summaryrefslogtreecommitdiff
path: root/arch/arm/mach-at91/irq.c
blob: febc2ee901a544458a9a47c0e55473263a7c54a6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
/*
 * linux/arch/arm/mach-at91/irq.c
 *
 *  Copyright (C) 2004 SAN People
 *  Copyright (C) 2004 ATMEL
 *  Copyright (C) Rick Bronson
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/bitmap.h>
#include <linux/types.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqdomain.h>
#include <linux/err.h>
#include <linux/slab.h>

#include <mach/hardware.h>
#include <asm/irq.h>
#include <asm/setup.h>

#include <asm/exception.h>
#include <asm/mach/arch.h>
#include <asm/mach/irq.h>
#include <asm/mach/map.h>

#include <mach/at91_aic.h>

void __iomem *at91_aic_base;
static struct irq_domain *at91_aic_domain;
static struct device_node *at91_aic_np;
static unsigned int n_irqs = NR_AIC_IRQS;
static unsigned long at91_aic_caps = 0;

/* AIC5 introduces a Source Select Register */
#define AT91_AIC_CAP_AIC5	(1 << 0)
#define has_aic5()		(at91_aic_caps & AT91_AIC_CAP_AIC5)

#ifdef CONFIG_PM

static unsigned long *wakeups;
static unsigned long *backups;

#define set_backup(bit) set_bit(bit, backups)
#define clear_backup(bit) clear_bit(bit, backups)

static int at91_aic_pm_init(void)
{
	backups = kzalloc(BITS_TO_LONGS(n_irqs) * sizeof(*backups), GFP_KERNEL);
	if (!backups)
		return -ENOMEM;

	wakeups = kzalloc(BITS_TO_LONGS(n_irqs) * sizeof(*backups), GFP_KERNEL);
	if (!wakeups) {
		kfree(backups);
		return -ENOMEM;
	}

	return 0;
}

static int at91_aic_set_wake(struct irq_data *d, unsigned value)
{
	if (unlikely(d->hwirq >= n_irqs))
		return -EINVAL;

	if (value)
		set_bit(d->hwirq, wakeups);
	else
		clear_bit(d->hwirq, wakeups);

	return 0;
}

void at91_irq_suspend(void)
{
	int i = 0, bit;

	if (has_aic5()) {
		/* disable enabled irqs */
		while ((bit = find_next_bit(backups, n_irqs, i)) < n_irqs) {
			at91_aic_write(AT91_AIC5_SSR,
				       bit & AT91_AIC5_INTSEL_MSK);
			at91_aic_write(AT91_AIC5_IDCR, 1);
			i = bit;
		}
		/* enable wakeup irqs */
		i = 0;
		while ((bit = find_next_bit(wakeups, n_irqs, i)) < n_irqs) {
			at91_aic_write(AT91_AIC5_SSR,
				       bit & AT91_AIC5_INTSEL_MSK);
			at91_aic_write(AT91_AIC5_IECR, 1);
			i = bit;
		}
	} else {
		at91_aic_write(AT91_AIC_IDCR, *backups);
		at91_aic_write(AT91_AIC_IECR, *wakeups);
	}
}

void at91_irq_resume(void)
{
	int i = 0, bit;

	if (has_aic5()) {
		/* disable wakeup irqs */
		while ((bit = find_next_bit(wakeups, n_irqs, i)) < n_irqs) {
			at91_aic_write(AT91_AIC5_SSR,
				       bit & AT91_AIC5_INTSEL_MSK);
			at91_aic_write(AT91_AIC5_IDCR, 1);
			i = bit;
		}
		/* enable irqs disabled for suspend */
		i = 0;
		while ((bit = find_next_bit(backups, n_irqs, i)) < n_irqs) {
			at91_aic_write(AT91_AIC5_SSR,
				       bit & AT91_AIC5_INTSEL_MSK);
			at91_aic_write(AT91_AIC5_IECR, 1);
			i = bit;
		}
	} else {
		at91_aic_write(AT91_AIC_IDCR, *wakeups);
		at91_aic_write(AT91_AIC_IECR, *backups);
	}
}

#else
static inline int at91_aic_pm_init(void)
{
	return 0;
}

#define set_backup(bit)
#define clear_backup(bit)
#define at91_aic_set_wake	NULL

#endif /* CONFIG_PM */

asmlinkage void __exception_irq_entry
at91_aic_handle_irq(struct pt_regs *regs)
{
	u32 irqnr;
	u32 irqstat;

	irqnr = at91_aic_read(AT91_AIC_IVR);
	irqstat = at91_aic_read(AT91_AIC_ISR);

