| 1 | |
| 2 | * This file is subject to the terms and conditions of the GNU General Public
|
| 3 | * License. See the file "COPYING" in the main directory of this archive
|
| 4 | * for more details.
|
| 5 | *
|
| 6 | * Code to handle x86 style IRQs plus some generic interrupt stuff.
|
| 7 | *
|
| 8 | * Copyright (C) 1992 Linus Torvalds
|
| 9 | * Copyright (C) 1994 - 2000 Ralf Baechle
|
| 10 |
|
| 11 | #include <linux/kernel.h>
|
| 12 | #include <linux/delay.h>
|
| 13 | #include <linux/init.h>
|
| 14 | #include <linux/interrupt.h>
|
| 15 | #include <linux/kernel_stat.h>
|
| 16 | #include <linux/proc_fs.h>
|
| 17 | #include <linux/mm.h>
|
| 18 | #include <linux/random.h>
|
| 19 | #include <linux/sched.h>
|
| 20 | #include <linux/seq_file.h>
|
| 21 | #include <linux/kallsyms.h>
|
| 22 | #include <linux/kgdb.h>
|
| 23 | #include <linux/ftrace.h>
|
| 24 | #include <linux/irqdomain.h>
|
| 25 |
|
| 26 | #include <linux/atomic.h>
|
| 27 | #include <linux/uaccess.h>
|
| 28 |
|
| 29 | void *irq_stack[NR_CPUS];
|
| 30 |
|
| 31 | |
| 32 | * 'what should we do if we get a hw irq event on an illegal vector'.
|
| 33 | * each architecture has to answer this themselves.
|
| 34 |
|
| 35 | void ack_bad_irq(unsigned int irq)
|
| 36 | {
|
| 37 | printk("unexpected IRQ # %d\n", irq);
|
| 38 | }
|
| 39 |
|
| 40 | atomic_t irq_err_count;
|
| 41 |
|
| 42 | int arch_show_interrupts(struct seq_file *p, int prec)
|
| 43 | {
|
| 44 | seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
|
| 45 | return 0;
|
| 46 | }
|
| 47 |
|
| 48 | asmlinkage void spurious_interrupt(void)
|
| 49 | {
|
| 50 | atomic_inc(&irq_err_count);
|
| 51 | }
|
| 52 |
|
| 53 | void __init init_IRQ(void)
|
| 54 | {
|
| 55 | int i;
|
| 56 | unsigned int order = get_order(IRQ_STACK_SIZE);
|
| 57 |
|
| 58 | for (i = 0; i < NR_IRQS; i++)
|
| 59 | irq_set_noprobe(i);
|
| 60 |
|
| 61 | if (cpu_has_veic)
|
| 62 | clear_c0_status(ST0_IM);
|
| 63 |
|
| 64 | arch_init_irq();
|
| 65 |
|
| 66 | for_each_possible_cpu(i) {
|
| 67 | void *s = (void *)__get_free_pages(GFP_KERNEL, order);
|
| 68 |
|
| 69 | irq_stack[i] = s;
|
| 70 | pr_debug("CPU%d IRQ stack at 0x%p - 0x%p\n", i,
|
| 71 | irq_stack[i], irq_stack[i] + IRQ_STACK_SIZE);
|
| 72 | }
|
| 73 | }
|
| 74 |
|
| 75 | #ifdef CONFIG_DEBUG_STACKOVERFLOW
|
| 76 | static inline void check_stack_overflow(void)
|
| 77 | {
|
| 78 | unsigned long sp;
|
| 79 |
|
| 80 | __asm__ __volatile__("move %0, $sp" : "=r" (sp));
|
| 81 | sp &= THREAD_MASK;
|
| 82 |
|
| 83 | |
| 84 | * Check for stack overflow: is there less than STACK_WARN free?
|
| 85 | * STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
|
| 86 |
|
| 87 | if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
|
| 88 | printk("do_IRQ: stack overflow: %ld\n",
|
| 89 | sp - sizeof(struct thread_info));
|
| 90 | dump_stack();
|
| 91 | }
|
| 92 | }
|
| 93 | #else
|
| 94 | static inline void check_stack_overflow(void) {}
|
| 95 | #endif
|
| 96 |
|
| 97 |
|
| 98 | |
| 99 | * do_IRQ handles all normal device IRQ's (the special
|
| 100 | * SMP cross-CPU interrupts have their own specific
|
| 101 | * handlers).
|
| 102 |
|
| 103 | asmlinkage void __irq_entry do_IRQ(unsigned int irq)
|
| 104 | {
|
| 105 | irq_enter();
|
| 106 | check_stack_overflow();
|
| 107 | generic_handle_irq(irq);
|
| 108 | irq_exit();
|
| 109 | }
|
| 110 |
|
| 111 | #ifdef CONFIG_IRQ_DOMAIN
|
| 112 | void __irq_entry do_domain_IRQ(struct irq_domain *domain, unsigned int hwirq)
|
| 113 | {
|
| 114 | irq_enter();
|
| 115 | check_stack_overflow();
|
| 116 | generic_handle_domain_irq(domain, hwirq);
|
| 117 | irq_exit();
|
| 118 | }
|
| 119 | #endif
|