1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Xilinx ZynqMP DPDMA Engine driver
4  *
5  * Copyright (C) 2015 - 2020 Xilinx, Inc.
6  *
7  * Author: Hyun Woo Kwon <hyun.kwon@xilinx.com>
8  */
9 
10 #include <linux/bitfield.h>
11 #include <linux/bits.h>
12 #include <linux/clk.h>
13 #include <linux/debugfs.h>
14 #include <linux/delay.h>
15 #include <linux/dmaengine.h>
16 #include <linux/dmapool.h>
17 #include <linux/interrupt.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/of_dma.h>
21 #include <linux/platform_device.h>
22 #include <linux/sched.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
25 #include <linux/wait.h>
26 
27 #include <dt-bindings/dma/xlnx-zynqmp-dpdma.h>
28 
29 #include "../dmaengine.h"
30 #include "../virt-dma.h"
31 
32 /* DPDMA registers */
33 #define XILINX_DPDMA_ERR_CTRL				0x000
34 #define XILINX_DPDMA_ISR				0x004
35 #define XILINX_DPDMA_IMR				0x008
36 #define XILINX_DPDMA_IEN				0x00c
37 #define XILINX_DPDMA_IDS				0x010
38 #define XILINX_DPDMA_INTR_DESC_DONE(n)			BIT((n) + 0)
39 #define XILINX_DPDMA_INTR_DESC_DONE_MASK		GENMASK(5, 0)
40 #define XILINX_DPDMA_INTR_NO_OSTAND(n)			BIT((n) + 6)
41 #define XILINX_DPDMA_INTR_NO_OSTAND_MASK		GENMASK(11, 6)
42 #define XILINX_DPDMA_INTR_AXI_ERR(n)			BIT((n) + 12)
43 #define XILINX_DPDMA_INTR_AXI_ERR_MASK			GENMASK(17, 12)
44 #define XILINX_DPDMA_INTR_DESC_ERR(n)			BIT((n) + 16)
45 #define XILINX_DPDMA_INTR_DESC_ERR_MASK			GENMASK(23, 18)
46 #define XILINX_DPDMA_INTR_WR_CMD_FIFO_FULL		BIT(24)
47 #define XILINX_DPDMA_INTR_WR_DATA_FIFO_FULL		BIT(25)
48 #define XILINX_DPDMA_INTR_AXI_4K_CROSS			BIT(26)
49 #define XILINX_DPDMA_INTR_VSYNC				BIT(27)
50 #define XILINX_DPDMA_INTR_CHAN_ERR_MASK			0x00041000
51 #define XILINX_DPDMA_INTR_CHAN_ERR			0x00fff000
52 #define XILINX_DPDMA_INTR_GLOBAL_ERR			0x07000000
53 #define XILINX_DPDMA_INTR_ERR_ALL			0x07fff000
54 #define XILINX_DPDMA_INTR_CHAN_MASK			0x00041041
55 #define XILINX_DPDMA_INTR_GLOBAL_MASK			0x0f000000
56 #define XILINX_DPDMA_INTR_ALL				0x0fffffff
57 #define XILINX_DPDMA_EISR				0x014
58 #define XILINX_DPDMA_EIMR				0x018
59 #define XILINX_DPDMA_EIEN				0x01c
60 #define XILINX_DPDMA_EIDS				0x020
61 #define XILINX_DPDMA_EINTR_INV_APB			BIT(0)
62 #define XILINX_DPDMA_EINTR_RD_AXI_ERR(n)		BIT((n) + 1)
63 #define XILINX_DPDMA_EINTR_RD_AXI_ERR_MASK		GENMASK(6, 1)
64 #define XILINX_DPDMA_EINTR_PRE_ERR(n)			BIT((n) + 7)
65 #define XILINX_DPDMA_EINTR_PRE_ERR_MASK			GENMASK(12, 7)
66 #define XILINX_DPDMA_EINTR_CRC_ERR(n)			BIT((n) + 13)
67 #define XILINX_DPDMA_EINTR_CRC_ERR_MASK			GENMASK(18, 13)
68 #define XILINX_DPDMA_EINTR_WR_AXI_ERR(n)		BIT((n) + 19)
69 #define XILINX_DPDMA_EINTR_WR_AXI_ERR_MASK		GENMASK(24, 19)
70 #define XILINX_DPDMA_EINTR_DESC_DONE_ERR(n)		BIT((n) + 25)
71 #define XILINX_DPDMA_EINTR_DESC_DONE_ERR_MASK		GENMASK(30, 25)
72 #define XILINX_DPDMA_EINTR_RD_CMD_FIFO_FULL		BIT(32)
73 #define XILINX_DPDMA_EINTR_CHAN_ERR_MASK		0x02082082
74 #define XILINX_DPDMA_EINTR_CHAN_ERR			0x7ffffffe
75 #define XILINX_DPDMA_EINTR_GLOBAL_ERR			0x80000001
76 #define XILINX_DPDMA_EINTR_ALL				0xffffffff
77 #define XILINX_DPDMA_CNTL				0x100
78 #define XILINX_DPDMA_GBL				0x104
79 #define XILINX_DPDMA_GBL_TRIG_MASK(n)			((n) << 0)
80 #define XILINX_DPDMA_GBL_RETRIG_MASK(n)			((n) << 6)
81 #define XILINX_DPDMA_ALC0_CNTL				0x108
82 #define XILINX_DPDMA_ALC0_STATUS			0x10c
83 #define XILINX_DPDMA_ALC0_MAX				0x110
84 #define XILINX_DPDMA_ALC0_MIN				0x114
85 #define XILINX_DPDMA_ALC0_ACC				0x118
86 #define XILINX_DPDMA_ALC0_ACC_TRAN			0x11c
87 #define XILINX_DPDMA_ALC1_CNTL				0x120
88 #define XILINX_DPDMA_ALC1_STATUS			0x124
89 #define XILINX_DPDMA_ALC1_MAX				0x128
90 #define XILINX_DPDMA_ALC1_MIN				0x12c
91 #define XILINX_DPDMA_ALC1_ACC				0x130
92 #define XILINX_DPDMA_ALC1_ACC_TRAN			0x134
93 
94 /* Channel register */
95 #define XILINX_DPDMA_CH_BASE				0x200
96 #define XILINX_DPDMA_CH_OFFSET				0x100
97 #define XILINX_DPDMA_CH_DESC_START_ADDRE		0x000
98 #define XILINX_DPDMA_CH_DESC_START_ADDRE_MASK		GENMASK(15, 0)
99 #define XILINX_DPDMA_CH_DESC_START_ADDR			0x004
100 #define XILINX_DPDMA_CH_DESC_NEXT_ADDRE			0x008
101 #define XILINX_DPDMA_CH_DESC_NEXT_ADDR			0x00c
102 #define XILINX_DPDMA_CH_PYLD_CUR_ADDRE			0x010
103 #define XILINX_DPDMA_CH_PYLD_CUR_ADDR			0x014
104 #define XILINX_DPDMA_CH_CNTL				0x018
105 #define XILINX_DPDMA_CH_CNTL_ENABLE			BIT(0)
106 #define XILINX_DPDMA_CH_CNTL_PAUSE			BIT(1)
107 #define XILINX_DPDMA_CH_CNTL_QOS_DSCR_WR_MASK		GENMASK(5, 2)
108 #define XILINX_DPDMA_CH_CNTL_QOS_DSCR_RD_MASK		GENMASK(9, 6)
109 #define XILINX_DPDMA_CH_CNTL_QOS_DATA_RD_MASK		GENMASK(13, 10)
110 #define XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS		11
111 #define XILINX_DPDMA_CH_STATUS				0x01c
112 #define XILINX_DPDMA_CH_STATUS_OTRAN_CNT_MASK		GENMASK(24, 21)
113 #define XILINX_DPDMA_CH_VDO				0x020
114 #define XILINX_DPDMA_CH_PYLD_SZ				0x024
115 #define XILINX_DPDMA_CH_DESC_ID				0x028
116 #define XILINX_DPDMA_CH_DESC_ID_MASK			GENMASK(15, 0)
117 
118 /* DPDMA descriptor fields */
119 #define XILINX_DPDMA_DESC_CONTROL_PREEMBLE		0xa5
120 #define XILINX_DPDMA_DESC_CONTROL_COMPLETE_INTR		BIT(8)
121 #define XILINX_DPDMA_DESC_CONTROL_DESC_UPDATE		BIT(9)
122 #define XILINX_DPDMA_DESC_CONTROL_IGNORE_DONE		BIT(10)
123 #define XILINX_DPDMA_DESC_CONTROL_FRAG_MODE		BIT(18)
124 #define XILINX_DPDMA_DESC_CONTROL_LAST			BIT(19)
125 #define XILINX_DPDMA_DESC_CONTROL_ENABLE_CRC		BIT(20)
126 #define XILINX_DPDMA_DESC_CONTROL_LAST_OF_FRAME		BIT(21)
127 #define XILINX_DPDMA_DESC_ID_MASK			GENMASK(15, 0)
128 #define XILINX_DPDMA_DESC_HSIZE_STRIDE_HSIZE_MASK	GENMASK(17, 0)
129 #define XILINX_DPDMA_DESC_HSIZE_STRIDE_STRIDE_MASK	GENMASK(31, 18)
130 #define XILINX_DPDMA_DESC_ADDR_EXT_NEXT_ADDR_MASK	GENMASK(15, 0)
131 #define XILINX_DPDMA_DESC_ADDR_EXT_SRC_ADDR_MASK	GENMASK(31, 16)
132 
133 #define XILINX_DPDMA_ALIGN_BYTES			256
134 #define XILINX_DPDMA_LINESIZE_ALIGN_BITS		128
135 
136 #define XILINX_DPDMA_NUM_CHAN				6
137 
138 struct xilinx_dpdma_chan;
139 
140 /**
141  * struct xilinx_dpdma_hw_desc - DPDMA hardware descriptor
142  * @control: control configuration field
143  * @desc_id: descriptor ID
144  * @xfer_size: transfer size
145  * @hsize_stride: horizontal size and stride
146  * @timestamp_lsb: LSB of time stamp
147  * @timestamp_msb: MSB of time stamp
148  * @addr_ext: upper 16 bit of 48 bit address (next_desc and src_addr)
149  * @next_desc: next descriptor 32 bit address
150  * @src_addr: payload source address (1st page, 32 LSB)
151  * @addr_ext_23: payload source address (3nd and 3rd pages, 16 LSBs)
152  * @addr_ext_45: payload source address (4th and 5th pages, 16 LSBs)
153  * @src_addr2: payload source address (2nd page, 32 LSB)
154  * @src_addr3: payload source address (3rd page, 32 LSB)
155  * @src_addr4: payload source address (4th page, 32 LSB)
156  * @src_addr5: payload source address (5th page, 32 LSB)
157  * @crc: descriptor CRC
158  */
159 struct xilinx_dpdma_hw_desc {
160 	u32 control;
161 	u32 desc_id;
162 	u32 xfer_size;
163 	u32 hsize_stride;
164 	u32 timestamp_lsb;
165 	u32 timestamp_msb;
166 	u32 addr_ext;
