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