if (fast && fast & USER)
			set_handler (EXC_TABLE_FAST_USER/4 + cause, handler);
		if (fast && fast & KRNL)
			set_handler (EXC_TABLE_FAST_KERNEL/4 + cause, handler);
	}

	/* Initialize EXCSAVE_1 to hold the address of the exception table. */
	trap_init_excsave();
}

#ifdef CONFIG_SMP
void secondary_trap_init(void)
{
	trap_init_excsave();
}
#endif

/*
 * This function dumps the current valid window frame and other base registers.
 */

void show_regs(struct pt_regs * regs)
{
	int i, wmask;

	show_regs_print_info(KERN_DEFAULT);

	wmask = regs->wmask & ~1;

	for (i = 0; i < 16; i++) {
		if ((i % 8) == 0)
			printk(KERN_INFO "a%02d:", i);
		printk(KERN_CONT " %08lx", regs->areg[i]);
	}
	printk(KERN_CONT "\n");

	printk("pc: %08lx, ps: %08lx, depc: %08lx, excvaddr: %08lx\n",
	       regs->pc, regs->ps, regs->depc, regs->excvaddr);
	printk("lbeg: %08lx, lend: %08lx lcount: %08lx, sar: %08lx\n",
	       regs->lbeg, regs->lend, regs->lcount, regs->sar);
	if (user_mode(regs))
		printk("wb: %08lx, ws: %08lx, wmask: %08lx, syscall: %ld\n",
		       regs->windowbase, regs->windowstart, regs->wmask,
		       regs->syscall);
}

static int show_trace_cb(struct stackframe *frame, void *data)
{
	if (kernel_text_address(frame->pc)) {
		printk(" [<%08lx>] ", frame->pc);
		print_symbol("%s\n", frame->pc);
	}
	return 0;
}

void show_trace(struct task_struct *task, unsigned long *sp)
{
	if (!sp)
		sp = stack_pointer(task);

	printk("Call Trace:");
#ifdef CONFIG_KALLSYMS
	printk("\n");
#endif
	walk_stackframe(sp, show_trace_cb, NULL);
	printk("\n");
}

/*
 * This routine abuses get_user()/put_user() to reference pointers
 * with at least a bit of error checking ...
 */

static int kstack_depth_to_print = 24;

void show_stack(struct task_struct *task, unsigned long *sp)
{
	int i = 0;
	unsigned long *stack;

	if (!sp)
		sp = stack_pointer(task);
	stack = sp;

	printk("\nStack: ");

	for (i = 0; i < kstack_depth_to_print; i++) {
		if (kstack_end(sp))
			break;
		if (i && ((i % 8) == 0))
			printk("\n       ");
		printk("%08lx ", *sp++);
	}
	printk("\n");
	show_trace(task, stack);
}

void show_code(unsigned int *pc)
{
	long i;

	printk("\nCode:");

	for(i = -3 ; i < 6 ; i++) {
		unsigned long insn;
		if (__get_user(insn, pc + i)) {
			printk(" (Bad address in pc)\n");
			break;
		}
		printk("%c%08lx%c",(i?' ':'<'),insn,(i?' ':'>'));
	}
}

DEFINE_SPINLOCK(die_lock);

void die(const char * str, struct pt_regs * regs, long err)
{
	static int die_counter;
	int nl = 0;

	console_verbose();
	spin_lock_irq(&die_lock);

	printk("%s: sig: %ld [#%d]\n", str, err, ++die_counter);
#ifdef CONFIG_PREEMPT
	printk("PREEMPT ");
	nl = 1;
#endif
	if (nl)
		printk("\n");
	show_regs(regs);
	if (!user_mode(regs))
		show_stack(NULL, (unsigned long*)regs->areg[1]);

