xref: /linux/kernel/irq/internals.h (revision 3f41368fbfe1b3d5922d317fe1a0a0cab6846802)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * IRQ subsystem internal functions and variables:
4  *
5  * Do not ever include this file from anything else than
6  * kernel/irq/. Do not even think about using any information outside
7  * of this file for your non core code.
8  */
9 #include <linux/irqdesc.h>
10 #include <linux/kernel_stat.h>
11 #include <linux/pm_runtime.h>
12 #include <linux/sched/clock.h>
13 
14 #ifdef CONFIG_SPARSE_IRQ
15 # define MAX_SPARSE_IRQS	INT_MAX
16 #else
17 # define MAX_SPARSE_IRQS	NR_IRQS
18 #endif
19 
20 #define istate core_internal_state__do_not_mess_with_it
21 
22 extern bool noirqdebug;
23 
24 extern struct irqaction chained_action;
25 
26 /*
27  * Bits used by threaded handlers:
28  * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run
29  * IRQTF_WARNED    - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed
30  * IRQTF_AFFINITY  - irq thread is requested to adjust affinity
31  * IRQTF_FORCED_THREAD  - irq action is force threaded
32  * IRQTF_READY     - signals that irq thread is ready
33  */
34 enum {
35 	IRQTF_RUNTHREAD,
36 	IRQTF_WARNED,
37 	IRQTF_AFFINITY,
38 	IRQTF_FORCED_THREAD,
39 	IRQTF_READY,
40 };
41 
42 /*
43  * Bit masks for desc->core_internal_state__do_not_mess_with_it
44  *
45  * IRQS_AUTODETECT		- autodetection in progress
46  * IRQS_SPURIOUS_DISABLED	- was disabled due to spurious interrupt
47  *				  detection
48  * IRQS_POLL_INPROGRESS		- polling in progress
49  * IRQS_ONESHOT			- irq is not unmasked in primary handler
50  * IRQS_REPLAY			- irq has been resent and will not be resent
51  * 				  again until the handler has run and cleared
52  * 				  this flag.
53  * IRQS_WAITING			- irq is waiting
54  * IRQS_PENDING			- irq needs to be resent and should be resent
55  * 				  at the next available opportunity.
56  * IRQS_SUSPENDED		- irq is suspended
57  * IRQS_NMI			- irq line is used to deliver NMIs
58  * IRQS_SYSFS			- descriptor has been added to sysfs
59  */
60 enum {
61 	IRQS_AUTODETECT		= 0x00000001,
62 	IRQS_SPURIOUS_DISABLED	= 0x00000002,
63 	IRQS_POLL_INPROGRESS	= 0x00000008,
64 	IRQS_ONESHOT		= 0x00000020,
65 	IRQS_REPLAY		= 0x00000040,
66 	IRQS_WAITING		= 0x00000080,
67 	IRQS_PENDING		= 0x00000200,
68 	IRQS_SUSPENDED		= 0x00000800,
69 	IRQS_TIMINGS		= 0x00001000,
70 	IRQS_NMI		= 0x00002000,
71 	IRQS_SYSFS		= 0x00004000,
72 };
73 
74 #include "debug.h"
75 #include "settings.h"
76 
77 extern int __irq_set_trigger(struct irq_desc *desc, unsigned long flags);
78 extern void __disable_irq(struct irq_desc *desc);
79 extern void __enable_irq(struct irq_desc *desc);
80 
81 #define IRQ_RESEND	true
82 #define IRQ_NORESEND	false
83 
84 #define IRQ_START_FORCE	true
85 #define IRQ_START_COND	false
86 
87 extern int irq_activate(struct irq_desc *desc);
88 extern int irq_activate_and_startup(struct irq_desc *desc, bool resend);
89 extern int irq_startup(struct irq_desc *desc, bool resend, bool force);
90 
91 extern void irq_shutdown(struct irq_desc *desc);
92 extern void irq_shutdown_and_deactivate(struct irq_desc *desc);
93 extern void irq_enable(struct irq_desc *desc);
94 extern void irq_disable(struct irq_desc *desc);
95 extern void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu);
96 extern void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu);
97 extern void mask_irq(struct irq_desc *desc);
98 extern void unmask_irq(struct irq_desc *desc);
99 extern void unmask_threaded_irq(struct irq_desc *desc);
100 
101 extern unsigned int kstat_irqs_desc(struct irq_desc *desc, const struct cpumask *cpumask);
102 
103 #ifdef CONFIG_SPARSE_IRQ
104 static inline void irq_mark_irq(unsigned int irq) { }
105 #else
106 extern void irq_mark_irq(unsigned int irq);
107 #endif
108 
109 extern int __irq_get_irqchip_state(struct irq_data *data,
110 				   enum irqchip_irq_state which,
111 				   bool *state);
112 
113 irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc);
114 irqreturn_t handle_irq_event_percpu(struct irq_desc *desc);
115 irqreturn_t handle_irq_event(struct irq_desc *desc);
116 
117 /* Resending of interrupts :*/
118 int check_irq_resend(struct irq_desc *desc, bool inject);
