xref: /openbmc/linux/drivers/dma/imx-dma.c (revision 4f3db074)
1 /*
2  * drivers/dma/imx-dma.c
3  *
4  * This file contains a driver for the Freescale i.MX DMA engine
5  * found on i.MX1/21/27
6  *
7  * Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
8  * Copyright 2012 Javier Martin, Vista Silicon <javier.martin@vista-silicon.com>
9  *
10  * The code contained herein is licensed under the GNU General Public
11  * License. You may obtain a copy of the GNU General Public License
12  * Version 2 or later at the following locations:
13  *
14  * http://www.opensource.org/licenses/gpl-license.html
15  * http://www.gnu.org/copyleft/gpl.html
16  */
17 #include <linux/err.h>
18 #include <linux/init.h>
19 #include <linux/types.h>
20 #include <linux/mm.h>
21 #include <linux/interrupt.h>
22 #include <linux/spinlock.h>
23 #include <linux/device.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/slab.h>
26 #include <linux/platform_device.h>
27 #include <linux/clk.h>
28 #include <linux/dmaengine.h>
29 #include <linux/module.h>
30 #include <linux/of_device.h>
31 #include <linux/of_dma.h>
32 
33 #include <asm/irq.h>
34 #include <linux/platform_data/dma-imx.h>
35 
36 #include "dmaengine.h"
37 #define IMXDMA_MAX_CHAN_DESCRIPTORS	16
38 #define IMX_DMA_CHANNELS  16
39 
40 #define IMX_DMA_2D_SLOTS	2
41 #define IMX_DMA_2D_SLOT_A	0
42 #define IMX_DMA_2D_SLOT_B	1
43 
44 #define IMX_DMA_LENGTH_LOOP	((unsigned int)-1)
45 #define IMX_DMA_MEMSIZE_32	(0 << 4)
46 #define IMX_DMA_MEMSIZE_8	(1 << 4)
47 #define IMX_DMA_MEMSIZE_16	(2 << 4)
48 #define IMX_DMA_TYPE_LINEAR	(0 << 10)
49 #define IMX_DMA_TYPE_2D		(1 << 10)
50 #define IMX_DMA_TYPE_FIFO	(2 << 10)
51 
52 #define IMX_DMA_ERR_BURST     (1 << 0)
53 #define IMX_DMA_ERR_REQUEST   (1 << 1)
54 #define IMX_DMA_ERR_TRANSFER  (1 << 2)
55 #define IMX_DMA_ERR_BUFFER    (1 << 3)
56 #define IMX_DMA_ERR_TIMEOUT   (1 << 4)
57 
58 #define DMA_DCR     0x00		/* Control Register */
59 #define DMA_DISR    0x04		/* Interrupt status Register */
60 #define DMA_DIMR    0x08		/* Interrupt mask Register */
61 #define DMA_DBTOSR  0x0c		/* Burst timeout status Register */
62 #define DMA_DRTOSR  0x10		/* Request timeout Register */
63 #define DMA_DSESR   0x14		/* Transfer Error Status Register */
64 #define DMA_DBOSR   0x18		/* Buffer overflow status Register */
65 #define DMA_DBTOCR  0x1c		/* Burst timeout control Register */
66 #define DMA_WSRA    0x40		/* W-Size Register A */
67 #define DMA_XSRA    0x44		/* X-Size Register A */
68 #define DMA_YSRA    0x48		/* Y-Size Register A */
69 #define DMA_WSRB    0x4c		/* W-Size Register B */
70 #define DMA_XSRB    0x50		/* X-Size Register B */
71 #define DMA_YSRB    0x54		/* Y-Size Register B */
72 #define DMA_SAR(x)  (0x80 + ((x) << 6))	/* Source Address Registers */
73 #define DMA_DAR(x)  (0x84 + ((x) << 6))	/* Destination Address Registers */
74 #define DMA_CNTR(x) (0x88 + ((x) << 6))	/* Count Registers */
75 #define DMA_CCR(x)  (0x8c + ((x) << 6))	/* Control Registers */
76 #define DMA_RSSR(x) (0x90 + ((x) << 6))	/* Request source select Registers */
77 #define DMA_BLR(x)  (0x94 + ((x) << 6))	/* Burst length Registers */
78 #define DMA_RTOR(x) (0x98 + ((x) << 6))	/* Request timeout Registers */
79 #define DMA_BUCR(x) (0x98 + ((x) << 6))	/* Bus Utilization Registers */
80 #define DMA_CCNR(x) (0x9C + ((x) << 6))	/* Channel counter Registers */
81 
82 #define DCR_DRST           (1<<1)
83 #define DCR_DEN            (1<<0)
84 #define DBTOCR_EN          (1<<15)
85 #define DBTOCR_CNT(x)      ((x) & 0x7fff)
86 #define CNTR_CNT(x)        ((x) & 0xffffff)
87 #define CCR_ACRPT          (1<<14)
88 #define CCR_DMOD_LINEAR    (0x0 << 12)
89 #define CCR_DMOD_2D        (0x1 << 12)
90 #define CCR_DMOD_FIFO      (0x2 << 12)
91 #define CCR_DMOD_EOBFIFO   (0x3 << 12)
92 #define CCR_SMOD_LINEAR    (0x0 << 10)
93 #define CCR_SMOD_2D        (0x1 << 10)
94 #define CCR_SMOD_FIFO      (0x2 << 10)
95 #define CCR_SMOD_EOBFIFO   (0x3 << 10)
96 #define CCR_MDIR_DEC       (1<<9)
97 #define CCR_MSEL_B         (1<<8)
98 #define CCR_DSIZ_32        (0x0 << 6)
99 #define CCR_DSIZ_8         (0x1 << 6)
100 #define CCR_DSIZ_16        (0x2 << 6)
101 #define CCR_SSIZ_32        (0x0 << 4)
102 #define CCR_SSIZ_8         (0x1 << 4)
103 #define CCR_SSIZ_16        (0x2 << 4)
104 #define CCR_REN            (1<<3)
105 #define CCR_RPT            (1<<2)
106 #define CCR_FRC            (1<<1)
107 #define CCR_CEN            (1<<0)
108 #define RTOR_EN            (1<<15)
109 #define RTOR_CLK           (1<<14)
110 #define RTOR_PSC           (1<<13)
111 
112 enum  imxdma_prep_type {
113 	IMXDMA_DESC_MEMCPY,
114 	IMXDMA_DESC_INTERLEAVED,
115 	IMXDMA_DESC_SLAVE_SG,
116 	IMXDMA_DESC_CYCLIC,
117 };
118 
119 struct imx_dma_2d_config {
120 	u16		xsr;
121 	u16		ysr;
122 	u16		wsr;
123 	int		count;
124 };
125 
126 struct imxdma_desc {
127 	struct list_head		node;
128 	struct dma_async_tx_descriptor	desc;
129 	enum dma_status			status;
130 	dma_addr_t			src;
131 	dma_addr_t			dest;
132 	size_t				len;
133 	enum dma_transfer_direction	direction;
