xref: /linux/drivers/dma/xilinx/zynqmp_dma.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * DMA driver for Xilinx ZynqMP DMA Engine
4  *
5  * Copyright (C) 2016 Xilinx, Inc. All rights reserved.
6  */
7 
8 #include <linux/bitops.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/of_dma.h>
15 #include <linux/of_platform.h>
16 #include <linux/slab.h>
17 #include <linux/clk.h>
18 #include <linux/io-64-nonatomic-lo-hi.h>
19 #include <linux/pm_runtime.h>
20 
21 #include "../dmaengine.h"
22 
23 /* Register Offsets */
24 #define ZYNQMP_DMA_ISR			0x100
25 #define ZYNQMP_DMA_IMR			0x104
26 #define ZYNQMP_DMA_IER			0x108
27 #define ZYNQMP_DMA_IDS			0x10C
28 #define ZYNQMP_DMA_CTRL0		0x110
29 #define ZYNQMP_DMA_CTRL1		0x114
30 #define ZYNQMP_DMA_DATA_ATTR		0x120
31 #define ZYNQMP_DMA_DSCR_ATTR		0x124
32 #define ZYNQMP_DMA_SRC_DSCR_WRD0	0x128
33 #define ZYNQMP_DMA_SRC_DSCR_WRD1	0x12C
34 #define ZYNQMP_DMA_SRC_DSCR_WRD2	0x130
35 #define ZYNQMP_DMA_SRC_DSCR_WRD3	0x134
36 #define ZYNQMP_DMA_DST_DSCR_WRD0	0x138
37 #define ZYNQMP_DMA_DST_DSCR_WRD1	0x13C
38 #define ZYNQMP_DMA_DST_DSCR_WRD2	0x140
39 #define ZYNQMP_DMA_DST_DSCR_WRD3	0x144
40 #define ZYNQMP_DMA_SRC_START_LSB	0x158
41 #define ZYNQMP_DMA_SRC_START_MSB	0x15C
42 #define ZYNQMP_DMA_DST_START_LSB	0x160
43 #define ZYNQMP_DMA_DST_START_MSB	0x164
44 #define ZYNQMP_DMA_TOTAL_BYTE		0x188
45 #define ZYNQMP_DMA_RATE_CTRL		0x18C
46 #define ZYNQMP_DMA_IRQ_SRC_ACCT		0x190
47 #define ZYNQMP_DMA_IRQ_DST_ACCT		0x194
48 #define ZYNQMP_DMA_CTRL2		0x200
49 
50 /* Interrupt registers bit field definitions */
51 #define ZYNQMP_DMA_DONE			BIT(10)
52 #define ZYNQMP_DMA_AXI_WR_DATA		BIT(9)
53 #define ZYNQMP_DMA_AXI_RD_DATA		BIT(8)
54 #define ZYNQMP_DMA_AXI_RD_DST_DSCR	BIT(7)
55 #define ZYNQMP_DMA_AXI_RD_SRC_DSCR	BIT(6)
56 #define ZYNQMP_DMA_IRQ_DST_ACCT_ERR	BIT(5)
57 #define ZYNQMP_DMA_IRQ_SRC_ACCT_ERR	BIT(4)
58 #define ZYNQMP_DMA_BYTE_CNT_OVRFL	BIT(3)
59 #define ZYNQMP_DMA_DST_DSCR_DONE	BIT(2)
60 #define ZYNQMP_DMA_INV_APB		BIT(0)
61 
62 /* Control 0 register bit field definitions */
63 #define ZYNQMP_DMA_OVR_FETCH		BIT(7)
64 #define ZYNQMP_DMA_POINT_TYPE_SG	BIT(6)
65 #define ZYNQMP_DMA_RATE_CTRL_EN		BIT(3)
66 
67 /* Control 1 register bit field definitions */
68 #define ZYNQMP_DMA_SRC_ISSUE		GENMASK(4, 0)
69 
70 /* Data Attribute register bit field definitions */
71 #define ZYNQMP_DMA_ARBURST		GENMASK(27, 26)
72 #define ZYNQMP_DMA_ARCACHE		GENMASK(25, 22)
73 #define ZYNQMP_DMA_ARCACHE_OFST		22
74 #define ZYNQMP_DMA_ARQOS		GENMASK(21, 18)
75 #define ZYNQMP_DMA_ARQOS_OFST		18
76 #define ZYNQMP_DMA_ARLEN		GENMASK(17, 14)
77 #define ZYNQMP_DMA_ARLEN_OFST		14
78 #define ZYNQMP_DMA_AWBURST		GENMASK(13, 12)
79 #define ZYNQMP_DMA_AWCACHE		GENMASK(11, 8)
80 #define ZYNQMP_DMA_AWCACHE_OFST		8
81 #define ZYNQMP_DMA_AWQOS		GENMASK(7, 4)
82 #define ZYNQMP_DMA_AWQOS_OFST		4
83 #define ZYNQMP_DMA_AWLEN		GENMASK(3, 0)
84 #define ZYNQMP_DMA_AWLEN_OFST		0
85 
86 /* Descriptor Attribute register bit field definitions */
87 #define ZYNQMP_DMA_AXCOHRNT		BIT(8)
88 #define ZYNQMP_DMA_AXCACHE		GENMASK(7, 4)
89 #define ZYNQMP_DMA_AXCACHE_OFST		4
90 #define ZYNQMP_DMA_AXQOS		GENMASK(3, 0)
91 #define ZYNQMP_DMA_AXQOS_OFST		0
92 
93 /* Control register 2 bit field definitions */
94 #define ZYNQMP_DMA_ENABLE		BIT(0)
95 
96 /* Buffer Descriptor definitions */
97 #define ZYNQMP_DMA_DESC_CTRL_STOP	0x10
98 #define ZYNQMP_DMA_DESC_CTRL_COMP_INT	0x4
99 #define ZYNQMP_DMA_DESC_CTRL_SIZE_256	0x2
100 #define ZYNQMP_DMA_DESC_CTRL_COHRNT	0x1
101 
102 /* Interrupt Mask specific definitions */
103 #define ZYNQMP_DMA_INT_ERR	(ZYNQMP_DMA_AXI_RD_DATA | \
104 				ZYNQMP_DMA_AXI_WR_DATA | \
105 				ZYNQMP_DMA_AXI_RD_DST_DSCR | \
106 				ZYNQMP_DMA_AXI_RD_SRC_DSCR | \
107 				ZYNQMP_DMA_INV_APB)
108 #define ZYNQMP_DMA_INT_OVRFL	(ZYNQMP_DMA_BYTE_CNT_OVRFL | \
109 				ZYNQMP_DMA_IRQ_SRC_ACCT_ERR | \
110 				ZYNQMP_DMA_IRQ_DST_ACCT_ERR)
111 #define ZYNQMP_DMA_INT_DONE	(ZYNQMP_DMA_DONE | ZYNQMP_DMA_DST_DSCR_DONE)
112 #define ZYNQMP_DMA_INT_EN_DEFAULT_MASK	(ZYNQMP_DMA_INT_DONE | \
113 					ZYNQMP_DMA_INT_ERR | \
114 					ZYNQMP_DMA_INT_OVRFL | \
115 					ZYNQMP_DMA_DST_DSCR_DONE)
116 
117 /* Max number of descriptors per channel */
118 #define ZYNQMP_DMA_NUM_DESCS	32
119 
120 /* Max transfer size per descriptor */
121 #define ZYNQMP_DMA_MAX_TRANS_LEN	0x40000000
122 
123 /* Max burst lengths */
124 #define ZYNQMP_DMA_MAX_DST_BURST_LEN    32768U
125 #define ZYNQMP_DMA_MAX_SRC_BURST_LEN    32768U
126 
127 /* Reset values for data attributes */
128 #define ZYNQMP_DMA_AXCACHE_VAL		0xF
129 
130 #define ZYNQMP_DMA_SRC_ISSUE_RST_VAL	0x1F
131 
132 #define ZYNQMP_DMA_IDS_DEFAULT_MASK	0xFFF
133 
134 /* Bus width in bits */
135 #define ZYNQMP_DMA_BUS_WIDTH_64		64
136 #define ZYNQMP_DMA_BUS_WIDTH_128	128
137 
138 #define ZDMA_PM_TIMEOUT			100
139 
140 #define ZYNQMP_DMA_DESC_SIZE(chan)	(chan->desc_size)
141 
142 #define to_chan(chan)		container_of(chan, struct zynqmp_dma_chan, \
143 					     common)
144 #define tx_to_desc(tx)		container_of(tx, struct zynqmp_dma_desc_sw, \
145 					     async_tx)
146 
147 /**
148  * struct zynqmp_dma_desc_ll - Hw linked list descriptor
149  * @addr: Buffer address
150  * @size: Size of the buffer
151  * @ctrl: Control word
152  * @nxtdscraddr: Next descriptor base address
153  * @rsvd: Reserved field and for Hw internal use.
154  */
155 struct zynqmp_dma_desc_ll {
156 	u64 addr;
157 	u32 size;
158 	u32 ctrl;
159 	u64 nxtdscraddr;
160 	u64 rsvd;
161 };
162 
163 /**
164  * struct zynqmp_dma_desc_sw - Per Transaction structure
165  * @src: Source address for simple mode dma
166  * @dst: Destination address for simple mode dma
167  * @len: Transfer length for simple mode dma
168  * @node: Node in the channel descriptor list
169  * @tx_list: List head for the current transfer
170  * @async_tx: Async transaction descriptor
171  * @src_v: Virtual address of the src descriptor
172  * @src_p: Physical address of the src descriptor
173  * @dst_v: Virtual address of the dst descriptor
174  * @dst_p: Physical address of the dst descriptor
175  */
176 struct zynqmp_dma_desc_sw {
177 	u64 src;
178 	u64 dst;
179 	u32 len;
180 	struct list_head node;
181 	struct list_head tx_list;
182 	struct dma_async_tx_descriptor async_tx;
183 	struct zynqmp_dma_desc_ll *src_v;
184 	dma_addr_t src_p;
185 	struct zynqmp_dma_desc_ll *dst_v;
186 	dma_addr_t dst_p;
187 };
188 
189 /**
190  * struct zynqmp_dma_chan - Driver specific DMA channel structure
191  * @zdev: Driver specific device structure
192  * @regs: Control registers offset
193  * @lock: Descriptor operation lock
194  * @pending_list: Descriptors waiting
195  * @free_list: Descriptors free
196  * @active_list: Descriptors active
197  * @sw_desc_pool: SW descriptor pool
198  * @done_list: Complete descriptors
199  * @common: DMA common channel
200  * @desc_pool_v: Statically allocated descriptor base
201  * @desc_pool_p: Physical allocated descriptor base
202  * @desc_free_cnt: Descriptor available count
203  * @dev: The dma device
204  * @irq: Channel IRQ
205  * @is_dmacoherent: Tells whether dma operations are coherent or not
206  * @tasklet: Cleanup work after irq
207  * @idle : Channel status;
208  * @desc_size: Size of the low level descriptor
209  * @err: Channel has errors
210  * @bus_width: Bus width
211  * @src_burst_len: Source burst length
212  * @dst_burst_len: Dest burst length
213  */
214 struct zynqmp_dma_chan {
215 	struct zynqmp_dma_device *zdev;
216 	void __iomem *regs;
217 	spinlock_t lock;
218 	struct list_head pending_list;
219 	struct list_head free_list;
220 	struct list_head active_list;
221 	struct zynqmp_dma_desc_sw *sw_desc_pool;
222 	struct list_head done_list;
223 	struct dma_chan common;
224 	void *desc_pool_v;
225 	dma_addr_t desc_pool_p;
226 	u32 desc_free_cnt;
227 	struct device *dev;
228 	int irq;
229 	bool is_dmacoherent;
230 	struct tasklet_struct tasklet;
231 	bool idle;
232 	size_t desc_size;
233 	bool err;
234 	u32 bus_width;
235 	u32 src_burst_len;
236 	u32 dst_burst_len;
237 };
238 
239 /**
240  * struct zynqmp_dma_device - DMA device structure
241  * @dev: Device Structure
242  * @common: DMA device structure
243  * @chan: Driver specific DMA channel
244  * @clk_main: Pointer to main clock
245  * @clk_apb: Pointer to apb clock
246  */
247 struct zynqmp_dma_device {
248 	struct device *dev;
249 	struct dma_device common;
250 	struct zynqmp_dma_chan *chan;
251 	struct clk *clk_main;
252 	struct clk *clk_apb;
253 };
254 
255 static inline void zynqmp_dma_writeq(struct zynqmp_dma_chan *chan, u32 reg,
256 				     u64 value)
257 {
258 	lo_hi_writeq(value, chan->regs + reg);
259 }
260 
261 /**
262  * zynqmp_dma_update_desc_to_ctrlr - Updates descriptor to the controller
263  * @chan: ZynqMP DMA DMA channel pointer
264  * @desc: Transaction descriptor pointer
265  */
266 static void zynqmp_dma_update_desc_to_ctrlr(struct zynqmp_dma_chan *chan,
267 				      struct zynqmp_dma_desc_sw *desc)
268 {
269 	dma_addr_t addr;
270 
271 	addr = desc->src_p;
272 	zynqmp_dma_writeq(chan, ZYNQMP_DMA_SRC_START_LSB, addr);
273 	addr = desc->dst_p;
274 	zynqmp_dma_writeq(chan, ZYNQMP_DMA_DST_START_LSB, addr);
275 }
