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/dma/xilinx_dpdma.h>
16 #include <linux/dmaengine.h>
17 #include <linux/dmapool.h>
18 #include <linux/interrupt.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/of_dma.h>
22 #include <linux/platform_device.h>
23 #include <linux/sched.h>
24 #include <linux/slab.h>
25 #include <linux/spinlock.h>
26 #include <linux/wait.h>
27 
28 #include <dt-bindings/dma/xlnx-zynqmp-dpdma.h>
29 
30 #include "../dmaengine.h"
31 #include "../virt-dma.h"
32 
33 /* DPDMA registers */
34 #define XILINX_DPDMA_ERR_CTRL				0x000
35 #define XILINX_DPDMA_ISR				0x004
36 #define XILINX_DPDMA_IMR				0x008
37 #define XILINX_DPDMA_IEN				0x00c
38 #define XILINX_DPDMA_IDS				0x010
39 #define XILINX_DPDMA_INTR_DESC_DONE(n)			BIT((n) + 0)
40 #define XILINX_DPDMA_INTR_DESC_DONE_MASK		GENMASK(5, 0)
41 #define XILINX_DPDMA_INTR_NO_OSTAND(n)			BIT((n) + 6)
42 #define XILINX_DPDMA_INTR_NO_OSTAND_MASK		GENMASK(11, 6)
43 #define XILINX_DPDMA_INTR_AXI_ERR(n)			BIT((n) + 12)
44 #define XILINX_DPDMA_INTR_AXI_ERR_MASK			GENMASK(17, 12)
45 #define XILINX_DPDMA_INTR_DESC_ERR(n)			BIT((n) + 16)
46 #define XILINX_DPDMA_INTR_DESC_ERR_MASK			GENMASK(23, 18)
47 #define XILINX_DPDMA_INTR_WR_CMD_FIFO_FULL		BIT(24)
48 #define XILINX_DPDMA_INTR_WR_DATA_FIFO_FULL		BIT(25)
49 #define XILINX_DPDMA_INTR_AXI_4K_CROSS			BIT(26)
50 #define XILINX_DPDMA_INTR_VSYNC				BIT(27)
51 #define XILINX_DPDMA_INTR_CHAN_ERR_MASK			0x00041000
52 #define XILINX_DPDMA_INTR_CHAN_ERR			0x00fff000
53 #define XILINX_DPDMA_INTR_GLOBAL_ERR			0x07000000
54 #define XILINX_DPDMA_INTR_ERR_ALL			0x07fff000
55 #define XILINX_DPDMA_INTR_CHAN_MASK			0x00041041
56 #define XILINX_DPDMA_INTR_GLOBAL_MASK			0x0f000000
57 #define XILINX_DPDMA_INTR_ALL				0x0fffffff
58 #define XILINX_DPDMA_EISR				0x014
59 #define XILINX_DPDMA_EIMR				0x018
60 #define XILINX_DPDMA_EIEN				0x01c
61 #define XILINX_DPDMA_EIDS				0x020
62 #define XILINX_DPDMA_EINTR_INV_APB			BIT(0)
63 #define XILINX_DPDMA_EINTR_RD_AXI_ERR(n)		BIT((n) + 1)
64 #define XILINX_DPDMA_EINTR_RD_AXI_ERR_MASK		GENMASK(6, 1)
65 #define XILINX_DPDMA_EINTR_PRE_ERR(n)			BIT((n) + 7)
66 #define XILINX_DPDMA_EINTR_PRE_ERR_MASK			GENMASK(12, 7)
67 #define XILINX_DPDMA_EINTR_CRC_ERR(n)			BIT((n) + 13)
68 #define XILINX_DPDMA_EINTR_CRC_ERR_MASK			GENMASK(18, 13)
69 #define XILINX_DPDMA_EINTR_WR_AXI_ERR(n)		BIT((n) + 19)
70 #define XILINX_DPDMA_EINTR_WR_AXI_ERR_MASK		GENMASK(24, 19)
71 #define XILINX_DPDMA_EINTR_DESC_DONE_ERR(n)		BIT((n) + 25)
72 #define XILINX_DPDMA_EINTR_DESC_DONE_ERR_MASK		GENMASK(30, 25)
73 #define XILINX_DPDMA_EINTR_RD_CMD_FIFO_FULL		BIT(32)
74 #define XILINX_DPDMA_EINTR_CHAN_ERR_MASK		0x02082082
75 #define XILINX_DPDMA_EINTR_CHAN_ERR			0x7ffffffe
76 #define XILINX_DPDMA_EINTR_GLOBAL_ERR			0x80000001
77 #define XILINX_DPDMA_EINTR_ALL				0xffffffff
78 #define XILINX_DPDMA_CNTL				0x100
79 #define XILINX_DPDMA_GBL				0x104
80 #define XILINX_DPDMA_GBL_TRIG_MASK(n)			((n) << 0)
81 #define XILINX_DPDMA_GBL_RETRIG_MASK(n)			((n) << 6)
82 #define XILINX_DPDMA_ALC0_CNTL				0x108
83 #define XILINX_DPDMA_ALC0_STATUS			0x10c
84 #define XILINX_DPDMA_ALC0_MAX				0x110
85 #define XILINX_DPDMA_ALC0_MIN				0x114
86 #define XILINX_DPDMA_ALC0_ACC				0x118
87 #define XILINX_DPDMA_ALC0_ACC_TRAN			0x11c
88 #define XILINX_DPDMA_ALC1_CNTL				0x120
89 #define XILINX_DPDMA_ALC1_STATUS			0x124
90 #define XILINX_DPDMA_ALC1_MAX				0x128
91 #define XILINX_DPDMA_ALC1_MIN				0x12c
92 #define XILINX_DPDMA_ALC1_ACC				0x130
93 #define XILINX_DPDMA_ALC1_ACC_TRAN			0x134
94 
95 /* Channel register */
96 #define XILINX_DPDMA_CH_BASE				0x200
97 #define XILINX_DPDMA_CH_OFFSET				0x100
98 #define XILINX_DPDMA_CH_DESC_START_ADDRE		0x000
99 #define XILINX_DPDMA_CH_DESC_START_ADDRE_MASK		GENMASK(15, 0)
100 #define XILINX_DPDMA_CH_DESC_START_ADDR			0x004
101 #define XILINX_DPDMA_CH_DESC_NEXT_ADDRE			0x008
102 #define XILINX_DPDMA_CH_DESC_NEXT_ADDR			0x00c
103 #define XILINX_DPDMA_CH_PYLD_CUR_ADDRE			0x010
104 #define XILINX_DPDMA_CH_PYLD_CUR_ADDR			0x014
105 #define XILINX_DPDMA_CH_CNTL				0x018
106 #define XILINX_DPDMA_CH_CNTL_ENABLE			BIT(0)
107 #define XILINX_DPDMA_CH_CNTL_PAUSE			BIT(1)
108 #define XILINX_DPDMA_CH_CNTL_QOS_DSCR_WR_MASK		GENMASK(5, 2)
109 #define XILINX_DPDMA_CH_CNTL_QOS_DSCR_RD_MASK		GENMASK(9, 6)
110 #define XILINX_DPDMA_CH_CNTL_QOS_DATA_RD_MASK		GENMASK(13, 10)
111 #define XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS		11
112 #define XILINX_DPDMA_CH_STATUS				0x01c
113 #define XILINX_DPDMA_CH_STATUS_OTRAN_CNT_MASK		GENMASK(24, 21)
114 #define XILINX_DPDMA_CH_VDO				0x020
115 #define XILINX_DPDMA_CH_PYLD_SZ				0x024
116 #define XILINX_DPDMA_CH_DESC_ID				0x028
117 #define XILINX_DPDMA_CH_DESC_ID_MASK			GENMASK(15, 0)
118 
119 /* DPDMA descriptor fields */
120 #define XILINX_DPDMA_DESC_CONTROL_PREEMBLE		0xa5
121 #define XILINX_DPDMA_DESC_CONTROL_COMPLETE_INTR		BIT(8)
122 #define XILINX_DPDMA_DESC_CONTROL_DESC_UPDATE		BIT(9)
123 #define XILINX_DPDMA_DESC_CONTROL_IGNORE_DONE		BIT(10)
124 #define XILINX_DPDMA_DESC_CONTROL_FRAG_MODE		BIT(18)
125 #define XILINX_DPDMA_DESC_CONTROL_LAST			BIT(19)
126 #define XILINX_DPDMA_DESC_CONTROL_ENABLE_CRC		BIT(20)
127 #define XILINX_DPDMA_DESC_CONTROL_LAST_OF_FRAME		BIT(21)
128 #define XILINX_DPDMA_DESC_ID_MASK			GENMASK(15, 0)
129 #define XILINX_DPDMA_DESC_HSIZE_STRIDE_HSIZE_MASK	GENMASK(17, 0)
130 #define XILINX_DPDMA_DESC_HSIZE_STRIDE_STRIDE_MASK	GENMASK(31, 18)
131 #define XILINX_DPDMA_DESC_ADDR_EXT_NEXT_ADDR_MASK	GENMASK(15, 0)
132 #define XILINX_DPDMA_DESC_ADDR_EXT_SRC_ADDR_MASK	GENMASK(31, 16)
133 
134 #define XILINX_DPDMA_ALIGN_BYTES			256
135 #define XILINX_DPDMA_LINESIZE_ALIGN_BITS		128
136 
137 #define XILINX_DPDMA_NUM_CHAN				6
138 
139 struct xilinx_dpdma_chan;
140 
141 /**
142  * struct xilinx_dpdma_hw_desc - DPDMA hardware descriptor
143  * @control: control configuration field
144  * @desc_id: descriptor ID
145  * @xfer_size: transfer size
146  * @hsize_stride: horizontal size and stride
147  * @timestamp_lsb: LSB of time stamp
148  * @timestamp_msb: MSB of time stamp
149  * @addr_ext: upper 16 bit of 48 bit address (next_desc and src_addr)
150  * @next_desc: next descriptor 32 bit address
151  * @src_addr: payload source address (1st page, 32 LSB)
152  * @addr_ext_23: payload source address (3nd and 3rd pages, 16 LSBs)
153  * @addr_ext_45: payload source address (4th and 5th pages, 16 LSBs)
154  * @src_addr2: payload source address (2nd page, 32 LSB)
155  * @src_addr3: payload source address (3rd page, 32 LSB)
156  * @src_addr4: payload source address (4th page, 32 LSB)
157  * @src_addr5: payload source address (5th page, 32 LSB)
158  * @crc: descriptor CRC
159  */
160 struct xilinx_dpdma_hw_desc {
161 	u32 control;
162 	u32 desc_id;
163 	u32 xfer_size;
164 	u32 hsize_stride;
165 	u32 timestamp_lsb;
166 	u32 timestamp_msb;
167 	u32 addr_ext;
168 	u32 next_desc;
169 	u32 src_addr;
170 	u32 addr_ext_23;
171 	u32 addr_ext_45;
172 	u32 src_addr2;
173 	u32 src_addr3;
174 	u32 src_addr4;
175 	u32 src_addr5;
176 	u32 crc;
177 } __aligned(XILINX_DPDMA_ALIGN_BYTES);
178 
179 /**
180  * struct xilinx_dpdma_sw_desc - DPDMA software descriptor
181  * @hw: DPDMA hardware descriptor
182  * @node: list node for software descriptors
183  * @dma_addr: DMA address of the software descriptor
184  */
185 struct xilinx_dpdma_sw_desc {
186 	struct xilinx_dpdma_hw_desc hw;
