Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | * |
Russell King | 8749af6 | 2005-06-25 19:39:45 +0100 | [diff] [blame] | 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 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | #include <linux/kernel_stat.h> |
| 25 | #include <linux/module.h> |
| 26 | #include <linux/signal.h> |
| 27 | #include <linux/ioport.h> |
| 28 | #include <linux/interrupt.h> |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 29 | #include <linux/irq.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <linux/slab.h> |
| 31 | #include <linux/random.h> |
| 32 | #include <linux/smp.h> |
| 33 | #include <linux/init.h> |
| 34 | #include <linux/seq_file.h> |
| 35 | #include <linux/errno.h> |
| 36 | #include <linux/list.h> |
| 37 | #include <linux/kallsyms.h> |
| 38 | #include <linux/proc_fs.h> |
| 39 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | #include <asm/system.h> |
Russell King | 8749af6 | 2005-06-25 19:39:45 +0100 | [diff] [blame] | 41 | #include <asm/mach/time.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | |
| 43 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | * No architecture-specific irq_finish function defined in arm/arch/irqs.h. |
| 45 | */ |
| 46 | #ifndef irq_finish |
| 47 | #define irq_finish(irq) do { } while (0) |
| 48 | #endif |
| 49 | |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 50 | void (*init_arch_irq)(void) __initdata = NULL; |
| 51 | unsigned long irq_err_count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | |
| 53 | int show_interrupts(struct seq_file *p, void *v) |
| 54 | { |
| 55 | int i = *(loff_t *) v, cpu; |
| 56 | struct irqaction * action; |
| 57 | unsigned long flags; |
| 58 | |
| 59 | if (i == 0) { |
| 60 | char cpuname[12]; |
| 61 | |
| 62 | seq_printf(p, " "); |
| 63 | for_each_present_cpu(cpu) { |
| 64 | sprintf(cpuname, "CPU%d", cpu); |
| 65 | seq_printf(p, " %10s", cpuname); |
| 66 | } |
| 67 | seq_putc(p, '\n'); |
| 68 | } |
| 69 | |
| 70 | if (i < NR_IRQS) { |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 71 | spin_lock_irqsave(&irq_desc[i].lock, flags); |
| 72 | action = irq_desc[i].action; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | if (!action) |
| 74 | goto unlock; |
| 75 | |
| 76 | seq_printf(p, "%3d: ", i); |
| 77 | for_each_present_cpu(cpu) |
| 78 | seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]); |
David Brownell | 38c677c | 2006-08-01 22:26:25 +0100 | [diff] [blame] | 79 | seq_printf(p, " %10s", irq_desc[i].chip->name ? : "-"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | seq_printf(p, " %s", action->name); |
| 81 | for (action = action->next; action; action = action->next) |
| 82 | seq_printf(p, ", %s", action->name); |
| 83 | |
| 84 | seq_putc(p, '\n'); |
| 85 | unlock: |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 86 | spin_unlock_irqrestore(&irq_desc[i].lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 87 | } else if (i == NR_IRQS) { |
| 88 | #ifdef CONFIG_ARCH_ACORN |
| 89 | show_fiq_list(p, v); |
| 90 | #endif |
| 91 | #ifdef CONFIG_SMP |
| 92 | show_ipi_list(p); |
Russell King | 37ee16a | 2005-11-08 19:08:05 +0000 | [diff] [blame] | 93 | show_local_irqs(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | #endif |
| 95 | seq_printf(p, "Err: %10lu\n", irq_err_count); |
| 96 | } |
| 97 | return 0; |
| 98 | } |
| 99 | |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 100 | /* Handle bad interrupts */ |
| 101 | static struct irq_desc bad_irq_desc = { |
| 102 | .handle_irq = handle_bad_irq, |
| 103 | .lock = SPIN_LOCK_UNLOCKED |
| 104 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | |
| 106 | /* |
| 107 | * do_IRQ handles all hardware IRQ's. Decoded IRQs should not |
| 108 | * come via this function. Instead, they should provide their |
| 109 | * own 'handler' |
| 110 | */ |
Russell King | 7ab3f8d | 2007-03-02 15:01:36 +0000 | [diff] [blame] | 111 | asmlinkage void __exception asm_do_IRQ(unsigned int irq, struct pt_regs *regs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | { |
Linus Torvalds | e630015 | 2006-10-06 13:11:15 -0700 | [diff] [blame] | 113 | struct pt_regs *old_regs = set_irq_regs(regs); |
Russell King | 10dd5ce | 2006-11-23 11:41:32 +0000 | [diff] [blame] | 114 | struct irq_desc *desc = irq_desc + irq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | |
