summaryrefslogtreecommitdiff
path: root/drivers/dma/sh/sudmac.c
blob: b5b7e54ac845b6a4a020abcfd4210fef4da934f9 (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
/*
 * Renesas SUDMAC support
 *
 * Copyright (C) 2013 Renesas Solutions Corp.
 *
 * based on drivers/dma/sh/shdma.c:
 * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
 * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
 * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
 * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
 *
 * This is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 */

#include <linux/dmaengine.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/sudmac.h>

struct sudmac_chan {
	struct shdma_chan shdma_chan;
	void __iomem *base;
	char dev_id[16];	/* unique name per DMAC of channel */

	u32 offset;		/* for CFG, BA, BBC, CA, CBC, DEN */
	u32 cfg;
	u32 dint_end_bit;
};

struct sudmac_device {
	struct shdma_dev shdma_dev;
	struct sudmac_pdata *pdata;
	void __iomem *chan_reg;
};

struct sudmac_regs {
	u32 base_addr;
	u32 base_byte_count;
};

struct sudmac_desc {
	struct sudmac_regs hw;
	struct shdma_desc shdma_desc;
};

#define to_chan(schan) container_of(schan, struct sudmac_chan, shdma_chan)
#define to_desc(sdesc) container_of(sdesc, struct sudmac_desc, shdma_desc)
#define to_sdev(sc) container_of(sc->shdma_chan.dma_chan.device, \
				 struct sudmac_device, shdma_dev.dma_dev)

/* SUDMAC register */
#define SUDMAC_CH0CFG		0x00
#define SUDMAC_CH0BA		0x10
#define SUDMAC_CH0BBC		0x18
#define SUDMAC_CH0CA		0x20
#define SUDMAC_CH0CBC		0x28
#define SUDMAC_CH0DEN		0x30
#define SUDMAC_DSTSCLR		0x38
#define SUDMAC_DBUFCTRL		0x3C
#define SUDMAC_DINTCTRL		0x40
#define SUDMAC_DINTSTS		0x44
#define SUDMAC_DINTSTSCLR	0x48
#define SUDMAC_CH0SHCTRL	0x50

/* Definitions for the sudmac_channel.config */
#define SUDMAC_SENDBUFM	0x1000 /* b12: Transmit Buffer Mode */
#define SUDMAC_RCVENDM	0x0100 /* b8: Receive Data Transfer End Mode */
#define SUDMAC_LBA_WAIT	0x0030 /* b5-4: Local Bus Access Wait */

/* Definitions for the sudmac_channel.dint_end_bit */
#define SUDMAC_CH1ENDE	0x0002 /* b1: Ch1 DMA Transfer End Int Enable */
#define SUDMAC_CH0ENDE	0x0001 /* b0: Ch0 DMA Transfer End Int Enable */

#define SUDMAC_DRV_NAME "sudmac"

static void sudmac_writel(struct sudmac_chan *sc, u32 data, u32 reg)
{
	iowrite32(data, sc->base + reg);
}

static u32 sudmac_readl(struct sudmac_chan *sc, u32 reg)
{
	return ioread32(sc->base + reg);
}

static bool sudmac_is_busy(struct sudmac_chan *sc)
{
	u32 den = sudmac_readl(sc, SUDMAC_CH0DEN + sc->offset);

	if (den)
		return true; /* working */

	return false; /* waiting */
}

static void sudmac_set_reg(struct sudmac_chan *sc, struct sudmac_regs *hw,
			   struct shdma_desc *sdesc)
{
	sudmac_writel(sc, sc->cfg, SUDMAC_CH0CFG + sc->offset);
	sudmac_writel(sc, hw->base_addr, SUDMAC_CH0BA + sc->offset);
	sudmac_writel(sc, hw->base_byte_count, SUDMAC_CH0BBC + sc->offset);
}

static void sudmac_start(struct sudmac_chan *sc)
{
	u32 dintctrl = sudmac_readl(sc, SUDMAC_DINTCTRL);

	sudmac_writel(sc, dintctrl | sc->dint_end_bit, SUDMAC_DINTCTRL);
	sudmac_writel(sc, 1, SUDMAC_CH0DEN + sc->offset);
}

static void sudmac_start_xfer(struct shdma_chan *schan,
			      struct shdma_desc *sdesc)
{
	struct sudmac_chan *sc = to_chan(schan);
	struct sudmac_desc *sd = to_desc(sdesc);

	sudmac_set_reg(sc, &sd->hw, sdesc);
	sudmac_start(sc);
}

static bool sudmac_channel_busy(struct shdma_chan *schan)
{
	struct sudmac_chan *sc = to_chan(schan);

	return sudmac_is_busy(sc);
}

static void sudmac_setup_xfer(struct shdma_chan *schan, int slave_id)
{
}

static const struct sudmac_slave_config *sudmac_find_slave(
	struct sudmac_chan *sc, int slave_id)
{
	struct sudmac_device *sdev = to_sdev(sc);
	struct sudmac_pdata *pdata = sdev->pdata;
	const struct sudmac_slave_config *cfg;
	int i;

