xref: /openbmc/linux/drivers/dma/imx-dma.c (revision 8bd1369b)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // drivers/dma/imx-dma.c
4 //
5 // This file contains a driver for the Freescale i.MX DMA engine
6 // found on i.MX1/21/27
7 //
8 // Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
9 // Copyright 2012 Javier Martin, Vista Silicon <javier.martin@vista-silicon.com>
10 
11 #include <linux/err.h>
12 #include <linux/init.h>
13 #include <linux/types.h>
14 #include <linux/mm.h>
15 #include <linux/interrupt.h>
16 #include <linux/spinlock.h>
17 #include <linux/device.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/slab.h>
20 #include <linux/platform_device.h>
21 #include <linux/clk.h>
22 #include <linux/dmaengine.h>
23 #include <linux/module.h>
24 #include <linux/of_device.h>
25 #include <linux/of_dma.h>
26 
27 #include <asm/irq.h>
28 #include <linux/platform_data/dma-imx.h>
29 
30 #include "dmaengine.h"
31 #define IMXDMA_MAX_CHAN_DESCRIPTORS	16
32 #define IMX_DMA_CHANNELS  16
33 
34 #define IMX_DMA_2D_SLOTS	2
35 #define IMX_DMA_2D_SLOT_A	0
36 #define IMX_DMA_2D_SLOT_B	1
37 
38 #define IMX_DMA_LENGTH_LOOP	((unsigned int)-1)
39 #define IMX_DMA_MEMSIZE_32	(0 << 4)
40 #define IMX_DMA_MEMSIZE_8	(1 << 4)
41 #define IMX_DMA_MEMSIZE_16	(2 << 4)
42 #define IMX_DMA_TYPE_LINEAR	(0 << 10)
43 #define IMX_DMA_TYPE_2D		(1 << 10)
44 #define IMX_DMA_TYPE_FIFO	(2 << 10)
45 
46 #define IMX_DMA_ERR_BURST     (1 << 0)
47 #define IMX_DMA_ERR_REQUEST   (1 << 1)
48 #define IMX_DMA_ERR_TRANSFER  (1 << 2)
49 #define IMX_DMA_ERR_BUFFER    (1 << 3)
50 #define IMX_DMA_ERR_TIMEOUT   (1 << 4)
51 
52 #define DMA_DCR     0x00		/* Control Register */
53 #define DMA_DISR    0x04		/* Interrupt status Register */
54 #define DMA_DIMR    0x08		/* Interrupt mask Register */
55 #define DMA_DBTOSR  0x0c		/* Burst timeout status Register */
56 #define DMA_DRTOSR  0x10		/* Request timeout Register */
57 #define DMA_DSESR   0x14		/* Transfer Error Status Register */
58 #define DMA_DBOSR   0x18		/* Buffer overflow status Register */
59 #define DMA_DBTOCR  0x1c		/* Burst timeout control Register */
60 #define DMA_WSRA    0x40		/* W-Size Register A */
61 #define DMA_XSRA    0x44		/* X-Size Register A */
62 #define DMA_YSRA    0x48		/* Y-Size Register A */
63 #define DMA_WSRB    0x4c		/* W-Size Register B */
64 #define DMA_XSRB    0x50		/* X-Size Register B */
65 #define DMA_YSRB    0x54		/* Y-Size Register B */
66 #define DMA_SAR(x)  (0x80 + ((x) << 6))	/* Source Address Registers */
67 #define DMA_DAR(x)  (0x84 + ((x) << 6))	/* Destination Address Registers */
68 #define DMA_CNTR(x) (0x88 + ((x) << 6))	/* Count Registers */
69 #define DMA_CCR(x)  (0x8c + ((x) << 6))	/* Control Registers */
70 #define DMA_RSSR(x) (0x90 + ((x) << 6))	/* Request source select Registers */
71 #define DMA_BLR(x)  (0x94 + ((x) << 6))	/* Burst length Registers */
72 #define DMA_RTOR(x) (0x98 + ((x) << 6))	/* Request timeout Registers */
73 #define DMA_BUCR(x) (0x98 + ((x) << 6))	/* Bus Utilization Registers */
74 #define DMA_CCNR(x) (0x9C + ((x) << 6))	/* Channel counter Registers */
75 
76 #define DCR_DRST           (1<<1)
77 #define DCR_DEN            (1<<0)
78 #define DBTOCR_EN          (1<<15)
79 #define DBTOCR_CNT(x)      ((x) & 0x7fff)
80 #define CNTR_CNT(x)        ((x) & 0xffffff)
81 #define CCR_ACRPT          (1<<14)
82 #define CCR_DMOD_LINEAR    (0x0 << 12)
83 #define CCR_DMOD_2D        (0x1 << 12)
84 #define CCR_DMOD_FIFO      (0x2 << 12)
85 #define CCR_DMOD_EOBFIFO   (0x3 << 12)
86 #define CCR_SMOD_LINEAR    (0x0 << 10)
87 #define CCR_SMOD_2D        (0x1 << 10)
88 #define CCR_SMOD_FIFO      (0x2 << 10)
89 #define CCR_SMOD_EOBFIFO   (0x3 << 10)
90 #define CCR_MDIR_DEC       (1<<9)
91 #define CCR_MSEL_B         (1<<8)
92 #define CCR_DSIZ_32        (0x0 << 6)
93 #define CCR_DSIZ_8         (0x1 << 6)
94 #define CCR_DSIZ_16        (0x2 << 6)
95 #define CCR_SSIZ_32        (0x0 << 4)
96 #define CCR_SSIZ_8         (0x1 << 4)
97 #define CCR_SSIZ_16        (0x2 << 4)
98 #define CCR_REN            (1<<3)
99 #define CCR_RPT            (1<<2)
100 #define CCR_FRC            (1<<1)
101 #define CCR_CEN            (1<<0)
102 #define RTOR_EN            (1<<15)
103 #define RTOR_CLK           (1<<14)
104 #define RTOR_PSC           (1<<13)
105 
106 enum  imxdma_prep_type {
107 	IMXDMA_DESC_MEMCPY,
108 	IMXDMA_DESC_INTERLEAVED,
109 	IMXDMA_DESC_SLAVE_SG,
110 	IMXDMA_DESC_CYCLIC,
111 };
112 
113 struct imx_dma_2d_config {
114 	u16		xsr;
115 	u16		ysr;
116 	u16		wsr;
117 	int		count;
118 };
119 
120 struct imxdma_desc {
121 	struct list_head		node;
122 	struct dma_async_tx_descriptor	desc;
123 	enum dma_status			status;
124 	dma_addr_t			src;
125 	dma_addr_t			dest;
126 	size_t				len;
127 	enum dma_transfer_direction	direction;
128 	enum imxdma_prep_type		type;
129 	/* For memcpy and interleaved */
130 	unsigned int			config_port;
131 	unsigned int			config_mem;
132 	/* For interleaved transfers */
133 	unsigned int			x;
134 	unsigned int			y;
135 	unsigned int			w;