	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
	spin_unlock_irq(&die_lock);

	if (in_interrupt())
		panic("Fatal exception in interrupt");

	if (panic_on_oops)
		panic("Fatal exception");

	do_exit(err);
}
Commit	Line	Data
5a0015d6 CZ	1	/*
	2	* arch/xtensa/kernel/traps.c
	3	*
	4	* Exception handling.
	5	*
	6	* Derived from code with the following copyrights:
	7	* Copyright (C) 1994 - 1999 by Ralf Baechle
	8	* Modified for R3000 by Paul M. Antoine, 1995, 1996
	9	* Complete output from die() by Ulf Carlsson, 1998
	10	* Copyright (C) 1999 Silicon Graphics, Inc.
	11	*
	12	* Essentially rewritten for the Xtensa architecture port.
	13	*
3e4196a5	14	* Copyright (C) 2001 - 2013 Tensilica Inc.
5a0015d6 CZ	15	*
	16	* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
	17	* Chris Zankel <chris@zankel.net>
	18	* Marc Gauthier<marc@tensilica.com, marc@alumni.uwaterloo.ca>
	19	* Kevin Chea
	20	*
	21	* This file is subject to the terms and conditions of the GNU General Public
	22	* License. See the file "COPYING" in the main directory of this archive
	23	* for more details.
	24	*/
	25
	26	#include <linux/kernel.h>
	27	#include <linux/sched.h>
	28	#include <linux/init.h>
	29	#include <linux/module.h>
	30	#include <linux/stringify.h>
	31	#include <linux/kallsyms.h>
5c888d53	32	#include <linux/delay.h>
5a891ed5	33	#include <linux/hardirq.h>
5a0015d6	34
3e4196a5	35	#include <asm/stacktrace.h>
5a0015d6 CZ	36	#include <asm/ptrace.h>
	37	#include <asm/timex.h>
	38	#include <asm/uaccess.h>
	39	#include <asm/pgtable.h>
	40	#include <asm/processor.h>
2d6f82fe	41	#include <asm/traps.h>
5a0015d6	42
5a0015d6 CZ	43	/*
	44	* Machine specific interrupt handlers
	45	*/
	46
	47	extern void kernel_exception(void);
	48	extern void user_exception(void);
	49
	50	extern void fast_syscall_kernel(void);
	51	extern void fast_syscall_user(void);
	52	extern void fast_alloca(void);
	53	extern void fast_unaligned(void);
	54	extern void fast_second_level_miss(void);
	55	extern void fast_store_prohibited(void);
	56	extern void fast_coprocessor(void);
	57
	58	extern void do_illegal_instruction (struct pt_regs*);
	59	extern void do_interrupt (struct pt_regs*);
38fef73c	60	extern void do_nmi(struct pt_regs *);
5a0015d6 CZ	61	extern void do_unaligned_user (struct pt_regs*);
	62	extern void do_multihit (struct pt_regs*, unsigned long);
	63	extern void do_page_fault (struct pt_regs*, unsigned long);
	64	extern void do_debug (struct pt_regs*);
	65	extern void system_call (struct pt_regs*);
	66
	67	/*
	68	* The vector table must be preceded by a save area (which
	69	* implies it must be in RAM, unless one places RAM immediately
	70	* before a ROM and puts the vector at the start of the ROM (!))
	71	*/
	72
	73	#define KRNL 0x01
	74	#define USER 0x02
	75
	76	#define COPROCESSOR(x) \
173d6681	77	{ EXCCAUSE_COPROCESSOR ## x ## _DISABLED, USER, fast_coprocessor }
5a0015d6 CZ	78
	79	typedef struct {
	80	int cause;