276 
277 /**
278  * zynqmp_dma_desc_config_eod - Mark the descriptor as end descriptor
279  * @chan: ZynqMP DMA channel pointer
280  * @desc: Hw descriptor pointer
281  */
282 static void zynqmp_dma_desc_config_eod(struct zynqmp_dma_chan *chan,
283 				       void *desc)
284 {
285 	struct zynqmp_dma_desc_ll *hw = (struct zynqmp_dma_desc_ll *)desc;
286 
287 	hw->ctrl |= ZYNQMP_DMA_DESC_CTRL_STOP;
288 	hw++;
289 	hw->ctrl |= ZYNQMP_DMA_DESC_CTRL_COMP_INT | ZYNQMP_DMA_DESC_CTRL_STOP;
290 }
291 
292 /**
293  * zynqmp_dma_config_sg_ll_desc - Configure the linked list descriptor
294  * @chan: ZynqMP DMA channel pointer
295  * @sdesc: Hw descriptor pointer
296  * @src: Source buffer address
297  * @dst: Destination buffer address
298  * @len: Transfer length
299  * @prev: Previous hw descriptor pointer
300  */
301 static void zynqmp_dma_config_sg_ll_desc(struct zynqmp_dma_chan *chan,
302 				   struct zynqmp_dma_desc_ll *sdesc,
303 				   dma_addr_t src, dma_addr_t dst, size_t len,
304 				   struct zynqmp_dma_desc_ll *prev)
305 {
306 	struct zynqmp_dma_desc_ll *ddesc = sdesc + 1;
307 
308 	sdesc->size = ddesc->size = len;
309 	sdesc->addr = src;
310 	ddesc->addr = dst;
311 
312 	sdesc->ctrl = ddesc->ctrl = ZYNQMP_DMA_DESC_CTRL_SIZE_256;
313 	if (chan->is_dmacoherent) {
314 		sdesc->ctrl |= ZYNQMP_DMA_DESC_CTRL_COHRNT;
315 		ddesc->ctrl |= ZYNQMP_DMA_DESC_CTRL_COHRNT;
316 	}
317 
318 	if (prev) {
319 		dma_addr_t addr = chan->desc_pool_p +
320 			    ((uintptr_t)sdesc - (uintptr_t)chan->desc_pool_v);
321 		ddesc = prev + 1;
322 		prev->nxtdscraddr = addr;
323 		ddesc->nxtdscraddr = addr + ZYNQMP_DMA_DESC_SIZE(chan);
324 	}
325 }
326 
327 /**
328  * zynqmp_dma_init - Initialize the channel
329  * @chan: ZynqMP DMA channel pointer
330  */
331 static void zynqmp_dma_init(struct zynqmp_dma_chan *chan)
332 {
333 	u32 val;
334 
335 	writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
336 	val = readl(chan->regs + ZYNQMP_DMA_ISR);
337 	writel(val, chan->regs + ZYNQMP_DMA_ISR);
338 
339 	if (chan->is_dmacoherent) {
340 		val = ZYNQMP_DMA_AXCOHRNT;
341 		val = (val & ~ZYNQMP_DMA_AXCACHE) |
342 			(ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_AXCACHE_OFST);
343 		writel(val, chan->regs + ZYNQMP_DMA_DSCR_ATTR);
344 	}
345 
346 	val = readl(chan->regs + ZYNQMP_DMA_DATA_ATTR);
347 	if (chan->is_dmacoherent) {
348 		val = (val & ~ZYNQMP_DMA_ARCACHE) |
349 			(ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_ARCACHE_OFST);
350 		val = (val & ~ZYNQMP_DMA_AWCACHE) |
351 			(ZYNQMP_DMA_AXCACHE_VAL << ZYNQMP_DMA_AWCACHE_OFST);
352 	}
353 	writel(val, chan->regs + ZYNQMP_DMA_DATA_ATTR);
354 
355 	/* Clearing the interrupt account rgisters */
356 	val = readl(chan->regs + ZYNQMP_DMA_IRQ_SRC_ACCT);
357 	val = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
358 
359 	chan->idle = true;
360 }
361 
362 /**
363  * zynqmp_dma_tx_submit - Submit DMA transaction
364  * @tx: Async transaction descriptor pointer
365  *
366  * Return: cookie value
367  */
368 static dma_cookie_t zynqmp_dma_tx_submit(struct dma_async_tx_descriptor *tx)
369 {
370 	struct zynqmp_dma_chan *chan = to_chan(tx->chan);
371 	struct zynqmp_dma_desc_sw *desc, *new;
372 	dma_cookie_t cookie;
373 	unsigned long irqflags;
374 
375 	new = tx_to_desc(tx);
376 	spin_lock_irqsave(&chan->lock, irqflags);
377 	cookie = dma_cookie_assign(tx);
378 
379 	if (!list_empty(&chan->pending_list)) {
380 		desc = list_last_entry(&chan->pending_list,
381 				     struct zynqmp_dma_desc_sw, node);
382 		if (!list_empty(&desc->tx_list))
383 			desc = list_last_entry(&desc->tx_list,
384 					       struct zynqmp_dma_desc_sw, node);
385 		desc->src_v->nxtdscraddr = new->src_p;
386 		desc->src_v->ctrl &= ~ZYNQMP_DMA_DESC_CTRL_STOP;
387 		desc->dst_v->nxtdscraddr = new->dst_p;
388 		desc->dst_v->ctrl &= ~ZYNQMP_DMA_DESC_CTRL_STOP;
389 	}
390 
391 	list_add_tail(&new->node, &chan->pending_list);
392 	spin_unlock_irqrestore(&chan->lock, irqflags);
393 
394 	return cookie;
395 }
396 
397 /**
398  * zynqmp_dma_get_descriptor - Get the sw descriptor from the pool
399  * @chan: ZynqMP DMA channel pointer
400  *
401  * Return: The sw descriptor
402  */
403 static struct zynqmp_dma_desc_sw *
404 zynqmp_dma_get_descriptor(struct zynqmp_dma_chan *chan)
405 {
406 	struct zynqmp_dma_desc_sw *desc;
407 	unsigned long irqflags;
408 
409 	spin_lock_irqsave(&chan->lock, irqflags);
410 	desc = list_first_entry(&chan->free_list,
411 				struct zynqmp_dma_desc_sw, node);
412 	list_del(&desc->node);
413 	spin_unlock_irqrestore(&chan->lock, irqflags);
414 
