1/*
2 * DMA driver for Xilinx Video DMA Engine
3 *
4 * Copyright (C) 2010-2014 Xilinx, Inc. All rights reserved.
5 *
6 * Based on the Freescale DMA driver.
7 *
8 * Description:
9 * The AXI Video Direct Memory Access (AXI VDMA) core is a soft Xilinx IP
10 * core that provides high-bandwidth direct memory access between memory
11 * and AXI4-Stream type video target peripherals. The core provides efficient
12 * two dimensional DMA operations with independent asynchronous read (S2MM)
13 * and write (MM2S) channel operation. It can be configured to have either
14 * one channel or two channels. If configured as two channels, one is to
15 * transmit to the video device (MM2S) and another is to receive from the
16 * video device (S2MM). Initialization, status, interrupt and management
17 * registers are accessed through an AXI4-Lite slave interface.
18 *
19 * This program is free software: you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation, either version 2 of the License, or
22 * (at your option) any later version.
23 */
24
25#include <linux/bitops.h>
26#include <linux/dmapool.h>
27#include <linux/dma/xilinx_dma.h>
28#include <linux/init.h>
29#include <linux/interrupt.h>
30#include <linux/io.h>
31#include <linux/module.h>
32#include <linux/of_address.h>
33#include <linux/of_dma.h>
34#include <linux/of_platform.h>
35#include <linux/of_irq.h>
36#include <linux/slab.h>
37
38#include "../dmaengine.h"
39
40/* Register/Descriptor Offsets */
41#define XILINX_VDMA_MM2S_CTRL_OFFSET		0x0000
42#define XILINX_VDMA_S2MM_CTRL_OFFSET		0x0030
43#define XILINX_VDMA_MM2S_DESC_OFFSET		0x0050
44#define XILINX_VDMA_S2MM_DESC_OFFSET		0x00a0
45
46/* Control Registers */
47#define XILINX_VDMA_REG_DMACR			0x0000
48#define XILINX_VDMA_DMACR_DELAY_MAX		0xff
49#define XILINX_VDMA_DMACR_DELAY_SHIFT		24
50#define XILINX_VDMA_DMACR_FRAME_COUNT_MAX	0xff
51#define XILINX_VDMA_DMACR_FRAME_COUNT_SHIFT	16
52#define XILINX_VDMA_DMACR_ERR_IRQ		BIT(14)
53#define XILINX_VDMA_DMACR_DLY_CNT_IRQ		BIT(13)
54#define XILINX_VDMA_DMACR_FRM_CNT_IRQ		BIT(12)
55#define XILINX_VDMA_DMACR_MASTER_SHIFT		8
56#define XILINX_VDMA_DMACR_FSYNCSRC_SHIFT	5
57#define XILINX_VDMA_DMACR_FRAMECNT_EN		BIT(4)
58#define XILINX_VDMA_DMACR_GENLOCK_EN		BIT(3)
59#define XILINX_VDMA_DMACR_RESET			BIT(2)
60#define XILINX_VDMA_DMACR_CIRC_EN		BIT(1)
61#define XILINX_VDMA_DMACR_RUNSTOP		BIT(0)
62#define XILINX_VDMA_DMACR_FSYNCSRC_MASK		GENMASK(6, 5)
63
64#define XILINX_VDMA_REG_DMASR			0x0004
65#define XILINX_VDMA_DMASR_EOL_LATE_ERR		BIT(15)
66#define XILINX_VDMA_DMASR_ERR_IRQ		BIT(14)
67#define XILINX_VDMA_DMASR_DLY_CNT_IRQ		BIT(13)
68#define XILINX_VDMA_DMASR_FRM_CNT_IRQ		BIT(12)
69#define XILINX_VDMA_DMASR_SOF_LATE_ERR		BIT(11)
70#define XILINX_VDMA_DMASR_SG_DEC_ERR		BIT(10)
71#define XILINX_VDMA_DMASR_SG_SLV_ERR		BIT(9)
72#define XILINX_VDMA_DMASR_EOF_EARLY_ERR		BIT(8)
73#define XILINX_VDMA_DMASR_SOF_EARLY_ERR		BIT(7)
74#define XILINX_VDMA_DMASR_DMA_DEC_ERR		BIT(6)
75#define XILINX_VDMA_DMASR_DMA_SLAVE_ERR		BIT(5)
76#define XILINX_VDMA_DMASR_DMA_INT_ERR		BIT(4)
77#define XILINX_VDMA_DMASR_IDLE			BIT(1)
78#define XILINX_VDMA_DMASR_HALTED		BIT(0)
79#define XILINX_VDMA_DMASR_DELAY_MASK		GENMASK(31, 24)
80#define XILINX_VDMA_DMASR_FRAME_COUNT_MASK	GENMASK(23, 16)
81
82#define XILINX_VDMA_REG_CURDESC			0x0008
83#define XILINX_VDMA_REG_TAILDESC		0x0010
84#define XILINX_VDMA_REG_REG_INDEX		0x0014
85#define XILINX_VDMA_REG_FRMSTORE		0x0018
86#define XILINX_VDMA_REG_THRESHOLD		0x001c
87#define XILINX_VDMA_REG_FRMPTR_STS		0x0024
88#define XILINX_VDMA_REG_PARK_PTR		0x0028
89#define XILINX_VDMA_PARK_PTR_WR_REF_SHIFT	8
90#define XILINX_VDMA_PARK_PTR_RD_REF_SHIFT	0
91#define XILINX_VDMA_REG_VDMA_VERSION		0x002c
92
93/* Register Direct Mode Registers */
94#define XILINX_VDMA_REG_VSIZE			0x0000
95#define XILINX_VDMA_REG_HSIZE			0x0004
96
97#define XILINX_VDMA_REG_FRMDLY_STRIDE		0x0008
98#define XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_SHIFT	24
99#define XILINX_VDMA_FRMDLY_STRIDE_STRIDE_SHIFT	0
100
101#define XILINX_VDMA_REG_START_ADDRESS(n)	(0x000c + 4 * (n))
102
103/* HW specific definitions */
104#define XILINX_VDMA_MAX_CHANS_PER_DEVICE	0x2
105
106#define XILINX_VDMA_DMAXR_ALL_IRQ_MASK	\
107		(XILINX_VDMA_DMASR_FRM_CNT_IRQ | \
108		 XILINX_VDMA_DMASR_DLY_CNT_IRQ | \
109		 XILINX_VDMA_DMASR_ERR_IRQ)
110
111#define XILINX_VDMA_DMASR_ALL_ERR_MASK	\
112		(XILINX_VDMA_DMASR_EOL_LATE_ERR | \
113		 XILINX_VDMA_DMASR_SOF_LATE_ERR | \
114		 XILINX_VDMA_DMASR_SG_DEC_ERR | \
115		 XILINX_VDMA_DMASR_SG_SLV_ERR | \
116		 XILINX_VDMA_DMASR_EOF_EARLY_ERR | \
117		 XILINX_VDMA_DMASR_SOF_EARLY_ERR | \
118		 XILINX_VDMA_DMASR_DMA_DEC_ERR | \
119		 XILINX_VDMA_DMASR_DMA_SLAVE_ERR | \
120		 XILINX_VDMA_DMASR_DMA_INT_ERR)
121
122/*
123 * Recoverable errors are DMA Internal error, SOF Early, EOF Early
124 * and SOF Late. They are only recoverable when C_FLUSH_ON_FSYNC
125 * is enabled in the h/w system.