187 	struct list_head node;
188 	dma_addr_t dma_addr;
189 };
190 
191 /**
192  * struct xilinx_dpdma_tx_desc - DPDMA transaction descriptor
193  * @vdesc: virtual DMA descriptor
194  * @chan: DMA channel
195  * @descriptors: list of software descriptors
196  * @error: an error has been detected with this descriptor
197  */
198 struct xilinx_dpdma_tx_desc {
199 	struct virt_dma_desc vdesc;
200 	struct xilinx_dpdma_chan *chan;
201 	struct list_head descriptors;
202 	bool error;
203 };
204 
205 #define to_dpdma_tx_desc(_desc) \
206 	container_of(_desc, struct xilinx_dpdma_tx_desc, vdesc)
207 
208 /**
209  * struct xilinx_dpdma_chan - DPDMA channel
210  * @vchan: virtual DMA channel
211  * @reg: register base address
212  * @id: channel ID
213  * @wait_to_stop: queue to wait for outstanding transacitons before stopping
214  * @running: true if the channel is running
215  * @first_frame: flag for the first frame of stream
216  * @video_group: flag if multi-channel operation is needed for video channels
217  * @lock: lock to access struct xilinx_dpdma_chan
218  * @desc_pool: descriptor allocation pool
219  * @err_task: error IRQ bottom half handler
220  * @desc: References to descriptors being processed
221  * @desc.pending: Descriptor schedule to the hardware, pending execution
222  * @desc.active: Descriptor being executed by the hardware
223  * @xdev: DPDMA device
224  */
225 struct xilinx_dpdma_chan {
226 	struct virt_dma_chan vchan;
227 	void __iomem *reg;
228 	unsigned int id;
229 
230 	wait_queue_head_t wait_to_stop;
231 	bool running;
232 	bool first_frame;
233 	bool video_group;
234 
235 	spinlock_t lock; /* lock to access struct xilinx_dpdma_chan */
236 	struct dma_pool *desc_pool;
237 	struct tasklet_struct err_task;
238 
239 	struct {
240 		struct xilinx_dpdma_tx_desc *pending;
241 		struct xilinx_dpdma_tx_desc *active;
242 	} desc;
243 
244 	struct xilinx_dpdma_device *xdev;
245 };
246 
247 #define to_xilinx_chan(_chan) \
248 	container_of(_chan, struct xilinx_dpdma_chan, vchan.chan)
249 
250 /**
251  * struct xilinx_dpdma_device - DPDMA device
252  * @common: generic dma device structure
253  * @reg: register base address
254  * @dev: generic device structure
255  * @irq: the interrupt number
256  * @axi_clk: axi clock
257  * @chan: DPDMA channels
258  * @ext_addr: flag for 64 bit system (48 bit addressing)
259  */
260 struct xilinx_dpdma_device {
261 	struct dma_device common;
262 	void __iomem *reg;
263 	struct device *dev;
264 	int irq;
265 
266 	struct clk *axi_clk;
267 	struct xilinx_dpdma_chan *chan[XILINX_DPDMA_NUM_CHAN];
268 
269 	bool ext_addr;
270 };
271 
272 /* -----------------------------------------------------------------------------
273  * DebugFS
274  */
275 #define XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE	32
276 #define XILINX_DPDMA_DEBUGFS_UINT16_MAX_STR	"65535"
277 
278 /* Match xilinx_dpdma_testcases vs dpdma_debugfs_reqs[] entry */
279 enum xilinx_dpdma_testcases {
280 	DPDMA_TC_INTR_DONE,
281 	DPDMA_TC_NONE
282 };
283 
284 struct xilinx_dpdma_debugfs {
285 	enum xilinx_dpdma_testcases testcase;
286 	u16 xilinx_dpdma_irq_done_count;
287 	unsigned int chan_id;
288 };
289 
290 static struct xilinx_dpdma_debugfs dpdma_debugfs;
291 struct xilinx_dpdma_debugfs_request {
292 	const char *name;
293 	enum xilinx_dpdma_testcases tc;
294 	ssize_t (*read)(char *buf);
295 	int (*write)(char *args);
296 };
297 
xilinx_dpdma_debugfs_desc_done_irq(struct xilinx_dpdma_chan * chan)298 static void xilinx_dpdma_debugfs_desc_done_irq(struct xilinx_dpdma_chan *chan)
299 {
300 	if (IS_ENABLED(CONFIG_DEBUG_FS) && chan->id == dpdma_debugfs.chan_id)
301 		dpdma_debugfs.xilinx_dpdma_irq_done_count++;
302 }
303 
xilinx_dpdma_debugfs_desc_done_irq_read(char * buf)304 static ssize_t xilinx_dpdma_debugfs_desc_done_irq_read(char *buf)
305 {
306 	size_t out_str_len;
307 
308 	dpdma_debugfs.testcase = DPDMA_TC_NONE;
309 
310 	out_str_len = strlen(XILINX_DPDMA_DEBUGFS_UINT16_MAX_STR);
311 	out_str_len = min_t(size_t, XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE,
312 			    out_str_len);
313 	snprintf(buf, out_str_len, "%d",
314 		 dpdma_debugfs.xilinx_dpdma_irq_done_count);
315 
316 	return 0;
317 }
318 
xilinx_dpdma_debugfs_desc_done_irq_write(char * args)319 static int xilinx_dpdma_debugfs_desc_done_irq_write(char *args)
320 {
321 	char *arg;
322 	int ret;
323 	u32 id;
324 
325 	arg = strsep(&args, " ");
326 	if (!arg || strncasecmp(arg, "start", 5))
327 		return -EINVAL;
328 
329 	arg = strsep(&args, " ");
330 	if (!arg)
331 		return -EINVAL;
332 
333 	ret = kstrtou32(arg, 0, &id);
334 	if (ret < 0)
335 		return ret;
336 
337 	if (id < ZYNQMP_DPDMA_VIDEO0 || id > ZYNQMP_DPDMA_AUDIO1)
338 		return -EINVAL;
339 
340 	dpdma_debugfs.testcase = DPDMA_TC_INTR_DONE;
341 	dpdma_debugfs.xilinx_dpdma_irq_done_count = 0;
342 	dpdma_debugfs.chan_id = id;
343 
344 	return 0;
345 }
346 
347 /* Match xilinx_dpdma_testcases vs dpdma_debugfs_reqs[] entry */
348 static struct xilinx_dpdma_debugfs_request dpdma_debugfs_reqs[] = {
349 	{
350 		.name = "DESCRIPTOR_DONE_INTR",
351 		.tc = DPDMA_TC_INTR_DONE,
352 		.read = xilinx_dpdma_debugfs_desc_done_irq_read,
353 		.write = xilinx_dpdma_debugfs_desc_done_irq_write,
354 	},
355 };
356 
xilinx_dpdma_debugfs_read(struct file * f,char __user * buf,size_t size,loff_t * pos)357 static ssize_t xilinx_dpdma_debugfs_read(struct file *f, char __user *buf,
358 					 size_t size, loff_t *pos)
359 {
360 	enum xilinx_dpdma_testcases testcase;
361 	char *kern_buff;
362 	int ret = 0;
363 
364 	if (*pos != 0 || size <= 0)
365 		return -EINVAL;
366 
367 	kern_buff = kzalloc(XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE, GFP_KERNEL);
368 	if (!kern_buff) {
369 		dpdma_debugfs.testcase = DPDMA_TC_NONE;
370 		return -ENOMEM;
371 	}
372 
373 	testcase = READ_ONCE(dpdma_debugfs.testcase);
374 	if (testcase != DPDMA_TC_NONE) {
375 		ret = dpdma_debugfs_reqs[testcase].read(kern_buff);
376 		if (ret < 0)
377 			goto done;
378 	} else {
379 		strlcpy(kern_buff, "No testcase executed",
380 			XILINX_DPDMA_DEBUGFS_READ_MAX_SIZE);
381 	}
382 
383 	size = min(size, strlen(kern_buff));
384 	if (copy_to_user(buf, kern_buff, size))
385 		ret = -EFAULT;
386 
387 done:
388 	kfree(kern_buff);
389 	if (ret)
390 		return ret;
391 
392 	*pos = size + 1;
393 	return size;
394 }
395 
xilinx_dpdma_debugfs_write(struct file * f,const char __user * buf,size_t size,loff_t * pos)396 static ssize_t xilinx_dpdma_debugfs_write(struct file *f,
397 					  const char __user *buf, size_t size,
398 					  loff_t *pos)
399 {
400 	char *kern_buff, *kern_buff_start;
401 	char *testcase;
402 	unsigned int i;
403 	int ret;
404 
405 	if (*pos != 0 || size <= 0)
406 		return -EINVAL;
407 
408 	/* Supporting single instance of test as of now. */
409 	if (dpdma_debugfs.testcase != DPDMA_TC_NONE)
410 		return -EBUSY;
411 
412 	kern_buff = kzalloc(size, GFP_KERNEL);
413 	if (!kern_buff)
414 		return -ENOMEM;
415 	kern_buff_start = kern_buff;
416 
417 	ret = strncpy_from_user(kern_buff, buf, size);
418 	if (ret < 0)
419 		goto done;
420 
421 	/* Read the testcase name from a user request. */
422 	testcase = strsep(&kern_buff, " ");
423 
424 	for (i = 0; i < ARRAY_SIZE(dpdma_debugfs_reqs); i++) {
425 		if (!strcasecmp(testcase, dpdma_debugfs_reqs[i].name))
426 			break;
427 	}
428 
429 	if (i == ARRAY_SIZE(dpdma_debugfs_reqs)) {
