1 /* interrupt.h */ 2 #ifndef _LINUX_INTERRUPT_H 3 #define _LINUX_INTERRUPT_H 4 5 #include <linux/kernel.h> 6 #include <linux/linkage.h> 7 #include <linux/bitops.h> 8 #include <linux/preempt.h> 9 #include <linux/cpumask.h> 10 #include <linux/irqreturn.h> 11 #include <linux/hardirq.h> 12 #include <linux/sched.h> 13 #include <linux/irqflags.h> 14 #include <linux/bottom_half.h> 15 #include <linux/device.h> 16 #include <asm/atomic.h> 17 #include <asm/ptrace.h> 18 #include <asm/system.h> 19 20 /* 21 * These correspond to the IORESOURCE_IRQ_* defines in 22 * linux/ioport.h to select the interrupt line behaviour. When 23 * requesting an interrupt without specifying a IRQF_TRIGGER, the 24 * setting should be assumed to be "as already configured", which 25 * may be as per machine or firmware initialisation. 26 */ 27 #define IRQF_TRIGGER_NONE 0x00000000 28 #define IRQF_TRIGGER_RISING 0x00000001 29 #define IRQF_TRIGGER_FALLING 0x00000002 30 #define IRQF_TRIGGER_HIGH 0x00000004 31 #define IRQF_TRIGGER_LOW 0x00000008 32 #define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \ 33 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING) 34 #define IRQF_TRIGGER_PROBE 0x00000010 35 36 /* 37 * These flags used only by the kernel as part of the 38 * irq handling routines. 39 * 40 * IRQF_DISABLED - keep irqs disabled when calling the action handler 41 * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator 42 * IRQF_SHARED - allow sharing the irq among several devices 43 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur 44 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt 45 * IRQF_PERCPU - Interrupt is per cpu 46 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing 47 */ 48 #define IRQF_DISABLED 0x00000020 49 #define IRQF_SAMPLE_RANDOM 0x00000040 50 #define IRQF_SHARED 0x00000080 51 #define IRQF_PROBE_SHARED 0x00000100 52 #define IRQF_TIMER 0x00000200 53 #define IRQF_PERCPU 0x00000400 54 #define IRQF_NOBALANCING 0x00000800 55 56 /* 57 * Migration helpers. Scheduled for removal in 1/2007 58 * Do not use for new code ! 59 */ 60 #define SA_INTERRUPT IRQF_DISABLED 61 #define SA_SAMPLE_RANDOM IRQF_SAMPLE_RANDOM 62 #define SA_SHIRQ IRQF_SHARED 63 #define SA_PROBEIRQ IRQF_PROBE_SHARED 64 #define SA_PERCPU IRQF_PERCPU 65 66 #define SA_TRIGGER_LOW IRQF_TRIGGER_LOW 67 #define SA_TRIGGER_HIGH IRQF_TRIGGER_HIGH 68 #define SA_TRIGGER_FALLING IRQF_TRIGGER_FALLING 69 #define SA_TRIGGER_RISING IRQF_TRIGGER_RISING 70 #define SA_TRIGGER_MASK IRQF_TRIGGER_MASK 71 72 typedef irqreturn_t (*irq_handler_t)(int, void *); 73 74 struct irqaction { 75 irq_handler_t handler; 76 unsigned long flags; 77 cpumask_t mask; 78 const char *name; 79 void *dev_id; 80 struct irqaction *next; 81 int irq; 82 struct proc_dir_entry *dir; 83 }; 84 85 extern irqreturn_t no_action(int cpl, void *dev_id); 86 extern int __must_check request_irq(unsigned int, irq_handler_t handler, 87 unsigned long, const char *, void *); 88 extern void free_irq(unsigned int, void *); 89 90 extern int __must_check devm_request_irq(struct device *dev, unsigned int irq, 91 irq_handler_t handler, unsigned long irqflags, 92 const char *devname, void *dev_id); 93 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id); 94 95 /* 96 * On lockdep we dont want to enable hardirqs in hardirq 97 * context. Use local_irq_enable_in_hardirq() to annotate 98 * kernel code that has to do this nevertheless (pretty much 99 * the only valid case is for old/broken hardware that is 100 * insanely slow). 101 * 102 * NOTE: in theory this might break fragile code that relies 103 * on hardirq delivery - in practice we dont seem to have such 104 * places left. So the only effect should be slightly increased 105 * irqs-off latencies. 106 */ 107 #ifdef CONFIG_LOCKDEP 108 # define local_irq_enable_in_hardirq() do { } while (0) 109 #else 110 # define local_irq_enable_in_hardirq() local_irq_enable() 111 #endif 112 113 #ifdef CONFIG_GENERIC_HARDIRQS 114 extern void disable_irq_nosync(unsigned int irq); 115 extern void disable_irq(unsigned int irq); 116 extern void enable_irq(unsigned int irq); 117 118 /* 119 * Special lockdep variants of irq disabling/enabling. 120 * These should be used for locking constructs that 121 * know that a particular irq context which is disabled, 122 * and which is the only irq-context user of a lock, 123 * that it's safe to take the lock in the irq-disabled 124 * section without disabling hardirqs. 125 * 126 * On !CONFIG_LOCKDEP they are equivalent to the normal 127 * irq disable/enable methods. 