126 */
127#define XILINX_VDMA_DMASR_ERR_RECOVER_MASK	\
128		(XILINX_VDMA_DMASR_SOF_LATE_ERR | \
129		 XILINX_VDMA_DMASR_EOF_EARLY_ERR | \
130		 XILINX_VDMA_DMASR_SOF_EARLY_ERR | \
131		 XILINX_VDMA_DMASR_DMA_INT_ERR)
132
133/* Axi VDMA Flush on Fsync bits */
134#define XILINX_VDMA_FLUSH_S2MM		3
135#define XILINX_VDMA_FLUSH_MM2S		2
136#define XILINX_VDMA_FLUSH_BOTH		1
137
138/* Delay loop counter to prevent hardware failure */
139#define XILINX_VDMA_LOOP_COUNT		1000000
140
141/**
142 * struct xilinx_vdma_desc_hw - Hardware Descriptor
143 * @next_desc: Next Descriptor Pointer @0x00
144 * @pad1: Reserved @0x04
145 * @buf_addr: Buffer address @0x08
146 * @pad2: Reserved @0x0C
147 * @vsize: Vertical Size @0x10
148 * @hsize: Horizontal Size @0x14
149 * @stride: Number of bytes between the first
150 *	    pixels of each horizontal line @0x18
151 */
152struct xilinx_vdma_desc_hw {
153	u32 next_desc;
154	u32 pad1;
155	u32 buf_addr;
156	u32 pad2;
157	u32 vsize;
158	u32 hsize;
159	u32 stride;
160} __aligned(64);
161
162/**
163 * struct xilinx_vdma_tx_segment - Descriptor segment
164 * @hw: Hardware descriptor
165 * @node: Node in the descriptor segments list
166 * @phys: Physical address of segment
167 */
168struct xilinx_vdma_tx_segment {
169	struct xilinx_vdma_desc_hw hw;
170	struct list_head node;
171	dma_addr_t phys;
172} __aligned(64);
173
174/**
175 * struct xilinx_vdma_tx_descriptor - Per Transaction structure
176 * @async_tx: Async transaction descriptor
177 * @segments: TX segments list
178 * @node: Node in the channel descriptors list
179 */
180struct xilinx_vdma_tx_descriptor {
181	struct dma_async_tx_descriptor async_tx;
182	struct list_head segments;
183	struct list_head node;
184};
185
186/**
187 * struct xilinx_vdma_chan - Driver specific VDMA channel structure
188 * @xdev: Driver specific device structure
189 * @ctrl_offset: Control registers offset
190 * @desc_offset: TX descriptor registers offset
191 * @lock: Descriptor operation lock
192 * @pending_list: Descriptors waiting
193 * @active_desc: Active descriptor
194 * @allocated_desc: Allocated descriptor
195 * @done_list: Complete descriptors
196 * @common: DMA common channel
197 * @desc_pool: Descriptors pool
198 * @dev: The dma device
199 * @irq: Channel IRQ
200 * @id: Channel ID
201 * @direction: Transfer direction
202 * @num_frms: Number of frames
203 * @has_sg: Support scatter transfers
204 * @genlock: Support genlock mode
205 * @err: Channel has errors
206 * @tasklet: Cleanup work after irq
207 * @config: Device configuration info
208 * @flush_on_fsync: Flush on Frame sync
209 */
210struct xilinx_vdma_chan {
211	struct xilinx_vdma_device *xdev;
212	u32 ctrl_offset;
213	u32 desc_offset;
214	spinlock_t lock;
215	struct list_head pending_list;
216	struct xilinx_vdma_tx_descriptor *active_desc;
217	struct xilinx_vdma_tx_descriptor *allocated_desc;
218	struct list_head done_list;
219	struct dma_chan common;
220	struct dma_pool *desc_pool;
221	struct device *dev;
222	int irq;
223	int id;
224	enum dma_transfer_direction direction;
225	int num_frms;
226	bool has_sg;
227	bool genlock;
228	bool err;
229	struct tasklet_struct tasklet;
230	struct xilinx_vdma_config config;
231	bool flush_on_fsync;
232};
233
234/**
235 * struct xilinx_vdma_device - VDMA device structure
236 * @regs: I/O mapped base address
237 * @dev: Device Structure
238 * @common: DMA device structure
239 * @chan: Driver specific VDMA channel
240 * @has_sg: Specifies whether Scatter-Gather is present or not
241 * @flush_on_fsync: Flush on frame sync
242 */
243struct xilinx_vdma_device {
244	void __iomem *regs;
245	struct device *dev;
246	struct dma_device common;
247	struct xilinx_vdma_chan *chan[XILINX_VDMA_MAX_CHANS_PER_DEVICE];
248	bool has_sg;
249	u32 flush_on_fsync;
250};
251
252/* Macros */
253#define to_xilinx_chan(chan) \
254	container_of(chan, struct xilinx_vdma_chan, common)
255#define to_vdma_tx_descriptor(tx) \
256	container_of(tx, struct xilinx_vdma_tx_descriptor, async_tx)
257
258/* IO accessors */
259static inline u32 vdma_read(struct xilinx_vdma_chan *chan, u32 reg)
260{
261	return ioread32(chan->xdev->regs + reg);
262}
263
264static inline void vdma_write(struct xilinx_vdma_chan *chan, u32 reg, u32 value)
265{
266	iowrite32(value, chan->xdev->regs + reg);
267}
268
269static inline void vdma_desc_write(struct xilinx_vdma_chan *chan, u32 reg,
270				   u32 value)
271{
272	vdma_write(chan, chan->desc_offset + reg, value);
273}
274
275static inline u32 vdma_ctrl_read(struct xilinx_vdma_chan *chan, u32 reg)
276{
277	return vdma_read(chan, chan->ctrl_offset + reg);
278}
279
280static inline void vdma_ctrl_write(struct xilinx_vdma_chan *chan, u32 reg,
281				   u32 value)
282{
283	vdma_write(chan, chan->ctrl_offset + reg, value);
284}
285
286static inline void vdma_ctrl_clr(struct xilinx_vdma_chan *chan, u32 reg,
287				 u32 clr)
288{
289	vdma_ctrl_write(chan, reg, vdma_ctrl_read(chan, reg) & ~clr);
290}
291
292static inline void vdma_ctrl_set(struct xilinx_vdma_chan *chan, u32 reg,
293				 u32 set)
294{
295	vdma_ctrl_write(chan, reg, vdma_ctrl_read(chan, reg) | set);
296}
297
298/* -----------------------------------------------------------------------------
299 * Descriptors and segments alloc and free
300 */
301
302/**
303 * xilinx_vdma_alloc_tx_segment - Allocate transaction segment
304 * @chan: Driver specific VDMA channel
305 *
306 * Return: The allocated segment on success and NULL on failure.
