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 
275 #ifdef CONFIG_DEBUG_FS
276 
277 #define XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE	32
278 #define XILINX_DPDMA_DEBUGFS_UINT16_MAX_STR	"65535"
279 
280 /* Match xilinx_dpdma_testcases vs dpdma_debugfs_reqs[] entry */
281 enum xilinx_dpdma_testcases {
282 	DPDMA_TC_INTR_DONE,
283 	DPDMA_TC_NONE
284 };
285 
286 struct xilinx_dpdma_debugfs {
287 	enum xilinx_dpdma_testcases testcase;
288 	u16 xilinx_dpdma_irq_done_count;
289 	unsigned int chan_id;
290 };
291 
292 static struct xilinx_dpdma_debugfs dpdma_debugfs;
293 struct xilinx_dpdma_debugfs_request {
294 	const char *name;
295 	enum xilinx_dpdma_testcases tc;
296 	ssize_t (*read)(char *buf);
297 	int (*write)(char *args);
298 };
299 
300 static void xilinx_dpdma_debugfs_desc_done_irq(struct xilinx_dpdma_chan *chan)
301 {
302 	if (chan->id == dpdma_debugfs.chan_id)
303 		dpdma_debugfs.xilinx_dpdma_irq_done_count++;
304 }
305 
306 static ssize_t xilinx_dpdma_debugfs_desc_done_irq_read(char *buf)
307 {
308 	size_t out_str_len;
309 
310 	dpdma_debugfs.testcase = DPDMA_TC_NONE;
311 
312 	out_str_len = strlen(XILINX_DPDMA_DEBUGFS_UINT16_MAX_STR);
313 	out_str_len = min_t(size_t, XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE,
314 			    out_str_len);
315 	snprintf(buf, out_str_len, "%d",
316 		 dpdma_debugfs.xilinx_dpdma_irq_done_count);
317 
318 	return 0;
319 }
320 
321 static int xilinx_dpdma_debugfs_desc_done_irq_write(char *args)
322 {
323 	char *arg;
324 	int ret;
325 	u32 id;
326 
327 	arg = strsep(&args, " ");
328 	if (!arg || strncasecmp(arg, "start", 5))
329 		return -EINVAL;
330 
331 	arg = strsep(&args, " ");
332 	if (!arg)
333 		return -EINVAL;
334 
335 	ret = kstrtou32(arg, 0, &id);
336 	if (ret < 0)
337 		return ret;
338 
339 	if (id < ZYNQMP_DPDMA_VIDEO0 || id > ZYNQMP_DPDMA_AUDIO1)
340 		return -EINVAL;
341 
342 	dpdma_debugfs.testcase = DPDMA_TC_INTR_DONE;
343 	dpdma_debugfs.xilinx_dpdma_irq_done_count = 0;
344 	dpdma_debugfs.chan_id = id;
345 
346 	return 0;
347 }
348 
349 /* Match xilinx_dpdma_testcases vs dpdma_debugfs_reqs[] entry */
350 static struct xilinx_dpdma_debugfs_request dpdma_debugfs_reqs[] = {
351 	{
352 		.name = "DESCRIPTOR_DONE_INTR",
353 		.tc = DPDMA_TC_INTR_DONE,
354 		.read = xilinx_dpdma_debugfs_desc_done_irq_read,
355 		.write = xilinx_dpdma_debugfs_desc_done_irq_write,
356 	},
357 };
358 
359 static ssize_t xilinx_dpdma_debugfs_read(struct file *f, char __user *buf,
360 					 size_t size, loff_t *pos)
361 {
362 	enum xilinx_dpdma_testcases testcase;
363 	char *kern_buff;
364 	int ret = 0;
365 
366 	if (*pos != 0 || size <= 0)
367 		return -EINVAL;
368 
369 	kern_buff = kzalloc(XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE, GFP_KERNEL);
370 	if (!kern_buff) {
371 		dpdma_debugfs.testcase = DPDMA_TC_NONE;
372 		return -ENOMEM;
373 	}
374 
375 	testcase = READ_ONCE(dpdma_debugfs.testcase);
376 	if (testcase != DPDMA_TC_NONE) {
377 		ret = dpdma_debugfs_reqs[testcase].read(kern_buff);
378 		if (ret < 0)
379 			goto done;
380 	} else {
381 		strlcpy(kern_buff, "No testcase executed",
382 			XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE);
383 	}
384 
385 	size = min(size, strlen(kern_buff));
386 	if (copy_to_user(buf, kern_buff, size))
387 		ret = -EFAULT;
388 
389 done:
390 	kfree(kern_buff);
391 	if (ret)
392 		return ret;
393 
394 	*pos = size + 1;
395 	return size;
396 }
397 
398 static ssize_t xilinx_dpdma_debugfs_write(struct file *f,
399 					  const char __user *buf, size_t size,
400 					  loff_t *pos)
401 {
402 	char *kern_buff, *kern_buff_start;
403 	char *testcase;
404 	unsigned int i;
405 	int ret;
406 
407 	if (*pos != 0 || size <= 0)
408 		return -EINVAL;
409 
410 	/* Supporting single instance of test as of now. */
411 	if (dpdma_debugfs.testcase != DPDMA_TC_NONE)
412 		return -EBUSY;
413 
414 	kern_buff = kzalloc(size, GFP_KERNEL);
415 	if (!kern_buff)
416 		return -ENOMEM;
417 	kern_buff_start = kern_buff;
418 
419 	ret = strncpy_from_user(kern_buff, buf, size);
420 	if (ret < 0)
421 		goto done;
422 
423 	/* Read the testcase name from a user request. */
424 	testcase = strsep(&kern_buff, " ");
425 
426 	for (i = 0; i < ARRAY_SIZE(dpdma_debugfs_reqs); i++) {
427 		if (!strcasecmp(testcase, dpdma_debugfs_reqs[i].name))
428 			break;
429 	}
430 
431 	if (i == ARRAY_SIZE(dpdma_debugfs_reqs)) {
432 		ret = -EINVAL;
433 		goto done;
434 	}
435 
436 	ret = dpdma_debugfs_reqs[i].write(kern_buff);
437 	if (ret < 0)
438 		goto done;
439 
440 	ret = size;
441 
442 done:
443 	kfree(kern_buff_start);
444 	return ret;
445 }
446 
447 static const struct file_operations fops_xilinx_dpdma_dbgfs = {
448 	.owner = THIS_MODULE,
449 	.read = xilinx_dpdma_debugfs_read,
450 	.write = xilinx_dpdma_debugfs_write,
451 };
452 
453 static void xilinx_dpdma_debugfs_init(struct xilinx_dpdma_device *xdev)
454 {
455 	struct dentry *dent;
456 
457 	dpdma_debugfs.testcase = DPDMA_TC_NONE;
458 
459 	dent = debugfs_create_file("testcase", 0444, xdev->common.dbg_dev_root,
460 				   NULL, &fops_xilinx_dpdma_dbgfs);
461 	if (IS_ERR(dent))
462 		dev_err(xdev->dev, "Failed to create debugfs testcase file\n");
463 }
464 
465 #else
466 static void xilinx_dpdma_debugfs_init(struct xilinx_dpdma_device *xdev)
467 {
468 }
469 
470 static void xilinx_dpdma_debugfs_desc_done_irq(struct xilinx_dpdma_chan *chan)
471 {
472 }
473 #endif /* CONFIG_DEBUG_FS */
474 
475 /* -----------------------------------------------------------------------------
476  * I/O Accessors
477  */
478 
479 static inline u32 dpdma_read(void __iomem *base, u32 offset)
480 {
481 	return ioread32(base + offset);
482 }
483 
484 static inline void dpdma_write(void __iomem *base, u32 offset, u32 val)
485 {
486 	iowrite32(val, base + offset);
487 }
488 
489 static inline void dpdma_clr(void __iomem *base, u32 offset, u32 clr)
490 {
491 	dpdma_write(base, offset, dpdma_read(base, offset) & ~clr);
492 }
493 
494 static inline void dpdma_set(void __iomem *base, u32 offset, u32 set)
495 {
496 	dpdma_write(base, offset, dpdma_read(base, offset) | set);
497 }
498 
499 /* -----------------------------------------------------------------------------
500  * Descriptor Operations
501  */
502 
503 /**
504  * xilinx_dpdma_sw_desc_set_dma_addrs - Set DMA addresses in the descriptor
505  * @xdev: DPDMA device
506  * @sw_desc: The software descriptor in which to set DMA addresses
507  * @prev: The previous descriptor
508  * @dma_addr: array of dma addresses
509  * @num_src_addr: number of addresses in @dma_addr
510  *
511  * Set all the DMA addresses in the hardware descriptor corresponding to @dev
512  * from @dma_addr. If a previous descriptor is specified in @prev, its next
513  * descriptor DMA address is set to the DMA address of @sw_desc. @prev may be
514  * identical to @sw_desc for cyclic transfers.