128 */ 129 static inline void disable_irq_nosync_lockdep(unsigned int irq) 130 { 131 disable_irq_nosync(irq); 132 #ifdef CONFIG_LOCKDEP 133 local_irq_disable(); 134 #endif 135 } 136 137 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags) 138 { 139 disable_irq_nosync(irq); 140 #ifdef CONFIG_LOCKDEP 141 local_irq_save(*flags); 142 #endif 143 } 144 145 static inline void disable_irq_lockdep(unsigned int irq) 146 { 147 disable_irq(irq); 148 #ifdef CONFIG_LOCKDEP 149 local_irq_disable(); 150 #endif 151 } 152 153 static inline void enable_irq_lockdep(unsigned int irq) 154 { 155 #ifdef CONFIG_LOCKDEP 156 local_irq_enable(); 157 #endif 158 enable_irq(irq); 159 } 160 161 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags) 162 { 163 #ifdef CONFIG_LOCKDEP 164 local_irq_restore(*flags); 165 #endif 166 enable_irq(irq); 167 } 168 169 /* IRQ wakeup (PM) control: */ 170 extern int set_irq_wake(unsigned int irq, unsigned int on); 171 172 static inline int enable_irq_wake(unsigned int irq) 173 { 174 return set_irq_wake(irq, 1); 175 } 176 177 static inline int disable_irq_wake(unsigned int irq) 178 { 179 return set_irq_wake(irq, 0); 180 } 181 182 #else /* !CONFIG_GENERIC_HARDIRQS */ 183 /* 184 * NOTE: non-genirq architectures, if they want to support the lock 185 * validator need to define the methods below in their asm/irq.h 186 * files, under an #ifdef CONFIG_LOCKDEP section. 187 */ 188 #ifndef CONFIG_LOCKDEP 189 # define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq) 190 # define disable_irq_nosync_lockdep_irqsave(irq, flags) \ 191 disable_irq_nosync(irq) 192 # define disable_irq_lockdep(irq) disable_irq(irq) 193 # define enable_irq_lockdep(irq) enable_irq(irq) 194 # define enable_irq_lockdep_irqrestore(irq, flags) \ 195 enable_irq(irq) 196 # endif 197 198 #endif /* CONFIG_GENERIC_HARDIRQS */ 199 200 #ifndef __ARCH_SET_SOFTIRQ_PENDING 201 #define set_softirq_pending(x) (local_softirq_pending() = (x)) 202 #define or_softirq_pending(x) (local_softirq_pending() |= (x)) 203 #endif 204 205 /* 206 * Temporary defines for UP kernels, until all code gets fixed. 207 */ 208 #ifndef CONFIG_SMP 209 static inline void __deprecated cli(void) 210 { 211 local_irq_disable(); 212 } 213 static inline void __deprecated sti(void) 214 { 215 local_irq_enable(); 216 } 217 static inline void __deprecated save_flags(unsigned long *x) 218 { 219 local_save_flags(*x); 220 } 221 #define save_flags(x) save_flags(&x) 222 static inline void __deprecated restore_flags(unsigned long x) 223 { 224 local_irq_restore(x); 225 } 226 227 static inline void __deprecated save_and_cli(unsigned long *x) 228 { 229 local_irq_save(*x); 230 } 231 #define save_and_cli(x) save_and_cli(&x) 232 #endif /* CONFIG_SMP */ 233 234 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high 235 frequency threaded job scheduling. For almost all the purposes 236 tasklets are more than enough. F.e. all serial device BHs et 237 al. should be converted to tasklets, not to softirqs. 238 */ 239 240 enum 241 { 242 HI_SOFTIRQ=0, 243 TIMER_SOFTIRQ, 244 NET_TX_SOFTIRQ, 245 NET_RX_SOFTIRQ, 246 BLOCK_SOFTIRQ, 247 TASKLET_SOFTIRQ, 248 SCHED_SOFTIRQ, 249 #ifdef CONFIG_HIGH_RES_TIMERS 250 HRTIMER_SOFTIRQ, 251 #endif 252 }; 253 254 /* softirq mask and active fields moved to irq_cpustat_t in 255 * asm/hardirq.h to get better cache usage. KAO 256 */ 257 258 struct softirq_action 259 { 260 void (*action)(struct softirq_action *); 261 void *data; 262 }; 263 264 asmlinkage void do_softirq(void); 265 extern void open_softirq(int nr, void (*action)(struct softirq_action*), void *data); 266 extern void softirq_init(void); 267 #define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0) 268 extern void FASTCALL(raise_softirq_irqoff(unsigned int nr)); 269 extern void FASTCALL(raise_softirq(unsigned int nr)); 270 271 272 /* Tasklets --- multithreaded analogue of BHs. 273 274 Main feature differing them of generic softirqs: tasklet 275 is running only on one CPU simultaneously. 276 277 Main feature differing them of BHs: different tasklets 278 may be run simultaneously on different CPUs. 279 280 Properties: 281 * If tasklet_schedule() is called, then tasklet is guaranteed 282 to be executed on some cpu at least once after this. 283 * If the tasklet is already scheduled, but its excecution is still not 284 started, it will be executed only once. 285 * If this tasklet is already running on another CPU (or schedule is called 286 from tasklet itself), it is rescheduled for later. 