/* * 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. * * Code to handle x86 style IRQs plus some generic interrupt stuff. * * Copyright (C) 1992 Linus Torvalds * Copyright (C) 1994 - 2000 Ralf Baechle */ #include <linux/kernel.h> #include <linux/delay.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/kernel_stat.h> #include <linux/proc_fs.h> #include <linux/mm.h> #include <linux/random.h> #include <linux/sched.h> #include <linux/seq_file.h> #include <linux/kallsyms.h> #include <linux/kgdb.h> #include <linux/ftrace.h> #include <linux/atomic.h> #include <linux/uaccess.h> void *irq_stack[NR_CPUS]; /* * 'what should we do if we get a hw irq event on an illegal vector'. * each architecture has to answer this themselves. */ void ack_bad_irq(unsigned int irq) { printk("unexpected IRQ # %d\n", irq); } atomic_t irq_err_count; int arch_show_interrupts(struct seq_file *p, int prec) { seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count)); return 0; } asmlinkage void spurious_interrupt(void) { atomic_inc(&irq_err_count); } void __init init_IRQ(void) { int i; for (i = 0; i < NR_IRQS; i++) irq_set_noprobe(i); if (cpu_has_veic) clear_c0_status(ST0_IM); arch_init_irq(); for_each_possible_cpu(i) { int irq_pages = IRQ_STACK_SIZE / PAGE_SIZE; void *s = (void *)__get_free_pages(GFP_KERNEL, irq_pages); irq_stack[i] = s; pr_debug("CPU%d IRQ stack at 0x%p - 0x%p\n", i, irq_stack[i], irq_stack[i] + IRQ_STACK_SIZE); } } #ifdef CONFIG_DEBUG_STACKOVERFLOW static inline void check_stack_overflow(void) { unsigned long sp; __asm__ __volatile__("move %0, $sp" : "=r" (sp)); sp &= THREAD_MASK; /* * Check for stack overflow: is there less than STACK_WARN free? * STACK_WARN is defined as 1/8 of THREAD_SIZE by default. */ if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) { printk("do_IRQ: stack overflow: %ld\n", sp - sizeof(struct thread_info)); dump_stack(); } } #else static inline void check_stack_overflow(void) {} #endif /* * do_IRQ handles all normal device IRQ's (the special * SMP cross-CPU interrupts have their own specific * handlers). */ void __irq_entry do_IRQ(unsigned int irq) { irq_enter(); check_stack_overflow(); generic_handle_irq(irq); irq_exit(); }