summaryrefslogtreecommitdiff
path: root/drivers/dma/fsl-edma.c
blob: 76cbf54aec58f1d73639ffb8dbc6d31f38244797 (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * drivers/dma/fsl-edma.c
 *
 * Copyright 2013-2014 Freescale Semiconductor, Inc.
 *
 * Driver for the Freescale eDMA engine with flexible channel multiplexing
 * capability for DMA request sources. The eDMA block can be found on some
 * Vybrid and Layerscape SoCs.
 */

#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_dma.h>
#include <linux/dma-mapping.h>

#include "fsl-edma-common.h"

static void fsl_edma_synchronize(struct dma_chan *chan)
{
	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);

	vchan_synchronize(&fsl_chan->vchan);
}

static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
{
	struct fsl_edma_engine *fsl_edma = dev_id;
	unsigned int intr, ch;
	struct edma_regs *regs = &fsl_edma->regs;
	struct fsl_edma_chan *fsl_chan;

	intr = edma_readl(fsl_edma, regs->intl);
	if (!intr)
		return IRQ_NONE;

	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
		if (intr & (0x1 << ch)) {
			edma_writeb(fsl_edma, EDMA_CINT_CINT(ch), regs->cint);

			fsl_chan = &fsl_edma->chans[ch];

			spin_lock(&fsl_chan->vchan.lock);

			if (!fsl_chan->edesc) {
				/* terminate_all called before */
				spin_unlock(&fsl_chan->vchan.lock);
				continue;
			}

			if (!fsl_chan->edesc->iscyclic) {
				list_del(&fsl_chan->edesc->vdesc.node);
				vchan_cookie_complete(&fsl_chan->edesc->vdesc);
				fsl_chan->edesc = NULL;
				fsl_chan->status = DMA_COMPLETE;
				fsl_chan->idle = true;
			} else {
				vchan_cyclic_callback(&fsl_chan->edesc->vdesc);
			}

			if (!fsl_chan->edesc)
				fsl_edma_xfer_desc(fsl_chan);

			spin_unlock(&fsl_chan->vchan.lock);
		}
	}
	return IRQ_HANDLED;
}

static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
{
	struct fsl_edma_engine *fsl_edma = dev_id;
	unsigned int err, ch;
	struct edma_regs *regs = &fsl_edma->regs;

	err = edma_readl(fsl_edma, regs->errl);
	if (!err)
		return IRQ_NONE;

	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
		if (err & (0x1 << ch)) {
			fsl_edma_disable_request(&fsl_edma->chans[ch]);
			edma_writeb(fsl_edma, EDMA_CERR_CERR(ch), regs->cerr);
			fsl_edma->chans[ch].status = DMA_ERROR;
			fsl_edma->chans[ch].idle = true;
		}
	}
	return IRQ_HANDLED;
}

static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
{
	if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
		return IRQ_HANDLED;

	return fsl_edma_err_handler(irq, dev_id);
}

static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
		struct of_dma *ofdma)
{
	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
	struct dma_chan *chan, *_chan;
	struct fsl_edma_chan *fsl_chan;
	u32 dmamux_nr = fsl_edma->drvdata->dmamuxs;
	unsigned long chans_per_mux = fsl_edma->n_chans / dmamux_nr;

	if (dma_spec->args_count != 2)
		return NULL;

	mutex_lock(&fsl_edma->fsl_edma_mutex);
	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
		if (chan->client_count)
			continue;
		if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
			chan = dma_get_slave_channel(chan);
			if (chan) {
				chan->device->privatecnt++;
				fsl_chan = to_fsl_edma_chan(chan);
				fsl_chan->slave_id = dma_spec->args[1];
				fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id,
						true);
				mutex_unlock(&fsl_edma->fsl_edma_mutex);
				return chan;
			}
		}
	}
	mutex_unlock(&fsl_edma->fsl_edma_mutex);
	return NULL;
}

static int
fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
{
	int ret;

	fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
	if (fsl_edma->txirq < 0)
		return fsl_edma->txirq;

	fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
	if (fsl_edma->errirq < 0)
		return fsl_edma->errirq;

	if (fsl_edma->txirq == fsl_edma->errirq) {
		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
				fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
		if (ret) {
			dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
			return ret;
		}
	} else {
		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
				fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
		if (ret) {
			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
			return ret;
		}

		ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
				fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
		if (ret) {
			dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
			return ret;
		}
	}

	return 0;
}

static int
fsl_edma2_irq_init(struct platform_device *pdev,
		   struct fsl_edma_engine *fsl_edma)
{
	int i, ret, irq;
	int count;

	count = platform_irq_count(pdev);
	dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count);
	if (count <= 2) {
		dev_err(&pdev->dev, "Interrupts in DTS not correct.\n");
		return -EINVAL;
	}
	/*
	 * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp.
	 * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17...
	 * For now, just simply request irq without IRQF_SHARED flag, since 16
	 * channels are enough on i.mx7ulp whose M4 domain own some peripherals.
	 */
	for (i = 0; i < count; i++) {
		irq = platform_get_irq(pdev, i);
		if (irq < 0)
			return -ENXIO;

		sprintf(fsl_edma->chans[i].chan_name, "eDMA2-CH%02d", i);