	81	int fast;
	82	void* handler;
	83	} dispatch_init_table_t;
	84
b91dc336	85	static dispatch_init_table_t __initdata dispatch_init_table[] = {
5a0015d6	86
173d6681 CZ	87	{ EXCCAUSE_ILLEGAL_INSTRUCTION, 0, do_illegal_instruction},
	88	{ EXCCAUSE_SYSTEM_CALL, KRNL, fast_syscall_kernel },
	89	{ EXCCAUSE_SYSTEM_CALL, USER, fast_syscall_user },
	90	{ EXCCAUSE_SYSTEM_CALL, 0, system_call },
	91	/* EXCCAUSE_INSTRUCTION_FETCH unhandled */
	92	/* EXCCAUSE_LOAD_STORE_ERROR unhandled*/
	93	{ EXCCAUSE_LEVEL1_INTERRUPT, 0, do_interrupt },
	94	{ EXCCAUSE_ALLOCA, USER\|KRNL, fast_alloca },
	95	/* EXCCAUSE_INTEGER_DIVIDE_BY_ZERO unhandled */
	96	/* EXCCAUSE_PRIVILEGED unhandled */
5a0015d6	97	#if XCHAL_UNALIGNED_LOAD_EXCEPTION \|\| XCHAL_UNALIGNED_STORE_EXCEPTION
4ded6282	98	#ifdef CONFIG_XTENSA_UNALIGNED_USER
173d6681	99	{ EXCCAUSE_UNALIGNED, USER, fast_unaligned },
5a0015d6	100	#endif
3cfc096e	101	{ EXCCAUSE_UNALIGNED, 0, do_unaligned_user },
173d6681	102	{ EXCCAUSE_UNALIGNED, KRNL, fast_unaligned },
5a0015d6	103	#endif
e5083a63	104	#ifdef CONFIG_MMU
173d6681 CZ	105	{ EXCCAUSE_ITLB_MISS, 0, do_page_fault },
	106	{ EXCCAUSE_ITLB_MISS, USER\|KRNL, fast_second_level_miss},
	107	{ EXCCAUSE_ITLB_MULTIHIT, 0, do_multihit },
	108	{ EXCCAUSE_ITLB_PRIVILEGE, 0, do_page_fault },
	109	/* EXCCAUSE_SIZE_RESTRICTION unhandled */
	110	{ EXCCAUSE_FETCH_CACHE_ATTRIBUTE, 0, do_page_fault },
	111	{ EXCCAUSE_DTLB_MISS, USER\|KRNL, fast_second_level_miss},
	112	{ EXCCAUSE_DTLB_MISS, 0, do_page_fault },
	113	{ EXCCAUSE_DTLB_MULTIHIT, 0, do_multihit },
	114	{ EXCCAUSE_DTLB_PRIVILEGE, 0, do_page_fault },
	115	/* EXCCAUSE_DTLB_SIZE_RESTRICTION unhandled */
	116	{ EXCCAUSE_STORE_CACHE_ATTRIBUTE, USER\|KRNL, fast_store_prohibited },
	117	{ EXCCAUSE_STORE_CACHE_ATTRIBUTE, 0, do_page_fault },
	118	{ EXCCAUSE_LOAD_CACHE_ATTRIBUTE, 0, do_page_fault },
e5083a63	119	#endif /* CONFIG_MMU */
5a0015d6	120	/* XCCHAL_EXCCAUSE_FLOATING_POINT unhandled */
c658eac6	121	#if XTENSA_HAVE_COPROCESSOR(0)
5a0015d6 CZ	122	COPROCESSOR(0),
5a0015d6 CZ	123	#endif
c658eac6	124	#if XTENSA_HAVE_COPROCESSOR(1)
5a0015d6 CZ	125	COPROCESSOR(1),
5a0015d6 CZ	126	#endif
c658eac6	127	#if XTENSA_HAVE_COPROCESSOR(2)
5a0015d6 CZ	128	COPROCESSOR(2),
5a0015d6 CZ	129	#endif
c658eac6	130	#if XTENSA_HAVE_COPROCESSOR(3)
5a0015d6 CZ	131	COPROCESSOR(3),
5a0015d6 CZ	132	#endif
c658eac6	133	#if XTENSA_HAVE_COPROCESSOR(4)
5a0015d6 CZ	134	COPROCESSOR(4),
5a0015d6 CZ	135	#endif
c658eac6	136	#if XTENSA_HAVE_COPROCESSOR(5)
5a0015d6 CZ	137	COPROCESSOR(5),
5a0015d6 CZ	138	#endif
c658eac6	139	#if XTENSA_HAVE_COPROCESSOR(6)
5a0015d6 CZ	140	COPROCESSOR(6),
5a0015d6 CZ	141	#endif
c658eac6	142	#if XTENSA_HAVE_COPROCESSOR(7)
5a0015d6 CZ	143	COPROCESSOR(7),
5a0015d6 CZ	144	#endif
38fef73c MF	145	#if XTENSA_FAKE_NMI
	146	{ EXCCAUSE_MAPPED_NMI, 0, do_nmi },
	147	#endif
5a0015d6 CZ	148	{ EXCCAUSE_MAPPED_DEBUG, 0, do_debug },
	149	{ -1, -1, 0 }
	150
	151	};
