xref: /linux/kernel/irq/internals.h (revision 41e0d49104dbff888ef6446ea46842fde66c0a76)
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 IRQ_BITMAP_BITS	(NR_IRQS + 8196)
16 #else
17 # define IRQ_BITMAP_BITS	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 is replayed
51  * IRQS_WAITING			- irq is waiting
52  * IRQS_PENDING			- irq is pending and replayed later
53  * IRQS_SUSPENDED		- irq is suspended
54  * IRQS_NMI			- irq line is used to deliver NMIs
55  * IRQS_SYSFS			- descriptor has been added to sysfs
56  */
57 enum {
58 	IRQS_AUTODETECT		= 0x00000001,
59 	IRQS_SPURIOUS_DISABLED	= 0x00000002,
60 	IRQS_POLL_INPROGRESS	= 0x00000008,
61 	IRQS_ONESHOT		= 0x00000020,
62 	IRQS_REPLAY		= 0x00000040,
63 	IRQS_WAITING		= 0x00000080,
64 	IRQS_PENDING		= 0x00000200,
65 	IRQS_SUSPENDED		= 0x00000800,
66 	IRQS_TIMINGS		= 0x00001000,
67 	IRQS_NMI		= 0x00002000,
68 	IRQS_SYSFS		= 0x00004000,
69 };
70 
71 #include "debug.h"
72 #include "settings.h"
73 
74 extern int __irq_set_trigger(struct irq_desc *desc, unsigned long flags);
75 extern void __disable_irq(struct irq_desc *desc);
76 extern void __enable_irq(struct irq_desc *desc);
77 
78 #define IRQ_RESEND	true
79 #define IRQ_NORESEND	false
80 
81 #define IRQ_START_FORCE	true
82 #define IRQ_START_COND	false
83 
84 extern int irq_activate(struct irq_desc *desc);
85 extern int irq_activate_and_startup(struct irq_desc *desc, bool resend);
86 extern int irq_startup(struct irq_desc *desc, bool resend, bool force);
87 
88 extern void irq_shutdown(struct irq_desc *desc);
89 extern void irq_shutdown_and_deactivate(struct irq_desc *desc);
90 extern void irq_enable(struct irq_desc *desc);
91 extern void irq_disable(struct irq_desc *desc);
92 extern void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu);
93 extern void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu);
94 extern void mask_irq(struct irq_desc *desc);
95 extern void unmask_irq(struct irq_desc *desc);
96 extern void unmask_threaded_irq(struct irq_desc *desc);
97 
98 #ifdef CONFIG_SPARSE_IRQ
99 static inline void irq_mark_irq(unsigned int irq) { }
100 #else
101 extern void irq_mark_irq(unsigned int irq);
102 #endif
103 
104 extern int __irq_get_irqchip_state(struct irq_data *data,
105 				   enum irqchip_irq_state which,
106 				   bool *state);
107 
108 extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr);
109 
110 irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc);
111 irqreturn_t handle_irq_event_percpu(struct irq_desc *desc);
112 irqreturn_t handle_irq_event(struct irq_desc *desc);
113 
114 /* Resending of interrupts :*/
115 int check_irq_resend(struct irq_desc *desc, bool inject);
116 bool irq_wait_for_poll(struct irq_desc *desc);
117 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
118 
119 #ifdef CONFIG_PROC_FS
120 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
121 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
122 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
123 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
124 #else
125 static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
126 static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { }
127 static inline void register_handler_proc(unsigned int irq,
128 					 struct irqaction *action) { }
129 static inline void unregister_handler_proc(unsigned int irq,
130 					   struct irqaction *action) { }
131 #endif
132 
133 extern bool irq_can_set_affinity_usr(unsigned int irq);
134 
135 extern void irq_set_thread_affinity(struct irq_desc *desc);
136 
137 extern int irq_do_set_affinity(struct irq_data *data,
138 			       const struct cpumask *dest, bool force);
139 
140 #ifdef CONFIG_SMP
141 extern int irq_setup_affinity(struct irq_desc *desc);
142 #else
143 static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }
144 #endif
145 
146 /* Inline functions for support of irq chips on slow busses */
147 static inline void chip_bus_lock(struct irq_desc *desc)
148 {
149 	if (unlikely(desc->irq_data.chip->irq_bus_lock))
150 		desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
151 }
152 
153 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
154 {
155 	if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
156 		desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
157 }
158 
159 #define _IRQ_DESC_CHECK		(1 << 0)
160 #define _IRQ_DESC_PERCPU	(1 << 1)
161 
162 #define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)
163 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
164 
165 #define for_each_action_of_desc(desc, act)			\
166 	for (act = desc->action; act; act = act->next)
167 
168 struct irq_desc *
169 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
170 		    unsigned int check);
171 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
172 
173 static inline struct irq_desc *