167 	u32 next_desc;
168 	u32 src_addr;
169 	u32 addr_ext_23;
170 	u32 addr_ext_45;
171 	u32 src_addr2;
172 	u32 src_addr3;
173 	u32 src_addr4;
174 	u32 src_addr5;
175 	u32 crc;
176 } __aligned(XILINX_DPDMA_ALIGN_BYTES);
177 
178 /**
179  * struct xilinx_dpdma_sw_desc - DPDMA software descriptor
180  * @hw: DPDMA hardware descriptor
181  * @node: list node for software descriptors
182  * @dma_addr: DMA address of the software descriptor
183  */
184 struct xilinx_dpdma_sw_desc {
185 	struct xilinx_dpdma_hw_desc hw;
186 	struct list_head node;
187 	dma_addr_t dma_addr;
188 };
189 
190 /**
191  * struct xilinx_dpdma_tx_desc - DPDMA transaction descriptor
192  * @vdesc: virtual DMA descriptor
193  * @chan: DMA channel
194  * @descriptors: list of software descriptors
195  * @error: an error has been detected with this descriptor
196  */
197 struct xilinx_dpdma_tx_desc {
198 	struct virt_dma_desc vdesc;
199 	struct xilinx_dpdma_chan *chan;
200 	struct list_head descriptors;
201 	bool error;
202 };
203 
204 #define to_dpdma_tx_desc(_desc) \
205 	container_of(_desc, struct xilinx_dpdma_tx_desc, vdesc)
206 
207 /**
208  * struct xilinx_dpdma_chan - DPDMA channel
209  * @vchan: virtual DMA channel
210  * @reg: register base address
211  * @id: channel ID
212  * @wait_to_stop: queue to wait for outstanding transacitons before stopping
213  * @running: true if the channel is running
214  * @first_frame: flag for the first frame of stream
215  * @video_group: flag if multi-channel operation is needed for video channels
216  * @lock: lock to access struct xilinx_dpdma_chan
217  * @desc_pool: descriptor allocation pool
218  * @err_task: error IRQ bottom half handler
219  * @desc: References to descriptors being processed
220  * @desc.pending: Descriptor schedule to the hardware, pending execution
221  * @desc.active: Descriptor being executed by the hardware
222  * @xdev: DPDMA device
223  */
224 struct xilinx_dpdma_chan {
225 	struct virt_dma_chan vchan;
226 	void __iomem *reg;
227 	unsigned int id;
228 
229 	wait_queue_head_t wait_to_stop;
230 	bool running;
231 	bool first_frame;
232 	bool video_group;
233 
234 	spinlock_t lock; /* lock to access struct xilinx_dpdma_chan */
235 	struct dma_pool *desc_pool;
236 	struct tasklet_struct err_task;
237 
238 	struct {
239 		struct xilinx_dpdma_tx_desc *pending;
240 		struct xilinx_dpdma_tx_desc *active;
241 	} desc;
242 
243 	struct xilinx_dpdma_device *xdev;
244 };
245 
246 #define to_xilinx_chan(_chan) \
247 	container_of(_chan, struct xilinx_dpdma_chan, vchan.chan)
248 
249 /**
250  * struct xilinx_dpdma_device - DPDMA device
251  * @common: generic dma device structure
252  * @reg: register base address
253  * @dev: generic device structure
254  * @irq: the interrupt number
255  * @axi_clk: axi clock
256  * @chan: DPDMA channels
257  * @ext_addr: flag for 64 bit system (48 bit addressing)
258  */
259 struct xilinx_dpdma_device {
260 	struct dma_device common;
261 	void __iomem *reg;
262 	struct device *dev;
263 	int irq;
264 
265 	struct clk *axi_clk;
266 	struct xilinx_dpdma_chan *chan[XILINX_DPDMA_NUM_CHAN];
267 
268 	bool ext_addr;
269 };
270 
271 /* -----------------------------------------------------------------------------
272  * DebugFS
273  */
274 #define XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE	32
275 #define XILINX_DPDMA_DEBUGFS_UINT16_MAX_STR	"65535"
276 
277 /* Match xilinx_dpdma_testcases vs dpdma_debugfs_reqs[] entry */
278 enum xilinx_dpdma_testcases {
279 	DPDMA_TC_INTR_DONE,
280 	DPDMA_TC_NONE
281 };
282 
283 struct xilinx_dpdma_debugfs {
284 	enum xilinx_dpdma_testcases testcase;
285 	u16 xilinx_dpdma_irq_done_count;
286 	unsigned int chan_id;
287 };
288 
289 static struct xilinx_dpdma_debugfs dpdma_debugfs;
290 struct xilinx_dpdma_debugfs_request {
291 	const char *name;
292 	enum xilinx_dpdma_testcases tc;
293 	ssize_t (*read)(char *buf);
294 	int (*write)(char *args);
295 };
296 
297 static void xilinx_dpdma_debugfs_desc_done_irq(struct xilinx_dpdma_chan *chan)
298 {
299 	if (IS_ENABLED(CONFIG_DEBUG_FS) && chan->id == dpdma_debugfs.chan_id)
300 		dpdma_debugfs.xilinx_dpdma_irq_done_count++;
301 }
302 
303 static ssize_t xilinx_dpdma_debugfs_desc_done_irq_read(char *buf)
304 {
305 	size_t out_str_len;
306 
307 	dpdma_debugfs.testcase = DPDMA_TC_NONE;
308 
309 	out_str_len = strlen(XILINX_DPDMA_DEBUGFS_UINT16_MAX_STR);
310 	out_str_len = min_t(size_t, XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE,
311 			    out_str_len);
312 	snprintf(buf, out_str_len, "%d",
313 		 dpdma_debugfs.xilinx_dpdma_irq_done_count);
314 
315 	return 0;
316 }
317 
318 static int xilinx_dpdma_debugfs_desc_done_irq_write(char *args)
319 {
320 	char *arg;
321 	int ret;
322 	u32 id;
323 
324 	arg = strsep(&args, " ");
325 	if (!arg || strncasecmp(arg, "start", 5))
326 		return -EINVAL;
327 
328 	arg = strsep(&args, " ");
329 	if (!arg)
330 		return -EINVAL;
331 
332 	ret = kstrtou32(arg, 0, &id);
333 	if (ret < 0)
334 		return ret;
335 
336 	if (id < ZYNQMP_DPDMA_VIDEO0 || id > ZYNQMP_DPDMA_AUDIO1)
337 		return -EINVAL;
338 
339 	dpdma_debugfs.testcase = DPDMA_TC_INTR_DONE;
340 	dpdma_debugfs.xilinx_dpdma_irq_done_count = 0;
341 	dpdma_debugfs.chan_id = id;
342 
343 	return 0;
344 }
345 
346 /* Match xilinx_dpdma_testcases vs dpdma_debugfs_reqs[] entry */
347 static struct xilinx_dpdma_debugfs_request dpdma_debugfs_reqs[] = {
348 	{
349 		.name = "DESCRIPTOR_DONE_INTR",
350 		.tc = DPDMA_TC_INTR_DONE,
351 		.read = xilinx_dpdma_debugfs_desc_done_irq_read,
352 		.write = xilinx_dpdma_debugfs_desc_done_irq_write,
353 	},
354 };
355 
356 static ssize_t xilinx_dpdma_debugfs_read(struct file *f, char __user *buf,
357 					 size_t size, loff_t *pos)
358 {
359 	enum xilinx_dpdma_testcases testcase;
360 	char *kern_buff;
361 	int ret = 0;
362 
363 	if (*pos != 0 || size <= 0)
364 		return -EINVAL;
365 
366 	kern_buff = kzalloc(XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE, GFP_KERNEL);
367 	if (!kern_buff) {
368 		dpdma_debugfs.testcase = DPDMA_TC_NONE;
369 		return -ENOMEM;
370 	}
371 
372 	testcase = READ_ONCE(dpdma_debugfs.testcase);
373 	if (testcase != DPDMA_TC_NONE) {
374 		ret = dpdma_debugfs_reqs[testcase].read(kern_buff);
375 		if (ret < 0)
376 			goto done;
377 	} else {
378 		strlcpy(kern_buff, "No testcase executed",
379 			XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE);
380 	}
381 
382 	size = min(size, strlen(kern_buff));
383 	if (copy_to_user(buf, kern_buff, size))
384 		ret = -EFAULT;
385 
386 done:
387 	kfree(kern_buff);
388 	if (ret)
389 		return ret;
390 
391 	*pos = size + 1;
392 	return size;
393 }
394 
395 static ssize_t xilinx_dpdma_debugfs_write(struct file *f,
396 					  const char __user *buf, size_t size,
397 					  loff_t *pos)
398 {
399 	char *kern_buff, *kern_buff_start;
400 	char *testcase;
401 	unsigned int i;
402 	int ret;
403 
404 	if (*pos != 0 || size <= 0)
405 		return -EINVAL;
406 
407 	/* Supporting single instance of test as of now. */
408 	if (dpdma_debugfs.testcase != DPDMA_TC_NONE)
409 		return -EBUSY;
410 
411 	kern_buff = kzalloc(size, GFP_KERNEL);
412 	if (!kern_buff)