430 		ret = -EINVAL;
431 		goto done;
432 	}
433 
434 	ret = dpdma_debugfs_reqs[i].write(kern_buff);
435 	if (ret < 0)
436 		goto done;
437 
438 	ret = size;
439 
440 done:
441 	kfree(kern_buff_start);
442 	return ret;
443 }
444 
445 static const struct file_operations fops_xilinx_dpdma_dbgfs = {
446 	.owner = THIS_MODULE,
447 	.read = xilinx_dpdma_debugfs_read,
448 	.write = xilinx_dpdma_debugfs_write,
449 };
450 
xilinx_dpdma_debugfs_init(struct xilinx_dpdma_device * xdev)451 static void xilinx_dpdma_debugfs_init(struct xilinx_dpdma_device *xdev)
452 {
453 	struct dentry *dent;
454 
455 	dpdma_debugfs.testcase = DPDMA_TC_NONE;
456 
457 	dent = debugfs_create_file("testcase", 0444, xdev->common.dbg_dev_root,
458 				   NULL, &fops_xilinx_dpdma_dbgfs);
459 	if (IS_ERR(dent))
460 		dev_err(xdev->dev, "Failed to create debugfs testcase file\n");
461 }
462 
463 /* -----------------------------------------------------------------------------
464  * I/O Accessors
465  */
466 
dpdma_read(void __iomem * base,u32 offset)467 static inline u32 dpdma_read(void __iomem *base, u32 offset)
468 {
469 	return ioread32(base + offset);
470 }
471 
dpdma_write(void __iomem * base,u32 offset,u32 val)472 static inline void dpdma_write(void __iomem *base, u32 offset, u32 val)
473 {
474 	iowrite32(val, base + offset);
475 }
476 
dpdma_clr(void __iomem * base,u32 offset,u32 clr)477 static inline void dpdma_clr(void __iomem *base, u32 offset, u32 clr)
478 {
479 	dpdma_write(base, offset, dpdma_read(base, offset) & ~clr);
480 }
481 
dpdma_set(void __iomem * base,u32 offset,u32 set)482 static inline void dpdma_set(void __iomem *base, u32 offset, u32 set)
483 {
484 	dpdma_write(base, offset, dpdma_read(base, offset) | set);
485 }
486 
487 /* -----------------------------------------------------------------------------
488  * Descriptor Operations
489  */
490 
491 /**
492  * xilinx_dpdma_sw_desc_set_dma_addrs - Set DMA addresses in the descriptor
493  * @xdev: DPDMA device
494  * @sw_desc: The software descriptor in which to set DMA addresses
495  * @prev: The previous descriptor
496  * @dma_addr: array of dma addresses
497  * @num_src_addr: number of addresses in @dma_addr
498  *
499  * Set all the DMA addresses in the hardware descriptor corresponding to @dev
500  * from @dma_addr. If a previous descriptor is specified in @prev, its next
501  * descriptor DMA address is set to the DMA address of @sw_desc. @prev may be
502  * identical to @sw_desc for cyclic transfers.
503  */
xilinx_dpdma_sw_desc_set_dma_addrs(struct xilinx_dpdma_device * xdev,struct xilinx_dpdma_sw_desc * sw_desc,struct xilinx_dpdma_sw_desc * prev,dma_addr_t dma_addr[],unsigned int num_src_addr)504 static void xilinx_dpdma_sw_desc_set_dma_addrs(struct xilinx_dpdma_device *xdev,
505 					       struct xilinx_dpdma_sw_desc *sw_desc,
506 					       struct xilinx_dpdma_sw_desc *prev,
507 					       dma_addr_t dma_addr[],
508 					       unsigned int num_src_addr)
509 {
510 	struct xilinx_dpdma_hw_desc *hw_desc = &sw_desc->hw;
511 	unsigned int i;
512 
513 	hw_desc->src_addr = lower_32_bits(dma_addr[0]);
514 	if (xdev->ext_addr)
515 		hw_desc->addr_ext |=
516 			FIELD_PREP(XILINX_DPDMA_DESC_ADDR_EXT_SRC_ADDR_MASK,
517 				   upper_32_bits(dma_addr[0]));
518 
519 	for (i = 1; i < num_src_addr; i++) {
520 		u32 *addr = &hw_desc->src_addr2;
521 
522 		addr[i - 1] = lower_32_bits(dma_addr[i]);
523 
524 		if (xdev->ext_addr) {
525 			u32 *addr_ext = &hw_desc->addr_ext_23;
526 			u32 addr_msb;
527 
528 			addr_msb = upper_32_bits(dma_addr[i]) & GENMASK(15, 0);
529 			addr_msb <<= 16 * ((i - 1) % 2);
530 			addr_ext[(i - 1) / 2] |= addr_msb;
531 		}
532 	}
533 
534 	if (!prev)
535 		return;
536 
537 	prev->hw.next_desc = lower_32_bits(sw_desc->dma_addr);
538 	if (xdev->ext_addr)
539 		prev->hw.addr_ext |=
540 			FIELD_PREP(XILINX_DPDMA_DESC_ADDR_EXT_NEXT_ADDR_MASK,
541 				   upper_32_bits(sw_desc->dma_addr));
542 }
543 
544 /**
545  * xilinx_dpdma_chan_alloc_sw_desc - Allocate a software descriptor
546  * @chan: DPDMA channel
547  *
548  * Allocate a software descriptor from the channel's descriptor pool.
549  *
550  * Return: a software descriptor or NULL.
551  */
552 static struct xilinx_dpdma_sw_desc *
xilinx_dpdma_chan_alloc_sw_desc(struct xilinx_dpdma_chan * chan)553 xilinx_dpdma_chan_alloc_sw_desc(struct xilinx_dpdma_chan *chan)
554 {
555 	struct xilinx_dpdma_sw_desc *sw_desc;
556 	dma_addr_t dma_addr;
557 
558 	sw_desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &dma_addr);
559 	if (!sw_desc)
560 		return NULL;
561 
562 	sw_desc->dma_addr = dma_addr;
563 
564 	return sw_desc;
565 }
566 
567 /**
568  * xilinx_dpdma_chan_free_sw_desc - Free a software descriptor
569  * @chan: DPDMA channel
570  * @sw_desc: software descriptor to free
571  *
572  * Free a software descriptor from the channel's descriptor pool.
573  */
574 static void
xilinx_dpdma_chan_free_sw_desc(struct xilinx_dpdma_chan * chan,struct xilinx_dpdma_sw_desc * sw_desc)575 xilinx_dpdma_chan_free_sw_desc(struct xilinx_dpdma_chan *chan,
576 			       struct xilinx_dpdma_sw_desc *sw_desc)
577 {
578 	dma_pool_free(chan->desc_pool, sw_desc, sw_desc->dma_addr);
579 }
580 
581 /**
582  * xilinx_dpdma_chan_dump_tx_desc - Dump a tx descriptor
583  * @chan: DPDMA channel
584  * @tx_desc: tx descriptor to dump
585  *
586  * Dump contents of a tx descriptor
587  */
xilinx_dpdma_chan_dump_tx_desc(struct xilinx_dpdma_chan * chan,struct xilinx_dpdma_tx_desc * tx_desc)588 static void xilinx_dpdma_chan_dump_tx_desc(struct xilinx_dpdma_chan *chan,
589 					   struct xilinx_dpdma_tx_desc *tx_desc)
590 {
591 	struct xilinx_dpdma_sw_desc *sw_desc;
592 	struct device *dev = chan->xdev->dev;
593 	unsigned int i = 0;
594 
595 	dev_dbg(dev, "------- TX descriptor dump start -------\n");
596 	dev_dbg(dev, "------- channel ID = %d -------\n", chan->id);
597 
598 	list_for_each_entry(sw_desc, &tx_desc->descriptors, node) {
599 		struct xilinx_dpdma_hw_desc *hw_desc = &sw_desc->hw;
600 
601 		dev_dbg(dev, "------- HW descriptor %d -------\n", i++);
602 		dev_dbg(dev, "descriptor DMA addr: %pad\n", &sw_desc->dma_addr);
603 		dev_dbg(dev, "control: 0x%08x\n", hw_desc->control);
604 		dev_dbg(dev, "desc_id: 0x%08x\n", hw_desc->desc_id);
605 		dev_dbg(dev, "xfer_size: 0x%08x\n", hw_desc->xfer_size);
606 		dev_dbg(dev, "hsize_stride: 0x%08x\n", hw_desc->hsize_stride);
607 		dev_dbg(dev, "timestamp_lsb: 0x%08x\n", hw_desc->timestamp_lsb);
608 		dev_dbg(dev, "timestamp_msb: 0x%08x\n", hw_desc->timestamp_msb);
609 		dev_dbg(dev, "addr_ext: 0x%08x\n", hw_desc->addr_ext);
610 		dev_dbg(dev, "next_desc: 0x%08x\n", hw_desc->next_desc);
611 		dev_dbg(dev, "src_addr: 0x%08x\n", hw_desc->src_addr);
612 		dev_dbg(dev, "addr_ext_23: 0x%08x\n", hw_desc->addr_ext_23);
613 		dev_dbg(dev, "addr_ext_45: 0x%08x\n", hw_desc->addr_ext_45);
614 		dev_dbg(dev, "src_addr2: 0x%08x\n", hw_desc->src_addr2);
615 		dev_dbg(dev, "src_addr3: 0x%08x\n", hw_desc->src_addr3);
616 		dev_dbg(dev, "src_addr4: 0x%08x\n", hw_desc->src_addr4);
617 		dev_dbg(dev, "src_addr5: 0x%08x\n", hw_desc->src_addr5);
618 		dev_dbg(dev, "crc: 0x%08x\n", hw_desc->crc);
619 	}
620 
621 	dev_dbg(dev, "------- TX descriptor dump end -------\n");
622 }
623 
624 /**
625  * xilinx_dpdma_chan_alloc_tx_desc - Allocate a transaction descriptor
626  * @chan: DPDMA channel
627  *
628  * Allocate a tx descriptor.