	/*
	 * ISR value is 0 when there is no current interrupt or when there is
	 * a spurious interrupt
	 */
	if (!irqstat)
		at91_aic_write(AT91_AIC_EOICR, 0);
	else
		handle_IRQ(irqnr, regs);
}

asmlinkage void __exception_irq_entry
at91_aic5_handle_irq(struct pt_regs *regs)
{
	u32 irqnr;
	u32 irqstat;

	irqnr = at91_aic_read(AT91_AIC5_IVR);
	irqstat = at91_aic_read(AT91_AIC5_ISR);

	if (!irqstat)
		at91_aic_write(AT91_AIC5_EOICR, 0);
	else
		handle_IRQ(irqnr, regs);
}

static void at91_aic_mask_irq(struct irq_data *d)
{
	/* Disable interrupt on AIC */
	at91_aic_write(AT91_AIC_IDCR, 1 << d->hwirq);
	/* Update ISR cache */
	clear_backup(d->hwirq);
}

static void __maybe_unused at91_aic5_mask_irq(struct irq_data *d)
{
	/* Disable interrupt on AIC5 */
	at91_aic_write(AT91_AIC5_SSR, d->hwirq & AT91_AIC5_INTSEL_MSK);
	at91_aic_write(AT91_AIC5_IDCR, 1);
	/* Update ISR cache */
	clear_backup(d->hwirq);
}

static void at91_aic_unmask_irq(struct irq_data *d)
{
	/* Enable interrupt on AIC */
	at91_aic_write(AT91_AIC_IECR, 1 << d->hwirq);
	/* Update ISR cache */
	set_backup(d->hwirq);
}

static void __maybe_unused at91_aic5_unmask_irq(struct irq_data *d)
{
	/* Enable interrupt on AIC5 */
	at91_aic_write(AT91_AIC5_SSR, d->hwirq & AT91_AIC5_INTSEL_MSK);
	at91_aic_write(AT91_AIC5_IECR, 1);
	/* Update ISR cache */
	set_backup(d->hwirq);
}

static void at91_aic_eoi(struct irq_data *d)
{
	/*
	 * Mark end-of-interrupt on AIC, the controller doesn't care about
	 * the value written. Moreover it's a write-only register.
	 */
	at91_aic_write(AT91_AIC_EOICR, 0);
}

static void __maybe_unused at91_aic5_eoi(struct irq_data *d)
{
	at91_aic_write(AT91_AIC5_EOICR, 0);
}

unsigned long *at91_extern_irq;

#define is_extern_irq(hwirq) test_bit(hwirq, at91_extern_irq)

static int at91_aic_compute_srctype(struct irq_data *d, unsigned type)
{
	int srctype;

	switch (type) {
	case IRQ_TYPE_LEVEL_HIGH:
		srctype = AT91_AIC_SRCTYPE_HIGH;
		break;
	case IRQ_TYPE_EDGE_RISING:
		srctype = AT91_AIC_SRCTYPE_RISING;
		break;
	case IRQ_TYPE_LEVEL_LOW:
		if ((d->hwirq == AT91_ID_FIQ) || is_extern_irq(d->hwirq))		/* only supported on external interrupts */
			srctype = AT91_AIC_SRCTYPE_LOW;
		else
			srctype = -EINVAL;
		break;
	case IRQ_TYPE_EDGE_FALLING:
		if ((d->hwirq == AT91_ID_FIQ) || is_extern_irq(d->hwirq))		/* only supported on external interrupts */
			srctype = AT91_AIC_SRCTYPE_FALLING;
		else
			srctype = -EINVAL;
		break;
	default:
		srctype = -EINVAL;
	}

	return srctype;
}

static int at91_aic_set_type(struct irq_data *d, unsigned type)
{
	unsigned int smr;
	int srctype;

	srctype = at91_aic_compute_srctype(d, type);
	if (srctype < 0)
		return srctype;

	if (has_aic5()) {
		at91_aic_write(AT91_AIC5_SSR,
			       d->hwirq & AT91_AIC5_INTSEL_MSK);
		smr = at91_aic_read(AT91_AIC5_SMR) & ~AT91_AIC_SRCTYPE;
		at91_aic_write(AT91_AIC5_SMR, smr | srctype);
	} else {
		smr = at91_aic_read(AT91_AIC_SMR(d->hwirq))
		      & ~AT91_AIC_SRCTYPE;
		at91_aic_write(AT91_AIC_SMR(d->hwirq), smr | srctype);
	}

	return 0;
}

static struct irq_chip at91_aic_chip = {
	.name		= "AIC",
	.irq_mask	= at91_aic_mask_irq,
	.irq_unmask	= at91_aic_unmask_irq,
	.irq_set_type	= at91_aic_set_type,
	.irq_set_wake	= at91_aic_set_wake,
	.irq_eoi	= at91_aic_eoi,
};

static void __init at91_aic_hw_init(unsigned int spu_vector)
{
	int i;

