xref: /linux/drivers/sh/intc/core.c (revision cb299ba8b5ef2239429484072fea394cd7581bd7)
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/list.h>
29 #include <linux/spinlock.h>
30 #include <linux/radix-tree.h>
31 #include "internals.h"
32 
33 LIST_HEAD(intc_list);
34 DEFINE_RAW_SPINLOCK(intc_big_lock);
35 unsigned int nr_intc_controllers;
36 
37 /*
38  * Default priority level
39  * - this needs to be at least 2 for 5-bit priorities on 7780
40  */
41 static unsigned int default_prio_level = 2;	/* 2 - 16 */
42 static unsigned int intc_prio_level[NR_IRQS];	/* for now */
43 
44 unsigned int intc_get_dfl_prio_level(void)
45 {
46 	return default_prio_level;
47 }
48 
49 unsigned int intc_get_prio_level(unsigned int irq)
50 {
51 	return intc_prio_level[irq];
52 }
53 
54 void intc_set_prio_level(unsigned int irq, unsigned int level)
55 {
56 	unsigned long flags;
57 
58 	raw_spin_lock_irqsave(&intc_big_lock, flags);
59 	intc_prio_level[irq] = level;
60 	raw_spin_unlock_irqrestore(&intc_big_lock, flags);
61 }
62 
63 static void intc_redirect_irq(unsigned int irq, struct irq_desc *desc)
64 {
65 	generic_handle_irq((unsigned int)get_irq_data(irq));
66 }
67 
68 static void __init intc_register_irq(struct intc_desc *desc,
69 				     struct intc_desc_int *d,
70 				     intc_enum enum_id,
71 				     unsigned int irq)
72 {
73 	struct intc_handle_int *hp;
74 	unsigned int data[2], primary;
75 	unsigned long flags;
76 
77 	/*
78 	 * Register the IRQ position with the global IRQ map, then insert
79 	 * it in to the radix tree.
80 	 */
81 	reserve_irq_vector(irq);
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_warning("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 	disable_irq_nosync(irq);
115 	set_irq_chip_and_handler_name(irq, &d->chip,
116 				      handle_level_irq, "level");
117 	set_irq_chip_data(irq, (void *)data[primary]);
118 
119 	/*
120 	 * set priority level
121 	 */
122 	intc_set_prio_level(irq, intc_get_dfl_prio_level());
123 
124 	/* enable secondary masking method if present */
125 	if (data[!primary])
126 		_intc_enable(irq, data[!primary]);
127 
128 	/* add irq to d->prio list if priority is available */
129 	if (data[1]) {
130 		hp = d->prio + d->nr_prio;
131 		hp->irq = irq;
132 		hp->handle = data[1];
133 
134 		if (primary) {
135 			/*
136 			 * only secondary priority should access registers, so
137 			 * set _INTC_FN(h) = REG_FN_ERR for intc_set_priority()
138 			 */
139 			hp->handle &= ~_INTC_MK(0x0f, 0, 0, 0, 0, 0);
140 			hp->handle |= _INTC_MK(REG_FN_ERR, 0, 0, 0, 0, 0);
141 		}
142 		d->nr_prio++;
143 	}
144 
145 	/* add irq to d->sense list if sense is available */
146 	data[0] = intc_get_sense_handle(desc, d, enum_id);
147 	if (data[0]) {
148 		(d->sense + d->nr_sense)->irq = irq;
149 		(d->sense + d->nr_sense)->handle = data[0];
150 		d->nr_sense++;
151 	}
152 
153 	/* irq should be disabled by default */
154 	d->chip.mask(irq);
155 
156 	intc_set_ack_handle(irq, desc, d, enum_id);
157 	intc_set_dist_handle(irq, desc, d, enum_id);
158 
159 	activate_irq(irq);
160 }
161 
162 static unsigned int __init save_reg(struct intc_desc_int *d,
163 				    unsigned int cnt,
164 				    unsigned long value,
165 				    unsigned int smp)
166 {
167 	if (value) {
168 		value = intc_phys_to_virt(d, value);
169 
170 		d->reg[cnt] = value;
171 #ifdef CONFIG_SMP
172 		d->smp[cnt] = smp;
173 #endif
174 		return 1;
175 	}
176 
177 	return 0;
178 }
179 
180 int __init register_intc_controller(struct intc_desc *desc)
181 {
182 	unsigned int i, k, smp;
183 	struct intc_hw_desc *hw = &desc->hw;
184 	struct intc_desc_int *d;
185 	struct resource *res;
186 
187 	pr_info("Registered controller '%s' with %u IRQs\n",
188 		desc->name, hw->nr_vectors);
189 
190 	d = kzalloc(sizeof(*d), GFP_NOWAIT);
191 	if (!d)
192 		goto err0;
193 
194 	INIT_LIST_HEAD(&d->list);
195 	list_add_tail(&d->list, &intc_list);
196 
197 	raw_spin_lock_init(&d->lock);
198 
199 	d->index = nr_intc_controllers;
200 
