xref: /linux/drivers/sh/intc/core.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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, 2010 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/interrupt.h>
26 #include <linux/sh_intc.h>
27 #include <linux/sysdev.h>
28 #include <linux/syscore_ops.h>
29 #include <linux/list.h>
30 #include <linux/spinlock.h>
31 #include <linux/radix-tree.h>
32 #include "internals.h"
33 
34 LIST_HEAD(intc_list);
35 DEFINE_RAW_SPINLOCK(intc_big_lock);
36 unsigned int nr_intc_controllers;
37 
38 /*
39  * Default priority level
40  * - this needs to be at least 2 for 5-bit priorities on 7780
41  */
42 static unsigned int default_prio_level = 2;	/* 2 - 16 */
43 static unsigned int intc_prio_level[NR_IRQS];	/* for now */
44 
45 unsigned int intc_get_dfl_prio_level(void)
46 {
47 	return default_prio_level;
48 }
49 
50 unsigned int intc_get_prio_level(unsigned int irq)
51 {
52 	return intc_prio_level[irq];
53 }
54 
55 void intc_set_prio_level(unsigned int irq, unsigned int level)
56 {
57 	unsigned long flags;
58 
59 	raw_spin_lock_irqsave(&intc_big_lock, flags);
60 	intc_prio_level[irq] = level;
61 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
62 }
63 
64 static void intc_redirect_irq(unsigned int irq, struct irq_desc *desc)
65 {
66 	generic_handle_irq((unsigned int)irq_get_handler_data(irq));
67 }
68 
69 static void __init intc_register_irq(struct intc_desc *desc,
70 				     struct intc_desc_int *d,
71 				     intc_enum enum_id,
72 				     unsigned int irq)
73 {
74 	struct intc_handle_int *hp;
75 	struct irq_data *irq_data;
76 	unsigned int data[2], primary;
77 	unsigned long flags;
78 
79 	/*
80 	 * Register the IRQ position with the global IRQ map, then insert
81 	 * it in to the radix tree.
82 	 */
83 	irq_reserve_irq(irq);
84 
85 	raw_spin_lock_irqsave(&intc_big_lock, flags);
86 	radix_tree_insert(&d->tree, enum_id, intc_irq_xlate_get(irq));
87 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
88 
89 	/*
90 	 * Prefer single interrupt source bitmap over other combinations:
91 	 *
92 	 * 1. bitmap, single interrupt source
93 	 * 2. priority, single interrupt source
94 	 * 3. bitmap, multiple interrupt sources (groups)
95 	 * 4. priority, multiple interrupt sources (groups)
96 	 */
97 	data[0] = intc_get_mask_handle(desc, d, enum_id, 0);
98 	data[1] = intc_get_prio_handle(desc, d, enum_id, 0);
99 
100 	primary = 0;
101 	if (!data[0] && data[1])
102 		primary = 1;
103 
104 	if (!data[0] && !data[1])
105 		pr_warning("missing unique irq mask for irq %d (vect 0x%04x)\n",
106 			   irq, irq2evt(irq));
107 
108 	data[0] = data[0] ? data[0] : intc_get_mask_handle(desc, d, enum_id, 1);
109 	data[1] = data[1] ? data[1] : intc_get_prio_handle(desc, d, enum_id, 1);
110 
111 	if (!data[primary])
112 		primary ^= 1;
113 
114 	BUG_ON(!data[primary]); /* must have primary masking method */
115 
116 	irq_data = irq_get_irq_data(irq);
117 
118 	disable_irq_nosync(irq);
119 	irq_set_chip_and_handler_name(irq, &d->chip, handle_level_irq,
120 				      "level");
121 	irq_set_chip_data(irq, (void *)data[primary]);