	152
	153	/* The exception table <exc_table> serves two functions:
	154	* 1. it contains three dispatch tables (fast_user, fast_kernel, default-c)
	155	* 2. it is a temporary memory buffer for the exception handlers.
	156	*/
	157
f615136c	158	DEFINE_PER_CPU(unsigned long, exc_table[EXC_TABLE_SIZE/4]);
5a0015d6 CZ	159
	160	void die(const char, struct pt_regs, long);
	161
	162	static inline void
	163	__die_if_kernel(const char str, struct pt_regs regs, long err)
	164	{
	165	if (!user_mode(regs))
	166	die(str, regs, err);
	167	}
	168
	169	/*
	170	* Unhandled Exceptions. Kill user task or panic if in kernel space.
	171	*/
	172
	173	void do_unhandled(struct pt_regs *regs, unsigned long exccause)
	174	{
	175	__die_if_kernel("Caught unhandled exception - should not happen",
	176	regs, SIGKILL);
	177
	178	/* If in user mode, send SIGILL signal to current process */
	179	printk("Caught unhandled exception in '%s' "
	180	"(pid = %d, pc = %#010lx) - should not happen\n"
	181	"\tEXCCAUSE is %ld\n",
19c5870c	182	current->comm, task_pid_nr(current), regs->pc, exccause);
5a0015d6 CZ	183	force_sig(SIGILL, current);
	184	}
	185
	186	/*
	187	* Multi-hit exception. This if fatal!
	188	*/
	189
	190	void do_multihit(struct pt_regs *regs, unsigned long exccause)
	191	{
	192	die("Caught multihit exception", regs, SIGKILL);
	193	}
	194
	195	/*
2d1c645c	196	* IRQ handler.
5a0015d6 CZ	197	*/
5a0015d6 CZ	198
5a0015d6 CZ	199	extern void do_IRQ(int, struct pt_regs *);
5a0015d6 CZ	200
38fef73c MF	201	#if XTENSA_FAKE_NMI
38fef73c MF	202
e4629194 MF	203	#define IS_POW2(v) (((v) & ((v) - 1)) == 0)
	204
	205	#if !(PROFILING_INTLEVEL == XCHAL_EXCM_LEVEL && \
	206	IS_POW2(XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL)))
	207	#warning "Fake NMI is requested for PMM, but there are other IRQs at or above its level."
	208	#warning "Fake NMI will be used, but there will be a bugcheck if one of those IRQs fire."
	209
	210	static inline void check_valid_nmi(void)
	211	{
	212	unsigned intread = get_sr(interrupt);
	213	unsigned intenable = get_sr(intenable);
	214
	215	BUG_ON(intread & intenable &
	216	~(XTENSA_INTLEVEL_ANDBELOW_MASK(PROFILING_INTLEVEL) ^
	217	XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL) ^
	218	BIT(XCHAL_PROFILING_INTERRUPT)));
	219	}
	220
	221	#else
	222
	223	static inline void check_valid_nmi(void)
	224	{
	225	}
	226
	227	#endif
	228
38fef73c MF	229	irqreturn_t xtensa_pmu_irq_handler(int irq, void *dev_id);
	230
	231	DEFINE_PER_CPU(unsigned long, nmi_count);
	232
	233	void do_nmi(struct pt_regs *regs)
	234	{
	235	struct pt_regs *old_regs;
	236
	237	if ((regs->ps & PS_INTLEVEL_MASK) < LOCKLEVEL)
	238	trace_hardirqs_off();
	239
	240	old_regs = set_irq_regs(regs);
	241	nmi_enter();
	242	++*this_cpu_ptr(&nmi_count);
e4629194	243	check_valid_nmi();
38fef73c MF	244	xtensa_pmu_irq_handler(0, NULL);
	245	nmi_exit();
	246	set_irq_regs(old_regs);
	247	}
	248	#endif
	249