174 irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)
175 {
176 	return __irq_get_desc_lock(irq, flags, true, check);
177 }
178 
179 static inline void
180 irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags)
181 {
182 	__irq_put_desc_unlock(desc, flags, true);
183 }
184 
185 static inline struct irq_desc *
186 irq_get_desc_lock(unsigned int irq, unsigned long *flags, unsigned int check)
187 {
188 	return __irq_get_desc_lock(irq, flags, false, check);
189 }
190 
191 static inline void
192 irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags)
193 {
194 	__irq_put_desc_unlock(desc, flags, false);
195 }
196 
197 #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
198 
199 static inline unsigned int irqd_get(struct irq_data *d)
200 {
201 	return __irqd_to_state(d);
202 }
203 
204 /*
205  * Manipulation functions for irq_data.state
206  */
207 static inline void irqd_set_move_pending(struct irq_data *d)
208 {
209 	__irqd_to_state(d) |= IRQD_SETAFFINITY_PENDING;
210 }
211 
212 static inline void irqd_clr_move_pending(struct irq_data *d)
213 {
214 	__irqd_to_state(d) &= ~IRQD_SETAFFINITY_PENDING;
215 }
216 
217 static inline void irqd_set_managed_shutdown(struct irq_data *d)
218 {
219 	__irqd_to_state(d) |= IRQD_MANAGED_SHUTDOWN;
220 }
221 
222 static inline void irqd_clr_managed_shutdown(struct irq_data *d)
223 {
224 	__irqd_to_state(d) &= ~IRQD_MANAGED_SHUTDOWN;
225 }
226 
227 static inline void irqd_clear(struct irq_data *d, unsigned int mask)
228 {
229 	__irqd_to_state(d) &= ~mask;
230 }
231 
232 static inline void irqd_set(struct irq_data *d, unsigned int mask)
233 {
234 	__irqd_to_state(d) |= mask;
235 }
236 
237 static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
238 {
239 	return __irqd_to_state(d) & mask;
240 }
241 
242 static inline void irq_state_set_disabled(struct irq_desc *desc)
243 {
244 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
245 }
246 
247 static inline void irq_state_set_masked(struct irq_desc *desc)
248 {
249 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
250 }
251 
252 #undef __irqd_to_state
253 
254 static inline void __kstat_incr_irqs_this_cpu(struct irq_desc *desc)
255 {
256 	__this_cpu_inc(*desc->kstat_irqs);
257 	__this_cpu_inc(kstat.irqs_sum);
258 }
259 
260 static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
261 {
262 	__kstat_incr_irqs_this_cpu(desc);
263 	desc->tot_count++;
264 }
265 
266 static inline int irq_desc_get_node(struct irq_desc *desc)
267 {
268 	return irq_common_data_get_node(&desc->irq_common_data);
269 }
270 
271 static inline int irq_desc_is_chained(struct irq_desc *desc)
272 {
273 	return (desc->action && desc->action == &chained_action);
274 }
275 
276 #ifdef CONFIG_PM_SLEEP
277 bool irq_pm_check_wakeup(struct irq_desc *desc);
278 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
279 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
280 #else
281 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
282 static inline void
283 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
284 static inline void
285 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
286 #endif
287 
288 #ifdef CONFIG_IRQ_TIMINGS
289 
290 #define IRQ_TIMINGS_SHIFT	5
291 #define IRQ_TIMINGS_SIZE	(1 << IRQ_TIMINGS_SHIFT)
292 #define IRQ_TIMINGS_MASK	(IRQ_TIMINGS_SIZE - 1)
293 
294 /**
295  * struct irq_timings - irq timings storing structure
296  * @values: a circular buffer of u64 encoded <timestamp,irq> values
297  * @count: the number of elements in the array
298  */
299 struct irq_timings {
300 	u64	values[IRQ_TIMINGS_SIZE];
301 	int	count;
302 };
303 
304 DECLARE_PER_CPU(struct irq_timings, irq_timings);
305 
306 extern void irq_timings_free(int irq);
307 extern int irq_timings_alloc(int irq);
308 
309 static inline void irq_remove_timings(struct irq_desc *desc)
310 {
311 	desc->istate &= ~IRQS_TIMINGS;
312 
313 	irq_timings_free(irq_desc_get_irq(desc));
314 }
315 
316 static inline void irq_setup_timings(struct irq_desc *desc, struct irqaction *act)
317 {
318 	int irq = irq_desc_get_irq(desc);
319 	int ret;
320 
321 	/*
322 	 * We don't need the measurement because the idle code already
323 	 * knows the next expiry event.
324 	 */
325 	if (act->flags & __IRQF_TIMER)
326 		return;
327 
328 	/*
329 	 * In case the timing allocation fails, we just want to warn,
330 	 * not fail, so letting the system boot anyway.
331 	 */
332 	ret = irq_timings_alloc(irq);
333 	if (ret) {
334 		pr_warn("Failed to allocate irq timing stats for irq%d (%d)",
335 			irq, ret);
336 		return;
337 	}
338 
339 	desc->istate |= IRQS_TIMINGS;
340 }
341 
342 extern void irq_timings_enable(void);
343 extern void irq_timings_disable(void);
344 
345 DECLARE_STATIC_KEY_FALSE(irq_timing_enabled);
346 
347 /*
348  * The interrupt number and the timestamp are encoded into a single
349  * u64 variable to optimize the size.