136 	/* For slave sg and cyclic */
137 	struct scatterlist		*sg;
138 	unsigned int			sgcount;
139 };
140 
141 struct imxdma_channel {
142 	int				hw_chaining;
143 	struct timer_list		watchdog;
144 	struct imxdma_engine		*imxdma;
145 	unsigned int			channel;
146 
147 	struct tasklet_struct		dma_tasklet;
148 	struct list_head		ld_free;
149 	struct list_head		ld_queue;
150 	struct list_head		ld_active;
151 	int				descs_allocated;
152 	enum dma_slave_buswidth		word_size;
153 	dma_addr_t			per_address;
154 	u32				watermark_level;
155 	struct dma_chan			chan;
156 	struct dma_async_tx_descriptor	desc;
157 	enum dma_status			status;
158 	int				dma_request;
159 	struct scatterlist		*sg_list;
160 	u32				ccr_from_device;
161 	u32				ccr_to_device;
162 	bool				enabled_2d;
163 	int				slot_2d;
164 	unsigned int			irq;
165 };
166 
167 enum imx_dma_type {
168 	IMX1_DMA,
169 	IMX21_DMA,
170 	IMX27_DMA,
171 };
172 
173 struct imxdma_engine {
174 	struct device			*dev;
175 	struct device_dma_parameters	dma_parms;
176 	struct dma_device		dma_device;
177 	void __iomem			*base;
178 	struct clk			*dma_ahb;
179 	struct clk			*dma_ipg;
180 	spinlock_t			lock;
181 	struct imx_dma_2d_config	slots_2d[IMX_DMA_2D_SLOTS];
182 	struct imxdma_channel		channel[IMX_DMA_CHANNELS];
183 	enum imx_dma_type		devtype;
184 	unsigned int			irq;
185 	unsigned int			irq_err;
186 
187 };
188 
189 struct imxdma_filter_data {
190 	struct imxdma_engine	*imxdma;
191 	int			 request;
192 };
193 
194 static const struct platform_device_id imx_dma_devtype[] = {
195 	{
196 		.name = "imx1-dma",
197 		.driver_data = IMX1_DMA,
198 	}, {
199 		.name = "imx21-dma",
200 		.driver_data = IMX21_DMA,
201 	}, {
202 		.name = "imx27-dma",
203 		.driver_data = IMX27_DMA,
204 	}, {
205 		/* sentinel */
206 	}
207 };
208 MODULE_DEVICE_TABLE(platform, imx_dma_devtype);
209 
210 static const struct of_device_id imx_dma_of_dev_id[] = {
211 	{
212 		.compatible = "fsl,imx1-dma",
213 		.data = &imx_dma_devtype[IMX1_DMA],
214 	}, {
215 		.compatible = "fsl,imx21-dma",
216 		.data = &imx_dma_devtype[IMX21_DMA],
217 	}, {
218 		.compatible = "fsl,imx27-dma",
219 		.data = &imx_dma_devtype[IMX27_DMA],
220 	}, {
221 		/* sentinel */
222 	}
223 };
224 MODULE_DEVICE_TABLE(of, imx_dma_of_dev_id);
225 
226 static inline int is_imx1_dma(struct imxdma_engine *imxdma)
227 {
228 	return imxdma->devtype == IMX1_DMA;
229 }
230 
231 static inline int is_imx27_dma(struct imxdma_engine *imxdma)
232 {
233 	return imxdma->devtype == IMX27_DMA;
234 }
235 
236 static struct imxdma_channel *to_imxdma_chan(struct dma_chan *chan)
237 {
238 	return container_of(chan, struct imxdma_channel, chan);
239 }
240 
241 static inline bool imxdma_chan_is_doing_cyclic(struct imxdma_channel *imxdmac)
242 {
243 	struct imxdma_desc *desc;
244 
245 	if (!list_empty(&imxdmac->ld_active)) {
246 		desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc,
247 					node);
248 		if (desc->type == IMXDMA_DESC_CYCLIC)
249 			return true;
250 	}
251 	return false;
252 }
253 
254 
255 
256 static void imx_dmav1_writel(struct imxdma_engine *imxdma, unsigned val,
257 			     unsigned offset)
258 {
259 	__raw_writel(val, imxdma->base + offset);
260 }
261 
262 static unsigned imx_dmav1_readl(struct imxdma_engine *imxdma, unsigned offset)
263 {
264 	return __raw_readl(imxdma->base + offset);
265 }
266 
267 static int imxdma_hw_chain(struct imxdma_channel *imxdmac)
268 {
269 	struct imxdma_engine *imxdma = imxdmac->imxdma;
270 
271 	if (is_imx27_dma(imxdma))
272 		return imxdmac->hw_chaining;
273 	else
274 		return 0;
275 }
276 
277 /*
278  * imxdma_sg_next - prepare next chunk for scatter-gather DMA emulation
279  */
280 static inline int imxdma_sg_next(struct imxdma_desc *d)
281 {
282 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
283 	struct imxdma_engine *imxdma = imxdmac->imxdma;
284 	struct scatterlist *sg = d->sg;
285 	unsigned long now;
286 
287 	now = min(d->len, sg_dma_len(sg));
288 	if (d->len != IMX_DMA_LENGTH_LOOP)
289 		d->len -= now;
290 
291 	if (d->direction == DMA_DEV_TO_MEM)
292 		imx_dmav1_writel(imxdma, sg->dma_address,
293 				 DMA_DAR(imxdmac->channel));
294 	else
295 		imx_dmav1_writel(imxdma, sg->dma_address,
296 				 DMA_SAR(imxdmac->channel));
297 
298 	imx_dmav1_writel(imxdma, now, DMA_CNTR(imxdmac->channel));
299 
300 	dev_dbg(imxdma->dev, " %s channel: %d dst 0x%08x, src 0x%08x, "
301 		"size 0x%08x\n", __func__, imxdmac->channel,
302 		 imx_dmav1_readl(imxdma, DMA_DAR(imxdmac->channel)),
303 		 imx_dmav1_readl(imxdma, DMA_SAR(imxdmac->channel)),
304 		 imx_dmav1_readl(imxdma, DMA_CNTR(imxdmac->channel)));
305 
306 	return now;
307 }
308 
309 static void imxdma_enable_hw(struct imxdma_desc *d)
310 {
311 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
312 	struct imxdma_engine *imxdma = imxdmac->imxdma;
313 	int channel = imxdmac->channel;
314 	unsigned long flags;
315 
316 	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
317 
318 	local_irq_save(flags);
319 