515  */
516 static void xilinx_dpdma_sw_desc_set_dma_addrs(struct xilinx_dpdma_device *xdev,
517 					       struct xilinx_dpdma_sw_desc *sw_desc,
518 					       struct xilinx_dpdma_sw_desc *prev,
519 					       dma_addr_t dma_addr[],
520 					       unsigned int num_src_addr)
521 {
522 	struct xilinx_dpdma_hw_desc *hw_desc = &sw_desc->hw;
523 	unsigned int i;
524 
525 	hw_desc->src_addr = lower_32_bits(dma_addr[0]);
526 	if (xdev->ext_addr)
527 		hw_desc->addr_ext |=
528 			FIELD_PREP(XILINX_DPDMA_DESC_ADDR_EXT_SRC_ADDR_MASK,
529 				   upper_32_bits(dma_addr[0]));
530 
531 	for (i = 1; i < num_src_addr; i++) {
532 		u32 *addr = &hw_desc->src_addr2;
533 
534 		addr[i - 1] = lower_32_bits(dma_addr[i]);
535 
536 		if (xdev->ext_addr) {
537 			u32 *addr_ext = &hw_desc->addr_ext_23;
538 			u32 addr_msb;
539 
540 			addr_msb = upper_32_bits(dma_addr[i]) & GENMASK(15, 0);
541 			addr_msb <<= 16 * ((i - 1) % 2);
542 			addr_ext[(i - 1) / 2] |= addr_msb;
543 		}
544 	}
545 
546 	if (!prev)
547 		return;
548 
549 	prev->hw.next_desc = lower_32_bits(sw_desc->dma_addr);
550 	if (xdev->ext_addr)
551 		prev->hw.addr_ext |=
552 			FIELD_PREP(XILINX_DPDMA_DESC_ADDR_EXT_NEXT_ADDR_MASK,
553 				   upper_32_bits(sw_desc->dma_addr));
554 }
555 
556 /**
557  * xilinx_dpdma_chan_alloc_sw_desc - Allocate a software descriptor
558  * @chan: DPDMA channel
559  *
560  * Allocate a software descriptor from the channel's descriptor pool.
561  *
562  * Return: a software descriptor or NULL.
563  */
564 static struct xilinx_dpdma_sw_desc *
565 xilinx_dpdma_chan_alloc_sw_desc(struct xilinx_dpdma_chan *chan)
566 {
567 	struct xilinx_dpdma_sw_desc *sw_desc;
568 	dma_addr_t dma_addr;
569 
570 	sw_desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &dma_addr);
571 	if (!sw_desc)
572 		return NULL;
573 
574 	sw_desc->dma_addr = dma_addr;
575 
576 	return sw_desc;
577 }
578 
579 /**
580  * xilinx_dpdma_chan_free_sw_desc - Free a software descriptor
581  * @chan: DPDMA channel
582  * @sw_desc: software descriptor to free
583  *
584  * Free a software descriptor from the channel's descriptor pool.
585  */
586 static void
587 xilinx_dpdma_chan_free_sw_desc(struct xilinx_dpdma_chan *chan,
588 			       struct xilinx_dpdma_sw_desc *sw_desc)
589 {
590 	dma_pool_free(chan->desc_pool, sw_desc, sw_desc->dma_addr);
591 }
592 
593 /**
594  * xilinx_dpdma_chan_dump_tx_desc - Dump a tx descriptor
595  * @chan: DPDMA channel
596  * @tx_desc: tx descriptor to dump
597  *
598  * Dump contents of a tx descriptor
599  */
600 static void xilinx_dpdma_chan_dump_tx_desc(struct xilinx_dpdma_chan *chan,
601 					   struct xilinx_dpdma_tx_desc *tx_desc)
602 {
603 	struct xilinx_dpdma_sw_desc *sw_desc;
604 	struct device *dev = chan->xdev->dev;
605 	unsigned int i = 0;
606 
607 	dev_dbg(dev, "------- TX descriptor dump start -------\n");
608 	dev_dbg(dev, "------- channel ID = %d -------\n", chan->id);
609 
610 	list_for_each_entry(sw_desc, &tx_desc->descriptors, node) {
611 		struct xilinx_dpdma_hw_desc *hw_desc = &sw_desc->hw;
612 
613 		dev_dbg(dev, "------- HW descriptor %d -------\n", i++);
614 		dev_dbg(dev, "descriptor DMA addr: %pad\n", &sw_desc->dma_addr);
615 		dev_dbg(dev, "control: 0x%08x\n", hw_desc->control);
616 		dev_dbg(dev, "desc_id: 0x%08x\n", hw_desc->desc_id);
617 		dev_dbg(dev, "xfer_size: 0x%08x\n", hw_desc->xfer_size);
618 		dev_dbg(dev, "hsize_stride: 0x%08x\n", hw_desc->hsize_stride);
619 		dev_dbg(dev, "timestamp_lsb: 0x%08x\n", hw_desc->timestamp_lsb);
620 		dev_dbg(dev, "timestamp_msb: 0x%08x\n", hw_desc->timestamp_msb);
621 		dev_dbg(dev, "addr_ext: 0x%08x\n", hw_desc->addr_ext);
622 		dev_dbg(dev, "next_desc: 0x%08x\n", hw_desc->next_desc);
623 		dev_dbg(dev, "src_addr: 0x%08x\n", hw_desc->src_addr);
624 		dev_dbg(dev, "addr_ext_23: 0x%08x\n", hw_desc->addr_ext_23);
625 		dev_dbg(dev, "addr_ext_45: 0x%08x\n", hw_desc->addr_ext_45);
626 		dev_dbg(dev, "src_addr2: 0x%08x\n", hw_desc->src_addr2);
627 		dev_dbg(dev, "src_addr3: 0x%08x\n", hw_desc->src_addr3);
628 		dev_dbg(dev, "src_addr4: 0x%08x\n", hw_desc->src_addr4);
629 		dev_dbg(dev, "src_addr5: 0x%08x\n", hw_desc->src_addr5);
630 		dev_dbg(dev, "crc: 0x%08x\n", hw_desc->crc);
631 	}
632 
633 	dev_dbg(dev, "------- TX descriptor dump end -------\n");
634 }
635 
636 /**
637  * xilinx_dpdma_chan_alloc_tx_desc - Allocate a transaction descriptor
638  * @chan: DPDMA channel
639  *
640  * Allocate a tx descriptor.
641  *
642  * Return: a tx descriptor or NULL.
