xref: /openbmc/linux/drivers/sh/intc/core.c (revision 95e9fd10)
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(unsigned int irq, struct irq_desc *desc)
69 {
70 	generic_handle_irq((unsigned int)irq_get_handler_data(irq));
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 	/*
84 	 * Register the IRQ position with the global IRQ map, then insert
85 	 * it in to the radix tree.
86 	 */
87 	irq_reserve_irq(irq);
88 
89 	raw_spin_lock_irqsave(&intc_big_lock, flags);
90 	radix_tree_insert(&d->tree, enum_id, intc_irq_xlate_get(irq));
91 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
92 
93 	/*
94 	 * Prefer single interrupt source bitmap over other combinations:
95 	 *
96 	 * 1. bitmap, single interrupt source
97 	 * 2. priority, single interrupt source
98 	 * 3. bitmap, multiple interrupt sources (groups)
99 	 * 4. priority, multiple interrupt sources (groups)
100 	 */
101 	data[0] = intc_get_mask_handle(desc, d, enum_id, 0);
102 	data[1] = intc_get_prio_handle(desc, d, enum_id, 0);
103 
104 	primary = 0;
105 	if (!data[0] && data[1])
106 		primary = 1;
107 
108 	if (!data[0] && !data[1])
109 		pr_warning("missing unique irq mask for irq %d (vect 0x%04x)\n",
110 			   irq, irq2evt(irq));
111 
112 	data[0] = data[0] ? data[0] : intc_get_mask_handle(desc, d, enum_id, 1);
113 	data[1] = data[1] ? data[1] : intc_get_prio_handle(desc, d, enum_id, 1);
114 
115 	if (!data[primary])
116 		primary ^= 1;
117 
118 	BUG_ON(!data[primary]); /* must have primary masking method */
119 
120 	irq_data = irq_get_irq_data(irq);
121 
122 	disable_irq_nosync(irq);
123 	irq_set_chip_and_handler_name(irq, &d->chip, handle_level_irq,
124 				      "level");
125 	irq_set_chip_data(irq, (void *)data[primary]);
126 
127 	/*
128 	 * set priority level
129 	 */
130 	intc_set_prio_level(irq, intc_get_dfl_prio_level());
131 
132 	/* enable secondary masking method if present */
133 	if (data[!primary])
134 		_intc_enable(irq_data, data[!primary]);
135 
136 	/* add irq to d->prio list if priority is available */
137 	if (data[1]) {
138 		hp = d->prio + d->nr_prio;
139 		hp->irq = irq;
140 		hp->handle = data[1];
141 
142 		if (primary) {
143 			/*
144 			 * only secondary priority should access registers, so
145 			 * set _INTC_FN(h) = REG_FN_ERR for intc_set_priority()
146 			 */
147 			hp->handle &= ~_INTC_MK(0x0f, 0, 0, 0, 0, 0);
148 			hp->handle |= _INTC_MK(REG_FN_ERR, 0, 0, 0, 0, 0);
149 		}
150 		d->nr_prio++;
151 	}
152 
153 	/* add irq to d->sense list if sense is available */
154 	data[0] = intc_get_sense_handle(desc, d, enum_id);
155 	if (data[0]) {
156 		(d->sense + d->nr_sense)->irq = irq;
157 		(d->sense + d->nr_sense)->handle = data[0];
158 		d->nr_sense++;
159 	}
160 
161 	/* irq should be disabled by default */
