xref: /linux/kernel/irq/internals.h (revision e21f9e2e862e9eb3dd64eaddb6256b3e5098660f)
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  */
33 enum {
34 	IRQTF_RUNTHREAD,
35 	IRQTF_WARNED,
36 	IRQTF_AFFINITY,
37 	IRQTF_FORCED_THREAD,
38 };
39 
40 /*
41  * Bit masks for desc->core_internal_state__do_not_mess_with_it
42  *
43  * IRQS_AUTODETECT		- autodetection in progress
44  * IRQS_SPURIOUS_DISABLED	- was disabled due to spurious interrupt
45  *				  detection
46  * IRQS_POLL_INPROGRESS		- polling in progress
47  * IRQS_ONESHOT			- irq is not unmasked in primary handler
48  * IRQS_REPLAY			- irq is replayed
49  * IRQS_WAITING			- irq is waiting
50  * IRQS_PENDING			- irq is pending and replayed later
51  * IRQS_SUSPENDED		- irq is suspended
52  */
53 enum {
54 	IRQS_AUTODETECT		= 0x00000001,
55 	IRQS_SPURIOUS_DISABLED	= 0x00000002,
56 	IRQS_POLL_INPROGRESS	= 0x00000008,
57 	IRQS_ONESHOT		= 0x00000020,
58 	IRQS_REPLAY		= 0x00000040,
59 	IRQS_WAITING		= 0x00000080,
60 	IRQS_PENDING		= 0x00000200,
61 	IRQS_SUSPENDED		= 0x00000800,
62 	IRQS_TIMINGS		= 0x00001000,
63 };
64 
65 #include "debug.h"
66 #include "settings.h"
67 
68 extern int __irq_set_trigger(struct irq_desc *desc, unsigned long flags);
69 extern void __disable_irq(struct irq_desc *desc);
70 extern void __enable_irq(struct irq_desc *desc);
71 
72 #define IRQ_RESEND	true
73 #define IRQ_NORESEND	false
74 
75 #define IRQ_START_FORCE	true
76 #define IRQ_START_COND	false
77 
78 extern int irq_activate(struct irq_desc *desc);
79 extern int irq_activate_and_startup(struct irq_desc *desc, bool resend);
80 extern int irq_startup(struct irq_desc *desc, bool resend, bool force);
81 
82 extern void irq_shutdown(struct irq_desc *desc);
83 extern void irq_enable(struct irq_desc *desc);
84 extern void irq_disable(struct irq_desc *desc);
85 extern void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu);
86 extern void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu);
87 extern void mask_irq(struct irq_desc *desc);
88 extern void unmask_irq(struct irq_desc *desc);
89 extern void unmask_threaded_irq(struct irq_desc *desc);
90 
91 #ifdef CONFIG_SPARSE_IRQ
92 static inline void irq_mark_irq(unsigned int irq) { }
93 #else
94 extern void irq_mark_irq(unsigned int irq);
95 #endif
96 
97 extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr);
98 
99 irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags);
100 irqreturn_t handle_irq_event_percpu(struct irq_desc *desc);
101 irqreturn_t handle_irq_event(struct irq_desc *desc);
102 
103 /* Resending of interrupts :*/
104 void check_irq_resend(struct irq_desc *desc);
105 bool irq_wait_for_poll(struct irq_desc *desc);
106 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
107 
108 #ifdef CONFIG_PROC_FS
109 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
110 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
111 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
112 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
113 #else
114 static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
115 static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { }
116 static inline void register_handler_proc(unsigned int irq,
117 					 struct irqaction *action) { }
118 static inline void unregister_handler_proc(unsigned int irq,
119 					   struct irqaction *action) { }
120 #endif
121 
122 extern bool irq_can_set_affinity_usr(unsigned int irq);
123 
124 extern int irq_select_affinity_usr(unsigned int irq);
125 
126 extern void irq_set_thread_affinity(struct irq_desc *desc);
127 
128 extern int irq_do_set_affinity(struct irq_data *data,
129 			       const struct cpumask *dest, bool force);
130 
131 #ifdef CONFIG_SMP
132 extern int irq_setup_affinity(struct irq_desc *desc);
133 #else
134 static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }
135 #endif
136 
137 /* Inline functions for support of irq chips on slow busses */
138 static inline void chip_bus_lock(struct irq_desc *desc)
139 {
140 	if (unlikely(desc->irq_data.chip->irq_bus_lock))
141 		desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
142 }
143 
144 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
145 {
146 	if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
147 		desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
148 }
149 
150 #define _IRQ_DESC_CHECK		(1 << 0)
151 #define _IRQ_DESC_PERCPU	(1 << 1)
152 
153 #define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)
154 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
155 
156 #define for_each_action_of_desc(desc, act)			\
157 	for (act = desc->action; act; act = act->next)
158 
159 struct irq_desc *
160 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
161 		    unsigned int check);
162 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