413 		return -ENOMEM;
414 	kern_buff_start = kern_buff;
415 
416 	ret = strncpy_from_user(kern_buff, buf, size);
417 	if (ret < 0)
418 		goto done;
419 
420 	/* Read the testcase name from a user request. */
421 	testcase = strsep(&kern_buff, " ");
422 
423 	for (i = 0; i < ARRAY_SIZE(dpdma_debugfs_reqs); i++) {
424 		if (!strcasecmp(testcase, dpdma_debugfs_reqs[i].name))
425 			break;
426 	}
427 
428 	if (i == ARRAY_SIZE(dpdma_debugfs_reqs)) {
429 		ret = -EINVAL;
430 		goto done;
431 	}
432 
433 	ret = dpdma_debugfs_reqs[i].write(kern_buff);
434 	if (ret < 0)
435 		goto done;
436 
437 	ret = size;
438 
439 done:
440 	kfree(kern_buff_start);
441 	return ret;
442 }
443 
444 static const struct file_operations fops_xilinx_dpdma_dbgfs = {
445 	.owner = THIS_MODULE,
446 	.read = xilinx_dpdma_debugfs_read,
447 	.write = xilinx_dpdma_debugfs_write,
448 };
449 
450 static void xilinx_dpdma_debugfs_init(struct xilinx_dpdma_device *xdev)
451 {
452 	struct dentry *dent;
453 
454 	dpdma_debugfs.testcase = DPDMA_TC_NONE;
455 
456 	dent = debugfs_create_file("testcase", 0444, xdev->common.dbg_dev_root,
457 				   NULL, &fops_xilinx_dpdma_dbgfs);
458 	if (IS_ERR(dent))
459 		dev_err(xdev->dev, "Failed to create debugfs testcase file\n");
460 }
461 
462 /* -----------------------------------------------------------------------------
463  * I/O Accessors
464  */
465 
466 static inline u32 dpdma_read(void __iomem *base, u32 offset)
467 {
468 	return ioread32(base + offset);
469 }
470 
471 static inline void dpdma_write(void __iomem *base, u32 offset, u32 val)
472 {
473 	iowrite32(val, base + offset);
474 }
475 
476 static inline void dpdma_clr(void __iomem *base, u32 offset, u32 clr)
477 {
478 	dpdma_write(base, offset, dpdma_read(base, offset) & ~clr);
479 }
480 
481 static inline void dpdma_set(void __iomem *base, u32 offset, u32 set)
482 {
483 	dpdma_write(base, offset, dpdma_read(base, offset) | set);
484 }
485 
486 /* -----------------------------------------------------------------------------
487  * Descriptor Operations
488  */
489 
490 /**
491  * xilinx_dpdma_sw_desc_set_dma_addrs - Set DMA addresses in the descriptor
492  * @xdev: DPDMA device
493  * @sw_desc: The software descriptor in which to set DMA addresses
494  * @prev: The previous descriptor
495  * @dma_addr: array of dma addresses
496  * @num_src_addr: number of addresses in @dma_addr
497  *
498  * Set all the DMA addresses in the hardware descriptor corresponding to @dev
499  * from @dma_addr. If a previous descriptor is specified in @prev, its next
500  * descriptor DMA address is set to the DMA address of @sw_desc. @prev may be
501  * identical to @sw_desc for cyclic transfers.
502  */
503 static void xilinx_dpdma_sw_desc_set_dma_addrs(struct xilinx_dpdma_device *xdev,
504 					       struct xilinx_dpdma_sw_desc *sw_desc,
505 					       struct xilinx_dpdma_sw_desc *prev,
506 					       dma_addr_t dma_addr[],
507 					       unsigned int num_src_addr)
508 {
509 	struct xilinx_dpdma_hw_desc *hw_desc = &sw_desc->hw;
510 	unsigned int i;
511 
512 	hw_desc->src_addr = lower_32_bits(dma_addr[0]);
513 	if (xdev->ext_addr)
514 		hw_desc->addr_ext |=
515 			FIELD_PREP(XILINX_DPDMA_DESC_ADDR_EXT_SRC_ADDR_MASK,
516 				   upper_32_bits(dma_addr[0]));
517 
518 	for (i = 1; i < num_src_addr; i++) {
519 		u32 *addr = &hw_desc->src_addr2;
520 
521 		addr[i - 1] = lower_32_bits(dma_addr[i]);
522 
523 		if (xdev->ext_addr) {
524 			u32 *addr_ext = &hw_desc->addr_ext_23;
525 			u32 addr_msb;
526 
527 			addr_msb = upper_32_bits(dma_addr[i]) & GENMASK(15, 0);
528 			addr_msb <<= 16 * ((i - 1) % 2);
529 			addr_ext[(i - 1) / 2] |= addr_msb;
530 		}
531 	}
532 
533 	if (!prev)
534 		return;
535 
536 	prev->hw.next_desc = lower_32_bits(sw_desc->dma_addr);
537 	if (xdev->ext_addr)
538 		prev->hw.addr_ext |=
539 			FIELD_PREP(XILINX_DPDMA_DESC_ADDR_EXT_NEXT_ADDR_MASK,
540 				   upper_32_bits(sw_desc->dma_addr));
541 }
542 
543 /**
544  * xilinx_dpdma_chan_alloc_sw_desc - Allocate a software descriptor
545  * @chan: DPDMA channel
546  *
547  * Allocate a software descriptor from the channel's descriptor pool.
548  *
549  * Return: a software descriptor or NULL.
550  */
551 static struct xilinx_dpdma_sw_desc *
552 xilinx_dpdma_chan_alloc_sw_desc(struct xilinx_dpdma_chan *chan)
553 {
554 	struct xilinx_dpdma_sw_desc *sw_desc;
555 	dma_addr_t dma_addr;
556 
557 	sw_desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &dma_addr);
558 	if (!sw_desc)
559 		return NULL;
560 
561 	sw_desc->dma_addr = dma_addr;
562 
563 	return sw_desc;
564 }
565 
566 /**
567  * xilinx_dpdma_chan_free_sw_desc - Free a software descriptor
568  * @chan: DPDMA channel
569  * @sw_desc: software descriptor to free
570  *
571  * Free a software descriptor from the channel's descriptor pool.
572  */
573 static void
574 xilinx_dpdma_chan_free_sw_desc(struct xilinx_dpdma_chan *chan,
575 			       struct xilinx_dpdma_sw_desc *sw_desc)
576 {
577 	dma_pool_free(chan->desc_pool, sw_desc, sw_desc->dma_addr);
578 }
579 
580 /**
581  * xilinx_dpdma_chan_dump_tx_desc - Dump a tx descriptor
582  * @chan: DPDMA channel
583  * @tx_desc: tx descriptor to dump
584  *
585  * Dump contents of a tx descriptor
586  */
587 static void xilinx_dpdma_chan_dump_tx_desc(struct xilinx_dpdma_chan *chan,
588 					   struct xilinx_dpdma_tx_desc *tx_desc)
589 {
590 	struct xilinx_dpdma_sw_desc *sw_desc;
591 	struct device *dev = chan->xdev->dev;
592 	unsigned int i = 0;
593 
594 	dev_dbg(dev, "------- TX descriptor dump start -------\n");
595 	dev_dbg(dev, "------- channel ID = %d -------\n", chan->id);
596 
597 	list_for_each_entry(sw_desc, &tx_desc->descriptors, node) {
598 		struct xilinx_dpdma_hw_desc *hw_desc = &sw_desc->hw;
599 
600 		dev_dbg(dev, "------- HW descriptor %d -------\n", i++);
601 		dev_dbg(dev, "descriptor DMA addr: %pad\n", &sw_desc->dma_addr);
602 		dev_dbg(dev, "control: 0x%08x\n", hw_desc->control);
603 		dev_dbg(dev, "desc_id: 0x%08x\n", hw_desc->desc_id);
604 		dev_dbg(dev, "xfer_size: 0x%08x\n", hw_desc->xfer_size);
605 		dev_dbg(dev, "hsize_stride: 0x%08x\n", hw_desc->hsize_stride);
606 		dev_dbg(dev, "timestamp_lsb: 0x%08x\n", hw_desc->timestamp_lsb);
607 		dev_dbg(dev, "timestamp_msb: 0x%08x\n", hw_desc->timestamp_msb);
608 		dev_dbg(dev, "addr_ext: 0x%08x\n", hw_desc->addr_ext);
609 		dev_dbg(dev, "next_desc: 0x%08x\n", hw_desc->next_desc);
610 		dev_dbg(dev, "src_addr: 0x%08x\n", hw_desc->src_addr);
611 		dev_dbg(dev, "addr_ext_23: 0x%08x\n", hw_desc->addr_ext_23);
612 		dev_dbg(dev, "addr_ext_45: 0x%08x\n", hw_desc->addr_ext_45);
613 		dev_dbg(dev, "src_addr2: 0x%08x\n", hw_desc->src_addr2);
614 		dev_dbg(dev, "src_addr3: 0x%08x\n", hw_desc->src_addr3);
615 		dev_dbg(dev, "src_addr4: 0x%08x\n", hw_desc->src_addr4);
616 		dev_dbg(dev, "src_addr5: 0x%08x\n", hw_desc->src_addr5);
617 		dev_dbg(dev, "crc: 0x%08x\n", hw_desc->crc);
618 	}
619 
620 	dev_dbg(dev, "------- TX descriptor dump end -------\n");
621 }
622 
623 /**
624  * xilinx_dpdma_chan_alloc_tx_desc - Allocate a transaction descriptor
625  * @chan: DPDMA channel
626  *
627  * Allocate a tx descriptor.