307 */
308static struct xilinx_vdma_tx_segment *
309xilinx_vdma_alloc_tx_segment(struct xilinx_vdma_chan *chan)
310{
311	struct xilinx_vdma_tx_segment *segment;
312	dma_addr_t phys;
313
314	segment = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &phys);
315	if (!segment)
316		return NULL;
317
318	memset(segment, 0, sizeof(*segment));
319	segment->phys = phys;
320
321	return segment;
322}
323
324/**
325 * xilinx_vdma_free_tx_segment - Free transaction segment
326 * @chan: Driver specific VDMA channel
327 * @segment: VDMA transaction segment
328 */
329static void xilinx_vdma_free_tx_segment(struct xilinx_vdma_chan *chan,
330					struct xilinx_vdma_tx_segment *segment)
331{
332	dma_pool_free(chan->desc_pool, segment, segment->phys);
333}
334
335/**
336 * xilinx_vdma_tx_descriptor - Allocate transaction descriptor
337 * @chan: Driver specific VDMA channel
338 *
339 * Return: The allocated descriptor on success and NULL on failure.
340 */
341static struct xilinx_vdma_tx_descriptor *
342xilinx_vdma_alloc_tx_descriptor(struct xilinx_vdma_chan *chan)
343{
344	struct xilinx_vdma_tx_descriptor *desc;
345	unsigned long flags;
346
347	if (chan->allocated_desc)
348		return chan->allocated_desc;
349
350	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
351	if (!desc)
352		return NULL;
353
354	spin_lock_irqsave(&chan->lock, flags);
355	chan->allocated_desc = desc;
356	spin_unlock_irqrestore(&chan->lock, flags);
357
358	INIT_LIST_HEAD(&desc->segments);
359
360	return desc;
361}
362
363/**
364 * xilinx_vdma_free_tx_descriptor - Free transaction descriptor
365 * @chan: Driver specific VDMA channel
366 * @desc: VDMA transaction descriptor
367 */
368static void
369xilinx_vdma_free_tx_descriptor(struct xilinx_vdma_chan *chan,
370			       struct xilinx_vdma_tx_descriptor *desc)
371{
372	struct xilinx_vdma_tx_segment *segment, *next;
373
374	if (!desc)
375		return;
376
377	list_for_each_entry_safe(segment, next, &desc->segments, node) {
378		list_del(&segment->node);
379		xilinx_vdma_free_tx_segment(chan, segment);
380	}
381
382	kfree(desc);
383}
384
385/* Required functions */
386
387/**
388 * xilinx_vdma_free_desc_list - Free descriptors list
389 * @chan: Driver specific VDMA channel
390 * @list: List to parse and delete the descriptor
391 */
392static void xilinx_vdma_free_desc_list(struct xilinx_vdma_chan *chan,
393					struct list_head *list)
394{
395	struct xilinx_vdma_tx_descriptor *desc, *next;
396
397	list_for_each_entry_safe(desc, next, list, node) {
398		list_del(&desc->node);
399		xilinx_vdma_free_tx_descriptor(chan, desc);
400	}
401}
402
403/**
404 * xilinx_vdma_free_descriptors - Free channel descriptors
405 * @chan: Driver specific VDMA channel
406 */
407static void xilinx_vdma_free_descriptors(struct xilinx_vdma_chan *chan)
408{
409	unsigned long flags;
410
411	spin_lock_irqsave(&chan->lock, flags);
412
413	xilinx_vdma_free_desc_list(chan, &chan->pending_list);
414	xilinx_vdma_free_desc_list(chan, &chan->done_list);
415
416	xilinx_vdma_free_tx_descriptor(chan, chan->active_desc);
417	chan->active_desc = NULL;
418
419	spin_unlock_irqrestore(&chan->lock, flags);
420}
421
422/**
423 * xilinx_vdma_free_chan_resources - Free channel resources
424 * @dchan: DMA channel
425 */
426static void xilinx_vdma_free_chan_resources(struct dma_chan *dchan)
427{
428	struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan);
429
430	dev_dbg(chan->dev, "Free all channel resources.\n");
431
432	xilinx_vdma_free_descriptors(chan);
433	dma_pool_destroy(chan->desc_pool);
434	chan->desc_pool = NULL;
435}
436
437/**
438 * xilinx_vdma_chan_desc_cleanup - Clean channel descriptors
439 * @chan: Driver specific VDMA channel
440 */
441static void xilinx_vdma_chan_desc_cleanup(struct xilinx_vdma_chan *chan)
442{
443	struct xilinx_vdma_tx_descriptor *desc, *next;
444	unsigned long flags;
445
446	spin_lock_irqsave(&chan->lock, flags);
447
448	list_for_each_entry_safe(desc, next, &chan->done_list, node) {
449		dma_async_tx_callback callback;
450		void *callback_param;
451
452		/* Remove from the list of running transactions */
453		list_del(&desc->node);
454
455		/* Run the link descriptor callback function */
456		callback = desc->async_tx.callback;
457		callback_param = desc->async_tx.callback_param;
458		if (callback) {
459			spin_unlock_irqrestore(&chan->lock, flags);
460			callback(callback_param);
461			spin_lock_irqsave(&chan->lock, flags);
462		}
463
464		/* Run any dependencies, then free the descriptor */
465		dma_run_dependencies(&desc->async_tx);
466		xilinx_vdma_free_tx_descriptor(chan, desc);
467	}
468
469	spin_unlock_irqrestore(&chan->lock, flags);
470}
471
472/**
473 * xilinx_vdma_do_tasklet - Schedule completion tasklet
474 * @data: Pointer to the Xilinx VDMA channel structure
475 */
476static void xilinx_vdma_do_tasklet(unsigned long data)
477{
478	struct xilinx_vdma_chan *chan = (struct xilinx_vdma_chan *)data;
479
480	xilinx_vdma_chan_desc_cleanup(chan);
481}
482
483/**
484 * xilinx_vdma_alloc_chan_resources - Allocate channel resources
485 * @dchan: DMA channel
486 *
487 * Return: '0' on success and failure value on error
488 */
489static int xilinx_vdma_alloc_chan_resources(struct dma_chan *dchan)
490{
491	struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan);
492
493	/* Has this channel already been allocated? */
494	if (chan->desc_pool)
495		return 0;
496
497	/*
498	 * We need the descriptor to be aligned to 64bytes
499	 * for meeting Xilinx VDMA specification requirement.
