diff options
Diffstat (limited to 'kernel/arch/mips/kernel/irq.c')
| -rw-r--r-- | kernel/arch/mips/kernel/irq.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/kernel/arch/mips/kernel/irq.c b/kernel/arch/mips/kernel/irq.c new file mode 100644 index 000000000..3c8a18a00 --- /dev/null +++ b/kernel/arch/mips/kernel/irq.c @@ -0,0 +1,147 @@ +/* + * 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 <asm/uaccess.h> + +#ifdef CONFIG_KGDB +int kgdb_early_setup; +#endif + +static DECLARE_BITMAP(irq_map, NR_IRQS); + +int allocate_irqno(void) +{ + int irq; + +again: + irq = find_first_zero_bit(irq_map, NR_IRQS); + + if (irq >= NR_IRQS) + return -ENOSPC; + + if (test_and_set_bit(irq, irq_map)) + goto again; + + return irq; +} + +/* + * Allocate the 16 legacy interrupts for i8259 devices. This happens early + * in the kernel initialization so treating allocation failure as BUG() is + * ok. + */ +void __init alloc_legacy_irqno(void) +{ + int i; + + for (i = 0; i <= 16; i++) + BUG_ON(test_and_set_bit(i, irq_map)); +} + +void free_irqno(unsigned int irq) +{ + smp_mb__before_atomic(); + clear_bit(irq, irq_map); + smp_mb__after_atomic(); +} + +/* + * '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; + +#ifdef CONFIG_KGDB + if (kgdb_early_setup) + return; +#endif + + for (i = 0; i < NR_IRQS; i++) + irq_set_noprobe(i); + + arch_init_irq(); + +#ifdef CONFIG_KGDB + if (!kgdb_early_setup) + kgdb_early_setup = 1; +#endif +} + +#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(); +} + |