arch/arm64/kernel/irq.c

   1 /*
   2  * Based on arch/arm/kernel/irq.c
   3  *
   4  * Copyright (C) 1992 Linus Torvalds
   5  * Modifications for ARM processor Copyright (C) 1995-2000 Russell King.
   6  * Support for Dynamic Tick Timer Copyright (C) 2004-2005 Nokia Corporation.
   7  * Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and
   8  * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.
   9  * Copyright (C) 2012 ARM Ltd.
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 #include <linux/kernel_stat.h>
  25 #include <linux/irq.h>
  26 #include <linux/memory.h>
  27 #include <linux/smp.h>
  28 #include <linux/init.h>
  29 #include <linux/irqchip.h>
  30 #include <linux/seq_file.h>
  31 #include <linux/vmalloc.h>
  32 #include <asm/vmap_stack.h>
  33
  34 unsigned long irq_err_count;
  35
  36 DEFINE_PER_CPU(unsigned long *, irq_stack_ptr);
  37
  38 int arch_show_interrupts(struct seq_file *p, int prec)
  39 {
  40         show_ipi_list(p, prec);
  41         seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
  42         return 0;
  43 }
  44
  45 void (*handle_arch_irq)(struct pt_regs *) = NULL;
  46
  47 void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
  48 {
  49         if (handle_arch_irq)
  50                 return;
  51
  52         handle_arch_irq = handle_irq;
  53 }
  54
  55 #ifdef CONFIG_VMAP_STACK
  56 static void init_irq_stacks(void)
  57 {
  58         int cpu;
  59         unsigned long *p;
  60
  61         for_each_possible_cpu(cpu) {
  62                 p = arch_alloc_vmap_stack(IRQ_STACK_SIZE, cpu_to_node(cpu));
  63                 per_cpu(irq_stack_ptr, cpu) = p;
  64         }
  65 }
  66 #else
  67 /* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */
  68 DEFINE_PER_CPU_ALIGNED(unsigned long [IRQ_STACK_SIZE/sizeof(long)], irq_stack);
  69
  70 static void init_irq_stacks(void)
  71 {
  72         int cpu;
  73
  74         for_each_possible_cpu(cpu)
  75                 per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu);
  76 }
  77 #endif
  78
  79 void __init init_IRQ(void)
  80 {
  81         init_irq_stacks();
  82         irqchip_init();
  83         if (!handle_arch_irq)
  84                 panic("No interrupt controller found.");
  85 }