162 	d->chip.irq_mask(irq_data);
163 
164 	intc_set_ack_handle(irq, desc, d, enum_id);
165 	intc_set_dist_handle(irq, desc, d, enum_id);
166 
167 	activate_irq(irq);
168 }
169 
170 static unsigned int __init save_reg(struct intc_desc_int *d,
171 				    unsigned int cnt,
172 				    unsigned long value,
173 				    unsigned int smp)
174 {
175 	if (value) {
176 		value = intc_phys_to_virt(d, value);
177 
178 		d->reg[cnt] = value;
179 #ifdef CONFIG_SMP
180 		d->smp[cnt] = smp;
181 #endif
182 		return 1;
183 	}
184 
185 	return 0;
186 }
187 
188 int __init register_intc_controller(struct intc_desc *desc)
189 {
190 	unsigned int i, k, smp;
191 	struct intc_hw_desc *hw = &desc->hw;
192 	struct intc_desc_int *d;
193 	struct resource *res;
194 
195 	pr_info("Registered controller '%s' with %u IRQs\n",
196 		desc->name, hw->nr_vectors);
197 
198 	d = kzalloc(sizeof(*d), GFP_NOWAIT);
199 	if (!d)
200 		goto err0;
201 
202 	INIT_LIST_HEAD(&d->list);
203 	list_add_tail(&d->list, &intc_list);
204 
205 	raw_spin_lock_init(&d->lock);
206 	INIT_RADIX_TREE(&d->tree, GFP_ATOMIC);
207 
208 	d->index = nr_intc_controllers;
209 
210 	if (desc->num_resources) {
211 		d->nr_windows = desc->num_resources;
212 		d->window = kzalloc(d->nr_windows * sizeof(*d->window),
213 				    GFP_NOWAIT);
214 		if (!d->window)
215 			goto err1;
216 
217 		for (k = 0; k < d->nr_windows; k++) {
218 			res = desc->resource + k;
219 			WARN_ON(resource_type(res) != IORESOURCE_MEM);
220 			d->window[k].phys = res->start;
221 			d->window[k].size = resource_size(res);
222 			d->window[k].virt = ioremap_nocache(res->start,
223 							 resource_size(res));
224 			if (!d->window[k].virt)
225 				goto err2;
226 		}
227 	}
228 
229 	d->nr_reg = hw->mask_regs ? hw->nr_mask_regs * 2 : 0;
230 #ifdef CONFIG_INTC_BALANCING
231 	if (d->nr_reg)
232 		d->nr_reg += hw->nr_mask_regs;
233 #endif
234 	d->nr_reg += hw->prio_regs ? hw->nr_prio_regs * 2 : 0;
235 	d->nr_reg += hw->sense_regs ? hw->nr_sense_regs : 0;
236 	d->nr_reg += hw->ack_regs ? hw->nr_ack_regs : 0;
237 	d->nr_reg += hw->subgroups ? hw->nr_subgroups : 0;
238 
239 	d->reg = kzalloc(d->nr_reg * sizeof(*d->reg), GFP_NOWAIT);
240 	if (!d->reg)
241 		goto err2;
242 
243 #ifdef CONFIG_SMP
244 	d->smp = kzalloc(d->nr_reg * sizeof(*d->smp), GFP_NOWAIT);
245 	if (!d->smp)
246 		goto err3;
247 #endif
248 	k = 0;
249 
250 	if (hw->mask_regs) {
251 		for (i = 0; i < hw->nr_mask_regs; i++) {
252 			smp = IS_SMP(hw->mask_regs[i]);
253 			k += save_reg(d, k, hw->mask_regs[i].set_reg, smp);
254 			k += save_reg(d, k, hw->mask_regs[i].clr_reg, smp);
255 #ifdef CONFIG_INTC_BALANCING
256 			k += save_reg(d, k, hw->mask_regs[i].dist_reg, 0);
257 #endif
258 		}
259 	}
260 
261 	if (hw->prio_regs) {
262 		d->prio = kzalloc(hw->nr_vectors * sizeof(*d->prio),