		/* The last IRQ is for eDMA err */
		if (i == count - 1)
			ret = devm_request_irq(&pdev->dev, irq,
						fsl_edma_err_handler,
						0, "eDMA2-ERR", fsl_edma);
		else
			ret = devm_request_irq(&pdev->dev, irq,
						fsl_edma_tx_handler, 0,
						fsl_edma->chans[i].chan_name,
						fsl_edma);
		if (ret)
			return ret;
	}

	return 0;
}

static void fsl_edma_irq_exit(
		struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
{
	if (fsl_edma->txirq == fsl_edma->errirq) {
		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
	} else {
		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
		devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma);
	}
}

static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks)
{
	int i;

	for (i = 0; i < nr_clocks; i++)
		clk_disable_unprepare(fsl_edma->muxclk[i]);
}

static struct fsl_edma_drvdata vf610_data = {
	.version = v1,
	.dmamuxs = DMAMUX_NR,
	.setup_irq = fsl_edma_irq_init,
};

static struct fsl_edma_drvdata ls1028a_data = {
	.version = v1,
	.dmamuxs = DMAMUX_NR,
	.mux_swap = true,
	.setup_irq = fsl_edma_irq_init,
};

static struct fsl_edma_drvdata imx7ulp_data = {
	.version = v3,
	.dmamuxs = 1,
	.has_dmaclk = true,
	.setup_irq = fsl_edma2_irq_init,
};

static const struct of_device_id fsl_edma_dt_ids[] = {
	{ .compatible = "fsl,vf610-edma", .data = &vf610_data},
	{ .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data},
	{ .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data},
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);

static int fsl_edma_probe(struct platform_device *pdev)
{
	const struct of_device_id *of_id =
			of_match_device(fsl_edma_dt_ids, &pdev->dev);
	struct device_node *np = pdev->dev.of_node;
	struct fsl_edma_engine *fsl_edma;
	const struct fsl_edma_drvdata *drvdata = NULL;
	struct fsl_edma_chan *fsl_chan;
	struct edma_regs *regs;
	struct resource *res;
	int len, chans;
	int ret, i;

	if (of_id)
		drvdata = of_id->data;
	if (!drvdata) {
		dev_err(&pdev->dev, "unable to find driver data\n");
		return -EINVAL;
	}

	ret = of_property_read_u32(np, "dma-channels", &chans);
	if (ret) {
		dev_err(&pdev->dev, "Can't get dma-channels.\n");
		return ret;
	}

	len = sizeof(*fsl_edma) + sizeof(*fsl_chan) * chans;
	fsl_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
	if (!fsl_edma)
		return -ENOMEM;

	fsl_edma->drvdata = drvdata;
	fsl_edma->n_chans = chans;
	mutex_init(&fsl_edma->fsl_edma_mutex);

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

	fsl_edma_setup_regs(fsl_edma);
	regs = &fsl_edma->regs;

	if (drvdata->has_dmaclk) {
		fsl_edma->dmaclk = devm_clk_get(&pdev->dev, "dma");
		if (IS_ERR(fsl_edma->dmaclk)) {
			dev_err(&pdev->dev, "Missing DMA block clock.\n");
			return PTR_ERR(fsl_edma->dmaclk);
		}

		ret = clk_prepare_enable(fsl_edma->dmaclk);
		if (ret) {
			dev_err(&pdev->dev, "DMA clk block failed.\n");
			return ret;
		}
	}

	for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) {
		char clkname[32];

		res = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
		fsl_edma->muxbase[i] = devm_ioremap_resource(&pdev->dev, res);
		if (IS_ERR(fsl_edma->muxbase[i])) {
			/* on error: disable all previously enabled clks */
			fsl_disable_clocks(fsl_edma, i);
			return PTR_ERR(fsl_edma->muxbase[i]);
		}

		sprintf(clkname, "dmamux%d", i);
		fsl_edma->muxclk[i] = devm_clk_get(&pdev->dev, clkname);
		if (IS_ERR(fsl_edma->muxclk[i])) {
			dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
			/* on error: disable all previously enabled clks */
			fsl_disable_clocks(fsl_edma, i);
			return PTR_ERR(fsl_edma->muxclk[i]);
		}

		ret = clk_prepare_enable(fsl_edma->muxclk[i]);
		if (ret)
			/* on error: disable all previously enabled clks */
			fsl_disable_clocks(fsl_edma, i);

	}

	fsl_edma->big_endian = of_property_read_bool(np, "big-endian");

	INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
	for (i = 0; i < fsl_edma->n_chans; i++) {
		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];

		fsl_chan->edma = fsl_edma;
		fsl_chan->pm_state = RUNNING;
		fsl_chan->slave_id = 0;
		fsl_chan->idle = true;
		fsl_chan->dma_dir = DMA_NONE;
		fsl_chan->vchan.desc_free = fsl_edma_free_desc;
		vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);

		edma_writew(fsl_edma, 0x0, &regs->tcd[i].csr);
		fsl_edma_chan_mux(fsl_chan, 0, false);
	}

	edma_writel(fsl_edma, ~0, regs->intl);
	ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
	if (ret)
		return ret;

	dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
	dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
	dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
	dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);

	fsl_edma->dma_dev.dev = &pdev->dev;
	fsl_edma->dma_dev.device_alloc_chan_resources
		= fsl_edma_alloc_chan_resources;
	fsl_edma->dma_dev.device_free_chan_resources
		= fsl_edma_free_chan_resources;
	fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
	fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
	fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
	fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
	fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
	fsl_edma->dma_dev.device_pause = fsl_edma_pause;
	fsl_edma->dma_dev.device_resume = fsl_edma_resume;
	fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
	fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize;
	fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;

	fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
	fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
	fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);

	fsl_edma->dma_dev.copy_align = DMAENGINE_ALIGN_32_BYTES;
	/* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
	dma_set_max_seg_size(fsl_edma->dma_dev.dev, 0x3fff);

	platform_set_drvdata(pdev, fsl_edma);

	ret = dma_async_device_register(&fsl_edma->dma_dev);
	if (ret) {
		dev_err(&pdev->dev,
			"Can't register Freescale eDMA engine. (%d)\n", ret);
		fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
		return ret;
	}

	ret = of_dma_controller_register(np, fsl_edma_xlate, fsl_edma);
	if (ret) {
		dev_err(&pdev->dev,
			"Can't register Freescale eDMA of_dma. (%d)\n", ret);
		dma_async_device_unregister(&fsl_edma->dma_dev);
		fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
		return ret;
	}

	/* enable round robin arbitration */
	edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);

	return 0;
}

static int fsl_edma_remove(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);

	fsl_edma_irq_exit(pdev, fsl_edma);
	fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
	of_dma_controller_free(np);
	dma_async_device_unregister(&fsl_edma->dma_dev);
	fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);

	return 0;
}

static int fsl_edma_suspend_late(struct device *dev)
{
	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
	struct fsl_edma_chan *fsl_chan;
	unsigned long flags;
	int i;

	for (i = 0; i < fsl_edma->n_chans; i++) {
		fsl_chan = &fsl_edma->chans[i];
		spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
		/* Make sure chan is idle or will force disable. */
		if (unlikely(!fsl_chan->idle)) {
			dev_warn(dev, "WARN: There is non-idle channel.");
			fsl_edma_disable_request(fsl_chan);
			fsl_edma_chan_mux(fsl_chan, 0, false);
		}

		fsl_chan->pm_state = SUSPENDED;
		spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
	}

	return 0;
}

static int fsl_edma_resume_early(struct device *dev)
{
	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
	struct fsl_edma_chan *fsl_chan;
	struct edma_regs *regs = &fsl_edma->regs;
	int i;

	for (i = 0; i < fsl_edma->n_chans; i++) {
		fsl_chan = &fsl_edma->chans[i];
		fsl_chan->pm_state = RUNNING;
		edma_writew(fsl_edma, 0x0, &regs->tcd[i].csr);
		if (fsl_chan->slave_id != 0)
			fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
	}

	edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);

	return 0;
}

/*
 * eDMA provides the service to others, so it should be suspend late
 * and resume early. When eDMA suspend, all of the clients should stop
 * the DMA data transmission and let the channel idle.
 */
static const struct dev_pm_ops fsl_edma_pm_ops = {
	.suspend_late   = fsl_edma_suspend_late,
	.resume_early   = fsl_edma_resume_early,
};

static struct platform_driver fsl_edma_driver = {
	.driver		= {
		.name	= "fsl-edma",
		.of_match_table = fsl_edma_dt_ids,
		.pm     = &fsl_edma_pm_ops,
	},
	.probe          = fsl_edma_probe,
	.remove		= fsl_edma_remove,
};

static int __init fsl_edma_init(void)
{
	return platform_driver_register(&fsl_edma_driver);
}
subsys_initcall(fsl_edma_init);

static void __exit fsl_edma_exit(void)
{
	platform_driver_unregister(&fsl_edma_driver);
}
module_exit(fsl_edma_exit);

MODULE_ALIAS("platform:fsl-edma");
MODULE_DESCRIPTION("Freescale eDMA engine driver");
MODULE_LICENSE("GPL v2");