134 	enum imxdma_prep_type		type;
135 	/* For memcpy and interleaved */
136 	unsigned int			config_port;
137 	unsigned int			config_mem;
138 	/* For interleaved transfers */
139 	unsigned int			x;
140 	unsigned int			y;
141 	unsigned int			w;
142 	/* For slave sg and cyclic */
143 	struct scatterlist		*sg;
144 	unsigned int			sgcount;
145 };
146 
147 struct imxdma_channel {
148 	int				hw_chaining;
149 	struct timer_list		watchdog;
150 	struct imxdma_engine		*imxdma;
151 	unsigned int			channel;
152 
153 	struct tasklet_struct		dma_tasklet;
154 	struct list_head		ld_free;
155 	struct list_head		ld_queue;
156 	struct list_head		ld_active;
157 	int				descs_allocated;
158 	enum dma_slave_buswidth		word_size;
159 	dma_addr_t			per_address;
160 	u32				watermark_level;
161 	struct dma_chan			chan;
162 	struct dma_async_tx_descriptor	desc;
163 	enum dma_status			status;
164 	int				dma_request;
165 	struct scatterlist		*sg_list;
166 	u32				ccr_from_device;
167 	u32				ccr_to_device;
168 	bool				enabled_2d;
169 	int				slot_2d;
170 };
171 
172 enum imx_dma_type {
173 	IMX1_DMA,
174 	IMX21_DMA,
175 	IMX27_DMA,
176 };
177 
178 struct imxdma_engine {
179 	struct device			*dev;
180 	struct device_dma_parameters	dma_parms;
181 	struct dma_device		dma_device;
182 	void __iomem			*base;
183 	struct clk			*dma_ahb;
184 	struct clk			*dma_ipg;
185 	spinlock_t			lock;
186 	struct imx_dma_2d_config	slots_2d[IMX_DMA_2D_SLOTS];
187 	struct imxdma_channel		channel[IMX_DMA_CHANNELS];
188 	enum imx_dma_type		devtype;
189 };
190 
191 struct imxdma_filter_data {
192 	struct imxdma_engine	*imxdma;
193 	int			 request;
194 };
195 
196 static struct platform_device_id imx_dma_devtype[] = {
197 	{
198 		.name = "imx1-dma",
199 		.driver_data = IMX1_DMA,
200 	}, {
201 		.name = "imx21-dma",
202 		.driver_data = IMX21_DMA,
203 	}, {
204 		.name = "imx27-dma",
205 		.driver_data = IMX27_DMA,
206 	}, {
207 		/* sentinel */
208 	}
209 };
210 MODULE_DEVICE_TABLE(platform, imx_dma_devtype);
211 
212 static const struct of_device_id imx_dma_of_dev_id[] = {
213 	{
214 		.compatible = "fsl,imx1-dma",
215 		.data = &imx_dma_devtype[IMX1_DMA],
216 	}, {
217 		.compatible = "fsl,imx21-dma",
218 		.data = &imx_dma_devtype[IMX21_DMA],
219 	}, {
220 		.compatible = "fsl,imx27-dma",
221 		.data = &imx_dma_devtype[IMX27_DMA],
222 	}, {
223 		/* sentinel */
224 	}
225 };
226 MODULE_DEVICE_TABLE(of, imx_dma_of_dev_id);
227 
228 static inline int is_imx1_dma(struct imxdma_engine *imxdma)
229 {
230 	return imxdma->devtype == IMX1_DMA;
231 }
232 
233 static inline int is_imx27_dma(struct imxdma_engine *imxdma)
234 {
235 	return imxdma->devtype == IMX27_DMA;
236 }
237 
238 static struct imxdma_channel *to_imxdma_chan(struct dma_chan *chan)
239 {
240 	return container_of(chan, struct imxdma_channel, chan);
241 }
242 
243 static inline bool imxdma_chan_is_doing_cyclic(struct imxdma_channel *imxdmac)
244 {
245 	struct imxdma_desc *desc;
246 
247 	if (!list_empty(&imxdmac->ld_active)) {
248 		desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc,
249 					node);
250 		if (desc->type == IMXDMA_DESC_CYCLIC)
251 			return true;
252 	}
253 	return false;
254 }
255 
256 
257 
258 static void imx_dmav1_writel(struct imxdma_engine *imxdma, unsigned val,
259 			     unsigned offset)
260 {
261 	__raw_writel(val, imxdma->base + offset);
262 }
263 
264 static unsigned imx_dmav1_readl(struct imxdma_engine *imxdma, unsigned offset)
265 {
266 	return __raw_readl(imxdma->base + offset);
267 }
268 
269 static int imxdma_hw_chain(struct imxdma_channel *imxdmac)
270 {
271 	struct imxdma_engine *imxdma = imxdmac->imxdma;
272 
273 	if (is_imx27_dma(imxdma))
274 		return imxdmac->hw_chaining;
275 	else
276 		return 0;
277 }
278 
279 /*
280  * imxdma_sg_next - prepare next chunk for scatter-gather DMA emulation
281  */
282 static inline int imxdma_sg_next(struct imxdma_desc *d)
283 {
284 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
285 	struct imxdma_engine *imxdma = imxdmac->imxdma;
286 	struct scatterlist *sg = d->sg;
287 	unsigned long now;
288 
289 	now = min(d->len, sg_dma_len(sg));
290 	if (d->len != IMX_DMA_LENGTH_LOOP)
291 		d->len -= now;
292 
293 	if (d->direction == DMA_DEV_TO_MEM)
294 		imx_dmav1_writel(imxdma, sg->dma_address,
295 				 DMA_DAR(imxdmac->channel));
296 	else
297 		imx_dmav1_writel(imxdma, sg->dma_address,
298 				 DMA_SAR(imxdmac->channel));
299 
300 	imx_dmav1_writel(imxdma, now, DMA_CNTR(imxdmac->channel));
301 
302 	dev_dbg(imxdma->dev, " %s channel: %d dst 0x%08x, src 0x%08x, "
303 		"size 0x%08x\n", __func__, imxdmac->channel,
304 		 imx_dmav1_readl(imxdma, DMA_DAR(imxdmac->channel)),
305 		 imx_dmav1_readl(imxdma, DMA_SAR(imxdmac->channel)),
306 		 imx_dmav1_readl(imxdma, DMA_CNTR(imxdmac->channel)));
307 
308 	return now;
309 }
310 
311 static void imxdma_enable_hw(struct imxdma_desc *d)
312 {
313 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
314 	struct imxdma_engine *imxdma = imxdmac->imxdma;
315 	int channel = imxdmac->channel;
316 	unsigned long flags;
317 