163 
164 static inline struct irq_desc *
165 irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)
166 {
167 	return __irq_get_desc_lock(irq, flags, true, check);
168 }
169 
170 static inline void
171 irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags)
172 {
173 	__irq_put_desc_unlock(desc, flags, true);
174 }
175 
176 static inline struct irq_desc *
177 irq_get_desc_lock(unsigned int irq, unsigned long *flags, unsigned int check)
178 {
179 	return __irq_get_desc_lock(irq, flags, false, check);
180 }
181 
182 static inline void
183 irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags)
184 {
185 	__irq_put_desc_unlock(desc, flags, false);
186 }
187 
188 #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
189 
190 static inline unsigned int irqd_get(struct irq_data *d)
191 {
192 	return __irqd_to_state(d);
193 }
194 
195 /*
196  * Manipulation functions for irq_data.state
197  */
198 static inline void irqd_set_move_pending(struct irq_data *d)
199 {
200 	__irqd_to_state(d) |= IRQD_SETAFFINITY_PENDING;
201 }
202 
203 static inline void irqd_clr_move_pending(struct irq_data *d)
204 {
205 	__irqd_to_state(d) &= ~IRQD_SETAFFINITY_PENDING;
206 }
207 
208 static inline void irqd_set_managed_shutdown(struct irq_data *d)
209 {
210 	__irqd_to_state(d) |= IRQD_MANAGED_SHUTDOWN;
211 }
212 
213 static inline void irqd_clr_managed_shutdown(struct irq_data *d)
214 {
215 	__irqd_to_state(d) &= ~IRQD_MANAGED_SHUTDOWN;
216 }
217 
218 static inline void irqd_clear(struct irq_data *d, unsigned int mask)
219 {
220 	__irqd_to_state(d) &= ~mask;
221 }
222 
223 static inline void irqd_set(struct irq_data *d, unsigned int mask)
224 {
225 	__irqd_to_state(d) |= mask;
226 }
227 
228 static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
229 {
230 	return __irqd_to_state(d) & mask;
231 }
232 
233 static inline void irq_state_set_disabled(struct irq_desc *desc)
234 {
235 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
236 }
237 
238 static inline void irq_state_set_masked(struct irq_desc *desc)
239 {
240 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
241 }
242 
243 #undef __irqd_to_state
244 
245 static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
246 {
247 	__this_cpu_inc(*desc->kstat_irqs);
248 	__this_cpu_inc(kstat.irqs_sum);
249 }
250 
251 static inline int irq_desc_get_node(struct irq_desc *desc)
252 {
253 	return irq_common_data_get_node(&desc->irq_common_data);
254 }
255 
256 static inline int irq_desc_is_chained(struct irq_desc *desc)
257 {
258 	return (desc->action && desc->action == &chained_action);
259 }
260 
261 #ifdef CONFIG_PM_SLEEP
262 bool irq_pm_check_wakeup(struct irq_desc *desc);
263 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
264 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
265 #else
266 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
267 static inline void
268 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
269 static inline void
270 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
271 #endif
272 
273 #ifdef CONFIG_IRQ_TIMINGS
274 
275 #define IRQ_TIMINGS_SHIFT	5
276 #define IRQ_TIMINGS_SIZE	(1 << IRQ_TIMINGS_SHIFT)
277 #define IRQ_TIMINGS_MASK	(IRQ_TIMINGS_SIZE - 1)
278 
279 /**
280  * struct irq_timings - irq timings storing structure
281  * @values: a circular buffer of u64 encoded <timestamp,irq> values
282  * @count: the number of elements in the array
283  */
284 struct irq_timings {
285 	u64	values[IRQ_TIMINGS_SIZE];
286 	int	count;
287 };
288 
289 DECLARE_PER_CPU(struct irq_timings, irq_timings);
290 
291 extern void irq_timings_free(int irq);
292 extern int irq_timings_alloc(int irq);
293 
294 static inline void irq_remove_timings(struct irq_desc *desc)
295 {
296 	desc->istate &= ~IRQS_TIMINGS;
297 
298 	irq_timings_free(irq_desc_get_irq(desc));
299 }
300 
301 static inline void irq_setup_timings(struct irq_desc *desc, struct irqaction *act)
302 {
303 	int irq = irq_desc_get_irq(desc);
304 	int ret;
305 
306 	/*
307 	 * We don't need the measurement because the idle code already
308 	 * knows the next expiry event.
309 	 */
310 	if (act->flags & __IRQF_TIMER)
311 		return;
312 
313 	/*
314 	 * In case the timing allocation fails, we just want to warn,
315 	 * not fail, so letting the system boot anyway.
316 	 */
317 	ret = irq_timings_alloc(irq);
318 	if (ret) {
319 		pr_warn("Failed to allocate irq timing stats for irq%d (%d)",
320 			irq, ret);
321 		return;
322 	}
323 
324 	desc->istate |= IRQS_TIMINGS;
325 }
326 
327 extern void irq_timings_enable(void);
328 extern void irq_timings_disable(void);
329 
330 DECLARE_STATIC_KEY_FALSE(irq_timing_enabled);
331 
332 /*
333  * The interrupt number and the timestamp are encoded into a single
334  * u64 variable to optimize the size.
