Loading...
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
25#include <linux/atomic.h>
26#include <linux/uaccess.h>
27
28void *irq_stack[NR_CPUS];
29
30/*
31 * 'what should we do if we get a hw irq event on an illegal vector'.
32 * each architecture has to answer this themselves.
33 */
34void ack_bad_irq(unsigned int irq)
35{
36 printk("unexpected IRQ # %d\n", irq);
37}
38
39atomic_t irq_err_count;
40
41int arch_show_interrupts(struct seq_file *p, int prec)
42{
43 seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
44 return 0;
45}
46
47asmlinkage void spurious_interrupt(void)
48{
49 atomic_inc(&irq_err_count);
50}
51
52void __init init_IRQ(void)
53{
54 int i;
55
56 for (i = 0; i < NR_IRQS; i++)
57 irq_set_noprobe(i);
58
59 if (cpu_has_veic)
60 clear_c0_status(ST0_IM);
61
62 arch_init_irq();
63
64 for_each_possible_cpu(i) {
65 int irq_pages = IRQ_STACK_SIZE / PAGE_SIZE;
66 void *s = (void *)__get_free_pages(GFP_KERNEL, irq_pages);
67
68 irq_stack[i] = s;
69 pr_debug("CPU%d IRQ stack at 0x%p - 0x%p\n", i,
70 irq_stack[i], irq_stack[i] + IRQ_STACK_SIZE);
71 }
72}
73
74#ifdef CONFIG_DEBUG_STACKOVERFLOW
75static inline void check_stack_overflow(void)
76{
77 unsigned long sp;
78
79 __asm__ __volatile__("move %0, $sp" : "=r" (sp));
80 sp &= THREAD_MASK;
81
82 /*
83 * Check for stack overflow: is there less than STACK_WARN free?
84 * STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
85 */
86 if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
87 printk("do_IRQ: stack overflow: %ld\n",
88 sp - sizeof(struct thread_info));
89 dump_stack();
90 }
91}
92#else
93static inline void check_stack_overflow(void) {}
94#endif
95
96
97/*
98 * do_IRQ handles all normal device IRQ's (the special
99 * SMP cross-CPU interrupts have their own specific
100 * handlers).
101 */
102void __irq_entry do_IRQ(unsigned int irq)
103{
104 irq_enter();
105 check_stack_overflow();
106 generic_handle_irq(irq);
107 irq_exit();
108}
109
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
25#include <linux/atomic.h>
26#include <asm/uaccess.h>
27
28#ifdef CONFIG_KGDB
29int kgdb_early_setup;
30#endif
31
32static unsigned long irq_map[NR_IRQS / BITS_PER_LONG];
33
34int allocate_irqno(void)
35{
36 int irq;
37
38again:
39 irq = find_first_zero_bit(irq_map, NR_IRQS);
40
41 if (irq >= NR_IRQS)
42 return -ENOSPC;
43
44 if (test_and_set_bit(irq, irq_map))
45 goto again;
46
47 return irq;
48}
49
50/*
51 * Allocate the 16 legacy interrupts for i8259 devices. This happens early
52 * in the kernel initialization so treating allocation failure as BUG() is
53 * ok.
54 */
55void __init alloc_legacy_irqno(void)
56{
57 int i;
58
59 for (i = 0; i <= 16; i++)
60 BUG_ON(test_and_set_bit(i, irq_map));
61}
62
63void free_irqno(unsigned int irq)
64{
65 smp_mb__before_clear_bit();
66 clear_bit(irq, irq_map);
67 smp_mb__after_clear_bit();
68}
69
70/*
71 * 'what should we do if we get a hw irq event on an illegal vector'.
72 * each architecture has to answer this themselves.
73 */
74void ack_bad_irq(unsigned int irq)
75{
76 smtc_im_ack_irq(irq);
77 printk("unexpected IRQ # %d\n", irq);
78}
79
80atomic_t irq_err_count;
81
82int arch_show_interrupts(struct seq_file *p, int prec)
83{
84 seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
85 return 0;
86}
87
88asmlinkage void spurious_interrupt(void)
89{
90 atomic_inc(&irq_err_count);
91}
92
93void __init init_IRQ(void)
94{
95 int i;
96
97#ifdef CONFIG_KGDB
98 if (kgdb_early_setup)
99 return;
100#endif
101
102 for (i = 0; i < NR_IRQS; i++)
103 irq_set_noprobe(i);
104
105 arch_init_irq();
106
107#ifdef CONFIG_KGDB
108 if (!kgdb_early_setup)
109 kgdb_early_setup = 1;
110#endif
111}
112
113#ifdef DEBUG_STACKOVERFLOW
114static inline void check_stack_overflow(void)
115{
116 unsigned long sp;
117
118 __asm__ __volatile__("move %0, $sp" : "=r" (sp));
119 sp &= THREAD_MASK;
120
121 /*
122 * Check for stack overflow: is there less than STACK_WARN free?
123 * STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
124 */
125 if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
126 printk("do_IRQ: stack overflow: %ld\n",
127 sp - sizeof(struct thread_info));
128 dump_stack();
129 }
130}
131#else
132static inline void check_stack_overflow(void) {}
133#endif
134
135
136/*
137 * do_IRQ handles all normal device IRQ's (the special
138 * SMP cross-CPU interrupts have their own specific
139 * handlers).
140 */
141void __irq_entry do_IRQ(unsigned int irq)
142{
143 irq_enter();
144 check_stack_overflow();
145 if (!smtc_handle_on_other_cpu(irq))
146 generic_handle_irq(irq);
147 irq_exit();
148}
149
150#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
151/*
152 * To avoid inefficient and in some cases pathological re-checking of
153 * IRQ affinity, we have this variant that skips the affinity check.
154 */
155
156void __irq_entry do_IRQ_no_affinity(unsigned int irq)
157{
158 irq_enter();
159 smtc_im_backstop(irq);
160 generic_handle_irq(irq);
161 irq_exit();
162}
163
164#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */