summaryrefslogtreecommitdiff
path: root/drivers/irqchip/irq-mvebu-sei.c
blob: 3a7b7a7f20ca7a4223888bab5ae6392f9b3b45d4 (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
// SPDX-License-Identifier: GPL-2.0

#define pr_fmt(fmt) "mvebu-sei: " fmt

#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/msi.h>
#include <linux/platform_device.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>

/* Cause register */
#define GICP_SECR(idx)		(0x0  + ((idx) * 0x4))
/* Mask register */
#define GICP_SEMR(idx)		(0x20 + ((idx) * 0x4))
#define GICP_SET_SEI_OFFSET	0x30

#define SEI_IRQ_COUNT_PER_REG	32
#define SEI_IRQ_REG_COUNT	2
#define SEI_IRQ_COUNT		(SEI_IRQ_COUNT_PER_REG * SEI_IRQ_REG_COUNT)
#define SEI_IRQ_REG_IDX(irq_id)	((irq_id) / SEI_IRQ_COUNT_PER_REG)
#define SEI_IRQ_REG_BIT(irq_id)	((irq_id) % SEI_IRQ_COUNT_PER_REG)

struct mvebu_sei_interrupt_range {
	u32 first;
	u32 size;
};

struct mvebu_sei_caps {
	struct mvebu_sei_interrupt_range ap_range;
	struct mvebu_sei_interrupt_range cp_range;
};

struct mvebu_sei {
	struct device *dev;
	void __iomem *base;
	struct resource *res;
	struct irq_domain *sei_domain;
	struct irq_domain *ap_domain;
	struct irq_domain *cp_domain;
	const struct mvebu_sei_caps *caps;

	/* Lock on MSI allocations/releases */
	struct mutex cp_msi_lock;
	DECLARE_BITMAP(cp_msi_bitmap, SEI_IRQ_COUNT);

	/* Lock on IRQ masking register */
	raw_spinlock_t mask_lock;
};

static void mvebu_sei_ack_irq(struct irq_data *d)
{
	struct mvebu_sei *sei = irq_data_get_irq_chip_data(d);
	u32 reg_idx = SEI_IRQ_REG_IDX(d->hwirq);

	writel_relaxed(BIT(SEI_IRQ_REG_BIT(d->hwirq)),
		       sei->base + GICP_SECR(reg_idx));
}

static void mvebu_sei_mask_irq(struct irq_data *d)
{
	struct mvebu_sei *sei = irq_data_get_irq_chip_data(d);
	u32 reg, reg_idx = SEI_IRQ_REG_IDX(d->hwirq);
	unsigned long flags;

	/* 1 disables the interrupt */
	raw_spin_lock_irqsave(&sei->mask_lock, flags);
	reg = readl_relaxed(sei->base + GICP_SEMR(reg_idx));
	reg |= BIT(SEI_IRQ_REG_BIT(d->hwirq));
	writel_relaxed(reg, sei->base + GICP_SEMR(reg_idx));
	raw_spin_unlock_irqrestore(&sei->mask_lock, flags);
}

static void mvebu_sei_unmask_irq(struct irq_data *d)
{
	struct mvebu_sei *sei = irq_data_get_irq_chip_data(d);
	u32 reg, reg_idx = SEI_IRQ_REG_IDX(d->hwirq);
	unsigned long flags;

	/* 0 enables the interrupt */
	raw_spin_lock_irqsave(&sei->mask_lock, flags);
	reg = readl_relaxed(sei->base + GICP_SEMR(reg_idx));
	reg &= ~BIT(SEI_IRQ_REG_BIT(d->hwirq));
	writel_relaxed(reg, sei->base + GICP_SEMR(reg_idx));
	raw_spin_unlock_irqrestore(&sei->mask_lock, flags);
}

static int mvebu_sei_set_affinity(struct irq_data *d,
				  const struct cpumask *mask_val,
				  bool force)
{
	return -EINVAL;
}

static int mvebu_sei_set_irqchip_state(struct irq_data *d,
				       enum irqchip_irq_state which,
				       bool state)
{
	/* We can only clear the pending state by acking the interrupt */
	if (which != IRQCHIP_STATE_PENDING || state)
		return -EINVAL;

	mvebu_sei_ack_irq(d);
	return 0;
}

static struct irq_chip mvebu_sei_irq_chip = {
	.name			= "SEI",
	.irq_ack		= mvebu_sei_ack_irq,
	.irq_mask		= mvebu_sei_mask_irq,
	.irq_unmask		= mvebu_sei_unmask_irq,
	.irq_set_affinity       = mvebu_sei_set_affinity,
	.irq_set_irqchip_state	= mvebu_sei_set_irqchip_state,
};

static int mvebu_sei_ap_set_type(struct irq_data *data, unsigned int type)
{
	if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_LEVEL_HIGH)
		return -EINVAL;

	return 0;
}

static struct irq_chip mvebu_sei_ap_irq_chip = {
	.name			= "AP SEI",
	.irq_ack		= irq_chip_ack_parent,
	.irq_mask		= irq_chip_mask_parent,
	.irq_unmask		= irq_chip_unmask_parent,
	.irq_set_affinity       = irq_chip_set_affinity_parent,
	.irq_set_type		= mvebu_sei_ap_set_type,
};

static void mvebu_sei_cp_compose_msi_msg(struct irq_data *data,
					 struct msi_msg *msg)
{
	struct mvebu_sei *sei = data->chip_data;
	phys_addr_t set = sei->res->start + GICP_SET_SEI_OFFSET;

	msg->data = data->hwirq + sei->caps->cp_range.first;
	msg->address_lo = lower_32_bits(set);
	msg->address_hi = upper_32_bits(set);
}

static int mvebu_sei_cp_set_type(struct irq_data *data, unsigned int type)
{
	if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_EDGE_RISING)
		return -EINVAL;

	return 0;
}

static struct irq_chip mvebu_sei_cp_irq_chip = {
	.name			= "CP SEI",
	.irq_ack		= irq_chip_ack_parent,
	.irq_mask		= irq_chip_mask_parent,
	.irq_unmask		= irq_chip_unmask_parent,
	.irq_set_affinity       = irq_chip_set_affinity_parent,
	.irq_set_type		= mvebu_sei_cp_set_type,
	.irq_compose_msi_msg	= mvebu_sei_cp_compose_msi_msg,
};

static int mvebu_sei_domain_alloc(struct irq_domain *domain, unsigned int virq,
				  unsigned int nr_irqs, void *arg)
{
	struct mvebu_sei *sei = domain->host_data;
	struct irq_fwspec *fwspec = arg;

	/* Not much to do, just setup the irqdata */
	irq_domain_set_hwirq_and_chip(domain, virq, fwspec->param[0],
				      &mvebu_sei_irq_chip, sei);

	return 0;
}

static void mvebu_sei_domain_free(struct irq_domain *domain, unsigned int virq,
				  unsigned int nr_irqs)
{
	int i;

	for (i = 0; i < nr_irqs; i++) {
		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
		irq_set_handler(virq + i, NULL);
		irq_domain_reset_irq_data(d);
	}
}

static const struct irq_domain_ops mvebu_sei_domain_ops = {
	.alloc	= mvebu_sei_domain_alloc,
	.free	= mvebu_sei_domain_free,
};

static int mvebu_sei_ap_translate(struct irq_domain *domain,
				  struct irq_fwspec *fwspec,
				  unsigned long *hwirq,
				  unsigned int *type)
{
	*hwirq = fwspec->param[0];
	*type  = IRQ_TYPE_LEVEL_HIGH;

	return 0;
}

static int mvebu_sei_ap_alloc(struct irq_domain *domain, unsigned int virq,
			      unsigned int nr_irqs, void *arg)
{
	struct mvebu_sei *sei = domain->host_data;
	struct irq_fwspec fwspec;
	unsigned long hwirq;
	unsigned int type;
	int err;

	mvebu_sei_ap_translate(domain, arg, &hwirq, &type);

	fwspec.fwnode = domain->parent->fwnode;
	fwspec.param_count = 1;
	fwspec.param[0] = hwirq + sei->caps->ap_range.first;

	err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
	if (err)
		return err;

	irq_domain_set_info(domain, virq, hwirq,
			    &mvebu_sei_ap_irq_chip, sei,
			    handle_level_irq, NULL, NULL);
	irq_set_probe(virq);

	return 0;
}

static const struct irq_domain_ops mvebu_sei_ap_domain_ops = {
	.translate	= mvebu_sei_ap_translate,
	.alloc		= mvebu_sei_ap_alloc,
	.free		= irq_domain_free_irqs_parent,
};

static void mvebu_sei_cp_release_irq(struct mvebu_sei *sei, unsigned long hwirq)
{
	mutex_lock(&sei->cp_msi_lock);
	clear_bit(hwirq, sei->cp_msi_bitmap);
	mutex_unlock(&sei->cp_msi_lock);
}

static int mvebu_sei_cp_domain_alloc(struct irq_domain *domain,
				     unsigned int virq, unsigned int nr_irqs,
				     void *args)
{
	struct mvebu_sei *sei = domain->host_data;
	struct irq_fwspec fwspec;
	unsigned long hwirq;
	int ret;

