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 extern void irq_startup_managed(struct irq_desc *desc);
91 
92 extern void irq_shutdown(struct irq_desc *desc);
93 extern void irq_shutdown_and_deactivate(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 irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc);
108 irqreturn_t handle_irq_event_percpu(struct irq_desc *desc);
109 irqreturn_t handle_irq_event(struct irq_desc *desc);
110 
111 /* Resending of interrupts :*/
112 int check_irq_resend(struct irq_desc *desc, bool inject);
113 void clear_irq_resend(struct irq_desc *desc);
114 void irq_resend_init(struct irq_desc *desc);
115 bool irq_wait_for_poll(struct irq_desc *desc);
116 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
117 
118 void wake_threads_waitq(struct irq_desc *desc);
119 
120 #ifdef CONFIG_PROC_FS
121 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
122 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
123 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
124 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
125 #else
126 static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
127 static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { }
128 static inline void register_handler_proc(unsigned int irq,
129 					 struct irqaction *action) { }
130 static inline void unregister_handler_proc(unsigned int irq,
131 					   struct irqaction *action) { }
132 #endif
133 
134 extern bool irq_can_set_affinity_usr(unsigned int irq);
135 
136 extern int irq_do_set_affinity(struct irq_data *data,
137 			       const struct cpumask *dest, bool force);
138 
139 #ifdef CONFIG_SMP
140 extern int irq_setup_affinity(struct irq_desc *desc);
141 #else
142 static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }
143 #endif
144 
145 
146 #define for_each_action_of_desc(desc, act)			\
147 	for (act = desc->action; act; act = act->next)
148 
149 /* Inline functions for support of irq chips on slow busses */
150 static inline void chip_bus_lock(struct irq_desc *desc)
151 {
152 	if (unlikely(desc->irq_data.chip->irq_bus_lock))
153 		desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
154 }
155 
156 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
157 {
158 	if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
159 		desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
160 }
161 
162 #define _IRQ_DESC_CHECK		(1 << 0)
163 #define _IRQ_DESC_PERCPU	(1 << 1)
164 
165 #define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)
166 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
167 
168 struct irq_desc *__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
169 				     unsigned int check);
170 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
171 
172 __DEFINE_CLASS_IS_CONDITIONAL(irqdesc_lock, true);
173 __DEFINE_UNLOCK_GUARD(irqdesc_lock, struct irq_desc,
174 		      __irq_put_desc_unlock(_T->lock, _T->flags, _T->bus),
175 		      unsigned long flags; bool bus);
176 
177 static inline class_irqdesc_lock_t class_irqdesc_lock_constructor(unsigned int irq, bool bus,
178 								  unsigned int check)
179 {
180 	class_irqdesc_lock_t _t = { .bus = bus, };
181 
182 	_t.lock = __irq_get_desc_lock(irq, &_t.flags, bus, check);
183 
184 	return _t;
185 }
186 
187 #define scoped_irqdesc_get_and_lock(_irq, _check)		\
188 	scoped_guard(irqdesc_lock, _irq, false, _check)
189 
190 #define scoped_irqdesc_get_and_buslock(_irq, _check)		\
191 	scoped_guard(irqdesc_lock, _irq, true, _check)
192 
193 #define scoped_irqdesc		((struct irq_desc *)(__guard_ptr(irqdesc_lock)(&scope)))
194 
195 #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
196 
197 static inline unsigned int irqd_get(struct irq_data *d)
198 {
199 	return __irqd_to_state(d);
200 }
201 
202 /*
203  * Manipulation functions for irq_data.state
204  */
205 static inline void irqd_set_move_pending(struct irq_data *d)
206 {
207 	__irqd_to_state(d) |= IRQD_SETAFFINITY_PENDING;
208 }
209 
210 static inline void irqd_clr_move_pending(struct irq_data *d)