350  * 48 bit time stamp and 16 bit IRQ number is way sufficient.
351  *  Who cares an IRQ after 78 hours of idle time?
352  */
353 static inline u64 irq_timing_encode(u64 timestamp, int irq)
354 {
355 	return (timestamp << 16) | irq;
356 }
357 
358 static inline int irq_timing_decode(u64 value, u64 *timestamp)
359 {
360 	*timestamp = value >> 16;
361 	return value & U16_MAX;
362 }
363 
364 static __always_inline void irq_timings_push(u64 ts, int irq)
365 {
366 	struct irq_timings *timings = this_cpu_ptr(&irq_timings);
367 
368 	timings->values[timings->count & IRQ_TIMINGS_MASK] =
369 		irq_timing_encode(ts, irq);
370 
371 	timings->count++;
372 }
373 
374 /*
375  * The function record_irq_time is only called in one place in the
376  * interrupts handler. We want this function always inline so the code
377  * inside is embedded in the function and the static key branching
378  * code can act at the higher level. Without the explicit
379  * __always_inline we can end up with a function call and a small
380  * overhead in the hotpath for nothing.
381  */
382 static __always_inline void record_irq_time(struct irq_desc *desc)
383 {
384 	if (!static_branch_likely(&irq_timing_enabled))
385 		return;
386 
387 	if (desc->istate & IRQS_TIMINGS)
388 		irq_timings_push(local_clock(), irq_desc_get_irq(desc));
389 }
390 #else
391 static inline void irq_remove_timings(struct irq_desc *desc) {}
392 static inline void irq_setup_timings(struct irq_desc *desc,
393 				     struct irqaction *act) {};
394 static inline void record_irq_time(struct irq_desc *desc) {}
395 #endif /* CONFIG_IRQ_TIMINGS */
396 
397 
398 #ifdef CONFIG_GENERIC_IRQ_CHIP
399 void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
400 			   int num_ct, unsigned int irq_base,
401 			   void __iomem *reg_base, irq_flow_handler_t handler);
402 #else
403 static inline void
404 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 #endif /* CONFIG_GENERIC_IRQ_CHIP */
408 
409 #ifdef CONFIG_GENERIC_PENDING_IRQ
410 static inline bool irq_can_move_pcntxt(struct irq_data *data)
411 {
412 	return irqd_can_move_in_process_context(data);
413 }
414 static inline bool irq_move_pending(struct irq_data *data)
415 {
416 	return irqd_is_setaffinity_pending(data);
417 }
418 static inline void
419 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
420 {
421 	cpumask_copy(desc->pending_mask, mask);
422 }
423 static inline void
424 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
425 {
426 	cpumask_copy(mask, desc->pending_mask);
427 }
428 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
429 {
430 	return desc->pending_mask;
431 }
432 static inline bool handle_enforce_irqctx(struct irq_data *data)
433 {
434 	return irqd_is_handle_enforce_irqctx(data);
435 }
436 bool irq_fixup_move_pending(struct irq_desc *desc, bool force_clear);
437 #else /* CONFIG_GENERIC_PENDING_IRQ */
438 static inline bool irq_can_move_pcntxt(struct irq_data *data)
439 {
440 	return true;
441 }
442 static inline bool irq_move_pending(struct irq_data *data)
443 {
444 	return false;
445 }
446 static inline void
447 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
448 {
449 }
450 static inline void
451 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
452 {
453 }
454 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
455 {
456 	return NULL;
457 }
458 static inline bool irq_fixup_move_pending(struct irq_desc *desc, bool fclear)
459 {
460 	return false;
461 }
462 static inline bool handle_enforce_irqctx(struct irq_data *data)
463 {
464 	return false;
465 }
466 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
467 
468 #if !defined(CONFIG_IRQ_DOMAIN) || !defined(CONFIG_IRQ_DOMAIN_HIERARCHY)
469 static inline int irq_domain_activate_irq(struct irq_data *data, bool reserve)
470 {
471 	irqd_set_activated(data);
472 	return 0;
473 }
474 static inline void irq_domain_deactivate_irq(struct irq_data *data)
475 {
476 	irqd_clr_activated(data);
477 }
478 #endif
479 
480 static inline struct irq_data *irqd_get_parent_data(struct irq_data *irqd)
481 {
482 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
483 	return irqd->parent_data;
484 #else
485 	return NULL;
486 #endif
487 }
488 
489 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
490 #include <linux/debugfs.h>
491 
492 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc);
493 static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
494 {
495 	debugfs_remove(desc->debugfs_file);
496 	kfree(desc->dev_name);
497 }
498 void irq_debugfs_copy_devname(int irq, struct device *dev);
499 # ifdef CONFIG_IRQ_DOMAIN
500 void irq_domain_debugfs_init(struct dentry *root);
501 # else
502 static inline void irq_domain_debugfs_init(struct dentry *root)
503 {
504 }
505 # endif
506 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
507 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)
508 {
509 }
510 static inline void irq_remove_debugfs_entry(struct irq_desc *d)
511 {
512 }
513 static inline void irq_debugfs_copy_devname(int irq, struct device *dev)
514 {
515 }
516 #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
517