643  */
644 static struct xilinx_dpdma_tx_desc *
645 xilinx_dpdma_chan_alloc_tx_desc(struct xilinx_dpdma_chan *chan)
646 {
647 	struct xilinx_dpdma_tx_desc *tx_desc;
648 
649 	tx_desc = kzalloc(sizeof(*tx_desc), GFP_NOWAIT);
650 	if (!tx_desc)
651 		return NULL;
652 
653 	INIT_LIST_HEAD(&tx_desc->descriptors);
654 	tx_desc->chan = chan;
655 	tx_desc->error = false;
656 
657 	return tx_desc;
658 }
659 
660 /**
661  * xilinx_dpdma_chan_free_tx_desc - Free a virtual DMA descriptor
662  * @vdesc: virtual DMA descriptor
663  *
664  * Free the virtual DMA descriptor @vdesc including its software descriptors.
665  */
666 static void xilinx_dpdma_chan_free_tx_desc(struct virt_dma_desc *vdesc)
667 {
668 	struct xilinx_dpdma_sw_desc *sw_desc, *next;
669 	struct xilinx_dpdma_tx_desc *desc;
670 
671 	if (!vdesc)
672 		return;
673 
674 	desc = to_dpdma_tx_desc(vdesc);
675 
676 	list_for_each_entry_safe(sw_desc, next, &desc->descriptors, node) {
677 		list_del(&sw_desc->node);
678 		xilinx_dpdma_chan_free_sw_desc(desc->chan, sw_desc);
679 	}
680 
681 	kfree(desc);
682 }
683 
684 /**
685  * xilinx_dpdma_chan_prep_interleaved_dma - Prepare an interleaved dma
686  *					    descriptor
687  * @chan: DPDMA channel
688  * @xt: dma interleaved template
689  *
690  * Prepare a tx descriptor including internal software/hardware descriptors
691  * based on @xt.
692  *
693  * Return: A DPDMA TX descriptor on success, or NULL.
694  */
695 static struct xilinx_dpdma_tx_desc *
696 xilinx_dpdma_chan_prep_interleaved_dma(struct xilinx_dpdma_chan *chan,
697 				       struct dma_interleaved_template *xt)
698 {
699 	struct xilinx_dpdma_tx_desc *tx_desc;
700 	struct xilinx_dpdma_sw_desc *sw_desc;
701 	struct xilinx_dpdma_hw_desc *hw_desc;
702 	size_t hsize = xt->sgl[0].size;
703 	size_t stride = hsize + xt->sgl[0].icg;
704 
705 	if (!IS_ALIGNED(xt->src_start, XILINX_DPDMA_ALIGN_BYTES)) {
706 		dev_err(chan->xdev->dev,
707 			"chan%u: buffer should be aligned at %d B\n",
708 			chan->id, XILINX_DPDMA_ALIGN_BYTES);
709 		return NULL;
710 	}
711 
712 	tx_desc = xilinx_dpdma_chan_alloc_tx_desc(chan);
713 	if (!tx_desc)
714 		return NULL;
715 
716 	sw_desc = xilinx_dpdma_chan_alloc_sw_desc(chan);
717 	if (!sw_desc) {
718 		xilinx_dpdma_chan_free_tx_desc(&tx_desc->vdesc);
719 		return NULL;
720 	}
721 
722 	xilinx_dpdma_sw_desc_set_dma_addrs(chan->xdev, sw_desc, sw_desc,
723 					   &xt->src_start, 1);
724 
725 	hw_desc = &sw_desc->hw;
726 	hsize = ALIGN(hsize, XILINX_DPDMA_LINESIZE_ALIGN_BITS / 8);
727 	hw_desc->xfer_size = hsize * xt->numf;
728 	hw_desc->hsize_stride =
729 		FIELD_PREP(XILINX_DPDMA_DESC_HSIZE_STRIDE_HSIZE_MASK, hsize) |
730 		FIELD_PREP(XILINX_DPDMA_DESC_HSIZE_STRIDE_STRIDE_MASK,
731 			   stride / 16);
732 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_PREEMBLE;
733 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_COMPLETE_INTR;
734 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_IGNORE_DONE;
735 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_LAST_OF_FRAME;
736 
737 	list_add_tail(&sw_desc->node, &tx_desc->descriptors);
738 
739 	return tx_desc;
740 }
741 
742 /* -----------------------------------------------------------------------------
743  * DPDMA Channel Operations
744  */
745 
746 /**
747  * xilinx_dpdma_chan_enable - Enable the channel
748  * @chan: DPDMA channel
749  *
750  * Enable the channel and its interrupts. Set the QoS values for video class.
751  */
752 static void xilinx_dpdma_chan_enable(struct xilinx_dpdma_chan *chan)
753 {
754 	u32 reg;
755 
756 	reg = (XILINX_DPDMA_INTR_CHAN_MASK << chan->id)
757 	    | XILINX_DPDMA_INTR_GLOBAL_MASK;
758 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN, reg);
759 	reg = (XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id)
760 	    | XILINX_DPDMA_INTR_GLOBAL_ERR;
761 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_EIEN, reg);
762 
763 	reg = XILINX_DPDMA_CH_CNTL_ENABLE
764 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DSCR_WR_MASK,
765 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS)
766 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DSCR_RD_MASK,
767 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS)
768 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DATA_RD_MASK,
769 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS);
770 	dpdma_set(chan->reg, XILINX_DPDMA_CH_CNTL, reg);
771 }
772 
773 /**
774  * xilinx_dpdma_chan_disable - Disable the channel
775  * @chan: DPDMA channel
776  *
777  * Disable the channel and its interrupts.
778  */
779 static void xilinx_dpdma_chan_disable(struct xilinx_dpdma_chan *chan)
780 {
781 	u32 reg;
782 
783 	reg = XILINX_DPDMA_INTR_CHAN_MASK << chan->id;
784 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN, reg);
785 	reg = XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id;
786 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_EIEN, reg);
787 
788 	dpdma_clr(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_ENABLE);
789 }
790 
791 /**
792  * xilinx_dpdma_chan_pause - Pause the channel
793  * @chan: DPDMA channel
794  *
795  * Pause the channel.
796  */
797 static void xilinx_dpdma_chan_pause(struct xilinx_dpdma_chan *chan)
798 {
799 	dpdma_set(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_PAUSE);
800 }
801 
802 /**
803  * xilinx_dpdma_chan_unpause - Unpause the channel
804  * @chan: DPDMA channel
805  *
806  * Unpause the channel.
807  */
808 static void xilinx_dpdma_chan_unpause(struct xilinx_dpdma_chan *chan)
809 {
810 	dpdma_clr(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_PAUSE);
811 }
812 
813 static u32 xilinx_dpdma_chan_video_group_ready(struct xilinx_dpdma_chan *chan)
814 {
815 	struct xilinx_dpdma_device *xdev = chan->xdev;
816 	u32 channels = 0;
817 	unsigned int i;
818 
819 	for (i = ZYNQMP_DPDMA_VIDEO0; i <= ZYNQMP_DPDMA_VIDEO2; i++) {
820 		if (xdev->chan[i]->video_group && !xdev->chan[i]->running)
821 			return 0;
822 
823 		if (xdev->chan[i]->video_group)
824 			channels |= BIT(i);
825 	}
826 
827 	return channels;
828 }
829 
830 /**
831  * xilinx_dpdma_chan_queue_transfer - Queue the next transfer
832  * @chan: DPDMA channel
833  *
834  * Queue the next descriptor, if any, to the hardware. If the channel is
835  * stopped, start it first. Otherwise retrigger it with the next descriptor.
