xref: /linux/kernel/irq/generic-chip.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * Library implementing the most common irq chip callback functions
3  *
4  * Copyright (C) 2011, Thomas Gleixner
5  */
6 #include <linux/io.h>
7 #include <linux/irq.h>
8 #include <linux/slab.h>
9 #include <linux/export.h>
10 #include <linux/interrupt.h>
11 #include <linux/kernel_stat.h>
12 #include <linux/syscore_ops.h>
13 
14 #include "internals.h"
15 
16 static LIST_HEAD(gc_list);
17 static DEFINE_RAW_SPINLOCK(gc_lock);
18 
19 static inline struct irq_chip_regs *cur_regs(struct irq_data *d)
20 {
21 	return &container_of(d->chip, struct irq_chip_type, chip)->regs;
22 }
23 
24 /**
25  * irq_gc_noop - NOOP function
26  * @d: irq_data
27  */
28 void irq_gc_noop(struct irq_data *d)
29 {
30 }
31 
32 /**
33  * irq_gc_mask_disable_reg - Mask chip via disable register
34  * @d: irq_data
35  *
36  * Chip has separate enable/disable registers instead of a single mask
37  * register.
38  */
39 void irq_gc_mask_disable_reg(struct irq_data *d)
40 {
41 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
42 	u32 mask = 1 << (d->irq - gc->irq_base);
43 
44 	irq_gc_lock(gc);
45 	irq_reg_writel(mask, gc->reg_base + cur_regs(d)->disable);
46 	gc->mask_cache &= ~mask;
47 	irq_gc_unlock(gc);
48 }
49 
50 /**
51  * irq_gc_mask_set_mask_bit - Mask chip via setting bit in mask register
52  * @d: irq_data
53  *
54  * Chip has a single mask register. Values of this register are cached
55  * and protected by gc->lock
56  */
57 void irq_gc_mask_set_bit(struct irq_data *d)
58 {
59 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
60 	u32 mask = 1 << (d->irq - gc->irq_base);
61 
62 	irq_gc_lock(gc);
63 	gc->mask_cache |= mask;
64 	irq_reg_writel(gc->mask_cache, gc->reg_base + cur_regs(d)->mask);
65 	irq_gc_unlock(gc);
66 }
67 
68 /**
69  * irq_gc_mask_set_mask_bit - Mask chip via clearing bit in mask register
70  * @d: irq_data
71  *
72  * Chip has a single mask register. Values of this register are cached
73  * and protected by gc->lock
74  */
75 void irq_gc_mask_clr_bit(struct irq_data *d)
76 {
77 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
78 	u32 mask = 1 << (d->irq - gc->irq_base);
79 
80 	irq_gc_lock(gc);
81 	gc->mask_cache &= ~mask;
82 	irq_reg_writel(gc->mask_cache, gc->reg_base + cur_regs(d)->mask);
83 	irq_gc_unlock(gc);
84 }
85 
86 /**
87  * irq_gc_unmask_enable_reg - Unmask chip via enable register
88  * @d: irq_data
89  *
90  * Chip has separate enable/disable registers instead of a single mask
91  * register.
92  */
93 void irq_gc_unmask_enable_reg(struct irq_data *d)
94 {
95 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
96 	u32 mask = 1 << (d->irq - gc->irq_base);
97 
98 	irq_gc_lock(gc);
99 	irq_reg_writel(mask, gc->reg_base + cur_regs(d)->enable);
100 	gc->mask_cache |= mask;
101 	irq_gc_unlock(gc);
102 }
103 
104 /**
105  * irq_gc_ack_set_bit - Ack pending interrupt via setting bit
106  * @d: irq_data
107  */
108 void irq_gc_ack_set_bit(struct irq_data *d)
109 {
110 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
111 	u32 mask = 1 << (d->irq - gc->irq_base);
112 
113 	irq_gc_lock(gc);
114 	irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack);
115 	irq_gc_unlock(gc);
116 }
117 
118 /**
119  * irq_gc_ack_clr_bit - Ack pending interrupt via clearing bit
120  * @d: irq_data
121  */
122 void irq_gc_ack_clr_bit(struct irq_data *d)
123 {
124 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
125 	u32 mask = ~(1 << (d->irq - gc->irq_base));
126 
127 	irq_gc_lock(gc);
128 	irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack);
129 	irq_gc_unlock(gc);
130 }
131 
132 /**
133  * irq_gc_mask_disable_reg_and_ack- Mask and ack pending interrupt
134  * @d: irq_data
135  */
136 void irq_gc_mask_disable_reg_and_ack(struct irq_data *d)
137 {
138 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
139 	u32 mask = 1 << (d->irq - gc->irq_base);
140 
141 	irq_gc_lock(gc);
142 	irq_reg_writel(mask, gc->reg_base + cur_regs(d)->mask);
143 	irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack);
144 	irq_gc_unlock(gc);
145 }
146 
147 /**
148  * irq_gc_eoi - EOI interrupt
149  * @d: irq_data
150  */
151 void irq_gc_eoi(struct irq_data *d)
152 {
153 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
154 	u32 mask = 1 << (d->irq - gc->irq_base);
155 
156 	irq_gc_lock(gc);
157 	irq_reg_writel(mask, gc->reg_base + cur_regs(d)->eoi);
158 	irq_gc_unlock(gc);
159 }
160 
161 /**
162  * irq_gc_set_wake - Set/clr wake bit for an interrupt
163  * @d: irq_data
164  *
165  * For chips where the wake from suspend functionality is not
166  * configured in a separate register and the wakeup active state is
167  * just stored in a bitmask.