318 	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
319 
320 	local_irq_save(flags);
321 
322 	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
323 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) &
324 			 ~(1 << channel), DMA_DIMR);
325 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) |
326 			 CCR_CEN | CCR_ACRPT, DMA_CCR(channel));
327 
328 	if (!is_imx1_dma(imxdma) &&
329 			d->sg && imxdma_hw_chain(imxdmac)) {
330 		d->sg = sg_next(d->sg);
331 		if (d->sg) {
332 			u32 tmp;
333 			imxdma_sg_next(d);
334 			tmp = imx_dmav1_readl(imxdma, DMA_CCR(channel));
335 			imx_dmav1_writel(imxdma, tmp | CCR_RPT | CCR_ACRPT,
336 					 DMA_CCR(channel));
337 		}
338 	}
339 
340 	local_irq_restore(flags);
341 }
342 
343 static void imxdma_disable_hw(struct imxdma_channel *imxdmac)
344 {
345 	struct imxdma_engine *imxdma = imxdmac->imxdma;
346 	int channel = imxdmac->channel;
347 	unsigned long flags;
348 
349 	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
350 
351 	if (imxdma_hw_chain(imxdmac))
352 		del_timer(&imxdmac->watchdog);
353 
354 	local_irq_save(flags);
355 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) |
356 			 (1 << channel), DMA_DIMR);
357 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) &
358 			 ~CCR_CEN, DMA_CCR(channel));
359 	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
360 	local_irq_restore(flags);
361 }
362 
363 static void imxdma_watchdog(unsigned long data)
364 {
365 	struct imxdma_channel *imxdmac = (struct imxdma_channel *)data;
366 	struct imxdma_engine *imxdma = imxdmac->imxdma;
367 	int channel = imxdmac->channel;
368 
369 	imx_dmav1_writel(imxdma, 0, DMA_CCR(channel));
370 
371 	/* Tasklet watchdog error handler */
372 	tasklet_schedule(&imxdmac->dma_tasklet);
373 	dev_dbg(imxdma->dev, "channel %d: watchdog timeout!\n",
374 		imxdmac->channel);
375 }
376 
377 static irqreturn_t imxdma_err_handler(int irq, void *dev_id)
378 {
379 	struct imxdma_engine *imxdma = dev_id;
380 	unsigned int err_mask;
381 	int i, disr;
382 	int errcode;
383 
384 	disr = imx_dmav1_readl(imxdma, DMA_DISR);
385 
386 	err_mask = imx_dmav1_readl(imxdma, DMA_DBTOSR) |
387 		   imx_dmav1_readl(imxdma, DMA_DRTOSR) |
388 		   imx_dmav1_readl(imxdma, DMA_DSESR)  |
389 		   imx_dmav1_readl(imxdma, DMA_DBOSR);
390 
391 	if (!err_mask)
392 		return IRQ_HANDLED;
393 
394 	imx_dmav1_writel(imxdma, disr & err_mask, DMA_DISR);
395 
396 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
397 		if (!(err_mask & (1 << i)))
398 			continue;
399 		errcode = 0;
400 
401 		if (imx_dmav1_readl(imxdma, DMA_DBTOSR) & (1 << i)) {
402 			imx_dmav1_writel(imxdma, 1 << i, DMA_DBTOSR);
403 			errcode |= IMX_DMA_ERR_BURST;
404 		}
405 		if (imx_dmav1_readl(imxdma, DMA_DRTOSR) & (1 << i)) {
406 			imx_dmav1_writel(imxdma, 1 << i, DMA_DRTOSR);
407 			errcode |= IMX_DMA_ERR_REQUEST;
408 		}
409 		if (imx_dmav1_readl(imxdma, DMA_DSESR) & (1 << i)) {
410 			imx_dmav1_writel(imxdma, 1 << i, DMA_DSESR);
411 			errcode |= IMX_DMA_ERR_TRANSFER;
412 		}
413 		if (imx_dmav1_readl(imxdma, DMA_DBOSR) & (1 << i)) {
414 			imx_dmav1_writel(imxdma, 1 << i, DMA_DBOSR);
415 			errcode |= IMX_DMA_ERR_BUFFER;
416 		}
417 		/* Tasklet error handler */
418 		tasklet_schedule(&imxdma->channel[i].dma_tasklet);
419 
420 		dev_warn(imxdma->dev,
421 			 "DMA timeout on channel %d -%s%s%s%s\n", i,
422 			 errcode & IMX_DMA_ERR_BURST ?    " burst" : "",
423 			 errcode & IMX_DMA_ERR_REQUEST ?  " request" : "",
424 			 errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "",
425 			 errcode & IMX_DMA_ERR_BUFFER ?   " buffer" : "");
426 	}
427 	return IRQ_HANDLED;
428 }
429 
430 static void dma_irq_handle_channel(struct imxdma_channel *imxdmac)
431 {
432 	struct imxdma_engine *imxdma = imxdmac->imxdma;
433 	int chno = imxdmac->channel;
434 	struct imxdma_desc *desc;
435 	unsigned long flags;
436 
437 	spin_lock_irqsave(&imxdma->lock, flags);
438 	if (list_empty(&imxdmac->ld_active)) {
439 		spin_unlock_irqrestore(&imxdma->lock, flags);
440 		goto out;
441 	}
442 
443 	desc = list_first_entry(&imxdmac->ld_active,
444 				struct imxdma_desc,
445 				node);
446 	spin_unlock_irqrestore(&imxdma->lock, flags);
447 
448 	if (desc->sg) {
449 		u32 tmp;
450 		desc->sg = sg_next(desc->sg);
451 
452 		if (desc->sg) {
453 			imxdma_sg_next(desc);
454 
455 			tmp = imx_dmav1_readl(imxdma, DMA_CCR(chno));
456 
457 			if (imxdma_hw_chain(imxdmac)) {
458 				/* FIXME: The timeout should probably be
459 				 * configurable
460 				 */
461 				mod_timer(&imxdmac->watchdog,
462 					jiffies + msecs_to_jiffies(500));
463 
464 				tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT;
465 				imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
466 			} else {
467 				imx_dmav1_writel(imxdma, tmp & ~CCR_CEN,
468 						 DMA_CCR(chno));
469 				tmp |= CCR_CEN;
470 			}
471 
472 			imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
473 
474 			if (imxdma_chan_is_doing_cyclic(imxdmac))
475 				/* Tasklet progression */
476 				tasklet_schedule(&imxdmac->dma_tasklet);
