xref: /openbmc/linux/kernel/irq/internals.h (revision 0ad53fe3)
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  * IRQS_NMI			- irq line is used to deliver NMIs
53  */
54 enum {
55 	IRQS_AUTODETECT		= 0x00000001,
56 	IRQS_SPURIOUS_DISABLED	= 0x00000002,
57 	IRQS_POLL_INPROGRESS	= 0x00000008,
58 	IRQS_ONESHOT		= 0x00000020,
59 	IRQS_REPLAY		= 0x00000040,
60 	IRQS_WAITING		= 0x00000080,
61 	IRQS_PENDING		= 0x00000200,
62 	IRQS_SUSPENDED		= 0x00000800,
63 	IRQS_TIMINGS		= 0x00001000,
64 	IRQS_NMI		= 0x00002000,
65 };
66 
67 #include "debug.h"
68 #include "settings.h"
69 
70 extern int __irq_set_trigger(struct irq_desc *desc, unsigned long flags);
71 extern void __disable_irq(struct irq_desc *desc);
72 extern void __enable_irq(struct irq_desc *desc);
73 
74 #define IRQ_RESEND	true
75 #define IRQ_NORESEND	false
76 
77 #define IRQ_START_FORCE	true
78 #define IRQ_START_COND	false
79 
80 extern int irq_activate(struct irq_desc *desc);
81 extern int irq_activate_and_startup(struct irq_desc *desc, bool resend);
82 extern int irq_startup(struct irq_desc *desc, bool resend, bool force);
83 
84 extern void irq_shutdown(struct irq_desc *desc);
85 extern void irq_shutdown_and_deactivate(struct irq_desc *desc);
86 extern void irq_enable(struct irq_desc *desc);
87 extern void irq_disable(struct irq_desc *desc);
88 extern void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu);
89 extern void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu);
90 extern void mask_irq(struct irq_desc *desc);
91 extern void unmask_irq(struct irq_desc *desc);
92 extern void unmask_threaded_irq(struct irq_desc *desc);
93 
94 #ifdef CONFIG_SPARSE_IRQ
95 static inline void irq_mark_irq(unsigned int irq) { }
96 #else
97 extern void irq_mark_irq(unsigned int irq);
98 #endif
99 
100 extern int __irq_get_irqchip_state(struct irq_data *data,
101 				   enum irqchip_irq_state which,
102 				   bool *state);
103 
104 extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr);
105 
106 irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags);
107 irqreturn_t handle_irq_event_percpu(struct irq_desc *desc);
108 irqreturn_t handle_irq_event(struct irq_desc *desc);
109 
110 /* Resending of interrupts :*/
111 int check_irq_resend(struct irq_desc *desc, bool inject);
112 bool irq_wait_for_poll(struct irq_desc *desc);
113 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
114 
115 #ifdef CONFIG_PROC_FS
116 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
117 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
118 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
119 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
120 #else
121 static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
122 static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { }
123 static inline void register_handler_proc(unsigned int irq,
124 					 struct irqaction *action) { }
125 static inline void unregister_handler_proc(unsigned int irq,
126 					   struct irqaction *action) { }
127 #endif
128 
129 extern bool irq_can_set_affinity_usr(unsigned int irq);
130 
131 extern void irq_set_thread_affinity(struct irq_desc *desc);
132 
133 extern int irq_do_set_affinity(struct irq_data *data,
134 			       const struct cpumask *dest, bool force);
135 
136 #ifdef CONFIG_SMP
137 extern int irq_setup_affinity(struct irq_desc *desc);
138 #else
139 static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }
140 #endif
141 
142 /* Inline functions for support of irq chips on slow busses */
143 static inline void chip_bus_lock(struct irq_desc *desc)
144 {
145 	if (unlikely(desc->irq_data.chip->irq_bus_lock))
146 		desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
147 }
148 
149 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
150 {
151 	if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
152 		desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
153 }
154 
155 #define _IRQ_DESC_CHECK		(1 << 0)
156 #define _IRQ_DESC_PERCPU	(1 << 1)
157 
158 #define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)
159 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
160 
161 #define for_each_action_of_desc(desc, act)			\
162 	for (act = desc->action; act; act = act->next)
163 
164 struct irq_desc *
165 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
166 		    unsigned int check);
167 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
168 
169 static inline struct irq_desc *
170 irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)
171 {
172 	return __irq_get_desc_lock(irq, flags, true, check);
173 }
174 
175 static inline void
176 irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags)
177 {
178 	__irq_put_desc_unlock(desc, flags, true);
179 }
