Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/irq/handle.c |
| 3 | * |
Ingo Molnar | a34db9b | 2006-06-29 02:24:50 -0700 | [diff] [blame] | 4 | * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar |
| 5 | * Copyright (C) 2005-2006, Thomas Gleixner, Russell King |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | * |
| 7 | * This file contains the core interrupt handling code. |
Ingo Molnar | a34db9b | 2006-06-29 02:24:50 -0700 | [diff] [blame] | 8 | * |
| 9 | * Detailed information is available in Documentation/DocBook/genericirq |
| 10 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | */ |
| 12 | |
| 13 | #include <linux/irq.h> |
| 14 | #include <linux/module.h> |
| 15 | #include <linux/random.h> |
| 16 | #include <linux/interrupt.h> |
| 17 | #include <linux/kernel_stat.h> |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 18 | #include <linux/rculist.h> |
| 19 | #include <linux/hash.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | |
| 21 | #include "internals.h" |
| 22 | |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 23 | /* |
| 24 | * lockdep: we want to handle all irq_desc locks as a single lock-class: |
| 25 | */ |
Yinghai Lu | 48a1b10 | 2008-12-11 00:15:01 -0800 | [diff] [blame] | 26 | struct lock_class_key irq_desc_lock_class; |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 27 | |
Thomas Gleixner | 6a6de9e | 2006-06-29 02:24:51 -0700 | [diff] [blame] | 28 | /** |
| 29 | * handle_bad_irq - handle spurious and unhandled irqs |
Henrik Kretzschmar | 43a1dd5 | 2006-08-31 21:27:44 -0700 | [diff] [blame] | 30 | * @irq: the interrupt number |
| 31 | * @desc: description of the interrupt |
Henrik Kretzschmar | 43a1dd5 | 2006-08-31 21:27:44 -0700 | [diff] [blame] | 32 | * |
| 33 | * Handles spurious and unhandled IRQ's. It also prints a debugmessage. |
Thomas Gleixner | 6a6de9e | 2006-06-29 02:24:51 -0700 | [diff] [blame] | 34 | */ |
Thomas Gleixner | d6c88a5 | 2008-10-15 15:27:23 +0200 | [diff] [blame] | 35 | void handle_bad_irq(unsigned int irq, struct irq_desc *desc) |
Thomas Gleixner | 6a6de9e | 2006-06-29 02:24:51 -0700 | [diff] [blame] | 36 | { |
Ingo Molnar | 43f7775 | 2006-06-29 02:24:58 -0700 | [diff] [blame] | 37 | print_irq_desc(irq, desc); |
Thomas Gleixner | d6c88a5 | 2008-10-15 15:27:23 +0200 | [diff] [blame] | 38 | kstat_incr_irqs_this_cpu(irq, desc); |
Thomas Gleixner | 6a6de9e | 2006-06-29 02:24:51 -0700 | [diff] [blame] | 39 | ack_bad_irq(irq); |
| 40 | } |
| 41 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | /* |
| 43 | * Linux has a controller-independent interrupt architecture. |
| 44 | * Every controller has a 'controller-template', that is used |
| 45 | * by the main code to do the right thing. Each driver-visible |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 46 | * interrupt source is transparently wired to the appropriate |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | * controller. Thus drivers need not be aware of the |
| 48 | * interrupt-controller. |
| 49 | * |
| 50 | * The code is designed to be easily extended with new/different |
| 51 | * interrupt controllers, without having to do assembly magic or |
| 52 | * having to touch the generic code. |
| 53 | * |
| 54 | * Controller mappings for all interrupt sources: |
| 55 | */ |
Yinghai Lu | 85c0f90 | 2008-08-19 20:49:47 -0700 | [diff] [blame] | 56 | int nr_irqs = NR_IRQS; |
Ingo Molnar | fa42d10 | 2008-08-19 20:50:30 -0700 | [diff] [blame] | 57 | EXPORT_SYMBOL_GPL(nr_irqs); |