477 
478 			return;
479 		}
480 
481 		if (imxdma_hw_chain(imxdmac)) {
482 			del_timer(&imxdmac->watchdog);
483 			return;
484 		}
485 	}
486 
487 out:
488 	imx_dmav1_writel(imxdma, 0, DMA_CCR(chno));
489 	/* Tasklet irq */
490 	tasklet_schedule(&imxdmac->dma_tasklet);
491 }
492 
493 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
494 {
495 	struct imxdma_engine *imxdma = dev_id;
496 	int i, disr;
497 
498 	if (!is_imx1_dma(imxdma))
499 		imxdma_err_handler(irq, dev_id);
500 
501 	disr = imx_dmav1_readl(imxdma, DMA_DISR);
502 
503 	dev_dbg(imxdma->dev, "%s called, disr=0x%08x\n", __func__, disr);
504 
505 	imx_dmav1_writel(imxdma, disr, DMA_DISR);
506 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
507 		if (disr & (1 << i))
508 			dma_irq_handle_channel(&imxdma->channel[i]);
509 	}
510 
511 	return IRQ_HANDLED;
512 }
513 
514 static int imxdma_xfer_desc(struct imxdma_desc *d)
515 {
516 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
517 	struct imxdma_engine *imxdma = imxdmac->imxdma;
518 	int slot = -1;
519 	int i;
520 
521 	/* Configure and enable */
522 	switch (d->type) {
523 	case IMXDMA_DESC_INTERLEAVED:
524 		/* Try to get a free 2D slot */
525 		for (i = 0; i < IMX_DMA_2D_SLOTS; i++) {
526 			if ((imxdma->slots_2d[i].count > 0) &&
527 			((imxdma->slots_2d[i].xsr != d->x) ||
528 			(imxdma->slots_2d[i].ysr != d->y) ||
529 			(imxdma->slots_2d[i].wsr != d->w)))
530 				continue;
531 			slot = i;
532 			break;
533 		}
534 		if (slot < 0)
535 			return -EBUSY;
536 
537 		imxdma->slots_2d[slot].xsr = d->x;
538 		imxdma->slots_2d[slot].ysr = d->y;
539 		imxdma->slots_2d[slot].wsr = d->w;
540 		imxdma->slots_2d[slot].count++;
541 
542 		imxdmac->slot_2d = slot;
543 		imxdmac->enabled_2d = true;
544 
545 		if (slot == IMX_DMA_2D_SLOT_A) {
546 			d->config_mem &= ~CCR_MSEL_B;
547 			d->config_port &= ~CCR_MSEL_B;
548 			imx_dmav1_writel(imxdma, d->x, DMA_XSRA);
549 			imx_dmav1_writel(imxdma, d->y, DMA_YSRA);
550 			imx_dmav1_writel(imxdma, d->w, DMA_WSRA);
551 		} else {
552 			d->config_mem |= CCR_MSEL_B;
553 			d->config_port |= CCR_MSEL_B;
554 			imx_dmav1_writel(imxdma, d->x, DMA_XSRB);
555 			imx_dmav1_writel(imxdma, d->y, DMA_YSRB);
556 			imx_dmav1_writel(imxdma, d->w, DMA_WSRB);
557 		}
558 		/*
559 		 * We fall-through here intentionally, since a 2D transfer is
560 		 * similar to MEMCPY just adding the 2D slot configuration.
561 		 */
562 	case IMXDMA_DESC_MEMCPY:
563 		imx_dmav1_writel(imxdma, d->src, DMA_SAR(imxdmac->channel));
564 		imx_dmav1_writel(imxdma, d->dest, DMA_DAR(imxdmac->channel));
565 		imx_dmav1_writel(imxdma, d->config_mem | (d->config_port << 2),
566 			 DMA_CCR(imxdmac->channel));
567 
568 		imx_dmav1_writel(imxdma, d->len, DMA_CNTR(imxdmac->channel));
569 
570 		dev_dbg(imxdma->dev,
571 			"%s channel: %d dest=0x%08llx src=0x%08llx dma_length=%zu\n",
572 			__func__, imxdmac->channel,
573 			(unsigned long long)d->dest,
574 			(unsigned long long)d->src, d->len);
575 
576 		break;
577 	/* Cyclic transfer is the same as slave_sg with special sg configuration. */
578 	case IMXDMA_DESC_CYCLIC:
579 	case IMXDMA_DESC_SLAVE_SG:
580 		if (d->direction == DMA_DEV_TO_MEM) {
581 			imx_dmav1_writel(imxdma, imxdmac->per_address,
582 					 DMA_SAR(imxdmac->channel));
583 			imx_dmav1_writel(imxdma, imxdmac->ccr_from_device,
584 					 DMA_CCR(imxdmac->channel));
585 
586 			dev_dbg(imxdma->dev,
587 				"%s channel: %d sg=%p sgcount=%d total length=%zu dev_addr=0x%08llx (dev2mem)\n",
588 				__func__, imxdmac->channel,
589 				d->sg, d->sgcount, d->len,
590 				(unsigned long long)imxdmac->per_address);
591 		} else if (d->direction == DMA_MEM_TO_DEV) {
592 			imx_dmav1_writel(imxdma, imxdmac->per_address,
593 					 DMA_DAR(imxdmac->channel));
594 			imx_dmav1_writel(imxdma, imxdmac->ccr_to_device,
595 					 DMA_CCR(imxdmac->channel));
596 
597 			dev_dbg(imxdma->dev,
598 				"%s channel: %d sg=%p sgcount=%d total length=%zu dev_addr=0x%08llx (mem2dev)\n",
599 				__func__, imxdmac->channel,
600 				d->sg, d->sgcount, d->len,
601 				(unsigned long long)imxdmac->per_address);
602 		} else {
603 			dev_err(imxdma->dev, "%s channel: %d bad dma mode\n",
604 				__func__, imxdmac->channel);
605 			return -EINVAL;
606 		}
607 
608 		imxdma_sg_next(d);
609 
610 		break;
611 	default:
612 		return -EINVAL;
613 	}
614 	imxdma_enable_hw(d);
615 	return 0;
616 }
617 
618 static void imxdma_tasklet(unsigned long data)
619 {
620 	struct imxdma_channel *imxdmac = (void *)data;
621 	struct imxdma_engine *imxdma = imxdmac->imxdma;
622 	struct imxdma_desc *desc;
623 	unsigned long flags;
624 
625 	spin_lock_irqsave(&imxdma->lock, flags);
626 
627 	if (list_empty(&imxdmac->ld_active)) {
628 		/* Someone might have called terminate all */
629 		spin_unlock_irqrestore(&imxdma->lock, flags);
630 		return;
631 	}
632 	desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc, node);
633 
634 	/* If we are dealing with a cyclic descriptor, keep it on ld_active
635 	 * and dont mark the descriptor as complete.