	/* The software only supports single allocations for now */
	if (nr_irqs != 1)
		return -ENOTSUPP;

	mutex_lock(&sei->cp_msi_lock);
	hwirq = find_first_zero_bit(sei->cp_msi_bitmap,
				    sei->caps->cp_range.size);
	if (hwirq < sei->caps->cp_range.size)
		set_bit(hwirq, sei->cp_msi_bitmap);
	mutex_unlock(&sei->cp_msi_lock);

	if (hwirq == sei->caps->cp_range.size)
		return -ENOSPC;

	fwspec.fwnode = domain->parent->fwnode;
	fwspec.param_count = 1;
	fwspec.param[0] = hwirq + sei->caps->cp_range.first;

	ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
	if (ret)
		goto free_irq;

	irq_domain_set_info(domain, virq, hwirq,
			    &mvebu_sei_cp_irq_chip, sei,
			    handle_edge_irq, NULL, NULL);

	return 0;

free_irq:
	mvebu_sei_cp_release_irq(sei, hwirq);
	return ret;
}

static void mvebu_sei_cp_domain_free(struct irq_domain *domain,
				     unsigned int virq, unsigned int nr_irqs)
{
	struct mvebu_sei *sei = domain->host_data;
	struct irq_data *d = irq_domain_get_irq_data(domain, virq);

	if (nr_irqs != 1 || d->hwirq >= sei->caps->cp_range.size) {
		dev_err(sei->dev, "Invalid hwirq %lu\n", d->hwirq);
		return;
	}

	mvebu_sei_cp_release_irq(sei, d->hwirq);
	irq_domain_free_irqs_parent(domain, virq, 1);
}

static const struct irq_domain_ops mvebu_sei_cp_domain_ops = {
	.alloc	= mvebu_sei_cp_domain_alloc,
	.free	= mvebu_sei_cp_domain_free,
};

static struct irq_chip mvebu_sei_msi_irq_chip = {
	.name		= "SEI pMSI",
	.irq_ack	= irq_chip_ack_parent,
	.irq_set_type	= irq_chip_set_type_parent,
};

static struct msi_domain_ops mvebu_sei_msi_ops = {
};

static struct msi_domain_info mvebu_sei_msi_domain_info = {
	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS,
	.ops	= &mvebu_sei_msi_ops,
	.chip	= &mvebu_sei_msi_irq_chip,
};

static void mvebu_sei_handle_cascade_irq(struct irq_desc *desc)
{
	struct mvebu_sei *sei = irq_desc_get_handler_data(desc);
	struct irq_chip *chip = irq_desc_get_chip(desc);
	u32 idx;

	chained_irq_enter(chip, desc);

	for (idx = 0; idx < SEI_IRQ_REG_COUNT; idx++) {
		unsigned long irqmap;
		int bit;

		irqmap = readl_relaxed(sei->base + GICP_SECR(idx));
		for_each_set_bit(bit, &irqmap, SEI_IRQ_COUNT_PER_REG) {
			unsigned long hwirq;
			unsigned int virq;

			hwirq = idx * SEI_IRQ_COUNT_PER_REG + bit;
			virq = irq_find_mapping(sei->sei_domain, hwirq);
			if (likely(virq)) {
				generic_handle_irq(virq);
				continue;
			}

			dev_warn(sei->dev,
				 "Spurious IRQ detected (hwirq %lu)\n", hwirq);
		}
	}

	chained_irq_exit(chip, desc);
}

static void mvebu_sei_reset(struct mvebu_sei *sei)
{
	u32 reg_idx;