628  *
629  * Return: a tx descriptor or NULL.
630  */
631 static struct xilinx_dpdma_tx_desc *
632 xilinx_dpdma_chan_alloc_tx_desc(struct xilinx_dpdma_chan *chan)
633 {
634 	struct xilinx_dpdma_tx_desc *tx_desc;
635 
636 	tx_desc = kzalloc(sizeof(*tx_desc), GFP_NOWAIT);
637 	if (!tx_desc)
638 		return NULL;
639 
640 	INIT_LIST_HEAD(&tx_desc->descriptors);
641 	tx_desc->chan = chan;
642 	tx_desc->error = false;
643 
644 	return tx_desc;
645 }
646 
647 /**
648  * xilinx_dpdma_chan_free_tx_desc - Free a virtual DMA descriptor
649  * @vdesc: virtual DMA descriptor
650  *
651  * Free the virtual DMA descriptor @vdesc including its software descriptors.
652  */
653 static void xilinx_dpdma_chan_free_tx_desc(struct virt_dma_desc *vdesc)
654 {
655 	struct xilinx_dpdma_sw_desc *sw_desc, *next;
656 	struct xilinx_dpdma_tx_desc *desc;
657 
658 	if (!vdesc)
659 		return;
660 
661 	desc = to_dpdma_tx_desc(vdesc);
662 
663 	list_for_each_entry_safe(sw_desc, next, &desc->descriptors, node) {
664 		list_del(&sw_desc->node);
665 		xilinx_dpdma_chan_free_sw_desc(desc->chan, sw_desc);
666 	}
667 
668 	kfree(desc);
669 }
670 
671 /**
672  * xilinx_dpdma_chan_prep_interleaved_dma - Prepare an interleaved dma
673  *					    descriptor
674  * @chan: DPDMA channel
675  * @xt: dma interleaved template
676  *
677  * Prepare a tx descriptor including internal software/hardware descriptors
678  * based on @xt.
679  *
680  * Return: A DPDMA TX descriptor on success, or NULL.
681  */
682 static struct xilinx_dpdma_tx_desc *
683 xilinx_dpdma_chan_prep_interleaved_dma(struct xilinx_dpdma_chan *chan,
684 				       struct dma_interleaved_template *xt)
685 {
686 	struct xilinx_dpdma_tx_desc *tx_desc;
687 	struct xilinx_dpdma_sw_desc *sw_desc;
688 	struct xilinx_dpdma_hw_desc *hw_desc;
689 	size_t hsize = xt->sgl[0].size;
690 	size_t stride = hsize + xt->sgl[0].icg;
691 
692 	if (!IS_ALIGNED(xt->src_start, XILINX_DPDMA_ALIGN_BYTES)) {
693 		dev_err(chan->xdev->dev,
694 			"chan%u: buffer should be aligned at %d B\n",
695 			chan->id, XILINX_DPDMA_ALIGN_BYTES);
696 		return NULL;
697 	}
698 
699 	tx_desc = xilinx_dpdma_chan_alloc_tx_desc(chan);
700 	if (!tx_desc)
701 		return NULL;
702 
703 	sw_desc = xilinx_dpdma_chan_alloc_sw_desc(chan);
704 	if (!sw_desc) {
705 		xilinx_dpdma_chan_free_tx_desc(&tx_desc->vdesc);
706 		return NULL;
707 	}
708 
709 	xilinx_dpdma_sw_desc_set_dma_addrs(chan->xdev, sw_desc, sw_desc,
710 					   &xt->src_start, 1);
711 
712 	hw_desc = &sw_desc->hw;
713 	hsize = ALIGN(hsize, XILINX_DPDMA_LINESIZE_ALIGN_BITS / 8);
714 	hw_desc->xfer_size = hsize * xt->numf;
715 	hw_desc->hsize_stride =
716 		FIELD_PREP(XILINX_DPDMA_DESC_HSIZE_STRIDE_HSIZE_MASK, hsize) |
717 		FIELD_PREP(XILINX_DPDMA_DESC_HSIZE_STRIDE_STRIDE_MASK,
718 			   stride / 16);
719 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_PREEMBLE;
720 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_COMPLETE_INTR;
721 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_IGNORE_DONE;
722 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_LAST_OF_FRAME;
723 
724 	list_add_tail(&sw_desc->node, &tx_desc->descriptors);
725 
726 	return tx_desc;
727 }
728 
729 /* -----------------------------------------------------------------------------
730  * DPDMA Channel Operations
731  */
732 
733 /**
734  * xilinx_dpdma_chan_enable - Enable the channel
735  * @chan: DPDMA channel
736  *
737  * Enable the channel and its interrupts. Set the QoS values for video class.
738  */
739 static void xilinx_dpdma_chan_enable(struct xilinx_dpdma_chan *chan)
740 {
741 	u32 reg;
742 
743 	reg = (XILINX_DPDMA_INTR_CHAN_MASK << chan->id)
744 	    | XILINX_DPDMA_INTR_GLOBAL_MASK;
745 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN, reg);
746 	reg = (XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id)
747 	    | XILINX_DPDMA_INTR_GLOBAL_ERR;
748 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_EIEN, reg);
749 
750 	reg = XILINX_DPDMA_CH_CNTL_ENABLE
751 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DSCR_WR_MASK,
752 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS)
753 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DSCR_RD_MASK,
754 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS)
755 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DATA_RD_MASK,
756 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS);
757 	dpdma_set(chan->reg, XILINX_DPDMA_CH_CNTL, reg);
758 }
759 
760 /**
761  * xilinx_dpdma_chan_disable - Disable the channel
762  * @chan: DPDMA channel
763  *
764  * Disable the channel and its interrupts.
765  */
766 static void xilinx_dpdma_chan_disable(struct xilinx_dpdma_chan *chan)
767 {
768 	u32 reg;
769 
770 	reg = XILINX_DPDMA_INTR_CHAN_MASK << chan->id;
771 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN, reg);
772 	reg = XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id;
773 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_EIEN, reg);
774 
775 	dpdma_clr(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_ENABLE);
776 }
777 
778 /**
779  * xilinx_dpdma_chan_pause - Pause the channel
780  * @chan: DPDMA channel
781  *
782  * Pause the channel.
783  */
784 static void xilinx_dpdma_chan_pause(struct xilinx_dpdma_chan *chan)
785 {
786 	dpdma_set(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_PAUSE);
787 }
788 
789 /**
790  * xilinx_dpdma_chan_unpause - Unpause the channel
791  * @chan: DPDMA channel
792  *
793  * Unpause the channel.
794  */
795 static void xilinx_dpdma_chan_unpause(struct xilinx_dpdma_chan *chan)
796 {
797 	dpdma_clr(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_PAUSE);
798 }
799 
800 static u32 xilinx_dpdma_chan_video_group_ready(struct xilinx_dpdma_chan *chan)
801 {
802 	struct xilinx_dpdma_device *xdev = chan->xdev;
803 	u32 channels = 0;
804 	unsigned int i;
805 
806 	for (i = ZYNQMP_DPDMA_VIDEO0; i <= ZYNQMP_DPDMA_VIDEO2; i++) {
807 		if (xdev->chan[i]->video_group && !xdev->chan[i]->running)
808 			return 0;
809 
810 		if (xdev->chan[i]->video_group)
811 			channels |= BIT(i);
812 	}
813 
814 	return channels;
815 }
816 
817 /**
818  * xilinx_dpdma_chan_queue_transfer - Queue the next transfer
819  * @chan: DPDMA channel
820  *
821  * Queue the next descriptor, if any, to the hardware. If the channel is
822  * stopped, start it first. Otherwise retrigger it with the next descriptor.
823  */
824 static void xilinx_dpdma_chan_queue_transfer(struct xilinx_dpdma_chan *chan)
825 {
826 	struct xilinx_dpdma_device *xdev = chan->xdev;
827 	struct xilinx_dpdma_sw_desc *sw_desc;
828 	struct xilinx_dpdma_tx_desc *desc;
829 	struct virt_dma_desc *vdesc;
830 	u32 reg, channels;
831 	bool first_frame;
832 
833 	lockdep_assert_held(&chan->lock);
834 
835 	if (chan->desc.pending)
836 		return;
837 
838 	if (!chan->running) {
839 		xilinx_dpdma_chan_unpause(chan);
840 		xilinx_dpdma_chan_enable(chan);
841 		chan->first_frame = true;
842 		chan->running = true;
843 	}
844 
845 	vdesc = vchan_next_desc(&chan->vchan);
846 	if (!vdesc)
847 		return;
848 
849 	desc = to_dpdma_tx_desc(vdesc);
850 	chan->desc.pending = desc;
851 	list_del(&desc->vdesc.node);
852 
853 	/*
854 	 * Assign the cookie to descriptors in this transaction. Only 16 bit
855 	 * will be used, but it should be enough.
