summaryrefslogtreecommitdiff
path: root/drivers/mailbox/tegra-hsp.c
blob: 0cde356c11abcb5cc0d1596e9ef0888acf883662 (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
/*
 * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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.
 */

#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/mailbox_controller.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#include <dt-bindings/mailbox/tegra186-hsp.h>

#define HSP_INT_DIMENSIONING	0x380
#define HSP_nSM_SHIFT		0
#define HSP_nSS_SHIFT		4
#define HSP_nAS_SHIFT		8
#define HSP_nDB_SHIFT		12
#define HSP_nSI_SHIFT		16
#define HSP_nINT_MASK		0xf

#define HSP_DB_TRIGGER	0x0
#define HSP_DB_ENABLE	0x4
#define HSP_DB_RAW	0x8
#define HSP_DB_PENDING	0xc

#define HSP_DB_CCPLEX		1
#define HSP_DB_BPMP		3
#define HSP_DB_MAX		7

struct tegra_hsp_channel;
struct tegra_hsp;

struct tegra_hsp_channel {
	struct tegra_hsp *hsp;
	struct mbox_chan *chan;
	void __iomem *regs;
};

struct tegra_hsp_doorbell {
	struct tegra_hsp_channel channel;
	struct list_head list;
	const char *name;
	unsigned int master;
	unsigned int index;
};

struct tegra_hsp_db_map {
	const char *name;
	unsigned int master;
	unsigned int index;
};

struct tegra_hsp_soc {
	const struct tegra_hsp_db_map *map;
};

struct tegra_hsp {
	const struct tegra_hsp_soc *soc;
	struct mbox_controller mbox;
	void __iomem *regs;
	unsigned int irq;
	unsigned int num_sm;
	unsigned int num_as;
	unsigned int num_ss;
	unsigned int num_db;
	unsigned int num_si;
	spinlock_t lock;

	struct list_head doorbells;
};

static inline struct tegra_hsp *
to_tegra_hsp(struct mbox_controller *mbox)
{
	return container_of(mbox, struct tegra_hsp, mbox);
}

static inline u32 tegra_hsp_readl(struct tegra_hsp *hsp, unsigned int offset)
{
	return readl(hsp->regs + offset);
}

static inline void tegra_hsp_writel(struct tegra_hsp *hsp, u32 value,
				    unsigned int offset)
{
	writel(value, hsp->regs + offset);
}

static inline u32 tegra_hsp_channel_readl(struct tegra_hsp_channel *channel,
					  unsigned int offset)
{
	return readl(channel->regs + offset);
}

static inline void tegra_hsp_channel_writel(struct tegra_hsp_channel *channel,
					    u32 value, unsigned int offset)
{
	writel(value, channel->regs + offset);
}

static bool tegra_hsp_doorbell_can_ring(struct tegra_hsp_doorbell *db)
{
	u32 value;

	value = tegra_hsp_channel_readl(&db->channel, HSP_DB_ENABLE);

	return (value & BIT(TEGRA_HSP_DB_MASTER_CCPLEX)) != 0;
}

static struct tegra_hsp_doorbell *
__tegra_hsp_doorbell_get(struct tegra_hsp *hsp, unsigned int master)
{
	struct tegra_hsp_doorbell *entry;

	list_for_each_entry(entry, &hsp->doorbells, list)
		if (entry->master == master)
			return entry;

	return NULL;
}

static struct tegra_hsp_doorbell *
tegra_hsp_doorbell_get(struct tegra_hsp *hsp, unsigned int master)
{
	struct tegra_hsp_doorbell *db;
	unsigned long flags;

	spin_lock_irqsave(&hsp->lock, flags);
	db = __tegra_hsp_doorbell_get(hsp, master);
	spin_unlock_irqrestore(&hsp->lock, flags);

	return db;
}

static irqreturn_t tegra_hsp_doorbell_irq(int irq, void *data)
{
	struct tegra_hsp *hsp = data;
	struct tegra_hsp_doorbell *db;
	unsigned long master, value;

	db = tegra_hsp_doorbell_get(hsp, TEGRA_HSP_DB_MASTER_CCPLEX);
	if (!db)
		return IRQ_NONE;

	value = tegra_hsp_channel_readl(&db->channel, HSP_DB_PENDING);
	tegra_hsp_channel_writel(&db->channel, value, HSP_DB_PENDING);

	spin_lock(&hsp->lock);

	for_each_set_bit(master, &value, hsp->mbox.num_chans) {
		struct tegra_hsp_doorbell *db;

		db = __tegra_hsp_doorbell_get(hsp, master);
		/*
		 * Depending on the bootloader chain, the CCPLEX doorbell will
		 * have some doorbells enabled, which means that requesting an
		 * interrupt will immediately fire.
		 *
		 * In that case, db->channel.chan will still be NULL here and
		 * cause a crash if not properly guarded.
		 *
		 * It remains to be seen if ignoring the doorbell in that case
		 * is the correct solution.
		 */
		if (db && db->channel.chan)
			mbox_chan_received_data(db->channel.chan, NULL);
	}

	spin_unlock(&hsp->lock);

	return IRQ_HANDLED;
}

static struct tegra_hsp_channel *
tegra_hsp_doorbell_create(struct tegra_hsp *hsp, const char *name,
			  unsigned int master, unsigned int index)
{
	struct tegra_hsp_doorbell *db;
	unsigned int offset;
	unsigned long flags;

	db = kzalloc(sizeof(*db), GFP_KERNEL);
	if (!db)
		return ERR_PTR(-ENOMEM);

	offset = (1 + (hsp->num_sm / 2) + hsp->num_ss + hsp->num_as) << 16;
	offset += index * 0x100;

	db->channel.regs = hsp->regs + offset;
	db->channel.hsp = hsp;

	db->name = kstrdup_const(name, GFP_KERNEL);
	db->master = master;
	db->index = index;

	spin_lock_irqsave(&hsp->lock, flags);
	list_add_tail(&db->list, &hsp->doorbells);
	spin_unlock_irqrestore(&hsp->lock, flags);

	return &db->channel;
}

static void __tegra_hsp_doorbell_destroy(struct tegra_hsp_doorbell *db)
{
	list_del(&db->list);
	kfree_const(db->name);
	kfree(db);
}

static int tegra_hsp_doorbell_send_data(struct mbox_chan *chan, void *data)
{
	struct tegra_hsp_doorbell *db = chan->con_priv;

	tegra_hsp_channel_writel(&db->channel, 1, HSP_DB_TRIGGER);

	return 0;
}

static int tegra_hsp_doorbell_startup(struct mbox_chan *chan)
{
	struct tegra_hsp_doorbell *db = chan->con_priv;
	struct tegra_hsp *hsp = db->channel.hsp;
	struct tegra_hsp_doorbell *ccplex;
	unsigned long flags;
	u32 value;

	if (db->master >= hsp->mbox.num_chans) {
		dev_err(hsp->mbox.dev,
			"invalid master ID %u for HSP channel\n",
			db->master);
		return -EINVAL;
	}

	ccplex = tegra_hsp_doorbell_get(hsp, TEGRA_HSP_DB_MASTER_CCPLEX);
	if (!ccplex)
		return -ENODEV;

	if (!tegra_hsp_doorbell_can_ring(db))
		return -ENODEV;

	spin_lock_irqsave(&hsp->lock, flags);

	value = tegra_hsp_channel_readl(&ccplex->channel, HSP_DB_ENABLE);
	value |= BIT(db->master);
	tegra_hsp_channel_writel(&ccplex->channel, value, HSP_DB_ENABLE);

	spin_unlock_irqrestore(&hsp->lock, flags);

	return 0;
}

static void tegra_hsp_doorbell_shutdown(struct mbox_chan *chan)
{
	struct tegra_hsp_doorbell *db = chan->con_priv;
	struct tegra_hsp *hsp = db->channel.hsp;
	struct tegra_hsp_doorbell *ccplex;
	unsigned long flags;
	u32 value;

	ccplex = tegra_hsp_doorbell_get(hsp, TEGRA_HSP_DB_MASTER_CCPLEX);
	if (!ccplex)
		return;

	spin_lock_irqsave(&hsp->lock, flags);

	value = tegra_hsp_channel_readl(&ccplex->channel, HSP_DB_ENABLE);
	value &= ~BIT(db->master);
	tegra_hsp_channel_writel(&ccplex->channel, value, HSP_DB_ENABLE);

	spin_unlock_irqrestore(&hsp->lock, flags);
}

static const struct mbox_chan_ops tegra_hsp_doorbell_ops = {
	.send_data = tegra_hsp_doorbell_send_data,
	.startup = tegra_hsp_doorbell_startup,
	.shutdown = tegra_hsp_doorbell_shutdown,
};

static struct mbox_chan *of_tegra_hsp_xlate(struct mbox_controller *mbox,
					    const struct of_phandle_args *args)
{
	struct tegra_hsp_channel *channel = ERR_PTR(-ENODEV);
	struct tegra_hsp *hsp = to_tegra_hsp(mbox);
	unsigned int type = args->args[0];
	unsigned int master = args->args[1];
	struct tegra_hsp_doorbell *db;
	struct mbox_chan *chan;
	unsigned long flags;
	unsigned int i;

	switch (type) {
	case TEGRA_HSP_MBOX_TYPE_DB:
		db = tegra_hsp_doorbell_get(hsp, master);
		if (db)
			channel = &db->channel;

		break;

	default:
		break;
	}

	if (IS_ERR(channel))
		return ERR_CAST(channel);

	spin_lock_irqsave(&hsp->lock, flags);

	for (i = 0; i < hsp->mbox.num_chans; i++) {
		chan = &hsp->mbox.chans[i];
		if (!chan->con_priv) {
			chan->con_priv = channel;
			channel->chan = chan;
			break;
		}

		chan = NULL;
	}

	spin_unlock_irqrestore(&hsp->lock, flags);