122 
123 	/*
124 	 * set priority level
125 	 */
126 	intc_set_prio_level(irq, intc_get_dfl_prio_level());
127 
128 	/* enable secondary masking method if present */
129 	if (data[!primary])
130 		_intc_enable(irq_data, data[!primary]);
131 
132 	/* add irq to d->prio list if priority is available */
133 	if (data[1]) {
134 		hp = d->prio + d->nr_prio;
135 		hp->irq = irq;
136 		hp->handle = data[1];
137 
138 		if (primary) {
139 			/*
140 			 * only secondary priority should access registers, so
141 			 * set _INTC_FN(h) = REG_FN_ERR for intc_set_priority()
142 			 */
143 			hp->handle &= ~_INTC_MK(0x0f, 0, 0, 0, 0, 0);
144 			hp->handle |= _INTC_MK(REG_FN_ERR, 0, 0, 0, 0, 0);
145 		}
146 		d->nr_prio++;
147 	}
148 
149 	/* add irq to d->sense list if sense is available */
150 	data[0] = intc_get_sense_handle(desc, d, enum_id);
151 	if (data[0]) {
152 		(d->sense + d->nr_sense)->irq = irq;
153 		(d->sense + d->nr_sense)->handle = data[0];
154 		d->nr_sense++;
155 	}
156 
157 	/* irq should be disabled by default */
158 	d->chip.irq_mask(irq_data);
159 
160 	intc_set_ack_handle(irq, desc, d, enum_id);
161 	intc_set_dist_handle(irq, desc, d, enum_id);
162 
163 	activate_irq(irq);
164 }
165 
166 static unsigned int __init save_reg(struct intc_desc_int *d,
167 				    unsigned int cnt,
168 				    unsigned long value,
169 				    unsigned int smp)
170 {
171 	if (value) {
172 		value = intc_phys_to_virt(d, value);
173 
174 		d->reg[cnt] = value;
175 #ifdef CONFIG_SMP
176 		d->smp[cnt] = smp;
177 #endif
178 		return 1;
179 	}
180 
181 	return 0;
182 }
183 
184 int __init register_intc_controller(struct intc_desc *desc)
185 {
186 	unsigned int i, k, smp;
187 	struct intc_hw_desc *hw = &desc->hw;
188 	struct intc_desc_int *d;
189 	struct resource *res;
190 
191 	pr_info("Registered controller '%s' with %u IRQs\n",
192 		desc->name, hw->nr_vectors);
193 
194 	d = kzalloc(sizeof(*d), GFP_NOWAIT);
195 	if (!d)
196 		goto err0;
197 
198 	INIT_LIST_HEAD(&d->list);
199 	list_add_tail(&d->list, &intc_list);
200 
201 	raw_spin_lock_init(&d->lock);
202 	INIT_RADIX_TREE(&d->tree, GFP_ATOMIC);
203 
204 	d->index = nr_intc_controllers;
205 
206 	if (desc->num_resources) {
207 		d->nr_windows = desc->num_resources;
208 		d->window = kzalloc(d->nr_windows * sizeof(*d->window),
209 				    GFP_NOWAIT);
210 		if (!d->window)
211 			goto err1;
212 
213 		for (k = 0; k < d->nr_windows; k++) {
214 			res = desc->resource + k;
215 			WARN_ON(resource_type(res) != IORESOURCE_MEM);
216 			d->window[k].phys = res->start;
217 			d->window[k].size = resource_size(res);
218 			d->window[k].virt = ioremap_nocache(res->start,
219 							 resource_size(res));
220 			if (!d->window[k].virt)
221 				goto err2;
222 		}
223 	}
224 
225 	d->nr_reg = hw->mask_regs ? hw->nr_mask_regs * 2 : 0;
226 #ifdef CONFIG_INTC_BALANCING
227 	if (d->nr_reg)
228 		d->nr_reg += hw->nr_mask_regs;
229 #endif
230 	d->nr_reg += hw->prio_regs ? hw->nr_prio_regs * 2 : 0;
231 	d->nr_reg += hw->sense_regs ? hw->nr_sense_regs : 0;
232 	d->nr_reg += hw->ack_regs ? hw->nr_ack_regs : 0;