320 	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
321 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) &
322 			 ~(1 << channel), DMA_DIMR);
323 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) |
324 			 CCR_CEN | CCR_ACRPT, DMA_CCR(channel));
325 
326 	if (!is_imx1_dma(imxdma) &&
327 			d->sg && imxdma_hw_chain(imxdmac)) {
328 		d->sg = sg_next(d->sg);
329 		if (d->sg) {
330 			u32 tmp;
331 			imxdma_sg_next(d);
332 			tmp = imx_dmav1_readl(imxdma, DMA_CCR(channel));
333 			imx_dmav1_writel(imxdma, tmp | CCR_RPT | CCR_ACRPT,
334 					 DMA_CCR(channel));
335 		}
336 	}
337 
338 	local_irq_restore(flags);
339 }
340 
341 static void imxdma_disable_hw(struct imxdma_channel *imxdmac)
342 {
343 	struct imxdma_engine *imxdma = imxdmac->imxdma;
344 	int channel = imxdmac->channel;
345 	unsigned long flags;
346 
347 	dev_dbg(imxdma->dev, "%s channel %d\n", __func__, channel);
348 
349 	if (imxdma_hw_chain(imxdmac))
350 		del_timer(&imxdmac->watchdog);
351 
352 	local_irq_save(flags);
353 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_DIMR) |
354 			 (1 << channel), DMA_DIMR);
355 	imx_dmav1_writel(imxdma, imx_dmav1_readl(imxdma, DMA_CCR(channel)) &
356 			 ~CCR_CEN, DMA_CCR(channel));
357 	imx_dmav1_writel(imxdma, 1 << channel, DMA_DISR);
358 	local_irq_restore(flags);
359 }
360 
361 static void imxdma_watchdog(struct timer_list *t)
362 {
363 	struct imxdma_channel *imxdmac = from_timer(imxdmac, t, watchdog);
364 	struct imxdma_engine *imxdma = imxdmac->imxdma;
365 	int channel = imxdmac->channel;
366 
367 	imx_dmav1_writel(imxdma, 0, DMA_CCR(channel));
368 
369 	/* Tasklet watchdog error handler */
370 	tasklet_schedule(&imxdmac->dma_tasklet);
371 	dev_dbg(imxdma->dev, "channel %d: watchdog timeout!\n",
372 		imxdmac->channel);
373 }
374 
375 static irqreturn_t imxdma_err_handler(int irq, void *dev_id)
376 {
377 	struct imxdma_engine *imxdma = dev_id;
378 	unsigned int err_mask;
379 	int i, disr;
380 	int errcode;
381 
382 	disr = imx_dmav1_readl(imxdma, DMA_DISR);
383 
384 	err_mask = imx_dmav1_readl(imxdma, DMA_DBTOSR) |
385 		   imx_dmav1_readl(imxdma, DMA_DRTOSR) |
386 		   imx_dmav1_readl(imxdma, DMA_DSESR)  |
387 		   imx_dmav1_readl(imxdma, DMA_DBOSR);
388 
389 	if (!err_mask)
390 		return IRQ_HANDLED;
391 
392 	imx_dmav1_writel(imxdma, disr & err_mask, DMA_DISR);
393 
394 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
395 		if (!(err_mask & (1 << i)))
396 			continue;
397 		errcode = 0;
398 
399 		if (imx_dmav1_readl(imxdma, DMA_DBTOSR) & (1 << i)) {
400 			imx_dmav1_writel(imxdma, 1 << i, DMA_DBTOSR);
401 			errcode |= IMX_DMA_ERR_BURST;
402 		}
403 		if (imx_dmav1_readl(imxdma, DMA_DRTOSR) & (1 << i)) {
404 			imx_dmav1_writel(imxdma, 1 << i, DMA_DRTOSR);
405 			errcode |= IMX_DMA_ERR_REQUEST;
406 		}
407 		if (imx_dmav1_readl(imxdma, DMA_DSESR) & (1 << i)) {
408 			imx_dmav1_writel(imxdma, 1 << i, DMA_DSESR);
409 			errcode |= IMX_DMA_ERR_TRANSFER;
410 		}
411 		if (imx_dmav1_readl(imxdma, DMA_DBOSR) & (1 << i)) {
412 			imx_dmav1_writel(imxdma, 1 << i, DMA_DBOSR);
413 			errcode |= IMX_DMA_ERR_BUFFER;
414 		}
415 		/* Tasklet error handler */
416 		tasklet_schedule(&imxdma->channel[i].dma_tasklet);
417 
418 		dev_warn(imxdma->dev,
419 			 "DMA timeout on channel %d -%s%s%s%s\n", i,
420 			 errcode & IMX_DMA_ERR_BURST ?    " burst" : "",
421 			 errcode & IMX_DMA_ERR_REQUEST ?  " request" : "",
422 			 errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "",
423 			 errcode & IMX_DMA_ERR_BUFFER ?   " buffer" : "");
424 	}
425 	return IRQ_HANDLED;
426 }
427 
428 static void dma_irq_handle_channel(struct imxdma_channel *imxdmac)
429 {
430 	struct imxdma_engine *imxdma = imxdmac->imxdma;
431 	int chno = imxdmac->channel;
432 	struct imxdma_desc *desc;
433 	unsigned long flags;
434 
435 	spin_lock_irqsave(&imxdma->lock, flags);
436 	if (list_empty(&imxdmac->ld_active)) {
437 		spin_unlock_irqrestore(&imxdma->lock, flags);
438 		goto out;
439 	}
440 
441 	desc = list_first_entry(&imxdmac->ld_active,
442 				struct imxdma_desc,
443 				node);
444 	spin_unlock_irqrestore(&imxdma->lock, flags);
445 
446 	if (desc->sg) {
447 		u32 tmp;
448 		desc->sg = sg_next(desc->sg);
449 
450 		if (desc->sg) {
451 			imxdma_sg_next(desc);
452 
453 			tmp = imx_dmav1_readl(imxdma, DMA_CCR(chno));
454 
455 			if (imxdma_hw_chain(imxdmac)) {
456 				/* FIXME: The timeout should probably be
457 				 * configurable
458 				 */
459 				mod_timer(&imxdmac->watchdog,
460 					jiffies + msecs_to_jiffies(500));
461 
462 				tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT;
463 				imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
464 			} else {
465 				imx_dmav1_writel(imxdma, tmp & ~CCR_CEN,
466 						 DMA_CCR(chno));
467 				tmp |= CCR_CEN;
468 			}
469 
470 			imx_dmav1_writel(imxdma, tmp, DMA_CCR(chno));
471 
472 			if (imxdma_chan_is_doing_cyclic(imxdmac))
473 				/* Tasklet progression */
474 				tasklet_schedule(&imxdmac->dma_tasklet);
475 
476 			return;
477 		}
478 