Yinghai Lu | d60458b | 2008-08-19 20:50:00 -0700 | [diff] [blame] | 58 | |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 59 | void __init __attribute__((weak)) arch_early_irq_init(void) |
| 60 | { |
| 61 | } |
| 62 | |
| 63 | #ifdef CONFIG_SPARSE_IRQ |
| 64 | static struct irq_desc irq_desc_init = { |
| 65 | .irq = -1, |
| 66 | .status = IRQ_DISABLED, |
| 67 | .chip = &no_irq_chip, |
| 68 | .handle_irq = handle_bad_irq, |
| 69 | .depth = 1, |
| 70 | .lock = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock), |
| 71 | #ifdef CONFIG_SMP |
| 72 | .affinity = CPU_MASK_ALL |
| 73 | #endif |
| 74 | }; |
| 75 | |
Yinghai Lu | 48a1b10 | 2008-12-11 00:15:01 -0800 | [diff] [blame] | 76 | void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr) |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 77 | { |
| 78 | unsigned long bytes; |
| 79 | char *ptr; |
| 80 | int node; |
| 81 | |
| 82 | /* Compute how many bytes we need per irq and allocate them */ |
| 83 | bytes = nr * sizeof(unsigned int); |
| 84 | |
| 85 | node = cpu_to_node(cpu); |
| 86 | ptr = kzalloc_node(bytes, GFP_ATOMIC, node); |
| 87 | printk(KERN_DEBUG " alloc kstat_irqs on cpu %d node %d\n", cpu, node); |
| 88 | |
| 89 | if (ptr) |
| 90 | desc->kstat_irqs = (unsigned int *)ptr; |
| 91 | } |
| 92 | |
| 93 | void __attribute__((weak)) arch_init_chip_data(struct irq_desc *desc, int cpu) |
| 94 | { |
| 95 | } |
| 96 | |
| 97 | static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu) |
| 98 | { |
| 99 | memcpy(desc, &irq_desc_init, sizeof(struct irq_desc)); |
| 100 | desc->irq = irq; |
| 101 | #ifdef CONFIG_SMP |
| 102 | desc->cpu = cpu; |
| 103 | #endif |
| 104 | lockdep_set_class(&desc->lock, &irq_desc_lock_class); |
| 105 | init_kstat_irqs(desc, cpu, nr_cpu_ids); |
| 106 | if (!desc->kstat_irqs) { |
| 107 | printk(KERN_ERR "can not alloc kstat_irqs\n"); |
| 108 | BUG_ON(1); |
| 109 | } |
| 110 | arch_init_chip_data(desc, cpu); |
| 111 | } |
| 112 | |
| 113 | /* |
| 114 | * Protect the sparse_irqs: |
| 115 | */ |
Yinghai Lu | 48a1b10 | 2008-12-11 00:15:01 -0800 | [diff] [blame] | 116 | DEFINE_SPINLOCK(sparse_irq_lock); |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 117 | |
| 118 | struct irq_desc *irq_desc_ptrs[NR_IRQS] __read_mostly; |
| 119 | |
Yinghai Lu | 99d093d | 2008-12-05 18:58:32 -0800 | [diff] [blame] | 120 | static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = { |
| 121 | [0 ... NR_IRQS_LEGACY-1] = { |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 122 | .irq = -1, |
| 123 | .status = IRQ_DISABLED, |
| 124 | .chip = &no_irq_chip, |
| 125 | .handle_irq = handle_bad_irq, |
| 126 | .depth = 1, |
| 127 | .lock = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock), |
| 128 | #ifdef CONFIG_SMP |
| 129 | .affinity = CPU_MASK_ALL |
| 130 | #endif |
| 131 | } |
| 132 | }; |
| 133 | |
| 134 | /* FIXME: use bootmem alloc ...*/ |
Yinghai Lu | 99d093d | 2008-12-05 18:58:32 -0800 | [diff] [blame] | 135 | static unsigned int kstat_irqs_legacy[NR_IRQS_LEGACY][NR_CPUS]; |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 136 | |
| 137 | void __init early_irq_init(void) |
| 138 | { |
| 139 | struct irq_desc *desc; |
| 140 | int legacy_count; |
| 141 | int i; |
| 142 | |
| 143 | desc = irq_desc_legacy; |
| 144 | legacy_count = ARRAY_SIZE(irq_desc_legacy); |
| 145 | |
| 146 | for (i = 0; i < legacy_count; i++) { |
| 147 | desc[i].irq = i; |
| 148 | desc[i].kstat_irqs = kstat_irqs_legacy[i]; |
| 149 | |
| 150 | irq_desc_ptrs[i] = desc + i; |
| 151 | } |
| 152 | |
| 153 | for (i = legacy_count; i < NR_IRQS; i++) |
| 154 | irq_desc_ptrs[i] = NULL; |