233 	d->nr_reg += hw->subgroups ? hw->nr_subgroups : 0;
234 
235 	d->reg = kzalloc(d->nr_reg * sizeof(*d->reg), GFP_NOWAIT);
236 	if (!d->reg)
237 		goto err2;
238 
239 #ifdef CONFIG_SMP
240 	d->smp = kzalloc(d->nr_reg * sizeof(*d->smp), GFP_NOWAIT);
241 	if (!d->smp)
242 		goto err3;
243 #endif
244 	k = 0;
245 
246 	if (hw->mask_regs) {
247 		for (i = 0; i < hw->nr_mask_regs; i++) {
248 			smp = IS_SMP(hw->mask_regs[i]);
249 			k += save_reg(d, k, hw->mask_regs[i].set_reg, smp);
250 			k += save_reg(d, k, hw->mask_regs[i].clr_reg, smp);
251 #ifdef CONFIG_INTC_BALANCING
252 			k += save_reg(d, k, hw->mask_regs[i].dist_reg, 0);
253 #endif
254 		}
255 	}
256 
257 	if (hw->prio_regs) {
258 		d->prio = kzalloc(hw->nr_vectors * sizeof(*d->prio),
259 				  GFP_NOWAIT);
260 		if (!d->prio)
261 			goto err4;
262 
263 		for (i = 0; i < hw->nr_prio_regs; i++) {
264 			smp = IS_SMP(hw->prio_regs[i]);
265 			k += save_reg(d, k, hw->prio_regs[i].set_reg, smp);
266 			k += save_reg(d, k, hw->prio_regs[i].clr_reg, smp);
267 		}
268 	}
269 
270 	if (hw->sense_regs) {
271 		d->sense = kzalloc(hw->nr_vectors * sizeof(*d->sense),
272 				   GFP_NOWAIT);
273 		if (!d->sense)
274 			goto err5;
275 
276 		for (i = 0; i < hw->nr_sense_regs; i++)
277 			k += save_reg(d, k, hw->sense_regs[i].reg, 0);
278 	}
279 
280 	if (hw->subgroups)
281 		for (i = 0; i < hw->nr_subgroups; i++)
282 			if (hw->subgroups[i].reg)
283 				k+= save_reg(d, k, hw->subgroups[i].reg, 0);
284 
285 	memcpy(&d->chip, &intc_irq_chip, sizeof(struct irq_chip));
286 	d->chip.name = desc->name;
287 
288 	if (hw->ack_regs)
289 		for (i = 0; i < hw->nr_ack_regs; i++)
290 			k += save_reg(d, k, hw->ack_regs[i].set_reg, 0);
291 	else
292 		d->chip.irq_mask_ack = d->chip.irq_disable;
293 
294 	/* disable bits matching force_disable before registering irqs */
295 	if (desc->force_disable)
296 		intc_enable_disable_enum(desc, d, desc->force_disable, 0);
297 
298 	/* disable bits matching force_enable before registering irqs */
299 	if (desc->force_enable)
300 		intc_enable_disable_enum(desc, d, desc->force_enable, 0);
301 
302 	BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
303 
304 	/* register the vectors one by one */
305 	for (i = 0; i < hw->nr_vectors; i++) {
306 		struct intc_vect *vect = hw->vectors + i;
307 		unsigned int irq = evt2irq(vect->vect);
308 		int res;
309 
310 		if (!vect->enum_id)
311 			continue;
312 
313 		res = irq_alloc_desc_at(irq, numa_node_id());
314 		if (res != irq && res != -EEXIST) {
315 			pr_err("can't get irq_desc for %d\n", irq);
316 			continue;
317 		}
318 
319 		intc_irq_xlate_set(irq, vect->enum_id, d);
320 		intc_register_irq(desc, d, vect->enum_id, irq);
321 
322 		for (k = i + 1; k < hw->nr_vectors; k++) {
323 			struct intc_vect *vect2 = hw->vectors + k;
324 			unsigned int irq2 = evt2irq(vect2->vect);
325 
326 			if (vect->enum_id != vect2->enum_id)
327 				continue;
328 
329 			/*
330 			 * In the case of multi-evt handling and sparse
331 			 * IRQ support, each vector still needs to have
332 			 * its own backing irq_desc.