479 		if (imxdma_hw_chain(imxdmac)) {
480 			del_timer(&imxdmac->watchdog);
481 			return;
482 		}
483 	}
484 
485 out:
486 	imx_dmav1_writel(imxdma, 0, DMA_CCR(chno));
487 	/* Tasklet irq */
488 	tasklet_schedule(&imxdmac->dma_tasklet);
489 }
490 
491 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
492 {
493 	struct imxdma_engine *imxdma = dev_id;
494 	int i, disr;
495 
496 	if (!is_imx1_dma(imxdma))
497 		imxdma_err_handler(irq, dev_id);
498 
499 	disr = imx_dmav1_readl(imxdma, DMA_DISR);
500 
501 	dev_dbg(imxdma->dev, "%s called, disr=0x%08x\n", __func__, disr);
502 
503 	imx_dmav1_writel(imxdma, disr, DMA_DISR);
504 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
505 		if (disr & (1 << i))
506 			dma_irq_handle_channel(&imxdma->channel[i]);
507 	}
508 
509 	return IRQ_HANDLED;
510 }
511 
512 static int imxdma_xfer_desc(struct imxdma_desc *d)
513 {
514 	struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
515 	struct imxdma_engine *imxdma = imxdmac->imxdma;
516 	int slot = -1;
517 	int i;
518 
519 	/* Configure and enable */
520 	switch (d->type) {
521 	case IMXDMA_DESC_INTERLEAVED:
522 		/* Try to get a free 2D slot */
523 		for (i = 0; i < IMX_DMA_2D_SLOTS; i++) {
524 			if ((imxdma->slots_2d[i].count > 0) &&
525 			((imxdma->slots_2d[i].xsr != d->x) ||
526 			(imxdma->slots_2d[i].ysr != d->y) ||
527 			(imxdma->slots_2d[i].wsr != d->w)))
528 				continue;
529 			slot = i;
530 			break;
531 		}
532 		if (slot < 0)
533 			return -EBUSY;
534 
535 		imxdma->slots_2d[slot].xsr = d->x;
536 		imxdma->slots_2d[slot].ysr = d->y;
537 		imxdma->slots_2d[slot].wsr = d->w;
538 		imxdma->slots_2d[slot].count++;
539 
540 		imxdmac->slot_2d = slot;
541 		imxdmac->enabled_2d = true;
542 
543 		if (slot == IMX_DMA_2D_SLOT_A) {
544 			d->config_mem &= ~CCR_MSEL_B;
545 			d->config_port &= ~CCR_MSEL_B;
546 			imx_dmav1_writel(imxdma, d->x, DMA_XSRA);
547 			imx_dmav1_writel(imxdma, d->y, DMA_YSRA);
548 			imx_dmav1_writel(imxdma, d->w, DMA_WSRA);
549 		} else {
550 			d->config_mem |= CCR_MSEL_B;
551 			d->config_port |= CCR_MSEL_B;
552 			imx_dmav1_writel(imxdma, d->x, DMA_XSRB);
553 			imx_dmav1_writel(imxdma, d->y, DMA_YSRB);
554 			imx_dmav1_writel(imxdma, d->w, DMA_WSRB);
555 		}
556 		/*
557 		 * We fall-through here intentionally, since a 2D transfer is
558 		 * similar to MEMCPY just adding the 2D slot configuration.
559 		 */
560 	case IMXDMA_DESC_MEMCPY:
561 		imx_dmav1_writel(imxdma, d->src, DMA_SAR(imxdmac->channel));
562 		imx_dmav1_writel(imxdma, d->dest, DMA_DAR(imxdmac->channel));
563 		imx_dmav1_writel(imxdma, d->config_mem | (d->config_port << 2),
564 			 DMA_CCR(imxdmac->channel));
565 
566 		imx_dmav1_writel(imxdma, d->len, DMA_CNTR(imxdmac->channel));
567 
568 		dev_dbg(imxdma->dev,
569 			"%s channel: %d dest=0x%08llx src=0x%08llx dma_length=%zu\n",
570 			__func__, imxdmac->channel,
571 			(unsigned long long)d->dest,
572 			(unsigned long long)d->src, d->len);
573 
574 		break;
575 	/* Cyclic transfer is the same as slave_sg with special sg configuration. */
576 	case IMXDMA_DESC_CYCLIC:
577 	case IMXDMA_DESC_SLAVE_SG:
578 		if (d->direction == DMA_DEV_TO_MEM) {
579 			imx_dmav1_writel(imxdma, imxdmac->per_address,
580 					 DMA_SAR(imxdmac->channel));
581 			imx_dmav1_writel(imxdma, imxdmac->ccr_from_device,
582 					 DMA_CCR(imxdmac->channel));
583 
584 			dev_dbg(imxdma->dev,
585 				"%s channel: %d sg=%p sgcount=%d total length=%zu dev_addr=0x%08llx (dev2mem)\n",
586 				__func__, imxdmac->channel,
587 				d->sg, d->sgcount, d->len,
588 				(unsigned long long)imxdmac->per_address);
589 		} else if (d->direction == DMA_MEM_TO_DEV) {
590 			imx_dmav1_writel(imxdma, imxdmac->per_address,
591 					 DMA_DAR(imxdmac->channel));
592 			imx_dmav1_writel(imxdma, imxdmac->ccr_to_device,
593 					 DMA_CCR(imxdmac->channel));
594 
595 			dev_dbg(imxdma->dev,
596 				"%s channel: %d sg=%p sgcount=%d total length=%zu dev_addr=0x%08llx (mem2dev)\n",
597 				__func__, imxdmac->channel,
598 				d->sg, d->sgcount, d->len,
599 				(unsigned long long)imxdmac->per_address);
600 		} else {
601 			dev_err(imxdma->dev, "%s channel: %d bad dma mode\n",
602 				__func__, imxdmac->channel);
603 			return -EINVAL;
604 		}
605 
606 		imxdma_sg_next(d);
607 
608 		break;
609 	default:
610 		return -EINVAL;
611 	}
612 	imxdma_enable_hw(d);
613 	return 0;
614 }
615 
616 static void imxdma_tasklet(unsigned long data)
617 {
618 	struct imxdma_channel *imxdmac = (void *)data;
619 	struct imxdma_engine *imxdma = imxdmac->imxdma;
620 	struct imxdma_desc *desc;
621 	unsigned long flags;
622 
623 	spin_lock_irqsave(&imxdma->lock, flags);
624 
625 	if (list_empty(&imxdmac->ld_active)) {
626 		/* Someone might have called terminate all */
627 		spin_unlock_irqrestore(&imxdma->lock, flags);
628 		return;
629 	}
630 	desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc, node);
631 
632 	/* If we are dealing with a cyclic descriptor, keep it on ld_active
633 	 * and dont mark the descriptor as complete.