629  *
630  * Return: a tx descriptor or NULL.
631  */
632 static struct xilinx_dpdma_tx_desc *
xilinx_dpdma_chan_alloc_tx_desc(struct xilinx_dpdma_chan * chan)633 xilinx_dpdma_chan_alloc_tx_desc(struct xilinx_dpdma_chan *chan)
634 {
635 	struct xilinx_dpdma_tx_desc *tx_desc;
636 
637 	tx_desc = kzalloc(sizeof(*tx_desc), GFP_NOWAIT);
638 	if (!tx_desc)
639 		return NULL;
640 
641 	INIT_LIST_HEAD(&tx_desc->descriptors);
642 	tx_desc->chan = chan;
643 	tx_desc->error = false;
644 
645 	return tx_desc;
646 }
647 
648 /**
649  * xilinx_dpdma_chan_free_tx_desc - Free a virtual DMA descriptor
650  * @vdesc: virtual DMA descriptor
651  *
652  * Free the virtual DMA descriptor @vdesc including its software descriptors.
653  */
xilinx_dpdma_chan_free_tx_desc(struct virt_dma_desc * vdesc)654 static void xilinx_dpdma_chan_free_tx_desc(struct virt_dma_desc *vdesc)
655 {
656 	struct xilinx_dpdma_sw_desc *sw_desc, *next;
657 	struct xilinx_dpdma_tx_desc *desc;
658 
659 	if (!vdesc)
660 		return;
661 
662 	desc = to_dpdma_tx_desc(vdesc);
663 
664 	list_for_each_entry_safe(sw_desc, next, &desc->descriptors, node) {
665 		list_del(&sw_desc->node);
666 		xilinx_dpdma_chan_free_sw_desc(desc->chan, sw_desc);
667 	}
668 
669 	kfree(desc);
670 }
671 
672 /**
673  * xilinx_dpdma_chan_prep_interleaved_dma - Prepare an interleaved dma
674  *					    descriptor
675  * @chan: DPDMA channel
676  * @xt: dma interleaved template
677  *
678  * Prepare a tx descriptor including internal software/hardware descriptors
679  * based on @xt.
680  *
681  * Return: A DPDMA TX descriptor on success, or NULL.
682  */
683 static struct xilinx_dpdma_tx_desc *
xilinx_dpdma_chan_prep_interleaved_dma(struct xilinx_dpdma_chan * chan,struct dma_interleaved_template * xt)684 xilinx_dpdma_chan_prep_interleaved_dma(struct xilinx_dpdma_chan *chan,
685 				       struct dma_interleaved_template *xt)
686 {
687 	struct xilinx_dpdma_tx_desc *tx_desc;
688 	struct xilinx_dpdma_sw_desc *sw_desc;
689 	struct xilinx_dpdma_hw_desc *hw_desc;
690 	size_t hsize = xt->sgl[0].size;
691 	size_t stride = hsize + xt->sgl[0].icg;
692 
693 	if (!IS_ALIGNED(xt->src_start, XILINX_DPDMA_ALIGN_BYTES)) {
694 		dev_err(chan->xdev->dev,
695 			"chan%u: buffer should be aligned at %d B\n",
696 			chan->id, XILINX_DPDMA_ALIGN_BYTES);
697 		return NULL;
698 	}
699 
700 	tx_desc = xilinx_dpdma_chan_alloc_tx_desc(chan);
701 	if (!tx_desc)
702 		return NULL;
703 
704 	sw_desc = xilinx_dpdma_chan_alloc_sw_desc(chan);
705 	if (!sw_desc) {
706 		xilinx_dpdma_chan_free_tx_desc(&tx_desc->vdesc);
707 		return NULL;
708 	}
709 
710 	xilinx_dpdma_sw_desc_set_dma_addrs(chan->xdev, sw_desc, sw_desc,
711 					   &xt->src_start, 1);
712 
713 	hw_desc = &sw_desc->hw;
714 	hsize = ALIGN(hsize, XILINX_DPDMA_LINESIZE_ALIGN_BITS / 8);
715 	hw_desc->xfer_size = hsize * xt->numf;
716 	hw_desc->hsize_stride =
717 		FIELD_PREP(XILINX_DPDMA_DESC_HSIZE_STRIDE_HSIZE_MASK, hsize) |
718 		FIELD_PREP(XILINX_DPDMA_DESC_HSIZE_STRIDE_STRIDE_MASK,
719 			   stride / 16);
720 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_PREEMBLE;
721 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_COMPLETE_INTR;
722 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_IGNORE_DONE;
723 	hw_desc->control |= XILINX_DPDMA_DESC_CONTROL_LAST_OF_FRAME;
724 
725 	list_add_tail(&sw_desc->node, &tx_desc->descriptors);
726 
727 	return tx_desc;
728 }
729 
730 /* -----------------------------------------------------------------------------
731  * DPDMA Channel Operations
732  */
733 
734 /**
735  * xilinx_dpdma_chan_enable - Enable the channel
736  * @chan: DPDMA channel
737  *
738  * Enable the channel and its interrupts. Set the QoS values for video class.
739  */
xilinx_dpdma_chan_enable(struct xilinx_dpdma_chan * chan)740 static void xilinx_dpdma_chan_enable(struct xilinx_dpdma_chan *chan)
741 {
742 	u32 reg;
743 
744 	reg = (XILINX_DPDMA_INTR_CHAN_MASK << chan->id)
745 	    | XILINX_DPDMA_INTR_GLOBAL_MASK;
746 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN, reg);
747 	reg = (XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id)
748 	    | XILINX_DPDMA_INTR_GLOBAL_ERR;
749 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_EIEN, reg);
750 
751 	reg = XILINX_DPDMA_CH_CNTL_ENABLE
752 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DSCR_WR_MASK,
753 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS)
754 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DSCR_RD_MASK,
755 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS)
756 	    | FIELD_PREP(XILINX_DPDMA_CH_CNTL_QOS_DATA_RD_MASK,
757 			 XILINX_DPDMA_CH_CNTL_QOS_VID_CLASS);
758 	dpdma_set(chan->reg, XILINX_DPDMA_CH_CNTL, reg);
759 }
760 
761 /**
762  * xilinx_dpdma_chan_disable - Disable the channel
763  * @chan: DPDMA channel
764  *
765  * Disable the channel and its interrupts.
766  */
xilinx_dpdma_chan_disable(struct xilinx_dpdma_chan * chan)767 static void xilinx_dpdma_chan_disable(struct xilinx_dpdma_chan *chan)
768 {
769 	u32 reg;
770 
771 	reg = XILINX_DPDMA_INTR_CHAN_MASK << chan->id;
772 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN, reg);
773 	reg = XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id;
774 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_EIEN, reg);
775 
776 	dpdma_clr(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_ENABLE);
777 }
778 
779 /**
780  * xilinx_dpdma_chan_pause - Pause the channel
781  * @chan: DPDMA channel
782  *
783  * Pause the channel.
784  */
xilinx_dpdma_chan_pause(struct xilinx_dpdma_chan * chan)785 static void xilinx_dpdma_chan_pause(struct xilinx_dpdma_chan *chan)
786 {
787 	dpdma_set(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_PAUSE);
788 }
789 
790 /**
791  * xilinx_dpdma_chan_unpause - Unpause the channel
792  * @chan: DPDMA channel
793  *
794  * Unpause the channel.
795  */
xilinx_dpdma_chan_unpause(struct xilinx_dpdma_chan * chan)796 static void xilinx_dpdma_chan_unpause(struct xilinx_dpdma_chan *chan)
797 {
798 	dpdma_clr(chan->reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_PAUSE);
799 }
800 
xilinx_dpdma_chan_video_group_ready(struct xilinx_dpdma_chan * chan)801 static u32 xilinx_dpdma_chan_video_group_ready(struct xilinx_dpdma_chan *chan)
802 {
803 	struct xilinx_dpdma_device *xdev = chan->xdev;
804 	u32 channels = 0;
805 	unsigned int i;
806 
807 	for (i = ZYNQMP_DPDMA_VIDEO0; i <= ZYNQMP_DPDMA_VIDEO2; i++) {
808 		if (xdev->chan[i]->video_group && !xdev->chan[i]->running)
809 			return 0;
810 
811 		if (xdev->chan[i]->video_group)
812 			channels |= BIT(i);
813 	}
814 
815 	return channels;
816 }
817 
818 /**
819  * xilinx_dpdma_chan_queue_transfer - Queue the next transfer
820  * @chan: DPDMA channel
821  *
822  * Queue the next descriptor, if any, to the hardware. If the channel is
823  * stopped, start it first. Otherwise retrigger it with the next descriptor.
824  */
xilinx_dpdma_chan_queue_transfer(struct xilinx_dpdma_chan * chan)825 static void xilinx_dpdma_chan_queue_transfer(struct xilinx_dpdma_chan *chan)
826 {
827 	struct xilinx_dpdma_device *xdev = chan->xdev;
828 	struct xilinx_dpdma_sw_desc *sw_desc;
829 	struct xilinx_dpdma_tx_desc *desc;
830 	struct virt_dma_desc *vdesc;
831 	u32 reg, channels;
832 	bool first_frame;
833 
834 	lockdep_assert_held(&chan->lock);
835 
836 	if (chan->desc.pending)
837 		return;
838 
839 	if (!chan->running) {
840 		xilinx_dpdma_chan_unpause(chan);
841 		xilinx_dpdma_chan_enable(chan);
842 		chan->first_frame = true;
843 		chan->running = true;
844 	}
845 
846 	vdesc = vchan_next_desc(&chan->vchan);
847 	if (!vdesc)
848 		return;
849 
850 	desc = to_dpdma_tx_desc(vdesc);
851 	chan->desc.pending = desc;
852 	list_del(&desc->vdesc.node);
853 
854 	/*
855 	 * Assign the cookie to descriptors in this transaction. Only 16 bit
856 	 * will be used, but it should be enough.