211 {
212 	__irqd_to_state(d) &= ~IRQD_SETAFFINITY_PENDING;
213 }
214 
215 static inline void irqd_set_managed_shutdown(struct irq_data *d)
216 {
217 	__irqd_to_state(d) |= IRQD_MANAGED_SHUTDOWN;
218 }
219 
220 static inline void irqd_clr_managed_shutdown(struct irq_data *d)
221 {
222 	__irqd_to_state(d) &= ~IRQD_MANAGED_SHUTDOWN;
223 }
224 
225 static inline void irqd_clear(struct irq_data *d, unsigned int mask)
226 {
227 	__irqd_to_state(d) &= ~mask;
228 }
229 
230 static inline void irqd_set(struct irq_data *d, unsigned int mask)
231 {
232 	__irqd_to_state(d) |= mask;
233 }
234 
235 static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
236 {
237 	return __irqd_to_state(d) & mask;
238 }
239 
240 static inline void irq_state_set_disabled(struct irq_desc *desc)
241 {
242 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
243 }
244 
245 static inline void irq_state_set_masked(struct irq_desc *desc)
246 {
247 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
248 }
249 
250 #undef __irqd_to_state
251 
252 static inline void __kstat_incr_irqs_this_cpu(struct irq_desc *desc)
253 {
254 	__this_cpu_inc(desc->kstat_irqs->cnt);
255 	__this_cpu_inc(kstat.irqs_sum);
256 }
257 
258 static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
259 {
260 	__kstat_incr_irqs_this_cpu(desc);
261 	desc->tot_count++;
262 }
263 
264 static inline int irq_desc_get_node(struct irq_desc *desc)
265 {
266 	return irq_common_data_get_node(&desc->irq_common_data);
267 }
268 
269 static inline int irq_desc_is_chained(struct irq_desc *desc)
270 {
271 	return (desc->action && desc->action == &chained_action);
272 }
273 
274 static inline bool irq_is_nmi(struct irq_desc *desc)
275 {
276 	return desc->istate & IRQS_NMI;
277 }
278 
279 #ifdef CONFIG_PM_SLEEP
280 bool irq_pm_check_wakeup(struct irq_desc *desc);
281 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
282 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
283 #else
284 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
285 static inline void
286 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
287 static inline void
288 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
289 #endif
290 
291 #ifdef CONFIG_IRQ_TIMINGS
292 
293 #define IRQ_TIMINGS_SHIFT	5
294 #define IRQ_TIMINGS_SIZE	(1 << IRQ_TIMINGS_SHIFT)
295 #define IRQ_TIMINGS_MASK	(IRQ_TIMINGS_SIZE - 1)
296 
297 /**
298  * struct irq_timings - irq timings storing structure
299  * @values: a circular buffer of u64 encoded <timestamp,irq> values
300  * @count: the number of elements in the array
301  */
302 struct irq_timings {
303 	u64	values[IRQ_TIMINGS_SIZE];
304 	int	count;
305 };
306 
307 DECLARE_PER_CPU(struct irq_timings, irq_timings);
308 
309 extern void irq_timings_free(int irq);
310 extern int irq_timings_alloc(int irq);
311 
312 static inline void irq_remove_timings(struct irq_desc *desc)
313 {
314 	desc->istate &= ~IRQS_TIMINGS;
315 
316 	irq_timings_free(irq_desc_get_irq(desc));
317 }
318 
319 static inline void irq_setup_timings(struct irq_desc *desc, struct irqaction *act)
320 {
321 	int irq = irq_desc_get_irq(desc);
322 	int ret;
323 
324 	/*
325 	 * We don't need the measurement because the idle code already
326 	 * knows the next expiry event.
327 	 */
328 	if (act->flags & __IRQF_TIMER)
329 		return;
330 
331 	/*
332 	 * In case the timing allocation fails, we just want to warn,
333 	 * not fail, so letting the system boot anyway.
334 	 */
335 	ret = irq_timings_alloc(irq);
336 	if (ret) {
337 		pr_warn("Failed to allocate irq timing stats for irq%d (%d)",
338 			irq, ret);
339 		return;
340 	}
341 
342 	desc->istate |= IRQS_TIMINGS;
343 }
344 
345 extern void irq_timings_enable(void);
346 extern void irq_timings_disable(void);
347 
348 DECLARE_STATIC_KEY_FALSE(irq_timing_enabled);
349 
350 /*
351  * The interrupt number and the timestamp are encoded into a single
352  * u64 variable to optimize the size.
353  * 48 bit time stamp and 16 bit IRQ number is way sufficient.
354  *  Who cares an IRQ after 78 hours of idle time?