634 	 * Only in non-cyclic cases it would be marked as complete
635 	 */
636 	if (imxdma_chan_is_doing_cyclic(imxdmac))
637 		goto out;
638 	else
639 		dma_cookie_complete(&desc->desc);
640 
641 	/* Free 2D slot if it was an interleaved transfer */
642 	if (imxdmac->enabled_2d) {
643 		imxdma->slots_2d[imxdmac->slot_2d].count--;
644 		imxdmac->enabled_2d = false;
645 	}
646 
647 	list_move_tail(imxdmac->ld_active.next, &imxdmac->ld_free);
648 
649 	if (!list_empty(&imxdmac->ld_queue)) {
650 		desc = list_first_entry(&imxdmac->ld_queue, struct imxdma_desc,
651 					node);
652 		list_move_tail(imxdmac->ld_queue.next, &imxdmac->ld_active);
653 		if (imxdma_xfer_desc(desc) < 0)
654 			dev_warn(imxdma->dev, "%s: channel: %d couldn't xfer desc\n",
655 				 __func__, imxdmac->channel);
656 	}
657 out:
658 	spin_unlock_irqrestore(&imxdma->lock, flags);
659 
660 	dmaengine_desc_get_callback_invoke(&desc->desc, NULL);
661 }
662 
663 static int imxdma_terminate_all(struct dma_chan *chan)
664 {
665 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
666 	struct imxdma_engine *imxdma = imxdmac->imxdma;
667 	unsigned long flags;
668 
669 	imxdma_disable_hw(imxdmac);
670 
671 	spin_lock_irqsave(&imxdma->lock, flags);
672 	list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
673 	list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
674 	spin_unlock_irqrestore(&imxdma->lock, flags);
675 	return 0;
676 }
677 
678 static int imxdma_config(struct dma_chan *chan,
679 			 struct dma_slave_config *dmaengine_cfg)
680 {
681 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
682 	struct imxdma_engine *imxdma = imxdmac->imxdma;
683 	unsigned int mode = 0;
684 
685 	if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
686 		imxdmac->per_address = dmaengine_cfg->src_addr;
687 		imxdmac->watermark_level = dmaengine_cfg->src_maxburst;
688 		imxdmac->word_size = dmaengine_cfg->src_addr_width;
689 	} else {
690 		imxdmac->per_address = dmaengine_cfg->dst_addr;
691 		imxdmac->watermark_level = dmaengine_cfg->dst_maxburst;
692 		imxdmac->word_size = dmaengine_cfg->dst_addr_width;
693 	}
694 
695 	switch (imxdmac->word_size) {
696 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
697 		mode = IMX_DMA_MEMSIZE_8;
698 		break;
699 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
700 		mode = IMX_DMA_MEMSIZE_16;
701 		break;
702 	default:
703 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
704 		mode = IMX_DMA_MEMSIZE_32;
705 		break;
706 	}
707 
708 	imxdmac->hw_chaining = 0;
709 
710 	imxdmac->ccr_from_device = (mode | IMX_DMA_TYPE_FIFO) |
711 		((IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) << 2) |
712 		CCR_REN;
713 	imxdmac->ccr_to_device =
714 		(IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) |
715 		((mode | IMX_DMA_TYPE_FIFO) << 2) | CCR_REN;
716 	imx_dmav1_writel(imxdma, imxdmac->dma_request,
717 			 DMA_RSSR(imxdmac->channel));
718 
719 	/* Set burst length */
720 	imx_dmav1_writel(imxdma, imxdmac->watermark_level *
721 			 imxdmac->word_size, DMA_BLR(imxdmac->channel));
722 
723 	return 0;
724 }
725 
726 static enum dma_status imxdma_tx_status(struct dma_chan *chan,
727 					    dma_cookie_t cookie,
728 					    struct dma_tx_state *txstate)
729 {
730 	return dma_cookie_status(chan, cookie, txstate);
731 }
732 
733 static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
734 {
735 	struct imxdma_channel *imxdmac = to_imxdma_chan(tx->chan);
736 	struct imxdma_engine *imxdma = imxdmac->imxdma;
737 	dma_cookie_t cookie;
738 	unsigned long flags;
739 
740 	spin_lock_irqsave(&imxdma->lock, flags);
741 	list_move_tail(imxdmac->ld_free.next, &imxdmac->ld_queue);
742 	cookie = dma_cookie_assign(tx);
743 	spin_unlock_irqrestore(&imxdma->lock, flags);
744 
745 	return cookie;
746 }
747 
748 static int imxdma_alloc_chan_resources(struct dma_chan *chan)
749 {
750 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
751 	struct imx_dma_data *data = chan->private;
752 
753 	if (data != NULL)
754 		imxdmac->dma_request = data->dma_request;
755 
756 	while (imxdmac->descs_allocated < IMXDMA_MAX_CHAN_DESCRIPTORS) {
757 		struct imxdma_desc *desc;
758 
759 		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
760 		if (!desc)
761 			break;
762 		memset(&desc->desc, 0, sizeof(struct dma_async_tx_descriptor));
763 		dma_async_tx_descriptor_init(&desc->desc, chan);
764 		desc->desc.tx_submit = imxdma_tx_submit;
765 		/* txd.flags will be overwritten in prep funcs */
766 		desc->desc.flags = DMA_CTRL_ACK;
767 		desc->status = DMA_COMPLETE;
768 
769 		list_add_tail(&desc->node, &imxdmac->ld_free);
770 		imxdmac->descs_allocated++;
771 	}
772 
773 	if (!imxdmac->descs_allocated)
774 		return -ENOMEM;
775 
776 	return imxdmac->descs_allocated;
777 }
778 
779 static void imxdma_free_chan_resources(struct dma_chan *chan)
780 {
781 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
782 	struct imxdma_engine *imxdma = imxdmac->imxdma;
783 	struct imxdma_desc *desc, *_desc;
784 	unsigned long flags;
785 
786 	spin_lock_irqsave(&imxdma->lock, flags);
787 
788 	imxdma_disable_hw(imxdmac);