263 				  GFP_NOWAIT);
264 		if (!d->prio)
265 			goto err4;
266 
267 		for (i = 0; i < hw->nr_prio_regs; i++) {
268 			smp = IS_SMP(hw->prio_regs[i]);
269 			k += save_reg(d, k, hw->prio_regs[i].set_reg, smp);
270 			k += save_reg(d, k, hw->prio_regs[i].clr_reg, smp);
271 		}
272 
273 		sort(d->prio, hw->nr_prio_regs, sizeof(*d->prio),
274 		     intc_handle_int_cmp, NULL);
275 	}
276 
277 	if (hw->sense_regs) {
278 		d->sense = kzalloc(hw->nr_vectors * sizeof(*d->sense),
279 				   GFP_NOWAIT);
280 		if (!d->sense)
281 			goto err5;
282 
283 		for (i = 0; i < hw->nr_sense_regs; i++)
284 			k += save_reg(d, k, hw->sense_regs[i].reg, 0);
285 
286 		sort(d->sense, hw->nr_sense_regs, sizeof(*d->sense),
287 		     intc_handle_int_cmp, NULL);
288 	}
289 
290 	if (hw->subgroups)
291 		for (i = 0; i < hw->nr_subgroups; i++)
292 			if (hw->subgroups[i].reg)
293 				k+= save_reg(d, k, hw->subgroups[i].reg, 0);
294 
295 	memcpy(&d->chip, &intc_irq_chip, sizeof(struct irq_chip));
296 	d->chip.name = desc->name;
297 
298 	if (hw->ack_regs)
299 		for (i = 0; i < hw->nr_ack_regs; i++)
300 			k += save_reg(d, k, hw->ack_regs[i].set_reg, 0);
301 	else
302 		d->chip.irq_mask_ack = d->chip.irq_disable;
303 
304 	/* disable bits matching force_disable before registering irqs */
305 	if (desc->force_disable)
306 		intc_enable_disable_enum(desc, d, desc->force_disable, 0);
307 
308 	/* disable bits matching force_enable before registering irqs */
309 	if (desc->force_enable)
310 		intc_enable_disable_enum(desc, d, desc->force_enable, 0);
311 
312 	BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
313 
314 	intc_irq_domain_init(d, hw);
315 
316 	/* register the vectors one by one */
317 	for (i = 0; i < hw->nr_vectors; i++) {
318 		struct intc_vect *vect = hw->vectors + i;
319 		unsigned int irq = evt2irq(vect->vect);
320 		int res;
321 
322 		if (!vect->enum_id)
323 			continue;
324 
325 		res = irq_create_identity_mapping(d->domain, irq);
326 		if (unlikely(res)) {
327 			if (res == -EEXIST) {
328 				res = irq_domain_associate(d->domain, irq, irq);
329 				if (unlikely(res)) {
330 					pr_err("domain association failure\n");
331 					continue;
332 				}
333 			} else {
334 				pr_err("can't identity map IRQ %d\n", irq);
335 				continue;
336 			}
337 		}
338 
339 		intc_irq_xlate_set(irq, vect->enum_id, d);
340 		intc_register_irq(desc, d, vect->enum_id, irq);
341 
342 		for (k = i + 1; k < hw->nr_vectors; k++) {
343 			struct intc_vect *vect2 = hw->vectors + k;
344 			unsigned int irq2 = evt2irq(vect2->vect);
345 
346 			if (vect->enum_id != vect2->enum_id)
347 				continue;
348 
349 			/*
350 			 * In the case of multi-evt handling and sparse
351 			 * IRQ support, each vector still needs to have
352 			 * its own backing irq_desc.