415 	INIT_LIST_HEAD(&desc->tx_list);
416 	/* Clear the src and dst descriptor memory */
417 	memset((void *)desc->src_v, 0, ZYNQMP_DMA_DESC_SIZE(chan));
418 	memset((void *)desc->dst_v, 0, ZYNQMP_DMA_DESC_SIZE(chan));
419 
420 	return desc;
421 }
422 
423 /**
424  * zynqmp_dma_free_descriptor - Issue pending transactions
425  * @chan: ZynqMP DMA channel pointer
426  * @sdesc: Transaction descriptor pointer
427  */
428 static void zynqmp_dma_free_descriptor(struct zynqmp_dma_chan *chan,
429 				 struct zynqmp_dma_desc_sw *sdesc)
430 {
431 	struct zynqmp_dma_desc_sw *child, *next;
432 
433 	chan->desc_free_cnt++;
434 	list_move_tail(&sdesc->node, &chan->free_list);
435 	list_for_each_entry_safe(child, next, &sdesc->tx_list, node) {
436 		chan->desc_free_cnt++;
437 		list_move_tail(&child->node, &chan->free_list);
438 	}
439 }
440 
441 /**
442  * zynqmp_dma_free_desc_list - Free descriptors list
443  * @chan: ZynqMP DMA channel pointer
444  * @list: List to parse and delete the descriptor
445  */
446 static void zynqmp_dma_free_desc_list(struct zynqmp_dma_chan *chan,
447 				      struct list_head *list)
448 {
449 	struct zynqmp_dma_desc_sw *desc, *next;
450 
451 	list_for_each_entry_safe(desc, next, list, node)
452 		zynqmp_dma_free_descriptor(chan, desc);
453 }
454 
455 /**
456  * zynqmp_dma_alloc_chan_resources - Allocate channel resources
457  * @dchan: DMA channel
458  *
459  * Return: Number of descriptors on success and failure value on error
460  */
461 static int zynqmp_dma_alloc_chan_resources(struct dma_chan *dchan)
462 {
463 	struct zynqmp_dma_chan *chan = to_chan(dchan);
464 	struct zynqmp_dma_desc_sw *desc;
465 	int i, ret;
466 
467 	ret = pm_runtime_resume_and_get(chan->dev);
468 	if (ret < 0)
469 		return ret;
470 
471 	chan->sw_desc_pool = kcalloc(ZYNQMP_DMA_NUM_DESCS, sizeof(*desc),
472 				     GFP_KERNEL);
473 	if (!chan->sw_desc_pool)
474 		return -ENOMEM;
475 
476 	chan->idle = true;
477 	chan->desc_free_cnt = ZYNQMP_DMA_NUM_DESCS;
478 
479 	INIT_LIST_HEAD(&chan->free_list);
480 
481 	for (i = 0; i < ZYNQMP_DMA_NUM_DESCS; i++) {
482 		desc = chan->sw_desc_pool + i;
483 		dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
484 		desc->async_tx.tx_submit = zynqmp_dma_tx_submit;
485 		list_add_tail(&desc->node, &chan->free_list);
486 	}
487 
488 	chan->desc_pool_v = dma_alloc_coherent(chan->dev,
489 					       (2 * ZYNQMP_DMA_DESC_SIZE(chan) *
490 					       ZYNQMP_DMA_NUM_DESCS),
491 					       &chan->desc_pool_p, GFP_KERNEL);
492 	if (!chan->desc_pool_v)
493 		return -ENOMEM;
494 
495 	for (i = 0; i < ZYNQMP_DMA_NUM_DESCS; i++) {
496 		desc = chan->sw_desc_pool + i;
497 		desc->src_v = (struct zynqmp_dma_desc_ll *) (chan->desc_pool_v +
498 					(i * ZYNQMP_DMA_DESC_SIZE(chan) * 2));
499 		desc->dst_v = (struct zynqmp_dma_desc_ll *) (desc->src_v + 1);
500 		desc->src_p = chan->desc_pool_p +
501 				(i * ZYNQMP_DMA_DESC_SIZE(chan) * 2);
502 		desc->dst_p = desc->src_p + ZYNQMP_DMA_DESC_SIZE(chan);
503 	}
504 
505 	return ZYNQMP_DMA_NUM_DESCS;
506 }
507 
508 /**
509  * zynqmp_dma_start - Start DMA channel
510  * @chan: ZynqMP DMA channel pointer
511  */
512 static void zynqmp_dma_start(struct zynqmp_dma_chan *chan)
513 {
514 	writel(ZYNQMP_DMA_INT_EN_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IER);
515 	writel(0, chan->regs + ZYNQMP_DMA_TOTAL_BYTE);
516 	chan->idle = false;
517 	writel(ZYNQMP_DMA_ENABLE, chan->regs + ZYNQMP_DMA_CTRL2);
518 }
519 
520 /**
521  * zynqmp_dma_handle_ovfl_int - Process the overflow interrupt
522  * @chan: ZynqMP DMA channel pointer
523  * @status: Interrupt status value
524  */
525 static void zynqmp_dma_handle_ovfl_int(struct zynqmp_dma_chan *chan, u32 status)
526 {
527 	if (status & ZYNQMP_DMA_BYTE_CNT_OVRFL)
528 		writel(0, chan->regs + ZYNQMP_DMA_TOTAL_BYTE);
529 	if (status & ZYNQMP_DMA_IRQ_DST_ACCT_ERR)
530 		readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
531 	if (status & ZYNQMP_DMA_IRQ_SRC_ACCT_ERR)
532 		readl(chan->regs + ZYNQMP_DMA_IRQ_SRC_ACCT);
533 }
534 
535 static void zynqmp_dma_config(struct zynqmp_dma_chan *chan)
536 {
537 	u32 val, burst_val;
538 
539 	val = readl(chan->regs + ZYNQMP_DMA_CTRL0);
540 	val |= ZYNQMP_DMA_POINT_TYPE_SG;
541 	writel(val, chan->regs + ZYNQMP_DMA_CTRL0);
542 
543 	val = readl(chan->regs + ZYNQMP_DMA_DATA_ATTR);
544 	burst_val = __ilog2_u32(chan->src_burst_len);
545 	val = (val & ~ZYNQMP_DMA_ARLEN) |
546 		((burst_val << ZYNQMP_DMA_ARLEN_OFST) & ZYNQMP_DMA_ARLEN);
547 	burst_val = __ilog2_u32(chan->dst_burst_len);
548 	val = (val & ~ZYNQMP_DMA_AWLEN) |
549 		((burst_val << ZYNQMP_DMA_AWLEN_OFST) & ZYNQMP_DMA_AWLEN);
