1 /* 2 * linux/arch/arm/kernel/irq.c 3 * 4 * Copyright (C) 1992 Linus Torvalds 5 * Modifications for ARM processor Copyright (C) 1995-2000 Russell King. 6 * 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 * 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 file contains the code used by various IRQ handling routines: 16 * asking for different IRQ's should be done through these routines 17 * instead of just grabbing them. Thus setups with different IRQ numbers 18 * shouldn't result in any weird surprises, and installing new handlers 19 * should be easier. 20 * 21 * IRQ's are in fact implemented a bit like signal handlers for the kernel. 22 * Naturally it's not a 1:1 relation, but there are similarities. 23 */ 24 #include <linux/kernel_stat.h> 25 #include <linux/signal.h> 26 #include <linux/ioport.h> 27 #include <linux/interrupt.h> 28 #include <linux/irq.h> 29 #include <linux/irqchip.h> 30 #include <linux/random.h> 31 #include <linux/smp.h> 32 #include <linux/init.h> 33 #include <linux/seq_file.h> 34 #include <linux/errno.h> 35 #include <linux/list.h> 36 #include <linux/kallsyms.h> 37 #include <linux/proc_fs.h> 38 #include <linux/export.h> 39 40 #include <asm/hardware/cache-l2x0.h> 41 #include <asm/hardware/cache-uniphier.h> 42 #include <asm/outercache.h> 43 #include <asm/exception.h> 44 #include <asm/mach/arch.h> 45 #include <asm/mach/irq.h> 46 #include <asm/mach/time.h> 47 48 unsigned long irq_err_count; 49 50 int arch_show_interrupts(struct seq_file *p, int prec) 51 { 52 #ifdef CONFIG_FIQ 53 show_fiq_list(p, prec); 54 #endif 55 #ifdef CONFIG_SMP 56 show_ipi_list(p, prec); 57 #endif 58 seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count); 59 return 0; 60 } 61 62 /* 63 * handle_IRQ handles all hardware IRQ's. Decoded IRQs should 64 * not come via this function. Instead, they should provide their 65 * own 'handler'. Used by platform code implementing C-based 1st 66 * level decoding. 67 */ 68 void handle_IRQ(unsigned int irq, struct pt_regs *regs) 69 { 70 __handle_domain_irq(NULL, irq, false, regs); 71 } 72 73 /* 74 * asm_do_IRQ is the interface to be used from assembly code. 75 */ 76 asmlinkage void __exception_irq_entry 77 asm_do_IRQ(unsigned int irq, struct pt_regs *regs) 78 { 79 handle_IRQ(irq, regs); 80 } 81 82 void __init init_IRQ(void) 83 { 84 int ret; 85 86 if (IS_ENABLED(CONFIG_OF) && !machine_desc->init_irq) 87 irqchip_init(); 88 else 89 machine_desc->init_irq(); 90 91 if (IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_CACHE_L2X0) && 92 (machine_desc->l2c_aux_mask || machine_desc->l2c_aux_val)) { 93 if (!outer_cache.write_sec) 94 outer_cache.write_sec = machine_desc->l2c_write_sec; 95 ret = l2x0_of_init(machine_desc->l2c_aux_val, 96 machine_desc->l2c_aux_mask); 97 if (ret && ret != -ENODEV) 98 pr_err("L2C: failed to init: %d\n", ret); 99 } 100 101 uniphier_cache_init(); 102 } 103 104 #ifdef CONFIG_SPARSE_IRQ 105 int __init arch_probe_nr_irqs(void) 106 { 107 nr_irqs = machine_desc->nr_irqs ? machine_desc->nr_irqs : NR_IRQS; 108 return nr_irqs; 109 } 110 #endif 111