diff options
Diffstat (limited to 'arch/nios2/kernel/traps.c')
| -rw-r--r-- | arch/nios2/kernel/traps.c | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/arch/nios2/kernel/traps.c b/arch/nios2/kernel/traps.c new file mode 100644 index 00000000000..b7b97641a9a --- /dev/null +++ b/arch/nios2/kernel/traps.c @@ -0,0 +1,185 @@ +/* + * Hardware exception handling + * + * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> + * Copyright (C) 2004 Microtronix Datacom Ltd. + * Copyright (C) 2001 Vic Phillips + * + * 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/sched.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/ptrace.h> + +#include <asm/traps.h> +#include <asm/sections.h> +#include <asm/uaccess.h> + +static DEFINE_SPINLOCK(die_lock); + +void die(const char *str, struct pt_regs *regs, long err) +{ + console_verbose(); + spin_lock_irq(&die_lock); + pr_warn("Oops: %s, sig: %ld\n", str, err); + show_regs(regs); + 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); +} + +void _exception(int signo, struct pt_regs *regs, int code, unsigned long addr) +{ + siginfo_t info; + + if (!user_mode(regs)) + die("Exception in kernel mode", regs, signo); + + info.si_signo = signo; + info.si_errno = 0; + info.si_code = code; + info.si_addr = (void __user *) addr; + force_sig_info(signo, &info, current); +} + +/* + * The show_stack is an external API which we do not use ourselves. + */ + +int kstack_depth_to_print = 48; + +void show_stack(struct task_struct *task, unsigned long *stack) +{ + unsigned long *endstack, addr; + int i; + + if (!stack) { + if (task) + stack = (unsigned long *)task->thread.ksp; + else + stack = (unsigned long *)&stack; + } + + addr = (unsigned long) stack; + endstack = (unsigned long *) PAGE_ALIGN(addr); + + pr_emerg("Stack from %08lx:", (unsigned long)stack); + for (i = 0; i < kstack_depth_to_print; i++) { + if (stack + 1 > endstack) + break; + if (i % 8 == 0) + pr_emerg("\n "); + pr_emerg(" %08lx", *stack++); + } + + pr_emerg("\nCall Trace:"); + i = 0; + while (stack + 1 <= endstack) { + addr = *stack++; + /* + * If the address is either in the text segment of the + * kernel, or in the region which contains vmalloc'ed + * memory, it *may* be the address of a calling + * routine; if so, print it so that someone tracing + * down the cause of the crash will be able to figure + * out the call path that was taken. + */ + if (((addr >= (unsigned long) _stext) && + (addr <= (unsigned long) _etext))) { + if (i % 4 == 0) + pr_emerg("\n "); + pr_emerg(" [<%08lx>]", addr); + i++; + } + } + pr_emerg("\n"); +} + +void __init trap_init(void) +{ + /* Nothing to do here */ +} + +/* Breakpoint handler */ +asmlinkage void breakpoint_c(struct pt_regs *fp) +{ + /* + * The breakpoint entry code has moved the PC on by 4 bytes, so we must + * move it back. This could be done on the host but we do it here + * because monitor.S of JTAG gdbserver does it too. + */ + fp->ea -= 4; + _exception(SIGTRAP, fp, TRAP_BRKPT, fp->ea); +} + +#ifndef CONFIG_NIOS2_ALIGNMENT_TRAP +/* Alignment exception handler */ +asmlinkage void handle_unaligned_c(struct pt_regs *fp, int cause) +{ + unsigned long addr = RDCTL(CTL_BADADDR); + + cause >>= 2; + fp->ea -= 4; + + if (fixup_exception(fp)) + return; + + if (!user_mode(fp)) { + pr_alert("Unaligned access from kernel mode, this might be a hardware\n"); + pr_alert("problem, dump registers and restart the instruction\n"); + pr_alert(" BADADDR 0x%08lx\n", addr); + pr_alert(" cause %d\n", cause); + pr_alert(" op-code 0x%08lx\n", *(unsigned long *)(fp->ea)); + show_regs(fp); + return; + } + + _exception(SIGBUS, fp, BUS_ADRALN, addr); +} +#endif /* CONFIG_NIOS2_ALIGNMENT_TRAP */ + +/* Illegal instruction handler */ +asmlinkage void handle_illegal_c(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGILL, fp, ILL_ILLOPC, fp->ea); +} + +/* Supervisor instruction handler */ +asmlinkage void handle_supervisor_instr(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGILL, fp, ILL_PRVOPC, fp->ea); +} + +/* Division error handler */ +asmlinkage void handle_diverror_c(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGFPE, fp, FPE_INTDIV, fp->ea); +} + +/* Unhandled exception handler */ +asmlinkage void unhandled_exception(struct pt_regs *regs, int cause) +{ + unsigned long addr = RDCTL(CTL_BADADDR); + + cause /= 4; + + pr_emerg("Unhandled exception #%d in %s mode (badaddr=0x%08lx)\n", + cause, user_mode(regs) ? "user" : "kernel", addr); + + regs->ea -= 4; + show_regs(regs); + + pr_emerg("opcode: 0x%08lx\n", *(unsigned long *)(regs->ea)); +} |