857 	 */
858 	list_for_each_entry(sw_desc, &desc->descriptors, node)
859 		sw_desc->hw.desc_id = desc->vdesc.tx.cookie
860 				    & XILINX_DPDMA_CH_DESC_ID_MASK;
861 
862 	sw_desc = list_first_entry(&desc->descriptors,
863 				   struct xilinx_dpdma_sw_desc, node);
864 	dpdma_write(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDR,
865 		    lower_32_bits(sw_desc->dma_addr));
866 	if (xdev->ext_addr)
867 		dpdma_write(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDRE,
868 			    FIELD_PREP(XILINX_DPDMA_CH_DESC_START_ADDRE_MASK,
869 				       upper_32_bits(sw_desc->dma_addr)));
870 
871 	first_frame = chan->first_frame;
872 	chan->first_frame = false;
873 
874 	if (chan->video_group) {
875 		channels = xilinx_dpdma_chan_video_group_ready(chan);
876 		/*
877 		 * Trigger the transfer only when all channels in the group are
878 		 * ready.
879 		 */
880 		if (!channels)
881 			return;
882 	} else {
883 		channels = BIT(chan->id);
884 	}
885 
886 	if (first_frame)
887 		reg = XILINX_DPDMA_GBL_TRIG_MASK(channels);
888 	else
889 		reg = XILINX_DPDMA_GBL_RETRIG_MASK(channels);
890 
891 	dpdma_write(xdev->reg, XILINX_DPDMA_GBL, reg);
892 }
893 
894 /**
895  * xilinx_dpdma_chan_ostand - Number of outstanding transactions
896  * @chan: DPDMA channel
897  *
898  * Read and return the number of outstanding transactions from register.
899  *
900  * Return: Number of outstanding transactions from the status register.
901  */
xilinx_dpdma_chan_ostand(struct xilinx_dpdma_chan * chan)902 static u32 xilinx_dpdma_chan_ostand(struct xilinx_dpdma_chan *chan)
903 {
904 	return FIELD_GET(XILINX_DPDMA_CH_STATUS_OTRAN_CNT_MASK,
905 			 dpdma_read(chan->reg, XILINX_DPDMA_CH_STATUS));
906 }
907 
908 /**
909  * xilinx_dpdma_chan_notify_no_ostand - Notify no outstanding transaction event
910  * @chan: DPDMA channel
911  *
912  * Notify waiters for no outstanding event, so waiters can stop the channel
913  * safely. This function is supposed to be called when 'no outstanding'
914  * interrupt is generated. The 'no outstanding' interrupt is disabled and
915  * should be re-enabled when this event is handled. If the channel status
916  * register still shows some number of outstanding transactions, the interrupt
917  * remains enabled.
918  *
919  * Return: 0 on success. On failure, -EWOULDBLOCK if there's still outstanding
920  * transaction(s).
921  */
xilinx_dpdma_chan_notify_no_ostand(struct xilinx_dpdma_chan * chan)922 static int xilinx_dpdma_chan_notify_no_ostand(struct xilinx_dpdma_chan *chan)
923 {
924 	u32 cnt;
925 
926 	cnt = xilinx_dpdma_chan_ostand(chan);
927 	if (cnt) {
928 		dev_dbg(chan->xdev->dev,
929 			"chan%u: %d outstanding transactions\n",
930 			chan->id, cnt);
931 		return -EWOULDBLOCK;
932 	}
933 
934 	/* Disable 'no outstanding' interrupt */
935 	dpdma_write(chan->xdev->reg, XILINX_DPDMA_IDS,
936 		    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
937 	wake_up(&chan->wait_to_stop);
938 
939 	return 0;
940 }
941 
942 /**
943  * xilinx_dpdma_chan_wait_no_ostand - Wait for the no outstanding irq
944  * @chan: DPDMA channel
945  *
946  * Wait for the no outstanding transaction interrupt. This functions can sleep
947  * for 50ms.
948  *
949  * Return: 0 on success. On failure, -ETIMEOUT for time out, or the error code
950  * from wait_event_interruptible_timeout().
951  */
xilinx_dpdma_chan_wait_no_ostand(struct xilinx_dpdma_chan * chan)952 static int xilinx_dpdma_chan_wait_no_ostand(struct xilinx_dpdma_chan *chan)
953 {
954 	int ret;
955 
956 	/* Wait for a no outstanding transaction interrupt upto 50msec */
957 	ret = wait_event_interruptible_timeout(chan->wait_to_stop,
958 					       !xilinx_dpdma_chan_ostand(chan),
959 					       msecs_to_jiffies(50));
960 	if (ret > 0) {
961 		dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN,
962 			    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
963 		return 0;
964 	}
965 
966 	dev_err(chan->xdev->dev, "chan%u: not ready to stop: %d trans\n",
967 		chan->id, xilinx_dpdma_chan_ostand(chan));
968 
969 	if (ret == 0)
970 		return -ETIMEDOUT;
971 
972 	return ret;
973 }
974 
975 /**
976  * xilinx_dpdma_chan_poll_no_ostand - Poll the outstanding transaction status
977  * @chan: DPDMA channel
978  *
979  * Poll the outstanding transaction status, and return when there's no
980  * outstanding transaction. This functions can be used in the interrupt context
981  * or where the atomicity is required. Calling thread may wait more than 50ms.
982  *
983  * Return: 0 on success, or -ETIMEDOUT.
984  */
xilinx_dpdma_chan_poll_no_ostand(struct xilinx_dpdma_chan * chan)985 static int xilinx_dpdma_chan_poll_no_ostand(struct xilinx_dpdma_chan *chan)
986 {
987 	u32 cnt, loop = 50000;
988 
989 	/* Poll at least for 50ms (20 fps). */
990 	do {
991 		cnt = xilinx_dpdma_chan_ostand(chan);
992 		udelay(1);
993 	} while (loop-- > 0 && cnt);
994 
995 	if (loop) {
996 		dpdma_write(chan->xdev->reg, XILINX_DPDMA_IEN,
997 			    XILINX_DPDMA_INTR_NO_OSTAND(chan->id));
998 		return 0;
999 	}
1000 
1001 	dev_err(chan->xdev->dev, "chan%u: not ready to stop: %d trans\n",
1002 		chan->id, xilinx_dpdma_chan_ostand(chan));
1003 
1004 	return -ETIMEDOUT;
1005 }
1006 
1007 /**
1008  * xilinx_dpdma_chan_stop - Stop the channel
1009  * @chan: DPDMA channel
1010  *
1011  * Stop a previously paused channel by first waiting for completion of all
1012  * outstanding transaction and then disabling the channel.
1013  *
1014  * Return: 0 on success, or -ETIMEDOUT if the channel failed to stop.
1015  */
xilinx_dpdma_chan_stop(struct xilinx_dpdma_chan * chan)1016 static int xilinx_dpdma_chan_stop(struct xilinx_dpdma_chan *chan)
1017 {
1018 	unsigned long flags;
1019 	int ret;
1020 
1021 	ret = xilinx_dpdma_chan_wait_no_ostand(chan);
1022 	if (ret)
1023 		return ret;
1024 
1025 	spin_lock_irqsave(&chan->lock, flags);
1026 	xilinx_dpdma_chan_disable(chan);
1027 	chan->running = false;
1028 	spin_unlock_irqrestore(&chan->lock, flags);
1029 
1030 	return 0;
1031 }
1032 
1033 /**
1034  * xilinx_dpdma_chan_done_irq - Handle hardware descriptor completion
1035  * @chan: DPDMA channel
1036  *
1037  * Handle completion of the currently active descriptor (@chan->desc.active). As
1038  * we currently support cyclic transfers only, this just invokes the cyclic
1039  * callback. The descriptor will be completed at the VSYNC interrupt when a new
1040  * descriptor replaces it.
1041  */
xilinx_dpdma_chan_done_irq(struct xilinx_dpdma_chan * chan)1042 static void xilinx_dpdma_chan_done_irq(struct xilinx_dpdma_chan *chan)
1043 {
1044 	struct xilinx_dpdma_tx_desc *active;
1045 	unsigned long flags;
1046 
1047 	spin_lock_irqsave(&chan->lock, flags);
1048 
1049 	xilinx_dpdma_debugfs_desc_done_irq(chan);
1050 
1051 	active = chan->desc.active;
1052 	if (active)
1053 		vchan_cyclic_callback(&active->vdesc);
1054 	else
1055 		dev_warn(chan->xdev->dev,
1056 			 "chan%u: DONE IRQ with no active descriptor!\n",
1057 			 chan->id);
1058 
1059 	spin_unlock_irqrestore(&chan->lock, flags);
1060 }
1061 
1062 /**
1063  * xilinx_dpdma_chan_vsync_irq - Handle hardware descriptor scheduling
1064  * @chan: DPDMA channel
1065  *
1066  * At VSYNC the active descriptor may have been replaced by the pending
1067  * descriptor. Detect this through the DESC_ID and perform appropriate
1068  * bookkeeping.
1069  */
xilinx_dpdma_chan_vsync_irq(struct xilinx_dpdma_chan * chan)1070 static void xilinx_dpdma_chan_vsync_irq(struct  xilinx_dpdma_chan *chan)
1071 {
1072 	struct xilinx_dpdma_tx_desc *pending;
1073 	struct xilinx_dpdma_sw_desc *sw_desc;
1074 	unsigned long flags;
1075 	u32 desc_id;
1076 
1077 	spin_lock_irqsave(&chan->lock, flags);
1078 
1079 	pending = chan->desc.pending;
1080 	if (!chan->running || !pending)
1081 		goto out;
1082 
1083 	desc_id = dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_ID)
1084 		& XILINX_DPDMA_CH_DESC_ID_MASK;
1085 
1086 	/* If the retrigger raced with vsync, retry at the next frame. */
1087 	sw_desc = list_first_entry(&pending->descriptors,
1088 				   struct xilinx_dpdma_sw_desc, node);
1089 	if (sw_desc->hw.desc_id != desc_id) {
1090 		dev_dbg(chan->xdev->dev,
1091 			"chan%u: vsync race lost (%u != %u), retrying\n",
1092 			chan->id, sw_desc->hw.desc_id, desc_id);
1093 		goto out;
1094 	}
1095 
1096 	/*
1097 	 * Complete the active descriptor, if any, promote the pending
1098 	 * descriptor to active, and queue the next transfer, if any.
