linux-stable/arch/mips/kernel/irq.c
Paul Burton 640356a487 MIPS: Clear Status IPL field when using EIC
When using an external interrupt controller (EIC) the interrupt mask
bits in the cop0 Status register are reused for the Interrupt Priority
Level, and any interrupts with a priority lower than the field will be
ignored. Clear the field to 0 by default such that all interrupts are
serviced. Without doing so we default to arbitrarily ignoring all or
some subset of interrupts.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Matt Redfearn <matt.redfearn@imgtec.com>
Tested-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: Joe Perches <joe@perches.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13272/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-28 12:35:02 +02:00

98 lines
2.1 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/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>
/*
* '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;
for (i = 0; i < NR_IRQS; i++)
irq_set_noprobe(i);
if (cpu_has_veic)
clear_c0_status(ST0_IM);
arch_init_irq();
}
#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();
}