xref: /linux/drivers/dma/xilinx/xilinx_dma.c (revision 2573c25e2c482b53b6e1142ff3cd28f6de13e659)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * DMA driver for Xilinx Video DMA Engine
4  *
5  * Copyright (C) 2010-2014 Xilinx, Inc. All rights reserved.
6  *
7  * Based on the Freescale DMA driver.
8  *
9  * Description:
10  * The AXI Video Direct Memory Access (AXI VDMA) core is a soft Xilinx IP
11  * core that provides high-bandwidth direct memory access between memory
12  * and AXI4-Stream type video target peripherals. The core provides efficient
13  * two dimensional DMA operations with independent asynchronous read (S2MM)
14  * and write (MM2S) channel operation. It can be configured to have either
15  * one channel or two channels. If configured as two channels, one is to
16  * transmit to the video device (MM2S) and another is to receive from the
17  * video device (S2MM). Initialization, status, interrupt and management
18  * registers are accessed through an AXI4-Lite slave interface.
19  *
20  * The AXI Direct Memory Access (AXI DMA) core is a soft Xilinx IP core that
21  * provides high-bandwidth one dimensional direct memory access between memory
22  * and AXI4-Stream target peripherals. It supports one receive and one
23  * transmit channel, both of them optional at synthesis time.
24  *
25  * The AXI CDMA, is a soft IP, which provides high-bandwidth Direct Memory
26  * Access (DMA) between a memory-mapped source address and a memory-mapped
27  * destination address.
28  *
29  * The AXI Multichannel Direct Memory Access (AXI MCDMA) core is a soft
30  * Xilinx IP that provides high-bandwidth direct memory access between
31  * memory and AXI4-Stream target peripherals. It provides scatter gather
32  * (SG) interface with multiple channels independent configuration support.
33  *
34  */
35 
36 #include <linux/bitops.h>
37 #include <linux/dmapool.h>
38 #include <linux/dma/xilinx_dma.h>
39 #include <linux/init.h>
40 #include <linux/interrupt.h>
41 #include <linux/io.h>
42 #include <linux/iopoll.h>
43 #include <linux/module.h>
44 #include <linux/of.h>
45 #include <linux/of_dma.h>
46 #include <linux/of_irq.h>
47 #include <linux/platform_device.h>
48 #include <linux/slab.h>
49 #include <linux/clk.h>
50 #include <linux/io-64-nonatomic-lo-hi.h>
51 
52 #include "../dmaengine.h"
53 
54 /* Register/Descriptor Offsets */
55 #define XILINX_DMA_MM2S_CTRL_OFFSET		0x0000
56 #define XILINX_DMA_S2MM_CTRL_OFFSET		0x0030
57 #define XILINX_VDMA_MM2S_DESC_OFFSET		0x0050
58 #define XILINX_VDMA_S2MM_DESC_OFFSET		0x00a0
59 
60 /* Control Registers */
61 #define XILINX_DMA_REG_DMACR			0x0000
62 #define XILINX_DMA_DMACR_DELAY_MAX		0xff
63 #define XILINX_DMA_DMACR_DELAY_SHIFT		24
64 #define XILINX_DMA_DMACR_FRAME_COUNT_MAX	0xff