789 	list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
790 	list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
791 
792 	spin_unlock_irqrestore(&imxdma->lock, flags);
793 
794 	list_for_each_entry_safe(desc, _desc, &imxdmac->ld_free, node) {
795 		kfree(desc);
796 		imxdmac->descs_allocated--;
797 	}
798 	INIT_LIST_HEAD(&imxdmac->ld_free);
799 
800 	kfree(imxdmac->sg_list);
801 	imxdmac->sg_list = NULL;
802 }
803 
804 static struct dma_async_tx_descriptor *imxdma_prep_slave_sg(
805 		struct dma_chan *chan, struct scatterlist *sgl,
806 		unsigned int sg_len, enum dma_transfer_direction direction,
807 		unsigned long flags, void *context)
808 {
809 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
810 	struct scatterlist *sg;
811 	int i, dma_length = 0;
812 	struct imxdma_desc *desc;
813 
814 	if (list_empty(&imxdmac->ld_free) ||
815 	    imxdma_chan_is_doing_cyclic(imxdmac))
816 		return NULL;
817 
818 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
819 
820 	for_each_sg(sgl, sg, sg_len, i) {
821 		dma_length += sg_dma_len(sg);
822 	}
823 
824 	switch (imxdmac->word_size) {
825 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
826 		if (sg_dma_len(sgl) & 3 || sgl->dma_address & 3)
827 			return NULL;
828 		break;
829 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
830 		if (sg_dma_len(sgl) & 1 || sgl->dma_address & 1)
831 			return NULL;
832 		break;
833 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
834 		break;
835 	default:
836 		return NULL;
837 	}
838 
839 	desc->type = IMXDMA_DESC_SLAVE_SG;
840 	desc->sg = sgl;
841 	desc->sgcount = sg_len;
842 	desc->len = dma_length;
843 	desc->direction = direction;
844 	if (direction == DMA_DEV_TO_MEM) {
845 		desc->src = imxdmac->per_address;
846 	} else {
847 		desc->dest = imxdmac->per_address;
848 	}
849 	desc->desc.callback = NULL;
850 	desc->desc.callback_param = NULL;
851 
852 	return &desc->desc;
853 }
854 
855 static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
856 		struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
857 		size_t period_len, enum dma_transfer_direction direction,
858 		unsigned long flags)
859 {
860 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
861 	struct imxdma_engine *imxdma = imxdmac->imxdma;
862 	struct imxdma_desc *desc;
863 	int i;
864 	unsigned int periods = buf_len / period_len;
865 
866 	dev_dbg(imxdma->dev, "%s channel: %d buf_len=%zu period_len=%zu\n",
867 			__func__, imxdmac->channel, buf_len, period_len);
868 
869 	if (list_empty(&imxdmac->ld_free) ||
870 	    imxdma_chan_is_doing_cyclic(imxdmac))
871 		return NULL;
872 
873 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
874 
875 	kfree(imxdmac->sg_list);
876 
877 	imxdmac->sg_list = kcalloc(periods + 1,
878 			sizeof(struct scatterlist), GFP_ATOMIC);
879 	if (!imxdmac->sg_list)
880 		return NULL;
881 
882 	sg_init_table(imxdmac->sg_list, periods);
883 
884 	for (i = 0; i < periods; i++) {
885 		sg_assign_page(&imxdmac->sg_list[i], NULL);
886 		imxdmac->sg_list[i].offset = 0;
887 		imxdmac->sg_list[i].dma_address = dma_addr;
888 		sg_dma_len(&imxdmac->sg_list[i]) = period_len;
889 		dma_addr += period_len;
890 	}
891 
892 	/* close the loop */
893 	sg_chain(imxdmac->sg_list, periods + 1, imxdmac->sg_list);
894 
895 	desc->type = IMXDMA_DESC_CYCLIC;
896 	desc->sg = imxdmac->sg_list;
897 	desc->sgcount = periods;
898 	desc->len = IMX_DMA_LENGTH_LOOP;
899 	desc->direction = direction;
900 	if (direction == DMA_DEV_TO_MEM) {
901 		desc->src = imxdmac->per_address;
902 	} else {
903 		desc->dest = imxdmac->per_address;
904 	}
905 	desc->desc.callback = NULL;
906 	desc->desc.callback_param = NULL;
907 
908 	return &desc->desc;
909 }
910 
911 static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
912 	struct dma_chan *chan, dma_addr_t dest,
913 	dma_addr_t src, size_t len, unsigned long flags)
914 {
915 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
916 	struct imxdma_engine *imxdma = imxdmac->imxdma;
917 	struct imxdma_desc *desc;
918 
919 	dev_dbg(imxdma->dev, "%s channel: %d src=0x%llx dst=0x%llx len=%zu\n",
920 		__func__, imxdmac->channel, (unsigned long long)src,
921 		(unsigned long long)dest, len);
922 
923 	if (list_empty(&imxdmac->ld_free) ||
924 	    imxdma_chan_is_doing_cyclic(imxdmac))
925 		return NULL;
926 
927 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
928 
929 	desc->type = IMXDMA_DESC_MEMCPY;
930 	desc->src = src;
931 	desc->dest = dest;
932 	desc->len = len;
933 	desc->direction = DMA_MEM_TO_MEM;
934 	desc->config_port = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
935 	desc->config_mem = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
936 	desc->desc.callback = NULL;
937 	desc->desc.callback_param = NULL;
938 
939 	return &desc->desc;
940 }
941 
942 static struct dma_async_tx_descriptor *imxdma_prep_dma_interleaved(
943 	struct dma_chan *chan, struct dma_interleaved_template *xt,
944 	unsigned long flags)
945 {
946 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
947 	struct imxdma_engine *imxdma = imxdmac->imxdma;
948 	struct imxdma_desc *desc;
949 