168  */
169 int irq_gc_set_wake(struct irq_data *d, unsigned int on)
170 {
171 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
172 	u32 mask = 1 << (d->irq - gc->irq_base);
173 
174 	if (!(mask & gc->wake_enabled))
175 		return -EINVAL;
176 
177 	irq_gc_lock(gc);
178 	if (on)
179 		gc->wake_active |= mask;
180 	else
181 		gc->wake_active &= ~mask;
182 	irq_gc_unlock(gc);
183 	return 0;
184 }
185 
186 /**
187  * irq_alloc_generic_chip - Allocate a generic chip and initialize it
188  * @name:	Name of the irq chip
189  * @num_ct:	Number of irq_chip_type instances associated with this
190  * @irq_base:	Interrupt base nr for this chip
191  * @reg_base:	Register base address (virtual)
192  * @handler:	Default flow handler associated with this chip
193  *
194  * Returns an initialized irq_chip_generic structure. The chip defaults
195  * to the primary (index 0) irq_chip_type and @handler
196  */
197 struct irq_chip_generic *
198 irq_alloc_generic_chip(const char *name, int num_ct, unsigned int irq_base,
199 		       void __iomem *reg_base, irq_flow_handler_t handler)
200 {
201 	struct irq_chip_generic *gc;
202 	unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
203 
204 	gc = kzalloc(sz, GFP_KERNEL);
205 	if (gc) {
206 		raw_spin_lock_init(&gc->lock);
207 		gc->num_ct = num_ct;
208 		gc->irq_base = irq_base;
209 		gc->reg_base = reg_base;
210 		gc->chip_types->chip.name = name;
211 		gc->chip_types->handler = handler;
212 	}
213 	return gc;
214 }
215 EXPORT_SYMBOL_GPL(irq_alloc_generic_chip);
216 
217 /*
218  * Separate lockdep class for interrupt chip which can nest irq_desc
219  * lock.
220  */
221 static struct lock_class_key irq_nested_lock_class;
222 
223 /**
224  * irq_setup_generic_chip - Setup a range of interrupts with a generic chip
225  * @gc:		Generic irq chip holding all data
226  * @msk:	Bitmask holding the irqs to initialize relative to gc->irq_base
227  * @flags:	Flags for initialization
228  * @clr:	IRQ_* bits to clear
229  * @set:	IRQ_* bits to set
230  *
231  * Set up max. 32 interrupts starting from gc->irq_base. Note, this
232  * initializes all interrupts to the primary irq_chip_type and its
233  * associated handler.
234  */
235 void irq_setup_generic_chip(struct irq_chip_generic *gc, u32 msk,
236 			    enum irq_gc_flags flags, unsigned int clr,
237 			    unsigned int set)
238 {
239 	struct irq_chip_type *ct = gc->chip_types;
240 	unsigned int i;
241 
242 	raw_spin_lock(&gc_lock);
243 	list_add_tail(&gc->list, &gc_list);
244 	raw_spin_unlock(&gc_lock);
245 
246 	/* Init mask cache ? */
247 	if (flags & IRQ_GC_INIT_MASK_CACHE)
248 		gc->mask_cache = irq_reg_readl(gc->reg_base + ct->regs.mask);
249 
250 	for (i = gc->irq_base; msk; msk >>= 1, i++) {
251 		if (!(msk & 0x01))
252 			continue;
253 
254 		if (flags & IRQ_GC_INIT_NESTED_LOCK)
255 			irq_set_lockdep_class(i, &irq_nested_lock_class);
256 
257 		irq_set_chip_and_handler(i, &ct->chip, ct->handler);
258 		irq_set_chip_data(i, gc);
259 		irq_modify_status(i, clr, set);
260 	}
261 	gc->irq_cnt = i - gc->irq_base;
262 }
263 EXPORT_SYMBOL_GPL(irq_setup_generic_chip);
264 
265 /**
266  * irq_setup_alt_chip - Switch to alternative chip
267  * @d:		irq_data for this interrupt
268  * @type	Flow type to be initialized
269  *
270  * Only to be called from chip->irq_set_type() callbacks.
271  */
272 int irq_setup_alt_chip(struct irq_data *d, unsigned int type)
273 {
274 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
275 	struct irq_chip_type *ct = gc->chip_types;
276 	unsigned int i;
277 
278 	for (i = 0; i < gc->num_ct; i++, ct++) {
279 		if (ct->type & type) {
280 			d->chip = &ct->chip;
281 			irq_data_to_desc(d)->handle_irq = ct->handler;
282 			return 0;
283 		}
284 	}
285 	return -EINVAL;
286 }
287 EXPORT_SYMBOL_GPL(irq_setup_alt_chip);
288 
289 /**
290  * irq_remove_generic_chip - Remove a chip
291  * @gc:		Generic irq chip holding all data
292  * @msk:	Bitmask holding the irqs to initialize relative to gc->irq_base
293  * @clr:	IRQ_* bits to clear
294  * @set:	IRQ_* bits to set
295  *
296  * Remove up to 32 interrupts starting from gc->irq_base.
297  */
298 void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk,
299 			     unsigned int clr, unsigned int set)
300 {
301 	unsigned int i = gc->irq_base;
302 
303 	raw_spin_lock(&gc_lock);
304 	list_del(&gc->list);
305 	raw_spin_unlock(&gc_lock);
306 
307 	for (; msk; msk >>= 1, i++) {
308 		if (!(msk & 0x01))
309 			continue;
310 
311 		/* Remove handler first. That will mask the irq line */
312 		irq_set_handler(i, NULL);
313 		irq_set_chip(i, &no_irq_chip);
314 		irq_set_chip_data(i, NULL);
315 		irq_modify_status(i, clr, set);
316 	}
317 }
318 EXPORT_SYMBOL_GPL(irq_remove_generic_chip);
319 
320 #ifdef CONFIG_PM
321 static int irq_gc_suspend(void)
322 {
323 	struct irq_chip_generic *gc;
324 
325 	list_for_each_entry(gc, &gc_list, list) {
326 		struct irq_chip_type *ct = gc->chip_types;
327 
328 		if (ct->chip.irq_suspend)
329 			ct->chip.irq_suspend(irq_get_irq_data(gc->irq_base));
330 	}
331 	return 0;
332 }
333 
334 static void irq_gc_resume(void)
335 {
336 	struct irq_chip_generic *gc;
337 
338 	list_for_each_entry(gc, &gc_list, list) {
339 		struct irq_chip_type *ct = gc->chip_types;
340 
341 		if (ct->chip.irq_resume)
342 			ct->chip.irq_resume(irq_get_irq_data(gc->irq_base));
343 	}
344 }
345 #else
346 #define irq_gc_suspend NULL
347 #define irq_gc_resume NULL
348 #endif
349 
350 static void irq_gc_shutdown(void)
351 {
352 	struct irq_chip_generic *gc;
353 
354 	list_for_each_entry(gc, &gc_list, list) {
355 		struct irq_chip_type *ct = gc->chip_types;
356 
357 		if (ct->chip.irq_pm_shutdown)
358 			ct->chip.irq_pm_shutdown(irq_get_irq_data(gc->irq_base));
359 	}
360 }
361 
362 static struct syscore_ops irq_gc_syscore_ops = {
363 	.suspend = irq_gc_suspend,
364 	.resume = irq_gc_resume,
365 	.shutdown = irq_gc_shutdown,
366 };
367 
368 static int __init irq_gc_init_ops(void)
369 {
370 	register_syscore_ops(&irq_gc_syscore_ops);
371 	return 0;
372 }
373 device_initcall(irq_gc_init_ops);
374