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 33 unsigned long irq_err_count; 34 35 DEFINE_PER_CPU(unsigned long *, irq_stack_ptr); 36 37 int arch_show_interrupts(struct seq_file *p, int prec) 38 { 39 show_ipi_list(p, prec); 40 seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count); 41 return 0; 42 } 43 44 void (*handle_arch_irq)(struct pt_regs *) = NULL; 45 46 void __init set_handle_irq(void (*handle_irq)(struct pt_regs *)) 47 { 48 if (handle_arch_irq) 49 return; 50 51 handle_arch_irq = handle_irq; 52 } 53 54 #ifdef CONFIG_VMAP_STACK 55 static void init_irq_stacks(void) 56 { 57 int cpu; 58 unsigned long *p; 59 60 for_each_possible_cpu(cpu) { 61 /* 62 * To ensure that VMAP'd stack overflow detection works 63 * correctly, the IRQ stacks need to have the same 64 * alignment as other stacks. 65 */ 66 p = __vmalloc_node_range(IRQ_STACK_SIZE, THREAD_ALIGN, 67 VMALLOC_START, VMALLOC_END, 68 THREADINFO_GFP, PAGE_KERNEL, 69 0, cpu_to_node(cpu), 70 __builtin_return_address(0)); 71 72 per_cpu(irq_stack_ptr, cpu) = p; 73 } 74 } 75 #else 76 /* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */ 77 DEFINE_PER_CPU_ALIGNED(unsigned long [IRQ_STACK_SIZE/sizeof(long)], irq_stack); 78 79 static void init_irq_stacks(void) 80 { 81 int cpu; 82 83 for_each_possible_cpu(cpu) 84 per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu); 85 } 86 #endif 87 88 void __init init_IRQ(void) 89 { 90 init_irq_stacks(); 91 irqchip_init(); 92 if (!handle_arch_irq) 93 panic("No interrupt controller found."); 94 } 95