	/* Clear IRQ cause registers, mask all interrupts */
	for (reg_idx = 0; reg_idx < SEI_IRQ_REG_COUNT; reg_idx++) {
		writel_relaxed(0xFFFFFFFF, sei->base + GICP_SECR(reg_idx));
		writel_relaxed(0xFFFFFFFF, sei->base + GICP_SEMR(reg_idx));
	}
}

static int mvebu_sei_probe(struct platform_device *pdev)
{
	struct device_node *node = pdev->dev.of_node;
	struct irq_domain *plat_domain;
	struct mvebu_sei *sei;
	u32 parent_irq;
	int ret;

	sei = devm_kzalloc(&pdev->dev, sizeof(*sei), GFP_KERNEL);
	if (!sei)
		return -ENOMEM;

	sei->dev = &pdev->dev;

	mutex_init(&sei->cp_msi_lock);
	raw_spin_lock_init(&sei->mask_lock);

	sei->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	sei->base = devm_ioremap_resource(sei->dev, sei->res);
	if (IS_ERR(sei->base))
		return PTR_ERR(sei->base);

	/* Retrieve the SEI capabilities with the interrupt ranges */
	sei->caps = of_device_get_match_data(&pdev->dev);
	if (!sei->caps) {
		dev_err(sei->dev,
			"Could not retrieve controller capabilities\n");
		return -EINVAL;
	}

	/*
	 * Reserve the single (top-level) parent SPI IRQ from which all the
	 * interrupts handled by this driver will be signaled.
	 */
	parent_irq = irq_of_parse_and_map(node, 0);
	if (parent_irq <= 0) {
		dev_err(sei->dev, "Failed to retrieve top-level SPI IRQ\n");
		return -ENODEV;
	}

	/* Create the root SEI domain */
	sei->sei_domain = irq_domain_create_linear(of_node_to_fwnode(node),
						   (sei->caps->ap_range.size +
						    sei->caps->cp_range.size),
						   &mvebu_sei_domain_ops,
						   sei);
	if (!sei->sei_domain) {
		dev_err(sei->dev, "Failed to create SEI IRQ domain\n");
		ret = -ENOMEM;
		goto dispose_irq;
	}

	irq_domain_update_bus_token(sei->sei_domain, DOMAIN_BUS_NEXUS);

	/* Create the 'wired' domain */
	sei->ap_domain = irq_domain_create_hierarchy(sei->sei_domain, 0,
						     sei->caps->ap_range.size,
						     of_node_to_fwnode(node),
						     &mvebu_sei_ap_domain_ops,
						     sei);
	if (!sei->ap_domain) {
		dev_err(sei->dev, "Failed to create AP IRQ domain\n");
		ret = -ENOMEM;
		goto remove_sei_domain;
	}

	irq_domain_update_bus_token(sei->ap_domain, DOMAIN_BUS_WIRED);

	/* Create the 'MSI' domain */
	sei->cp_domain = irq_domain_create_hierarchy(sei->sei_domain, 0,
						     sei->caps->cp_range.size,
						     of_node_to_fwnode(node),
						     &mvebu_sei_cp_domain_ops,
						     sei);
	if (!sei->cp_domain) {
		pr_err("Failed to create CPs IRQ domain\n");
		ret = -ENOMEM;
		goto remove_ap_domain;
	}

	irq_domain_update_bus_token(sei->cp_domain, DOMAIN_BUS_GENERIC_MSI);

	plat_domain = platform_msi_create_irq_domain(of_node_to_fwnode(node),
						     &mvebu_sei_msi_domain_info,
						     sei->cp_domain);
	if (!plat_domain) {
		pr_err("Failed to create CPs MSI domain\n");
		ret = -ENOMEM;
		goto remove_cp_domain;
	}

	mvebu_sei_reset(sei);

	irq_set_chained_handler_and_data(parent_irq,
					 mvebu_sei_handle_cascade_irq,
					 sei);

	return 0;

remove_cp_domain:
	irq_domain_remove(sei->cp_domain);
remove_ap_domain:
	irq_domain_remove(sei->ap_domain);
remove_sei_domain:
	irq_domain_remove(sei->sei_domain);
dispose_irq:
	irq_dispose_mapping(parent_irq);

	return ret;
}

static struct mvebu_sei_caps mvebu_sei_ap806_caps = {
	.ap_range = {
		.first = 0,
		.size = 21,
	},
	.cp_range = {
		.first = 21,
		.size = 43,
	},
};

static const struct of_device_id mvebu_sei_of_match[] = {
	{
		.compatible = "marvell,ap806-sei",
		.data = &mvebu_sei_ap806_caps,
	},
	{},
};

static struct platform_driver mvebu_sei_driver = {
	.probe  = mvebu_sei_probe,
	.driver = {
		.name = "mvebu-sei",
		.of_match_table = mvebu_sei_of_match,
	},
};
builtin_platform_driver(mvebu_sei_driver);