636 	 * Only in non-cyclic cases it would be marked as complete
637 	 */
638 	if (imxdma_chan_is_doing_cyclic(imxdmac))
639 		goto out;
640 	else
641 		dma_cookie_complete(&desc->desc);
642 
643 	/* Free 2D slot if it was an interleaved transfer */
644 	if (imxdmac->enabled_2d) {
645 		imxdma->slots_2d[imxdmac->slot_2d].count--;
646 		imxdmac->enabled_2d = false;
647 	}
648 
649 	list_move_tail(imxdmac->ld_active.next, &imxdmac->ld_free);
650 
651 	if (!list_empty(&imxdmac->ld_queue)) {
652 		desc = list_first_entry(&imxdmac->ld_queue, struct imxdma_desc,
653 					node);
654 		list_move_tail(imxdmac->ld_queue.next, &imxdmac->ld_active);
655 		if (imxdma_xfer_desc(desc) < 0)
656 			dev_warn(imxdma->dev, "%s: channel: %d couldn't xfer desc\n",
657 				 __func__, imxdmac->channel);
658 	}
659 out:
660 	spin_unlock_irqrestore(&imxdma->lock, flags);
661 
662 	if (desc->desc.callback)
663 		desc->desc.callback(desc->desc.callback_param);
664 
665 }
666 
667 static int imxdma_terminate_all(struct dma_chan *chan)
668 {
669 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
670 	struct imxdma_engine *imxdma = imxdmac->imxdma;
671 	unsigned long flags;
672 
673 	imxdma_disable_hw(imxdmac);
674 
675 	spin_lock_irqsave(&imxdma->lock, flags);
676 	list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
677 	list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
678 	spin_unlock_irqrestore(&imxdma->lock, flags);
679 	return 0;
680 }
681 
682 static int imxdma_config(struct dma_chan *chan,
683 			 struct dma_slave_config *dmaengine_cfg)
684 {
685 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
686 	struct imxdma_engine *imxdma = imxdmac->imxdma;
687 	unsigned int mode = 0;
688 
689 	if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
690 		imxdmac->per_address = dmaengine_cfg->src_addr;
691 		imxdmac->watermark_level = dmaengine_cfg->src_maxburst;
692 		imxdmac->word_size = dmaengine_cfg->src_addr_width;
693 	} else {
694 		imxdmac->per_address = dmaengine_cfg->dst_addr;
695 		imxdmac->watermark_level = dmaengine_cfg->dst_maxburst;
696 		imxdmac->word_size = dmaengine_cfg->dst_addr_width;
697 	}
698 
699 	switch (imxdmac->word_size) {
700 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
701 		mode = IMX_DMA_MEMSIZE_8;
702 		break;
703 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
704 		mode = IMX_DMA_MEMSIZE_16;
705 		break;
706 	default:
707 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
708 		mode = IMX_DMA_MEMSIZE_32;
709 		break;
710 	}
711 
712 	imxdmac->hw_chaining = 0;
713 
714 	imxdmac->ccr_from_device = (mode | IMX_DMA_TYPE_FIFO) |
715 		((IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) << 2) |
716 		CCR_REN;
717 	imxdmac->ccr_to_device =
718 		(IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) |
719 		((mode | IMX_DMA_TYPE_FIFO) << 2) | CCR_REN;
720 	imx_dmav1_writel(imxdma, imxdmac->dma_request,
721 			 DMA_RSSR(imxdmac->channel));
722 
723 	/* Set burst length */
724 	imx_dmav1_writel(imxdma, imxdmac->watermark_level *
725 			 imxdmac->word_size, DMA_BLR(imxdmac->channel));
726 
727 	return 0;
728 }
729 
730 static enum dma_status imxdma_tx_status(struct dma_chan *chan,
731 					    dma_cookie_t cookie,
732 					    struct dma_tx_state *txstate)
733 {
734 	return dma_cookie_status(chan, cookie, txstate);
735 }
736 
737 static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
738 {
739 	struct imxdma_channel *imxdmac = to_imxdma_chan(tx->chan);
740 	struct imxdma_engine *imxdma = imxdmac->imxdma;
741 	dma_cookie_t cookie;
742 	unsigned long flags;
743 
744 	spin_lock_irqsave(&imxdma->lock, flags);
745 	list_move_tail(imxdmac->ld_free.next, &imxdmac->ld_queue);
746 	cookie = dma_cookie_assign(tx);
747 	spin_unlock_irqrestore(&imxdma->lock, flags);
748 
749 	return cookie;
750 }
751 
752 static int imxdma_alloc_chan_resources(struct dma_chan *chan)
753 {
754 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
755 	struct imx_dma_data *data = chan->private;
756 
757 	if (data != NULL)
758 		imxdmac->dma_request = data->dma_request;
759 
760 	while (imxdmac->descs_allocated < IMXDMA_MAX_CHAN_DESCRIPTORS) {
761 		struct imxdma_desc *desc;
762 
763 		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
764 		if (!desc)
765 			break;
766 		__memzero(&desc->desc, sizeof(struct dma_async_tx_descriptor));
767 		dma_async_tx_descriptor_init(&desc->desc, chan);
768 		desc->desc.tx_submit = imxdma_tx_submit;
769 		/* txd.flags will be overwritten in prep funcs */
770 		desc->desc.flags = DMA_CTRL_ACK;
771 		desc->status = DMA_COMPLETE;
772 
773 		list_add_tail(&desc->node, &imxdmac->ld_free);
774 		imxdmac->descs_allocated++;
775 	}
776 
777 	if (!imxdmac->descs_allocated)
778 		return -ENOMEM;
779 
780 	return imxdmac->descs_allocated;
781 }
782 
783 static void imxdma_free_chan_resources(struct dma_chan *chan)
784 {
785 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
786 	struct imxdma_engine *imxdma = imxdmac->imxdma;
