mirror_ubuntu-kernels/arch/arm/kernel/irq.c

157 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/kernel/irq.c
*
* Copyright (C) 1992 Linus Torvalds
* Modifications for ARM processor Copyright (C) 1995-2000 Russell King.
*
* Support for Dynamic Tick Timer Copyright (C) 2004-2005 Nokia Corporation.
* Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and
* Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.
*
* This file contains the code used by various IRQ handling routines:
* asking for different IRQ's should be done through these routines
* instead of just grabbing them. Thus setups with different IRQ numbers
* shouldn't result in any weird surprises, and installing new handlers
* should be easier.
*
* IRQ's are in fact implemented a bit like signal handlers for the kernel.
* Naturally it's not a 1:1 relation, but there are similarities.
*/
#include <linux/signal.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/random.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/seq_file.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/kallsyms.h>
#include <linux/proc_fs.h>
#include <linux/export.h>
#include <asm/hardware/cache-l2x0.h>
#include <asm/hardware/cache-uniphier.h>
#include <asm/outercache.h>
#include <asm/softirq_stack.h>
#include <asm/exception.h>
#include <asm/mach/arch.h>
#include <asm/mach/irq.h>
#include <asm/mach/time.h>
#include "reboot.h"
unsigned long irq_err_count;
#ifdef CONFIG_IRQSTACKS
asmlinkage DEFINE_PER_CPU_READ_MOSTLY(u8 *, irq_stack_ptr);
static void __init init_irq_stacks(void)
{
u8 *stack;
int cpu;
for_each_possible_cpu(cpu) {
if (!IS_ENABLED(CONFIG_VMAP_STACK))
stack = (u8 *)__get_free_pages(GFP_KERNEL,
THREAD_SIZE_ORDER);
else
stack = __vmalloc_node(THREAD_SIZE, THREAD_ALIGN,
THREADINFO_GFP, NUMA_NO_NODE,
__builtin_return_address(0));
if (WARN_ON(!stack))
break;
per_cpu(irq_stack_ptr, cpu) = &stack[THREAD_SIZE];
}
}
#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK
static void ____do_softirq(void *arg)
{
__do_softirq();
}
void do_softirq_own_stack(void)
{
call_with_stack(____do_softirq, NULL,
__this_cpu_read(irq_stack_ptr));
}
#endif
#endif
int arch_show_interrupts(struct seq_file *p, int prec)
{
#ifdef CONFIG_FIQ
show_fiq_list(p, prec);
#endif
#ifdef CONFIG_SMP
show_ipi_list(p, prec);
#endif
seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
return 0;
}
/*
* handle_IRQ handles all hardware IRQ's. Decoded IRQs should
* not come via this function. Instead, they should provide their
* own 'handler'. Used by platform code implementing C-based 1st
* level decoding.
*/
void handle_IRQ(unsigned int irq, struct pt_regs *regs)
{
struct irq_desc *desc;
/*
* Some hardware gives randomly wrong interrupts. Rather
* than crashing, do something sensible.
*/
if (unlikely(!irq || irq >= nr_irqs))
desc = NULL;
else
desc = irq_to_desc(irq);
if (likely(desc))
handle_irq_desc(desc);
else
ack_bad_irq(irq);
}
void __init init_IRQ(void)
{
int ret;
#ifdef CONFIG_IRQSTACKS
init_irq_stacks();
#endif
if (IS_ENABLED(CONFIG_OF) && !machine_desc->init_irq)
irqchip_init();
else
machine_desc->init_irq();
if (IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_CACHE_L2X0) &&
(machine_desc->l2c_aux_mask || machine_desc->l2c_aux_val)) {
if (!outer_cache.write_sec)
outer_cache.write_sec = machine_desc->l2c_write_sec;
ret = l2x0_of_init(machine_desc->l2c_aux_val,
machine_desc->l2c_aux_mask);
if (ret && ret != -ENODEV)
pr_err("L2C: failed to init: %d\n", ret);
}
uniphier_cache_init();
}
#ifdef CONFIG_SPARSE_IRQ
int __init arch_probe_nr_irqs(void)
{
nr_irqs = machine_desc->nr_irqs ? machine_desc->nr_irqs : NR_IRQS;
return nr_irqs;
}
#endif