550 	writel(val, chan->regs + ZYNQMP_DMA_DATA_ATTR);
551 }
552 
553 /**
554  * zynqmp_dma_device_config - Zynqmp dma device configuration
555  * @dchan: DMA channel
556  * @config: DMA device config
557  *
558  * Return: 0 always
559  */
560 static int zynqmp_dma_device_config(struct dma_chan *dchan,
561 				    struct dma_slave_config *config)
562 {
563 	struct zynqmp_dma_chan *chan = to_chan(dchan);
564 
565 	chan->src_burst_len = clamp(config->src_maxburst, 1U,
566 		ZYNQMP_DMA_MAX_SRC_BURST_LEN);
567 	chan->dst_burst_len = clamp(config->dst_maxburst, 1U,
568 		ZYNQMP_DMA_MAX_DST_BURST_LEN);
569 
570 	return 0;
571 }
572 
573 /**
574  * zynqmp_dma_start_transfer - Initiate the new transfer
575  * @chan: ZynqMP DMA channel pointer
576  */
577 static void zynqmp_dma_start_transfer(struct zynqmp_dma_chan *chan)
578 {
579 	struct zynqmp_dma_desc_sw *desc;
580 
581 	if (!chan->idle)
582 		return;
583 
584 	zynqmp_dma_config(chan);
585 
586 	desc = list_first_entry_or_null(&chan->pending_list,
587 					struct zynqmp_dma_desc_sw, node);
588 	if (!desc)
589 		return;
590 
591 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
592 	zynqmp_dma_update_desc_to_ctrlr(chan, desc);
593 	zynqmp_dma_start(chan);
594 }
595 
596 
597 /**
598  * zynqmp_dma_chan_desc_cleanup - Cleanup the completed descriptors
599  * @chan: ZynqMP DMA channel
600  */
601 static void zynqmp_dma_chan_desc_cleanup(struct zynqmp_dma_chan *chan)
602 {
603 	struct zynqmp_dma_desc_sw *desc, *next;
604 	unsigned long irqflags;
605 
606 	spin_lock_irqsave(&chan->lock, irqflags);
607 
608 	list_for_each_entry_safe(desc, next, &chan->done_list, node) {
609 		struct dmaengine_desc_callback cb;
610 
611 		dmaengine_desc_get_callback(&desc->async_tx, &cb);
612 		if (dmaengine_desc_callback_valid(&cb)) {
613 			spin_unlock_irqrestore(&chan->lock, irqflags);
614 			dmaengine_desc_callback_invoke(&cb, NULL);
615 			spin_lock_irqsave(&chan->lock, irqflags);
616 		}
617 
618 		/* Run any dependencies, then free the descriptor */
619 		zynqmp_dma_free_descriptor(chan, desc);
620 	}
621 
622 	spin_unlock_irqrestore(&chan->lock, irqflags);
623 }
624 
625 /**
626  * zynqmp_dma_complete_descriptor - Mark the active descriptor as complete
627  * @chan: ZynqMP DMA channel pointer
628  */
629 static void zynqmp_dma_complete_descriptor(struct zynqmp_dma_chan *chan)
630 {
631 	struct zynqmp_dma_desc_sw *desc;
632 
633 	desc = list_first_entry_or_null(&chan->active_list,
634 					struct zynqmp_dma_desc_sw, node);
635 	if (!desc)
636 		return;
637 	list_del(&desc->node);
638 	dma_cookie_complete(&desc->async_tx);
639 	list_add_tail(&desc->node, &chan->done_list);
640 }
641 
642 /**
643  * zynqmp_dma_issue_pending - Issue pending transactions
644  * @dchan: DMA channel pointer
645  */
646 static void zynqmp_dma_issue_pending(struct dma_chan *dchan)
647 {
648 	struct zynqmp_dma_chan *chan = to_chan(dchan);
649 	unsigned long irqflags;
650 
651 	spin_lock_irqsave(&chan->lock, irqflags);
652 	zynqmp_dma_start_transfer(chan);
653 	spin_unlock_irqrestore(&chan->lock, irqflags);
654 }
655 
656 /**
657  * zynqmp_dma_free_descriptors - Free channel descriptors
658  * @chan: ZynqMP DMA channel pointer
659  */
660 static void zynqmp_dma_free_descriptors(struct zynqmp_dma_chan *chan)
661 {
662 	unsigned long irqflags;
663 
664 	spin_lock_irqsave(&chan->lock, irqflags);
665 	zynqmp_dma_free_desc_list(chan, &chan->active_list);
666 	zynqmp_dma_free_desc_list(chan, &chan->pending_list);
667 	zynqmp_dma_free_desc_list(chan, &chan->done_list);
668 	spin_unlock_irqrestore(&chan->lock, irqflags);
669 }
670 
671 /**
672  * zynqmp_dma_free_chan_resources - Free channel resources
673  * @dchan: DMA channel pointer
674  */
675 static void zynqmp_dma_free_chan_resources(struct dma_chan *dchan)
676 {
677 	struct zynqmp_dma_chan *chan = to_chan(dchan);
678 
679 	zynqmp_dma_free_descriptors(chan);
680 	dma_free_coherent(chan->dev,
681 		(2 * ZYNQMP_DMA_DESC_SIZE(chan) * ZYNQMP_DMA_NUM_DESCS),
682 		chan->desc_pool_v, chan->desc_pool_p);
683 	kfree(chan->sw_desc_pool);
684 	pm_runtime_mark_last_busy(chan->dev);
685 	pm_runtime_put_autosuspend(chan->dev);
686 }
687 
688 /**
689  * zynqmp_dma_reset - Reset the channel
690  * @chan: ZynqMP DMA channel pointer
691  */
692 static void zynqmp_dma_reset(struct zynqmp_dma_chan *chan)
693 {
694 	unsigned long irqflags;
695 
696 	writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
697 
698 	spin_lock_irqsave(&chan->lock, irqflags);
699 	zynqmp_dma_complete_descriptor(chan);
