xref: /openbmc/linux/drivers/sh/intc/core.c (revision 63dc02bd)
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/device.h>
29 #include <linux/syscore_ops.h>
30 #include <linux/list.h>
31 #include <linux/spinlock.h>
32 #include <linux/radix-tree.h>
33 #include <linux/export.h>
34 #include <linux/sort.h>
35 #include "internals.h"
36 
37 LIST_HEAD(intc_list);
38 DEFINE_RAW_SPINLOCK(intc_big_lock);
39 static unsigned int nr_intc_controllers;
40 
41 /*
42  * Default priority level
43  * - this needs to be at least 2 for 5-bit priorities on 7780
44  */
45 static unsigned int default_prio_level = 2;	/* 2 - 16 */
46 static unsigned int intc_prio_level[INTC_NR_IRQS];	/* for now */
47 
48 unsigned int intc_get_dfl_prio_level(void)
49 {
50 	return default_prio_level;
51 }
52 
53 unsigned int intc_get_prio_level(unsigned int irq)
54 {
55 	return intc_prio_level[irq];
56 }
57 
58 void intc_set_prio_level(unsigned int irq, unsigned int level)
59 {
60 	unsigned long flags;
61 
62 	raw_spin_lock_irqsave(&intc_big_lock, flags);
63 	intc_prio_level[irq] = level;
64 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
65 }
66 
67 static void intc_redirect_irq(unsigned int irq, struct irq_desc *desc)
68 {
69 	generic_handle_irq((unsigned int)irq_get_handler_data(irq));
70 }
71 
72 static void __init intc_register_irq(struct intc_desc *desc,
73 				     struct intc_desc_int *d,
74 				     intc_enum enum_id,
75 				     unsigned int irq)
76 {
77 	struct intc_handle_int *hp;
78 	struct irq_data *irq_data;
79 	unsigned int data[2], primary;
80 	unsigned long flags;
81 
82 	/*
83 	 * Register the IRQ position with the global IRQ map, then insert
84 	 * it in to the radix tree.
85 	 */
86 	irq_reserve_irq(irq);
87 
88 	raw_spin_lock_irqsave(&intc_big_lock, flags);
89 	radix_tree_insert(&d->tree, enum_id, intc_irq_xlate_get(irq));
90 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
91 
92 	/*
93 	 * Prefer single interrupt source bitmap over other combinations:
94 	 *
95 	 * 1. bitmap, single interrupt source
96 	 * 2. priority, single interrupt source
97 	 * 3. bitmap, multiple interrupt sources (groups)
98 	 * 4. priority, multiple interrupt sources (groups)
99 	 */
100 	data[0] = intc_get_mask_handle(desc, d, enum_id, 0);
101 	data[1] = intc_get_prio_handle(desc, d, enum_id, 0);
102 
103 	primary = 0;
104 	if (!data[0] && data[1])
105 		primary = 1;
106 
107 	if (!data[0] && !data[1])
108 		pr_warning("missing unique irq mask for irq %d (vect 0x%04x)\n",
109 			   irq, irq2evt(irq));
110 
111 	data[0] = data[0] ? data[0] : intc_get_mask_handle(desc, d, enum_id, 1);
112 	data[1] = data[1] ? data[1] : intc_get_prio_handle(desc, d, enum_id, 1);
113 
114 	if (!data[primary])
115 		primary ^= 1;
116 
117 	BUG_ON(!data[primary]); /* must have primary masking method */
118 
119 	irq_data = irq_get_irq_data(irq);
120 
121 	disable_irq_nosync(irq);
122 	irq_set_chip_and_handler_name(irq, &d->chip, handle_level_irq,
123 				      "level");
124 	irq_set_chip_data(irq, (void *)data[primary]);
125 
126 	/*
127 	 * set priority level
128 	 */
129 	intc_set_prio_level(irq, intc_get_dfl_prio_level());