| 155 | |
| 156 | arch_early_irq_init(); |
| 157 | } |
| 158 | |
| 159 | struct irq_desc *irq_to_desc(unsigned int irq) |
| 160 | { |
| 161 | return (irq < NR_IRQS) ? irq_desc_ptrs[irq] : NULL; |
| 162 | } |
| 163 | |
| 164 | struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu) |
| 165 | { |
| 166 | struct irq_desc *desc; |
| 167 | unsigned long flags; |
| 168 | int node; |
| 169 | |
| 170 | if (irq >= NR_IRQS) { |
| 171 | printk(KERN_WARNING "irq >= NR_IRQS in irq_to_desc_alloc: %d %d\n", |
| 172 | irq, NR_IRQS); |
| 173 | WARN_ON(1); |
| 174 | return NULL; |
| 175 | } |
| 176 | |
| 177 | desc = irq_desc_ptrs[irq]; |
| 178 | if (desc) |
| 179 | return desc; |
| 180 | |
| 181 | spin_lock_irqsave(&sparse_irq_lock, flags); |
| 182 | |
| 183 | /* We have to check it to avoid races with another CPU */ |
| 184 | desc = irq_desc_ptrs[irq]; |
| 185 | if (desc) |
| 186 | goto out_unlock; |
| 187 | |
| 188 | node = cpu_to_node(cpu); |
| 189 | desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node); |
| 190 | printk(KERN_DEBUG " alloc irq_desc for %d on cpu %d node %d\n", |
| 191 | irq, cpu, node); |
| 192 | if (!desc) { |
| 193 | printk(KERN_ERR "can not alloc irq_desc\n"); |
| 194 | BUG_ON(1); |
| 195 | } |
| 196 | init_one_irq_desc(irq, desc, cpu); |
| 197 | |
| 198 | irq_desc_ptrs[irq] = desc; |
| 199 | |
| 200 | out_unlock: |
| 201 | spin_unlock_irqrestore(&sparse_irq_lock, flags); |
| 202 | |
| 203 | return desc; |
| 204 | } |
| 205 | |
KOSAKI Motohiro | f9af0e7 | 2008-12-26 12:24:24 +0900 | [diff] [blame^] | 206 | #else /* !CONFIG_SPARSE_IRQ */ |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 207 | |
Ravikiran G Thirumalai | e729aa1 | 2007-05-08 00:29:13 -0700 | [diff] [blame] | 208 | struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | [0 ... NR_IRQS-1] = { |
Zhang, Yanmin | 4f167fb | 2005-05-16 21:53:43 -0700 | [diff] [blame] | 210 | .status = IRQ_DISABLED, |
Ingo Molnar | f1c2662 | 2006-06-29 02:24:57 -0700 | [diff] [blame] | 211 | .chip = &no_irq_chip, |
Ingo Molnar | 7a55713 | 2006-06-29 02:24:54 -0700 | [diff] [blame] | 212 | .handle_irq = handle_bad_irq, |
Thomas Gleixner | 94d39e1 | 2006-06-29 02:24:50 -0700 | [diff] [blame] | 213 | .depth = 1, |
Yinghai Lu | aac3f2b | 2008-09-24 19:04:35 -0700 | [diff] [blame] | 214 | .lock = __SPIN_LOCK_UNLOCKED(irq_desc->lock), |
Ingo Molnar | a53da52 | 2006-06-29 02:24:38 -0700 | [diff] [blame] | 215 | #ifdef CONFIG_SMP |
| 216 | .affinity = CPU_MASK_ALL |
| 217 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | } |
| 219 | }; |
Yinghai Lu | 08678b0 | 2008-08-19 20:50:05 -0700 | [diff] [blame] | 220 | |
KOSAKI Motohiro | f9af0e7 | 2008-12-26 12:24:24 +0900 | [diff] [blame^] | 221 | struct irq_desc *irq_to_desc(unsigned int irq) |
| 222 | { |
| 223 | return (irq < NR_IRQS) ? irq_desc + irq : NULL; |
| 224 | } |
| 225 | |
| 226 | struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu) |
| 227 | { |
| 228 | return irq_to_desc(irq); |
| 229 | } |
| 230 | #endif /* !CONFIG_SPARSE_IRQ */ |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 231 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | /* |
Ingo Molnar | 77a5afe | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 233 | * What should we do if we get a hw irq event on an illegal vector? |
| 234 | * Each architecture has to answer this themself. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | */ |
Ingo Molnar | 77a5afe | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 236 | static void ack_bad(unsigned int irq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | { |
Thomas Gleixner | d3c6004 | 2008-10-16 09:55:00 +0200 | [diff] [blame] | 238 | struct irq_desc *desc = irq_to_desc(irq); |
Yinghai Lu | 08678b0 | 2008-08-19 20:50:05 -0700 | [diff] [blame] | 239 | |
Yinghai Lu | 08678b0 | 2008-08-19 20:50:05 -0700 | [diff] [blame] | 240 | print_irq_desc(irq, desc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | ack_bad_irq(irq); |
| 242 | } |
| 243 | |
Ingo Molnar | 77a5afe | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 244 | /* |
| 245 | * NOP functions |
| 246 | */ |
| 247 | static void noop(unsigned int irq) |
| 248 | { |
| 249 | } |
| 250 | |
| 251 | static unsigned int noop_ret(unsigned int irq) |
| 252 | { |
| 253 | return 0; |
| 254 | } |
| 255 | |
| 256 | /* |
| 257 | * Generic no controller implementation |
| 258 | */ |
Ingo Molnar | f1c2662 | 2006-06-29 02:24:57 -0700 | [diff] [blame] | 259 | struct irq_chip no_irq_chip = { |
| 260 | .name = "none", |
Ingo Molnar | 77a5afe | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 261 | .startup = noop_ret, |
| 262 | .shutdown = noop, |
| 263 | .enable = noop, |
| 264 | .disable = noop, |
| 265 | .ack = ack_bad, |
| 266 | .end = noop, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | }; |
| 268 | |
| 269 | /* |
Thomas Gleixner | f8b5473 | 2006-07-01 22:30:08 +0100 | [diff] [blame] | 270 | * Generic dummy implementation which can be used for |
| 271 | * real dumb interrupt sources |
| 272 | */ |
| 273 | struct irq_chip dummy_irq_chip = { |
| 274 | .name = "dummy", |
| 275 | .startup = noop_ret, |
| 276 | .shutdown = noop, |
| 277 | .enable = noop, |
| 278 | .disable = noop, |
| 279 | .ack = noop, |
| 280 | .mask = noop, |
| 281 | .unmask = noop, |
| 282 | .end = noop, |
| 283 | }; |
| 284 | |
| 285 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | * Special, empty irq handler: |
| 287 | */ |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 288 | irqreturn_t no_action(int cpl, void *dev_id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | { |
| 290 | return IRQ_NONE; |
| 291 | } |
| 292 | |
Ingo Molnar | 8d28bc7 | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 293 | /** |
| 294 | * handle_IRQ_event - irq action chain handler |
| 295 | * @irq: the interrupt number |
Ingo Molnar | 8d28bc7 | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 296 | * @action: the interrupt action chain for this irq |
| 297 | * |
| 298 | * Handles the action chain of an irq event |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 299 | */ |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 300 | irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | { |
Jan Beulich | 908dcec | 2006-06-23 02:06:00 -0700 | [diff] [blame] | 302 | irqreturn_t ret, retval = IRQ_NONE; |
| 303 | unsigned int status = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | |
Thomas Gleixner | 3cca53b | 2006-07-01 19:29:31 -0700 | [diff] [blame] | 305 | if (!(action->flags & IRQF_DISABLED)) |
Ingo Molnar | 366c7f5 | 2006-07-03 00:25:25 -0700 | [diff] [blame] | 306 | local_irq_enable_in_hardirq(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | |
| 308 | do { |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 309 | ret = action->handler(irq, action->dev_id); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | if (ret == IRQ_HANDLED) |
| 311 | status |= action->flags; |
| 312 | retval |= ret; |
| 313 | action = action->next; |
| 314 | } while (action); |
| 315 | |