836  */
837 static void xilinx_dpdma_chan_queue_transfer(struct xilinx_dpdma_chan *chan)
838 {
839 	struct xilinx_dpdma_device *xdev = chan->xdev;
840 	struct xilinx_dpdma_sw_desc *sw_desc;
841 	struct xilinx_dpdma_tx_desc *desc;
842 	struct virt_dma_desc *vdesc;
843 	u32 reg, channels;
844 	bool first_frame;
845 
846 	lockdep_assert_held(&chan->lock);
847 
848 	if (chan->desc.pending)
849 		return;
850 
851 	if (!chan->running) {
852 		xilinx_dpdma_chan_unpause(chan);
853 		xilinx_dpdma_chan_enable(chan);
854 		chan->first_frame = true;
855 		chan->running = true;
856 	}
857 
858 	vdesc = vchan_next_desc(&chan->vchan);
859 	if (!vdesc)
860 		return;
861 
862 	desc = to_dpdma_tx_desc(vdesc);
863 	chan->desc.pending = desc;
864 	list_del(&desc->vdesc.node);
865 
866 	/*
867 	 * Assign the cookie to descriptors in this transaction. Only 16 bit
868 	 * will be used, but it should be enough.
869 	 */
870 	list_for_each_entry(sw_desc, &desc->descriptors, node)
871 		sw_desc->hw.desc_id = desc->vdesc.tx.cookie
872 				    & XILINX_DPDMA_CH_DESC_ID_MASK;
873 
874 	sw_desc = list_first_entry(&desc->descriptors,
875 				   struct xilinx_dpdma_sw_desc, node);
876 	dpdma_write(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDR,
877 		    lower_32_bits(sw_desc->dma_addr));
878 	if (xdev->ext_addr)
879 		dpdma_write(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDRE,
880 			    FIELD_PREP(XILINX_DPDMA_CH_DESC_START_ADDRE_MASK,
881 				       upper_32_bits(sw_desc->dma_addr)));
882 
883 	first_frame = chan->first_frame;
884 	chan->first_frame = false;
885 
886 	if (chan->video_group) {
887 		channels = xilinx_dpdma_chan_video_group_ready(chan);
888 		/*
889 		 * Trigger the transfer only when all channels in the group are
890 		 * ready.
891 		 */
892 		if (!channels)
893 			return;
894 	} else {
895 		channels = BIT(chan->id);
896 	}
897 
898 	if (first_frame)
899 		reg = XILINX_DPDMA_GBL_TRIG_MASK(channels);
900 	else
901 		reg = XILINX_DPDMA_GBL_RETRIG_MASK(channels);
902 
903 	dpdma_write(xdev->reg, XILINX_DPDMA_GBL, reg);
904 }
905 
906 /**
907  * xilinx_dpdma_chan_ostand - Number of outstanding transactions
908  * @chan: DPDMA channel
909  *
910  * Read and return the number of outstanding transactions from register.
911  *
912  * Return: Number of outstanding transactions from the status register.
913  */
914 static u32 xilinx_dpdma_chan_ostand(struct xilinx_dpdma_chan *chan)
915 {
916 	return FIELD_GET(XILINX_DPDMA_CH_STATUS_OTRAN_CNT_MASK,
917 			 dpdma_read(chan->reg, XILINX_DPDMA_CH_STATUS));
918 }
919 
920 /**
921  * xilinx_dpdma_chan_notify_no_ostand - Notify no outstanding transaction event
922  * @chan: DPDMA channel
923  *
924  * Notify waiters for no outstanding event, so waiters can stop the channel
925  * safely. This function is supposed to be called when 'no outstanding'
926  * interrupt is generated. The 'no outstanding' interrupt is disabled and
927  * should be re-enabled when this event is handled. If the channel status
928  * register still shows some number of outstanding transactions, the interrupt
929  * remains enabled.
930  *
931  * Return: 0 on success. On failure, -EWOULDBLOCK if there's still outstanding
932  * transaction(s).
933  */
934 static int xilinx_dpdma_chan_notify_no_ostand(struct xilinx_dpdma_chan *chan)
935 {
936 	u32 cnt;
937 
938 	cnt = xilinx_dpdma_chan_ostand(chan);
939 	if (cnt) {
940 		dev_dbg(chan->xdev->dev,
941 			"chan%u: %d outstanding transactions\n",
942 			chan->id, cnt);
943 		return -EWOULDBLOCK;
944 	}
945 
946 	/* Disable 'no outstanding' interrupt */
947 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IDS,
948 		    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
949 	wake_up(&chan->wait_to_stop);
950 
951 	return 0;
952 }
953 
954 /**
955  * xilinx_dpdma_chan_wait_no_ostand - Wait for the no outstanding irq
956  * @chan: DPDMA channel
957  *
958  * Wait for the no outstanding transaction interrupt. This functions can sleep
959  * for 50ms.
960  *
961  * Return: 0 on success. On failure, -ETIMEOUT for time out, or the error code
962  * from wait_event_interruptible_timeout().
963  */
964 static int xilinx_dpdma_chan_wait_no_ostand(struct xilinx_dpdma_chan *chan)
965 {
966 	int ret;
967 
968 	/* Wait for a no outstanding transaction interrupt upto 50msec */
969 	ret = wait_event_interruptible_timeout(chan->wait_to_stop,
970 					       !xilinx_dpdma_chan_ostand(chan),
971 					       msecs_to_jiffies(50));
972 	if (ret > 0) {
973 		dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN,
974 			    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
975 		return 0;
976 	}
977 
978 	dev_err(chan->xdev->dev, "chan%u: not ready to stop: %d trans\n",
979 		chan->id, xilinx_dpdma_chan_ostand(chan));
980 
981 	if (ret == 0)
982 		return -ETIMEDOUT;
983 
984 	return ret;
985 }
986 
987 /**
988  * xilinx_dpdma_chan_poll_no_ostand - Poll the outstanding transaction status
989  * @chan: DPDMA channel
990  *
991  * Poll the outstanding transaction status, and return when there's no
992  * outstanding transaction. This functions can be used in the interrupt context
993  * or where the atomicity is required. Calling thread may wait more than 50ms.
994  *
995  * Return: 0 on success, or -ETIMEDOUT.
996  */
997 static int xilinx_dpdma_chan_poll_no_ostand(struct xilinx_dpdma_chan *chan)
998 {
999 	u32 cnt, loop = 50000;
1000 
1001 	/* Poll at least for 50ms (20 fps). */
1002 	do {
1003 		cnt = xilinx_dpdma_chan_ostand(chan);
1004 		udelay(1);
1005 	} while (loop-- > 0 && cnt);
1006 
1007 	if (loop) {
1008 		dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN,
1009 			    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
1010 		return 0;
1011 	}
1012 
1013 	dev_err(chan->xdev->dev, "chan%u: not ready to stop: %d trans\n",
1014 		chan->id, xilinx_dpdma_chan_ostand(chan));
1015 
1016 	return -ETIMEDOUT;
1017 }
1018 
1019 /**
1020  * xilinx_dpdma_chan_stop - Stop the channel
1021  * @chan: DPDMA channel
1022  *
1023  * Stop a previously paused channel by first waiting for completion of all
1024  * outstanding transaction and then disabling the channel.
1025  *
1026  * Return: 0 on success, or -ETIMEDOUT if the channel failed to stop.
1027  */
1028 static int xilinx_dpdma_chan_stop(struct xilinx_dpdma_chan *chan)
1029 {
1030 	unsigned long flags;
1031 	int ret;
1032 
1033 	ret = xilinx_dpdma_chan_wait_no_ostand(chan);
1034 	if (ret)
1035 		return ret;
1036 
1037 	spin_lock_irqsave(&chan->lock, flags);
1038 	xilinx_dpdma_chan_disable(chan);
1039 	chan->running = false;
1040 	spin_unlock_irqrestore(&chan->lock, flags);
1041 
1042 	return 0;
1043 }
1044 
1045 /**
1046  * xilinx_dpdma_chan_done_irq - Handle hardware descriptor completion
1047  * @chan: DPDMA channel
1048  *
1049  * Handle completion of the currently active descriptor (@chan->desc.active). As
1050  * we currently support cyclic transfers only, this just invokes the cyclic
1051  * callback. The descriptor will be completed at the VSYNC interrupt when a new
1052  * descriptor replaces it.
