xref: /openbmc/linux/kernel/irq/internals.h (revision a44e4f3a)
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 void check_irq_resend(struct irq_desc *desc);
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 int irq_select_affinity_usr(unsigned int irq);
132 
133 extern void irq_set_thread_affinity(struct irq_desc *desc);
134 
135 extern int irq_do_set_affinity(struct irq_data *data,
136 			       const struct cpumask *dest, bool force);
137 
138 #ifdef CONFIG_SMP
139 extern int irq_setup_affinity(struct irq_desc *desc);
140 #else
141 static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }
142 #endif
143 
144 /* Inline functions for support of irq chips on slow busses */
145 static inline void chip_bus_lock(struct irq_desc *desc)
146 {
147 	if (unlikely(desc->irq_data.chip->irq_bus_lock))
148 		desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
149 }
150 
151 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
152 {
153 	if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
154 		desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
155 }
156 
157 #define _IRQ_DESC_CHECK		(1 << 0)
158 #define _IRQ_DESC_PERCPU	(1 << 1)
159 
160 #define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)
161 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
162 
163 #define for_each_action_of_desc(desc, act)			\
164 	for (act = desc->action; act; act = act->next)
165 
166 struct irq_desc *
167 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
168 		    unsigned int check);
169 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
170 
171 static inline struct irq_desc *
172 irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)
173 {
174 	return __irq_get_desc_lock(irq, flags, true, check);
175 }
176 
177 static inline void
178 irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags)
179 {
180 	__irq_put_desc_unlock(desc, flags, true);
181 }
182 
183 static inline struct irq_desc *
184 irq_get_desc_lock(unsigned int irq, unsigned long *flags, unsigned int check)
185 {
186 	return __irq_get_desc_lock(irq, flags, false, check);
187 }
188 
189 static inline void
190 irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags)
191 {
192 	__irq_put_desc_unlock(desc, flags, false);
193 }
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);
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 #ifdef CONFIG_PM_SLEEP
275 bool irq_pm_check_wakeup(struct irq_desc *desc);
276 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
277 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
278 #else
279 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
280 static inline void
281 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
282 static inline void
283 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
284 #endif
285 
286 #ifdef CONFIG_IRQ_TIMINGS
287 
288 #define IRQ_TIMINGS_SHIFT	5
289 #define IRQ_TIMINGS_SIZE	(1 << IRQ_TIMINGS_SHIFT)
290 #define IRQ_TIMINGS_MASK	(IRQ_TIMINGS_SIZE - 1)
291 
292 /**
293  * struct irq_timings - irq timings storing structure
294  * @values: a circular buffer of u64 encoded <timestamp,irq> values
295  * @count: the number of elements in the array
296  */
297 struct irq_timings {
298 	u64	values[IRQ_TIMINGS_SIZE];
299 	int	count;
300 };
301 
302 DECLARE_PER_CPU(struct irq_timings, irq_timings);
303 
304 extern void irq_timings_free(int irq);
305 extern int irq_timings_alloc(int irq);
306 
307 static inline void irq_remove_timings(struct irq_desc *desc)
308 {
309 	desc->istate &= ~IRQS_TIMINGS;
310 
311 	irq_timings_free(irq_desc_get_irq(desc));
312 }
313 
314 static inline void irq_setup_timings(struct irq_desc *desc, struct irqaction *act)
315 {
316 	int irq = irq_desc_get_irq(desc);
317 	int ret;
318 
319 	/*
320 	 * We don't need the measurement because the idle code already
321 	 * knows the next expiry event.
322 	 */
323 	if (act->flags & __IRQF_TIMER)
324 		return;
325 
326 	/*
327 	 * In case the timing allocation fails, we just want to warn,
328 	 * not fail, so letting the system boot anyway.
329 	 */
330 	ret = irq_timings_alloc(irq);
331 	if (ret) {
332 		pr_warn("Failed to allocate irq timing stats for irq%d (%d)",
333 			irq, ret);
334 		return;
335 	}
336 
337 	desc->istate |= IRQS_TIMINGS;
338 }
339 
340 extern void irq_timings_enable(void);
341 extern void irq_timings_disable(void);
342 
343 DECLARE_STATIC_KEY_FALSE(irq_timing_enabled);
344 
345 /*
346  * The interrupt number and the timestamp are encoded into a single
347  * u64 variable to optimize the size.
348  * 48 bit time stamp and 16 bit IRQ number is way sufficient.
349  *  Who cares an IRQ after 78 hours of idle time?