Thomas Gleixner | 3cca53b | 2006-07-01 19:29:31 -0700 | [diff] [blame] | 316 | if (status & IRQF_SAMPLE_RANDOM) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | add_interrupt_randomness(irq); |
| 318 | local_irq_disable(); |
| 319 | |
| 320 | return retval; |
| 321 | } |
| 322 | |
David Howells | af8c65b | 2006-09-25 23:32:07 -0700 | [diff] [blame] | 323 | #ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ |
Ingo Molnar | 8d28bc7 | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 324 | /** |
| 325 | * __do_IRQ - original all in one highlevel IRQ handler |
| 326 | * @irq: the interrupt number |
Ingo Molnar | 8d28bc7 | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 327 | * |
| 328 | * __do_IRQ handles all normal device IRQ's (the special |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | * SMP cross-CPU interrupts have their own specific |
| 330 | * handlers). |
Ingo Molnar | 8d28bc7 | 2006-06-29 02:24:46 -0700 | [diff] [blame] | 331 | * |
| 332 | * This is the original x86 implementation which is used for every |
| 333 | * interrupt type. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | */ |
Harvey Harrison | 7ad5b3a | 2008-02-08 04:19:53 -0800 | [diff] [blame] | 335 | unsigned int __do_IRQ(unsigned int irq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | { |
Yinghai Lu | 08678b0 | 2008-08-19 20:50:05 -0700 | [diff] [blame] | 337 | struct irq_desc *desc = irq_to_desc(irq); |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 338 | struct irqaction *action; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | unsigned int status; |
| 340 | |
Thomas Gleixner | d6c88a5 | 2008-10-15 15:27:23 +0200 | [diff] [blame] | 341 | kstat_incr_irqs_this_cpu(irq, desc); |
| 342 | |
Karsten Wiese | f26fdd5 | 2005-09-06 15:17:25 -0700 | [diff] [blame] | 343 | if (CHECK_IRQ_PER_CPU(desc->status)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | irqreturn_t action_ret; |
| 345 | |
| 346 | /* |
| 347 | * No locking required for CPU-local interrupts: |
| 348 | */ |
Yinghai Lu | 48a1b10 | 2008-12-11 00:15:01 -0800 | [diff] [blame] | 349 | if (desc->chip->ack) { |
Ingo Molnar | d1bef4e | 2006-06-29 02:24:36 -0700 | [diff] [blame] | 350 | desc->chip->ack(irq); |
Yinghai Lu | 48a1b10 | 2008-12-11 00:15:01 -0800 | [diff] [blame] | 351 | /* get new one */ |
| 352 | desc = irq_remap_to_desc(irq, desc); |
| 353 | } |
Russ Anderson | c642b83 | 2007-11-14 17:00:15 -0800 | [diff] [blame] | 354 | if (likely(!(desc->status & IRQ_DISABLED))) { |
| 355 | action_ret = handle_IRQ_event(irq, desc->action); |
| 356 | if (!noirqdebug) |
| 357 | note_interrupt(irq, desc, action_ret); |
| 358 | } |
Ingo Molnar | d1bef4e | 2006-06-29 02:24:36 -0700 | [diff] [blame] | 359 | desc->chip->end(irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | return 1; |
| 361 | } |
| 362 | |
| 363 | spin_lock(&desc->lock); |
Yinghai Lu | 48a1b10 | 2008-12-11 00:15:01 -0800 | [diff] [blame] | 364 | if (desc->chip->ack) { |
Ingo Molnar | d1bef4e | 2006-06-29 02:24:36 -0700 | [diff] [blame] | 365 | desc->chip->ack(irq); |
Yinghai Lu | 48a1b10 | 2008-12-11 00:15:01 -0800 | [diff] [blame] | 366 | desc = irq_remap_to_desc(irq, desc); |
| 367 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | /* |
| 369 | * REPLAY is when Linux resends an IRQ that was dropped earlier |
| 370 | * WAITING is used by probe to mark irqs that are being tested |
| 371 | */ |
| 372 | status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING); |
| 373 | status |= IRQ_PENDING; /* we _want_ to handle it */ |
| 374 | |
| 375 | /* |
| 376 | * If the IRQ is disabled for whatever reason, we cannot |