1099 	 */
1100 	if (chan->desc.active)
1101 		vchan_cookie_complete(&chan->desc.active->vdesc);
1102 	chan->desc.active = pending;
1103 	chan->desc.pending = NULL;
1104 
1105 	xilinx_dpdma_chan_queue_transfer(chan);
1106 
1107 out:
1108 	spin_unlock_irqrestore(&chan->lock, flags);
1109 }
1110 
1111 /**
1112  * xilinx_dpdma_chan_err - Detect any channel error
1113  * @chan: DPDMA channel
1114  * @isr: masked Interrupt Status Register
1115  * @eisr: Error Interrupt Status Register
1116  *
1117  * Return: true if any channel error occurs, or false otherwise.
1118  */
1119 static bool
xilinx_dpdma_chan_err(struct xilinx_dpdma_chan * chan,u32 isr,u32 eisr)1120 xilinx_dpdma_chan_err(struct xilinx_dpdma_chan *chan, u32 isr, u32 eisr)
1121 {
1122 	if (!chan)
1123 		return false;
1124 
1125 	if (chan->running &&
1126 	    ((isr & (XILINX_DPDMA_INTR_CHAN_ERR_MASK << chan->id)) ||
1127 	    (eisr & (XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id))))
1128 		return true;
1129 
1130 	return false;
1131 }
1132 
1133 /**
1134  * xilinx_dpdma_chan_handle_err - DPDMA channel error handling
1135  * @chan: DPDMA channel
1136  *
1137  * This function is called when any channel error or any global error occurs.
1138  * The function disables the paused channel by errors and determines
1139  * if the current active descriptor can be rescheduled depending on
1140  * the descriptor status.
1141  */
xilinx_dpdma_chan_handle_err(struct xilinx_dpdma_chan * chan)1142 static void xilinx_dpdma_chan_handle_err(struct xilinx_dpdma_chan *chan)
1143 {
1144 	struct xilinx_dpdma_device *xdev = chan->xdev;
1145 	struct xilinx_dpdma_tx_desc *active;
1146 	unsigned long flags;
1147 
1148 	spin_lock_irqsave(&chan->lock, flags);
1149 
1150 	dev_dbg(xdev->dev, "chan%u: cur desc addr = 0x%04x%08x\n",
1151 		chan->id,
1152 		dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDRE),
1153 		dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_START_ADDR));
1154 	dev_dbg(xdev->dev, "chan%u: cur payload addr = 0x%04x%08x\n",
1155 		chan->id,
1156 		dpdma_read(chan->reg, XILINX_DPDMA_CH_PYLD_CUR_ADDRE),
1157 		dpdma_read(chan->reg, XILINX_DPDMA_CH_PYLD_CUR_ADDR));
1158 
1159 	xilinx_dpdma_chan_disable(chan);
1160 	chan->running = false;
1161 
1162 	if (!chan->desc.active)
1163 		goto out_unlock;
1164 
1165 	active = chan->desc.active;
1166 	chan->desc.active = NULL;
1167 
1168 	xilinx_dpdma_chan_dump_tx_desc(chan, active);
1169 
1170 	if (active->error)
1171 		dev_dbg(xdev->dev, "chan%u: repeated error on desc\n",
1172 			chan->id);
1173 
1174 	/* Reschedule if there's no new descriptor */
1175 	if (!chan->desc.pending &&
1176 	    list_empty(&chan->vchan.desc_issued)) {
1177 		active->error = true;
1178 		list_add_tail(&active->vdesc.node,
1179 			      &chan->vchan.desc_issued);
1180 	} else {
1181 		xilinx_dpdma_chan_free_tx_desc(&active->vdesc);
1182 	}
1183 
1184 out_unlock:
1185 	spin_unlock_irqrestore(&chan->lock, flags);
1186 }
1187 
1188 /* -----------------------------------------------------------------------------
1189  * DMA Engine Operations
1190  */
1191 
1192 static struct dma_async_tx_descriptor *
xilinx_dpdma_prep_interleaved_dma(struct dma_chan * dchan,struct dma_interleaved_template * xt,unsigned long flags)1193 xilinx_dpdma_prep_interleaved_dma(struct dma_chan *dchan,
1194 				  struct dma_interleaved_template *xt,
1195 				  unsigned long flags)
1196 {
1197 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1198 	struct xilinx_dpdma_tx_desc *desc;
1199 
1200 	if (xt->dir != DMA_MEM_TO_DEV)
1201 		return NULL;
1202 
1203 	if (!xt->numf || !xt->sgl[0].size)
1204 		return NULL;
1205 
1206 	if (!(flags & DMA_PREP_REPEAT) || !(flags & DMA_PREP_LOAD_EOT))
1207 		return NULL;
1208 
1209 	desc = xilinx_dpdma_chan_prep_interleaved_dma(chan, xt);
1210 	if (!desc)
1211 		return NULL;
1212 
1213 	vchan_tx_prep(&chan->vchan, &desc->vdesc, flags | DMA_CTRL_ACK);
1214 
1215 	return &desc->vdesc.tx;
1216 }
1217 
1218 /**
1219  * xilinx_dpdma_alloc_chan_resources - Allocate resources for the channel
1220  * @dchan: DMA channel
1221  *
1222  * Allocate a descriptor pool for the channel.
1223  *
1224  * Return: 0 on success, or -ENOMEM if failed to allocate a pool.
1225  */
xilinx_dpdma_alloc_chan_resources(struct dma_chan * dchan)1226 static int xilinx_dpdma_alloc_chan_resources(struct dma_chan *dchan)
1227 {
1228 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1229 	size_t align = __alignof__(struct xilinx_dpdma_sw_desc);
1230 
1231 	chan->desc_pool = dma_pool_create(dev_name(chan->xdev->dev),
1232 					  chan->xdev->dev,
1233 					  sizeof(struct xilinx_dpdma_sw_desc),
1234 					  align, 0);
1235 	if (!chan->desc_pool) {
1236 		dev_err(chan->xdev->dev,
1237 			"chan%u: failed to allocate a descriptor pool\n",
1238 			chan->id);
1239 		return -ENOMEM;
1240 	}
1241 
1242 	return 0;
1243 }
1244 
1245 /**
1246  * xilinx_dpdma_free_chan_resources - Free all resources for the channel
1247  * @dchan: DMA channel
1248  *
1249  * Free resources associated with the virtual DMA channel, and destroy the
1250  * descriptor pool.
1251  */
xilinx_dpdma_free_chan_resources(struct dma_chan * dchan)1252 static void xilinx_dpdma_free_chan_resources(struct dma_chan *dchan)
1253 {
1254 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1255 
1256 	vchan_free_chan_resources(&chan->vchan);
1257 
1258 	dma_pool_destroy(chan->desc_pool);
1259 	chan->desc_pool = NULL;
1260 }
1261 
xilinx_dpdma_issue_pending(struct dma_chan * dchan)1262 static void xilinx_dpdma_issue_pending(struct dma_chan *dchan)
1263 {
1264 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1265 	unsigned long flags;
1266 
1267 	spin_lock_irqsave(&chan->vchan.lock, flags);
1268 	if (vchan_issue_pending(&chan->vchan))
1269 		xilinx_dpdma_chan_queue_transfer(chan);
1270 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1271 }
1272 
xilinx_dpdma_config(struct dma_chan * dchan,struct dma_slave_config * config)1273 static int xilinx_dpdma_config(struct dma_chan *dchan,
1274 			       struct dma_slave_config *config)
1275 {
1276 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1277 	struct xilinx_dpdma_peripheral_config *pconfig;
1278 	unsigned long flags;
1279 
1280 	/*
1281 	 * The destination address doesn't need to be specified as the DPDMA is
1282 	 * hardwired to the destination (the DP controller). The transfer
1283 	 * width, burst size and port window size are thus meaningless, they're
1284 	 * fixed both on the DPDMA side and on the DP controller side.
1285 	 */
1286 
1287 	/*
1288 	 * Use the peripheral_config to indicate that the channel is part
1289 	 * of a video group. This requires matching use of the custom
1290 	 * structure in each driver.
1291 	 */
1292 	pconfig = config->peripheral_config;
1293 	if (WARN_ON(pconfig && config->peripheral_size != sizeof(*pconfig)))
1294 		return -EINVAL;
1295 
1296 	spin_lock_irqsave(&chan->lock, flags);
1297 	if (chan->id <= ZYNQMP_DPDMA_VIDEO2 && pconfig)
1298 		chan->video_group = pconfig->video_group;
1299 	spin_unlock_irqrestore(&chan->lock, flags);
1300 
1301 	return 0;
1302 }
1303 
xilinx_dpdma_pause(struct dma_chan * dchan)1304 static int xilinx_dpdma_pause(struct dma_chan *dchan)
1305 {
1306 	xilinx_dpdma_chan_pause(to_xilinx_chan(dchan));
1307 
1308 	return 0;
1309 }
1310 
xilinx_dpdma_resume(struct dma_chan * dchan)1311 static int xilinx_dpdma_resume(struct dma_chan *dchan)
1312 {
1313 	xilinx_dpdma_chan_unpause(to_xilinx_chan(dchan));
1314 
1315 	return 0;
1316 }
1317 
1318 /**
1319  * xilinx_dpdma_terminate_all - Terminate the channel and descriptors
1320  * @dchan: DMA channel
1321  *
1322  * Pause the channel without waiting for ongoing transfers to complete. Waiting
1323  * for completion is performed by xilinx_dpdma_synchronize() that will disable
1324  * the channel to complete the stop.
1325  *
1326  * All the descriptors associated with the channel that are guaranteed not to
1327  * be touched by the hardware. The pending and active descriptor are not
1328  * touched, and will be freed either upon completion, or by
1329  * xilinx_dpdma_synchronize().
1330  *
1331  * Return: 0 on success, or -ETIMEDOUT if the channel failed to stop.
