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/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/bug.h>
#include <linux/init.h>
#include <linux/kallsyms.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <asm/addrspace.h>
#include <asm/mmu_context.h>
#include <asm/ocd.h>
#include <asm/sysreg.h>
#include <asm/traps.h>
static DEFINE_SPINLOCK(die_lock);
void NORET_TYPE die(const char *str, struct pt_regs *regs, long err)
{
static int die_counter;
console_verbose();
spin_lock_irq(&die_lock);
bust_spinlocks(1);
printk(KERN_ALERT "Oops: %s, sig: %ld [#%d]\n" KERN_EMERG,
str, err, ++die_counter);
#ifdef CONFIG_PREEMPT
printk("PREEMPT ");
#endif
#ifdef CONFIG_FRAME_POINTER
printk("FRAME_POINTER ");
#endif
if (current_cpu_data.features & AVR32_FEATURE_OCD) {
unsigned long did = __mfdr(DBGREG_DID);
printk("chip: 0x%03lx:0x%04lx rev %lu\n",
(did >> 1) & 0x7ff,
(did >> 12) & 0x7fff,
(did >> 28) & 0xf);
} else {
printk("cpu: arch %u r%u / core %u r%u\n",
current_cpu_data.arch_type,
current_cpu_data.arch_revision,
current_cpu_data.cpu_type,
current_cpu_data.cpu_revision);
}
print_modules();
show_regs_log_lvl(regs, KERN_EMERG);
show_stack_log_lvl(current, regs->sp, regs, KERN_EMERG);
bust_spinlocks(0);
spin_unlock_irq(&die_lock);
if (in_interrupt())
panic("Fatal exception in interrupt");
if (panic_on_oops)
panic("Fatal exception");
do_exit(err);
}
void _exception(long signr, struct pt_regs *regs, int code,
unsigned long addr)
{
siginfo_t info;
if (!user_mode(regs))
die("Unhandled exception in kernel mode", regs, signr);
memset(&info, 0, sizeof(info));
info.si_signo = signr;
info.si_code = code;
info.si_addr = (void __user *)addr;
force_sig_info(signr, &info, current);
/*
* Init gets no signals that it doesn't have a handler for.
* That's all very well, but if it has caused a synchronous
* exception and we ignore the resulting signal, it will just
* generate the same exception over and over again and we get
* nowhere. Better to kill it and let the kernel panic.
*/
if (is_init(current)) {
__sighandler_t handler;
spin_lock_irq(¤t->sighand->siglock);
handler = current->sighand->action[signr-1].sa.sa_handler;
spin_unlock_irq(¤t->sighand->siglock);
if (handler == SIG_DFL) {
/* init has generated a synchronous exception
and it doesn't have a handler for the signal */
printk(KERN_CRIT "init has generated signal %ld "
"but has no handler for it\n", signr);
do_exit(signr);
}
}
}
asmlinkage void do_nmi(unsigned long ecr, struct pt_regs *regs)
{
printk(KERN_ALERT "Got Non-Maskable Interrupt, dumping regs\n");
show_regs_log_lvl(regs, KERN_ALERT);
show_stack_log_lvl(current, regs->sp, regs, KERN_ALERT);
}
asmlinkage void do_critical_exception(unsigned long ecr, struct pt_regs *regs)
{
die("Critical exception", regs, SIGKILL);
}
asmlinkage void do_address_exception(unsigned long ecr, struct pt_regs *regs)
{
_exception(SIGBUS, regs, BUS_ADRALN, regs->pc);
}
/* This way of handling undefined instructions is stolen from ARM */
static LIST_HEAD(undef_hook);
static spinlock_t undef_lock = SPIN_LOCK_UNLOCKED;
void register_undef_hook(struct undef_hook *hook)
{
spin_lock_irq(&undef_lock);
list_add(&hook->node, &undef_hook);
spin_unlock_irq(&undef_lock);
}
void unregister_undef_hook(struct undef_hook *hook)
{
spin_lock_irq(&undef_lock);
list_del(&hook->node);
spin_unlock_irq(&undef_lock);
}
static int do_cop_absent(u32 insn)
{
int cop_nr;
u32 cpucr;
if ((insn & 0xfdf00000) == 0xf1900000)
/* LDC0 */
cop_nr = 0;
else
cop_nr = (insn >> 13) & 0x7;
/* Try enabling the coprocessor */
cpucr = sysreg_read(CPUCR);
cpucr |= (1 << (24 + cop_nr));
sysreg_write(CPUCR, cpucr);
cpucr = sysreg_read(CPUCR);
if (!(cpucr & (1 << (24 + cop_nr))))
return -ENODEV;
return 0;
}
int is_valid_bugaddr(unsigned long pc)
{
unsigned short opcode;
if (pc < PAGE_OFFSET)
return 0;
if (probe_kernel_address((u16 *)pc, opcode))
return 0;
return opcode == AVR32_BUG_OPCODE;
}
asmlinkage void do_illegal_opcode(unsigned long ecr, struct pt_regs *regs)
{
u32 insn;
struct undef_hook *hook;
void __user *pc;
long code;
if (!user_mode(regs) && (ecr == ECR_ILLEGAL_OPCODE)) {
enum bug_trap_type type;
type = report_bug(regs->pc);
switch (type) {
case BUG_TRAP_TYPE_NONE:
break;
case BUG_TRAP_TYPE_WARN:
regs->pc += 2;
return;
case BUG_TRAP_TYPE_BUG:
die("Kernel BUG", regs, SIGKILL);
}
}
local_irq_enable();
if (user_mode(regs)) {
pc = (void __user *)instruction_pointer(regs);
if (get_user(insn, (u32 __user *)pc))
goto invalid_area;
if (ecr == ECR_COPROC_ABSENT && !do_cop_absent(insn))
return;
spin_lock_irq(&undef_lock);
list_for_each_entry(hook, &undef_hook, node) {
if ((insn & hook->insn_mask) == hook->insn_val) {
if (hook->fn(regs, insn) == 0) {
spin_unlock_irq(&undef_lock);
return;
}
}
}
spin_unlock_irq(&undef_lock);
}
switch (ecr) {
case ECR_PRIVILEGE_VIOLATION:
code = ILL_PRVOPC;
break;
case ECR_COPROC_ABSENT:
code = ILL_COPROC;
break;
default:
code = ILL_ILLOPC;
break;
}
_exception(SIGILL, regs, code, regs->pc);
return;
invalid_area:
_exception(SIGSEGV, regs, SEGV_MAPERR, regs->pc);
}
asmlinkage void do_fpe(unsigned long ecr, struct pt_regs *regs)
{
/* We have no FPU yet */
_exception(SIGILL, regs, ILL_COPROC, regs->pc);
}
void __init trap_init(void)
{
}
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