856 	 */
857 	list_for_each_entry(sw_desc, &desc->descriptors, node)
858 		sw_desc->hw.desc_id = desc->vdesc.tx.cookie
859 				    & XILINX_DPDMA_CH_DESC_ID_MASK;
860 
861 	sw_desc = list_first_entry(&desc->descriptors,
862 				   struct xilinx_dpdma_sw_desc, node);
863 	dpdma_write(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDR,
864 		    lower_32_bits(sw_desc->dma_addr));
865 	if (xdev->ext_addr)
866 		dpdma_write(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDRE,
867 			    FIELD_PREP(XILINX_DPDMA_CH_DESC_START_ADDRE_MASK,
868 				       upper_32_bits(sw_desc->dma_addr)));
869 
870 	first_frame = chan->first_frame;
871 	chan->first_frame = false;
872 
873 	if (chan->video_group) {
874 		channels = xilinx_dpdma_chan_video_group_ready(chan);
875 		/*
876 		 * Trigger the transfer only when all channels in the group are
877 		 * ready.
878 		 */
879 		if (!channels)
880 			return;
881 	} else {
882 		channels = BIT(chan->id);
883 	}
884 
885 	if (first_frame)
886 		reg = XILINX_DPDMA_GBL_TRIG_MASK(channels);
887 	else
888 		reg = XILINX_DPDMA_GBL_RETRIG_MASK(channels);
889 
890 	dpdma_write(xdev->reg, XILINX_DPDMA_GBL, reg);
891 }
892 
893 /**
894  * xilinx_dpdma_chan_ostand - Number of outstanding transactions
895  * @chan: DPDMA channel
896  *
897  * Read and return the number of outstanding transactions from register.
898  *
899  * Return: Number of outstanding transactions from the status register.
900  */
901 static u32 xilinx_dpdma_chan_ostand(struct xilinx_dpdma_chan *chan)
902 {
903 	return FIELD_GET(XILINX_DPDMA_CH_STATUS_OTRAN_CNT_MASK,
904 			 dpdma_read(chan->reg, XILINX_DPDMA_CH_STATUS));
905 }
906 
907 /**
908  * xilinx_dpdma_chan_notify_no_ostand - Notify no outstanding transaction event
909  * @chan: DPDMA channel
910  *
911  * Notify waiters for no outstanding event, so waiters can stop the channel
912  * safely. This function is supposed to be called when 'no outstanding'
913  * interrupt is generated. The 'no outstanding' interrupt is disabled and
914  * should be re-enabled when this event is handled. If the channel status
915  * register still shows some number of outstanding transactions, the interrupt
916  * remains enabled.
917  *
918  * Return: 0 on success. On failure, -EWOULDBLOCK if there's still outstanding
919  * transaction(s).
920  */
921 static int xilinx_dpdma_chan_notify_no_ostand(struct xilinx_dpdma_chan *chan)
922 {
923 	u32 cnt;
924 
925 	cnt = xilinx_dpdma_chan_ostand(chan);
926 	if (cnt) {
927 		dev_dbg(chan->xdev->dev,
928 			"chan%u: %d outstanding transactions\n",
929 			chan->id, cnt);
930 		return -EWOULDBLOCK;
931 	}
932 
933 	/* Disable 'no outstanding' interrupt */
934 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IDS,
935 		    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
936 	wake_up(&chan->wait_to_stop);
937 
938 	return 0;
939 }
940 
941 /**
942  * xilinx_dpdma_chan_wait_no_ostand - Wait for the no outstanding irq
943  * @chan: DPDMA channel
944  *
945  * Wait for the no outstanding transaction interrupt. This functions can sleep
946  * for 50ms.
947  *
948  * Return: 0 on success. On failure, -ETIMEOUT for time out, or the error code
949  * from wait_event_interruptible_timeout().
950  */
951 static int xilinx_dpdma_chan_wait_no_ostand(struct xilinx_dpdma_chan *chan)
952 {
953 	int ret;
954 
955 	/* Wait for a no outstanding transaction interrupt upto 50msec */
956 	ret = wait_event_interruptible_timeout(chan->wait_to_stop,
957 					       !xilinx_dpdma_chan_ostand(chan),
958 					       msecs_to_jiffies(50));
959 	if (ret > 0) {
960 		dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN,
961 			    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
962 		return 0;
963 	}
964 
965 	dev_err(chan->xdev->dev, "chan%u: not ready to stop: %d trans\n",
966 		chan->id, xilinx_dpdma_chan_ostand(chan));
967 
968 	if (ret == 0)
969 		return -ETIMEDOUT;
970 
971 	return ret;
972 }
973 
974 /**
975  * xilinx_dpdma_chan_poll_no_ostand - Poll the outstanding transaction status
976  * @chan: DPDMA channel
977  *
978  * Poll the outstanding transaction status, and return when there's no
979  * outstanding transaction. This functions can be used in the interrupt context
980  * or where the atomicity is required. Calling thread may wait more than 50ms.
981  *
982  * Return: 0 on success, or -ETIMEDOUT.
983  */
984 static int xilinx_dpdma_chan_poll_no_ostand(struct xilinx_dpdma_chan *chan)
985 {
986 	u32 cnt, loop = 50000;
987 
988 	/* Poll at least for 50ms (20 fps). */
989 	do {
990 		cnt = xilinx_dpdma_chan_ostand(chan);
991 		udelay(1);
992 	} while (loop-- > 0 && cnt);
993 
994 	if (loop) {
995 		dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN,
996 			    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
997 		return 0;
998 	}
999 
1000 	dev_err(chan->xdev->dev, "chan%u: not ready to stop: %d trans\n",
1001 		chan->id, xilinx_dpdma_chan_ostand(chan));
1002 
1003 	return -ETIMEDOUT;
1004 }
1005 
1006 /**
1007  * xilinx_dpdma_chan_stop - Stop the channel
1008  * @chan: DPDMA channel
1009  *
1010  * Stop a previously paused channel by first waiting for completion of all
1011  * outstanding transaction and then disabling the channel.
1012  *
1013  * Return: 0 on success, or -ETIMEDOUT if the channel failed to stop.
1014  */
1015 static int xilinx_dpdma_chan_stop(struct xilinx_dpdma_chan *chan)
1016 {
1017 	unsigned long flags;
1018 	int ret;
1019 
1020 	ret = xilinx_dpdma_chan_wait_no_ostand(chan);
1021 	if (ret)
1022 		return ret;
1023 
1024 	spin_lock_irqsave(&chan->lock, flags);
1025 	xilinx_dpdma_chan_disable(chan);
1026 	chan->running = false;
1027 	spin_unlock_irqrestore(&chan->lock, flags);
1028 
1029 	return 0;
1030 }
1031 
1032 /**
1033  * xilinx_dpdma_chan_done_irq - Handle hardware descriptor completion
1034  * @chan: DPDMA channel
1035  *
1036  * Handle completion of the currently active descriptor (@chan->desc.active). As
1037  * we currently support cyclic transfers only, this just invokes the cyclic
1038  * callback. The descriptor will be completed at the VSYNC interrupt when a new
1039  * descriptor replaces it.
1040  */
1041 static void xilinx_dpdma_chan_done_irq(struct xilinx_dpdma_chan *chan)
1042 {
1043 	struct xilinx_dpdma_tx_desc *active;
1044 	unsigned long flags;
1045 
1046 	spin_lock_irqsave(&chan->lock, flags);
1047 
1048 	xilinx_dpdma_debugfs_desc_done_irq(chan);
1049 
1050 	active = chan->desc.active;
1051 	if (active)
1052 		vchan_cyclic_callback(&active->vdesc);
1053 	else
1054 		dev_warn(chan->xdev->dev,
1055 			 "chan%u: DONE IRQ with no active descriptor!\n",
1056 			 chan->id);
1057 
1058 	spin_unlock_irqrestore(&chan->lock, flags);
1059 }
1060 
1061 /**
1062  * xilinx_dpdma_chan_vsync_irq - Handle hardware descriptor scheduling
1063  * @chan: DPDMA channel
1064  *
1065  * At VSYNC the active descriptor may have been replaced by the pending
1066  * descriptor. Detect this through the DESC_ID and perform appropriate
1067  * bookkeeping.
1068  */
1069 static void xilinx_dpdma_chan_vsync_irq(struct  xilinx_dpdma_chan *chan)
1070 {
1071 	struct xilinx_dpdma_tx_desc *pending;
1072 	struct xilinx_dpdma_sw_desc *sw_desc;
1073 	unsigned long flags;
1074 	u32 desc_id;
1075 
1076 	spin_lock_irqsave(&chan->lock, flags);
1077 
1078 	pending = chan->desc.pending;
1079 	if (!chan->running || !pending)
1080 		goto out;
1081 
1082 	desc_id = dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_ID)
1083 		& XILINX_DPDMA_CH_DESC_ID_MASK;
1084 
1085 	/* If the retrigger raced with vsync, retry at the next frame. */
1086 	sw_desc = list_first_entry(&pending->descriptors,
1087 				   struct xilinx_dpdma_sw_desc, node);
1088 	if (sw_desc->hw.desc_id != desc_id) {
1089 		dev_dbg(chan->xdev->dev,
1090 			"chan%u: vsync race lost (%u != %u), retrying\n",
1091 			chan->id, sw_desc->hw.desc_id, desc_id);
1092 		goto out;
1093 	}
1094 
1095 	/*
1096 	 * Complete the active descriptor, if any, promote the pending
1097 	 * descriptor to active, and queue the next transfer, if any.