	for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
		if (cfg->slave_id == slave_id)
			return cfg;

	return NULL;
}

static int sudmac_set_slave(struct shdma_chan *schan, int slave_id,
			    dma_addr_t slave_addr, bool try)
{
	struct sudmac_chan *sc = to_chan(schan);
	const struct sudmac_slave_config *cfg = sudmac_find_slave(sc, slave_id);

	if (!cfg)
		return -ENODEV;

	return 0;
}

static inline void sudmac_dma_halt(struct sudmac_chan *sc)
{
	u32 dintctrl = sudmac_readl(sc, SUDMAC_DINTCTRL);

	sudmac_writel(sc, 0, SUDMAC_CH0DEN + sc->offset);
	sudmac_writel(sc, dintctrl & ~sc->dint_end_bit, SUDMAC_DINTCTRL);
	sudmac_writel(sc, sc->dint_end_bit, SUDMAC_DINTSTSCLR);
}

static int sudmac_desc_setup(struct shdma_chan *schan,
			     struct shdma_desc *sdesc,
			     dma_addr_t src, dma_addr_t dst, size_t *len)
{
	struct sudmac_chan *sc = to_chan(schan);
	struct sudmac_desc *sd = to_desc(sdesc);

	dev_dbg(sc->shdma_chan.dev, "%s: src=%pad, dst=%pad, len=%zu\n",
		__func__, &src, &dst, *len);

	if (*len > schan->max_xfer_len)
		*len = schan->max_xfer_len;

	if (dst)
		sd->hw.base_addr = dst;
	else if (src)
		sd->hw.base_addr = src;
	sd->hw.base_byte_count = *len;

	return 0;
}

static void sudmac_halt(struct shdma_chan *schan)
{
	struct sudmac_chan *sc = to_chan(schan);

	sudmac_dma_halt(sc);
}

static bool sudmac_chan_irq(struct shdma_chan *schan, int irq)
{
	struct sudmac_chan *sc = to_chan(schan);
	u32 dintsts = sudmac_readl(sc, SUDMAC_DINTSTS);

	if (!(dintsts & sc->dint_end_bit))
		return false;

	/* DMA stop */
	sudmac_dma_halt(sc);

	return true;
}

static size_t sudmac_get_partial(struct shdma_chan *schan,
				 struct shdma_desc *sdesc)
{
	struct sudmac_chan *sc = to_chan(schan);
	struct sudmac_desc *sd = to_desc(sdesc);
	u32 current_byte_count = sudmac_readl(sc, SUDMAC_CH0CBC + sc->offset);

	return sd->hw.base_byte_count - current_byte_count;
}

static bool sudmac_desc_completed(struct shdma_chan *schan,
				  struct shdma_desc *sdesc)
{
	struct sudmac_chan *sc = to_chan(schan);
	struct sudmac_desc *sd = to_desc(sdesc);
	u32 current_addr = sudmac_readl(sc, SUDMAC_CH0CA + sc->offset);

	return sd->hw.base_addr + sd->hw.base_byte_count == current_addr;
}

static int sudmac_chan_probe(struct sudmac_device *su_dev, int id, int irq,
			     unsigned long flags)
{
	struct shdma_dev *sdev = &su_dev->shdma_dev;
	struct platform_device *pdev = to_platform_device(sdev->dma_dev.dev);
	struct sudmac_chan *sc;
	struct shdma_chan *schan;
	int err;

	sc = devm_kzalloc(&pdev->dev, sizeof(struct sudmac_chan), GFP_KERNEL);
	if (!sc) {
		dev_err(sdev->dma_dev.dev,
			"No free memory for allocating dma channels!\n");
		return -ENOMEM;
	}

	schan = &sc->shdma_chan;
	schan->max_xfer_len = 64 * 1024 * 1024 - 1;

	shdma_chan_probe(sdev, schan, id);

	sc->base = su_dev->chan_reg;

	/* get platform_data */
	sc->offset = su_dev->pdata->channel->offset;
	if (su_dev->pdata->channel->config & SUDMAC_TX_BUFFER_MODE)
		sc->cfg |= SUDMAC_SENDBUFM;
	if (su_dev->pdata->channel->config & SUDMAC_RX_END_MODE)
		sc->cfg |= SUDMAC_RCVENDM;
	sc->cfg |= (su_dev->pdata->channel->wait << 4) & SUDMAC_LBA_WAIT;

	if (su_dev->pdata->channel->dint_end_bit & SUDMAC_DMA_BIT_CH0)
		sc->dint_end_bit |= SUDMAC_CH0ENDE;
	if (su_dev->pdata->channel->dint_end_bit & SUDMAC_DMA_BIT_CH1)
		sc->dint_end_bit |= SUDMAC_CH1ENDE;