350  */
351 static inline u64 irq_timing_encode(u64 timestamp, int irq)
352 {
353 	return (timestamp << 16) | irq;
354 }
355 
356 static inline int irq_timing_decode(u64 value, u64 *timestamp)
357 {
358 	*timestamp = value >> 16;
359 	return value & U16_MAX;
360 }
361 
362 static __always_inline void irq_timings_push(u64 ts, int irq)
363 {
364 	struct irq_timings *timings = this_cpu_ptr(&irq_timings);
365 
366 	timings->values[timings->count & IRQ_TIMINGS_MASK] =
367 		irq_timing_encode(ts, irq);
368 
369 	timings->count++;
370 }
371 
372 /*
373  * The function record_irq_time is only called in one place in the
374  * interrupts handler. We want this function always inline so the code
375  * inside is embedded in the function and the static key branching
376  * code can act at the higher level. Without the explicit
377  * __always_inline we can end up with a function call and a small
378  * overhead in the hotpath for nothing.
379  */
380 static __always_inline void record_irq_time(struct irq_desc *desc)
381 {
382 	if (!static_branch_likely(&irq_timing_enabled))
383 		return;
384 
385 	if (desc->istate & IRQS_TIMINGS)
386 		irq_timings_push(local_clock(), irq_desc_get_irq(desc));
387 }
388 #else
389 static inline void irq_remove_timings(struct irq_desc *desc) {}
390 static inline void irq_setup_timings(struct irq_desc *desc,
391 				     struct irqaction *act) {};
392 static inline void record_irq_time(struct irq_desc *desc) {}
393 #endif /* CONFIG_IRQ_TIMINGS */
394 
395 
396 #ifdef CONFIG_GENERIC_IRQ_CHIP
397 void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
398 			   int num_ct, unsigned int irq_base,
399 			   void __iomem *reg_base, irq_flow_handler_t handler);
400 #else
401 static inline void
402 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 #endif /* CONFIG_GENERIC_IRQ_CHIP */
406 
407 #ifdef CONFIG_GENERIC_PENDING_IRQ
408 static inline bool irq_can_move_pcntxt(struct irq_data *data)
409 {
410 	return irqd_can_move_in_process_context(data);
411 }
412 static inline bool irq_move_pending(struct irq_data *data)
413 {
414 	return irqd_is_setaffinity_pending(data);
415 }
416 static inline void
417 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
418 {
419 	cpumask_copy(desc->pending_mask, mask);
420 }
421 static inline void
422 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
423 {
424 	cpumask_copy(mask, desc->pending_mask);
425 }
426 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
427 {
428 	return desc->pending_mask;
429 }
430 bool irq_fixup_move_pending(struct irq_desc *desc, bool force_clear);
431 #else /* CONFIG_GENERIC_PENDING_IRQ */
432 static inline bool irq_can_move_pcntxt(struct irq_data *data)
433 {
434 	return true;
435 }
436 static inline bool irq_move_pending(struct irq_data *data)
437 {
438 	return false;
439 }
440 static inline void
441 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
442 {
443 }
444 static inline void
445 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
446 {
447 }
448 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
449 {
450 	return NULL;
451 }
452 static inline bool irq_fixup_move_pending(struct irq_desc *desc, bool fclear)
453 {
454 	return false;
455 }
456 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
457 
458 #if !defined(CONFIG_IRQ_DOMAIN) || !defined(CONFIG_IRQ_DOMAIN_HIERARCHY)
459 static inline int irq_domain_activate_irq(struct irq_data *data, bool reserve)
460 {
461 	irqd_set_activated(data);
462 	return 0;
463 }
464 static inline void irq_domain_deactivate_irq(struct irq_data *data)
465 {
466 	irqd_clr_activated(data);
467 }
468 #endif
469 
470 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
471 #include <linux/debugfs.h>
472 
473 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc);
474 static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
475 {
476 	debugfs_remove(desc->debugfs_file);
477 	kfree(desc->dev_name);
478 }
479 void irq_debugfs_copy_devname(int irq, struct device *dev);
480 # ifdef CONFIG_IRQ_DOMAIN
481 void irq_domain_debugfs_init(struct dentry *root);
482 # else
483 static inline void irq_domain_debugfs_init(struct dentry *root)
484 {
485 }
486 # endif
487 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
488 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)
489 {
490 }
491 static inline void irq_remove_debugfs_entry(struct irq_desc *d)
492 {
493 }
494 static inline void irq_debugfs_copy_devname(int irq, struct device *dev)
495 {
496 }
497 #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
498