500	 */
501	chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
502				chan->dev,
503				sizeof(struct xilinx_vdma_tx_segment),
504				__alignof__(struct xilinx_vdma_tx_segment), 0);
505	if (!chan->desc_pool) {
506		dev_err(chan->dev,
507			"unable to allocate channel %d descriptor pool\n",
508			chan->id);
509		return -ENOMEM;
510	}
511
512	dma_cookie_init(dchan);
513	return 0;
514}
515
516/**
517 * xilinx_vdma_tx_status - Get VDMA transaction status
518 * @dchan: DMA channel
519 * @cookie: Transaction identifier
520 * @txstate: Transaction state
521 *
522 * Return: DMA transaction status
523 */
524static enum dma_status xilinx_vdma_tx_status(struct dma_chan *dchan,
525					dma_cookie_t cookie,
526					struct dma_tx_state *txstate)
527{
528	return dma_cookie_status(dchan, cookie, txstate);
529}
530
531/**
532 * xilinx_vdma_is_running - Check if VDMA channel is running
533 * @chan: Driver specific VDMA channel
534 *
535 * Return: '1' if running, '0' if not.
536 */
537static bool xilinx_vdma_is_running(struct xilinx_vdma_chan *chan)
538{
539	return !(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) &
540		 XILINX_VDMA_DMASR_HALTED) &&
541		(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) &
542		 XILINX_VDMA_DMACR_RUNSTOP);
543}
544
545/**
546 * xilinx_vdma_is_idle - Check if VDMA channel is idle
547 * @chan: Driver specific VDMA channel
548 *
549 * Return: '1' if idle, '0' if not.
550 */
551static bool xilinx_vdma_is_idle(struct xilinx_vdma_chan *chan)
552{
553	return vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) &
554		XILINX_VDMA_DMASR_IDLE;
555}
556
557/**
558 * xilinx_vdma_halt - Halt VDMA channel
559 * @chan: Driver specific VDMA channel
560 */
561static void xilinx_vdma_halt(struct xilinx_vdma_chan *chan)
562{
563	int loop = XILINX_VDMA_LOOP_COUNT;
564
565	vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP);
566
567	/* Wait for the hardware to halt */
568	do {
569		if (vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) &
570		    XILINX_VDMA_DMASR_HALTED)
571			break;
572	} while (loop--);
573
574	if (!loop) {
575		dev_err(chan->dev, "Cannot stop channel %p: %x\n",
576			chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR));
577		chan->err = true;
578	}
579
580	return;
581}
582
583/**
584 * xilinx_vdma_start - Start VDMA channel
585 * @chan: Driver specific VDMA channel
586 */
587static void xilinx_vdma_start(struct xilinx_vdma_chan *chan)
588{
589	int loop = XILINX_VDMA_LOOP_COUNT;
590
591	vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP);
592
593	/* Wait for the hardware to start */
594	do {
595		if (!(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) &
596		      XILINX_VDMA_DMASR_HALTED))
597			break;
598	} while (loop--);
599
600	if (!loop) {
601		dev_err(chan->dev, "Cannot start channel %p: %x\n",
602			chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR));
603
604		chan->err = true;
605	}
606
607	return;
608}
609
610/**
611 * xilinx_vdma_start_transfer - Starts VDMA transfer
612 * @chan: Driver specific channel struct pointer
613 */
614static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan)
615{
616	struct xilinx_vdma_config *config = &chan->config;
617	struct xilinx_vdma_tx_descriptor *desc;
618	unsigned long flags;
619	u32 reg;
620	struct xilinx_vdma_tx_segment *head, *tail = NULL;
621
622	if (chan->err)
623		return;
624
625	spin_lock_irqsave(&chan->lock, flags);
626
627	/* There's already an active descriptor, bail out. */
628	if (chan->active_desc)
629		goto out_unlock;
630
631	if (list_empty(&chan->pending_list))
632		goto out_unlock;
633
634	desc = list_first_entry(&chan->pending_list,
635				struct xilinx_vdma_tx_descriptor, node);
636
637	/* If it is SG mode and hardware is busy, cannot submit */
638	if (chan->has_sg && xilinx_vdma_is_running(chan) &&
639	    !xilinx_vdma_is_idle(chan)) {
640		dev_dbg(chan->dev, "DMA controller still busy\n");
641		goto out_unlock;
642	}
643
644	/*
645	 * If hardware is idle, then all descriptors on the running lists are
646	 * done, start new transfers
647	 */
648	if (chan->has_sg) {
649		head = list_first_entry(&desc->segments,
650					struct xilinx_vdma_tx_segment, node);
651		tail = list_entry(desc->segments.prev,
652				  struct xilinx_vdma_tx_segment, node);
653
654		vdma_ctrl_write(chan, XILINX_VDMA_REG_CURDESC, head->phys);
655	}
656
657	/* Configure the hardware using info in the config structure */
658	reg = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR);
659
660	if (config->frm_cnt_en)
661		reg |= XILINX_VDMA_DMACR_FRAMECNT_EN;
662	else
663		reg &= ~XILINX_VDMA_DMACR_FRAMECNT_EN;
664
665	/*
666	 * With SG, start with circular mode, so that BDs can be fetched.