787 	struct imxdma_desc *desc, *_desc;
788 	unsigned long flags;
789 
790 	spin_lock_irqsave(&imxdma->lock, flags);
791 
792 	imxdma_disable_hw(imxdmac);
793 	list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
794 	list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
795 
796 	spin_unlock_irqrestore(&imxdma->lock, flags);
797 
798 	list_for_each_entry_safe(desc, _desc, &imxdmac->ld_free, node) {
799 		kfree(desc);
800 		imxdmac->descs_allocated--;
801 	}
802 	INIT_LIST_HEAD(&imxdmac->ld_free);
803 
804 	kfree(imxdmac->sg_list);
805 	imxdmac->sg_list = NULL;
806 }
807 
808 static struct dma_async_tx_descriptor *imxdma_prep_slave_sg(
809 		struct dma_chan *chan, struct scatterlist *sgl,
810 		unsigned int sg_len, enum dma_transfer_direction direction,
811 		unsigned long flags, void *context)
812 {
813 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
814 	struct scatterlist *sg;
815 	int i, dma_length = 0;
816 	struct imxdma_desc *desc;
817 
818 	if (list_empty(&imxdmac->ld_free) ||
819 	    imxdma_chan_is_doing_cyclic(imxdmac))
820 		return NULL;
821 
822 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
823 
824 	for_each_sg(sgl, sg, sg_len, i) {
825 		dma_length += sg_dma_len(sg);
826 	}
827 
828 	switch (imxdmac->word_size) {
829 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
830 		if (sg_dma_len(sgl) & 3 || sgl->dma_address & 3)
831 			return NULL;
832 		break;
833 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
834 		if (sg_dma_len(sgl) & 1 || sgl->dma_address & 1)
835 			return NULL;
836 		break;
837 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
838 		break;
839 	default:
840 		return NULL;
841 	}
842 
843 	desc->type = IMXDMA_DESC_SLAVE_SG;
844 	desc->sg = sgl;
845 	desc->sgcount = sg_len;
846 	desc->len = dma_length;
847 	desc->direction = direction;
848 	if (direction == DMA_DEV_TO_MEM) {
849 		desc->src = imxdmac->per_address;
850 	} else {
851 		desc->dest = imxdmac->per_address;
852 	}
853 	desc->desc.callback = NULL;
854 	desc->desc.callback_param = NULL;
855 
856 	return &desc->desc;
857 }
858 
859 static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
860 		struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
861 		size_t period_len, enum dma_transfer_direction direction,
862 		unsigned long flags)
863 {
864 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
865 	struct imxdma_engine *imxdma = imxdmac->imxdma;
866 	struct imxdma_desc *desc;
867 	int i;
868 	unsigned int periods = buf_len / period_len;
869 
870 	dev_dbg(imxdma->dev, "%s channel: %d buf_len=%zu period_len=%zu\n",
871 			__func__, imxdmac->channel, buf_len, period_len);
872 
873 	if (list_empty(&imxdmac->ld_free) ||
874 	    imxdma_chan_is_doing_cyclic(imxdmac))
875 		return NULL;
876 
877 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
878 
879 	kfree(imxdmac->sg_list);
880 
881 	imxdmac->sg_list = kcalloc(periods + 1,
882 			sizeof(struct scatterlist), GFP_ATOMIC);
883 	if (!imxdmac->sg_list)
884 		return NULL;
885 
886 	sg_init_table(imxdmac->sg_list, periods);
887 
888 	for (i = 0; i < periods; i++) {
889 		imxdmac->sg_list[i].page_link = 0;
890 		imxdmac->sg_list[i].offset = 0;
891 		imxdmac->sg_list[i].dma_address = dma_addr;
892 		sg_dma_len(&imxdmac->sg_list[i]) = period_len;
893 		dma_addr += period_len;
894 	}
895 
896 	/* close the loop */
897 	imxdmac->sg_list[periods].offset = 0;
898 	sg_dma_len(&imxdmac->sg_list[periods]) = 0;
899 	imxdmac->sg_list[periods].page_link =
900 		((unsigned long)imxdmac->sg_list | 0x01) & ~0x02;
901 
902 	desc->type = IMXDMA_DESC_CYCLIC;
903 	desc->sg = imxdmac->sg_list;
904 	desc->sgcount = periods;
905 	desc->len = IMX_DMA_LENGTH_LOOP;
906 	desc->direction = direction;
907 	if (direction == DMA_DEV_TO_MEM) {
908 		desc->src = imxdmac->per_address;
909 	} else {
910 		desc->dest = imxdmac->per_address;
911 	}
912 	desc->desc.callback = NULL;
913 	desc->desc.callback_param = NULL;
914 
915 	return &desc->desc;
916 }
917 
918 static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
919 	struct dma_chan *chan, dma_addr_t dest,
920 	dma_addr_t src, size_t len, unsigned long flags)
921 {
922 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
923 	struct imxdma_engine *imxdma = imxdmac->imxdma;
924 	struct imxdma_desc *desc;
925 
926 	dev_dbg(imxdma->dev, "%s channel: %d src=0x%llx dst=0x%llx len=%zu\n",
927 		__func__, imxdmac->channel, (unsigned long long)src,
928 		(unsigned long long)dest, len);
929 
930 	if (list_empty(&imxdmac->ld_free) ||
931 	    imxdma_chan_is_doing_cyclic(imxdmac))
932 		return NULL;
933 
934 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
935 
936 	desc->type = IMXDMA_DESC_MEMCPY;
937 	desc->src = src;
938 	desc->dest = dest;
939 	desc->len = len;
940 	desc->direction = DMA_MEM_TO_MEM;
941 	desc->config_port = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
942 	desc->config_mem = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