1098 	 */
1099 	if (chan->desc.active)
1100 		vchan_cookie_complete(&chan->desc.active->vdesc);
1101 	chan->desc.active = pending;
1102 	chan->desc.pending = NULL;
1103 
1104 	xilinx_dpdma_chan_queue_transfer(chan);
1105 
1106 out:
1107 	spin_unlock_irqrestore(&chan->lock, flags);
1108 }
1109 
1110 /**
1111  * xilinx_dpdma_chan_err - Detect any channel error
1112  * @chan: DPDMA channel
1113  * @isr: masked Interrupt Status Register
1114  * @eisr: Error Interrupt Status Register
1115  *
1116  * Return: true if any channel error occurs, or false otherwise.
1117  */
1118 static bool
1119 xilinx_dpdma_chan_err(struct xilinx_dpdma_chan *chan, u32 isr, u32 eisr)
1120 {
1121 	if (!chan)
1122 		return false;
1123 
1124 	if (chan->running &&
1125 	    ((isr & (XILINX_DPDMA_INTR_CHAN_ERR_MASK << chan->id)) ||
1126 	    (eisr & (XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id))))
1127 		return true;
1128 
1129 	return false;
1130 }
1131 
1132 /**
1133  * xilinx_dpdma_chan_handle_err - DPDMA channel error handling
1134  * @chan: DPDMA channel
1135  *
1136  * This function is called when any channel error or any global error occurs.
1137  * The function disables the paused channel by errors and determines
1138  * if the current active descriptor can be rescheduled depending on
1139  * the descriptor status.
1140  */
1141 static void xilinx_dpdma_chan_handle_err(struct xilinx_dpdma_chan *chan)
1142 {
1143 	struct xilinx_dpdma_device *xdev = chan->xdev;
1144 	struct xilinx_dpdma_tx_desc *active;
1145 	unsigned long flags;
1146 
1147 	spin_lock_irqsave(&chan->lock, flags);
1148 
1149 	dev_dbg(xdev->dev, "chan%u: cur desc addr = 0x%04x%08x\n",
1150 		chan->id,
1151 		dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDRE),
1152 		dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDR));
1153 	dev_dbg(xdev->dev, "chan%u: cur payload addr = 0x%04x%08x\n",
1154 		chan->id,
1155 		dpdma_read(chan->reg, XILINX_DPDMA_CH_PYLD_CUR_ADDRE),
1156 		dpdma_read(chan->reg, XILINX_DPDMA_CH_PYLD_CUR_ADDR));
1157 
1158 	xilinx_dpdma_chan_disable(chan);
1159 	chan->running = false;
1160 
1161 	if (!chan->desc.active)
1162 		goto out_unlock;
1163 
1164 	active = chan->desc.active;
1165 	chan->desc.active = NULL;
1166 
1167 	xilinx_dpdma_chan_dump_tx_desc(chan, active);
1168 
1169 	if (active->error)
1170 		dev_dbg(xdev->dev, "chan%u: repeated error on desc\n",
1171 			chan->id);
1172 
1173 	/* Reschedule if there's no new descriptor */
1174 	if (!chan->desc.pending &&
1175 	    list_empty(&chan->vchan.desc_issued)) {
1176 		active->error = true;
1177 		list_add_tail(&active->vdesc.node,
1178 			      &chan->vchan.desc_issued);
1179 	} else {
1180 		xilinx_dpdma_chan_free_tx_desc(&active->vdesc);
1181 	}
1182 
1183 out_unlock:
1184 	spin_unlock_irqrestore(&chan->lock, flags);
1185 }
1186 
1187 /* -----------------------------------------------------------------------------
1188  * DMA Engine Operations
1189  */
1190 
1191 static struct dma_async_tx_descriptor *
1192 xilinx_dpdma_prep_interleaved_dma(struct dma_chan *dchan,
1193 				  struct dma_interleaved_template *xt,
1194 				  unsigned long flags)
1195 {
1196 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1197 	struct xilinx_dpdma_tx_desc *desc;
1198 
1199 	if (xt->dir != DMA_MEM_TO_DEV)
1200 		return NULL;
1201 
1202 	if (!xt->numf || !xt->sgl[0].size)
1203 		return NULL;
1204 
1205 	if (!(flags & DMA_PREP_REPEAT) || !(flags & DMA_PREP_LOAD_EOT))
1206 		return NULL;
1207 
1208 	desc = xilinx_dpdma_chan_prep_interleaved_dma(chan, xt);
1209 	if (!desc)
1210 		return NULL;
1211 
1212 	vchan_tx_prep(&chan->vchan, &desc->vdesc, flags | DMA_CTRL_ACK);
1213 
1214 	return &desc->vdesc.tx;
1215 }
1216 
1217 /**
1218  * xilinx_dpdma_alloc_chan_resources - Allocate resources for the channel
1219  * @dchan: DMA channel
1220  *
1221  * Allocate a descriptor pool for the channel.
1222  *
1223  * Return: 0 on success, or -ENOMEM if failed to allocate a pool.
1224  */
1225 static int xilinx_dpdma_alloc_chan_resources(struct dma_chan *dchan)
1226 {
1227 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1228 	size_t align = __alignof__(struct xilinx_dpdma_sw_desc);
1229 
1230 	chan->desc_pool = dma_pool_create(dev_name(chan->xdev->dev),
1231 					  chan->xdev->dev,
1232 					  sizeof(struct xilinx_dpdma_sw_desc),
1233 					  align, 0);
1234 	if (!chan->desc_pool) {
1235 		dev_err(chan->xdev->dev,
1236 			"chan%u: failed to allocate a descriptor pool\n",
1237 			chan->id);
1238 		return -ENOMEM;
1239 	}
1240 
1241 	return 0;
1242 }
1243 
1244 /**
1245  * xilinx_dpdma_free_chan_resources - Free all resources for the channel
1246  * @dchan: DMA channel
1247  *
1248  * Free resources associated with the virtual DMA channel, and destroy the
1249  * descriptor pool.
1250  */
1251 static void xilinx_dpdma_free_chan_resources(struct dma_chan *dchan)
1252 {
1253 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1254 
1255 	vchan_free_chan_resources(&chan->vchan);
1256 
1257 	dma_pool_destroy(chan->desc_pool);
1258 	chan->desc_pool = NULL;
1259 }
1260 
1261 static void xilinx_dpdma_issue_pending(struct dma_chan *dchan)
1262 {
1263 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1264 	unsigned long flags;
1265 
1266 	spin_lock_irqsave(&chan->vchan.lock, flags);
1267 	if (vchan_issue_pending(&chan->vchan))
1268 		xilinx_dpdma_chan_queue_transfer(chan);
1269 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1270 }
1271 
1272 static int xilinx_dpdma_config(struct dma_chan *dchan,
1273 			       struct dma_slave_config *config)
1274 {
1275 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1276 	unsigned long flags;
1277 
1278 	/*
1279 	 * The destination address doesn't need to be specified as the DPDMA is
1280 	 * hardwired to the destination (the DP controller). The transfer
1281 	 * width, burst size and port window size are thus meaningless, they're
1282 	 * fixed both on the DPDMA side and on the DP controller side.
1283 	 */
1284 
1285 	spin_lock_irqsave(&chan->lock, flags);
1286 
1287 	/*
1288 	 * Abuse the slave_id to indicate that the channel is part of a video
1289 	 * group.
1290 	 */
1291 	if (chan->id <= ZYNQMP_DPDMA_VIDEO2)
1292 		chan->video_group = config->slave_id != 0;
1293 
1294 	spin_unlock_irqrestore(&chan->lock, flags);
1295 
1296 	return 0;
1297 }
1298 
1299 static int xilinx_dpdma_pause(struct dma_chan *dchan)
1300 {
1301 	xilinx_dpdma_chan_pause(to_xilinx_chan(dchan));
1302 
1303 	return 0;
1304 }
1305 
1306 static int xilinx_dpdma_resume(struct dma_chan *dchan)
1307 {
1308 	xilinx_dpdma_chan_unpause(to_xilinx_chan(dchan));
1309 
1310 	return 0;
1311 }
1312 
1313 /**
1314  * xilinx_dpdma_terminate_all - Terminate the channel and descriptors
1315  * @dchan: DMA channel
1316  *
1317  * Pause the channel without waiting for ongoing transfers to complete. Waiting
1318  * for completion is performed by xilinx_dpdma_synchronize() that will disable
1319  * the channel to complete the stop.
1320  *
1321  * All the descriptors associated with the channel that are guaranteed not to
1322  * be touched by the hardware. The pending and active descriptor are not
1323  * touched, and will be freed either upon completion, or by
1324  * xilinx_dpdma_synchronize().
1325  *
1326  * Return: 0 on success, or -ETIMEDOUT if the channel failed to stop.