353 			 */
354 			res = irq_create_identity_mapping(d->domain, irq2);
355 			if (unlikely(res)) {
356 				if (res == -EEXIST) {
357 					res = irq_domain_associate(d->domain,
358 								   irq, irq);
359 					if (unlikely(res)) {
360 						pr_err("domain association "
361 						       "failure\n");
362 						continue;
363 					}
364 				} else {
365 					pr_err("can't identity map IRQ %d\n",
366 					       irq);
367 					continue;
368 				}
369 			}
370 
371 			vect2->enum_id = 0;
372 
373 			/* redirect this interrupts to the first one */
374 			irq_set_chip(irq2, &dummy_irq_chip);
375 			irq_set_chained_handler(irq2, intc_redirect_irq);
376 			irq_set_handler_data(irq2, (void *)irq);
377 		}
378 	}
379 
380 	intc_subgroup_init(desc, d);
381 
382 	/* enable bits matching force_enable after registering irqs */
383 	if (desc->force_enable)
384 		intc_enable_disable_enum(desc, d, desc->force_enable, 1);
385 
386 	d->skip_suspend = desc->skip_syscore_suspend;
387 
388 	nr_intc_controllers++;
389 
390 	return 0;
391 err5:
392 	kfree(d->prio);
393 err4:
394 #ifdef CONFIG_SMP
395 	kfree(d->smp);
396 err3:
397 #endif
398 	kfree(d->reg);
399 err2:
400 	for (k = 0; k < d->nr_windows; k++)
401 		if (d->window[k].virt)
402 			iounmap(d->window[k].virt);
403 
404 	kfree(d->window);
405 err1:
406 	kfree(d);
407 err0:
408 	pr_err("unable to allocate INTC memory\n");
409 
410 	return -ENOMEM;
411 }
412 
413 static int intc_suspend(void)
414 {
415 	struct intc_desc_int *d;
416 
417 	list_for_each_entry(d, &intc_list, list) {
418 		int irq;
419 
420 		if (d->skip_suspend)
421 			continue;
422 
423 		/* enable wakeup irqs belonging to this intc controller */
424 		for_each_active_irq(irq) {
425 			struct irq_data *data;
426 			struct irq_chip *chip;
427 
428 			data = irq_get_irq_data(irq);
429 			chip = irq_data_get_irq_chip(data);
430 			if (chip != &d->chip)
431 				continue;
432 			if (irqd_is_wakeup_set(data))
433 				chip->irq_enable(data);
434 		}
435 	}
436 	return 0;
437 }
438 
439 static void intc_resume(void)
440 {
441 	struct intc_desc_int *d;
442 
443 	list_for_each_entry(d, &intc_list, list) {
444 		int irq;
445 
446 		if (d->skip_suspend)
447 			continue;
448 
449 		for_each_active_irq(irq) {
450 			struct irq_data *data;
451 			struct irq_chip *chip;
452 
453 			data = irq_get_irq_data(irq);
454 			chip = irq_data_get_irq_chip(data);
455 			/*
456 			 * This will catch the redirect and VIRQ cases
457 			 * due to the dummy_irq_chip being inserted.
458 			 */
459 			if (chip != &d->chip)
460 				continue;
461 			if (irqd_irq_disabled(data))
462 				chip->irq_disable(data);
463 			else
464 				chip->irq_enable(data);
465 		}
466 	}
467 }
468 
469 struct syscore_ops intc_syscore_ops = {
470 	.suspend	= intc_suspend,
471 	.resume		= intc_resume,
472 };
473 
474 struct bus_type intc_subsys = {
475 	.name		= "intc",
476 	.dev_name	= "intc",
477 };
478 
479 static ssize_t
480 show_intc_name(struct device *dev, struct device_attribute *attr, char *buf)
481 {
482 	struct intc_desc_int *d;
483 
484 	d = container_of(dev, struct intc_desc_int, dev);
485 
486 	return sprintf(buf, "%s\n", d->chip.name);
487 }
488 
489 static DEVICE_ATTR(name, S_IRUGO, show_intc_name, NULL);
490 
491 static int __init register_intc_devs(void)
492 {
493 	struct intc_desc_int *d;
494 	int error;
495 
496 	register_syscore_ops(&intc_syscore_ops);
497 
498 	error = subsys_system_register(&intc_subsys, NULL);
499 	if (!error) {
500 		list_for_each_entry(d, &intc_list, list) {
501 			d->dev.id = d->index;
502 			d->dev.bus = &intc_subsys;
503 			error = device_register(&d->dev);
504 			if (error == 0)
505 				error = device_create_file(&d->dev,
506 							   &dev_attr_name);
507 			if (error)
508 				break;
509 		}
510 	}
511 
512 	if (error)
513 		pr_err("device registration error\n");
514 
515 	return error;
516 }
517 device_initcall(register_intc_devs);
518