130 
131 	/* enable secondary masking method if present */
132 	if (data[!primary])
133 		_intc_enable(irq_data, data[!primary]);
134 
135 	/* add irq to d->prio list if priority is available */
136 	if (data[1]) {
137 		hp = d->prio + d->nr_prio;
138 		hp->irq = irq;
139 		hp->handle = data[1];
140 
141 		if (primary) {
142 			/*
143 			 * only secondary priority should access registers, so
144 			 * set _INTC_FN(h) = REG_FN_ERR for intc_set_priority()
145 			 */
146 			hp->handle &= ~_INTC_MK(0x0f, 0, 0, 0, 0, 0);
147 			hp->handle |= _INTC_MK(REG_FN_ERR, 0, 0, 0, 0, 0);
148 		}
149 		d->nr_prio++;
150 	}
151 
152 	/* add irq to d->sense list if sense is available */
153 	data[0] = intc_get_sense_handle(desc, d, enum_id);
154 	if (data[0]) {
155 		(d->sense + d->nr_sense)->irq = irq;
156 		(d->sense + d->nr_sense)->handle = data[0];
157 		d->nr_sense++;
158 	}
159 
160 	/* irq should be disabled by default */
161 	d->chip.irq_mask(irq_data);
162 
163 	intc_set_ack_handle(irq, desc, d, enum_id);
164 	intc_set_dist_handle(irq, desc, d, enum_id);
165 
166 	activate_irq(irq);
167 }
168 
169 static unsigned int __init save_reg(struct intc_desc_int *d,
170 				    unsigned int cnt,
171 				    unsigned long value,
172 				    unsigned int smp)
173 {
174 	if (value) {
175 		value = intc_phys_to_virt(d, value);
176 
177 		d->reg[cnt] = value;
178 #ifdef CONFIG_SMP
179 		d->smp[cnt] = smp;
180 #endif
181 		return 1;
182 	}
183 
184 	return 0;
185 }
186 
187 int __init register_intc_controller(struct intc_desc *desc)
188 {
189 	unsigned int i, k, smp;
190 	struct intc_hw_desc *hw = &desc->hw;
191 	struct intc_desc_int *d;
192 	struct resource *res;
193 
194 	pr_info("Registered controller '%s' with %u IRQs\n",
195 		desc->name, hw->nr_vectors);
196 
197 	d = kzalloc(sizeof(*d), GFP_NOWAIT);
198 	if (!d)
199 		goto err0;
200 
201 	INIT_LIST_HEAD(&d->list);
202 	list_add_tail(&d->list, &intc_list);
203 
204 	raw_spin_lock_init(&d->lock);
205 	INIT_RADIX_TREE(&d->tree, GFP_ATOMIC);
206 
207 	d->index = nr_intc_controllers;
208 
209 	if (desc->num_resources) {
210 		d->nr_windows = desc->num_resources;
211 		d->window = kzalloc(d->nr_windows * sizeof(*d->window),
212 				    GFP_NOWAIT);
213 		if (!d->window)
214 			goto err1;
215 
216 		for (k = 0; k < d->nr_windows; k++) {
217 			res = desc->resource + k;
218 			WARN_ON(resource_type(res) != IORESOURCE_MEM);
219 			d->window[k].phys = res->start;
220 			d->window[k].size = resource_size(res);
221 			d->window[k].virt = ioremap_nocache(res->start,
222 							 resource_size(res));
223 			if (!d->window[k].virt)
224 				goto err2;
225 		}
226 	}
227 
228 	d->nr_reg = hw->mask_regs ? hw->nr_mask_regs * 2 : 0;
229 #ifdef CONFIG_INTC_BALANCING
230 	if (d->nr_reg)
231 		d->nr_reg += hw->nr_mask_regs;
232 #endif
233 	d->nr_reg += hw->prio_regs ? hw->nr_prio_regs * 2 : 0;
234 	d->nr_reg += hw->sense_regs ? hw->nr_sense_regs : 0;
235 	d->nr_reg += hw->ack_regs ? hw->nr_ack_regs : 0;
236 	d->nr_reg += hw->subgroups ? hw->nr_subgroups : 0;
237 
238 	d->reg = kzalloc(d->nr_reg * sizeof(*d->reg), GFP_NOWAIT);
239 	if (!d->reg)