1327  */
1328 static int xilinx_dpdma_terminate_all(struct dma_chan *dchan)
1329 {
1330 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1331 	struct xilinx_dpdma_device *xdev = chan->xdev;
1332 	LIST_HEAD(descriptors);
1333 	unsigned long flags;
1334 	unsigned int i;
1335 
1336 	/* Pause the channel (including the whole video group if applicable). */
1337 	if (chan->video_group) {
1338 		for (i = ZYNQMP_DPDMA_VIDEO0; i <= ZYNQMP_DPDMA_VIDEO2; i++) {
1339 			if (xdev->chan[i]->video_group &&
1340 			    xdev->chan[i]->running) {
1341 				xilinx_dpdma_chan_pause(xdev->chan[i]);
1342 				xdev->chan[i]->video_group = false;
1343 			}
1344 		}
1345 	} else {
1346 		xilinx_dpdma_chan_pause(chan);
1347 	}
1348 
1349 	/* Gather all the descriptors we can free and free them. */
1350 	spin_lock_irqsave(&chan->vchan.lock, flags);
1351 	vchan_get_all_descriptors(&chan->vchan, &descriptors);
1352 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1353 
1354 	vchan_dma_desc_free_list(&chan->vchan, &descriptors);
1355 
1356 	return 0;
1357 }
1358 
1359 /**
1360  * xilinx_dpdma_synchronize - Synchronize callback execution
1361  * @dchan: DMA channel
1362  *
1363  * Synchronizing callback execution ensures that all previously issued
1364  * transfers have completed and all associated callbacks have been called and
1365  * have returned.
1366  *
1367  * This function waits for the DMA channel to stop. It assumes it has been
1368  * paused by a previous call to dmaengine_terminate_async(), and that no new
1369  * pending descriptors have been issued with dma_async_issue_pending(). The
1370  * behaviour is undefined otherwise.
1371  */
1372 static void xilinx_dpdma_synchronize(struct dma_chan *dchan)
1373 {
1374 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1375 	unsigned long flags;
1376 
1377 	xilinx_dpdma_chan_stop(chan);
1378 
1379 	spin_lock_irqsave(&chan->vchan.lock, flags);
1380 	if (chan->desc.pending) {
1381 		vchan_terminate_vdesc(&chan->desc.pending->vdesc);
1382 		chan->desc.pending = NULL;
1383 	}
1384 	if (chan->desc.active) {
1385 		vchan_terminate_vdesc(&chan->desc.active->vdesc);
1386 		chan->desc.active = NULL;
1387 	}
1388 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1389 
1390 	vchan_synchronize(&chan->vchan);
1391 }
1392 
1393 /* -----------------------------------------------------------------------------
1394  * Interrupt and Tasklet Handling
1395  */
1396 
1397 /**
1398  * xilinx_dpdma_err - Detect any global error
1399  * @isr: Interrupt Status Register
1400  * @eisr: Error Interrupt Status Register
1401  *
1402  * Return: True if any global error occurs, or false otherwise.
1403  */
1404 static bool xilinx_dpdma_err(u32 isr, u32 eisr)
1405 {
1406 	if (isr & XILINX_DPDMA_INTR_GLOBAL_ERR ||
1407 	    eisr & XILINX_DPDMA_EINTR_GLOBAL_ERR)
1408 		return true;
1409 
1410 	return false;
1411 }
1412 
1413 /**
1414  * xilinx_dpdma_handle_err_irq - Handle DPDMA error interrupt
1415  * @xdev: DPDMA device
1416  * @isr: masked Interrupt Status Register
1417  * @eisr: Error Interrupt Status Register
1418  *
1419  * Handle if any error occurs based on @isr and @eisr. This function disables
1420  * corresponding error interrupts, and those should be re-enabled once handling
1421  * is done.
1422  */
1423 static void xilinx_dpdma_handle_err_irq(struct xilinx_dpdma_device *xdev,
1424 					u32 isr, u32 eisr)
1425 {
1426 	bool err = xilinx_dpdma_err(isr, eisr);
1427 	unsigned int i;
1428 
1429 	dev_dbg_ratelimited(xdev->dev,
1430 			    "error irq: isr = 0x%08x, eisr = 0x%08x\n",
1431 			    isr, eisr);
1432 
1433 	/* Disable channel error interrupts until errors are handled. */
1434 	dpdma_write(xdev->reg, XILINX_DPDMA_IDS,
1435 		    isr & ~XILINX_DPDMA_INTR_GLOBAL_ERR);
1436 	dpdma_write(xdev->reg, XILINX_DPDMA_EIDS,
1437 		    eisr & ~XILINX_DPDMA_EINTR_GLOBAL_ERR);
1438 
1439 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1440 		if (err || xilinx_dpdma_chan_err(xdev->chan[i], isr, eisr))
1441 			tasklet_schedule(&xdev->chan[i]->err_task);
1442 }
1443 
1444 /**
1445  * xilinx_dpdma_enable_irq - Enable interrupts
1446  * @xdev: DPDMA device
1447  *
1448  * Enable interrupts.
1449  */
1450 static void xilinx_dpdma_enable_irq(struct xilinx_dpdma_device *xdev)
1451 {
1452 	dpdma_write(xdev->reg, XILINX_DPDMA_IEN, XILINX_DPDMA_INTR_ALL);
1453 	dpdma_write(xdev->reg, XILINX_DPDMA_EIEN, XILINX_DPDMA_EINTR_ALL);
1454 }
1455 
1456 /**
1457  * xilinx_dpdma_disable_irq - Disable interrupts
1458  * @xdev: DPDMA device
1459  *
1460  * Disable interrupts.
1461  */
1462 static void xilinx_dpdma_disable_irq(struct xilinx_dpdma_device *xdev)
1463 {
1464 	dpdma_write(xdev->reg, XILINX_DPDMA_IDS, XILINX_DPDMA_INTR_ALL);
1465 	dpdma_write(xdev->reg, XILINX_DPDMA_EIDS, XILINX_DPDMA_EINTR_ALL);
1466 }
1467 
1468 /**
1469  * xilinx_dpdma_chan_err_task - Per channel tasklet for error handling
1470  * @t: pointer to the tasklet associated with this handler
1471  *
1472  * Per channel error handling tasklet. This function waits for the outstanding
1473  * transaction to complete and triggers error handling. After error handling,
1474  * re-enable channel error interrupts, and restart the channel if needed.
1475  */
1476 static void xilinx_dpdma_chan_err_task(struct tasklet_struct *t)
1477 {
1478 	struct xilinx_dpdma_chan *chan = from_tasklet(chan, t, err_task);
1479 	struct xilinx_dpdma_device *xdev = chan->xdev;
1480 	unsigned long flags;
1481 
1482 	/* Proceed error handling even when polling fails. */
1483 	xilinx_dpdma_chan_poll_no_ostand(chan);
1484 
1485 	xilinx_dpdma_chan_handle_err(chan);
1486 
1487 	dpdma_write(xdev->reg, XILINX_DPDMA_IEN,
1488 		    XILINX_DPDMA_INTR_CHAN_ERR_MASK << chan->id);
1489 	dpdma_write(xdev->reg, XILINX_DPDMA_EIEN,
1490 		    XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id);
1491 
1492 	spin_lock_irqsave(&chan->lock, flags);
1493 	xilinx_dpdma_chan_queue_transfer(chan);
1494 	spin_unlock_irqrestore(&chan->lock, flags);
1495 }
1496 
1497 static irqreturn_t xilinx_dpdma_irq_handler(int irq, void *data)
1498 {
1499 	struct xilinx_dpdma_device *xdev = data;
1500 	unsigned long mask;
1501 	unsigned int i;
1502 	u32 status;
1503 	u32 error;
1504 
1505 	status = dpdma_read(xdev->reg, XILINX_DPDMA_ISR);
1506 	error = dpdma_read(xdev->reg, XILINX_DPDMA_EISR);
1507 	if (!status && !error)
1508 		return IRQ_NONE;
1509 
1510 	dpdma_write(xdev->reg, XILINX_DPDMA_ISR, status);
1511 	dpdma_write(xdev->reg, XILINX_DPDMA_EISR, error);
1512 
1513 	if (status & XILINX_DPDMA_INTR_VSYNC) {
1514 		/*
1515 		 * There's a single VSYNC interrupt that needs to be processed
1516 		 * by each running channel to update the active descriptor.