667	 * In direct register mode, if not parking, enable circular mode
668	 */
669	if (chan->has_sg || !config->park)
670		reg |= XILINX_VDMA_DMACR_CIRC_EN;
671
672	if (config->park)
673		reg &= ~XILINX_VDMA_DMACR_CIRC_EN;
674
675	vdma_ctrl_write(chan, XILINX_VDMA_REG_DMACR, reg);
676
677	if (config->park && (config->park_frm >= 0) &&
678			(config->park_frm < chan->num_frms)) {
679		if (chan->direction == DMA_MEM_TO_DEV)
680			vdma_write(chan, XILINX_VDMA_REG_PARK_PTR,
681				config->park_frm <<
682					XILINX_VDMA_PARK_PTR_RD_REF_SHIFT);
683		else
684			vdma_write(chan, XILINX_VDMA_REG_PARK_PTR,
685				config->park_frm <<
686					XILINX_VDMA_PARK_PTR_WR_REF_SHIFT);
687	}
688
689	/* Start the hardware */
690	xilinx_vdma_start(chan);
691
692	if (chan->err)
693		goto out_unlock;
694
695	/* Start the transfer */
696	if (chan->has_sg) {
697		vdma_ctrl_write(chan, XILINX_VDMA_REG_TAILDESC, tail->phys);
698	} else {
699		struct xilinx_vdma_tx_segment *segment, *last = NULL;
700		int i = 0;
701
702		list_for_each_entry(segment, &desc->segments, node) {
703			vdma_desc_write(chan,
704					XILINX_VDMA_REG_START_ADDRESS(i++),
705					segment->hw.buf_addr);
706			last = segment;
707		}
708
709		if (!last)
710			goto out_unlock;
711
712		/* HW expects these parameters to be same for one transaction */
713		vdma_desc_write(chan, XILINX_VDMA_REG_HSIZE, last->hw.hsize);
714		vdma_desc_write(chan, XILINX_VDMA_REG_FRMDLY_STRIDE,
715				last->hw.stride);
716		vdma_desc_write(chan, XILINX_VDMA_REG_VSIZE, last->hw.vsize);
717	}
718
719	list_del(&desc->node);
720	chan->active_desc = desc;
721
722out_unlock:
723	spin_unlock_irqrestore(&chan->lock, flags);
724}
725
726/**
727 * xilinx_vdma_issue_pending - Issue pending transactions
728 * @dchan: DMA channel
729 */
730static void xilinx_vdma_issue_pending(struct dma_chan *dchan)
731{
732	struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan);
733
734	xilinx_vdma_start_transfer(chan);
735}
736
737/**
738 * xilinx_vdma_complete_descriptor - Mark the active descriptor as complete
739 * @chan : xilinx DMA channel
740 *
741 * CONTEXT: hardirq
742 */
743static void xilinx_vdma_complete_descriptor(struct xilinx_vdma_chan *chan)
744{
745	struct xilinx_vdma_tx_descriptor *desc;
746	unsigned long flags;
747
748	spin_lock_irqsave(&chan->lock, flags);
749
750	desc = chan->active_desc;
751	if (!desc) {
752		dev_dbg(chan->dev, "no running descriptors\n");
753		goto out_unlock;
754	}
755
756	dma_cookie_complete(&desc->async_tx);
757	list_add_tail(&desc->node, &chan->done_list);
758
759	chan->active_desc = NULL;
760
761out_unlock:
762	spin_unlock_irqrestore(&chan->lock, flags);
763}
764
765/**
766 * xilinx_vdma_reset - Reset VDMA channel
767 * @chan: Driver specific VDMA channel
768 *
769 * Return: '0' on success and failure value on error
770 */
771static int xilinx_vdma_reset(struct xilinx_vdma_chan *chan)
772{
773	int loop = XILINX_VDMA_LOOP_COUNT;
774	u32 tmp;
775
776	vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RESET);
777
778	tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) &
779		XILINX_VDMA_DMACR_RESET;
780
781	/* Wait for the hardware to finish reset */
782	do {
783		tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) &
784			XILINX_VDMA_DMACR_RESET;
785	} while (loop-- && tmp);
786
787	if (!loop) {
788		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
789			vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR),
790			vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR));
791		return -ETIMEDOUT;
792	}
793
794	chan->err = false;
795
796	return 0;
797}
798
799/**
800 * xilinx_vdma_chan_reset - Reset VDMA channel and enable interrupts
801 * @chan: Driver specific VDMA channel
802 *
803 * Return: '0' on success and failure value on error
804 */
805static int xilinx_vdma_chan_reset(struct xilinx_vdma_chan *chan)
806{
807	int err;
808
809	/* Reset VDMA */
810	err = xilinx_vdma_reset(chan);
811	if (err)
812		return err;
813
814	/* Enable interrupts */
815	vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR,
816		      XILINX_VDMA_DMAXR_ALL_IRQ_MASK);
817
818	return 0;
819}
820
821/**
822 * xilinx_vdma_irq_handler - VDMA Interrupt handler
823 * @irq: IRQ number
824 * @data: Pointer to the Xilinx VDMA channel structure
825 *
826 * Return: IRQ_HANDLED/IRQ_NONE
827 */
828static irqreturn_t xilinx_vdma_irq_handler(int irq, void *data)
829{
830	struct xilinx_vdma_chan *chan = data;
831	u32 status;
832
833	/* Read the status and ack the interrupts. */
834	status = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR);
835	if (!(status & XILINX_VDMA_DMAXR_ALL_IRQ_MASK))
836		return IRQ_NONE;
837
838	vdma_ctrl_write(chan, XILINX_VDMA_REG_DMASR,
839			status & XILINX_VDMA_DMAXR_ALL_IRQ_MASK);
840
841	if (status & XILINX_VDMA_DMASR_ERR_IRQ) {
842		/*
843		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
844		 * error is recoverable, ignore it. Otherwise flag the error.