335  * 48 bit time stamp and 16 bit IRQ number is way sufficient.
336  *  Who cares an IRQ after 78 hours of idle time?
337  */
338 static inline u64 irq_timing_encode(u64 timestamp, int irq)
339 {
340 	return (timestamp << 16) | irq;
341 }
342 
343 static inline int irq_timing_decode(u64 value, u64 *timestamp)
344 {
345 	*timestamp = value >> 16;
346 	return value & U16_MAX;
347 }
348 
349 /*
350  * The function record_irq_time is only called in one place in the
351  * interrupts handler. We want this function always inline so the code
352  * inside is embedded in the function and the static key branching
353  * code can act at the higher level. Without the explicit
354  * __always_inline we can end up with a function call and a small
355  * overhead in the hotpath for nothing.
356  */
357 static __always_inline void record_irq_time(struct irq_desc *desc)
358 {
359 	if (!static_branch_likely(&irq_timing_enabled))
360 		return;
361 
362 	if (desc->istate & IRQS_TIMINGS) {
363 		struct irq_timings *timings = this_cpu_ptr(&irq_timings);
364 
365 		timings->values[timings->count & IRQ_TIMINGS_MASK] =
366 			irq_timing_encode(local_clock(),
367 					  irq_desc_get_irq(desc));
368 
369 		timings->count++;
370 	}
371 }
372 #else
373 static inline void irq_remove_timings(struct irq_desc *desc) {}
374 static inline void irq_setup_timings(struct irq_desc *desc,
375 				     struct irqaction *act) {};
376 static inline void record_irq_time(struct irq_desc *desc) {}
377 #endif /* CONFIG_IRQ_TIMINGS */
378 
379 
380 #ifdef CONFIG_GENERIC_IRQ_CHIP
381 void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
382 			   int num_ct, unsigned int irq_base,
383 			   void __iomem *reg_base, irq_flow_handler_t handler);
384 #else
385 static inline void
386 irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
387 		      int num_ct, unsigned int irq_base,
388 		      void __iomem *reg_base, irq_flow_handler_t handler) { }
389 #endif /* CONFIG_GENERIC_IRQ_CHIP */
390 
391 #ifdef CONFIG_GENERIC_PENDING_IRQ
392 static inline bool irq_can_move_pcntxt(struct irq_data *data)
393 {
394 	return irqd_can_move_in_process_context(data);
395 }
396 static inline bool irq_move_pending(struct irq_data *data)
397 {
398 	return irqd_is_setaffinity_pending(data);
399 }
400 static inline void
401 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
402 {
403 	cpumask_copy(desc->pending_mask, mask);
404 }
405 static inline void
406 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
407 {
408 	cpumask_copy(mask, desc->pending_mask);
409 }
410 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
411 {
412 	return desc->pending_mask;
413 }
414 bool irq_fixup_move_pending(struct irq_desc *desc, bool force_clear);
415 #else /* CONFIG_GENERIC_PENDING_IRQ */
416 static inline bool irq_can_move_pcntxt(struct irq_data *data)
417 {
418 	return true;
419 }
420 static inline bool irq_move_pending(struct irq_data *data)
421 {
422 	return false;
423 }
424 static inline void
425 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
426 {
427 }
428 static inline void
429 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
430 {
431 }
432 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
433 {
434 	return NULL;
435 }
436 static inline bool irq_fixup_move_pending(struct irq_desc *desc, bool fclear)
437 {
438 	return false;
439 }
440 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
441 
442 #if !defined(CONFIG_IRQ_DOMAIN) || !defined(CONFIG_IRQ_DOMAIN_HIERARCHY)
443 static inline int irq_domain_activate_irq(struct irq_data *data, bool reserve)
444 {
445 	irqd_set_activated(data);
446 	return 0;
447 }
448 static inline void irq_domain_deactivate_irq(struct irq_data *data)
449 {
450 	irqd_clr_activated(data);
451 }
452 #endif
453 
454 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
455 #include <linux/debugfs.h>
456 
457 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc);
458 static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
459 {
460 	debugfs_remove(desc->debugfs_file);
461 	kfree(desc->dev_name);
462 }
463 void irq_debugfs_copy_devname(int irq, struct device *dev);
464 # ifdef CONFIG_IRQ_DOMAIN
465 void irq_domain_debugfs_init(struct dentry *root);
466 # else
467 static inline void irq_domain_debugfs_init(struct dentry *root)
468 {
469 }
470 # endif
471 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
472 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)
473 {
474 }
475 static inline void irq_remove_debugfs_entry(struct irq_desc *d)
476 {
477 }
478 static inline void irq_debugfs_copy_devname(int irq, struct device *dev)
479 {
480 }
481 #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
482