1053  */
1054 static void xilinx_dpdma_chan_done_irq(struct xilinx_dpdma_chan *chan)
1055 {
1056 	struct xilinx_dpdma_tx_desc *active;
1057 	unsigned long flags;
1058 
1059 	spin_lock_irqsave(&chan->lock, flags);
1060 
1061 	xilinx_dpdma_debugfs_desc_done_irq(chan);
1062 
1063 	active = chan->desc.active;
1064 	if (active)
1065 		vchan_cyclic_callback(&active->vdesc);
1066 	else
1067 		dev_warn(chan->xdev->dev,
1068 			 "chan%u: DONE IRQ with no active descriptor!\n",
1069 			 chan->id);
1070 
1071 	spin_unlock_irqrestore(&chan->lock, flags);
1072 }
1073 
1074 /**
1075  * xilinx_dpdma_chan_vsync_irq - Handle hardware descriptor scheduling
1076  * @chan: DPDMA channel
1077  *
1078  * At VSYNC the active descriptor may have been replaced by the pending
1079  * descriptor. Detect this through the DESC_ID and perform appropriate
1080  * bookkeeping.
1081  */
1082 static void xilinx_dpdma_chan_vsync_irq(struct  xilinx_dpdma_chan *chan)
1083 {
1084 	struct xilinx_dpdma_tx_desc *pending;
1085 	struct xilinx_dpdma_sw_desc *sw_desc;
1086 	unsigned long flags;
1087 	u32 desc_id;
1088 
1089 	spin_lock_irqsave(&chan->lock, flags);
1090 
1091 	pending = chan->desc.pending;
1092 	if (!chan->running || !pending)
1093 		goto out;
1094 
1095 	desc_id = dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_ID)
1096 		& XILINX_DPDMA_CH_DESC_ID_MASK;
1097 
1098 	/* If the retrigger raced with vsync, retry at the next frame. */
1099 	sw_desc = list_first_entry(&pending->descriptors,
1100 				   struct xilinx_dpdma_sw_desc, node);
1101 	if (sw_desc->hw.desc_id != desc_id) {
1102 		dev_dbg(chan->xdev->dev,
1103 			"chan%u: vsync race lost (%u != %u), retrying\n",
1104 			chan->id, sw_desc->hw.desc_id, desc_id);
1105 		goto out;
1106 	}
1107 
1108 	/*
1109 	 * Complete the active descriptor, if any, promote the pending
1110 	 * descriptor to active, and queue the next transfer, if any.
1111 	 */
1112 	if (chan->desc.active)
1113 		vchan_cookie_complete(&chan->desc.active->vdesc);
1114 	chan->desc.active = pending;
1115 	chan->desc.pending = NULL;
1116 
1117 	xilinx_dpdma_chan_queue_transfer(chan);
1118 
1119 out:
1120 	spin_unlock_irqrestore(&chan->lock, flags);
1121 }
1122 
1123 /**
1124  * xilinx_dpdma_chan_err - Detect any channel error
1125  * @chan: DPDMA channel
1126  * @isr: masked Interrupt Status Register
1127  * @eisr: Error Interrupt Status Register
1128  *
1129  * Return: true if any channel error occurs, or false otherwise.
1130  */
1131 static bool
1132 xilinx_dpdma_chan_err(struct xilinx_dpdma_chan *chan, u32 isr, u32 eisr)
1133 {
1134 	if (!chan)
1135 		return false;
1136 
1137 	if (chan->running &&
1138 	    ((isr & (XILINX_DPDMA_INTR_CHAN_ERR_MASK << chan->id)) ||
1139 	    (eisr & (XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id))))
1140 		return true;
1141 
1142 	return false;
1143 }
1144 
1145 /**
1146  * xilinx_dpdma_chan_handle_err - DPDMA channel error handling
1147  * @chan: DPDMA channel
1148  *
1149  * This function is called when any channel error or any global error occurs.
1150  * The function disables the paused channel by errors and determines
1151  * if the current active descriptor can be rescheduled depending on
1152  * the descriptor status.
1153  */
1154 static void xilinx_dpdma_chan_handle_err(struct xilinx_dpdma_chan *chan)
1155 {
1156 	struct xilinx_dpdma_device *xdev = chan->xdev;
1157 	struct xilinx_dpdma_tx_desc *active;
1158 	unsigned long flags;
1159 
1160 	spin_lock_irqsave(&chan->lock, flags);
1161 
1162 	dev_dbg(xdev->dev, "chan%u: cur desc addr = 0x%04x%08x\n",
1163 		chan->id,
1164 		dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDRE),
1165 		dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDR));
1166 	dev_dbg(xdev->dev, "chan%u: cur payload addr = 0x%04x%08x\n",
1167 		chan->id,
1168 		dpdma_read(chan->reg, XILINX_DPDMA_CH_PYLD_CUR_ADDRE),
1169 		dpdma_read(chan->reg, XILINX_DPDMA_CH_PYLD_CUR_ADDR));
1170 
1171 	xilinx_dpdma_chan_disable(chan);
1172 	chan->running = false;
1173 
1174 	if (!chan->desc.active)
1175 		goto out_unlock;
1176 
1177 	active = chan->desc.active;
1178 	chan->desc.active = NULL;
1179 
1180 	xilinx_dpdma_chan_dump_tx_desc(chan, active);
1181 
1182 	if (active->error)
1183 		dev_dbg(xdev->dev, "chan%u: repeated error on desc\n",
1184 			chan->id);
1185 
1186 	/* Reschedule if there's no new descriptor */
1187 	if (!chan->desc.pending &&
1188 	    list_empty(&chan->vchan.desc_issued)) {
1189 		active->error = true;
1190 		list_add_tail(&active->vdesc.node,
1191 			      &chan->vchan.desc_issued);
1192 	} else {
1193 		xilinx_dpdma_chan_free_tx_desc(&active->vdesc);
1194 	}
1195 
1196 out_unlock:
1197 	spin_unlock_irqrestore(&chan->lock, flags);
1198 }
1199 
1200 /* -----------------------------------------------------------------------------
1201  * DMA Engine Operations
1202  */
1203 
1204 static struct dma_async_tx_descriptor *
1205 xilinx_dpdma_prep_interleaved_dma(struct dma_chan *dchan,
1206 				  struct dma_interleaved_template *xt,
1207 				  unsigned long flags)
1208 {
1209 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1210 	struct xilinx_dpdma_tx_desc *desc;
1211 
1212 	if (xt->dir != DMA_MEM_TO_DEV)
1213 		return NULL;
1214 
1215 	if (!xt->numf || !xt->sgl[0].size)
1216 		return NULL;
1217 
1218 	if (!(flags & DMA_PREP_REPEAT) || !(flags & DMA_PREP_LOAD_EOT))
1219 		return NULL;
1220 
1221 	desc = xilinx_dpdma_chan_prep_interleaved_dma(chan, xt);
1222 	if (!desc)
1223 		return NULL;
1224 
1225 	vchan_tx_prep(&chan->vchan, &desc->vdesc, flags | DMA_CTRL_ACK);
1226 
1227 	return &desc->vdesc.tx;
1228 }
1229 
1230 /**
1231  * xilinx_dpdma_alloc_chan_resources - Allocate resources for the channel
1232  * @dchan: DMA channel
1233  *
1234  * Allocate a descriptor pool for the channel.
1235  *
1236  * Return: 0 on success, or -ENOMEM if failed to allocate a pool.