700 	spin_unlock_irqrestore(&chan->lock, irqflags);
701 	zynqmp_dma_chan_desc_cleanup(chan);
702 	zynqmp_dma_free_descriptors(chan);
703 
704 	zynqmp_dma_init(chan);
705 }
706 
707 /**
708  * zynqmp_dma_irq_handler - ZynqMP DMA Interrupt handler
709  * @irq: IRQ number
710  * @data: Pointer to the ZynqMP DMA channel structure
711  *
712  * Return: IRQ_HANDLED/IRQ_NONE
713  */
714 static irqreturn_t zynqmp_dma_irq_handler(int irq, void *data)
715 {
716 	struct zynqmp_dma_chan *chan = (struct zynqmp_dma_chan *)data;
717 	u32 isr, imr, status;
718 	irqreturn_t ret = IRQ_NONE;
719 
720 	isr = readl(chan->regs + ZYNQMP_DMA_ISR);
721 	imr = readl(chan->regs + ZYNQMP_DMA_IMR);
722 	status = isr & ~imr;
723 
724 	writel(isr, chan->regs + ZYNQMP_DMA_ISR);
725 	if (status & ZYNQMP_DMA_INT_DONE) {
726 		tasklet_schedule(&chan->tasklet);
727 		ret = IRQ_HANDLED;
728 	}
729 
730 	if (status & ZYNQMP_DMA_DONE)
731 		chan->idle = true;
732 
733 	if (status & ZYNQMP_DMA_INT_ERR) {
734 		chan->err = true;
735 		tasklet_schedule(&chan->tasklet);
736 		dev_err(chan->dev, "Channel %p has errors\n", chan);
737 		ret = IRQ_HANDLED;
738 	}
739 
740 	if (status & ZYNQMP_DMA_INT_OVRFL) {
741 		zynqmp_dma_handle_ovfl_int(chan, status);
742 		dev_dbg(chan->dev, "Channel %p overflow interrupt\n", chan);
743 		ret = IRQ_HANDLED;
744 	}
745 
746 	return ret;
747 }
748 
749 /**
750  * zynqmp_dma_do_tasklet - Schedule completion tasklet
751  * @t: Pointer to the ZynqMP DMA channel structure
752  */
753 static void zynqmp_dma_do_tasklet(struct tasklet_struct *t)
754 {
755 	struct zynqmp_dma_chan *chan = from_tasklet(chan, t, tasklet);
756 	u32 count;
757 	unsigned long irqflags;
758 
759 	if (chan->err) {
760 		zynqmp_dma_reset(chan);
761 		chan->err = false;
762 		return;
763 	}
764 
765 	spin_lock_irqsave(&chan->lock, irqflags);
766 	count = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT);
767 	while (count) {
768 		zynqmp_dma_complete_descriptor(chan);
769 		count--;
770 	}
771 	spin_unlock_irqrestore(&chan->lock, irqflags);
772 
773 	zynqmp_dma_chan_desc_cleanup(chan);
774 
775 	if (chan->idle) {
776 		spin_lock_irqsave(&chan->lock, irqflags);
777 		zynqmp_dma_start_transfer(chan);
778 		spin_unlock_irqrestore(&chan->lock, irqflags);
779 	}
780 }
781 
782 /**
783  * zynqmp_dma_device_terminate_all - Aborts all transfers on a channel
784  * @dchan: DMA channel pointer
785  *
786  * Return: Always '0'
787  */
788 static int zynqmp_dma_device_terminate_all(struct dma_chan *dchan)
789 {
790 	struct zynqmp_dma_chan *chan = to_chan(dchan);
791 
792 	writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS);
793 	zynqmp_dma_free_descriptors(chan);
794 
795 	return 0;
796 }
797 
798 /**
799  * zynqmp_dma_prep_memcpy - prepare descriptors for memcpy transaction
800  * @dchan: DMA channel
801  * @dma_dst: Destination buffer address
802  * @dma_src: Source buffer address
803  * @len: Transfer length
804  * @flags: transfer ack flags
805  *
806  * Return: Async transaction descriptor on success and NULL on failure
807  */
808 static struct dma_async_tx_descriptor *zynqmp_dma_prep_memcpy(
809 				struct dma_chan *dchan, dma_addr_t dma_dst,
810 				dma_addr_t dma_src, size_t len, ulong flags)
811 {
812 	struct zynqmp_dma_chan *chan;
813 	struct zynqmp_dma_desc_sw *new, *first = NULL;
814 	void *desc = NULL, *prev = NULL;
815 	size_t copy;
816 	u32 desc_cnt;
817 	unsigned long irqflags;
818 
819 	chan = to_chan(dchan);
820 
821 	desc_cnt = DIV_ROUND_UP(len, ZYNQMP_DMA_MAX_TRANS_LEN);
822 
823 	spin_lock_irqsave(&chan->lock, irqflags);
824 	if (desc_cnt > chan->desc_free_cnt) {
825 		spin_unlock_irqrestore(&chan->lock, irqflags);
826 		dev_dbg(chan->dev, "chan %p descs are not available\n", chan);
827 		return NULL;
828 	}
829 	chan->desc_free_cnt = chan->desc_free_cnt - desc_cnt;
830 	spin_unlock_irqrestore(&chan->lock, irqflags);
831 
832 	do {
833 		/* Allocate and populate the descriptor */
834 		new = zynqmp_dma_get_descriptor(chan);
835 
836 		copy = min_t(size_t, len, ZYNQMP_DMA_MAX_TRANS_LEN);
837 		desc = (struct zynqmp_dma_desc_ll *)new->src_v;
838 		zynqmp_dma_config_sg_ll_desc(chan, desc, dma_src,
839 					     dma_dst, copy, prev);
840 		prev = desc;
841 		len -= copy;
842 		dma_src += copy;
843 		dma_dst += copy;
844 		if (!first)
845 			first = new;
846 		else
847 			list_add_tail(&new->node, &first->tx_list);
848 	} while (len);
849 
850 	zynqmp_dma_desc_config_eod(chan, desc);
851 	async_tx_ack(&first->async_tx);
852 	first->async_tx.flags = flags;
853 	return &first->async_tx;
854 }
855 
856 /**
857  * zynqmp_dma_chan_remove - Channel remove function
