diff options
Diffstat (limited to 'arch/avr32/kernel/traps.c')
| -rw-r--r-- | arch/avr32/kernel/traps.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/arch/avr32/kernel/traps.c b/arch/avr32/kernel/traps.c new file mode 100644 index 000000000..682b24786 --- /dev/null +++ b/arch/avr32/kernel/traps.c @@ -0,0 +1,261 @@ +/* + * 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/hardirq.h> +#include <linux/init.h> +#include <linux/kallsyms.h> +#include <linux/kdebug.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 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", + str, err, ++die_counter); + + printk(KERN_EMERG); + +#ifdef CONFIG_PREEMPT + printk(KERN_CONT "PREEMPT "); +#endif +#ifdef CONFIG_FRAME_POINTER + printk(KERN_CONT "FRAME_POINTER "); +#endif + if (current_cpu_data.features & AVR32_FEATURE_OCD) { + unsigned long did = ocd_read(DID); + printk(KERN_CONT "chip: 0x%03lx:0x%04lx rev %lu\n", + (did >> 1) & 0x7ff, + (did >> 12) & 0x7fff, + (did >> 28) & 0xf); + } else { + printk(KERN_CONT "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); + 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); +} + +void _exception(long signr, struct pt_regs *regs, int code, + unsigned long addr) +{ + siginfo_t info; + + if (!user_mode(regs)) { + const struct exception_table_entry *fixup; + + /* Are we prepared to handle this kernel fault? */ + fixup = search_exception_tables(regs->pc); + if (fixup) { + regs->pc = fixup->fixup; + return; + } + 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); +} + +asmlinkage void do_nmi(unsigned long ecr, struct pt_regs *regs) +{ + int ret; + + nmi_enter(); + + ret = notify_die(DIE_NMI, "NMI", regs, 0, ecr, SIGINT); + switch (ret) { + case NOTIFY_OK: + case NOTIFY_STOP: + break; + case NOTIFY_BAD: + die("Fatal Non-Maskable Interrupt", regs, SIGINT); + default: + printk(KERN_ALERT "Got NMI, but nobody cared. Disabling...\n"); + nmi_disable(); + break; + } + nmi_exit(); +} + +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 DEFINE_SPINLOCK(undef_lock); + +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; +} + +#ifdef CONFIG_BUG +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; +} +#endif + +asmlinkage void do_illegal_opcode(unsigned long ecr, struct pt_regs *regs) +{ + u32 insn; + struct undef_hook *hook; + void __user *pc; + long code; + +#ifdef CONFIG_BUG + if (!user_mode(regs) && (ecr == ECR_ILLEGAL_OPCODE)) { + enum bug_trap_type type; + + type = report_bug(regs->pc, regs); + 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); + } + } +#endif + + 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) +{ + +} |