	/*
	 * Perform 8 End Of Interrupt Command to make sure AIC
	 * will not Lock out nIRQ
	 */
	for (i = 0; i < 8; i++)
		at91_aic_write(AT91_AIC_EOICR, 0);

	/*
	 * Spurious Interrupt ID in Spurious Vector Register.
	 * When there is no current interrupt, the IRQ Vector Register
	 * reads the value stored in AIC_SPU
	 */
	at91_aic_write(AT91_AIC_SPU, spu_vector);

	/* No debugging in AIC: Debug (Protect) Control Register */
	at91_aic_write(AT91_AIC_DCR, 0);

	/* Disable and clear all interrupts initially */
	at91_aic_write(AT91_AIC_IDCR, 0xFFFFFFFF);
	at91_aic_write(AT91_AIC_ICCR, 0xFFFFFFFF);
}

static void __init __maybe_unused at91_aic5_hw_init(unsigned int spu_vector)
{
	int i;

	/*
	 * Perform 8 End Of Interrupt Command to make sure AIC
	 * will not Lock out nIRQ
	 */
	for (i = 0; i < 8; i++)
		at91_aic_write(AT91_AIC5_EOICR, 0);

	/*
	 * Spurious Interrupt ID in Spurious Vector Register.
	 * When there is no current interrupt, the IRQ Vector Register
	 * reads the value stored in AIC_SPU
	 */
	at91_aic_write(AT91_AIC5_SPU, spu_vector);

	/* No debugging in AIC: Debug (Protect) Control Register */
	at91_aic_write(AT91_AIC5_DCR, 0);

	/* Disable and clear all interrupts initially */
	for (i = 0; i < n_irqs; i++) {
		at91_aic_write(AT91_AIC5_SSR, i & AT91_AIC5_INTSEL_MSK);
		at91_aic_write(AT91_AIC5_IDCR, 1);
		at91_aic_write(AT91_AIC5_ICCR, 1);
	}
}

#if defined(CONFIG_OF)
static unsigned int *at91_aic_irq_priorities;

static int at91_aic_irq_map(struct irq_domain *h, unsigned int virq,
							irq_hw_number_t hw)
{
	/* Put virq number in Source Vector Register */
	at91_aic_write(AT91_AIC_SVR(hw), virq);

	/* Active Low interrupt, with priority */
	at91_aic_write(AT91_AIC_SMR(hw),
		       AT91_AIC_SRCTYPE_LOW | at91_aic_irq_priorities[hw]);

	irq_set_chip_and_handler(virq, &at91_aic_chip, handle_fasteoi_irq);
	set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);

	return 0;
}

static int at91_aic5_irq_map(struct irq_domain *h, unsigned int virq,
		irq_hw_number_t hw)
{
	at91_aic_write(AT91_AIC5_SSR, hw & AT91_AIC5_INTSEL_MSK);

	/* Put virq number in Source Vector Register */
	at91_aic_write(AT91_AIC5_SVR, virq);

	/* Active Low interrupt, with priority */
	at91_aic_write(AT91_AIC5_SMR,
		       AT91_AIC_SRCTYPE_LOW | at91_aic_irq_priorities[hw]);

	irq_set_chip_and_handler(virq, &at91_aic_chip, handle_fasteoi_irq);
	set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);

	return 0;
}

static int at91_aic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
				const u32 *intspec, unsigned int intsize,
				irq_hw_number_t *out_hwirq, unsigned int *out_type)
{
	if (WARN_ON(intsize < 3))
		return -EINVAL;
	if (WARN_ON(intspec[0] >= n_irqs))
		return -EINVAL;
	if (WARN_ON((intspec[2] < AT91_AIC_IRQ_MIN_PRIORITY)
		    || (intspec[2] > AT91_AIC_IRQ_MAX_PRIORITY)))
		return -EINVAL;