119 void clear_irq_resend(struct irq_desc *desc);
120 void irq_resend_init(struct irq_desc *desc);
121 bool irq_wait_for_poll(struct irq_desc *desc);
122 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
123 
124 void wake_threads_waitq(struct irq_desc *desc);
125 
126 #ifdef CONFIG_PROC_FS
127 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
128 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
129 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
130 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
131 #else
132 static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
133 static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { }
134 static inline void register_handler_proc(unsigned int irq,
135 					 struct irqaction *action) { }
136 static inline void unregister_handler_proc(unsigned int irq,
137 					   struct irqaction *action) { }
138 #endif
139 
140 extern bool irq_can_set_affinity_usr(unsigned int irq);
141 
142 extern void irq_set_thread_affinity(struct irq_desc *desc);
143 
144 extern int irq_do_set_affinity(struct irq_data *data,
145 			       const struct cpumask *dest, bool force);
146 
147 #ifdef CONFIG_SMP
148 extern int irq_setup_affinity(struct irq_desc *desc);
149 #else
150 static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }
151 #endif
152 
153 /* Inline functions for support of irq chips on slow busses */
154 static inline void chip_bus_lock(struct irq_desc *desc)
155 {
156 	if (unlikely(desc->irq_data.chip->irq_bus_lock))
157 		desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
158 }
159 
160 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
161 {
162 	if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
163 		desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
164 }
165 
166 #define _IRQ_DESC_CHECK		(1 << 0)
167 #define _IRQ_DESC_PERCPU	(1 << 1)
168 
169 #define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)
170 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
171 
172 #define for_each_action_of_desc(desc, act)			\
173 	for (act = desc->action; act; act = act->next)
174 
175 struct irq_desc *
176 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
177 		    unsigned int check);
178 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
179 
180 static inline struct irq_desc *
181 irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)
182 {
183 	return __irq_get_desc_lock(irq, flags, true, check);
184 }
185 
186 static inline void
187 irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags)
188 {
189 	__irq_put_desc_unlock(desc, flags, true);
190 }
191 
192 static inline struct irq_desc *
193 irq_get_desc_lock(unsigned int irq, unsigned long *flags, unsigned int check)
194 {
195 	return __irq_get_desc_lock(irq, flags, false, check);
196 }
197 
198 static inline void
199 irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags)
200 {
201 	__irq_put_desc_unlock(desc, flags, false);
202 }
203 
204 #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
205 
206 static inline unsigned int irqd_get(struct irq_data *d)
207 {
208 	return __irqd_to_state(d);
209 }
210 
211 /*
212  * Manipulation functions for irq_data.state
213  */
214 static inline void irqd_set_move_pending(struct irq_data *d)
215 {
216 	__irqd_to_state(d) |= IRQD_SETAFFINITY_PENDING;
217 }
218 
219 static inline void irqd_clr_move_pending(struct irq_data *d)
220 {
221 	__irqd_to_state(d) &= ~IRQD_SETAFFINITY_PENDING;
222 }
223 
224 static inline void irqd_set_managed_shutdown(struct irq_data *d)
225 {
226 	__irqd_to_state(d) |= IRQD_MANAGED_SHUTDOWN;
227 }
228 
229 static inline void irqd_clr_managed_shutdown(struct irq_data *d)
230 {
231 	__irqd_to_state(d) &= ~IRQD_MANAGED_SHUTDOWN;
232 }
233 
234 static inline void irqd_clear(struct irq_data *d, unsigned int mask)
235 {
236 	__irqd_to_state(d) &= ~mask;
237 }
238 
239 static inline void irqd_set(struct irq_data *d, unsigned int mask)
240 {
241 	__irqd_to_state(d) |= mask;
242 }
243 
244 static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
245 {
246 	return __irqd_to_state(d) & mask;
247 }
248 
249 static inline void irq_state_set_disabled(struct irq_desc *desc)