2d1c645c	250	void do_interrupt(struct pt_regs *regs)
5a0015d6	251	{
2d1c645c MG	252	static const unsigned int_level_mask[] = {
	253	0,
	254	XCHAL_INTLEVEL1_MASK,
	255	XCHAL_INTLEVEL2_MASK,
	256	XCHAL_INTLEVEL3_MASK,
	257	XCHAL_INTLEVEL4_MASK,
	258	XCHAL_INTLEVEL5_MASK,
	259	XCHAL_INTLEVEL6_MASK,
	260	XCHAL_INTLEVEL7_MASK,
	261	};
7d5f6a9a	262	struct pt_regs *old_regs;
99623239	263
7d5f6a9a MF	264	trace_hardirqs_off();
	265
	266	old_regs = set_irq_regs(regs);
99623239	267	irq_enter();
5a0015d6	268
2d1c645c MG	269	for (;;) {
	270	unsigned intread = get_sr(interrupt);
	271	unsigned intenable = get_sr(intenable);
895666a9 MF	272	unsigned int_at_level = intread & intenable;
	273	unsigned level;
	274
	275	for (level = LOCKLEVEL; level > 0; --level) {
	276	if (int_at_level & int_level_mask[level]) {
	277	int_at_level &= int_level_mask[level];
	278	break;
	279	}
	280	}
2d1c645c	281
895666a9	282	if (level == 0)
99623239 MF	283	break;
	284
	285	do_IRQ(__ffs(int_at_level), regs);
5a0015d6	286	}
99623239 MF	287
	288	irq_exit();
	289	set_irq_regs(old_regs);
5a0015d6 CZ	290	}
	291
	292	/*
	293	* Illegal instruction. Fatal if in kernel space.
	294	*/
	295
	296	void
	297	do_illegal_instruction(struct pt_regs *regs)
	298	{
	299	__die_if_kernel("Illegal instruction in kernel", regs, SIGKILL);
	300
	301	/* If in user mode, send SIGILL signal to current process. */
	302
	303	printk("Illegal Instruction in '%s' (pid = %d, pc = %#010lx)\n",
19c5870c	304	current->comm, task_pid_nr(current), regs->pc);
5a0015d6 CZ	305	force_sig(SIGILL, current);
	306	}
	307
	308
	309	/*
	310	* Handle unaligned memory accesses from user space. Kill task.
	311	*
	312	* If CONFIG_UNALIGNED_USER is not set, we don't allow unaligned memory
	313	* accesses causes from user space.
	314	*/
	315
	316	#if XCHAL_UNALIGNED_LOAD_EXCEPTION \|\| XCHAL_UNALIGNED_STORE_EXCEPTION
5a0015d6 CZ	317	void
	318	do_unaligned_user (struct pt_regs *regs)
	319	{
	320	siginfo_t info;
	321
	322	__die_if_kernel("Unhandled unaligned exception in kernel",
	323	regs, SIGKILL);
	324
	325	current->thread.bad_vaddr = regs->excvaddr;
	326	current->thread.error_code = -3;
	327	printk("Unaligned memory access to %08lx in '%s' "
	328	"(pid = %d, pc = %#010lx)\n",
19c5870c	329	regs->excvaddr, current->comm, task_pid_nr(current), regs->pc);
5a0015d6 CZ	330	info.si_signo = SIGBUS;
	331	info.si_errno = 0;
	332	info.si_code = BUS_ADRALN;
	333	info.si_addr = (void *) regs->excvaddr;
	334	force_sig_info(SIGSEGV, &info, current);
	335
	336	}
	337	#endif
5a0015d6 CZ	338
	339	void
	340	do_debug(struct pt_regs *regs)
	341	{
5a0015d6 CZ	342	__die_if_kernel("Breakpoint in kernel", regs, SIGKILL);
	343
	344	/* If in user mode, send SIGTRAP signal to current process */
	345
	346	force_sig(SIGTRAP, current);
	347	}
	348
	349
f615136c MF	350	static void set_handler(int idx, void *handler)
	351	{
	352	unsigned int cpu;
	353
	354	for_each_possible_cpu(cpu)