943 	desc->desc.callback = NULL;
944 	desc->desc.callback_param = NULL;
945 
946 	return &desc->desc;
947 }
948 
949 static struct dma_async_tx_descriptor *imxdma_prep_dma_interleaved(
950 	struct dma_chan *chan, struct dma_interleaved_template *xt,
951 	unsigned long flags)
952 {
953 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
954 	struct imxdma_engine *imxdma = imxdmac->imxdma;
955 	struct imxdma_desc *desc;
956 
957 	dev_dbg(imxdma->dev, "%s channel: %d src_start=0x%llx dst_start=0x%llx\n"
958 		"   src_sgl=%s dst_sgl=%s numf=%zu frame_size=%zu\n", __func__,
959 		imxdmac->channel, (unsigned long long)xt->src_start,
960 		(unsigned long long) xt->dst_start,
961 		xt->src_sgl ? "true" : "false", xt->dst_sgl ? "true" : "false",
962 		xt->numf, xt->frame_size);
963 
964 	if (list_empty(&imxdmac->ld_free) ||
965 	    imxdma_chan_is_doing_cyclic(imxdmac))
966 		return NULL;
967 
968 	if (xt->frame_size != 1 || xt->numf <= 0 || xt->dir != DMA_MEM_TO_MEM)
969 		return NULL;
970 
971 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
972 
973 	desc->type = IMXDMA_DESC_INTERLEAVED;
974 	desc->src = xt->src_start;
975 	desc->dest = xt->dst_start;
976 	desc->x = xt->sgl[0].size;
977 	desc->y = xt->numf;
978 	desc->w = xt->sgl[0].icg + desc->x;
979 	desc->len = desc->x * desc->y;
980 	desc->direction = DMA_MEM_TO_MEM;
981 	desc->config_port = IMX_DMA_MEMSIZE_32;
982 	desc->config_mem = IMX_DMA_MEMSIZE_32;
983 	if (xt->src_sgl)
984 		desc->config_mem |= IMX_DMA_TYPE_2D;
985 	if (xt->dst_sgl)
986 		desc->config_port |= IMX_DMA_TYPE_2D;
987 	desc->desc.callback = NULL;
988 	desc->desc.callback_param = NULL;
989 
990 	return &desc->desc;
991 }
992 
993 static void imxdma_issue_pending(struct dma_chan *chan)
994 {
995 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
996 	struct imxdma_engine *imxdma = imxdmac->imxdma;
997 	struct imxdma_desc *desc;
998 	unsigned long flags;
999 
1000 	spin_lock_irqsave(&imxdma->lock, flags);
1001 	if (list_empty(&imxdmac->ld_active) &&
1002 	    !list_empty(&imxdmac->ld_queue)) {
1003 		desc = list_first_entry(&imxdmac->ld_queue,
1004 					struct imxdma_desc, node);
1005 
1006 		if (imxdma_xfer_desc(desc) < 0) {
1007 			dev_warn(imxdma->dev,
1008 				 "%s: channel: %d couldn't issue DMA xfer\n",
1009 				 __func__, imxdmac->channel);
1010 		} else {
1011 			list_move_tail(imxdmac->ld_queue.next,
1012 				       &imxdmac->ld_active);
1013 		}
1014 	}
1015 	spin_unlock_irqrestore(&imxdma->lock, flags);
1016 }
1017 
1018 static bool imxdma_filter_fn(struct dma_chan *chan, void *param)
1019 {
1020 	struct imxdma_filter_data *fdata = param;
1021 	struct imxdma_channel *imxdma_chan = to_imxdma_chan(chan);
1022 
1023 	if (chan->device->dev != fdata->imxdma->dev)
1024 		return false;
1025 
1026 	imxdma_chan->dma_request = fdata->request;
1027 	chan->private = NULL;
1028 
1029 	return true;
1030 }
1031 
1032 static struct dma_chan *imxdma_xlate(struct of_phandle_args *dma_spec,
1033 						struct of_dma *ofdma)
1034 {
1035 	int count = dma_spec->args_count;
1036 	struct imxdma_engine *imxdma = ofdma->of_dma_data;
1037 	struct imxdma_filter_data fdata = {
1038 		.imxdma = imxdma,
1039 	};
1040 
1041 	if (count != 1)
1042 		return NULL;
1043 
1044 	fdata.request = dma_spec->args[0];
1045 
1046 	return dma_request_channel(imxdma->dma_device.cap_mask,
1047 					imxdma_filter_fn, &fdata);
1048 }
1049 
1050 static int __init imxdma_probe(struct platform_device *pdev)
1051 	{
1052 	struct imxdma_engine *imxdma;
1053 	struct resource *res;
1054 	const struct of_device_id *of_id;
1055 	int ret, i;
1056 	int irq, irq_err;
1057 
1058 	of_id = of_match_device(imx_dma_of_dev_id, &pdev->dev);
1059 	if (of_id)
1060 		pdev->id_entry = of_id->data;
1061 
1062 	imxdma = devm_kzalloc(&pdev->dev, sizeof(*imxdma), GFP_KERNEL);
1063 	if (!imxdma)
1064 		return -ENOMEM;
1065 
1066 	imxdma->dev = &pdev->dev;
1067 	imxdma->devtype = pdev->id_entry->driver_data;
1068 
1069 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1070 	imxdma->base = devm_ioremap_resource(&pdev->dev, res);
1071 	if (IS_ERR(imxdma->base))
1072 		return PTR_ERR(imxdma->base);
1073 
1074 	irq = platform_get_irq(pdev, 0);
1075 	if (irq < 0)
1076 		return irq;
1077 
1078 	imxdma->dma_ipg = devm_clk_get(&pdev->dev, "ipg");
1079 	if (IS_ERR(imxdma->dma_ipg))
1080 		return PTR_ERR(imxdma->dma_ipg);
1081 
1082 	imxdma->dma_ahb = devm_clk_get(&pdev->dev, "ahb");
1083 	if (IS_ERR(imxdma->dma_ahb))
1084 		return PTR_ERR(imxdma->dma_ahb);
1085 
1086 	clk_prepare_enable(imxdma->dma_ipg);
1087 	clk_prepare_enable(imxdma->dma_ahb);
1088 
1089 	/* reset DMA module */
1090 	imx_dmav1_writel(imxdma, DCR_DRST, DMA_DCR);
1091 
1092 	if (is_imx1_dma(imxdma)) {
1093 		ret = devm_request_irq(&pdev->dev, irq,
1094 				       dma_irq_handler, 0, "DMA", imxdma);
1095 		if (ret) {
1096 			dev_warn(imxdma->dev, "Can't register IRQ for DMA\n");
1097 			goto err;
1098 		}
1099 