250 {
251 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
252 }
253 
254 static inline void irq_state_set_masked(struct irq_desc *desc)
255 {
256 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
257 }
258 
259 #undef __irqd_to_state
260 
261 static inline void __kstat_incr_irqs_this_cpu(struct irq_desc *desc)
262 {
263 	__this_cpu_inc(desc->kstat_irqs->cnt);
264 	__this_cpu_inc(kstat.irqs_sum);
265 }
266 
267 static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
268 {
269 	__kstat_incr_irqs_this_cpu(desc);
270 	desc->tot_count++;
271 }
272 
273 static inline int irq_desc_get_node(struct irq_desc *desc)
274 {
275 	return irq_common_data_get_node(&desc->irq_common_data);
276 }
277 
278 static inline int irq_desc_is_chained(struct irq_desc *desc)
279 {
280 	return (desc->action && desc->action == &chained_action);
281 }
282 
283 static inline bool irq_is_nmi(struct irq_desc *desc)
284 {
285 	return desc->istate & IRQS_NMI;
286 }
287 
288 #ifdef CONFIG_PM_SLEEP
289 bool irq_pm_check_wakeup(struct irq_desc *desc);
290 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
291 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
292 #else
293 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
294 static inline void
295 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
296 static inline void
297 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
298 #endif
299 
300 #ifdef CONFIG_IRQ_TIMINGS
301 
302 #define IRQ_TIMINGS_SHIFT	5
303 #define IRQ_TIMINGS_SIZE	(1 << IRQ_TIMINGS_SHIFT)
304 #define IRQ_TIMINGS_MASK	(IRQ_TIMINGS_SIZE - 1)
305 
306 /**
307  * struct irq_timings - irq timings storing structure
308  * @values: a circular buffer of u64 encoded <timestamp,irq> values
309  * @count: the number of elements in the array
310  */
311 struct irq_timings {
312 	u64	values[IRQ_TIMINGS_SIZE];
313 	int	count;
314 };
315 
316 DECLARE_PER_CPU(struct irq_timings, irq_timings);
317 
318 extern void irq_timings_free(int irq);
319 extern int irq_timings_alloc(int irq);
320 
321 static inline void irq_remove_timings(struct irq_desc *desc)
322 {
323 	desc->istate &= ~IRQS_TIMINGS;
324 
325 	irq_timings_free(irq_desc_get_irq(desc));
326 }
327 
328 static inline void irq_setup_timings(struct irq_desc *desc, struct irqaction *act)
329 {
330 	int irq = irq_desc_get_irq(desc);
331 	int ret;
332 
333 	/*
334 	 * We don't need the measurement because the idle code already
335 	 * knows the next expiry event.
336 	 */
337 	if (act->flags & __IRQF_TIMER)
338 		return;
339 
340 	/*
341 	 * In case the timing allocation fails, we just want to warn,
342 	 * not fail, so letting the system boot anyway.
343 	 */
344 	ret = irq_timings_alloc(irq);
345 	if (ret) {
346 		pr_warn("Failed to allocate irq timing stats for irq%d (%d)",
347 			irq, ret);
348 		return;
349 	}
350 
351 	desc->istate |= IRQS_TIMINGS;
352 }
353 
354 extern void irq_timings_enable(void);
355 extern void irq_timings_disable(void);
356 
357 DECLARE_STATIC_KEY_FALSE(irq_timing_enabled);
358 
359 /*
360  * The interrupt number and the timestamp are encoded into a single
361  * u64 variable to optimize the size.
362  * 48 bit time stamp and 16 bit IRQ number is way sufficient.
363  *  Who cares an IRQ after 78 hours of idle time?
364  */
365 static inline u64 irq_timing_encode(u64 timestamp, int irq)
366 {
367 	return (timestamp << 16) | irq;
368 }
369 
370 static inline int irq_timing_decode(u64 value, u64 *timestamp)
371 {
372 	*timestamp = value >> 16;
373 	return value & U16_MAX;
374 }
375 
376 static __always_inline void irq_timings_push(u64 ts, int irq)
377 {
378 	struct irq_timings *timings = this_cpu_ptr(&irq_timings);
379 
380 	timings->values[timings->count & IRQ_TIMINGS_MASK] =
381 		irq_timing_encode(ts, irq);
382 
383 	timings->count++;
384 }
385 
386 /*
387  * The function record_irq_time is only called in one place in the
388  * interrupts handler. We want this function always inline so the code
389  * inside is embedded in the function and the static key branching
390  * code can act at the higher level. Without the explicit
391  * __always_inline we can end up with a function call and a small
392  * overhead in the hotpath for nothing.