	*out_hwirq = intspec[0];
	*out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
	at91_aic_irq_priorities[*out_hwirq] = intspec[2];

	return 0;
}

static struct irq_domain_ops at91_aic_irq_ops = {
	.map	= at91_aic_irq_map,
	.xlate	= at91_aic_irq_domain_xlate,
};

int __init at91_aic_of_common_init(struct device_node *node,
				    struct device_node *parent)
{
	struct property *prop;
	const __be32 *p;
	u32 val;

	at91_extern_irq = kzalloc(BITS_TO_LONGS(n_irqs)
				  * sizeof(*at91_extern_irq), GFP_KERNEL);
	if (!at91_extern_irq)
		return -ENOMEM;

	if (at91_aic_pm_init()) {
		kfree(at91_extern_irq);
		return -ENOMEM;
	}

	at91_aic_irq_priorities = kzalloc(n_irqs
					  * sizeof(*at91_aic_irq_priorities),
					  GFP_KERNEL);
	if (!at91_aic_irq_priorities)
		return -ENOMEM;

	at91_aic_base = of_iomap(node, 0);
	at91_aic_np = node;

	at91_aic_domain = irq_domain_add_linear(at91_aic_np, n_irqs,
						&at91_aic_irq_ops, NULL);
	if (!at91_aic_domain)
		panic("Unable to add AIC irq domain (DT)\n");

	of_property_for_each_u32(node, "atmel,external-irqs", prop, p, val) {
		if (val >= n_irqs)
			pr_warn("AIC: external irq %d >= %d skip it\n",
				val, n_irqs);
		else
			set_bit(val, at91_extern_irq);
	}

	irq_set_default_host(at91_aic_domain);

	return 0;
}

int __init at91_aic_of_init(struct device_node *node,
				     struct device_node *parent)
{
	int err;

	err = at91_aic_of_common_init(node, parent);
	if (err)
		return err;

	at91_aic_hw_init(n_irqs);

	return 0;
}

int __init at91_aic5_of_init(struct device_node *node,
				     struct device_node *parent)
{
	int err;

	at91_aic_caps |= AT91_AIC_CAP_AIC5;
	n_irqs = NR_AIC5_IRQS;
	at91_aic_chip.irq_ack           = at91_aic5_mask_irq;
	at91_aic_chip.irq_mask		= at91_aic5_mask_irq;
	at91_aic_chip.irq_unmask	= at91_aic5_unmask_irq;
	at91_aic_chip.irq_eoi		= at91_aic5_eoi;
	at91_aic_irq_ops.map		= at91_aic5_irq_map;

	err = at91_aic_of_common_init(node, parent);
	if (err)
		return err;

	at91_aic5_hw_init(n_irqs);

	return 0;
}
#endif

/*
 * Initialize the AIC interrupt controller.
 */
void __init at91_aic_init(unsigned int *priority, unsigned int ext_irq_mask)
{
	unsigned int i;
	int irq_base;

	at91_extern_irq = kzalloc(BITS_TO_LONGS(n_irqs)
				  * sizeof(*at91_extern_irq), GFP_KERNEL);

	if (at91_aic_pm_init() || at91_extern_irq == NULL)
		panic("Unable to allocate bit maps\n");

	*at91_extern_irq = ext_irq_mask;

	at91_aic_base = ioremap(AT91_AIC, 512);
	if (!at91_aic_base)
		panic("Unable to ioremap AIC registers\n");

	/* Add irq domain for AIC */
	irq_base = irq_alloc_descs(-1, 0, n_irqs, 0);
	if (irq_base < 0) {
		WARN(1, "Cannot allocate irq_descs, assuming pre-allocated\n");
		irq_base = 0;
	}
	at91_aic_domain = irq_domain_add_legacy(at91_aic_np, n_irqs,
						irq_base, 0,
						&irq_domain_simple_ops, NULL);

	if (!at91_aic_domain)
		panic("Unable to add AIC irq domain\n");

	irq_set_default_host(at91_aic_domain);

	/*
	 * The IVR is used by macro get_irqnr_and_base to read and verify.
	 * The irq number is NR_AIC_IRQS when a spurious interrupt has occurred.
	 */
	for (i = 0; i < n_irqs; i++) {
		/* Put hardware irq number in Source Vector Register: */
		at91_aic_write(AT91_AIC_SVR(i), NR_IRQS_LEGACY + i);
		/* Active Low interrupt, with the specified priority */
		at91_aic_write(AT91_AIC_SMR(i), AT91_AIC_SRCTYPE_LOW | priority[i]);
		irq_set_chip_and_handler(NR_IRQS_LEGACY + i, &at91_aic_chip, handle_fasteoi_irq);
		set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
	}

	at91_aic_hw_init(n_irqs);
}