| 377 | * use the action we have. |
| 378 | */ |
| 379 | action = NULL; |
| 380 | if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) { |
| 381 | action = desc->action; |
| 382 | status &= ~IRQ_PENDING; /* we commit to handling */ |
| 383 | status |= IRQ_INPROGRESS; /* we are handling it */ |
| 384 | } |
| 385 | desc->status = status; |
| 386 | |
| 387 | /* |
| 388 | * If there is no IRQ handler or it was disabled, exit early. |
| 389 | * Since we set PENDING, if another processor is handling |
| 390 | * a different instance of this same irq, the other processor |
| 391 | * will take care of it. |
| 392 | */ |
| 393 | if (unlikely(!action)) |
| 394 | goto out; |
| 395 | |
| 396 | /* |
| 397 | * Edge triggered interrupts need to remember |
| 398 | * pending events. |
| 399 | * This applies to any hw interrupts that allow a second |
| 400 | * instance of the same irq to arrive while we are in do_IRQ |
| 401 | * or in the handler. But the code here only handles the _second_ |
| 402 | * instance of the irq, not the third or fourth. So it is mostly |
| 403 | * useful for irq hardware that does not mask cleanly in an |
| 404 | * SMP environment. |
| 405 | */ |
| 406 | for (;;) { |
| 407 | irqreturn_t action_ret; |
| 408 | |
| 409 | spin_unlock(&desc->lock); |
| 410 | |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 411 | action_ret = handle_IRQ_event(irq, action); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | if (!noirqdebug) |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 413 | note_interrupt(irq, desc, action_ret); |
Linus Torvalds | b42172f | 2006-11-22 09:32:06 -0800 | [diff] [blame] | 414 | |
| 415 | spin_lock(&desc->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 416 | if (likely(!(desc->status & IRQ_PENDING))) |
| 417 | break; |
| 418 | desc->status &= ~IRQ_PENDING; |
| 419 | } |
| 420 | desc->status &= ~IRQ_INPROGRESS; |
| 421 | |
| 422 | out: |
| 423 | /* |
| 424 | * The ->end() handler has to deal with interrupts which got |
| 425 | * disabled while the handler was running. |
| 426 | */ |
Ingo Molnar | d1bef4e | 2006-06-29 02:24:36 -0700 | [diff] [blame] | 427 | desc->chip->end(irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 428 | spin_unlock(&desc->lock); |
| 429 | |
| 430 | return 1; |
| 431 | } |
David Howells | af8c65b | 2006-09-25 23:32:07 -0700 | [diff] [blame] | 432 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | |
Ingo Molnar | 243c762 | 2006-07-03 00:25:06 -0700 | [diff] [blame] | 434 | void early_init_irq_lock_class(void) |
| 435 | { |
Thomas Gleixner | 10e5808 | 2008-10-16 14:19:04 +0200 | [diff] [blame] | 436 | struct irq_desc *desc; |
Ingo Molnar | 243c762 | 2006-07-03 00:25:06 -0700 | [diff] [blame] | 437 | int i; |
| 438 | |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 439 | for_each_irq_desc(i, desc) { |
| 440 | if (!desc) |
| 441 | continue; |
| 442 | |
Thomas Gleixner | 10e5808 | 2008-10-16 14:19:04 +0200 | [diff] [blame] | 443 | lockdep_set_class(&desc->lock, &irq_desc_lock_class); |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 444 | } |
Yinghai Lu | 08678b0 | 2008-08-19 20:50:05 -0700 | [diff] [blame] | 445 | } |
Yinghai Lu | 0b8f1ef | 2008-12-05 18:58:31 -0800 | [diff] [blame] | 446 | |
| 447 | #ifdef CONFIG_SPARSE_IRQ |
| 448 | unsigned int kstat_irqs_cpu(unsigned int irq, int cpu) |
| 449 | { |
| 450 | struct irq_desc *desc = irq_to_desc(irq); |
| 451 | return desc->kstat_irqs[cpu]; |
| 452 | } |
| 453 | #endif |
| 454 | EXPORT_SYMBOL(kstat_irqs_cpu); |
| 455 | |