1332  */
xilinx_dpdma_terminate_all(struct dma_chan * dchan)1333 static int xilinx_dpdma_terminate_all(struct dma_chan *dchan)
1334 {
1335 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1336 	struct xilinx_dpdma_device *xdev = chan->xdev;
1337 	LIST_HEAD(descriptors);
1338 	unsigned long flags;
1339 	unsigned int i;
1340 
1341 	/* Pause the channel (including the whole video group if applicable). */
1342 	if (chan->video_group) {
1343 		for (i = ZYNQMP_DPDMA_VIDEO0; i <= ZYNQMP_DPDMA_VIDEO2; i++) {
1344 			if (xdev->chan[i]->video_group &&
1345 			    xdev->chan[i]->running) {
1346 				xilinx_dpdma_chan_pause(xdev->chan[i]);
1347 				xdev->chan[i]->video_group = false;
1348 			}
1349 		}
1350 	} else {
1351 		xilinx_dpdma_chan_pause(chan);
1352 	}
1353 
1354 	/* Gather all the descriptors we can free and free them. */
1355 	spin_lock_irqsave(&chan->vchan.lock, flags);
1356 	vchan_get_all_descriptors(&chan->vchan, &descriptors);
1357 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1358 
1359 	vchan_dma_desc_free_list(&chan->vchan, &descriptors);
1360 
1361 	return 0;
1362 }
1363 
1364 /**
1365  * xilinx_dpdma_synchronize - Synchronize callback execution
1366  * @dchan: DMA channel
1367  *
1368  * Synchronizing callback execution ensures that all previously issued
1369  * transfers have completed and all associated callbacks have been called and
1370  * have returned.
1371  *
1372  * This function waits for the DMA channel to stop. It assumes it has been
1373  * paused by a previous call to dmaengine_terminate_async(), and that no new
1374  * pending descriptors have been issued with dma_async_issue_pending(). The
1375  * behaviour is undefined otherwise.
1376  */
xilinx_dpdma_synchronize(struct dma_chan * dchan)1377 static void xilinx_dpdma_synchronize(struct dma_chan *dchan)
1378 {
1379 	struct xilinx_dpdma_chan *chan = to_xilinx_chan(dchan);
1380 	unsigned long flags;
1381 
1382 	xilinx_dpdma_chan_stop(chan);
1383 
1384 	spin_lock_irqsave(&chan->vchan.lock, flags);
1385 	if (chan->desc.pending) {
1386 		vchan_terminate_vdesc(&chan->desc.pending->vdesc);
1387 		chan->desc.pending = NULL;
1388 	}
1389 	if (chan->desc.active) {
1390 		vchan_terminate_vdesc(&chan->desc.active->vdesc);
1391 		chan->desc.active = NULL;
1392 	}
1393 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
1394 
1395 	vchan_synchronize(&chan->vchan);
1396 }
1397 
1398 /* -----------------------------------------------------------------------------
1399  * Interrupt and Tasklet Handling
1400  */
1401 
1402 /**
1403  * xilinx_dpdma_err - Detect any global error
1404  * @isr: Interrupt Status Register
1405  * @eisr: Error Interrupt Status Register
1406  *
1407  * Return: True if any global error occurs, or false otherwise.
1408  */
xilinx_dpdma_err(u32 isr,u32 eisr)1409 static bool xilinx_dpdma_err(u32 isr, u32 eisr)
1410 {
1411 	if (isr & XILINX_DPDMA_INTR_GLOBAL_ERR ||
1412 	    eisr & XILINX_DPDMA_EINTR_GLOBAL_ERR)
1413 		return true;
1414 
1415 	return false;
1416 }
1417 
1418 /**
1419  * xilinx_dpdma_handle_err_irq - Handle DPDMA error interrupt
1420  * @xdev: DPDMA device
1421  * @isr: masked Interrupt Status Register
1422  * @eisr: Error Interrupt Status Register
1423  *
1424  * Handle if any error occurs based on @isr and @eisr. This function disables
1425  * corresponding error interrupts, and those should be re-enabled once handling
1426  * is done.
1427  */
xilinx_dpdma_handle_err_irq(struct xilinx_dpdma_device * xdev,u32 isr,u32 eisr)1428 static void xilinx_dpdma_handle_err_irq(struct xilinx_dpdma_device *xdev,
1429 					u32 isr, u32 eisr)
1430 {
1431 	bool err = xilinx_dpdma_err(isr, eisr);
1432 	unsigned int i;
1433 
1434 	dev_dbg_ratelimited(xdev->dev,
1435 			    "error irq: isr = 0x%08x, eisr = 0x%08x\n",
1436 			    isr, eisr);
1437 
1438 	/* Disable channel error interrupts until errors are handled. */
1439 	dpdma_write(xdev->reg, XILINX_DPDMA_IDS,
1440 		    isr & ~XILINX_DPDMA_INTR_GLOBAL_ERR);
1441 	dpdma_write(xdev->reg, XILINX_DPDMA_EIDS,
1442 		    eisr & ~XILINX_DPDMA_EINTR_GLOBAL_ERR);
1443 
1444 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1445 		if (err || xilinx_dpdma_chan_err(xdev->chan[i], isr, eisr))
1446 			tasklet_schedule(&xdev->chan[i]->err_task);
1447 }
1448 
1449 /**
1450  * xilinx_dpdma_enable_irq - Enable interrupts
1451  * @xdev: DPDMA device
1452  *
1453  * Enable interrupts.
1454  */
xilinx_dpdma_enable_irq(struct xilinx_dpdma_device * xdev)1455 static void xilinx_dpdma_enable_irq(struct xilinx_dpdma_device *xdev)
1456 {
1457 	dpdma_write(xdev->reg, XILINX_DPDMA_IEN, XILINX_DPDMA_INTR_ALL);
1458 	dpdma_write(xdev->reg, XILINX_DPDMA_EIEN, XILINX_DPDMA_EINTR_ALL);
1459 }
1460 
1461 /**
1462  * xilinx_dpdma_disable_irq - Disable interrupts
1463  * @xdev: DPDMA device
1464  *
1465  * Disable interrupts.
1466  */
xilinx_dpdma_disable_irq(struct xilinx_dpdma_device * xdev)1467 static void xilinx_dpdma_disable_irq(struct xilinx_dpdma_device *xdev)
1468 {
1469 	dpdma_write(xdev->reg, XILINX_DPDMA_IDS, XILINX_DPDMA_INTR_ALL);
1470 	dpdma_write(xdev->reg, XILINX_DPDMA_EIDS, XILINX_DPDMA_EINTR_ALL);
1471 }
1472 
1473 /**
1474  * xilinx_dpdma_chan_err_task - Per channel tasklet for error handling
1475  * @t: pointer to the tasklet associated with this handler
1476  *
1477  * Per channel error handling tasklet. This function waits for the outstanding
1478  * transaction to complete and triggers error handling. After error handling,
1479  * re-enable channel error interrupts, and restart the channel if needed.
1480  */
xilinx_dpdma_chan_err_task(struct tasklet_struct * t)1481 static void xilinx_dpdma_chan_err_task(struct tasklet_struct *t)
1482 {
1483 	struct xilinx_dpdma_chan *chan = from_tasklet(chan, t, err_task);
1484 	struct xilinx_dpdma_device *xdev = chan->xdev;
1485 	unsigned long flags;
1486 
1487 	/* Proceed error handling even when polling fails. */
1488 	xilinx_dpdma_chan_poll_no_ostand(chan);
1489 
1490 	xilinx_dpdma_chan_handle_err(chan);
1491 
1492 	dpdma_write(xdev->reg, XILINX_DPDMA_IEN,
1493 		    XILINX_DPDMA_INTR_CHAN_ERR_MASK << chan->id);
1494 	dpdma_write(xdev->reg, XILINX_DPDMA_EIEN,
1495 		    XILINX_DPDMA_EINTR_CHAN_ERR_MASK << chan->id);
1496 
1497 	spin_lock_irqsave(&chan->lock, flags);
1498 	xilinx_dpdma_chan_queue_transfer(chan);
1499 	spin_unlock_irqrestore(&chan->lock, flags);
1500 }
1501 
xilinx_dpdma_irq_handler(int irq,void * data)1502 static irqreturn_t xilinx_dpdma_irq_handler(int irq, void *data)
1503 {
1504 	struct xilinx_dpdma_device *xdev = data;
1505 	unsigned long mask;
1506 	unsigned int i;
1507 	u32 status;
1508 	u32 error;
1509 
1510 	status = dpdma_read(xdev->reg, XILINX_DPDMA_ISR);
1511 	error = dpdma_read(xdev->reg, XILINX_DPDMA_EISR);
1512 	if (!status && !error)
1513 		return IRQ_NONE;
1514 
1515 	dpdma_write(xdev->reg, XILINX_DPDMA_ISR, status);
1516 	dpdma_write(xdev->reg, XILINX_DPDMA_EISR, error);
1517 
1518 	if (status & XILINX_DPDMA_INTR_VSYNC) {
1519 		/*
1520 		 * There's a single VSYNC interrupt that needs to be processed
1521 		 * by each running channel to update the active descriptor.
