xref: /openbmc/linux/kernel/irq/internals.h (revision dea54fba)
1 /*
2  * IRQ subsystem internal functions and variables:
3  *
4  * Do not ever include this file from anything else than
5  * kernel/irq/. Do not even think about using any information outside
6  * of this file for your non core code.
7  */
8 #include <linux/irqdesc.h>
9 #include <linux/kernel_stat.h>
10 #include <linux/pm_runtime.h>
11 #include <linux/sched/clock.h>
12 
13 #ifdef CONFIG_SPARSE_IRQ
14 # define IRQ_BITMAP_BITS	(NR_IRQS + 8196)
15 #else
16 # define IRQ_BITMAP_BITS	NR_IRQS
17 #endif
18 
19 #define istate core_internal_state__do_not_mess_with_it
20 
21 extern bool noirqdebug;
22 
23 extern struct irqaction chained_action;
24 
25 /*
26  * Bits used by threaded handlers:
27  * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run
28  * IRQTF_WARNED    - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed
29  * IRQTF_AFFINITY  - irq thread is requested to adjust affinity
30  * IRQTF_FORCED_THREAD  - irq action is force threaded
31  */
32 enum {
33 	IRQTF_RUNTHREAD,
34 	IRQTF_WARNED,
35 	IRQTF_AFFINITY,
36 	IRQTF_FORCED_THREAD,
37 };
38 
39 /*
40  * Bit masks for desc->core_internal_state__do_not_mess_with_it
41  *
42  * IRQS_AUTODETECT		- autodetection in progress
43  * IRQS_SPURIOUS_DISABLED	- was disabled due to spurious interrupt
44  *				  detection
45  * IRQS_POLL_INPROGRESS		- polling in progress
46  * IRQS_ONESHOT			- irq is not unmasked in primary handler
47  * IRQS_REPLAY			- irq is replayed
48  * IRQS_WAITING			- irq is waiting
49  * IRQS_PENDING			- irq is pending and replayed later
50  * IRQS_SUSPENDED		- irq is suspended
51  */
52 enum {
53 	IRQS_AUTODETECT		= 0x00000001,
54 	IRQS_SPURIOUS_DISABLED	= 0x00000002,
55 	IRQS_POLL_INPROGRESS	= 0x00000008,
56 	IRQS_ONESHOT		= 0x00000020,
57 	IRQS_REPLAY		= 0x00000040,
58 	IRQS_WAITING		= 0x00000080,
59 	IRQS_PENDING		= 0x00000200,
60 	IRQS_SUSPENDED		= 0x00000800,
61 	IRQS_TIMINGS		= 0x00001000,
62 };
63 
64 #include "debug.h"
65 #include "settings.h"
66 
67 extern int __irq_set_trigger(struct irq_desc *desc, unsigned long flags);
68 extern void __disable_irq(struct irq_desc *desc);
69 extern void __enable_irq(struct irq_desc *desc);
70 
71 #define IRQ_RESEND	true
72 #define IRQ_NORESEND	false
73 
74 #define IRQ_START_FORCE	true
75 #define IRQ_START_COND	false
76 
77 extern int irq_startup(struct irq_desc *desc, bool resend, bool force);
78 
79 extern void irq_shutdown(struct irq_desc *desc);
80 extern void irq_enable(struct irq_desc *desc);
81 extern void irq_disable(struct irq_desc *desc);
82 extern void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu);
83 extern void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu);
84 extern void mask_irq(struct irq_desc *desc);
85 extern void unmask_irq(struct irq_desc *desc);
86 extern void unmask_threaded_irq(struct irq_desc *desc);
87 
88 #ifdef CONFIG_SPARSE_IRQ
89 static inline void irq_mark_irq(unsigned int irq) { }
90 #else
91 extern void irq_mark_irq(unsigned int irq);
92 #endif
93 
94 extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr);
95 
96 irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags);
97 irqreturn_t handle_irq_event_percpu(struct irq_desc *desc);
98 irqreturn_t handle_irq_event(struct irq_desc *desc);
99 
100 /* Resending of interrupts :*/
101 void check_irq_resend(struct irq_desc *desc);
102 bool irq_wait_for_poll(struct irq_desc *desc);
103 void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
104 
