xref: /linux/kernel/irq/internals.h (revision b8e85e6f3a09fc56b0ff574887798962ef8a8f80)
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 #ifdef CONFIG_SPARSE_IRQ
102 static inline void irq_mark_irq(unsigned int irq) { }
103 #else
104 extern void irq_mark_irq(unsigned int irq);
105 #endif
106 
107 extern int __irq_get_irqchip_state(struct irq_data *data,
108 				   enum irqchip_irq_state which,
109 				   bool *state);
110 
111 irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc);
112 irqreturn_t handle_irq_event_percpu(struct irq_desc *desc);
113 irqreturn_t handle_irq_event(struct irq_desc *desc);
114 
115 /* Resending of interrupts :*/
116 int check_irq_resend(struct irq_desc *desc, bool inject);
117 void clear_irq_resend(struct irq_desc *desc);
118 void irq_resend_init(struct irq_desc *desc);
119 bool irq_wait_for_poll(struct irq_desc *desc);
120 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
121 
122 void wake_threads_waitq(struct irq_desc *desc);
123 
124 #ifdef CONFIG_PROC_FS
125 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
126 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
127 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
128 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
129 #else
130 static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
131 static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { }
132 static inline void register_handler_proc(unsigned int irq,
133 					 struct irqaction *action) { }
134 static inline void unregister_handler_proc(unsigned int irq,
135 					   struct irqaction *action) { }
136 #endif
137 
138 extern bool irq_can_set_affinity_usr(unsigned int irq);
139 
140 extern void irq_set_thread_affinity(struct irq_desc *desc);
141 
142 extern int irq_do_set_affinity(struct irq_data *data,
143 			       const struct cpumask *dest, bool force);
144 
145 #ifdef CONFIG_SMP
146 extern int irq_setup_affinity(struct irq_desc *desc);
147 #else
148 static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }
149 #endif
150 
151 /* Inline functions for support of irq chips on slow busses */
152 static inline void chip_bus_lock(struct irq_desc *desc)
153 {
154 	if (unlikely(desc->irq_data.chip->irq_bus_lock))
155 		desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
156 }
157 
158 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
159 {
160 	if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
161 		desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
162 }
163 
164 #define _IRQ_DESC_CHECK		(1 << 0)
165 #define _IRQ_DESC_PERCPU	(1 << 1)
166 
167 #define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)
168 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
169 
170 #define for_each_action_of_desc(desc, act)			\
171 	for (act = desc->action; act; act = act->next)
172 
173 struct irq_desc *
174 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
175 		    unsigned int check);
176 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
177 
178 static inline struct irq_desc *
179 irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)
180 {
181 	return __irq_get_desc_lock(irq, flags, true, check);
182 }
183 
184 static inline void
185 irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags)
186 {
187 	__irq_put_desc_unlock(desc, flags, true);
188 }
189 
190 static inline struct irq_desc *
191 irq_get_desc_lock(unsigned int irq, unsigned long *flags, unsigned int check)
192 {
193 	return __irq_get_desc_lock(irq, flags, false, check);
194 }
195 
196 static inline void
197 irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags)
198 {
199 	__irq_put_desc_unlock(desc, flags, false);
200 }
201 
202 #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
203 
204 static inline unsigned int irqd_get(struct irq_data *d)
205 {
206 	return __irqd_to_state(d);
207 }
208 
209 /*
210  * Manipulation functions for irq_data.state
211  */
212 static inline void irqd_set_move_pending(struct irq_data *d)
213 {
214 	__irqd_to_state(d) |= IRQD_SETAFFINITY_PENDING;
215 }
216 
217 static inline void irqd_clr_move_pending(struct irq_data *d)
218 {
219 	__irqd_to_state(d) &= ~IRQD_SETAFFINITY_PENDING;
220 }
221 
222 static inline void irqd_set_managed_shutdown(struct irq_data *d)
223 {
224 	__irqd_to_state(d) |= IRQD_MANAGED_SHUTDOWN;
225 }
226 
227 static inline void irqd_clr_managed_shutdown(struct irq_data *d)
228 {
229 	__irqd_to_state(d) &= ~IRQD_MANAGED_SHUTDOWN;
230 }
231 