287 * Tasklet is strictly serialized wrt itself, but not 288 wrt another tasklets. If client needs some intertask synchronization, 289 he makes it with spinlocks. 290 */ 291 292 struct tasklet_struct 293 { 294 struct tasklet_struct *next; 295 unsigned long state; 296 atomic_t count; 297 void (*func)(unsigned long); 298 unsigned long data; 299 }; 300 301 #define DECLARE_TASKLET(name, func, data) \ 302 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data } 303 304 #define DECLARE_TASKLET_DISABLED(name, func, data) \ 305 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data } 306 307 308 enum 309 { 310 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */ 311 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */ 312 }; 313 314 #ifdef CONFIG_SMP 315 static inline int tasklet_trylock(struct tasklet_struct *t) 316 { 317 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state); 318 } 319 320 static inline void tasklet_unlock(struct tasklet_struct *t) 321 { 322 smp_mb__before_clear_bit(); 323 clear_bit(TASKLET_STATE_RUN, &(t)->state); 324 } 325 326 static inline void tasklet_unlock_wait(struct tasklet_struct *t) 327 { 328 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } 329 } 330 #else 331 #define tasklet_trylock(t) 1 332 #define tasklet_unlock_wait(t) do { } while (0) 333 #define tasklet_unlock(t) do { } while (0) 334 #endif 335 336 extern void FASTCALL(__tasklet_schedule(struct tasklet_struct *t)); 337 338 static inline void tasklet_schedule(struct tasklet_struct *t) 339 { 340 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 341 __tasklet_schedule(t); 342 } 343 344 extern void FASTCALL(__tasklet_hi_schedule(struct tasklet_struct *t)); 345 346 static inline void tasklet_hi_schedule(struct tasklet_struct *t) 347 { 348 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 349 __tasklet_hi_schedule(t); 350 } 351 352 353 static inline void tasklet_disable_nosync(struct tasklet_struct *t) 354 { 355 atomic_inc(&t->count); 356 smp_mb__after_atomic_inc(); 357 } 358 359 static inline void tasklet_disable(struct tasklet_struct *t) 360 { 361 tasklet_disable_nosync(t); 362 tasklet_unlock_wait(t); 363 smp_mb(); 364 } 365 366 static inline void tasklet_enable(struct tasklet_struct *t) 367 { 368 smp_mb__before_atomic_dec(); 369 atomic_dec(&t->count); 370 } 371 372 static inline void tasklet_hi_enable(struct tasklet_struct *t) 373 { 374 smp_mb__before_atomic_dec(); 375 atomic_dec(&t->count); 376 } 377 378 extern void tasklet_kill(struct tasklet_struct *t); 379 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu); 380 extern void tasklet_init(struct tasklet_struct *t, 381 void (*func)(unsigned long), unsigned long data); 382 383 /* 384 * Autoprobing for irqs: 385 * 386 * probe_irq_on() and probe_irq_off() provide robust primitives 387 * for accurate IRQ probing during kernel initialization. They are 388 * reasonably simple to use, are not "fooled" by spurious interrupts, 389 * and, unlike other attempts at IRQ probing, they do not get hung on 390 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards). 391 * 392 * For reasonably foolproof probing, use them as follows: 393 * 394 * 1. clear and/or mask the device's internal interrupt. 395 * 2. sti(); 396 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs 397 * 4. enable the device and cause it to trigger an interrupt. 398 * 5. wait for the device to interrupt, using non-intrusive polling or a delay. 399 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple 400 * 7. service the device to clear its pending interrupt. 401 * 8. loop again if paranoia is required. 402 * 403 * probe_irq_on() returns a mask of allocated irq's. 404 * 405 * probe_irq_off() takes the mask as a parameter, 406 * and returns the irq number which occurred, 407 * or zero if none occurred, or a negative irq number 408 * if more than one irq occurred. 409 */ 410 411 #if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE) 412 static inline unsigned long probe_irq_on(void) 413 { 414 return 0; 415 } 416 static inline int probe_irq_off(unsigned long val) 417 { 418 return 0; 419 } 420 static inline unsigned int probe_irq_mask(unsigned long val) 421 { 422 return 0; 423 } 424 #else 425 extern unsigned long probe_irq_on(void); /* returns 0 on failure */ 426 extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */ 427 extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */ 428 #endif 429 430 #ifdef CONFIG_PROC_FS 431 /* Initialize /proc/irq/ */ 432 extern void init_irq_proc(void); 433 #else 434 static inline void init_irq_proc(void) 435 { 436 } 437 #endif 438 439 #endif 440