105 #ifdef CONFIG_PROC_FS
106 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
107 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
108 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
109 extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
110 #else
111 static inline void register_irq_proc(unsigned int irq, struct irq_desc *desc) { }
112 static inline void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) { }
113 static inline void register_handler_proc(unsigned int irq,
114 					 struct irqaction *action) { }
115 static inline void unregister_handler_proc(unsigned int irq,
116 					   struct irqaction *action) { }
117 #endif
118 
119 extern bool irq_can_set_affinity_usr(unsigned int irq);
120 
121 extern int irq_select_affinity_usr(unsigned int irq);
122 
123 extern void irq_set_thread_affinity(struct irq_desc *desc);
124 
125 extern int irq_do_set_affinity(struct irq_data *data,
126 			       const struct cpumask *dest, bool force);
127 
128 #ifdef CONFIG_SMP
129 extern int irq_setup_affinity(struct irq_desc *desc);
130 #else
131 static inline int irq_setup_affinity(struct irq_desc *desc) { return 0; }
132 #endif
133 
134 /* Inline functions for support of irq chips on slow busses */
135 static inline void chip_bus_lock(struct irq_desc *desc)
136 {
137 	if (unlikely(desc->irq_data.chip->irq_bus_lock))
138 		desc->irq_data.chip->irq_bus_lock(&desc->irq_data);
139 }
140 
141 static inline void chip_bus_sync_unlock(struct irq_desc *desc)
142 {
143 	if (unlikely(desc->irq_data.chip->irq_bus_sync_unlock))
144 		desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data);
145 }
146 
147 #define _IRQ_DESC_CHECK		(1 << 0)
148 #define _IRQ_DESC_PERCPU	(1 << 1)
149 
150 #define IRQ_GET_DESC_CHECK_GLOBAL	(_IRQ_DESC_CHECK)
151 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
152 
153 #define for_each_action_of_desc(desc, act)			\
154 	for (act = desc->act; act; act = act->next)
155 
156 struct irq_desc *
157 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
158 		    unsigned int check);
159 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus);
160 
161 static inline struct irq_desc *
162 irq_get_desc_buslock(unsigned int irq, unsigned long *flags, unsigned int check)
163 {
164 	return __irq_get_desc_lock(irq, flags, true, check);
165 }
166 
167 static inline void
168 irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags)
169 {
170 	__irq_put_desc_unlock(desc, flags, true);
171 }
172 
173 static inline struct irq_desc *
174 irq_get_desc_lock(unsigned int irq, unsigned long *flags, unsigned int check)
175 {
176 	return __irq_get_desc_lock(irq, flags, false, check);
177 }
178 
179 static inline void
180 irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags)
181 {
182 	__irq_put_desc_unlock(desc, flags, false);
183 }
184 
185 #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
186 
187 static inline unsigned int irqd_get(struct irq_data *d)
188 {
189 	return __irqd_to_state(d);
190 }
191 
192 /*
193  * Manipulation functions for irq_data.state
194  */
195 static inline void irqd_set_move_pending(struct irq_data *d)
196 {
197 	__irqd_to_state(d) |= IRQD_SETAFFINITY_PENDING;
198 }
199 
200 static inline void irqd_clr_move_pending(struct irq_data *d)
201 {
202 	__irqd_to_state(d) &= ~IRQD_SETAFFINITY_PENDING;
203 }
204 
205 static inline void irqd_set_managed_shutdown(struct irq_data *d)
206 {
207 	__irqd_to_state(d) |= IRQD_MANAGED_SHUTDOWN;
208 }
209 
210 static inline void irqd_clr_managed_shutdown(struct irq_data *d)