	355	per_cpu(exc_table, cpu)[idx] = (unsigned long)handler;
	356	}
	357
28570e8d MF	358	/* Set exception C handler - for temporary use when probing exceptions */
	359
	360	void * __init trap_set_handler(int cause, void *handler)
	361	{
f615136c MF	362	void previous = (void )per_cpu(exc_table, 0)[
	363	EXC_TABLE_DEFAULT / 4 + cause];
	364	set_handler(EXC_TABLE_DEFAULT / 4 + cause, handler);
28570e8d MF	365	return previous;
	366	}
	367
	368
49b424fe	369	static void trap_init_excsave(void)
f615136c MF	370	{
	371	unsigned long excsave1 = (unsigned long)this_cpu_ptr(exc_table);
	372	__asm__ __volatile__("wsr %0, excsave1\n" : : "a" (excsave1));
	373	}
	374
5a0015d6 CZ	375	/*
	376	* Initialize dispatch tables.
	377	*
	378	* The exception vectors are stored compressed the __init section in the
	379	* dispatch_init_table. This function initializes the following three tables
	380	* from that compressed table:
	381	* - fast user first dispatch table for user exceptions
	382	* - fast kernel first dispatch table for kernel exceptions
	383	* - default C-handler C-handler called by the default fast handler.
	384	*
	385	* See vectors.S for more details.
	386	*/
	387
b91dc336	388	void __init trap_init(void)
5a0015d6 CZ	389	{
	390	int i;
	391
	392	/* Setup default vectors. */
	393
	394	for(i = 0; i < 64; i++) {
	395	set_handler(EXC_TABLE_FAST_USER/4 + i, user_exception);
	396	set_handler(EXC_TABLE_FAST_KERNEL/4 + i, kernel_exception);
	397	set_handler(EXC_TABLE_DEFAULT/4 + i, do_unhandled);
	398	}
	399
	400	/* Setup specific handlers. */
	401
	402	for(i = 0; dispatch_init_table[i].cause >= 0; i++) {
	403
	404	int fast = dispatch_init_table[i].fast;
	405	int cause = dispatch_init_table[i].cause;
	406	void *handler = dispatch_init_table[i].handler;
	407
	408	if (fast == 0)
	409	set_handler (EXC_TABLE_DEFAULT/4 + cause, handler);
	410	if (fast && fast & USER)
	411	set_handler (EXC_TABLE_FAST_USER/4 + cause, handler);
	412	if (fast && fast & KRNL)
	413	set_handler (EXC_TABLE_FAST_KERNEL/4 + cause, handler);
	414	}
	415
	416	/* Initialize EXCSAVE_1 to hold the address of the exception table. */
f615136c MF	417	trap_init_excsave();
f615136c MF	418	}
5a0015d6	419
f615136c	420	#ifdef CONFIG_SMP
49b424fe	421	void secondary_trap_init(void)
f615136c MF	422	{
f615136c MF	423	trap_init_excsave();
5a0015d6	424	}
f615136c	425	#endif
5a0015d6 CZ	426
	427	/*
	428	* This function dumps the current valid window frame and other base registers.
	429	*/
	430
	431	void show_regs(struct pt_regs * regs)
	432	{
	433	int i, wmask;
	434
a43cb95d TH	435	show_regs_print_info(KERN_DEFAULT);
a43cb95d TH	436
5a0015d6 CZ	437	wmask = regs->wmask & ~1;
5a0015d6 CZ	438
8d7e8240	439	for (i = 0; i < 16; i++) {
5a0015d6	440	if ((i % 8) == 0)
ad361c98 JP	441	printk(KERN_INFO "a%02d:", i);
ad361c98 JP	442	printk(KERN_CONT " %08lx", regs->areg[i]);
5a0015d6	443	}
ad361c98	444	printk(KERN_CONT "\n");
5a0015d6 CZ	445