333 			 */
334 			res = irq_alloc_desc_at(irq2, numa_node_id());
335 			if (res != irq2 && res != -EEXIST) {
336 				pr_err("can't get irq_desc for %d\n", irq2);
337 				continue;
338 			}
339 
340 			vect2->enum_id = 0;
341 
342 			/* redirect this interrupts to the first one */
343 			irq_set_chip(irq2, &dummy_irq_chip);
344 			irq_set_chained_handler(irq2, intc_redirect_irq);
345 			irq_set_handler_data(irq2, (void *)irq);
346 		}
347 	}
348 
349 	intc_subgroup_init(desc, d);
350 
351 	/* enable bits matching force_enable after registering irqs */
352 	if (desc->force_enable)
353 		intc_enable_disable_enum(desc, d, desc->force_enable, 1);
354 
355 	nr_intc_controllers++;
356 
357 	return 0;
358 err5:
359 	kfree(d->prio);
360 err4:
361 #ifdef CONFIG_SMP
362 	kfree(d->smp);
363 err3:
364 #endif
365 	kfree(d->reg);
366 err2:
367 	for (k = 0; k < d->nr_windows; k++)
368 		if (d->window[k].virt)
369 			iounmap(d->window[k].virt);
370 
371 	kfree(d->window);
372 err1:
373 	kfree(d);
374 err0:
375 	pr_err("unable to allocate INTC memory\n");
376 
377 	return -ENOMEM;
378 }
379 
380 static int intc_suspend(void)
381 {
382 	struct intc_desc_int *d;
383 
384 	list_for_each_entry(d, &intc_list, list) {
385 		int irq;
386 
387 		/* enable wakeup irqs belonging to this intc controller */
388 		for_each_active_irq(irq) {
389 			struct irq_data *data;
390 			struct irq_chip *chip;
391 
392 			data = irq_get_irq_data(irq);
393 			chip = irq_data_get_irq_chip(data);
394 			if (chip != &d->chip)
395 				continue;
396 			if (irqd_is_wakeup_set(data))
397 				chip->irq_enable(data);
398 		}
399 	}
400 	return 0;
401 }
402 
403 static void intc_resume(void)
404 {
405 	struct intc_desc_int *d;
406 
407 	list_for_each_entry(d, &intc_list, list) {
408 		int irq;
409 
410 		for_each_active_irq(irq) {
411 			struct irq_data *data;
412 			struct irq_chip *chip;
413 
414 			data = irq_get_irq_data(irq);
415 			chip = irq_data_get_irq_chip(data);
416 			/*
417 			 * This will catch the redirect and VIRQ cases
418 			 * due to the dummy_irq_chip being inserted.
419 			 */
420 			if (chip != &d->chip)
421 				continue;
422 			if (irqd_irq_disabled(data))
423 				chip->irq_disable(data);
424 			else
425 				chip->irq_enable(data);
426 		}
427 	}
428 }
429 
430 struct syscore_ops intc_syscore_ops = {
431 	.suspend	= intc_suspend,
432 	.resume		= intc_resume,
433 };
434 
435 struct sysdev_class intc_sysdev_class = {
436 	.name		= "intc",
437 };
438 
439 static ssize_t
440 show_intc_name(struct sys_device *dev, struct sysdev_attribute *attr, char *buf)
441 {
442 	struct intc_desc_int *d;
443 
444 	d = container_of(dev, struct intc_desc_int, sysdev);
445 
446 	return sprintf(buf, "%s\n", d->chip.name);
447 }
448 
449 static SYSDEV_ATTR(name, S_IRUGO, show_intc_name, NULL);
450 
451 static int __init register_intc_sysdevs(void)
452 {
453 	struct intc_desc_int *d;
454 	int error;
455 
456 	register_syscore_ops(&intc_syscore_ops);
457 
458 	error = sysdev_class_register(&intc_sysdev_class);
459 	if (!error) {
460 		list_for_each_entry(d, &intc_list, list) {
461 			d->sysdev.id = d->index;
462 			d->sysdev.cls = &intc_sysdev_class;
463 			error = sysdev_register(&d->sysdev);
464 			if (error == 0)
465 				error = sysdev_create_file(&d->sysdev,
466 							   &attr_name);
467 			if (error)
468 				break;
469 		}
470 	}
471 
472 	if (error)
473 		pr_err("sysdev registration error\n");
474 
475 	return error;
476 }
477 device_initcall(register_intc_sysdevs);
478