211 {
212 	__irqd_to_state(d) &= ~IRQD_MANAGED_SHUTDOWN;
213 }
214 
215 static inline void irqd_clear(struct irq_data *d, unsigned int mask)
216 {
217 	__irqd_to_state(d) &= ~mask;
218 }
219 
220 static inline void irqd_set(struct irq_data *d, unsigned int mask)
221 {
222 	__irqd_to_state(d) |= mask;
223 }
224 
225 static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
226 {
227 	return __irqd_to_state(d) & mask;
228 }
229 
230 static inline void irq_state_set_disabled(struct irq_desc *desc)
231 {
232 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
233 }
234 
235 static inline void irq_state_set_masked(struct irq_desc *desc)
236 {
237 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
238 }
239 
240 #undef __irqd_to_state
241 
242 static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
243 {
244 	__this_cpu_inc(*desc->kstat_irqs);
245 	__this_cpu_inc(kstat.irqs_sum);
246 }
247 
248 static inline int irq_desc_get_node(struct irq_desc *desc)
249 {
250 	return irq_common_data_get_node(&desc->irq_common_data);
251 }
252 
253 static inline int irq_desc_is_chained(struct irq_desc *desc)
254 {
255 	return (desc->action && desc->action == &chained_action);
256 }
257 
258 #ifdef CONFIG_PM_SLEEP
259 bool irq_pm_check_wakeup(struct irq_desc *desc);
260 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
261 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
262 #else
263 static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
264 static inline void
265 irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
266 static inline void
267 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
268 #endif
269 
270 #ifdef CONFIG_IRQ_TIMINGS
271 
272 #define IRQ_TIMINGS_SHIFT	5
273 #define IRQ_TIMINGS_SIZE	(1 << IRQ_TIMINGS_SHIFT)
274 #define IRQ_TIMINGS_MASK	(IRQ_TIMINGS_SIZE - 1)
275 
276 /**
277  * struct irq_timings - irq timings storing structure
278  * @values: a circular buffer of u64 encoded <timestamp,irq> values
279  * @count: the number of elements in the array
280  */
281 struct irq_timings {
282 	u64	values[IRQ_TIMINGS_SIZE];
283 	int	count;
284 };
285 
286 DECLARE_PER_CPU(struct irq_timings, irq_timings);
287 
288 extern void irq_timings_free(int irq);
289 extern int irq_timings_alloc(int irq);
290 
291 static inline void irq_remove_timings(struct irq_desc *desc)
292 {
293 	desc->istate &= ~IRQS_TIMINGS;
294 
295 	irq_timings_free(irq_desc_get_irq(desc));
296 }
297 
298 static inline void irq_setup_timings(struct irq_desc *desc, struct irqaction *act)
299 {
300 	int irq = irq_desc_get_irq(desc);
301 	int ret;
302 
303 	/*
304 	 * We don't need the measurement because the idle code already
305 	 * knows the next expiry event.
306 	 */
307 	if (act->flags & __IRQF_TIMER)
308 		return;
309 
310 	/*
311 	 * In case the timing allocation fails, we just want to warn,
312 	 * not fail, so letting the system boot anyway.
313 	 */
314 	ret = irq_timings_alloc(irq);
315 	if (ret) {
316 		pr_warn("Failed to allocate irq timing stats for irq%d (%d)",
317 			irq, ret);
318 		return;
319 	}
320 
321 	desc->istate |= IRQS_TIMINGS;
322 }
323 
324 extern void irq_timings_enable(void);
325 extern void irq_timings_disable(void);
326 
327 DECLARE_STATIC_KEY_FALSE(irq_timing_enabled);
328 
329 /*
330  * The interrupt number and the timestamp are encoded into a single
331  * u64 variable to optimize the size.
332  * 48 bit time stamp and 16 bit IRQ number is way sufficient.
333  *  Who cares an IRQ after 78 hours of idle time?