1237  */
1238 static int xilinx_dpdma_alloc_chan_resources(struct dma_chan *dchan)
1239 {
1240 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1241 	size_t align = __alignof__(struct xilinx_dpdma_sw_desc);
1242 
1243 	chan->desc_pool = dma_pool_create(dev_name(chan->xdev->dev),
1244 					  chan->xdev->dev,
1245 					  sizeof(struct xilinx_dpdma_sw_desc),
1246 					  align, 0);
1247 	if (!chan->desc_pool) {
1248 		dev_err(chan->xdev->dev,
1249 			"chan%u: failed to allocate a descriptor pool\n",
1250 			chan->id);
1251 		return -ENOMEM;
1252 	}
1253 
1254 	return 0;
1255 }
1256 
1257 /**
1258  * xilinx_dpdma_free_chan_resources - Free all resources for the channel
1259  * @dchan: DMA channel
1260  *
1261  * Free resources associated with the virtual DMA channel, and destroy the
1262  * descriptor pool.
1263  */
1264 static void xilinx_dpdma_free_chan_resources(struct dma_chan *dchan)
1265 {
1266 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1267 
1268 	vchan_free_chan_resources(&chan->vchan);
1269 
1270 	dma_pool_destroy(chan->desc_pool);
1271 	chan->desc_pool = NULL;
1272 }
1273 
1274 static void xilinx_dpdma_issue_pending(struct dma_chan *dchan)
1275 {
1276 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1277 	unsigned long flags;
1278 
1279 	spin_lock_irqsave(&chan->vchan.lock, flags);
1280 	if (vchan_issue_pending(&chan->vchan))
1281 		xilinx_dpdma_chan_queue_transfer(chan);
1282 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1283 }
1284 
1285 static int xilinx_dpdma_config(struct dma_chan *dchan,
1286 			       struct dma_slave_config *config)
1287 {
1288 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1289 	unsigned long flags;
1290 
1291 	/*
1292 	 * The destination address doesn't need to be specified as the DPDMA is
1293 	 * hardwired to the destination (the DP controller). The transfer
1294 	 * width, burst size and port window size are thus meaningless, they're
1295 	 * fixed both on the DPDMA side and on the DP controller side.
1296 	 */
1297 
1298 	spin_lock_irqsave(&chan->lock, flags);
1299 
1300 	/*
1301 	 * Abuse the slave_id to indicate that the channel is part of a video
1302 	 * group.
1303 	 */
1304 	if (chan->id <= ZYNQMP_DPDMA_VIDEO2)
1305 		chan->video_group = config->slave_id != 0;
1306 
1307 	spin_unlock_irqrestore(&chan->lock, flags);
1308 
1309 	return 0;
1310 }
1311 
1312 static int xilinx_dpdma_pause(struct dma_chan *dchan)
1313 {
1314 	xilinx_dpdma_chan_pause(to_xilinx_chan(dchan));
1315 
1316 	return 0;
1317 }
1318 
1319 static int xilinx_dpdma_resume(struct dma_chan *dchan)
1320 {
1321 	xilinx_dpdma_chan_unpause(to_xilinx_chan(dchan));
1322 
1323 	return 0;
1324 }
1325 
1326 /**
1327  * xilinx_dpdma_terminate_all - Terminate the channel and descriptors
1328  * @dchan: DMA channel
1329  *
1330  * Pause the channel without waiting for ongoing transfers to complete. Waiting
1331  * for completion is performed by xilinx_dpdma_synchronize() that will disable
1332  * the channel to complete the stop.
1333  *
1334  * All the descriptors associated with the channel that are guaranteed not to
1335  * be touched by the hardware. The pending and active descriptor are not
1336  * touched, and will be freed either upon completion, or by
1337  * xilinx_dpdma_synchronize().
1338  *
1339  * Return: 0 on success, or -ETIMEDOUT if the channel failed to stop.
1340  */
1341 static int xilinx_dpdma_terminate_all(struct dma_chan *dchan)
1342 {
1343 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1344 	struct xilinx_dpdma_device *xdev = chan->xdev;
1345 	LIST_HEAD(descriptors);
1346 	unsigned long flags;
1347 	unsigned int i;
1348 
1349 	/* Pause the channel (including the whole video group if applicable). */
1350 	if (chan->video_group) {
1351 		for (i = ZYNQMP_DPDMA_VIDEO0; i <= ZYNQMP_DPDMA_VIDEO2; i++) {
1352 			if (xdev->chan[i]->video_group &&
1353 			    xdev->chan[i]->running) {
1354 				xilinx_dpdma_chan_pause(xdev->chan[i]);
1355 				xdev->chan[i]->video_group = false;
1356 			}
1357 		}
1358 	} else {
1359 		xilinx_dpdma_chan_pause(chan);
1360 	}
1361 
1362 	/* Gather all the descriptors we can free and free them. */
1363 	spin_lock_irqsave(&chan->vchan.lock, flags);
1364 	vchan_get_all_descriptors(&chan->vchan, &descriptors);
1365 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1366 
1367 	vchan_dma_desc_free_list(&chan->vchan, &descriptors);
1368 
1369 	return 0;
1370 }
1371 
1372 /**
1373  * xilinx_dpdma_synchronize - Synchronize callback execution
1374  * @dchan: DMA channel
1375  *
1376  * Synchronizing callback execution ensures that all previously issued
1377  * transfers have completed and all associated callbacks have been called and
1378  * have returned.
1379  *
1380  * This function waits for the DMA channel to stop. It assumes it has been
1381  * paused by a previous call to dmaengine_terminate_async(), and that no new
1382  * pending descriptors have been issued with dma_async_issue_pending(). The
1383  * behaviour is undefined otherwise.
1384  */
1385 static void xilinx_dpdma_synchronize(struct dma_chan *dchan)
1386 {
1387 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1388 	unsigned long flags;
1389 
1390 	xilinx_dpdma_chan_stop(chan);
1391 
1392 	spin_lock_irqsave(&chan->vchan.lock, flags);
1393 	if (chan->desc.pending) {
1394 		vchan_terminate_vdesc(&chan->desc.pending->vdesc);
1395 		chan->desc.pending = NULL;
1396 	}
1397 	if (chan->desc.active) {
1398 		vchan_terminate_vdesc(&chan->desc.active->vdesc);
1399 		chan->desc.active = NULL;
1400 	}
1401 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1402 
1403 	vchan_synchronize(&chan->vchan);
1404 }
1405 
1406 /* -----------------------------------------------------------------------------
1407  * Interrupt and Tasklet Handling
1408  */
1409 
1410 /**
1411  * xilinx_dpdma_err - Detect any global error
1412  * @isr: Interrupt Status Register
1413  * @eisr: Error Interrupt Status Register
1414  *
1415  * Return: True if any global error occurs, or false otherwise.
1416  */
1417 static bool xilinx_dpdma_err(u32 isr, u32 eisr)
1418 {
1419 	if (isr & XILINX_DPDMA_INTR_GLOBAL_ERR ||
1420 	    eisr & XILINX_DPDMA_EINTR_GLOBAL_ERR)
1421 		return true;
1422 
1423 	return false;
1424 }
1425 
1426 /**
1427  * xilinx_dpdma_handle_err_irq - Handle DPDMA error interrupt
1428  * @xdev: DPDMA device
1429  * @isr: masked Interrupt Status Register
1430  * @eisr: Error Interrupt Status Register
1431  *
1432  * Handle if any error occurs based on @isr and @eisr. This function disables
1433  * corresponding error interrupts, and those should be re-enabled once handling
1434  * is done.