65 #define XILINX_DMA_DMACR_FRAME_COUNT_SHIFT	16
66 #define XILINX_DMA_DMACR_ERR_IRQ		BIT(14)
67 #define XILINX_DMA_DMACR_DLY_CNT_IRQ		BIT(13)
68 #define XILINX_DMA_DMACR_FRM_CNT_IRQ		BIT(12)
69 #define XILINX_DMA_DMACR_MASTER_SHIFT		8
70 #define XILINX_DMA_DMACR_FSYNCSRC_SHIFT	5
71 #define XILINX_DMA_DMACR_FRAMECNT_EN		BIT(4)
72 #define XILINX_DMA_DMACR_GENLOCK_EN		BIT(3)
73 #define XILINX_DMA_DMACR_RESET			BIT(2)
74 #define XILINX_DMA_DMACR_CIRC_EN		BIT(1)
75 #define XILINX_DMA_DMACR_RUNSTOP		BIT(0)
76 #define XILINX_DMA_DMACR_FSYNCSRC_MASK		GENMASK(6, 5)
77 #define XILINX_DMA_DMACR_DELAY_MASK		GENMASK(31, 24)
78 #define XILINX_DMA_DMACR_FRAME_COUNT_MASK	GENMASK(23, 16)
79 #define XILINX_DMA_DMACR_MASTER_MASK		GENMASK(11, 8)
80 
81 #define XILINX_DMA_REG_DMASR			0x0004
82 #define XILINX_DMA_DMASR_EOL_LATE_ERR		BIT(15)
83 #define XILINX_DMA_DMASR_ERR_IRQ		BIT(14)
84 #define XILINX_DMA_DMASR_DLY_CNT_IRQ		BIT(13)
85 #define XILINX_DMA_DMASR_FRM_CNT_IRQ		BIT(12)
86 #define XILINX_DMA_DMASR_SOF_LATE_ERR		BIT(11)
87 #define XILINX_DMA_DMASR_SG_DEC_ERR		BIT(10)
88 #define XILINX_DMA_DMASR_SG_SLV_ERR		BIT(9)
89 #define XILINX_DMA_DMASR_EOF_EARLY_ERR		BIT(8)
90 #define XILINX_DMA_DMASR_SOF_EARLY_ERR		BIT(7)
91 #define XILINX_DMA_DMASR_DMA_DEC_ERR		BIT(6)
92 #define XILINX_DMA_DMASR_DMA_SLAVE_ERR		BIT(5)
93 #define XILINX_DMA_DMASR_DMA_INT_ERR		BIT(4)
94 #define XILINX_DMA_DMASR_SG_MASK		BIT(3)
95 #define XILINX_DMA_DMASR_IDLE			BIT(1)
96 #define XILINX_DMA_DMASR_HALTED		BIT(0)
97 #define XILINX_DMA_DMASR_DELAY_MASK		GENMASK(31, 24)
98 #define XILINX_DMA_DMASR_FRAME_COUNT_MASK	GENMASK(23, 16)
99 
100 #define XILINX_DMA_REG_CURDESC			0x0008
101 #define XILINX_DMA_REG_TAILDESC		0x0010
102 #define XILINX_DMA_REG_REG_INDEX		0x0014
103 #define XILINX_DMA_REG_FRMSTORE		0x0018
104 #define XILINX_DMA_REG_THRESHOLD		0x001c
105 #define XILINX_DMA_REG_FRMPTR_STS		0x0024
106 #define XILINX_DMA_REG_PARK_PTR		0x0028
107 #define XILINX_DMA_PARK_PTR_WR_REF_SHIFT	8
108 #define XILINX_DMA_PARK_PTR_WR_REF_MASK		GENMASK(12, 8)
109 #define XILINX_DMA_PARK_PTR_RD_REF_SHIFT	0
110 #define XILINX_DMA_PARK_PTR_RD_REF_MASK		GENMASK(4, 0)
111 #define XILINX_DMA_REG_VDMA_VERSION		0x002c
112 
113 /* Register Direct Mode Registers */
114 #define XILINX_DMA_REG_VSIZE			0x0000
115 #define XILINX_DMA_VSIZE_MASK			GENMASK(12, 0)
116 #define XILINX_DMA_REG_HSIZE			0x0004
117 #define XILINX_DMA_HSIZE_MASK			GENMASK(15, 0)
118 
119 #define XILINX_DMA_REG_FRMDLY_STRIDE		0x0008
120 #define XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT	24
121 #define XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT	0
122 
123 #define XILINX_VDMA_REG_START_ADDRESS(n)	(0x000c + 4 * (n))
124 #define XILINX_VDMA_REG_START_ADDRESS_64(n)	(0x000c + 8 * (n))
125 
