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