Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * 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 = ocd_read(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);

        add_taint(TAINT_DIE);

        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_global_init(current)) {

                __sighandler_t handler;

                spin_lock_irq(&current->sighand->siglock);

                handler = current->sighand->action[signr-1].sa.sa_handler;

                spin_unlock_irq(&current->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 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;

}

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, 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);

                }

        }

        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)

{

}