845		 *
846		 * Only recoverable errors can be cleared in the DMASR register,
847		 * make sure not to write to other error bits to 1.
848		 */
849		u32 errors = status & XILINX_VDMA_DMASR_ALL_ERR_MASK;
850		vdma_ctrl_write(chan, XILINX_VDMA_REG_DMASR,
851				errors & XILINX_VDMA_DMASR_ERR_RECOVER_MASK);
852
853		if (!chan->flush_on_fsync ||
854		    (errors & ~XILINX_VDMA_DMASR_ERR_RECOVER_MASK)) {
855			dev_err(chan->dev,
856				"Channel %p has errors %x, cdr %x tdr %x\n",
857				chan, errors,
858				vdma_ctrl_read(chan, XILINX_VDMA_REG_CURDESC),
859				vdma_ctrl_read(chan, XILINX_VDMA_REG_TAILDESC));
860			chan->err = true;
861		}
862	}
863
864	if (status & XILINX_VDMA_DMASR_DLY_CNT_IRQ) {
865		/*
866		 * Device takes too long to do the transfer when user requires
867		 * responsiveness.
868		 */
869		dev_dbg(chan->dev, "Inter-packet latency too long\n");
870	}
871
872	if (status & XILINX_VDMA_DMASR_FRM_CNT_IRQ) {
873		xilinx_vdma_complete_descriptor(chan);
874		xilinx_vdma_start_transfer(chan);
875	}
876
877	tasklet_schedule(&chan->tasklet);
878	return IRQ_HANDLED;
879}
880
881/**
882 * xilinx_vdma_tx_submit - Submit DMA transaction
883 * @tx: Async transaction descriptor
884 *
885 * Return: cookie value on success and failure value on error
886 */
887static dma_cookie_t xilinx_vdma_tx_submit(struct dma_async_tx_descriptor *tx)
888{
889	struct xilinx_vdma_tx_descriptor *desc = to_vdma_tx_descriptor(tx);
890	struct xilinx_vdma_chan *chan = to_xilinx_chan(tx->chan);
891	dma_cookie_t cookie;
892	unsigned long flags;
893	int err;
894
895	if (chan->err) {
896		/*
897		 * If reset fails, need to hard reset the system.
898		 * Channel is no longer functional
899		 */
900		err = xilinx_vdma_chan_reset(chan);
901		if (err < 0)
902			return err;
903	}
904
905	spin_lock_irqsave(&chan->lock, flags);
906
907	cookie = dma_cookie_assign(tx);
908
909	/* Append the transaction to the pending transactions queue. */
910	list_add_tail(&desc->node, &chan->pending_list);
911
912	/* Free the allocated desc */
913	chan->allocated_desc = NULL;
914
915	spin_unlock_irqrestore(&chan->lock, flags);
916
917	return cookie;
918}
919
920/**
921 * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
922 *	DMA_SLAVE transaction
923 * @dchan: DMA channel
924 * @xt: Interleaved template pointer
925 * @flags: transfer ack flags
926 *
927 * Return: Async transaction descriptor on success and NULL on failure
928 */
929static struct dma_async_tx_descriptor *
930xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
931				 struct dma_interleaved_template *xt,
932				 unsigned long flags)
933{
934	struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan);
935	struct xilinx_vdma_tx_descriptor *desc;
936	struct xilinx_vdma_tx_segment *segment, *prev = NULL;
937	struct xilinx_vdma_desc_hw *hw;
938
939	if (!is_slave_direction(xt->dir))
940		return NULL;
941
942	if (!xt->numf || !xt->sgl[0].size)
943		return NULL;
944
945	if (xt->frame_size != 1)
946		return NULL;
947
948	/* Allocate a transaction descriptor. */
949	desc = xilinx_vdma_alloc_tx_descriptor(chan);
950	if (!desc)
951		return NULL;
952
953	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
954	desc->async_tx.tx_submit = xilinx_vdma_tx_submit;
955	async_tx_ack(&desc->async_tx);
956
957	/* Allocate the link descriptor from DMA pool */
958	segment = xilinx_vdma_alloc_tx_segment(chan);
959	if (!segment)
960		goto error;
961
962	/* Fill in the hardware descriptor */
963	hw = &segment->hw;
964	hw->vsize = xt->numf;
965	hw->hsize = xt->sgl[0].size;
966	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
967			XILINX_VDMA_FRMDLY_STRIDE_STRIDE_SHIFT;
968	hw->stride |= chan->config.frm_dly <<
969			XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
970
971	if (xt->dir != DMA_MEM_TO_DEV)
972		hw->buf_addr = xt->dst_start;
973	else
974		hw->buf_addr = xt->src_start;
975
976	/* Link the previous next descriptor to current */
977	if (!list_empty(&desc->segments)) {
978		prev = list_last_entry(&desc->segments,
979				       struct xilinx_vdma_tx_segment, node);
980		prev->hw.next_desc = segment->phys;
981	}
982
983	/* Insert the segment into the descriptor segments list. */
984	list_add_tail(&segment->node, &desc->segments);
985
986	prev = segment;
987
988	/* Link the last hardware descriptor with the first. */
989	segment = list_first_entry(&desc->segments,
990				   struct xilinx_vdma_tx_segment, node);
991	prev->hw.next_desc = segment->phys;
992
993	return &desc->async_tx;
994
995error:
996	xilinx_vdma_free_tx_descriptor(chan, desc);
997	return NULL;
998}
999
1000/**
1001 * xilinx_vdma_terminate_all - Halt the channel and free descriptors
1002 * @chan: Driver specific VDMA Channel pointer
1003 */
1004static int xilinx_vdma_terminate_all(struct dma_chan *dchan)
1005{
1006	struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan);
1007
1008	/* Halt the DMA engine */
1009	xilinx_vdma_halt(chan);
1010
1011	/* Remove and free all of the descriptors in the lists */
1012	xilinx_vdma_free_descriptors(chan);
1013
1014	return 0;
1015}
1016
1017/**
1018 * xilinx_vdma_channel_set_config - Configure VDMA channel
1019 * Run-time configuration for Axi VDMA, supports:
1020 * . halt the channel
1021 * . configure interrupt coalescing and inter-packet delay threshold
1022 * . start/stop parking
1023 * . enable genlock
1024 *
1025 * @dchan: DMA channel