	/* set up channel irq */
	if (pdev->id >= 0)
		snprintf(sc->dev_id, sizeof(sc->dev_id), "sudmac%d.%d",
			 pdev->id, id);
	else
		snprintf(sc->dev_id, sizeof(sc->dev_id), "sudmac%d", id);

	err = shdma_request_irq(schan, irq, flags, sc->dev_id);
	if (err) {
		dev_err(sdev->dma_dev.dev,
			"DMA channel %d request_irq failed %d\n", id, err);
		goto err_no_irq;
	}

	return 0;

err_no_irq:
	/* remove from dmaengine device node */
	shdma_chan_remove(schan);
	return err;
}

static void sudmac_chan_remove(struct sudmac_device *su_dev)
{
	struct dma_device *dma_dev = &su_dev->shdma_dev.dma_dev;
	struct shdma_chan *schan;
	int i;

	shdma_for_each_chan(schan, &su_dev->shdma_dev, i) {
		BUG_ON(!schan);

		shdma_chan_remove(schan);
	}
	dma_dev->chancnt = 0;
}

static dma_addr_t sudmac_slave_addr(struct shdma_chan *schan)
{
	/* SUDMAC doesn't need the address */
	return 0;
}

static struct shdma_desc *sudmac_embedded_desc(void *buf, int i)
{
	return &((struct sudmac_desc *)buf)[i].shdma_desc;
}

static const struct shdma_ops sudmac_shdma_ops = {
	.desc_completed = sudmac_desc_completed,
	.halt_channel = sudmac_halt,
	.channel_busy = sudmac_channel_busy,
	.slave_addr = sudmac_slave_addr,
	.desc_setup = sudmac_desc_setup,
	.set_slave = sudmac_set_slave,
	.setup_xfer = sudmac_setup_xfer,
	.start_xfer = sudmac_start_xfer,
	.embedded_desc = sudmac_embedded_desc,
	.chan_irq = sudmac_chan_irq,
	.get_partial = sudmac_get_partial,
};

static int sudmac_probe(struct platform_device *pdev)
{
	struct sudmac_pdata *pdata = dev_get_platdata(&pdev->dev);
	int err, i;
	struct sudmac_device *su_dev;
	struct dma_device *dma_dev;
	struct resource *chan, *irq_res;

	/* get platform data */
	if (!pdata)
		return -ENODEV;

	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	if (!irq_res)
		return -ENODEV;

	err = -ENOMEM;
	su_dev = devm_kzalloc(&pdev->dev, sizeof(struct sudmac_device),
			      GFP_KERNEL);
	if (!su_dev) {
		dev_err(&pdev->dev, "Not enough memory\n");
		return err;
	}

	dma_dev = &su_dev->shdma_dev.dma_dev;

	chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	su_dev->chan_reg = devm_ioremap_resource(&pdev->dev, chan);
	if (IS_ERR(su_dev->chan_reg))
		return PTR_ERR(su_dev->chan_reg);

	dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);

	su_dev->shdma_dev.ops = &sudmac_shdma_ops;
	su_dev->shdma_dev.desc_size = sizeof(struct sudmac_desc);
	err = shdma_init(&pdev->dev, &su_dev->shdma_dev, pdata->channel_num);
	if (err < 0)
		return err;

	/* platform data */
	su_dev->pdata = dev_get_platdata(&pdev->dev);

	platform_set_drvdata(pdev, su_dev);

	/* Create DMA Channel */
	for (i = 0; i < pdata->channel_num; i++) {
		err = sudmac_chan_probe(su_dev, i, irq_res->start, IRQF_SHARED);
		if (err)
			goto chan_probe_err;
	}

	err = dma_async_device_register(&su_dev->shdma_dev.dma_dev);
	if (err < 0)
		goto chan_probe_err;

	return err;

chan_probe_err:
	sudmac_chan_remove(su_dev);

	shdma_cleanup(&su_dev->shdma_dev);

	return err;
}

static int sudmac_remove(struct platform_device *pdev)
{
	struct sudmac_device *su_dev = platform_get_drvdata(pdev);
	struct dma_device *dma_dev = &su_dev->shdma_dev.dma_dev;

	dma_async_device_unregister(dma_dev);
	sudmac_chan_remove(su_dev);
	shdma_cleanup(&su_dev->shdma_dev);

	return 0;
}

static struct platform_driver sudmac_driver = {
	.driver		= {
		.owner	= THIS_MODULE,
		.name	= SUDMAC_DRV_NAME,
	},
	.probe		= sudmac_probe,
	.remove		= sudmac_remove,
};
module_platform_driver(sudmac_driver);

MODULE_AUTHOR("Yoshihiro Shimoda");
MODULE_DESCRIPTION("Renesas SUDMAC driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" SUDMAC_DRV_NAME);