240 		goto err2;
241 
242 #ifdef CONFIG_SMP
243 	d->smp = kzalloc(d->nr_reg * sizeof(*d->smp), GFP_NOWAIT);
244 	if (!d->smp)
245 		goto err3;
246 #endif
247 	k = 0;
248 
249 	if (hw->mask_regs) {
250 		for (i = 0; i < hw->nr_mask_regs; i++) {
251 			smp = IS_SMP(hw->mask_regs[i]);
252 			k += save_reg(d, k, hw->mask_regs[i].set_reg, smp);
253 			k += save_reg(d, k, hw->mask_regs[i].clr_reg, smp);
254 #ifdef CONFIG_INTC_BALANCING
255 			k += save_reg(d, k, hw->mask_regs[i].dist_reg, 0);
256 #endif
257 		}
258 	}
259 
260 	if (hw->prio_regs) {
261 		d->prio = kzalloc(hw->nr_vectors * sizeof(*d->prio),
262 				  GFP_NOWAIT);
263 		if (!d->prio)
264 			goto err4;
265 
266 		for (i = 0; i < hw->nr_prio_regs; i++) {
267 			smp = IS_SMP(hw->prio_regs[i]);
268 			k += save_reg(d, k, hw->prio_regs[i].set_reg, smp);
269 			k += save_reg(d, k, hw->prio_regs[i].clr_reg, smp);
270 		}
271 
272 		sort(d->prio, hw->nr_prio_regs, sizeof(*d->prio),
273 		     intc_handle_int_cmp, NULL);
274 	}
275 
276 	if (hw->sense_regs) {
277 		d->sense = kzalloc(hw->nr_vectors * sizeof(*d->sense),
278 				   GFP_NOWAIT);
279 		if (!d->sense)
280 			goto err5;
281 
282 		for (i = 0; i < hw->nr_sense_regs; i++)
283 			k += save_reg(d, k, hw->sense_regs[i].reg, 0);
284 
285 		sort(d->sense, hw->nr_sense_regs, sizeof(*d->sense),
286 		     intc_handle_int_cmp, NULL);
287 	}
288 
289 	if (hw->subgroups)
290 		for (i = 0; i < hw->nr_subgroups; i++)
291 			if (hw->subgroups[i].reg)
292 				k+= save_reg(d, k, hw->subgroups[i].reg, 0);
293 
294 	memcpy(&d->chip, &intc_irq_chip, sizeof(struct irq_chip));
295 	d->chip.name = desc->name;
296 
297 	if (hw->ack_regs)
298 		for (i = 0; i < hw->nr_ack_regs; i++)
299 			k += save_reg(d, k, hw->ack_regs[i].set_reg, 0);
300 	else
301 		d->chip.irq_mask_ack = d->chip.irq_disable;
302 
303 	/* disable bits matching force_disable before registering irqs */
304 	if (desc->force_disable)
305 		intc_enable_disable_enum(desc, d, desc->force_disable, 0);
306 
307 	/* disable bits matching force_enable before registering irqs */
308 	if (desc->force_enable)
309 		intc_enable_disable_enum(desc, d, desc->force_enable, 0);
310 
311 	BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
312 
313 	/* register the vectors one by one */
314 	for (i = 0; i < hw->nr_vectors; i++) {
315 		struct intc_vect *vect = hw->vectors + i;
316 		unsigned int irq = evt2irq(vect->vect);
317 		int res;
318 
319 		if (!vect->enum_id)
320 			continue;
321 
322 		res = irq_alloc_desc_at(irq, numa_node_id());
323 		if (res != irq && res != -EEXIST) {
324 			pr_err("can't get irq_desc for %d\n", irq);
325 			continue;
326 		}
327 
328 		intc_irq_xlate_set(irq, vect->enum_id, d);
329 		intc_register_irq(desc, d, vect->enum_id, irq);
330 
331 		for (k = i + 1; k < hw->nr_vectors; k++) {
332 			struct intc_vect *vect2 = hw->vectors + k;
333 			unsigned int irq2 = evt2irq(vect2->vect);
334 
335 			if (vect->enum_id != vect2->enum_id)
336 				continue;
337 
338 			/*
339 			 * In the case of multi-evt handling and sparse
340 			 * IRQ support, each vector still needs to have
341 			 * its own backing irq_desc.