232 static inline void irqd_clear(struct irq_data *d, unsigned int mask)
233 {
234 	__irqd_to_state(d) &= ~mask;
235 }
236 
237 static inline void irqd_set(struct irq_data *d, unsigned int mask)
238 {
239 	__irqd_to_state(d) |= mask;
240 }
241 
242 static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
243 {
244 	return __irqd_to_state(d) & mask;
245 }
246 
247 static inline void irq_state_set_disabled(struct irq_desc *desc)
248 {
249 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
250 }
251 
252 static inline void irq_state_set_masked(struct irq_desc *desc)
253 {
254 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
255 }
256 
257 #undef __irqd_to_state
258 
259 static inline void __kstat_incr_irqs_this_cpu(struct irq_desc *desc)
260 {
261 	__this_cpu_inc(*desc->kstat_irqs);
262 	__this_cpu_inc(kstat.irqs_sum);
263 }
264 
265 static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
266 {
267 	__kstat_incr_irqs_this_cpu(desc);
268 	desc->tot_count++;
269 }
270 
271 static inline int irq_desc_get_node(struct irq_desc *desc)
272 {
273 	return irq_common_data_get_node(&desc->irq_common_data);
274 }
275 
276 static inline int irq_desc_is_chained(struct irq_desc *desc)
277 {
278 	return (desc->action && desc->action == &chained_action);
279 }
280 
281 #ifdef CONFIG_PM_SLEEP
282 bool irq_pm_check_wakeup(struct irq_desc *desc);
283 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
284 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
285 #else
286 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
287 static inline void
288 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
289 static inline void
290 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
291 #endif
292 
293 #ifdef CONFIG_IRQ_TIMINGS
294 
295 #define IRQ_TIMINGS_SHIFT	5
296 #define IRQ_TIMINGS_SIZE	(1 << IRQ_TIMINGS_SHIFT)
297 #define IRQ_TIMINGS_MASK	(IRQ_TIMINGS_SIZE - 1)
298 
299 /**
300  * struct irq_timings - irq timings storing structure
301  * @values: a circular buffer of u64 encoded <timestamp,irq> values
302  * @count: the number of elements in the array
303  */
304 struct irq_timings {
305 	u64	values[IRQ_TIMINGS_SIZE];
306 	int	count;
307 };
308 
309 DECLARE_PER_CPU(struct irq_timings, irq_timings);
310 
311 extern void irq_timings_free(int irq);
312 extern int irq_timings_alloc(int irq);
313 
314 static inline void irq_remove_timings(struct irq_desc *desc)
315 {
316 	desc->istate &= ~IRQS_TIMINGS;
317 
318 	irq_timings_free(irq_desc_get_irq(desc));
319 }
320 
321 static inline void irq_setup_timings(struct irq_desc *desc, struct irqaction *act)
322 {
323 	int irq = irq_desc_get_irq(desc);
324 	int ret;
325 
326 	/*
327 	 * We don't need the measurement because the idle code already
328 	 * knows the next expiry event.
329 	 */
330 	if (act->flags & __IRQF_TIMER)
331 		return;
332 
333 	/*
334 	 * In case the timing allocation fails, we just want to warn,
335 	 * not fail, so letting the system boot anyway.
336 	 */
337 	ret = irq_timings_alloc(irq);
338 	if (ret) {
339 		pr_warn("Failed to allocate irq timing stats for irq%d (%d)",
340 			irq, ret);
341 		return;
342 	}
343 
344 	desc->istate |= IRQS_TIMINGS;
345 }
346 
347 extern void irq_timings_enable(void);
348 extern void irq_timings_disable(void);
349 
350 DECLARE_STATIC_KEY_FALSE(irq_timing_enabled);
351 
352 /*
353  * The interrupt number and the timestamp are encoded into a single
354  * u64 variable to optimize the size.
355  * 48 bit time stamp and 16 bit IRQ number is way sufficient.
356  *  Who cares an IRQ after 78 hours of idle time?
357  */
358 static inline u64 irq_timing_encode(u64 timestamp, int irq)
359 {
360 	return (timestamp << 16) | irq;
361 }
362 
363 static inline int irq_timing_decode(u64 value, u64 *timestamp)
364 {
365 	*timestamp = value >> 16;
366 	return value & U16_MAX;
367 }
368 
369 static __always_inline void irq_timings_push(u64 ts, int irq)
370 {
371 	struct irq_timings *timings = this_cpu_ptr(&irq_timings);
372 
373 	timings->values[timings->count & IRQ_TIMINGS_MASK] =
374 		irq_timing_encode(ts, irq);
375 
376 	timings->count++;
377 }
378 
379 /*
380  * The function record_irq_time is only called in one place in the
381  * interrupts handler. We want this function always inline so the code
382  * inside is embedded in the function and the static key branching
383  * code can act at the higher level. Without the explicit
384  * __always_inline we can end up with a function call and a small
385  * overhead in the hotpath for nothing.
