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 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 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_lockdep(irq) disable_irq(irq) 191 # define enable_irq_lockdep(irq) enable_irq(irq) 192 # endif 193 194 #endif /* CONFIG_GENERIC_HARDIRQS */ 195 196 #ifndef __ARCH_SET_SOFTIRQ_PENDING 197 #define set_softirq_pending(x) (local_softirq_pending() = (x)) 198 #define or_softirq_pending(x) (local_softirq_pending() |= (x)) 199 #endif 200 201 /* 202 * Temporary defines for UP kernels, until all code gets fixed. 203 */ 204 #ifndef CONFIG_SMP 205 static inline void __deprecated cli(void) 206 { 207 local_irq_disable(); 208 } 209 static inline void __deprecated sti(void) 210 { 211 local_irq_enable(); 212 } 213 static inline void __deprecated save_flags(unsigned long *x) 214 { 215 local_save_flags(*x); 216 } 217 #define save_flags(x) save_flags(&x) 218 static inline void __deprecated restore_flags(unsigned long x) 219 { 220 local_irq_restore(x); 221 } 222 223 static inline void __deprecated save_and_cli(unsigned long *x) 224 { 225 local_irq_save(*x); 226 } 227 #define save_and_cli(x) save_and_cli(&x) 228 #endif /* CONFIG_SMP */ 229 230 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high 231 frequency threaded job scheduling. For almost all the purposes 232 tasklets are more than enough. F.e. all serial device BHs et 233 al. should be converted to tasklets, not to softirqs. 234 */ 235 236 enum 237 { 238 HI_SOFTIRQ=0, 239 TIMER_SOFTIRQ, 240 NET_TX_SOFTIRQ, 241 NET_RX_SOFTIRQ, 242 BLOCK_SOFTIRQ, 243 TASKLET_SOFTIRQ, 244 SCHED_SOFTIRQ, 245 #ifdef CONFIG_HIGH_RES_TIMERS 246 HRTIMER_SOFTIRQ, 247 #endif 248 }; 249 250 /* softirq mask and active fields moved to irq_cpustat_t in 251 * asm/hardirq.h to get better cache usage. KAO 252 */ 253 254 struct softirq_action 255 { 256 void (*action)(struct softirq_action *); 257 void *data; 258 }; 259 260 asmlinkage void do_softirq(void); 261 extern void open_softirq(int nr, void (*action)(struct softirq_action*), void *data); 262 extern void softirq_init(void); 263 #define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0) 264 extern void FASTCALL(raise_softirq_irqoff(unsigned int nr)); 265 extern void FASTCALL(raise_softirq(unsigned int nr)); 266 267 268 /* Tasklets --- multithreaded analogue of BHs. 269 270 Main feature differing them of generic softirqs: tasklet 271 is running only on one CPU simultaneously. 272 273 Main feature differing them of BHs: different tasklets 274 may be run simultaneously on different CPUs. 275 276 Properties: 277 * If tasklet_schedule() is called, then tasklet is guaranteed 278 to be executed on some cpu at least once after this. 279 * If the tasklet is already scheduled, but its excecution is still not 280 started, it will be executed only once. 281 * If this tasklet is already running on another CPU (or schedule is called 282 from tasklet itself), it is rescheduled for later. 283 * Tasklet is strictly serialized wrt itself, but not 284 wrt another tasklets. If client needs some intertask synchronization, 285 he makes it with spinlocks. 286 */ 287 288 struct tasklet_struct 289 { 290 struct tasklet_struct *next; 291 unsigned long state; 292 atomic_t count; 293 void (*func)(unsigned long); 294 unsigned long data; 295 }; 296 297 #define DECLARE_TASKLET(name, func, data) \ 298 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data } 299 300 #define DECLARE_TASKLET_DISABLED(name, func, data) \ 301 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data } 302 303 304 enum 305 { 306 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */ 307 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */ 308 }; 309 310 #ifdef CONFIG_SMP 311 static inline int tasklet_trylock(struct tasklet_struct *t) 312 { 313 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state); 314 } 315 316 static inline void tasklet_unlock(struct tasklet_struct *t) 317 { 318 smp_mb__before_clear_bit(); 319 clear_bit(TASKLET_STATE_RUN, &(t)->state); 320 } 321 322 static inline void tasklet_unlock_wait(struct tasklet_struct *t) 323 { 324 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } 325 } 326 #else 327 #define tasklet_trylock(t) 1 328 #define tasklet_unlock_wait(t) do { } while (0) 329 #define tasklet_unlock(t) do { } while (0) 330 #endif 331 332 extern void FASTCALL(__tasklet_schedule(struct tasklet_struct *t)); 333 334 static inline void tasklet_schedule(struct tasklet_struct *t) 335 { 336 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 337 __tasklet_schedule(t); 338 } 339 340 extern void FASTCALL(__tasklet_hi_schedule(struct tasklet_struct *t)); 341 342 static inline void tasklet_hi_schedule(struct tasklet_struct *t) 343 { 344 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 345 __tasklet_hi_schedule(t); 346 } 347 348 349 static inline void tasklet_disable_nosync(struct tasklet_struct *t) 350 { 351 atomic_inc(&t->count); 352 smp_mb__after_atomic_inc(); 353 } 354 355 static inline void tasklet_disable(struct tasklet_struct *t) 356 { 357 tasklet_disable_nosync(t); 358 tasklet_unlock_wait(t); 359 smp_mb(); 360 } 361 362 static inline void tasklet_enable(struct tasklet_struct *t) 363 { 364 smp_mb__before_atomic_dec(); 365 atomic_dec(&t->count); 366 } 367 368 static inline void tasklet_hi_enable(struct tasklet_struct *t) 369 { 370 smp_mb__before_atomic_dec(); 371 atomic_dec(&t->count); 372 } 373 374 extern void tasklet_kill(struct tasklet_struct *t); 375 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu); 376 extern void tasklet_init(struct tasklet_struct *t, 377 void (*func)(unsigned long), unsigned long data); 378 379 /* 380 * Autoprobing for irqs: 381 * 382 * probe_irq_on() and probe_irq_off() provide robust primitives 383 * for accurate IRQ probing during kernel initialization. They are 384 * reasonably simple to use, are not "fooled" by spurious interrupts, 385 * and, unlike other attempts at IRQ probing, they do not get hung on 386 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards). 387 * 388 * For reasonably foolproof probing, use them as follows: 389 * 390 * 1. clear and/or mask the device's internal interrupt. 391 * 2. sti(); 392 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs 393 * 4. enable the device and cause it to trigger an interrupt. 394 * 5. wait for the device to interrupt, using non-intrusive polling or a delay. 395 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple 396 * 7. service the device to clear its pending interrupt. 397 * 8. loop again if paranoia is required. 398 * 399 * probe_irq_on() returns a mask of allocated irq's. 400 * 401 * probe_irq_off() takes the mask as a parameter, 402 * and returns the irq number which occurred, 403 * or zero if none occurred, or a negative irq number 404 * if more than one irq occurred. 405 */ 406 407 #if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE) 408 static inline unsigned long probe_irq_on(void) 409 { 410 return 0; 411 } 412 static inline int probe_irq_off(unsigned long val) 413 { 414 return 0; 415 } 416 static inline unsigned int probe_irq_mask(unsigned long val) 417 { 418 return 0; 419 } 420 #else 421 extern unsigned long probe_irq_on(void); /* returns 0 on failure */ 422 extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */ 423 extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */ 424 #endif 425 426 #ifdef CONFIG_PROC_FS 427 /* Initialize /proc/irq/ */ 428 extern void init_irq_proc(void); 429 #else 430 static inline void init_irq_proc(void) 431 { 432 } 433 #endif 434 435 #endif 436