342 			 */
343 			res = irq_alloc_desc_at(irq2, numa_node_id());
344 			if (res != irq2 && res != -EEXIST) {
345 				pr_err("can't get irq_desc for %d\n", irq2);
346 				continue;
347 			}
348 
349 			vect2->enum_id = 0;
350 
351 			/* redirect this interrupts to the first one */
352 			irq_set_chip(irq2, &dummy_irq_chip);
353 			irq_set_chained_handler(irq2, intc_redirect_irq);
354 			irq_set_handler_data(irq2, (void *)irq);
355 		}
356 	}
357 
358 	intc_subgroup_init(desc, d);
359 
360 	/* enable bits matching force_enable after registering irqs */
361 	if (desc->force_enable)
362 		intc_enable_disable_enum(desc, d, desc->force_enable, 1);
363 
364 	d->skip_suspend = desc->skip_syscore_suspend;
365 
366 	nr_intc_controllers++;
367 
368 	return 0;
369 err5:
370 	kfree(d->prio);
371 err4:
372 #ifdef CONFIG_SMP
373 	kfree(d->smp);
374 err3:
375 #endif
376 	kfree(d->reg);
377 err2:
378 	for (k = 0; k < d->nr_windows; k++)
379 		if (d->window[k].virt)
380 			iounmap(d->window[k].virt);
381 
382 	kfree(d->window);
383 err1:
384 	kfree(d);
385 err0:
386 	pr_err("unable to allocate INTC memory\n");
387 
388 	return -ENOMEM;
389 }
390 
391 static int intc_suspend(void)
392 {
393 	struct intc_desc_int *d;
394 
395 	list_for_each_entry(d, &intc_list, list) {
396 		int irq;
397 
398 		if (d->skip_suspend)
399 			continue;
400 
401 		/* enable wakeup irqs belonging to this intc controller */
402 		for_each_active_irq(irq) {
403 			struct irq_data *data;
404 			struct irq_chip *chip;
405 
406 			data = irq_get_irq_data(irq);
407 			chip = irq_data_get_irq_chip(data);
408 			if (chip != &d->chip)
409 				continue;
410 			if (irqd_is_wakeup_set(data))
411 				chip->irq_enable(data);
412 		}
413 	}
414 	return 0;
415 }
416 
417 static void intc_resume(void)
418 {
419 	struct intc_desc_int *d;
420 
421 	list_for_each_entry(d, &intc_list, list) {
422 		int irq;
423 
424 		if (d->skip_suspend)
425 			continue;
426 
427 		for_each_active_irq(irq) {
428 			struct irq_data *data;
429 			struct irq_chip *chip;
430 
431 			data = irq_get_irq_data(irq);
432 			chip = irq_data_get_irq_chip(data);
433 			/*
434 			 * This will catch the redirect and VIRQ cases
435 			 * due to the dummy_irq_chip being inserted.
436 			 */
437 			if (chip != &d->chip)
438 				continue;
439 			if (irqd_irq_disabled(data))
440 				chip->irq_disable(data);
441 			else
442 				chip->irq_enable(data);
443 		}
444 	}
445 }
446 
447 struct syscore_ops intc_syscore_ops = {
448 	.suspend	= intc_suspend,
449 	.resume		= intc_resume,
450 };
451 
452 struct bus_type intc_subsys = {
453 	.name		= "intc",
454 	.dev_name	= "intc",
455 };
456 
457 static ssize_t
458 show_intc_name(struct device *dev, struct device_attribute *attr, char *buf)
459 {
460 	struct intc_desc_int *d;
461 
462 	d = container_of(dev, struct intc_desc_int, dev);
463 
464 	return sprintf(buf, "%s\n", d->chip.name);
465 }
466 
467 static DEVICE_ATTR(name, S_IRUGO, show_intc_name, NULL);
468 
469 static int __init register_intc_devs(void)
470 {
471 	struct intc_desc_int *d;
472 	int error;
473 
474 	register_syscore_ops(&intc_syscore_ops);
475 
476 	error = subsys_system_register(&intc_subsys, NULL);
477 	if (!error) {
478 		list_for_each_entry(d, &intc_list, list) {
479 			d->dev.id = d->index;
480 			d->dev.bus = &intc_subsys;
481 			error = device_register(&d->dev);
482 			if (error == 0)
483 				error = device_create_file(&d->dev,
484 							   &dev_attr_name);
485 			if (error)
486 				break;
487 		}
488 	}
489 
490 	if (error)
491 		pr_err("device registration error\n");
492 
493 	return error;
494 }
495 device_initcall(register_intc_devs);
496