126 #define XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP	0x00ec
127 #define XILINX_VDMA_ENABLE_VERTICAL_FLIP	BIT(0)
128 
129 /* HW specific definitions */
130 #define XILINX_MCDMA_MAX_CHANS_PER_DEVICE	0x20
131 #define XILINX_DMA_MAX_CHANS_PER_DEVICE		0x2
132 #define XILINX_CDMA_MAX_CHANS_PER_DEVICE	0x1
133 
134 #define XILINX_DMA_DMAXR_ALL_IRQ_MASK	\
135 		(XILINX_DMA_DMASR_FRM_CNT_IRQ | \
136 		 XILINX_DMA_DMASR_DLY_CNT_IRQ | \
137 		 XILINX_DMA_DMASR_ERR_IRQ)
138 
139 #define XILINX_DMA_DMASR_ALL_ERR_MASK	\
140 		(XILINX_DMA_DMASR_EOL_LATE_ERR | \
141 		 XILINX_DMA_DMASR_SOF_LATE_ERR | \
142 		 XILINX_DMA_DMASR_SG_DEC_ERR | \
143 		 XILINX_DMA_DMASR_SG_SLV_ERR | \
144 		 XILINX_DMA_DMASR_EOF_EARLY_ERR | \
145 		 XILINX_DMA_DMASR_SOF_EARLY_ERR | \
146 		 XILINX_DMA_DMASR_DMA_DEC_ERR | \
147 		 XILINX_DMA_DMASR_DMA_SLAVE_ERR | \
148 		 XILINX_DMA_DMASR_DMA_INT_ERR)
149 
150 /*
151  * Recoverable errors are DMA Internal error, SOF Early, EOF Early
152  * and SOF Late. They are only recoverable when C_FLUSH_ON_FSYNC
153  * is enabled in the h/w system.
154  */
155 #define XILINX_DMA_DMASR_ERR_RECOVER_MASK	\
156 		(XILINX_DMA_DMASR_SOF_LATE_ERR | \
157 		 XILINX_DMA_DMASR_EOF_EARLY_ERR | \
158 		 XILINX_DMA_DMASR_SOF_EARLY_ERR | \
159 		 XILINX_DMA_DMASR_DMA_INT_ERR)
160 
161 /* Axi VDMA Flush on Fsync bits */
162 #define XILINX_DMA_FLUSH_S2MM		3
163 #define XILINX_DMA_FLUSH_MM2S		2
164 #define XILINX_DMA_FLUSH_BOTH		1
165 
166 /* Delay loop counter to prevent hardware failure */
167 #define XILINX_DMA_LOOP_COUNT		1000000
168 
169 /* AXI DMA Specific Registers/Offsets */
170 #define XILINX_DMA_REG_SRCDSTADDR	0x18
171 #define XILINX_DMA_REG_BTT		0x28
172 
173 /* AXI DMA Specific Masks/Bit fields */
174 #define XILINX_DMA_MAX_TRANS_LEN_MIN	8
175 #define XILINX_DMA_MAX_TRANS_LEN_MAX	23
176 #define XILINX_DMA_V2_MAX_TRANS_LEN_MAX	26
177 #define XILINX_DMA_CR_COALESCE_MAX	GENMASK(23, 16)
178 #define XILINX_DMA_CR_DELAY_MAX		GENMASK(31, 24)
179 #define XILINX_DMA_CR_CYCLIC_BD_EN_MASK	BIT(4)
180 #define XILINX_DMA_CR_COALESCE_SHIFT	16
181 #define XILINX_DMA_CR_DELAY_SHIFT	24
182 #define XILINX_DMA_BD_SOP		BIT(27)
183 #define XILINX_DMA_BD_EOP		BIT(26)
184 #define XILINX_DMA_BD_COMP_MASK		BIT(31)
185 #define XILINX_DMA_COALESCE_MAX		255
186 #define XILINX_DMA_NUM_DESCS		512
187 #define XILINX_DMA_NUM_APP_WORDS	5
188 
189 /* AXI CDMA Specific Registers/Offsets */
190 #define XILINX_CDMA_REG_SRCADDR		0x18
191 #define XILINX_CDMA_REG_DSTADDR		0x20
192 
193 /* AXI CDMA Specific Masks */
194 #define XILINX_CDMA_CR_SGMODE          BIT(3)
195 
196 #define xilinx_prep_dma_addr_t(addr)	\
197 	((dma_addr_t)((u64)addr##_##msb << 32 | (addr)))
198 
199 /* AXI MCDMA Specific Registers/Offsets */
200 #define XILINX_MCDMA_MM2S_CTRL_OFFSET		0x0000
