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