201 	if (desc->num_resources) {
202 		d->nr_windows = desc->num_resources;
203 		d->window = kzalloc(d->nr_windows * sizeof(*d->window),
204 				    GFP_NOWAIT);
205 		if (!d->window)
206 			goto err1;
207 
208 		for (k = 0; k < d->nr_windows; k++) {
209 			res = desc->resource + k;
210 			WARN_ON(resource_type(res) != IORESOURCE_MEM);
211 			d->window[k].phys = res->start;
212 			d->window[k].size = resource_size(res);
213 			d->window[k].virt = ioremap_nocache(res->start,
214 							 resource_size(res));
215 			if (!d->window[k].virt)
216 				goto err2;
217 		}
218 	}
219 
220 	d->nr_reg = hw->mask_regs ? hw->nr_mask_regs * 2 : 0;
221 #ifdef CONFIG_INTC_BALANCING
222 	if (d->nr_reg)
223 		d->nr_reg += hw->nr_mask_regs;
224 #endif
225 	d->nr_reg += hw->prio_regs ? hw->nr_prio_regs * 2 : 0;
226 	d->nr_reg += hw->sense_regs ? hw->nr_sense_regs : 0;
227 	d->nr_reg += hw->ack_regs ? hw->nr_ack_regs : 0;
228 	d->nr_reg += hw->subgroups ? hw->nr_subgroups : 0;
229 
230 	d->reg = kzalloc(d->nr_reg * sizeof(*d->reg), GFP_NOWAIT);
231 	if (!d->reg)
232 		goto err2;
233 
234 #ifdef CONFIG_SMP
235 	d->smp = kzalloc(d->nr_reg * sizeof(*d->smp), GFP_NOWAIT);
236 	if (!d->smp)
237 		goto err3;
238 #endif
239 	k = 0;
240 
241 	if (hw->mask_regs) {
242 		for (i = 0; i < hw->nr_mask_regs; i++) {
243 			smp = IS_SMP(hw->mask_regs[i]);
244 			k += save_reg(d, k, hw->mask_regs[i].set_reg, smp);
245 			k += save_reg(d, k, hw->mask_regs[i].clr_reg, smp);
246 #ifdef CONFIG_INTC_BALANCING
247 			k += save_reg(d, k, hw->mask_regs[i].dist_reg, 0);
248 #endif
249 		}
250 	}
251 
252 	if (hw->prio_regs) {
253 		d->prio = kzalloc(hw->nr_vectors * sizeof(*d->prio),
254 				  GFP_NOWAIT);
255 		if (!d->prio)
256 			goto err4;
257 
258 		for (i = 0; i < hw->nr_prio_regs; i++) {
259 			smp = IS_SMP(hw->prio_regs[i]);
260 			k += save_reg(d, k, hw->prio_regs[i].set_reg, smp);
261 			k += save_reg(d, k, hw->prio_regs[i].clr_reg, smp);
262 		}
263 	}
264 
265 	if (hw->sense_regs) {
266 		d->sense = kzalloc(hw->nr_vectors * sizeof(*d->sense),
267 				   GFP_NOWAIT);
268 		if (!d->sense)
269 			goto err5;
270 
271 		for (i = 0; i < hw->nr_sense_regs; i++)
272 			k += save_reg(d, k, hw->sense_regs[i].reg, 0);
273 	}
274 
275 	if (hw->subgroups)
276 		for (i = 0; i < hw->nr_subgroups; i++)
277 			if (hw->subgroups[i].reg)
278 				k+= save_reg(d, k, hw->subgroups[i].reg, 0);
279 
280 	memcpy(&d->chip, &intc_irq_chip, sizeof(struct irq_chip));
281 	d->chip.name = desc->name;
282 
283 	if (hw->ack_regs)
284 		for (i = 0; i < hw->nr_ack_regs; i++)
285 			k += save_reg(d, k, hw->ack_regs[i].set_reg, 0);
286 	else
287 		d->chip.mask_ack = d->chip.disable;
288 
289 	/* disable bits matching force_disable before registering irqs */
290 	if (desc->force_disable)
291 		intc_enable_disable_enum(desc, d, desc->force_disable, 0);
292 
293 	/* disable bits matching force_enable before registering irqs */
294 	if (desc->force_enable)
295 		intc_enable_disable_enum(desc, d, desc->force_enable, 0);
296 
297 	BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
298 
299 	/* register the vectors one by one */
300 	for (i = 0; i < hw->nr_vectors; i++) {
301 		struct intc_vect *vect = hw->vectors + i;
302 		unsigned int irq = evt2irq(vect->vect);
303 		struct irq_desc *irq_desc;
304 
305 		if (!vect->enum_id)
306 			continue;
307 
308 		irq_desc = irq_to_desc_alloc_node(irq, numa_node_id());
309 		if (unlikely(!irq_desc)) {
310 			pr_err("can't get irq_desc for %d\n", irq);
311 			continue;
312 		}
313 
314 		intc_irq_xlate_set(irq, vect->enum_id, d);
315 		intc_register_irq(desc, d, vect->enum_id, irq);
316 
317 		for (k = i + 1; k < hw->nr_vectors; k++) {
318 			struct intc_vect *vect2 = hw->vectors + k;
319 			unsigned int irq2 = evt2irq(vect2->vect);
320 
321 			if (vect->enum_id != vect2->enum_id)
322 				continue;
323 
324 			/*
325 			 * In the case of multi-evt handling and sparse
326 			 * IRQ support, each vector still needs to have
327 			 * its own backing irq_desc.