355  */
356 static inline u64 irq_timing_encode(u64 timestamp, int irq)
357 {
358 	return (timestamp << 16) | irq;
359 }
360 
361 static inline int irq_timing_decode(u64 value, u64 *timestamp)
362 {
363 	*timestamp = value >> 16;
364 	return value & U16_MAX;
365 }
366 
367 static __always_inline void irq_timings_push(u64 ts, int irq)
368 {
369 	struct irq_timings *timings = this_cpu_ptr(&irq_timings);
370 
371 	timings->values[timings->count & IRQ_TIMINGS_MASK] =
372 		irq_timing_encode(ts, irq);
373 
374 	timings->count++;
375 }
376 
377 /*
378  * The function record_irq_time is only called in one place in the
379  * interrupts handler. We want this function always inline so the code
380  * inside is embedded in the function and the static key branching
381  * code can act at the higher level. Without the explicit
382  * __always_inline we can end up with a function call and a small
383  * overhead in the hotpath for nothing.
384  */
385 static __always_inline void record_irq_time(struct irq_desc *desc)
386 {
387 	if (!static_branch_likely(&irq_timing_enabled))
388 		return;
389 
390 	if (desc->istate & IRQS_TIMINGS)
391 		irq_timings_push(local_clock(), irq_desc_get_irq(desc));
392 }
393 #else
394 static inline void irq_remove_timings(struct irq_desc *desc) {}
395 static inline void irq_setup_timings(struct irq_desc *desc,
396 				     struct irqaction *act) {};
397 static inline void record_irq_time(struct irq_desc *desc) {}
398 #endif /* CONFIG_IRQ_TIMINGS */
399 
400 
401 #ifdef CONFIG_GENERIC_IRQ_CHIP
402 void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
403 			   int num_ct, unsigned int irq_base,
404 			   void __iomem *reg_base, irq_flow_handler_t handler);
405 #else
406 static inline void
407 irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
408 		      int num_ct, unsigned int irq_base,
409 		      void __iomem *reg_base, irq_flow_handler_t handler) { }
410 #endif /* CONFIG_GENERIC_IRQ_CHIP */
411 
412 #ifdef CONFIG_GENERIC_PENDING_IRQ
413 static inline bool irq_can_move_pcntxt(struct irq_data *data)
414 {
415 	return !(data->chip->flags & IRQCHIP_MOVE_DEFERRED);
416 }
417 static inline bool irq_move_pending(struct irq_data *data)
418 {
419 	return irqd_is_setaffinity_pending(data);
420 }
421 static inline void
422 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
423 {
424 	cpumask_copy(desc->pending_mask, mask);
425 }
426 static inline void
427 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
428 {
429 	cpumask_copy(mask, desc->pending_mask);
430 }
431 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
432 {
433 	return desc->pending_mask;
434 }
435 bool irq_fixup_move_pending(struct irq_desc *desc, bool force_clear);
436 void irq_force_complete_move(struct irq_desc *desc);
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 void irq_force_complete_move(struct irq_desc *desc) { }
463 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
464 
465 #if !defined(CONFIG_IRQ_DOMAIN) || !defined(CONFIG_IRQ_DOMAIN_HIERARCHY)
466 static inline int irq_domain_activate_irq(struct irq_data *data, bool reserve)
467 {
468 	irqd_set_activated(data);
469 	return 0;
470 }
471 static inline void irq_domain_deactivate_irq(struct irq_data *data)
472 {
473 	irqd_clr_activated(data);
474 }
475 #endif
476 
477 static inline struct irq_data *irqd_get_parent_data(struct irq_data *irqd)
478 {
479 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
480 	return irqd->parent_data;
481 #else
482 	return NULL;
483 #endif
484 }
485 
486 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
487 #include <linux/debugfs.h>
488 
489 struct irq_bit_descr {
490 	unsigned int	mask;
491 	char		*name;
492 };
493 
494 #define BIT_MASK_DESCR(m)	{ .mask = m, .name = #m }
495 
496 void irq_debug_show_bits(struct seq_file *m, int ind, unsigned int state,
497 			 const struct irq_bit_descr *sd, int size);
498 
499 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc);
500 static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
501 {
502 	debugfs_remove(desc->debugfs_file);
503 	kfree(desc->dev_name);
504 }
505 void irq_debugfs_copy_devname(int irq, struct device *dev);
506 # ifdef CONFIG_IRQ_DOMAIN
507 void irq_domain_debugfs_init(struct dentry *root);
508 # else
509 static inline void irq_domain_debugfs_init(struct dentry *root)
510 {
511 }
512 # endif
513 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
514 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)
515 {
516 }
517 static inline void irq_remove_debugfs_entry(struct irq_desc *d)
518 {
519 }
520 static inline void irq_debugfs_copy_devname(int irq, struct device *dev)
521 {
522 }
523 #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
524