950 	dev_dbg(imxdma->dev, "%s channel: %d src_start=0x%llx dst_start=0x%llx\n"
951 		"   src_sgl=%s dst_sgl=%s numf=%zu frame_size=%zu\n", __func__,
952 		imxdmac->channel, (unsigned long long)xt->src_start,
953 		(unsigned long long) xt->dst_start,
954 		xt->src_sgl ? "true" : "false", xt->dst_sgl ? "true" : "false",
955 		xt->numf, xt->frame_size);
956 
957 	if (list_empty(&imxdmac->ld_free) ||
958 	    imxdma_chan_is_doing_cyclic(imxdmac))
959 		return NULL;
960 
961 	if (xt->frame_size != 1 || xt->numf <= 0 || xt->dir != DMA_MEM_TO_MEM)
962 		return NULL;
963 
964 	desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
965 
966 	desc->type = IMXDMA_DESC_INTERLEAVED;
967 	desc->src = xt->src_start;
968 	desc->dest = xt->dst_start;
969 	desc->x = xt->sgl[0].size;
970 	desc->y = xt->numf;
971 	desc->w = xt->sgl[0].icg + desc->x;
972 	desc->len = desc->x * desc->y;
973 	desc->direction = DMA_MEM_TO_MEM;
974 	desc->config_port = IMX_DMA_MEMSIZE_32;
975 	desc->config_mem = IMX_DMA_MEMSIZE_32;
976 	if (xt->src_sgl)
977 		desc->config_mem |= IMX_DMA_TYPE_2D;
978 	if (xt->dst_sgl)
979 		desc->config_port |= IMX_DMA_TYPE_2D;
980 	desc->desc.callback = NULL;
981 	desc->desc.callback_param = NULL;
982 
983 	return &desc->desc;
984 }
985 
986 static void imxdma_issue_pending(struct dma_chan *chan)
987 {
988 	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
989 	struct imxdma_engine *imxdma = imxdmac->imxdma;
990 	struct imxdma_desc *desc;
991 	unsigned long flags;
992 
993 	spin_lock_irqsave(&imxdma->lock, flags);
994 	if (list_empty(&imxdmac->ld_active) &&
995 	    !list_empty(&imxdmac->ld_queue)) {
996 		desc = list_first_entry(&imxdmac->ld_queue,
997 					struct imxdma_desc, node);
998 
999 		if (imxdma_xfer_desc(desc) < 0) {
1000 			dev_warn(imxdma->dev,
1001 				 "%s: channel: %d couldn't issue DMA xfer\n",
1002 				 __func__, imxdmac->channel);
1003 		} else {
1004 			list_move_tail(imxdmac->ld_queue.next,
1005 				       &imxdmac->ld_active);
1006 		}
1007 	}
1008 	spin_unlock_irqrestore(&imxdma->lock, flags);
1009 }
1010 
1011 static bool imxdma_filter_fn(struct dma_chan *chan, void *param)
1012 {
1013 	struct imxdma_filter_data *fdata = param;
1014 	struct imxdma_channel *imxdma_chan = to_imxdma_chan(chan);
1015 
1016 	if (chan->device->dev != fdata->imxdma->dev)
1017 		return false;
1018 
1019 	imxdma_chan->dma_request = fdata->request;
1020 	chan->private = NULL;
1021 
1022 	return true;
1023 }
1024 
1025 static struct dma_chan *imxdma_xlate(struct of_phandle_args *dma_spec,
1026 						struct of_dma *ofdma)
1027 {
1028 	int count = dma_spec->args_count;
1029 	struct imxdma_engine *imxdma = ofdma->of_dma_data;
1030 	struct imxdma_filter_data fdata = {
1031 		.imxdma = imxdma,
1032 	};
1033 
1034 	if (count != 1)
1035 		return NULL;
1036 
1037 	fdata.request = dma_spec->args[0];
1038 
1039 	return dma_request_channel(imxdma->dma_device.cap_mask,
1040 					imxdma_filter_fn, &fdata);
1041 }
1042 
1043 static int __init imxdma_probe(struct platform_device *pdev)
1044 {
1045 	struct imxdma_engine *imxdma;
1046 	struct resource *res;
1047 	const struct of_device_id *of_id;
1048 	int ret, i;
1049 	int irq, irq_err;
1050 
1051 	of_id = of_match_device(imx_dma_of_dev_id, &pdev->dev);
1052 	if (of_id)
1053 		pdev->id_entry = of_id->data;
1054 
1055 	imxdma = devm_kzalloc(&pdev->dev, sizeof(*imxdma), GFP_KERNEL);
1056 	if (!imxdma)
1057 		return -ENOMEM;
1058 
1059 	imxdma->dev = &pdev->dev;
1060 	imxdma->devtype = pdev->id_entry->driver_data;
1061 
1062 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1063 	imxdma->base = devm_ioremap_resource(&pdev->dev, res);
1064 	if (IS_ERR(imxdma->base))
1065 		return PTR_ERR(imxdma->base);
1066 
1067 	irq = platform_get_irq(pdev, 0);
1068 	if (irq < 0)
1069 		return irq;
1070 
1071 	imxdma->dma_ipg = devm_clk_get(&pdev->dev, "ipg");
1072 	if (IS_ERR(imxdma->dma_ipg))
1073 		return PTR_ERR(imxdma->dma_ipg);
1074 
1075 	imxdma->dma_ahb = devm_clk_get(&pdev->dev, "ahb");
1076 	if (IS_ERR(imxdma->dma_ahb))
1077 		return PTR_ERR(imxdma->dma_ahb);
1078 
1079 	ret = clk_prepare_enable(imxdma->dma_ipg);
1080 	if (ret)
1081 		return ret;
1082 	ret = clk_prepare_enable(imxdma->dma_ahb);
1083 	if (ret)
1084 		goto disable_dma_ipg_clk;
1085 
1086 	/* reset DMA module */
1087 	imx_dmav1_writel(imxdma, DCR_DRST, DMA_DCR);
1088 
1089 	if (is_imx1_dma(imxdma)) {
1090 		ret = devm_request_irq(&pdev->dev, irq,
1091 				       dma_irq_handler, 0, "DMA", imxdma);
1092 		if (ret) {
1093 			dev_warn(imxdma->dev, "Can't register IRQ for DMA\n");
1094 			goto disable_dma_ahb_clk;
1095 		}
1096 		imxdma->irq = irq;
1097 
1098 		irq_err = platform_get_irq(pdev, 1);
1099 		if (irq_err < 0) {
1100 			ret = irq_err;
1101 			goto disable_dma_ahb_clk;
1102 		}
1103 
1104 		ret = devm_request_irq(&pdev->dev, irq_err,
1105 				       imxdma_err_handler, 0, "DMA", imxdma);
1106 		if (ret) {
1107 			dev_warn(imxdma->dev, "Can't register ERRIRQ for DMA\n");
1108 			goto disable_dma_ahb_clk;
1109 		}
1110 		imxdma->irq_err = irq_err;
1111 	}
1112 
1113 	/* enable DMA module */
1114 	imx_dmav1_writel(imxdma, DCR_DEN, DMA_DCR);