386  */
387 static __always_inline void record_irq_time(struct irq_desc *desc)
388 {
389 	if (!static_branch_likely(&irq_timing_enabled))
390 		return;
391 
392 	if (desc->istate & IRQS_TIMINGS)
393 		irq_timings_push(local_clock(), irq_desc_get_irq(desc));
394 }
395 #else
396 static inline void irq_remove_timings(struct irq_desc *desc) {}
397 static inline void irq_setup_timings(struct irq_desc *desc,
398 				     struct irqaction *act) {};
399 static inline void record_irq_time(struct irq_desc *desc) {}
400 #endif /* CONFIG_IRQ_TIMINGS */
401 
402 
403 #ifdef CONFIG_GENERIC_IRQ_CHIP
404 void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
405 			   int num_ct, unsigned int irq_base,
406 			   void __iomem *reg_base, irq_flow_handler_t handler);
407 #else
408 static inline void
409 irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
410 		      int num_ct, unsigned int irq_base,
411 		      void __iomem *reg_base, irq_flow_handler_t handler) { }
412 #endif /* CONFIG_GENERIC_IRQ_CHIP */
413 
414 #ifdef CONFIG_GENERIC_PENDING_IRQ
415 static inline bool irq_can_move_pcntxt(struct irq_data *data)
416 {
417 	return irqd_can_move_in_process_context(data);
418 }
419 static inline bool irq_move_pending(struct irq_data *data)
420 {
421 	return irqd_is_setaffinity_pending(data);
422 }
423 static inline void
424 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
425 {
426 	cpumask_copy(desc->pending_mask, mask);
427 }
428 static inline void
429 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
430 {
431 	cpumask_copy(mask, desc->pending_mask);
432 }
433 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
434 {
435 	return desc->pending_mask;
436 }
437 static inline bool handle_enforce_irqctx(struct irq_data *data)
438 {
439 	return irqd_is_handle_enforce_irqctx(data);
440 }
441 bool irq_fixup_move_pending(struct irq_desc *desc, bool force_clear);
442 #else /* CONFIG_GENERIC_PENDING_IRQ */
443 static inline bool irq_can_move_pcntxt(struct irq_data *data)
444 {
445 	return true;
446 }
447 static inline bool irq_move_pending(struct irq_data *data)
448 {
449 	return false;
450 }
451 static inline void
452 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
453 {
454 }
455 static inline void
456 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
457 {
458 }
459 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
460 {
461 	return NULL;
462 }
463 static inline bool irq_fixup_move_pending(struct irq_desc *desc, bool fclear)
464 {
465 	return false;
466 }
467 static inline bool handle_enforce_irqctx(struct irq_data *data)
468 {
469 	return false;
470 }
471 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
472 
473 #if !defined(CONFIG_IRQ_DOMAIN) || !defined(CONFIG_IRQ_DOMAIN_HIERARCHY)
474 static inline int irq_domain_activate_irq(struct irq_data *data, bool reserve)
475 {
476 	irqd_set_activated(data);
477 	return 0;
478 }
479 static inline void irq_domain_deactivate_irq(struct irq_data *data)
480 {
481 	irqd_clr_activated(data);
482 }
483 #endif
484 
485 static inline struct irq_data *irqd_get_parent_data(struct irq_data *irqd)
486 {
487 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
488 	return irqd->parent_data;
489 #else
490 	return NULL;
491 #endif
492 }
493 
494 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
495 #include <linux/debugfs.h>
496 
497 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc);
498 static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
499 {
500 	debugfs_remove(desc->debugfs_file);
501 	kfree(desc->dev_name);
502 }
503 void irq_debugfs_copy_devname(int irq, struct device *dev);
504 # ifdef CONFIG_IRQ_DOMAIN
505 void irq_domain_debugfs_init(struct dentry *root);
506 # else
507 static inline void irq_domain_debugfs_init(struct dentry *root)
508 {
509 }
510 # endif
511 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
512 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)
513 {
514 }
515 static inline void irq_remove_debugfs_entry(struct irq_desc *d)
516 {
517 }
518 static inline void irq_debugfs_copy_devname(int irq, struct device *dev)
519 {
520 }
521 #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
522