334  */
335 static inline u64 irq_timing_encode(u64 timestamp, int irq)
336 {
337 	return (timestamp << 16) | irq;
338 }
339 
340 static inline int irq_timing_decode(u64 value, u64 *timestamp)
341 {
342 	*timestamp = value >> 16;
343 	return value & U16_MAX;
344 }
345 
346 /*
347  * The function record_irq_time is only called in one place in the
348  * interrupts handler. We want this function always inline so the code
349  * inside is embedded in the function and the static key branching
350  * code can act at the higher level. Without the explicit
351  * __always_inline we can end up with a function call and a small
352  * overhead in the hotpath for nothing.
353  */
354 static __always_inline void record_irq_time(struct irq_desc *desc)
355 {
356 	if (!static_branch_likely(&irq_timing_enabled))
357 		return;
358 
359 	if (desc->istate & IRQS_TIMINGS) {
360 		struct irq_timings *timings = this_cpu_ptr(&irq_timings);
361 
362 		timings->values[timings->count & IRQ_TIMINGS_MASK] =
363 			irq_timing_encode(local_clock(),
364 					  irq_desc_get_irq(desc));
365 
366 		timings->count++;
367 	}
368 }
369 #else
370 static inline void irq_remove_timings(struct irq_desc *desc) {}
371 static inline void irq_setup_timings(struct irq_desc *desc,
372 				     struct irqaction *act) {};
373 static inline void record_irq_time(struct irq_desc *desc) {}
374 #endif /* CONFIG_IRQ_TIMINGS */
375 
376 
377 #ifdef CONFIG_GENERIC_IRQ_CHIP
378 void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
379 			   int num_ct, unsigned int irq_base,
380 			   void __iomem *reg_base, irq_flow_handler_t handler);
381 #else
382 static inline void
383 irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
384 		      int num_ct, unsigned int irq_base,
385 		      void __iomem *reg_base, irq_flow_handler_t handler) { }
386 #endif /* CONFIG_GENERIC_IRQ_CHIP */
387 
388 #ifdef CONFIG_GENERIC_PENDING_IRQ
389 static inline bool irq_can_move_pcntxt(struct irq_data *data)
390 {
391 	return irqd_can_move_in_process_context(data);
392 }
393 static inline bool irq_move_pending(struct irq_data *data)
394 {
395 	return irqd_is_setaffinity_pending(data);
396 }
397 static inline void
398 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
399 {
400 	cpumask_copy(desc->pending_mask, mask);
401 }
402 static inline void
403 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
404 {
405 	cpumask_copy(mask, desc->pending_mask);
406 }
407 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
408 {
409 	return desc->pending_mask;
410 }
411 bool irq_fixup_move_pending(struct irq_desc *desc, bool force_clear);
412 #else /* CONFIG_GENERIC_PENDING_IRQ */
413 static inline bool irq_can_move_pcntxt(struct irq_data *data)
414 {
415 	return true;
416 }
417 static inline bool irq_move_pending(struct irq_data *data)
418 {
419 	return false;
420 }
421 static inline void
422 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
423 {
424 }
425 static inline void
426 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
427 {
428 }
429 static inline struct cpumask *irq_desc_get_pending_mask(struct irq_desc *desc)
430 {
431 	return NULL;
432 }
433 static inline bool irq_fixup_move_pending(struct irq_desc *desc, bool fclear)
434 {
435 	return false;
436 }
437 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
438 
439 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS
440 #include <linux/debugfs.h>
441 
442 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc);
443 static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
444 {
445 	debugfs_remove(desc->debugfs_file);
446 }
447 # ifdef CONFIG_IRQ_DOMAIN
448 void irq_domain_debugfs_init(struct dentry *root);
449 # else
450 static inline void irq_domain_debugfs_init(struct dentry *root)
451 {
452 }
453 # endif
454 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
455 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)
456 {
457 }
458 static inline void irq_remove_debugfs_entry(struct irq_desc *d)
459 {
460 }
461 #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
462