1435  */
1436 static void xilinx_dpdma_handle_err_irq(struct xilinx_dpdma_device *xdev,
1437 					u32 isr, u32 eisr)
1438 {
1439 	bool err = xilinx_dpdma_err(isr, eisr);
1440 	unsigned int i;
1441 
1442 	dev_dbg_ratelimited(xdev->dev,
1443 			    "error irq: isr = 0x%08x, eisr = 0x%08x\n",
1444 			    isr, eisr);
1445 
1446 	/* Disable channel error interrupts until errors are handled. */
1447 	dpdma_write(xdev->reg, XILINX_DPDMA_IDS,
1448 		    isr & ~XILINX_DPDMA_INTR_GLOBAL_ERR);
1449 	dpdma_write(xdev->reg, XILINX_DPDMA_EIDS,
1450 		    eisr & ~XILINX_DPDMA_EINTR_GLOBAL_ERR);
1451 
1452 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1453 		if (err || xilinx_dpdma_chan_err(xdev->chan[i], isr, eisr))
1454 			tasklet_schedule(&xdev->chan[i]->err_task);
1455 }
1456 
1457 /**
1458  * xilinx_dpdma_enable_irq - Enable interrupts
1459  * @xdev: DPDMA device
1460  *
1461  * Enable interrupts.
1462  */
1463 static void xilinx_dpdma_enable_irq(struct xilinx_dpdma_device *xdev)
1464 {
1465 	dpdma_write(xdev->reg, XILINX_DPDMA_IEN, XILINX_DPDMA_INTR_ALL);
1466 	dpdma_write(xdev->reg, XILINX_DPDMA_EIEN, XILINX_DPDMA_EINTR_ALL);
1467 }
1468 
1469 /**
1470  * xilinx_dpdma_disable_irq - Disable interrupts
1471  * @xdev: DPDMA device
1472  *
1473  * Disable interrupts.
1474  */
1475 static void xilinx_dpdma_disable_irq(struct xilinx_dpdma_device *xdev)
1476 {
1477 	dpdma_write(xdev->reg, XILINX_DPDMA_IDS, XILINX_DPDMA_INTR_ALL);
1478 	dpdma_write(xdev->reg, XILINX_DPDMA_EIDS, XILINX_DPDMA_EINTR_ALL);
1479 }
1480 
1481 /**
1482  * xilinx_dpdma_chan_err_task - Per channel tasklet for error handling
1483  * @t: pointer to the tasklet associated with this handler
1484  *
1485  * Per channel error handling tasklet. This function waits for the outstanding
1486  * transaction to complete and triggers error handling. After error handling,
1487  * re-enable channel error interrupts, and restart the channel if needed.
1488  */
1489 static void xilinx_dpdma_chan_err_task(struct tasklet_struct *t)
1490 {
1491 	struct xilinx_dpdma_chan *chan = from_tasklet(chan, t, err_task);
1492 	struct xilinx_dpdma_device *xdev = chan->xdev;
1493 	unsigned long flags;
1494 
1495 	/* Proceed error handling even when polling fails. */
1496 	xilinx_dpdma_chan_poll_no_ostand(chan);
1497 
1498 	xilinx_dpdma_chan_handle_err(chan);
1499 
1500 	dpdma_write(xdev->reg, XILINX_DPDMA_IEN,
1501 		    XILINX_DPDMA_INTR_CHAN_ERR_MASK << chan->id);
1502 	dpdma_write(xdev->reg, XILINX_DPDMA_EIEN,
1503 		    XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id);
1504 
1505 	spin_lock_irqsave(&chan->lock, flags);
1506 	xilinx_dpdma_chan_queue_transfer(chan);
1507 	spin_unlock_irqrestore(&chan->lock, flags);
1508 }
1509 
1510 static irqreturn_t xilinx_dpdma_irq_handler(int irq, void *data)
1511 {
1512 	struct xilinx_dpdma_device *xdev = data;
1513 	unsigned long mask;
1514 	unsigned int i;
1515 	u32 status;
1516 	u32 error;
1517 
1518 	status = dpdma_read(xdev->reg, XILINX_DPDMA_ISR);
1519 	error = dpdma_read(xdev->reg, XILINX_DPDMA_EISR);
1520 	if (!status && !error)
1521 		return IRQ_NONE;
1522 
1523 	dpdma_write(xdev->reg, XILINX_DPDMA_ISR, status);
1524 	dpdma_write(xdev->reg, XILINX_DPDMA_EISR, error);
1525 
1526 	if (status & XILINX_DPDMA_INTR_VSYNC) {
1527 		/*
1528 		 * There's a single VSYNC interrupt that needs to be processed
1529 		 * by each running channel to update the active descriptor.
1530 		 */
1531 		for (i = 0; i < ARRAY_SIZE(xdev->chan); i++) {
1532 			struct xilinx_dpdma_chan *chan = xdev->chan[i];
1533 
1534 			if (chan)
1535 				xilinx_dpdma_chan_vsync_irq(chan);
1536 		}
1537 	}
1538 
1539 	mask = FIELD_GET(XILINX_DPDMA_INTR_DESC_DONE_MASK, status);
1540 	if (mask) {
1541 		for_each_set_bit(i, &mask, ARRAY_SIZE(xdev->chan))
1542 			xilinx_dpdma_chan_done_irq(xdev->chan[i]);
1543 	}
1544 
1545 	mask = FIELD_GET(XILINX_DPDMA_INTR_NO_OSTAND_MASK, status);
1546 	if (mask) {
1547 		for_each_set_bit(i, &mask, ARRAY_SIZE(xdev->chan))
1548 			xilinx_dpdma_chan_notify_no_ostand(xdev->chan[i]);
1549 	}
1550 
1551 	mask = status & XILINX_DPDMA_INTR_ERR_ALL;
1552 	if (mask || error)
1553 		xilinx_dpdma_handle_err_irq(xdev, mask, error);
1554 
1555 	return IRQ_HANDLED;
1556 }
1557 
1558 /* -----------------------------------------------------------------------------
1559  * Initialization & Cleanup
1560  */
1561 
1562 static int xilinx_dpdma_chan_init(struct xilinx_dpdma_device *xdev,
1563 				  unsigned int chan_id)
1564 {
1565 	struct xilinx_dpdma_chan *chan;
1566 
1567 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
1568 	if (!chan)
1569 		return -ENOMEM;
1570 
1571 	chan->id = chan_id;
1572 	chan->reg = xdev->reg + XILINX_DPDMA_CH_BASE
1573 		  + XILINX_DPDMA_CH_OFFSET * chan->id;
1574 	chan->running = false;
1575 	chan->xdev = xdev;
1576 
1577 	spin_lock_init(&chan->lock);
1578 	init_waitqueue_head(&chan->wait_to_stop);
1579 
1580 	tasklet_setup(&chan->err_task, xilinx_dpdma_chan_err_task);
1581 
1582 	chan->vchan.desc_free = xilinx_dpdma_chan_free_tx_desc;
1583 	vchan_init(&chan->vchan, &xdev->common);
1584 
1585 	xdev->chan[chan->id] = chan;
1586 
1587 	return 0;
1588 }
1589 
1590 static void xilinx_dpdma_chan_remove(struct xilinx_dpdma_chan *chan)
1591 {
1592 	if (!chan)
1593 		return;
1594 
1595 	tasklet_kill(&chan->err_task);
1596 	list_del(&chan->vchan.chan.device_node);
1597 }
1598 
1599 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
1600 					    struct of_dma *ofdma)
1601 {
1602 	struct xilinx_dpdma_device *xdev = ofdma->of_dma_data;
1603 	u32 chan_id = dma_spec->args[0];
1604 
1605 	if (chan_id >= ARRAY_SIZE(xdev->chan))
1606 		return NULL;
1607 
1608 	if (!xdev->chan[chan_id])
1609 		return NULL;
1610 