	446	printk("pc: %08lx, ps: %08lx, depc: %08lx, excvaddr: %08lx\n",
	447	regs->pc, regs->ps, regs->depc, regs->excvaddr);
	448	printk("lbeg: %08lx, lend: %08lx lcount: %08lx, sar: %08lx\n",
	449	regs->lbeg, regs->lend, regs->lcount, regs->sar);
	450	if (user_mode(regs))
	451	printk("wb: %08lx, ws: %08lx, wmask: %08lx, syscall: %ld\n",
	452	regs->windowbase, regs->windowstart, regs->wmask,
	453	regs->syscall);
	454	}
	455
3e4196a5	456	static int show_trace_cb(struct stackframe frame, void data)
586411dc	457	{
3e4196a5 MF	458	if (kernel_text_address(frame->pc)) {
	459	printk(" [<%08lx>] ", frame->pc);
	460	print_symbol("%s\n", frame->pc);
	461	}
	462	return 0;
586411dc JW	463	}
586411dc JW	464
5a0015d6 CZ	465	void show_trace(struct task_struct task, unsigned long sp)
5a0015d6 CZ	466	{
3e4196a5 MF	467	if (!sp)
3e4196a5 MF	468	sp = stack_pointer(task);
5a0015d6 CZ	469
	470	printk("Call Trace:");
	471	#ifdef CONFIG_KALLSYMS
	472	printk("\n");
	473	#endif
3e4196a5	474	walk_stackframe(sp, show_trace_cb, NULL);
5a0015d6 CZ	475	printk("\n");
	476	}
	477
	478	/*
	479	* This routine abuses get_user()/put_user() to reference pointers
	480	* with at least a bit of error checking ...
	481	*/
	482
	483	static int kstack_depth_to_print = 24;
	484
	485	void show_stack(struct task_struct task, unsigned long sp)
	486	{
	487	int i = 0;
	488	unsigned long *stack;
	489
28a0ce7f	490	if (!sp)
586411dc	491	sp = stack_pointer(task);
c4c4594b	492	stack = sp;
5a0015d6 CZ	493
	494	printk("\nStack: ");
	495
	496	for (i = 0; i < kstack_depth_to_print; i++) {
	497	if (kstack_end(sp))
	498	break;
	499	if (i && ((i % 8) == 0))
	500	printk("\n ");
	501	printk("%08lx ", *sp++);
	502	}
	503	printk("\n");
	504	show_trace(task, stack);
	505	}
	506
5a0015d6 CZ	507	void show_code(unsigned int *pc)
	508	{
	509	long i;
	510
	511	printk("\nCode:");
	512
	513	for(i = -3 ; i < 6 ; i++) {
	514	unsigned long insn;
	515	if (__get_user(insn, pc + i)) {
	516	printk(" (Bad address in pc)\n");
	517	break;
	518	}
	519	printk("%c%08lx%c",(i?' ':'<'),insn,(i?' ':'>'));
	520	}
	521	}
	522
34af946a	523	DEFINE_SPINLOCK(die_lock);
5a0015d6 CZ	524
	525	void die(const char * str, struct pt_regs * regs, long err)
	526	{
	527	static int die_counter;
	528	int nl = 0;
	529
	530	console_verbose();
	531	spin_lock_irq(&die_lock);
	532
	533	printk("%s: sig: %ld [#%d]\n", str, err, ++die_counter);
	534	#ifdef CONFIG_PREEMPT
	535	printk("PREEMPT ");
	536	nl = 1;
	537	#endif
	538	if (nl)
	539	printk("\n");
	540	show_regs(regs);
	541	if (!user_mode(regs))
	542	show_stack(NULL, (unsigned long*)regs->areg[1]);
	543
373d4d09	544	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
5a0015d6 CZ	545	spin_unlock_irq(&die_lock);
	546
	547	if (in_interrupt())
	548	panic("Fatal exception in interrupt");
	549
cea6a4ba	550	if (panic_on_oops)
012c437d	551	panic("Fatal exception");
cea6a4ba	552
5a0015d6 CZ	553	do_exit(err);
5a0015d6 CZ	554	}