858  * @chan: ZynqMP DMA channel pointer
859  */
860 static void zynqmp_dma_chan_remove(struct zynqmp_dma_chan *chan)
861 {
862 	if (!chan)
863 		return;
864 
865 	if (chan->irq)
866 		devm_free_irq(chan->zdev->dev, chan->irq, chan);
867 	tasklet_kill(&chan->tasklet);
868 	list_del(&chan->common.device_node);
869 }
870 
871 /**
872  * zynqmp_dma_chan_probe - Per Channel Probing
873  * @zdev: Driver specific device structure
874  * @pdev: Pointer to the platform_device structure
875  *
876  * Return: '0' on success and failure value on error
877  */
878 static int zynqmp_dma_chan_probe(struct zynqmp_dma_device *zdev,
879 			   struct platform_device *pdev)
880 {
881 	struct zynqmp_dma_chan *chan;
882 	struct resource *res;
883 	struct device_node *node = pdev->dev.of_node;
884 	int err;
885 
886 	chan = devm_kzalloc(zdev->dev, sizeof(*chan), GFP_KERNEL);
887 	if (!chan)
888 		return -ENOMEM;
889 	chan->dev = zdev->dev;
890 	chan->zdev = zdev;
891 
892 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
893 	chan->regs = devm_ioremap_resource(&pdev->dev, res);
894 	if (IS_ERR(chan->regs))
895 		return PTR_ERR(chan->regs);
896 
897 	chan->bus_width = ZYNQMP_DMA_BUS_WIDTH_64;
898 	chan->dst_burst_len = ZYNQMP_DMA_MAX_DST_BURST_LEN;
899 	chan->src_burst_len = ZYNQMP_DMA_MAX_SRC_BURST_LEN;
900 	err = of_property_read_u32(node, "xlnx,bus-width", &chan->bus_width);
901 	if (err < 0) {
902 		dev_err(&pdev->dev, "missing xlnx,bus-width property\n");
903 		return err;
904 	}
905 
906 	if (chan->bus_width != ZYNQMP_DMA_BUS_WIDTH_64 &&
907 	    chan->bus_width != ZYNQMP_DMA_BUS_WIDTH_128) {
908 		dev_err(zdev->dev, "invalid bus-width value");
909 		return -EINVAL;
910 	}
911 
912 	chan->is_dmacoherent =  of_property_read_bool(node, "dma-coherent");
913 	zdev->chan = chan;
914 	tasklet_setup(&chan->tasklet, zynqmp_dma_do_tasklet);
915 	spin_lock_init(&chan->lock);
916 	INIT_LIST_HEAD(&chan->active_list);
917 	INIT_LIST_HEAD(&chan->pending_list);
918 	INIT_LIST_HEAD(&chan->done_list);
919 	INIT_LIST_HEAD(&chan->free_list);
920 
921 	dma_cookie_init(&chan->common);
922 	chan->common.device = &zdev->common;
923 	list_add_tail(&chan->common.device_node, &zdev->common.channels);
924 
925 	zynqmp_dma_init(chan);
926 	chan->irq = platform_get_irq(pdev, 0);
927 	if (chan->irq < 0)
928 		return -ENXIO;
929 	err = devm_request_irq(&pdev->dev, chan->irq, zynqmp_dma_irq_handler, 0,
930 			       "zynqmp-dma", chan);
931 	if (err)
932 		return err;
933 
934 	chan->desc_size = sizeof(struct zynqmp_dma_desc_ll);
935 	chan->idle = true;
936 	return 0;
937 }
938 
939 /**
940  * of_zynqmp_dma_xlate - Translation function
941  * @dma_spec: Pointer to DMA specifier as found in the device tree
942  * @ofdma: Pointer to DMA controller data
943  *
944  * Return: DMA channel pointer on success and NULL on error
945  */
946 static struct dma_chan *of_zynqmp_dma_xlate(struct of_phandle_args *dma_spec,
947 					    struct of_dma *ofdma)
948 {
949 	struct zynqmp_dma_device *zdev = ofdma->of_dma_data;
950 
951 	return dma_get_slave_channel(&zdev->chan->common);
952 }
953 
954 /**
955  * zynqmp_dma_suspend - Suspend method for the driver
956  * @dev:	Address of the device structure
957  *
958  * Put the driver into low power mode.
959  * Return: 0 on success and failure value on error
960  */
961 static int __maybe_unused zynqmp_dma_suspend(struct device *dev)
962 {
963 	if (!device_may_wakeup(dev))
964 		return pm_runtime_force_suspend(dev);
965 
966 	return 0;
967 }
968 
969 /**
970  * zynqmp_dma_resume - Resume from suspend
971  * @dev:	Address of the device structure
972  *
973  * Resume operation after suspend.
974  * Return: 0 on success and failure value on error
975  */
976 static int __maybe_unused zynqmp_dma_resume(struct device *dev)
977 {
978 	if (!device_may_wakeup(dev))
979 		return pm_runtime_force_resume(dev);
980 
981 	return 0;
982 }
983 
984 /**
985  * zynqmp_dma_runtime_suspend - Runtime suspend method for the driver
986  * @dev:	Address of the device structure
987  *
988  * Put the driver into low power mode.
989  * Return: 0 always
990  */
991 static int __maybe_unused zynqmp_dma_runtime_suspend(struct device *dev)
992 {
993 	struct zynqmp_dma_device *zdev = dev_get_drvdata(dev);
994 
995 	clk_disable_unprepare(zdev->clk_main);
996 	clk_disable_unprepare(zdev->clk_apb);
997 
998 	return 0;
999 }
1000 
1001 /**
1002  * zynqmp_dma_runtime_resume - Runtime suspend method for the driver
1003  * @dev:	Address of the device structure
1004  *
1005  * Put the driver into low power mode.