1611 	return dma_get_slave_channel(&xdev->chan[chan_id]->vchan.chan);
1612 }
1613 
1614 static void dpdma_hw_init(struct xilinx_dpdma_device *xdev)
1615 {
1616 	unsigned int i;
1617 	void __iomem *reg;
1618 
1619 	/* Disable all interrupts */
1620 	xilinx_dpdma_disable_irq(xdev);
1621 
1622 	/* Stop all channels */
1623 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++) {
1624 		reg = xdev->reg + XILINX_DPDMA_CH_BASE
1625 				+ XILINX_DPDMA_CH_OFFSET * i;
1626 		dpdma_clr(reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_ENABLE);
1627 	}
1628 
1629 	/* Clear the interrupt status registers */
1630 	dpdma_write(xdev->reg, XILINX_DPDMA_ISR, XILINX_DPDMA_INTR_ALL);
1631 	dpdma_write(xdev->reg, XILINX_DPDMA_EISR, XILINX_DPDMA_EINTR_ALL);
1632 }
1633 
1634 static int xilinx_dpdma_probe(struct platform_device *pdev)
1635 {
1636 	struct xilinx_dpdma_device *xdev;
1637 	struct dma_device *ddev;
1638 	unsigned int i;
1639 	int ret;
1640 
1641 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
1642 	if (!xdev)
1643 		return -ENOMEM;
1644 
1645 	xdev->dev = &pdev->dev;
1646 	xdev->ext_addr = sizeof(dma_addr_t) > 4;
1647 
1648 	INIT_LIST_HEAD(&xdev->common.channels);
1649 
1650 	platform_set_drvdata(pdev, xdev);
1651 
1652 	xdev->axi_clk = devm_clk_get(xdev->dev, "axi_clk");
1653 	if (IS_ERR(xdev->axi_clk))
1654 		return PTR_ERR(xdev->axi_clk);
1655 
1656 	xdev->reg = devm_platform_ioremap_resource(pdev, 0);
1657 	if (IS_ERR(xdev->reg))
1658 		return PTR_ERR(xdev->reg);
1659 
1660 	dpdma_hw_init(xdev);
1661 
1662 	xdev->irq = platform_get_irq(pdev, 0);
1663 	if (xdev->irq < 0) {
1664 		dev_err(xdev->dev, "failed to get platform irq\n");
1665 		return xdev->irq;
1666 	}
1667 
1668 	ret = request_irq(xdev->irq, xilinx_dpdma_irq_handler, IRQF_SHARED,
1669 			  dev_name(xdev->dev), xdev);
1670 	if (ret) {
1671 		dev_err(xdev->dev, "failed to request IRQ\n");
1672 		return ret;
1673 	}
1674 
1675 	ddev = &xdev->common;
1676 	ddev->dev = &pdev->dev;
1677 
1678 	dma_cap_set(DMA_SLAVE, ddev->cap_mask);
1679 	dma_cap_set(DMA_PRIVATE, ddev->cap_mask);
1680 	dma_cap_set(DMA_INTERLEAVE, ddev->cap_mask);
1681 	dma_cap_set(DMA_REPEAT, ddev->cap_mask);
1682 	dma_cap_set(DMA_LOAD_EOT, ddev->cap_mask);
1683 	ddev->copy_align = fls(XILINX_DPDMA_ALIGN_BYTES - 1);
1684 
1685 	ddev->device_alloc_chan_resources = xilinx_dpdma_alloc_chan_resources;
1686 	ddev->device_free_chan_resources = xilinx_dpdma_free_chan_resources;
1687 	ddev->device_prep_interleaved_dma = xilinx_dpdma_prep_interleaved_dma;
1688 	/* TODO: Can we achieve better granularity ? */
1689 	ddev->device_tx_status = dma_cookie_status;
1690 	ddev->device_issue_pending = xilinx_dpdma_issue_pending;
1691 	ddev->device_config = xilinx_dpdma_config;
1692 	ddev->device_pause = xilinx_dpdma_pause;
1693 	ddev->device_resume = xilinx_dpdma_resume;
1694 	ddev->device_terminate_all = xilinx_dpdma_terminate_all;
1695 	ddev->device_synchronize = xilinx_dpdma_synchronize;
1696 	ddev->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED);
1697 	ddev->directions = BIT(DMA_MEM_TO_DEV);
1698 	ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1699 
1700 	for (i = 0; i < ARRAY_SIZE(xdev->chan); ++i) {
1701 		ret = xilinx_dpdma_chan_init(xdev, i);
1702 		if (ret < 0) {
1703 			dev_err(xdev->dev, "failed to initialize channel %u\n",
1704 				i);
1705 			goto error;
1706 		}
1707 	}
1708 
1709 	ret = clk_prepare_enable(xdev->axi_clk);
1710 	if (ret) {
1711 		dev_err(xdev->dev, "failed to enable the axi clock\n");
1712 		goto error;
1713 	}
1714 
1715 	ret = dma_async_device_register(ddev);
1716 	if (ret) {
1717 		dev_err(xdev->dev, "failed to register the dma device\n");
1718 		goto error_dma_async;
1719 	}
1720 
1721 	ret = of_dma_controller_register(xdev->dev->of_node,
1722 					 of_dma_xilinx_xlate, ddev);
1723 	if (ret) {
1724 		dev_err(xdev->dev, "failed to register DMA to DT DMA helper\n");
1725 		goto error_of_dma;
1726 	}
1727 
1728 	xilinx_dpdma_enable_irq(xdev);
1729 
1730 	xilinx_dpdma_debugfs_init(xdev);
1731 
1732 	dev_info(&pdev->dev, "Xilinx DPDMA engine is probed\n");
1733 
1734 	return 0;
1735 
1736 error_of_dma:
1737 	dma_async_device_unregister(ddev);
1738 error_dma_async:
1739 	clk_disable_unprepare(xdev->axi_clk);
1740 error:
1741 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1742 		xilinx_dpdma_chan_remove(xdev->chan[i]);
1743 
1744 	free_irq(xdev->irq, xdev);
1745 
1746 	return ret;
1747 }
1748 
1749 static int xilinx_dpdma_remove(struct platform_device *pdev)
1750 {
1751 	struct xilinx_dpdma_device *xdev = platform_get_drvdata(pdev);
1752 	unsigned int i;
1753 
1754 	/* Start by disabling the IRQ to avoid races during cleanup. */
1755 	free_irq(xdev->irq, xdev);
1756 
1757 	xilinx_dpdma_disable_irq(xdev);
1758 	of_dma_controller_free(pdev->dev.of_node);
1759 	dma_async_device_unregister(&xdev->common);
1760 	clk_disable_unprepare(xdev->axi_clk);
1761 
1762 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1763 		xilinx_dpdma_chan_remove(xdev->chan[i]);
1764 
1765 	return 0;
1766 }
1767 
1768 static const struct of_device_id xilinx_dpdma_of_match[] = {
1769 	{ .compatible = "xlnx,zynqmp-dpdma",},
1770 	{ /* end of table */ },
1771 };
1772 MODULE_DEVICE_TABLE(of, xilinx_dpdma_of_match);
1773 
1774 static struct platform_driver xilinx_dpdma_driver = {
1775 	.probe			= xilinx_dpdma_probe,
1776 	.remove			= xilinx_dpdma_remove,
1777 	.driver			= {
1778 		.name		= "xilinx-zynqmp-dpdma",
1779 		.of_match_table	= xilinx_dpdma_of_match,
1780 	},
1781 };
1782 
1783 module_platform_driver(xilinx_dpdma_driver);
1784 
1785 MODULE_AUTHOR("Xilinx, Inc.");
1786 MODULE_DESCRIPTION("Xilinx ZynqMP DPDMA driver");
1787 MODULE_LICENSE("GPL v2");
1788