1026 * @cfg: VDMA device configuration pointer
1027 *
1028 * Return: '0' on success and failure value on error
1029 */
1030int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
1031					struct xilinx_vdma_config *cfg)
1032{
1033	struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan);
1034	u32 dmacr;
1035
1036	if (cfg->reset)
1037		return xilinx_vdma_chan_reset(chan);
1038
1039	dmacr = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR);
1040
1041	chan->config.frm_dly = cfg->frm_dly;
1042	chan->config.park = cfg->park;
1043
1044	/* genlock settings */
1045	chan->config.gen_lock = cfg->gen_lock;
1046	chan->config.master = cfg->master;
1047
1048	if (cfg->gen_lock && chan->genlock) {
1049		dmacr |= XILINX_VDMA_DMACR_GENLOCK_EN;
1050		dmacr |= cfg->master << XILINX_VDMA_DMACR_MASTER_SHIFT;
1051	}
1052
1053	chan->config.frm_cnt_en = cfg->frm_cnt_en;
1054	if (cfg->park)
1055		chan->config.park_frm = cfg->park_frm;
1056	else
1057		chan->config.park_frm = -1;
1058
1059	chan->config.coalesc = cfg->coalesc;
1060	chan->config.delay = cfg->delay;
1061
1062	if (cfg->coalesc <= XILINX_VDMA_DMACR_FRAME_COUNT_MAX) {
1063		dmacr |= cfg->coalesc << XILINX_VDMA_DMACR_FRAME_COUNT_SHIFT;
1064		chan->config.coalesc = cfg->coalesc;
1065	}
1066
1067	if (cfg->delay <= XILINX_VDMA_DMACR_DELAY_MAX) {
1068		dmacr |= cfg->delay << XILINX_VDMA_DMACR_DELAY_SHIFT;
1069		chan->config.delay = cfg->delay;
1070	}
1071
1072	/* FSync Source selection */
1073	dmacr &= ~XILINX_VDMA_DMACR_FSYNCSRC_MASK;
1074	dmacr |= cfg->ext_fsync << XILINX_VDMA_DMACR_FSYNCSRC_SHIFT;
1075
1076	vdma_ctrl_write(chan, XILINX_VDMA_REG_DMACR, dmacr);
1077
1078	return 0;
1079}
1080EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
1081
1082/* -----------------------------------------------------------------------------
1083 * Probe and remove
1084 */
1085
1086/**
1087 * xilinx_vdma_chan_remove - Per Channel remove function
1088 * @chan: Driver specific VDMA channel
1089 */
1090static void xilinx_vdma_chan_remove(struct xilinx_vdma_chan *chan)
1091{
1092	/* Disable all interrupts */
1093	vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR,
1094		      XILINX_VDMA_DMAXR_ALL_IRQ_MASK);
1095
1096	if (chan->irq > 0)
1097		free_irq(chan->irq, chan);
1098
1099	tasklet_kill(&chan->tasklet);
1100
1101	list_del(&chan->common.device_node);
1102}
1103
1104/**
1105 * xilinx_vdma_chan_probe - Per Channel Probing
1106 * It get channel features from the device tree entry and
1107 * initialize special channel handling routines
1108 *
1109 * @xdev: Driver specific device structure
1110 * @node: Device node
1111 *
1112 * Return: '0' on success and failure value on error
1113 */
1114static int xilinx_vdma_chan_probe(struct xilinx_vdma_device *xdev,
1115				  struct device_node *node)
1116{
1117	struct xilinx_vdma_chan *chan;
1118	bool has_dre = false;
1119	u32 value, width;
1120	int err;
1121
1122	/* Allocate and initialize the channel structure */
1123	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
1124	if (!chan)
1125		return -ENOMEM;
1126
1127	chan->dev = xdev->dev;
1128	chan->xdev = xdev;
1129	chan->has_sg = xdev->has_sg;
1130
1131	spin_lock_init(&chan->lock);
1132	INIT_LIST_HEAD(&chan->pending_list);
1133	INIT_LIST_HEAD(&chan->done_list);
1134
1135	/* Retrieve the channel properties from the device tree */
1136	has_dre = of_property_read_bool(node, "xlnx,include-dre");
1137
1138	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
1139
1140	err = of_property_read_u32(node, "xlnx,datawidth", &value);
1141	if (err) {
1142		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
1143		return err;
1144	}
1145	width = value >> 3; /* Convert bits to bytes */
1146
1147	/* If data width is greater than 8 bytes, DRE is not in hw */
1148	if (width > 8)
1149		has_dre = false;
1150
1151	if (!has_dre)
1152		xdev->common.copy_align = fls(width - 1);
1153
1154	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel")) {
1155		chan->direction = DMA_MEM_TO_DEV;
1156		chan->id = 0;
1157
1158		chan->ctrl_offset = XILINX_VDMA_MM2S_CTRL_OFFSET;
1159		chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
1160
1161		if (xdev->flush_on_fsync == XILINX_VDMA_FLUSH_BOTH ||
1162		    xdev->flush_on_fsync == XILINX_VDMA_FLUSH_MM2S)
1163			chan->flush_on_fsync = true;
1164	} else if (of_device_is_compatible(node,
1165					    "xlnx,axi-vdma-s2mm-channel")) {
1166		chan->direction = DMA_DEV_TO_MEM;
1167		chan->id = 1;
1168
1169		chan->ctrl_offset = XILINX_VDMA_S2MM_CTRL_OFFSET;
1170		chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
1171
1172		if (xdev->flush_on_fsync == XILINX_VDMA_FLUSH_BOTH ||
1173		    xdev->flush_on_fsync == XILINX_VDMA_FLUSH_S2MM)
1174			chan->flush_on_fsync = true;
1175	} else {
1176		dev_err(xdev->dev, "Invalid channel compatible node\n");
1177		return -EINVAL;
1178	}
1179
1180	/* Request the interrupt */
1181	chan->irq = irq_of_parse_and_map(node, 0);
1182	err = request_irq(chan->irq, xilinx_vdma_irq_handler, IRQF_SHARED,
1183			  "xilinx-vdma-controller", chan);
1184	if (err) {
1185		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
1186		return err;
1187	}
1188
1189	/* Initialize the tasklet */
1190	tasklet_init(&chan->tasklet, xilinx_vdma_do_tasklet,
1191			(unsigned long)chan);
1192
1193	/*
1194	 * Initialize the DMA channel and add it to the DMA engine channels
1195	 * list.