	return chan ?: ERR_PTR(-EBUSY);
}

static void tegra_hsp_remove_doorbells(struct tegra_hsp *hsp)
{
	struct tegra_hsp_doorbell *db, *tmp;
	unsigned long flags;

	spin_lock_irqsave(&hsp->lock, flags);

	list_for_each_entry_safe(db, tmp, &hsp->doorbells, list)
		__tegra_hsp_doorbell_destroy(db);

	spin_unlock_irqrestore(&hsp->lock, flags);
}

static int tegra_hsp_add_doorbells(struct tegra_hsp *hsp)
{
	const struct tegra_hsp_db_map *map = hsp->soc->map;
	struct tegra_hsp_channel *channel;

	while (map->name) {
		channel = tegra_hsp_doorbell_create(hsp, map->name,
						    map->master, map->index);
		if (IS_ERR(channel)) {
			tegra_hsp_remove_doorbells(hsp);
			return PTR_ERR(channel);
		}

		map++;
	}

	return 0;
}

static int tegra_hsp_probe(struct platform_device *pdev)
{
	struct tegra_hsp *hsp;
	struct resource *res;
	u32 value;
	int err;

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

	hsp->soc = of_device_get_match_data(&pdev->dev);
	INIT_LIST_HEAD(&hsp->doorbells);
	spin_lock_init(&hsp->lock);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	hsp->regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(hsp->regs))
		return PTR_ERR(hsp->regs);

	value = tegra_hsp_readl(hsp, HSP_INT_DIMENSIONING);
	hsp->num_sm = (value >> HSP_nSM_SHIFT) & HSP_nINT_MASK;
	hsp->num_ss = (value >> HSP_nSS_SHIFT) & HSP_nINT_MASK;
	hsp->num_as = (value >> HSP_nAS_SHIFT) & HSP_nINT_MASK;
	hsp->num_db = (value >> HSP_nDB_SHIFT) & HSP_nINT_MASK;
	hsp->num_si = (value >> HSP_nSI_SHIFT) & HSP_nINT_MASK;

	err = platform_get_irq_byname(pdev, "doorbell");
	if (err < 0) {
		dev_err(&pdev->dev, "failed to get doorbell IRQ: %d\n", err);
		return err;
	}

	hsp->irq = err;

	hsp->mbox.of_xlate = of_tegra_hsp_xlate;
	hsp->mbox.num_chans = 32;
	hsp->mbox.dev = &pdev->dev;
	hsp->mbox.txdone_irq = false;
	hsp->mbox.txdone_poll = false;
	hsp->mbox.ops = &tegra_hsp_doorbell_ops;

	hsp->mbox.chans = devm_kcalloc(&pdev->dev, hsp->mbox.num_chans,
					sizeof(*hsp->mbox.chans),
					GFP_KERNEL);
	if (!hsp->mbox.chans)
		return -ENOMEM;

	err = tegra_hsp_add_doorbells(hsp);
	if (err < 0) {
		dev_err(&pdev->dev, "failed to add doorbells: %d\n", err);
		return err;
	}

	platform_set_drvdata(pdev, hsp);

	err = mbox_controller_register(&hsp->mbox);
	if (err) {
		dev_err(&pdev->dev, "failed to register mailbox: %d\n", err);
		tegra_hsp_remove_doorbells(hsp);
		return err;
	}

	err = devm_request_irq(&pdev->dev, hsp->irq, tegra_hsp_doorbell_irq,
			       IRQF_NO_SUSPEND, dev_name(&pdev->dev), hsp);
	if (err < 0) {
		dev_err(&pdev->dev, "failed to request IRQ#%u: %d\n",
			hsp->irq, err);
		return err;
	}

	return 0;
}

static int tegra_hsp_remove(struct platform_device *pdev)
{
	struct tegra_hsp *hsp = platform_get_drvdata(pdev);

	mbox_controller_unregister(&hsp->mbox);
	tegra_hsp_remove_doorbells(hsp);

	return 0;
}

static const struct tegra_hsp_db_map tegra186_hsp_db_map[] = {
	{ "ccplex", TEGRA_HSP_DB_MASTER_CCPLEX, HSP_DB_CCPLEX, },
	{ "bpmp",   TEGRA_HSP_DB_MASTER_BPMP,   HSP_DB_BPMP,   },
	{ /* sentinel */ }
};

static const struct tegra_hsp_soc tegra186_hsp_soc = {
	.map = tegra186_hsp_db_map,
};

static const struct of_device_id tegra_hsp_match[] = {
	{ .compatible = "nvidia,tegra186-hsp", .data = &tegra186_hsp_soc },
	{ }
};

static struct platform_driver tegra_hsp_driver = {
	.driver = {
		.name = "tegra-hsp",
		.of_match_table = tegra_hsp_match,
	},
	.probe = tegra_hsp_probe,
	.remove = tegra_hsp_remove,
};

static int __init tegra_hsp_init(void)
{
	return platform_driver_register(&tegra_hsp_driver);
}
core_initcall(tegra_hsp_init);