328 			 */
329 			irq_desc = irq_to_desc_alloc_node(irq2, numa_node_id());
330 			if (unlikely(!irq_desc)) {
331 				pr_err("can't get irq_desc for %d\n", irq2);
332 				continue;
333 			}
334 
335 			vect2->enum_id = 0;
336 
337 			/* redirect this interrupts to the first one */
338 			set_irq_chip(irq2, &dummy_irq_chip);
339 			set_irq_chained_handler(irq2, intc_redirect_irq);
340 			set_irq_data(irq2, (void *)irq);
341 		}
342 	}
343 
344 	intc_subgroup_init(desc, d);
345 
346 	/* enable bits matching force_enable after registering irqs */
347 	if (desc->force_enable)
348 		intc_enable_disable_enum(desc, d, desc->force_enable, 1);
349 
350 	nr_intc_controllers++;
351 
352 	return 0;
353 err5:
354 	kfree(d->prio);
355 err4:
356 #ifdef CONFIG_SMP
357 	kfree(d->smp);
358 err3:
359 #endif
360 	kfree(d->reg);
361 err2:
362 	for (k = 0; k < d->nr_windows; k++)
363 		if (d->window[k].virt)
364 			iounmap(d->window[k].virt);
365 
366 	kfree(d->window);
367 err1:
368 	kfree(d);
369 err0:
370 	pr_err("unable to allocate INTC memory\n");
371 
372 	return -ENOMEM;
373 }
374 
375 static ssize_t
376 show_intc_name(struct sys_device *dev, struct sysdev_attribute *attr, char *buf)
377 {
378 	struct intc_desc_int *d;
379 
380 	d = container_of(dev, struct intc_desc_int, sysdev);
381 
382 	return sprintf(buf, "%s\n", d->chip.name);
383 }
384 
385 static SYSDEV_ATTR(name, S_IRUGO, show_intc_name, NULL);
386 
387 static int intc_suspend(struct sys_device *dev, pm_message_t state)
388 {
389 	struct intc_desc_int *d;
390 	struct irq_desc *desc;
391 	int irq;
392 
393 	/* get intc controller associated with this sysdev */
394 	d = container_of(dev, struct intc_desc_int, sysdev);
395 
396 	switch (state.event) {
397 	case PM_EVENT_ON:
398 		if (d->state.event != PM_EVENT_FREEZE)
399 			break;
400 
401 		for_each_irq_desc(irq, desc) {
402 			/*
403 			 * This will catch the redirect and VIRQ cases
404 			 * due to the dummy_irq_chip being inserted.
405 			 */
406 			if (desc->chip != &d->chip)
407 				continue;
408 			if (desc->status & IRQ_DISABLED)
409 				desc->chip->disable(irq);
410 			else
411 				desc->chip->enable(irq);
412 		}
413 		break;
414 	case PM_EVENT_FREEZE:
415 		/* nothing has to be done */
416 		break;
417 	case PM_EVENT_SUSPEND:
418 		/* enable wakeup irqs belonging to this intc controller */
419 		for_each_irq_desc(irq, desc) {
420 			if (desc->chip != &d->chip)
421 				continue;
422 			if ((desc->status & IRQ_WAKEUP))
423 				desc->chip->enable(irq);
424 		}
425 		break;
426 	}
427 
428 	d->state = state;
429 
430 	return 0;
431 }
432 
433 static int intc_resume(struct sys_device *dev)
434 {
435 	return intc_suspend(dev, PMSG_ON);
436 }
437 
438 struct sysdev_class intc_sysdev_class = {
439 	.name		= "intc",
440 	.suspend	= intc_suspend,
441 	.resume		= intc_resume,
442 };
443 
444 /* register this intc as sysdev to allow suspend/resume */
445 static int __init register_intc_sysdevs(void)
446 {
447 	struct intc_desc_int *d;
448 	int error;
449 
450 	error = sysdev_class_register(&intc_sysdev_class);
451 	if (!error) {
452 		list_for_each_entry(d, &intc_list, list) {
453 			d->sysdev.id = d->index;
454 			d->sysdev.cls = &intc_sysdev_class;
455 			error = sysdev_register(&d->sysdev);
456 			if (error == 0)
457 				error = sysdev_create_file(&d->sysdev,
458 							   &attr_name);
459 			if (error)
460 				break;
461 		}
462 	}
463 
464 	if (error)
465 		pr_err("sysdev registration error\n");
466 
467 	return error;
468 }
469 device_initcall(register_intc_sysdevs);
470