393  */
394 static __always_inline void record_irq_time(struct irq_desc *desc)
395 {
396 	if (!static_branch_likely(&irq_timing_enabled))
397 		return;
398 
399 	if (desc->istate & IRQS_TIMINGS)
400 		irq_timings_push(local_clock(), irq_desc_get_irq(desc));
401 }
402 #else
403 static inline void irq_remove_timings(struct irq_desc *desc) {}
404 static inline void irq_setup_timings(struct irq_desc *desc,
405 				     struct irqaction *act) {};
406 static inline void record_irq_time(struct irq_desc *desc) {}
407 #endif /* CONFIG_IRQ_TIMINGS */
408 
409 
410 #ifdef CONFIG_GENERIC_IRQ_CHIP
411 void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
412 			   int num_ct, unsigned int irq_base,
413 			   void __iomem *reg_base, irq_flow_handler_t handler);
414 #else
415 static inline void
416 irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
417 		      int num_ct, unsigned int irq_base,
418 		      void __iomem *reg_base, irq_flow_handler_t handler) { }
419 #endif /* CONFIG_GENERIC_IRQ_CHIP */
420 
421 #ifdef CONFIG_GENERIC_PENDING_IRQ
422 static inline bool irq_can_move_pcntxt(struct irq_data *data)
423 {
424 	return irqd_can_move_in_process_context(data);
425 }
426 static inline bool irq_move_pending(struct irq_data *data)
427 {
428 	return irqd_is_setaffinity_pending(data);
429 }
430 static inline void
431 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
432 {
433 	cpumask_copy(desc->pending_mask, mask);
434 }
435 static inline void
436 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
437 {
438 	cpumask_copy(mask, desc->pending_mask);
439 }
440 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
441 {
442 	return desc->pending_mask;
443 }
444 static inline bool handle_enforce_irqctx(struct irq_data *data)
445 {
446 	return irqd_is_handle_enforce_irqctx(data);
447 }
448 bool irq_fixup_move_pending(struct irq_desc *desc, bool force_clear);
449 #else /* CONFIG_GENERIC_PENDING_IRQ */
450 static inline bool irq_can_move_pcntxt(struct irq_data *data)
451 {
452 	return true;
453 }
454 static inline bool irq_move_pending(struct irq_data *data)
455 {
456 	return false;
457 }
458 static inline void
459 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
460 {
461 }
462 static inline void
463 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
464 {
465 }
466 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
467 {
468 	return NULL;
469 }
470 static inline bool irq_fixup_move_pending(struct irq_desc *desc, bool fclear)
471 {
472 	return false;
473 }
474 static inline bool handle_enforce_irqctx(struct irq_data *data)
475 {
476 	return false;
477 }
478 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
479 
480 #if !defined(CONFIG_IRQ_DOMAIN) || !defined(CONFIG_IRQ_DOMAIN_HIERARCHY)
481 static inline int irq_domain_activate_irq(struct irq_data *data, bool reserve)
482 {
483 	irqd_set_activated(data);
484 	return 0;
485 }
486 static inline void irq_domain_deactivate_irq(struct irq_data *data)
487 {
488 	irqd_clr_activated(data);
489 }
490 #endif
491 
492 static inline struct irq_data *irqd_get_parent_data(struct irq_data *irqd)
493 {
494 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
495 	return irqd->parent_data;
496 #else
497 	return NULL;
498 #endif
499 }
500 
501 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
502 #include <linux/debugfs.h>
503 
504 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc);
505 static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
506 {
507 	debugfs_remove(desc->debugfs_file);
508 	kfree(desc->dev_name);
509 }
510 void irq_debugfs_copy_devname(int irq, struct device *dev);
511 # ifdef CONFIG_IRQ_DOMAIN
512 void irq_domain_debugfs_init(struct dentry *root);
513 # else
514 static inline void irq_domain_debugfs_init(struct dentry *root)
515 {
516 }
517 # endif
518 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
519 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)
520 {
521 }
522 static inline void irq_remove_debugfs_entry(struct irq_desc *d)
523 {
524 }
525 static inline void irq_debugfs_copy_devname(int irq, struct device *dev)
526 {
527 }
528 #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
529