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v3.5.6
  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 */
v3.1
  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/module.h>
 17#include <linux/proc_fs.h>
 18#include <linux/mm.h>
 19#include <linux/random.h>
 20#include <linux/sched.h>
 21#include <linux/seq_file.h>
 22#include <linux/kallsyms.h>
 23#include <linux/kgdb.h>
 24#include <linux/ftrace.h>
 25
 26#include <linux/atomic.h>
 27#include <asm/system.h>
 28#include <asm/uaccess.h>
 29
 30#ifdef CONFIG_KGDB
 31int kgdb_early_setup;
 32#endif
 33
 34static unsigned long irq_map[NR_IRQS / BITS_PER_LONG];
 35
 36int allocate_irqno(void)
 37{
 38	int irq;
 39
 40again:
 41	irq = find_first_zero_bit(irq_map, NR_IRQS);
 42
 43	if (irq >= NR_IRQS)
 44		return -ENOSPC;
 45
 46	if (test_and_set_bit(irq, irq_map))
 47		goto again;
 48
 49	return irq;
 50}
 51
 52/*
 53 * Allocate the 16 legacy interrupts for i8259 devices.  This happens early
 54 * in the kernel initialization so treating allocation failure as BUG() is
 55 * ok.
 56 */
 57void __init alloc_legacy_irqno(void)
 58{
 59	int i;
 60
 61	for (i = 0; i <= 16; i++)
 62		BUG_ON(test_and_set_bit(i, irq_map));
 63}
 64
 65void free_irqno(unsigned int irq)
 66{
 67	smp_mb__before_clear_bit();
 68	clear_bit(irq, irq_map);
 69	smp_mb__after_clear_bit();
 70}
 71
 72/*
 73 * 'what should we do if we get a hw irq event on an illegal vector'.
 74 * each architecture has to answer this themselves.
 75 */
 76void ack_bad_irq(unsigned int irq)
 77{
 78	smtc_im_ack_irq(irq);
 79	printk("unexpected IRQ # %d\n", irq);
 80}
 81
 82atomic_t irq_err_count;
 83
 84int arch_show_interrupts(struct seq_file *p, int prec)
 85{
 86	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
 87	return 0;
 88}
 89
 90asmlinkage void spurious_interrupt(void)
 91{
 92	atomic_inc(&irq_err_count);
 93}
 94
 95void __init init_IRQ(void)
 96{
 97	int i;
 98
 99#ifdef CONFIG_KGDB
100	if (kgdb_early_setup)
101		return;
102#endif
103
104	for (i = 0; i < NR_IRQS; i++)
105		irq_set_noprobe(i);
106
107	arch_init_irq();
108
109#ifdef CONFIG_KGDB
110	if (!kgdb_early_setup)
111		kgdb_early_setup = 1;
112#endif
113}
114
115#ifdef DEBUG_STACKOVERFLOW
116static inline void check_stack_overflow(void)
117{
118	unsigned long sp;
119
120	__asm__ __volatile__("move %0, $sp" : "=r" (sp));
121	sp &= THREAD_MASK;
122
123	/*
124	 * Check for stack overflow: is there less than STACK_WARN free?
125	 * STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
126	 */
127	if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
128		printk("do_IRQ: stack overflow: %ld\n",
129		       sp - sizeof(struct thread_info));
130		dump_stack();
131	}
132}
133#else
134static inline void check_stack_overflow(void) {}
135#endif
136
137
138/*
139 * do_IRQ handles all normal device IRQ's (the special
140 * SMP cross-CPU interrupts have their own specific
141 * handlers).
142 */
143void __irq_entry do_IRQ(unsigned int irq)
144{
145	irq_enter();
146	check_stack_overflow();
147	if (!smtc_handle_on_other_cpu(irq))
148		generic_handle_irq(irq);
149	irq_exit();
150}
151
152#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
153/*
154 * To avoid inefficient and in some cases pathological re-checking of
155 * IRQ affinity, we have this variant that skips the affinity check.
156 */
157
158void __irq_entry do_IRQ_no_affinity(unsigned int irq)
159{
160	irq_enter();
161	smtc_im_backstop(irq);
162	generic_handle_irq(irq);
163	irq_exit();
164}
165
166#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */