android_kernel_xiaomi_sm8350/arch/mips/kernel/irq.c
Ralf Baechle 1146fe3050 [MIPS] SMTC: Make ack_bad_irq() safe with no IM backstop.
Issue reported and original patch by Kevin Kissel, cleaner (imho)
implementation by me.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-09-24 18:13:02 +01:00

158 lines
3.1 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/module.h>
#include <linux/proc_fs.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/random.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/kallsyms.h>
#include <asm/atomic.h>
#include <asm/system.h>
#include <asm/uaccess.h>
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;
}
EXPORT_SYMBOL_GPL(allocate_irqno);
/*
* 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();
}
EXPORT_SYMBOL_GPL(free_irqno);
/*
* '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;
/*
* Generic, controller-independent functions:
*/
int show_interrupts(struct seq_file *p, void *v)
{
int i = *(loff_t *) v, j;
struct irqaction * action;
unsigned long flags;
if (i == 0) {
seq_printf(p, " ");
for_each_online_cpu(j)
seq_printf(p, "CPU%d ",j);
seq_putc(p, '\n');
}
if (i < NR_IRQS) {
spin_lock_irqsave(&irq_desc[i].lock, flags);
action = irq_desc[i].action;
if (!action)
goto skip;
seq_printf(p, "%3d: ",i);
#ifndef CONFIG_SMP
seq_printf(p, "%10u ", kstat_irqs(i));
#else
for_each_online_cpu(j)
seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
#endif
seq_printf(p, " %14s", irq_desc[i].chip->name);
seq_printf(p, " %s", action->name);
for (action=action->next; action; action = action->next)
seq_printf(p, ", %s", action->name);
seq_putc(p, '\n');
skip:
spin_unlock_irqrestore(&irq_desc[i].lock, flags);
} else if (i == NR_IRQS) {
seq_putc(p, '\n');
seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
}
return 0;
}
asmlinkage void spurious_interrupt(void)
{
atomic_inc(&irq_err_count);
}
#ifdef CONFIG_KGDB
extern void breakpoint(void);
extern void set_debug_traps(void);
static int kgdb_flag = 1;
static int __init nokgdb(char *str)
{
kgdb_flag = 0;
return 1;
}
__setup("nokgdb", nokgdb);
#endif
void __init init_IRQ(void)
{
arch_init_irq();
#ifdef CONFIG_KGDB
if (kgdb_flag) {
printk("Wait for gdb client connection ...\n");
set_debug_traps();
breakpoint();
}
#endif
}