arch/arm64/kernel/irq.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Based on arch/arm/kernel/irq.c
   4  *
   5  * Copyright (C) 1992 Linus Torvalds
   6  * Modifications for ARM processor Copyright (C) 1995-2000 Russell King.
   7  * Support for Dynamic Tick Timer Copyright (C) 2004-2005 Nokia Corporation.
   8  * Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and
   9  * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.
  10  * Copyright (C) 2012 ARM Ltd.
  11  */
  12
  13 #include <linux/kernel_stat.h>
  14 #include <linux/irq.h>
  15 #include <linux/memory.h>
  16 #include <linux/smp.h>
  17 #include <linux/init.h>
  18 #include <linux/irqchip.h>
  19 #include <linux/seq_file.h>
  20 #include <linux/vmalloc.h>
  21 #include <asm/vmap_stack.h>
  22
  23 unsigned long irq_err_count;
  24
  25 /* Only access this in an NMI enter/exit */
  26 DEFINE_PER_CPU(struct nmi_ctx, nmi_contexts);
  27
  28 DEFINE_PER_CPU(unsigned long *, irq_stack_ptr);
  29
  30 int arch_show_interrupts(struct seq_file *p, int prec)
  31 {
  32         show_ipi_list(p, prec);
  33         seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
  34         return 0;
  35 }
  36
  37 #ifdef CONFIG_VMAP_STACK
  38 static void init_irq_stacks(void)
  39 {
  40         int cpu;
  41         unsigned long *p;
  42
  43         for_each_possible_cpu(cpu) {
  44                 p = arch_alloc_vmap_stack(IRQ_STACK_SIZE, cpu_to_node(cpu));
  45                 per_cpu(irq_stack_ptr, cpu) = p;
  46         }
  47 }
  48 #else
  49 /* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */
  50 DEFINE_PER_CPU_ALIGNED(unsigned long [IRQ_STACK_SIZE/sizeof(long)], irq_stack);
  51
  52 static void init_irq_stacks(void)
  53 {
  54         int cpu;
  55
  56         for_each_possible_cpu(cpu)
  57                 per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu);
  58 }
  59 #endif
  60
  61 void __init init_IRQ(void)
  62 {
  63         init_irq_stacks();
  64         irqchip_init();
  65         if (!handle_arch_irq)
  66                 panic("No interrupt controller found.");
  67 }