1196	 */
1197	chan->common.device = &xdev->common;
1198
1199	list_add_tail(&chan->common.device_node, &xdev->common.channels);
1200	xdev->chan[chan->id] = chan;
1201
1202	/* Reset the channel */
1203	err = xilinx_vdma_chan_reset(chan);
1204	if (err < 0) {
1205		dev_err(xdev->dev, "Reset channel failed\n");
1206		return err;
1207	}
1208
1209	return 0;
1210}
1211
1212/**
1213 * of_dma_xilinx_xlate - Translation function
1214 * @dma_spec: Pointer to DMA specifier as found in the device tree
1215 * @ofdma: Pointer to DMA controller data
1216 *
1217 * Return: DMA channel pointer on success and NULL on error
1218 */
1219static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
1220						struct of_dma *ofdma)
1221{
1222	struct xilinx_vdma_device *xdev = ofdma->of_dma_data;
1223	int chan_id = dma_spec->args[0];
1224
1225	if (chan_id >= XILINX_VDMA_MAX_CHANS_PER_DEVICE)
1226		return NULL;
1227
1228	return dma_get_slave_channel(&xdev->chan[chan_id]->common);
1229}
1230
1231/**
1232 * xilinx_vdma_probe - Driver probe function
1233 * @pdev: Pointer to the platform_device structure
1234 *
1235 * Return: '0' on success and failure value on error
1236 */
1237static int xilinx_vdma_probe(struct platform_device *pdev)
1238{
1239	struct device_node *node = pdev->dev.of_node;
1240	struct xilinx_vdma_device *xdev;
1241	struct device_node *child;
1242	struct resource *io;
1243	u32 num_frames;
1244	int i, err;
1245
1246	/* Allocate and initialize the DMA engine structure */
1247	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
1248	if (!xdev)
1249		return -ENOMEM;
1250
1251	xdev->dev = &pdev->dev;
1252
1253	/* Request and map I/O memory */
1254	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1255	xdev->regs = devm_ioremap_resource(&pdev->dev, io);
1256	if (IS_ERR(xdev->regs))
1257		return PTR_ERR(xdev->regs);
1258
1259	/* Retrieve the DMA engine properties from the device tree */
1260	xdev->has_sg = of_property_read_bool(node, "xlnx,include-sg");
1261
1262	err = of_property_read_u32(node, "xlnx,num-fstores", &num_frames);
1263	if (err < 0) {
1264		dev_err(xdev->dev, "missing xlnx,num-fstores property\n");
1265		return err;
1266	}
1267
1268	err = of_property_read_u32(node, "xlnx,flush-fsync",
1269					&xdev->flush_on_fsync);
1270	if (err < 0)
1271		dev_warn(xdev->dev, "missing xlnx,flush-fsync property\n");
1272
1273	/* Initialize the DMA engine */
1274	xdev->common.dev = &pdev->dev;
1275
1276	INIT_LIST_HEAD(&xdev->common.channels);
1277	dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
1278	dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
1279
1280	xdev->common.device_alloc_chan_resources =
1281				xilinx_vdma_alloc_chan_resources;
1282	xdev->common.device_free_chan_resources =
1283				xilinx_vdma_free_chan_resources;
1284	xdev->common.device_prep_interleaved_dma =
1285				xilinx_vdma_dma_prep_interleaved;
1286	xdev->common.device_terminate_all = xilinx_vdma_terminate_all;
1287	xdev->common.device_tx_status = xilinx_vdma_tx_status;
1288	xdev->common.device_issue_pending = xilinx_vdma_issue_pending;
1289
1290	platform_set_drvdata(pdev, xdev);
1291
1292	/* Initialize the channels */
1293	for_each_child_of_node(node, child) {
1294		err = xilinx_vdma_chan_probe(xdev, child);
1295		if (err < 0)
1296			goto error;
1297	}
1298
1299	for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++)
1300		if (xdev->chan[i])
1301			xdev->chan[i]->num_frms = num_frames;
1302
1303	/* Register the DMA engine with the core */
1304	dma_async_device_register(&xdev->common);
1305
1306	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
1307					 xdev);
1308	if (err < 0) {
1309		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
1310		dma_async_device_unregister(&xdev->common);
1311		goto error;
1312	}
1313
1314	dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
1315
1316	return 0;
1317
1318error:
1319	for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++)
1320		if (xdev->chan[i])
1321			xilinx_vdma_chan_remove(xdev->chan[i]);
1322
1323	return err;
1324}
1325
1326/**
1327 * xilinx_vdma_remove - Driver remove function
1328 * @pdev: Pointer to the platform_device structure
1329 *
1330 * Return: Always '0'
1331 */
1332static int xilinx_vdma_remove(struct platform_device *pdev)
1333{
1334	struct xilinx_vdma_device *xdev = platform_get_drvdata(pdev);
1335	int i;
1336
1337	of_dma_controller_free(pdev->dev.of_node);
1338
1339	dma_async_device_unregister(&xdev->common);
1340
1341	for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++)
1342		if (xdev->chan[i])
1343			xilinx_vdma_chan_remove(xdev->chan[i]);
1344
1345	return 0;
1346}
1347
1348static const struct of_device_id xilinx_vdma_of_ids[] = {
1349	{ .compatible = "xlnx,axi-vdma-1.00.a",},
1350	{}
1351};
1352
1353static struct platform_driver xilinx_vdma_driver = {
1354	.driver = {
1355		.name = "xilinx-vdma",
1356		.of_match_table = xilinx_vdma_of_ids,
1357	},
1358	.probe = xilinx_vdma_probe,
1359	.remove = xilinx_vdma_remove,
1360};
1361
1362module_platform_driver(xilinx_vdma_driver);
1363
1364MODULE_AUTHOR("Xilinx, Inc.");
1365MODULE_DESCRIPTION("Xilinx VDMA driver");
1366MODULE_LICENSE("GPL v2");
1367