1100 		irq_err = platform_get_irq(pdev, 1);
1101 		if (irq_err < 0) {
1102 			ret = irq_err;
1103 			goto err;
1104 		}
1105 
1106 		ret = devm_request_irq(&pdev->dev, irq_err,
1107 				       imxdma_err_handler, 0, "DMA", imxdma);
1108 		if (ret) {
1109 			dev_warn(imxdma->dev, "Can't register ERRIRQ for DMA\n");
1110 			goto err;
1111 		}
1112 	}
1113 
1114 	/* enable DMA module */
1115 	imx_dmav1_writel(imxdma, DCR_DEN, DMA_DCR);
1116 
1117 	/* clear all interrupts */
1118 	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DISR);
1119 
1120 	/* disable interrupts */
1121 	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR);
1122 
1123 	INIT_LIST_HEAD(&imxdma->dma_device.channels);
1124 
1125 	dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
1126 	dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
1127 	dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
1128 	dma_cap_set(DMA_INTERLEAVE, imxdma->dma_device.cap_mask);
1129 
1130 	/* Initialize 2D global parameters */
1131 	for (i = 0; i < IMX_DMA_2D_SLOTS; i++)
1132 		imxdma->slots_2d[i].count = 0;
1133 
1134 	spin_lock_init(&imxdma->lock);
1135 
1136 	/* Initialize channel parameters */
1137 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
1138 		struct imxdma_channel *imxdmac = &imxdma->channel[i];
1139 
1140 		if (!is_imx1_dma(imxdma)) {
1141 			ret = devm_request_irq(&pdev->dev, irq + i,
1142 					dma_irq_handler, 0, "DMA", imxdma);
1143 			if (ret) {
1144 				dev_warn(imxdma->dev, "Can't register IRQ %d "
1145 					 "for DMA channel %d\n",
1146 					 irq + i, i);
1147 				goto err;
1148 			}
1149 			init_timer(&imxdmac->watchdog);
1150 			imxdmac->watchdog.function = &imxdma_watchdog;
1151 			imxdmac->watchdog.data = (unsigned long)imxdmac;
1152 		}
1153 
1154 		imxdmac->imxdma = imxdma;
1155 
1156 		INIT_LIST_HEAD(&imxdmac->ld_queue);
1157 		INIT_LIST_HEAD(&imxdmac->ld_free);
1158 		INIT_LIST_HEAD(&imxdmac->ld_active);
1159 
1160 		tasklet_init(&imxdmac->dma_tasklet, imxdma_tasklet,
1161 			     (unsigned long)imxdmac);
1162 		imxdmac->chan.device = &imxdma->dma_device;
1163 		dma_cookie_init(&imxdmac->chan);
1164 		imxdmac->channel = i;
1165 
1166 		/* Add the channel to the DMAC list */
1167 		list_add_tail(&imxdmac->chan.device_node,
1168 			      &imxdma->dma_device.channels);
1169 	}
1170 
1171 	imxdma->dma_device.dev = &pdev->dev;
1172 
1173 	imxdma->dma_device.device_alloc_chan_resources = imxdma_alloc_chan_resources;
1174 	imxdma->dma_device.device_free_chan_resources = imxdma_free_chan_resources;
1175 	imxdma->dma_device.device_tx_status = imxdma_tx_status;
1176 	imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
1177 	imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
1178 	imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
1179 	imxdma->dma_device.device_prep_interleaved_dma = imxdma_prep_dma_interleaved;
1180 	imxdma->dma_device.device_config = imxdma_config;
1181 	imxdma->dma_device.device_terminate_all = imxdma_terminate_all;
1182 	imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
1183 
1184 	platform_set_drvdata(pdev, imxdma);
1185 
1186 	imxdma->dma_device.copy_align = 2; /* 2^2 = 4 bytes alignment */
1187 	imxdma->dma_device.dev->dma_parms = &imxdma->dma_parms;
1188 	dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);
1189 
1190 	ret = dma_async_device_register(&imxdma->dma_device);
1191 	if (ret) {
1192 		dev_err(&pdev->dev, "unable to register\n");
1193 		goto err;
1194 	}
1195 
1196 	if (pdev->dev.of_node) {
1197 		ret = of_dma_controller_register(pdev->dev.of_node,
1198 				imxdma_xlate, imxdma);
1199 		if (ret) {
1200 			dev_err(&pdev->dev, "unable to register of_dma_controller\n");
1201 			goto err_of_dma_controller;
1202 		}
1203 	}
1204 
1205 	return 0;
1206 
1207 err_of_dma_controller:
1208 	dma_async_device_unregister(&imxdma->dma_device);
1209 err:
1210 	clk_disable_unprepare(imxdma->dma_ipg);
1211 	clk_disable_unprepare(imxdma->dma_ahb);
1212 	return ret;
1213 }
1214 
1215 static int imxdma_remove(struct platform_device *pdev)
1216 {
1217 	struct imxdma_engine *imxdma = platform_get_drvdata(pdev);
1218 
1219         dma_async_device_unregister(&imxdma->dma_device);
1220 
1221 	if (pdev->dev.of_node)
1222 		of_dma_controller_free(pdev->dev.of_node);
1223 
1224 	clk_disable_unprepare(imxdma->dma_ipg);
1225 	clk_disable_unprepare(imxdma->dma_ahb);
1226 
1227         return 0;
1228 }
1229 
1230 static struct platform_driver imxdma_driver = {
1231 	.driver		= {
1232 		.name	= "imx-dma",
1233 		.of_match_table = imx_dma_of_dev_id,
1234 	},
1235 	.id_table	= imx_dma_devtype,
1236 	.remove		= imxdma_remove,
1237 };
1238 
1239 static int __init imxdma_module_init(void)
1240 {
1241 	return platform_driver_probe(&imxdma_driver, imxdma_probe);
1242 }
1243 subsys_initcall(imxdma_module_init);
1244 
1245 MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
1246 MODULE_DESCRIPTION("i.MX dma driver");
1247 MODULE_LICENSE("GPL");
1248