| 116 | /* |
| 117 | * Some hardware gives randomly wrong interrupts. Rather |
| 118 | * than crashing, do something sensible. |
| 119 | */ |
| 120 | if (irq >= NR_IRQS) |
| 121 | desc = &bad_irq_desc; |
| 122 | |
| 123 | irq_enter(); |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 124 | |
Linus Torvalds | 0cd61b6 | 2006-10-06 10:53:39 -0700 | [diff] [blame] | 125 | desc_handle_irq(irq, desc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 127 | /* AT91 specific workaround */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | irq_finish(irq); |
| 129 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | irq_exit(); |
Linus Torvalds | e630015 | 2006-10-06 13:11:15 -0700 | [diff] [blame] | 131 | set_irq_regs(old_regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | } |
| 133 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | void set_irq_flags(unsigned int irq, unsigned int iflags) |
| 135 | { |
Russell King | 10dd5ce | 2006-11-23 11:41:32 +0000 | [diff] [blame] | 136 | struct irq_desc *desc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | unsigned long flags; |
| 138 | |
| 139 | if (irq >= NR_IRQS) { |
| 140 | printk(KERN_ERR "Trying to set irq flags for IRQ%d\n", irq); |
| 141 | return; |
| 142 | } |
| 143 | |
| 144 | desc = irq_desc + irq; |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 145 | spin_lock_irqsave(&desc->lock, flags); |
| 146 | desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; |
| 147 | if (iflags & IRQF_VALID) |
| 148 | desc->status &= ~IRQ_NOREQUEST; |
| 149 | if (iflags & IRQF_PROBE) |
| 150 | desc->status &= ~IRQ_NOPROBE; |
| 151 | if (!(iflags & IRQF_NOAUTOEN)) |
| 152 | desc->status &= ~IRQ_NOAUTOEN; |
| 153 | spin_unlock_irqrestore(&desc->lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | } |
| 155 | |
| 156 | void __init init_IRQ(void) |
| 157 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | int irq; |
| 159 | |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 160 | for (irq = 0; irq < NR_IRQS; irq++) |
Ingo Molnar | d7e25f3 | 2007-02-16 01:28:24 -0800 | [diff] [blame] | 161 | irq_desc[irq].status |= IRQ_NOREQUEST | IRQ_NOPROBE; |
Thomas Gleixner | 4a2581a | 2006-07-01 22:30:09 +0100 | [diff] [blame] | 162 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | #ifdef CONFIG_SMP |
| 164 | bad_irq_desc.affinity = CPU_MASK_ALL; |
| 165 | bad_irq_desc.cpu = smp_processor_id(); |
| 166 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | init_arch_irq(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | } |
| 169 | |
Russell King | a054a81 | 2005-11-02 22:24:33 +0000 | [diff] [blame] | 170 | #ifdef CONFIG_HOTPLUG_CPU |
Thomas Gleixner | f7ede37 | 2006-07-11 22:54:34 +0100 | [diff] [blame] | 171 | |
Russell King | 10dd5ce | 2006-11-23 11:41:32 +0000 | [diff] [blame] | 172 | static void route_irq(struct irq_desc *desc, unsigned int irq, unsigned int cpu) |
Thomas Gleixner | f7ede37 | 2006-07-11 22:54:34 +0100 | [diff] [blame] | 173 | { |
| 174 | pr_debug("IRQ%u: moving from cpu%u to cpu%u\n", irq, desc->cpu, cpu); |
| 175 | |
| 176 | spin_lock_irq(&desc->lock); |
| 177 | desc->chip->set_affinity(irq, cpumask_of_cpu(cpu)); |
| 178 | spin_unlock_irq(&desc->lock); |
| 179 | } |
| 180 | |
Russell King | a054a81 | 2005-11-02 22:24:33 +0000 | [diff] [blame] | 181 | /* |
| 182 | * The CPU has been marked offline. Migrate IRQs off this CPU. If |
| 183 | * the affinity settings do not allow other CPUs, force them onto any |
| 184 | * available CPU. |
| 185 | */ |
| 186 | void migrate_irqs(void) |
| 187 | { |
| 188 | unsigned int i, cpu = smp_processor_id(); |
| 189 | |
| 190 | for (i = 0; i < NR_IRQS; i++) { |
Russell King | 10dd5ce | 2006-11-23 11:41:32 +0000 | [diff] [blame] | 191 | struct irq_desc *desc = irq_desc + i; |
Russell King | a054a81 | 2005-11-02 22:24:33 +0000 | [diff] [blame] | 192 | |
| 193 | if (desc->cpu == cpu) { |
| 194 | unsigned int newcpu = any_online_cpu(desc->affinity); |
| 195 | |
| 196 | if (newcpu == NR_CPUS) { |
| 197 | if (printk_ratelimit()) |
| 198 | printk(KERN_INFO "IRQ%u no longer affine to CPU%u\n", |
| 199 | i, cpu); |
| 200 | |
| 201 | cpus_setall(desc->affinity); |
| 202 | newcpu = any_online_cpu(desc->affinity); |
| 203 | } |
| 204 | |
| 205 | route_irq(desc, i, newcpu); |
| 206 | } |
| 207 | } |
| 208 | } |
| 209 | #endif /* CONFIG_HOTPLUG_CPU */ |