1115 
1116 	/* clear all interrupts */
1117 	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DISR);
1118 
1119 	/* disable interrupts */
1120 	imx_dmav1_writel(imxdma, (1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR);
1121 
1122 	INIT_LIST_HEAD(&imxdma->dma_device.channels);
1123 
1124 	dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
1125 	dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
1126 	dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
1127 	dma_cap_set(DMA_INTERLEAVE, imxdma->dma_device.cap_mask);
1128 
1129 	/* Initialize 2D global parameters */
1130 	for (i = 0; i < IMX_DMA_2D_SLOTS; i++)
1131 		imxdma->slots_2d[i].count = 0;
1132 
1133 	spin_lock_init(&imxdma->lock);
1134 
1135 	/* Initialize channel parameters */
1136 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
1137 		struct imxdma_channel *imxdmac = &imxdma->channel[i];
1138 
1139 		if (!is_imx1_dma(imxdma)) {
1140 			ret = devm_request_irq(&pdev->dev, irq + i,
1141 					dma_irq_handler, 0, "DMA", imxdma);
1142 			if (ret) {
1143 				dev_warn(imxdma->dev, "Can't register IRQ %d "
1144 					 "for DMA channel %d\n",
1145 					 irq + i, i);
1146 				goto disable_dma_ahb_clk;
1147 			}
1148 
1149 			imxdmac->irq = irq + i;
1150 			timer_setup(&imxdmac->watchdog, imxdma_watchdog, 0);
1151 		}
1152 
1153 		imxdmac->imxdma = imxdma;
1154 
1155 		INIT_LIST_HEAD(&imxdmac->ld_queue);
1156 		INIT_LIST_HEAD(&imxdmac->ld_free);
1157 		INIT_LIST_HEAD(&imxdmac->ld_active);
1158 
1159 		tasklet_init(&imxdmac->dma_tasklet, imxdma_tasklet,
1160 			     (unsigned long)imxdmac);
1161 		imxdmac->chan.device = &imxdma->dma_device;
1162 		dma_cookie_init(&imxdmac->chan);
1163 		imxdmac->channel = i;
1164 
1165 		/* Add the channel to the DMAC list */
1166 		list_add_tail(&imxdmac->chan.device_node,
1167 			      &imxdma->dma_device.channels);
1168 	}
1169 
1170 	imxdma->dma_device.dev = &pdev->dev;
1171 
1172 	imxdma->dma_device.device_alloc_chan_resources = imxdma_alloc_chan_resources;
1173 	imxdma->dma_device.device_free_chan_resources = imxdma_free_chan_resources;
1174 	imxdma->dma_device.device_tx_status = imxdma_tx_status;
1175 	imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
1176 	imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
1177 	imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
1178 	imxdma->dma_device.device_prep_interleaved_dma = imxdma_prep_dma_interleaved;
1179 	imxdma->dma_device.device_config = imxdma_config;
1180 	imxdma->dma_device.device_terminate_all = imxdma_terminate_all;
1181 	imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
1182 
1183 	platform_set_drvdata(pdev, imxdma);
1184 
1185 	imxdma->dma_device.copy_align = DMAENGINE_ALIGN_4_BYTES;
1186 	imxdma->dma_device.dev->dma_parms = &imxdma->dma_parms;
1187 	dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);
1188 
1189 	ret = dma_async_device_register(&imxdma->dma_device);
1190 	if (ret) {
1191 		dev_err(&pdev->dev, "unable to register\n");
1192 		goto disable_dma_ahb_clk;
1193 	}
1194 
1195 	if (pdev->dev.of_node) {
1196 		ret = of_dma_controller_register(pdev->dev.of_node,
1197 				imxdma_xlate, imxdma);
1198 		if (ret) {
1199 			dev_err(&pdev->dev, "unable to register of_dma_controller\n");
1200 			goto err_of_dma_controller;
1201 		}
1202 	}
1203 
1204 	return 0;
1205 
1206 err_of_dma_controller:
1207 	dma_async_device_unregister(&imxdma->dma_device);
1208 disable_dma_ahb_clk:
1209 	clk_disable_unprepare(imxdma->dma_ahb);
1210 disable_dma_ipg_clk:
1211 	clk_disable_unprepare(imxdma->dma_ipg);
1212 	return ret;
1213 }
1214 
1215 static void imxdma_free_irq(struct platform_device *pdev, struct imxdma_engine *imxdma)
1216 {
1217 	int i;
1218 
1219 	if (is_imx1_dma(imxdma)) {
1220 		disable_irq(imxdma->irq);
1221 		disable_irq(imxdma->irq_err);
1222 	}
1223 
1224 	for (i = 0; i < IMX_DMA_CHANNELS; i++) {
1225 		struct imxdma_channel *imxdmac = &imxdma->channel[i];
1226 
1227 		if (!is_imx1_dma(imxdma))
1228 			disable_irq(imxdmac->irq);
1229 
1230 		tasklet_kill(&imxdmac->dma_tasklet);
1231 	}
1232 }
1233 
1234 static int imxdma_remove(struct platform_device *pdev)
1235 {
1236 	struct imxdma_engine *imxdma = platform_get_drvdata(pdev);
1237 
1238 	imxdma_free_irq(pdev, imxdma);
1239 
1240         dma_async_device_unregister(&imxdma->dma_device);
1241 
1242 	if (pdev->dev.of_node)
1243 		of_dma_controller_free(pdev->dev.of_node);
1244 
1245 	clk_disable_unprepare(imxdma->dma_ipg);
1246 	clk_disable_unprepare(imxdma->dma_ahb);
1247 
1248         return 0;
1249 }
1250 
1251 static struct platform_driver imxdma_driver = {
1252 	.driver		= {
1253 		.name	= "imx-dma",
1254 		.of_match_table = imx_dma_of_dev_id,
1255 	},
1256 	.id_table	= imx_dma_devtype,
1257 	.remove		= imxdma_remove,
1258 };
1259 
1260 static int __init imxdma_module_init(void)
1261 {
1262 	return platform_driver_probe(&imxdma_driver, imxdma_probe);
1263 }
1264 subsys_initcall(imxdma_module_init);
1265 
1266 MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
1267 MODULE_DESCRIPTION("i.MX dma driver");
1268 MODULE_LICENSE("GPL");
1269