180 
181 static inline struct irq_desc *
182 irq_get_desc_lock(unsigned int irq, unsigned long *flags, unsigned int check)
183 {
184 	return __irq_get_desc_lock(irq, flags, false, check);
185 }
186 
187 static inline void
188 irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags)
189 {
190 	__irq_put_desc_unlock(desc, flags, false);
191 }
192 
193 #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
194 
195 static inline unsigned int irqd_get(struct irq_data *d)
196 {
197 	return __irqd_to_state(d);
198 }
199 
200 /*
201  * Manipulation functions for irq_data.state
202  */
203 static inline void irqd_set_move_pending(struct irq_data *d)
204 {
205 	__irqd_to_state(d) |= IRQD_SETAFFINITY_PENDING;
206 }
207 
208 static inline void irqd_clr_move_pending(struct irq_data *d)
209 {
210 	__irqd_to_state(d) &= ~IRQD_SETAFFINITY_PENDING;
211 }
212 
213 static inline void irqd_set_managed_shutdown(struct irq_data *d)
214 {
215 	__irqd_to_state(d) |= IRQD_MANAGED_SHUTDOWN;
216 }
217 
218 static inline void irqd_clr_managed_shutdown(struct irq_data *d)
219 {
220 	__irqd_to_state(d) &= ~IRQD_MANAGED_SHUTDOWN;
221 }
222 
223 static inline void irqd_clear(struct irq_data *d, unsigned int mask)
224 {
225 	__irqd_to_state(d) &= ~mask;
226 }
227 
228 static inline void irqd_set(struct irq_data *d, unsigned int mask)
229 {
230 	__irqd_to_state(d) |= mask;
231 }
232 
233 static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
234 {
235 	return __irqd_to_state(d) & mask;
236 }
237 
238 static inline void irq_state_set_disabled(struct irq_desc *desc)
239 {
240 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
241 }
242 
243 static inline void irq_state_set_masked(struct irq_desc *desc)
244 {
245 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
246 }
247 
248 #undef __irqd_to_state
249 
250 static inline void __kstat_incr_irqs_this_cpu(struct irq_desc *desc)
251 {
252 	__this_cpu_inc(*desc->kstat_irqs);
253 	__this_cpu_inc(kstat.irqs_sum);
254 }
255 
256 static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
257 {
258 	__kstat_incr_irqs_this_cpu(desc);
259 	desc->tot_count++;
260 }
261 
262 static inline int irq_desc_get_node(struct irq_desc *desc)
263 {
264 	return irq_common_data_get_node(&desc->irq_common_data);
265 }
266 
267 static inline int irq_desc_is_chained(struct irq_desc *desc)
268 {
269 	return (desc->action && desc->action == &chained_action);
270 }
271 
272 #ifdef CONFIG_PM_SLEEP
273 bool irq_pm_check_wakeup(struct irq_desc *desc);
274 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
275 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
276 #else
277 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
278 static inline void
279 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
280 static inline void
281 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
282 #endif
283 
284 #ifdef CONFIG_IRQ_TIMINGS
285 
286 #define IRQ_TIMINGS_SHIFT	5
287 #define IRQ_TIMINGS_SIZE	(1 << IRQ_TIMINGS_SHIFT)
288 #define IRQ_TIMINGS_MASK	(IRQ_TIMINGS_SIZE - 1)
289 
290 /**
291  * struct irq_timings - irq timings storing structure
292  * @values: a circular buffer of u64 encoded <timestamp,irq> values
293  * @count: the number of elements in the array
294  */
295 struct irq_timings {
296 	u64	values[IRQ_TIMINGS_SIZE];
297 	int	count;
298 };
299 
300 DECLARE_PER_CPU(struct irq_timings, irq_timings);
301 
302 extern void irq_timings_free(int irq);
303 extern int irq_timings_alloc(int irq);
304 
305 static inline void irq_remove_timings(struct irq_desc *desc)
306 {
307 	desc->istate &= ~IRQS_TIMINGS;
308 
309 	irq_timings_free(irq_desc_get_irq(desc));
310 }
311 
312 static inline void irq_setup_timings(struct irq_desc *desc, struct irqaction *act)
313 {
314 	int irq = irq_desc_get_irq(desc);
315 	int ret;
316 
317 	/*
318 	 * We don't need the measurement because the idle code already
319 	 * knows the next expiry event.
320 	 */
321 	if (act->flags & __IRQF_TIMER)
322 		return;
323 
324 	/*
325 	 * In case the timing allocation fails, we just want to warn,
326 	 * not fail, so letting the system boot anyway.
327 	 */
328 	ret = irq_timings_alloc(irq);
329 	if (ret) {
330 		pr_warn("Failed to allocate irq timing stats for irq%d (%d)",
331 			irq, ret);
332 		return;
333 	}
334 
335 	desc->istate |= IRQS_TIMINGS;
336 }
337 
338 extern void irq_timings_enable(void);
339 extern void irq_timings_disable(void);
340 
341 DECLARE_STATIC_KEY_FALSE(irq_timing_enabled);
342 
343 /*
344  * The interrupt number and the timestamp are encoded into a single
345  * u64 variable to optimize the size.
346  * 48 bit time stamp and 16 bit IRQ number is way sufficient.
347  *  Who cares an IRQ after 78 hours of idle time?