1006  * Return: 0 always
1007  */
1008 static int __maybe_unused zynqmp_dma_runtime_resume(struct device *dev)
1009 {
1010 	struct zynqmp_dma_device *zdev = dev_get_drvdata(dev);
1011 	int err;
1012 
1013 	err = clk_prepare_enable(zdev->clk_main);
1014 	if (err) {
1015 		dev_err(dev, "Unable to enable main clock.\n");
1016 		return err;
1017 	}
1018 
1019 	err = clk_prepare_enable(zdev->clk_apb);
1020 	if (err) {
1021 		dev_err(dev, "Unable to enable apb clock.\n");
1022 		clk_disable_unprepare(zdev->clk_main);
1023 		return err;
1024 	}
1025 
1026 	return 0;
1027 }
1028 
1029 static const struct dev_pm_ops zynqmp_dma_dev_pm_ops = {
1030 	SET_SYSTEM_SLEEP_PM_OPS(zynqmp_dma_suspend, zynqmp_dma_resume)
1031 	SET_RUNTIME_PM_OPS(zynqmp_dma_runtime_suspend,
1032 			   zynqmp_dma_runtime_resume, NULL)
1033 };
1034 
1035 /**
1036  * zynqmp_dma_probe - Driver probe function
1037  * @pdev: Pointer to the platform_device structure
1038  *
1039  * Return: '0' on success and failure value on error
1040  */
1041 static int zynqmp_dma_probe(struct platform_device *pdev)
1042 {
1043 	struct zynqmp_dma_device *zdev;
1044 	struct dma_device *p;
1045 	int ret;
1046 
1047 	zdev = devm_kzalloc(&pdev->dev, sizeof(*zdev), GFP_KERNEL);
1048 	if (!zdev)
1049 		return -ENOMEM;
1050 
1051 	zdev->dev = &pdev->dev;
1052 	INIT_LIST_HEAD(&zdev->common.channels);
1053 
1054 	dma_set_mask(&pdev->dev, DMA_BIT_MASK(44));
1055 	dma_cap_set(DMA_MEMCPY, zdev->common.cap_mask);
1056 
1057 	p = &zdev->common;
1058 	p->device_prep_dma_memcpy = zynqmp_dma_prep_memcpy;
1059 	p->device_terminate_all = zynqmp_dma_device_terminate_all;
1060 	p->device_issue_pending = zynqmp_dma_issue_pending;
1061 	p->device_alloc_chan_resources = zynqmp_dma_alloc_chan_resources;
1062 	p->device_free_chan_resources = zynqmp_dma_free_chan_resources;
1063 	p->device_tx_status = dma_cookie_status;
1064 	p->device_config = zynqmp_dma_device_config;
1065 	p->dev = &pdev->dev;
1066 
1067 	zdev->clk_main = devm_clk_get(&pdev->dev, "clk_main");
1068 	if (IS_ERR(zdev->clk_main))
1069 		return dev_err_probe(&pdev->dev, PTR_ERR(zdev->clk_main),
1070 				     "main clock not found.\n");
1071 
1072 	zdev->clk_apb = devm_clk_get(&pdev->dev, "clk_apb");
1073 	if (IS_ERR(zdev->clk_apb))
1074 		return dev_err_probe(&pdev->dev, PTR_ERR(zdev->clk_apb),
1075 				     "apb clock not found.\n");
1076 
1077 	platform_set_drvdata(pdev, zdev);
1078 	pm_runtime_set_autosuspend_delay(zdev->dev, ZDMA_PM_TIMEOUT);
1079 	pm_runtime_use_autosuspend(zdev->dev);
1080 	pm_runtime_enable(zdev->dev);
1081 	ret = pm_runtime_resume_and_get(zdev->dev);
1082 	if (ret < 0) {
1083 		dev_err(&pdev->dev, "device wakeup failed.\n");
1084 		pm_runtime_disable(zdev->dev);
1085 	}
1086 	if (!pm_runtime_enabled(zdev->dev)) {
1087 		ret = zynqmp_dma_runtime_resume(zdev->dev);
1088 		if (ret)
1089 			return ret;
1090 	}
1091 
1092 	ret = zynqmp_dma_chan_probe(zdev, pdev);
1093 	if (ret) {
1094 		dev_err_probe(&pdev->dev, ret, "Probing channel failed\n");
1095 		goto err_disable_pm;
1096 	}
1097 
1098 	p->dst_addr_widths = BIT(zdev->chan->bus_width / 8);
1099 	p->src_addr_widths = BIT(zdev->chan->bus_width / 8);
1100 
1101 	ret = dma_async_device_register(&zdev->common);
1102 	if (ret) {
1103 		dev_err(zdev->dev, "failed to register the dma device\n");
1104 		goto free_chan_resources;
1105 	}
1106 
1107 	ret = of_dma_controller_register(pdev->dev.of_node,
1108 					 of_zynqmp_dma_xlate, zdev);
1109 	if (ret) {
1110 		dev_err_probe(&pdev->dev, ret, "Unable to register DMA to DT\n");
1111 		dma_async_device_unregister(&zdev->common);
1112 		goto free_chan_resources;
1113 	}
1114 
1115 	pm_runtime_mark_last_busy(zdev->dev);
1116 	pm_runtime_put_sync_autosuspend(zdev->dev);
1117 
1118 	return 0;
1119 
1120 free_chan_resources:
1121 	zynqmp_dma_chan_remove(zdev->chan);
1122 err_disable_pm:
1123 	if (!pm_runtime_enabled(zdev->dev))
1124 		zynqmp_dma_runtime_suspend(zdev->dev);
1125 	pm_runtime_disable(zdev->dev);
1126 	return ret;
1127 }
1128 
1129 /**
1130  * zynqmp_dma_remove - Driver remove function
1131  * @pdev: Pointer to the platform_device structure
1132  *
1133  * Return: Always '0'
1134  */
1135 static int zynqmp_dma_remove(struct platform_device *pdev)
1136 {
1137 	struct zynqmp_dma_device *zdev = platform_get_drvdata(pdev);
1138 
1139 	of_dma_controller_free(pdev->dev.of_node);
1140 	dma_async_device_unregister(&zdev->common);
1141 
1142 	zynqmp_dma_chan_remove(zdev->chan);
1143 	pm_runtime_disable(zdev->dev);
1144 	if (!pm_runtime_enabled(zdev->dev))
1145 		zynqmp_dma_runtime_suspend(zdev->dev);
1146 
1147 	return 0;
1148 }
1149 
1150 static const struct of_device_id zynqmp_dma_of_match[] = {
1151 	{ .compatible = "xlnx,zynqmp-dma-1.0", },
1152 	{}
1153 };
1154 MODULE_DEVICE_TABLE(of, zynqmp_dma_of_match);
1155 
1156 static struct platform_driver zynqmp_dma_driver = {
1157 	.driver = {
1158 		.name = "xilinx-zynqmp-dma",
1159 		.of_match_table = zynqmp_dma_of_match,
1160 		.pm = &zynqmp_dma_dev_pm_ops,
1161 	},
1162 	.probe = zynqmp_dma_probe,
1163 	.remove = zynqmp_dma_remove,
1164 };
1165 
1166 module_platform_driver(zynqmp_dma_driver);
1167 
1168 MODULE_LICENSE("GPL");
1169 MODULE_AUTHOR("Xilinx, Inc.");
1170 MODULE_DESCRIPTION("Xilinx ZynqMP DMA driver");
1171