1522 		 */
1523 		for (i = 0; i < ARRAY_SIZE(xdev->chan); i++) {
1524 			struct xilinx_dpdma_chan *chan = xdev->chan[i];
1525 
1526 			if (chan)
1527 				xilinx_dpdma_chan_vsync_irq(chan);
1528 		}
1529 	}
1530 
1531 	mask = FIELD_GET(XILINX_DPDMA_INTR_DESC_DONE_MASK, status);
1532 	if (mask) {
1533 		for_each_set_bit(i, &mask, ARRAY_SIZE(xdev->chan))
1534 			xilinx_dpdma_chan_done_irq(xdev->chan[i]);
1535 	}
1536 
1537 	mask = FIELD_GET(XILINX_DPDMA_INTR_NO_OSTAND_MASK, status);
1538 	if (mask) {
1539 		for_each_set_bit(i, &mask, ARRAY_SIZE(xdev->chan))
1540 			xilinx_dpdma_chan_notify_no_ostand(xdev->chan[i]);
1541 	}
1542 
1543 	mask = status & XILINX_DPDMA_INTR_ERR_ALL;
1544 	if (mask || error)
1545 		xilinx_dpdma_handle_err_irq(xdev, mask, error);
1546 
1547 	return IRQ_HANDLED;
1548 }
1549 
1550 /* -----------------------------------------------------------------------------
1551  * Initialization & Cleanup
1552  */
1553 
xilinx_dpdma_chan_init(struct xilinx_dpdma_device * xdev,unsigned int chan_id)1554 static int xilinx_dpdma_chan_init(struct xilinx_dpdma_device *xdev,
1555 				  unsigned int chan_id)
1556 {
1557 	struct xilinx_dpdma_chan *chan;
1558 
1559 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
1560 	if (!chan)
1561 		return -ENOMEM;
1562 
1563 	chan->id = chan_id;
1564 	chan->reg = xdev->reg + XILINX_DPDMA_CH_BASE
1565 		  + XILINX_DPDMA_CH_OFFSET * chan->id;
1566 	chan->running = false;
1567 	chan->xdev = xdev;
1568 
1569 	spin_lock_init(&chan->lock);
1570 	init_waitqueue_head(&chan->wait_to_stop);
1571 
1572 	tasklet_setup(&chan->err_task, xilinx_dpdma_chan_err_task);
1573 
1574 	chan->vchan.desc_free = xilinx_dpdma_chan_free_tx_desc;
1575 	vchan_init(&chan->vchan, &xdev->common);
1576 
1577 	xdev->chan[chan->id] = chan;
1578 
1579 	return 0;
1580 }
1581 
xilinx_dpdma_chan_remove(struct xilinx_dpdma_chan * chan)1582 static void xilinx_dpdma_chan_remove(struct xilinx_dpdma_chan *chan)
1583 {
1584 	if (!chan)
1585 		return;
1586 
1587 	tasklet_kill(&chan->err_task);
1588 	list_del(&chan->vchan.chan.device_node);
1589 }
1590 
of_dma_xilinx_xlate(struct of_phandle_args * dma_spec,struct of_dma * ofdma)1591 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
1592 					    struct of_dma *ofdma)
1593 {
1594 	struct xilinx_dpdma_device *xdev = ofdma->of_dma_data;
1595 	u32 chan_id = dma_spec->args[0];
1596 
1597 	if (chan_id >= ARRAY_SIZE(xdev->chan))
1598 		return NULL;
1599 
1600 	if (!xdev->chan[chan_id])
1601 		return NULL;
1602 
1603 	return dma_get_slave_channel(&xdev->chan[chan_id]->vchan.chan);
1604 }
1605 
dpdma_hw_init(struct xilinx_dpdma_device * xdev)1606 static void dpdma_hw_init(struct xilinx_dpdma_device *xdev)
1607 {
1608 	unsigned int i;
1609 	void __iomem *reg;
1610 
1611 	/* Disable all interrupts */
1612 	xilinx_dpdma_disable_irq(xdev);
1613 
1614 	/* Stop all channels */
1615 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++) {
1616 		reg = xdev->reg + XILINX_DPDMA_CH_BASE
1617 				+ XILINX_DPDMA_CH_OFFSET * i;
1618 		dpdma_clr(reg, XILINX_DPDMA_CH_CNTL, XILINX_DPDMA_CH_CNTL_ENABLE);
1619 	}
1620 
1621 	/* Clear the interrupt status registers */
1622 	dpdma_write(xdev->reg, XILINX_DPDMA_ISR, XILINX_DPDMA_INTR_ALL);
1623 	dpdma_write(xdev->reg, XILINX_DPDMA_EISR, XILINX_DPDMA_EINTR_ALL);
1624 }
1625 
xilinx_dpdma_probe(struct platform_device * pdev)1626 static int xilinx_dpdma_probe(struct platform_device *pdev)
1627 {
1628 	struct xilinx_dpdma_device *xdev;
1629 	struct dma_device *ddev;
1630 	unsigned int i;
1631 	int ret;
1632 
1633 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
1634 	if (!xdev)
1635 		return -ENOMEM;
1636 
1637 	xdev->dev = &pdev->dev;
1638 	xdev->ext_addr = sizeof(dma_addr_t) > 4;
1639 
1640 	INIT_LIST_HEAD(&xdev->common.channels);
1641 
1642 	platform_set_drvdata(pdev, xdev);
1643 
1644 	xdev->axi_clk = devm_clk_get(xdev->dev, "axi_clk");
1645 	if (IS_ERR(xdev->axi_clk))
1646 		return PTR_ERR(xdev->axi_clk);
1647 
1648 	xdev->reg = devm_platform_ioremap_resource(pdev, 0);
1649 	if (IS_ERR(xdev->reg))
1650 		return PTR_ERR(xdev->reg);
1651 
1652 	dpdma_hw_init(xdev);
1653 
1654 	xdev->irq = platform_get_irq(pdev, 0);
1655 	if (xdev->irq < 0) {
1656 		dev_err(xdev->dev, "failed to get platform irq\n");
1657 		return xdev->irq;
1658 	}
1659 
1660 	ret = request_irq(xdev->irq, xilinx_dpdma_irq_handler, IRQF_SHARED,
1661 			  dev_name(xdev->dev), xdev);
1662 	if (ret) {
1663 		dev_err(xdev->dev, "failed to request IRQ\n");
1664 		return ret;
1665 	}
1666 
1667 	ddev = &xdev->common;
1668 	ddev->dev = &pdev->dev;
1669 
1670 	dma_cap_set(DMA_SLAVE, ddev->cap_mask);
1671 	dma_cap_set(DMA_PRIVATE, ddev->cap_mask);
1672 	dma_cap_set(DMA_INTERLEAVE, ddev->cap_mask);
1673 	dma_cap_set(DMA_REPEAT, ddev->cap_mask);
1674 	dma_cap_set(DMA_LOAD_EOT, ddev->cap_mask);
1675 	ddev->copy_align = fls(XILINX_DPDMA_ALIGN_BYTES - 1);
1676 
1677 	ddev->device_alloc_chan_resources = xilinx_dpdma_alloc_chan_resources;
1678 	ddev->device_free_chan_resources = xilinx_dpdma_free_chan_resources;
1679 	ddev->device_prep_interleaved_dma = xilinx_dpdma_prep_interleaved_dma;
1680 	/* TODO: Can we achieve better granularity ? */
1681 	ddev->device_tx_status = dma_cookie_status;
1682 	ddev->device_issue_pending = xilinx_dpdma_issue_pending;
1683 	ddev->device_config = xilinx_dpdma_config;
1684 	ddev->device_pause = xilinx_dpdma_pause;
1685 	ddev->device_resume = xilinx_dpdma_resume;
1686 	ddev->device_terminate_all = xilinx_dpdma_terminate_all;
1687 	ddev->device_synchronize = xilinx_dpdma_synchronize;
1688 	ddev->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED);
1689 	ddev->directions = BIT(DMA_MEM_TO_DEV);
1690 	ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1691 
1692 	for (i = 0; i < ARRAY_SIZE(xdev->chan); ++i) {
1693 		ret = xilinx_dpdma_chan_init(xdev, i);
1694 		if (ret < 0) {
1695 			dev_err(xdev->dev, "failed to initialize channel %u\n",
1696 				i);
1697 			goto error;
1698 		}
1699 	}
1700 
1701 	ret = clk_prepare_enable(xdev->axi_clk);
1702 	if (ret) {
1703 		dev_err(xdev->dev, "failed to enable the axi clock\n");
1704 		goto error;
1705 	}
1706 
1707 	ret = dma_async_device_register(ddev);
1708 	if (ret) {
1709 		dev_err(xdev->dev, "failed to register the dma device\n");
1710 		goto error_dma_async;
1711 	}
1712 
1713 	ret = of_dma_controller_register(xdev->dev->of_node,
1714 					 of_dma_xilinx_xlate, ddev);
1715 	if (ret) {
1716 		dev_err(xdev->dev, "failed to register DMA to DT DMA helper\n");
1717 		goto error_of_dma;
1718 	}
1719 
1720 	xilinx_dpdma_enable_irq(xdev);
1721 
1722 	xilinx_dpdma_debugfs_init(xdev);
1723 
1724 	dev_info(&pdev->dev, "Xilinx DPDMA engine is probed\n");
1725 
1726 	return 0;
1727 
1728 error_of_dma:
1729 	dma_async_device_unregister(ddev);
1730 error_dma_async:
1731 	clk_disable_unprepare(xdev->axi_clk);
1732 error:
1733 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1734 		xilinx_dpdma_chan_remove(xdev->chan[i]);
1735 
1736 	free_irq(xdev->irq, xdev);
1737 
1738 	return ret;
1739 }
1740 
xilinx_dpdma_remove(struct platform_device * pdev)1741 static int xilinx_dpdma_remove(struct platform_device *pdev)
1742 {
1743 	struct xilinx_dpdma_device *xdev = platform_get_drvdata(pdev);
1744 	unsigned int i;
1745 
1746 	/* Start by disabling the IRQ to avoid races during cleanup. */
1747 	free_irq(xdev->irq, xdev);
1748 
1749 	xilinx_dpdma_disable_irq(xdev);
1750 	of_dma_controller_free(pdev->dev.of_node);
1751 	dma_async_device_unregister(&xdev->common);
1752 	clk_disable_unprepare(xdev->axi_clk);
1753 
1754 	for (i = 0; i < ARRAY_SIZE(xdev->chan); i++)
1755 		xilinx_dpdma_chan_remove(xdev->chan[i]);
1756 
1757 	return 0;
1758 }
1759 
1760 static const struct of_device_id xilinx_dpdma_of_match[] = {
1761 	{ .compatible = "xlnx,zynqmp-dpdma",},
1762 	{ /* end of table */ },
1763 };
1764 MODULE_DEVICE_TABLE(of, xilinx_dpdma_of_match);
1765 
1766 static struct platform_driver xilinx_dpdma_driver = {
1767 	.probe			= xilinx_dpdma_probe,
1768 	.remove			= xilinx_dpdma_remove,
1769 	.driver			= {
1770 		.name		= "xilinx-zynqmp-dpdma",
1771 		.of_match_table	= xilinx_dpdma_of_match,
1772 	},
1773 };
1774 
1775 module_platform_driver(xilinx_dpdma_driver);
1776 
1777 MODULE_AUTHOR("Xilinx, Inc.");
1778 MODULE_DESCRIPTION("Xilinx ZynqMP DPDMA driver");
1779 MODULE_LICENSE("GPL v2");
1780