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linux/arch/mips/kernel/irq.c
Paul Gortmaker 848484e2c4 mips: remove needless include of module.h from core kernel files.
None of these files are using modular infrastructure, and build
tests reveal that none of these files are really relying on any
implicit inclusions via. module.h either.  So delete them.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:57 -04:00

166 lines
3.3 KiB
C

/*
* 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/system.h>
#include <asm/uaccess.h>
#ifdef CONFIG_KGDB
int kgdb_early_setup;
#endif
static unsigned long irq_map[NR_IRQS / BITS_PER_LONG];
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_clear_bit();
clear_bit(irq, irq_map);
smp_mb__after_clear_bit();
}
/*
* '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)
{
smtc_im_ack_irq(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 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();
if (!smtc_handle_on_other_cpu(irq))
generic_handle_irq(irq);
irq_exit();
}
#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
/*
* To avoid inefficient and in some cases pathological re-checking of
* IRQ affinity, we have this variant that skips the affinity check.
*/
void __irq_entry do_IRQ_no_affinity(unsigned int irq)
{
irq_enter();
smtc_im_backstop(irq);
generic_handle_irq(irq);
irq_exit();
}
#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */