xref: /openbmc/linux/drivers/sh/intc/core.c (revision 37b9b9a5)
1 /*
2  * Shared interrupt handling code for IPR and INTC2 types of IRQs.
3  *
4  * Copyright (C) 2007, 2008 Magnus Damm
5  * Copyright (C) 2009 - 2012 Paul Mundt
6  *
7  * Based on intc2.c and ipr.c
8  *
9  * Copyright (C) 1999  Niibe Yutaka & Takeshi Yaegashi
10  * Copyright (C) 2000  Kazumoto Kojima
11  * Copyright (C) 2001  David J. Mckay (david.mckay@st.com)
12  * Copyright (C) 2003  Takashi Kusuda <kusuda-takashi@hitachi-ul.co.jp>
13  * Copyright (C) 2005, 2006  Paul Mundt
14  *
15  * This file is subject to the terms and conditions of the GNU General Public
16  * License.  See the file "COPYING" in the main directory of this archive
17  * for more details.
18  */
19 #define pr_fmt(fmt) "intc: " fmt
20 
21 #include <linux/init.h>
22 #include <linux/irq.h>
23 #include <linux/io.h>
24 #include <linux/slab.h>
25 #include <linux/stat.h>
26 #include <linux/interrupt.h>
27 #include <linux/sh_intc.h>
28 #include <linux/irqdomain.h>
29 #include <linux/device.h>
30 #include <linux/syscore_ops.h>
31 #include <linux/list.h>
32 #include <linux/spinlock.h>
33 #include <linux/radix-tree.h>
34 #include <linux/export.h>
35 #include <linux/sort.h>
36 #include "internals.h"
37 
38 LIST_HEAD(intc_list);
39 DEFINE_RAW_SPINLOCK(intc_big_lock);
40 static unsigned int nr_intc_controllers;
41 
42 /*
43  * Default priority level
44  * - this needs to be at least 2 for 5-bit priorities on 7780
45  */
46 static unsigned int default_prio_level = 2;	/* 2 - 16 */
47 static unsigned int intc_prio_level[INTC_NR_IRQS];	/* for now */
48 
49 unsigned int intc_get_dfl_prio_level(void)
50 {
51 	return default_prio_level;
52 }
53 
54 unsigned int intc_get_prio_level(unsigned int irq)
55 {
56 	return intc_prio_level[irq];
57 }
58 
59 void intc_set_prio_level(unsigned int irq, unsigned int level)
60 {
61 	unsigned long flags;
62 
63 	raw_spin_lock_irqsave(&intc_big_lock, flags);
64 	intc_prio_level[irq] = level;
65 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
66 }
67 
68 static void intc_redirect_irq(struct irq_desc *desc)
69 {
70 	generic_handle_irq((unsigned int)irq_desc_get_handler_data(desc));
71 }
72 
73 static void __init intc_register_irq(struct intc_desc *desc,
74 				     struct intc_desc_int *d,
75 				     intc_enum enum_id,
76 				     unsigned int irq)
77 {
78 	struct intc_handle_int *hp;
79 	struct irq_data *irq_data;
80 	unsigned int data[2], primary;
81 	unsigned long flags;
82 
83 	raw_spin_lock_irqsave(&intc_big_lock, flags);
84 	radix_tree_insert(&d->tree, enum_id, intc_irq_xlate_get(irq));
85 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
86 
87 	/*
88 	 * Prefer single interrupt source bitmap over other combinations:
89 	 *
90 	 * 1. bitmap, single interrupt source
91 	 * 2. priority, single interrupt source
92 	 * 3. bitmap, multiple interrupt sources (groups)
93 	 * 4. priority, multiple interrupt sources (groups)
94 	 */
95 	data[0] = intc_get_mask_handle(desc, d, enum_id, 0);
96 	data[1] = intc_get_prio_handle(desc, d, enum_id, 0);
97 
98 	primary = 0;
99 	if (!data[0] && data[1])
100 		primary = 1;
101 
102 	if (!data[0] && !data[1])
103 		pr_warn("missing unique irq mask for irq %d (vect 0x%04x)\n",
104 			irq, irq2evt(irq));
105 
106 	data[0] = data[0] ? data[0] : intc_get_mask_handle(desc, d, enum_id, 1);
107 	data[1] = data[1] ? data[1] : intc_get_prio_handle(desc, d, enum_id, 1);
108 
109 	if (!data[primary])
110 		primary ^= 1;
111 
112 	BUG_ON(!data[primary]); /* must have primary masking method */
113 
114 	irq_data = irq_get_irq_data(irq);
115 
116 	disable_irq_nosync(irq);
117 	irq_set_chip_and_handler_name(irq, &d->chip, handle_level_irq,
118 				      "level");
119 	irq_set_chip_data(irq, (void *)data[primary]);
120 
121 	/*
122 	 * set priority level
123 	 */
124 	intc_set_prio_level(irq, intc_get_dfl_prio_level());
125 
126 	/* enable secondary masking method if present */
127 	if (data[!primary])
128 		_intc_enable(irq_data, data[!primary]);
129 
130 	/* add irq to d->prio list if priority is available */
131 	if (data[1]) {
132 		hp = d->prio + d->nr_prio;
133 		hp->irq = irq;
134 		hp->handle = data[1];
135 
136 		if (primary) {
137 			/*
138 			 * only secondary priority should access registers, so
139 			 * set _INTC_FN(h) = REG_FN_ERR for intc_set_priority()
140 			 */
141 			hp->handle &= ~_INTC_MK(0x0f, 0, 0, 0, 0, 0);
142 			hp->handle |= _INTC_MK(REG_FN_ERR, 0, 0, 0, 0, 0);
143 		}
144 		d->nr_prio++;
145 	}
146 
147 	/* add irq to d->sense list if sense is available */
148 	data[0] = intc_get_sense_handle(desc, d, enum_id);
149 	if (data[0]) {
150 		(d->sense + d->nr_sense)->irq = irq;
151 		(d->sense + d->nr_sense)->handle = data[0];
152 		d->nr_sense++;
153 	}
154 
155 	/* irq should be disabled by default */
156 	d->chip.irq_mask(irq_data);
157 
158 	intc_set_ack_handle(irq, desc, d, enum_id);
159 	intc_set_dist_handle(irq, desc, d, enum_id);
160 
161 	activate_irq(irq);
162 }
163 
164 static unsigned int __init save_reg(struct intc_desc_int *d,
165 				    unsigned int cnt,
166 				    unsigned long value,
167 				    unsigned int smp)
168 {
169 	if (value) {
170 		value = intc_phys_to_virt(d, value);
171 
172 		d->reg[cnt] = value;
173 #ifdef CONFIG_SMP
174 		d->smp[cnt] = smp;
175 #endif
176 		return 1;
177 	}
178 
179 	return 0;
180 }
181 
182 int __init register_intc_controller(struct intc_desc *desc)
183 {
184 	unsigned int i, k, smp;
185 	struct intc_hw_desc *hw = &desc->hw;
186 	struct intc_desc_int *d;
187 	struct resource *res;
188 
189 	pr_info("Registered controller '%s' with %u IRQs\n",
190 		desc->name, hw->nr_vectors);
191 
192 	d = kzalloc(sizeof(*d), GFP_NOWAIT);
193 	if (!d)
194 		goto err0;
195 
196 	INIT_LIST_HEAD(&d->list);
197 	list_add_tail(&d->list, &intc_list);
198 
199 	raw_spin_lock_init(&d->lock);
200 	INIT_RADIX_TREE(&d->tree, GFP_ATOMIC);
201 
202 	d->index = nr_intc_controllers;
203 
204 	if (desc->num_resources) {
205 		d->nr_windows = desc->num_resources;
206 		d->window = kcalloc(d->nr_windows, sizeof(*d->window),
207 				    GFP_NOWAIT);
208 		if (!d->window)
209 			goto err1;
210 
211 		for (k = 0; k < d->nr_windows; k++) {
212 			res = desc->resource + k;
213 			WARN_ON(resource_type(res) != IORESOURCE_MEM);
214 			d->window[k].phys = res->start;
215 			d->window[k].size = resource_size(res);
216 			d->window[k].virt = ioremap_nocache(res->start,
217 							 resource_size(res));
218 			if (!d->window[k].virt)
219 				goto err2;
220 		}
221 	}
222 
223 	d->nr_reg = hw->mask_regs ? hw->nr_mask_regs * 2 : 0;
224 #ifdef CONFIG_INTC_BALANCING
225 	if (d->nr_reg)
226 		d->nr_reg += hw->nr_mask_regs;
227 #endif
228 	d->nr_reg += hw->prio_regs ? hw->nr_prio_regs * 2 : 0;
229 	d->nr_reg += hw->sense_regs ? hw->nr_sense_regs : 0;
230 	d->nr_reg += hw->ack_regs ? hw->nr_ack_regs : 0;
231 	d->nr_reg += hw->subgroups ? hw->nr_subgroups : 0;
232 
233 	d->reg = kcalloc(d->nr_reg, sizeof(*d->reg), GFP_NOWAIT);
234 	if (!d->reg)
235 		goto err2;
236 
237 #ifdef CONFIG_SMP
238 	d->smp = kcalloc(d->nr_reg, sizeof(*d->smp), GFP_NOWAIT);
239 	if (!d->smp)
240 		goto err3;
241 #endif
242 	k = 0;
243 
244 	if (hw->mask_regs) {
245 		for (i = 0; i < hw->nr_mask_regs; i++) {
246 			smp = IS_SMP(hw->mask_regs[i]);
247 			k += save_reg(d, k, hw->mask_regs[i].set_reg, smp);
248 			k += save_reg(d, k, hw->mask_regs[i].clr_reg, smp);
249 #ifdef CONFIG_INTC_BALANCING
250 			k += save_reg(d, k, hw->mask_regs[i].dist_reg, 0);
251 #endif
252 		}
253 	}
254 
255 	if (hw->prio_regs) {
256 		d->prio = kcalloc(hw->nr_vectors, sizeof(*d->prio),
257 				  GFP_NOWAIT);
258 		if (!d->prio)
259 			goto err4;
260 
261 		for (i = 0; i < hw->nr_prio_regs; i++) {
262 			smp = IS_SMP(hw->prio_regs[i]);
263 			k += save_reg(d, k, hw->prio_regs[i].set_reg, smp);
264 			k += save_reg(d, k, hw->prio_regs[i].clr_reg, smp);
265 		}
266 
267 		sort(d->prio, hw->nr_prio_regs, sizeof(*d->prio),
268 		     intc_handle_int_cmp, NULL);
269 	}
270 
271 	if (hw->sense_regs) {
272 		d->sense = kcalloc(hw->nr_vectors, sizeof(*d->sense),
273 				   GFP_NOWAIT);
274 		if (!d->sense)
275 			goto err5;
276 
277 		for (i = 0; i < hw->nr_sense_regs; i++)
278 			k += save_reg(d, k, hw->sense_regs[i].reg, 0);
279 
280 		sort(d->sense, hw->nr_sense_regs, sizeof(*d->sense),
281 		     intc_handle_int_cmp, NULL);
282 	}
283 
284 	if (hw->subgroups)
285 		for (i = 0; i < hw->nr_subgroups; i++)
286 			if (hw->subgroups[i].reg)
287 				k+= save_reg(d, k, hw->subgroups[i].reg, 0);
288 
289 	memcpy(&d->chip, &intc_irq_chip, sizeof(struct irq_chip));
290 	d->chip.name = desc->name;
291 
292 	if (hw->ack_regs)
293 		for (i = 0; i < hw->nr_ack_regs; i++)
294 			k += save_reg(d, k, hw->ack_regs[i].set_reg, 0);
295 	else
296 		d->chip.irq_mask_ack = d->chip.irq_disable;
297 
298 	/* disable bits matching force_disable before registering irqs */
299 	if (desc->force_disable)
300 		intc_enable_disable_enum(desc, d, desc->force_disable, 0);
301 
302 	/* disable bits matching force_enable before registering irqs */
303 	if (desc->force_enable)
304 		intc_enable_disable_enum(desc, d, desc->force_enable, 0);
305 
306 	BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
307 
308 	intc_irq_domain_init(d, hw);
309 
310 	/* register the vectors one by one */
311 	for (i = 0; i < hw->nr_vectors; i++) {
312 		struct intc_vect *vect = hw->vectors + i;
313 		unsigned int irq = evt2irq(vect->vect);
314 		int res;
315 
316 		if (!vect->enum_id)
317 			continue;
318 
319 		res = irq_create_identity_mapping(d->domain, irq);
320 		if (unlikely(res)) {
321 			if (res == -EEXIST) {
322 				res = irq_domain_associate(d->domain, irq, irq);
323 				if (unlikely(res)) {
324 					pr_err("domain association failure\n");
325 					continue;
326 				}
327 			} else {
328 				pr_err("can't identity map IRQ %d\n", irq);
329 				continue;
330 			}
331 		}
332 
333 		intc_irq_xlate_set(irq, vect->enum_id, d);
334 		intc_register_irq(desc, d, vect->enum_id, irq);
335 
336 		for (k = i + 1; k < hw->nr_vectors; k++) {
337 			struct intc_vect *vect2 = hw->vectors + k;
338 			unsigned int irq2 = evt2irq(vect2->vect);
339 
340 			if (vect->enum_id != vect2->enum_id)
341 				continue;
342 
343 			/*
344 			 * In the case of multi-evt handling and sparse
345 			 * IRQ support, each vector still needs to have
346 			 * its own backing irq_desc.
347 			 */
348 			res = irq_create_identity_mapping(d->domain, irq2);
349 			if (unlikely(res)) {
350 				if (res == -EEXIST) {
351 					res = irq_domain_associate(d->domain,
352 								   irq2, irq2);
353 					if (unlikely(res)) {
354 						pr_err("domain association "
355 						       "failure\n");
356 						continue;
357 					}
358 				} else {
359 					pr_err("can't identity map IRQ %d\n",
360 					       irq);
361 					continue;
362 				}
363 			}
364 
365 			vect2->enum_id = 0;
366 
367 			/* redirect this interrupts to the first one */
368 			irq_set_chip(irq2, &dummy_irq_chip);
369 			irq_set_chained_handler_and_data(irq2,
370 							 intc_redirect_irq,
371 							 (void *)irq);
372 		}
373 	}
374 
375 	intc_subgroup_init(desc, d);
376 
377 	/* enable bits matching force_enable after registering irqs */
378 	if (desc->force_enable)
379 		intc_enable_disable_enum(desc, d, desc->force_enable, 1);
380 
381 	d->skip_suspend = desc->skip_syscore_suspend;
382 
383 	nr_intc_controllers++;
384 
385 	return 0;
386 err5:
387 	kfree(d->prio);
388 err4:
389 #ifdef CONFIG_SMP
390 	kfree(d->smp);
391 err3:
392 #endif
393 	kfree(d->reg);
394 err2:
395 	for (k = 0; k < d->nr_windows; k++)
396 		if (d->window[k].virt)
397 			iounmap(d->window[k].virt);
398 
399 	kfree(d->window);
400 err1:
401 	kfree(d);
402 err0:
403 	pr_err("unable to allocate INTC memory\n");
404 
405 	return -ENOMEM;
406 }
407 
408 static int intc_suspend(void)
409 {
410 	struct intc_desc_int *d;
411 
412 	list_for_each_entry(d, &intc_list, list) {
413 		int irq;
414 
415 		if (d->skip_suspend)
416 			continue;
417 
418 		/* enable wakeup irqs belonging to this intc controller */
419 		for_each_active_irq(irq) {
420 			struct irq_data *data;
421 			struct irq_chip *chip;
422 
423 			data = irq_get_irq_data(irq);
424 			chip = irq_data_get_irq_chip(data);
425 			if (chip != &d->chip)
426 				continue;
427 			if (irqd_is_wakeup_set(data))
428 				chip->irq_enable(data);
429 		}
430 	}
431 	return 0;
432 }
433 
434 static void intc_resume(void)
435 {
436 	struct intc_desc_int *d;
437 
438 	list_for_each_entry(d, &intc_list, list) {
439 		int irq;
440 
441 		if (d->skip_suspend)
442 			continue;
443 
444 		for_each_active_irq(irq) {
445 			struct irq_data *data;
446 			struct irq_chip *chip;
447 
448 			data = irq_get_irq_data(irq);
449 			chip = irq_data_get_irq_chip(data);
450 			/*
451 			 * This will catch the redirect and VIRQ cases
452 			 * due to the dummy_irq_chip being inserted.
453 			 */
454 			if (chip != &d->chip)
455 				continue;
456 			if (irqd_irq_disabled(data))
457 				chip->irq_disable(data);
458 			else
459 				chip->irq_enable(data);
460 		}
461 	}
462 }
463 
464 struct syscore_ops intc_syscore_ops = {
465 	.suspend	= intc_suspend,
466 	.resume		= intc_resume,
467 };
468 
469 struct bus_type intc_subsys = {
470 	.name		= "intc",
471 	.dev_name	= "intc",
472 };
473 
474 static ssize_t
475 show_intc_name(struct device *dev, struct device_attribute *attr, char *buf)
476 {
477 	struct intc_desc_int *d;
478 
479 	d = container_of(dev, struct intc_desc_int, dev);
480 
481 	return sprintf(buf, "%s\n", d->chip.name);
482 }
483 
484 static DEVICE_ATTR(name, S_IRUGO, show_intc_name, NULL);
485 
486 static int __init register_intc_devs(void)
487 {
488 	struct intc_desc_int *d;
489 	int error;
490 
491 	register_syscore_ops(&intc_syscore_ops);
492 
493 	error = subsys_system_register(&intc_subsys, NULL);
494 	if (!error) {
495 		list_for_each_entry(d, &intc_list, list) {
496 			d->dev.id = d->index;
497 			d->dev.bus = &intc_subsys;
498 			error = device_register(&d->dev);
499 			if (error == 0)
500 				error = device_create_file(&d->dev,
501 							   &dev_attr_name);
502 			if (error)
503 				break;
504 		}
505 	}
506 
507 	if (error)
508 		pr_err("device registration error\n");
509 
510 	return error;
511 }
512 device_initcall(register_intc_devs);
513