1517 		 */
1518 		for (i = 0; i < ARRAY_SIZE(xdev->chan); i++) {
1519 			struct xilinx_dpdma_chan *chan = xdev->chan[i];
1520 
1521 			if (chan)
1522 				xilinx_dpdma_chan_vsync_irq(chan);
1523 		}
1524 	}
1525 
1526 	mask = FIELD_GET(XILINX_DPDMA_INTR_DESC_DONE_MASK, status);
1527 	if (mask) {
1528 		for_each_set_bit(i, &mask, ARRAY_SIZE(xdev->chan))
1529 			xilinx_dpdma_chan_done_irq(xdev->chan[i]);
1530 	}
1531 
1532 	mask = FIELD_GET(XILINX_DPDMA_INTR_NO_OSTAND_MASK, status);
1533 	if (mask) {
1534 		for_each_set_bit(i, &mask, ARRAY_SIZE(xdev->chan))
1535 			xilinx_dpdma_chan_notify_no_ostand(xdev->chan[i]);
1536 	}
1537 
1538 	mask = status & XILINX_DPDMA_INTR_ERR_ALL;
1539 	if (mask || error)
1540 		xilinx_dpdma_handle_err_irq(xdev, mask, error);
1541 
1542 	return IRQ_HANDLED;
1543 }
1544 
1545 /* -----------------------------------------------------------------------------
1546  * Initialization & Cleanup
1547  */
1548 
1549 static int xilinx_dpdma_chan_init(struct xilinx_dpdma_device *xdev,
1550 				  unsigned int chan_id)
1551 {
1552 	struct xilinx_dpdma_chan *chan;
1553 
1554 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
1555 	if (!chan)
1556 		return -ENOMEM;
1557 
1558 	chan->id = chan_id;
1559 	chan->reg = xdev->reg + XILINX_DPDMA_CH_BASE
1560 		  + XILINX_DPDMA_CH_OFFSET * chan->id;
1561 	chan->running = false;
1562 	chan->xdev = xdev;
1563 
1564 	spin_lock_init(&chan->lock);
1565 	init_waitqueue_head(&chan->wait_to_stop);
1566 
1567 	tasklet_setup(&chan->err_task, xilinx_dpdma_chan_err_task);
1568 
1569 	chan->vchan.desc_free = xilinx_dpdma_chan_free_tx_desc;
1570 	vchan_init(&chan->vchan, &xdev->common);
1571 
1572 	xdev->chan[chan->id] = chan;
1573 
1574 	return 0;
1575 }
1576 
1577 static void xilinx_dpdma_chan_remove(struct xilinx_dpdma_chan *chan)
1578 {
1579 	if (!chan)
1580 		return;
1581 
1582 	tasklet_kill(&chan->err_task);
1583 	list_del(&chan->vchan.chan.device_node);
1584 }
1585 
1586 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
1587 					    struct of_dma *ofdma)
1588 {
1589 	struct xilinx_dpdma_device *xdev = ofdma->of_dma_data;
1590 	u32 chan_id = dma_spec->args[0];
1591 
1592 	if (chan_id >= ARRAY_SIZE(xdev->chan))
1593 		return NULL;
1594 
1595 	if (!xdev->chan[chan_id])
1596 		return NULL;
1597 
1598 	return dma_get_slave_channel(&xdev->chan[chan_id]->vchan.chan);
1599 }
1600 
1601 static void dpdma_hw_init(struct xilinx_dpdma_device *xdev)
1602 {
1603 	unsigned int i;
1604 	void __iomem *reg;
1605 
1606 	/* Disable all interrupts */
1607 	xilinx_dpdma_disable_irq(xdev);
1608 
1609 	/* Stop all channels */
1610 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++) {
1611 		reg = xdev->reg + XILINX_DPDMA_CH_BASE
1612 				+ XILINX_DPDMA_CH_OFFSET * i;
1613 		dpdma_clr(reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_ENABLE);
1614 	}
1615 
1616 	/* Clear the interrupt status registers */
1617 	dpdma_write(xdev->reg, XILINX_DPDMA_ISR, XILINX_DPDMA_INTR_ALL);
1618 	dpdma_write(xdev->reg, XILINX_DPDMA_EISR, XILINX_DPDMA_EINTR_ALL);
1619 }
1620 
1621 static int xilinx_dpdma_probe(struct platform_device *pdev)
1622 {
1623 	struct xilinx_dpdma_device *xdev;
1624 	struct dma_device *ddev;
1625 	unsigned int i;
1626 	int ret;
1627 
1628 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
1629 	if (!xdev)
1630 		return -ENOMEM;
1631 
1632 	xdev->dev = &pdev->dev;
1633 	xdev->ext_addr = sizeof(dma_addr_t) > 4;
1634 
1635 	INIT_LIST_HEAD(&xdev->common.channels);
1636 
1637 	platform_set_drvdata(pdev, xdev);
1638 
1639 	xdev->axi_clk = devm_clk_get(xdev->dev, "axi_clk");
1640 	if (IS_ERR(xdev->axi_clk))
1641 		return PTR_ERR(xdev->axi_clk);
1642 
1643 	xdev->reg = devm_platform_ioremap_resource(pdev, 0);
1644 	if (IS_ERR(xdev->reg))
1645 		return PTR_ERR(xdev->reg);
1646 
1647 	dpdma_hw_init(xdev);
1648 
1649 	xdev->irq = platform_get_irq(pdev, 0);
1650 	if (xdev->irq < 0) {
1651 		dev_err(xdev->dev, "failed to get platform irq\n");
1652 		return xdev->irq;
1653 	}
1654 
1655 	ret = request_irq(xdev->irq, xilinx_dpdma_irq_handler, IRQF_SHARED,
1656 			  dev_name(xdev->dev), xdev);
1657 	if (ret) {
1658 		dev_err(xdev->dev, "failed to request IRQ\n");
1659 		return ret;
1660 	}
1661 
1662 	ddev = &xdev->common;
1663 	ddev->dev = &pdev->dev;
1664 
1665 	dma_cap_set(DMA_SLAVE, ddev->cap_mask);
1666 	dma_cap_set(DMA_PRIVATE, ddev->cap_mask);
1667 	dma_cap_set(DMA_INTERLEAVE, ddev->cap_mask);
1668 	dma_cap_set(DMA_REPEAT, ddev->cap_mask);
1669 	dma_cap_set(DMA_LOAD_EOT, ddev->cap_mask);
1670 	ddev->copy_align = fls(XILINX_DPDMA_ALIGN_BYTES - 1);
1671 
1672 	ddev->device_alloc_chan_resources = xilinx_dpdma_alloc_chan_resources;
1673 	ddev->device_free_chan_resources = xilinx_dpdma_free_chan_resources;
1674 	ddev->device_prep_interleaved_dma = xilinx_dpdma_prep_interleaved_dma;
1675 	/* TODO: Can we achieve better granularity ? */
1676 	ddev->device_tx_status = dma_cookie_status;
1677 	ddev->device_issue_pending = xilinx_dpdma_issue_pending;
1678 	ddev->device_config = xilinx_dpdma_config;
1679 	ddev->device_pause = xilinx_dpdma_pause;
1680 	ddev->device_resume = xilinx_dpdma_resume;
1681 	ddev->device_terminate_all = xilinx_dpdma_terminate_all;
1682 	ddev->device_synchronize = xilinx_dpdma_synchronize;
1683 	ddev->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED);
1684 	ddev->directions = BIT(DMA_MEM_TO_DEV);
1685 	ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1686 
1687 	for (i = 0; i < ARRAY_SIZE(xdev->chan); ++i) {
1688 		ret = xilinx_dpdma_chan_init(xdev, i);
1689 		if (ret < 0) {
1690 			dev_err(xdev->dev, "failed to initialize channel %u\n",
1691 				i);
1692 			goto error;
1693 		}
1694 	}
1695 
1696 	ret = clk_prepare_enable(xdev->axi_clk);
1697 	if (ret) {
1698 		dev_err(xdev->dev, "failed to enable the axi clock\n");
1699 		goto error;
1700 	}
1701 
1702 	ret = dma_async_device_register(ddev);
1703 	if (ret) {
1704 		dev_err(xdev->dev, "failed to register the dma device\n");
1705 		goto error_dma_async;
1706 	}
1707 
1708 	ret = of_dma_controller_register(xdev->dev->of_node,
1709 					 of_dma_xilinx_xlate, ddev);
1710 	if (ret) {
1711 		dev_err(xdev->dev, "failed to register DMA to DT DMA helper\n");
1712 		goto error_of_dma;
1713 	}
1714 
1715 	xilinx_dpdma_enable_irq(xdev);
1716 
1717 	xilinx_dpdma_debugfs_init(xdev);
1718 
1719 	dev_info(&pdev->dev, "Xilinx DPDMA engine is probed\n");
1720 
1721 	return 0;
1722 
1723 error_of_dma:
1724 	dma_async_device_unregister(ddev);
1725 error_dma_async:
1726 	clk_disable_unprepare(xdev->axi_clk);
1727 error:
1728 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1729 		xilinx_dpdma_chan_remove(xdev->chan[i]);
1730 
1731 	free_irq(xdev->irq, xdev);
1732 
1733 	return ret;
1734 }
1735 
1736 static int xilinx_dpdma_remove(struct platform_device *pdev)
1737 {
1738 	struct xilinx_dpdma_device *xdev = platform_get_drvdata(pdev);
1739 	unsigned int i;
1740 
1741 	/* Start by disabling the IRQ to avoid races during cleanup. */
1742 	free_irq(xdev->irq, xdev);
1743 
1744 	xilinx_dpdma_disable_irq(xdev);
1745 	of_dma_controller_free(pdev->dev.of_node);
1746 	dma_async_device_unregister(&xdev->common);
1747 	clk_disable_unprepare(xdev->axi_clk);
1748 
1749 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1750 		xilinx_dpdma_chan_remove(xdev->chan[i]);
1751 
1752 	return 0;
1753 }
1754 
1755 static const struct of_device_id xilinx_dpdma_of_match[] = {
1756 	{ .compatible = "xlnx,zynqmp-dpdma",},
1757 	{ /* end of table */ },
1758 };
1759 MODULE_DEVICE_TABLE(of, xilinx_dpdma_of_match);
1760 
1761 static struct platform_driver xilinx_dpdma_driver = {
1762 	.probe			= xilinx_dpdma_probe,
1763 	.remove			= xilinx_dpdma_remove,
1764 	.driver			= {
1765 		.name		= "xilinx-zynqmp-dpdma",
1766 		.of_match_table	= xilinx_dpdma_of_match,
1767 	},
1768 };
1769 
1770 module_platform_driver(xilinx_dpdma_driver);
1771 
1772 MODULE_AUTHOR("Xilinx, Inc.");
1773 MODULE_DESCRIPTION("Xilinx ZynqMP DPDMA driver");
1774 MODULE_LICENSE("GPL v2");
1775