348  */
349 static inline u64 irq_timing_encode(u64 timestamp, int irq)
350 {
351 	return (timestamp << 16) | irq;
352 }
353 
354 static inline int irq_timing_decode(u64 value, u64 *timestamp)
355 {
356 	*timestamp = value >> 16;
357 	return value & U16_MAX;
358 }
359 
360 static __always_inline void irq_timings_push(u64 ts, int irq)
361 {
362 	struct irq_timings *timings = this_cpu_ptr(&irq_timings);
363 
364 	timings->values[timings->count & IRQ_TIMINGS_MASK] =
365 		irq_timing_encode(ts, irq);
366 
367 	timings->count++;
368 }
369 
370 /*
371  * The function record_irq_time is only called in one place in the
372  * interrupts handler. We want this function always inline so the code
373  * inside is embedded in the function and the static key branching
374  * code can act at the higher level. Without the explicit
375  * __always_inline we can end up with a function call and a small
376  * overhead in the hotpath for nothing.
377  */
378 static __always_inline void record_irq_time(struct irq_desc *desc)
379 {
380 	if (!static_branch_likely(&irq_timing_enabled))
381 		return;
382 
383 	if (desc->istate & IRQS_TIMINGS)
384 		irq_timings_push(local_clock(), irq_desc_get_irq(desc));
385 }
386 #else
387 static inline void irq_remove_timings(struct irq_desc *desc) {}
388 static inline void irq_setup_timings(struct irq_desc *desc,
389 				     struct irqaction *act) {};
390 static inline void record_irq_time(struct irq_desc *desc) {}
391 #endif /* CONFIG_IRQ_TIMINGS */
392 
393 
394 #ifdef CONFIG_GENERIC_IRQ_CHIP
395 void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
396 			   int num_ct, unsigned int irq_base,
397 			   void __iomem *reg_base, irq_flow_handler_t handler);
398 #else
399 static inline void
400 irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
401 		      int num_ct, unsigned int irq_base,
402 		      void __iomem *reg_base, irq_flow_handler_t handler) { }
403 #endif /* CONFIG_GENERIC_IRQ_CHIP */
404 
405 #ifdef CONFIG_GENERIC_PENDING_IRQ
406 static inline bool irq_can_move_pcntxt(struct irq_data *data)
407 {
408 	return irqd_can_move_in_process_context(data);
409 }
410 static inline bool irq_move_pending(struct irq_data *data)
411 {
412 	return irqd_is_setaffinity_pending(data);
413 }
414 static inline void
415 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
416 {
417 	cpumask_copy(desc->pending_mask, mask);
418 }
419 static inline void
420 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
421 {
422 	cpumask_copy(mask, desc->pending_mask);
423 }
424 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
425 {
426 	return desc->pending_mask;
427 }
428 static inline bool handle_enforce_irqctx(struct irq_data *data)
429 {
430 	return irqd_is_handle_enforce_irqctx(data);
431 }
432 bool irq_fixup_move_pending(struct irq_desc *desc, bool force_clear);
433 #else /* CONFIG_GENERIC_PENDING_IRQ */
434 static inline bool irq_can_move_pcntxt(struct irq_data *data)
435 {
436 	return true;
437 }
438 static inline bool irq_move_pending(struct irq_data *data)
439 {
440 	return false;
441 }
442 static inline void
443 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
444 {
445 }
446 static inline void
447 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
448 {
449 }
450 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
451 {
452 	return NULL;
453 }
454 static inline bool irq_fixup_move_pending(struct irq_desc *desc, bool fclear)
455 {
456 	return false;
457 }
458 static inline bool handle_enforce_irqctx(struct irq_data *data)
459 {
460 	return false;
461 }
462 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
463 
464 #if !defined(CONFIG_IRQ_DOMAIN) || !defined(CONFIG_IRQ_DOMAIN_HIERARCHY)
465 static inline int irq_domain_activate_irq(struct irq_data *data, bool reserve)
466 {
467 	irqd_set_activated(data);
468 	return 0;
469 }
470 static inline void irq_domain_deactivate_irq(struct irq_data *data)
471 {
472 	irqd_clr_activated(data);
473 }
474 #endif
475 
476 static inline struct irq_data *irqd_get_parent_data(struct irq_data *irqd)
477 {
478 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
479 	return irqd->parent_data;
480 #else
481 	return NULL;
482 #endif
483 }
484 
485 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
486 #include <linux/debugfs.h>
487 
488 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc);
489 static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
490 {
491 	debugfs_remove(desc->debugfs_file);
492 	kfree(desc->dev_name);
493 }
494 void irq_debugfs_copy_devname(int irq, struct device *dev);
495 # ifdef CONFIG_IRQ_DOMAIN
496 void irq_domain_debugfs_init(struct dentry *root);
497 # else
498 static inline void irq_domain_debugfs_init(struct dentry *root)
499 {
500 }
501 # endif
502 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
503 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)
504 {
505 }
506 static inline void irq_remove_debugfs_entry(struct irq_desc *d)
507 {
508 }
509 static inline void irq_debugfs_copy_devname(int irq, struct device *dev)
510 {
511 }
512 #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
513