201 #define XILINX_MCDMA_S2MM_CTRL_OFFSET		0x0500
202 #define XILINX_MCDMA_CHEN_OFFSET		0x0008
203 #define XILINX_MCDMA_CH_ERR_OFFSET		0x0010
204 #define XILINX_MCDMA_RXINT_SER_OFFSET		0x0020
205 #define XILINX_MCDMA_TXINT_SER_OFFSET		0x0028
206 #define XILINX_MCDMA_CHAN_CR_OFFSET(x)		(0x40 + (x) * 0x40)
207 #define XILINX_MCDMA_CHAN_SR_OFFSET(x)		(0x44 + (x) * 0x40)
208 #define XILINX_MCDMA_CHAN_CDESC_OFFSET(x)	(0x48 + (x) * 0x40)
209 #define XILINX_MCDMA_CHAN_TDESC_OFFSET(x)	(0x50 + (x) * 0x40)
210 
211 /* AXI MCDMA Specific Masks/Shifts */
212 #define XILINX_MCDMA_COALESCE_SHIFT		16
213 #define XILINX_MCDMA_COALESCE_MAX		24
214 #define XILINX_MCDMA_IRQ_ALL_MASK		GENMASK(7, 5)
215 #define XILINX_MCDMA_COALESCE_MASK		GENMASK(23, 16)
216 #define XILINX_MCDMA_CR_RUNSTOP_MASK		BIT(0)
217 #define XILINX_MCDMA_IRQ_IOC_MASK		BIT(5)
218 #define XILINX_MCDMA_IRQ_DELAY_MASK		BIT(6)
219 #define XILINX_MCDMA_IRQ_ERR_MASK		BIT(7)
220 #define XILINX_MCDMA_BD_EOP			BIT(30)
221 #define XILINX_MCDMA_BD_SOP			BIT(31)
222 
223 /**
224  * struct xilinx_vdma_desc_hw - Hardware Descriptor
225  * @next_desc: Next Descriptor Pointer @0x00
226  * @pad1: Reserved @0x04
227  * @buf_addr: Buffer address @0x08
228  * @buf_addr_msb: MSB of Buffer address @0x0C
229  * @vsize: Vertical Size @0x10
230  * @hsize: Horizontal Size @0x14
231  * @stride: Number of bytes between the first
232  *	    pixels of each horizontal line @0x18
233  */
234 struct xilinx_vdma_desc_hw {
235 	u32 next_desc;
236 	u32 pad1;
237 	u32 buf_addr;
238 	u32 buf_addr_msb;
239 	u32 vsize;
240 	u32 hsize;
241 	u32 stride;
242 } __aligned(64);
243 
244 /**
245  * struct xilinx_axidma_desc_hw - Hardware Descriptor for AXI DMA
246  * @next_desc: Next Descriptor Pointer @0x00
247  * @next_desc_msb: MSB of Next Descriptor Pointer @0x04
248  * @buf_addr: Buffer address @0x08
249  * @buf_addr_msb: MSB of Buffer address @0x0C
250  * @reserved1: Reserved @0x10
251  * @reserved2: Reserved @0x14
252  * @control: Control field @0x18
253  * @status: Status field @0x1C
254  * @app: APP Fields @0x20 - 0x30
255  */
256 struct xilinx_axidma_desc_hw {
257 	u32 next_desc;
258 	u32 next_desc_msb;
259 	u32 buf_addr;
260 	u32 buf_addr_msb;
261 	u32 reserved1;
262 	u32 reserved2;
263 	u32 control;
264 	u32 status;
265 	u32 app[XILINX_DMA_NUM_APP_WORDS];
266 } __aligned(64);
267 
268 /**
269  * struct xilinx_aximcdma_desc_hw - Hardware Descriptor for AXI MCDMA
270  * @next_desc: Next Descriptor Pointer @0x00
271  * @next_desc_msb: MSB of Next Descriptor Pointer @0x04
272  * @buf_addr: Buffer address @0x08
273  * @buf_addr_msb: MSB of Buffer address @0x0C
274  * @rsvd: Reserved field @0x10
275  * @control: Control Information field @0x14
276  * @status: Status field @0x18
277  * @sideband_status: Status of sideband signals @0x1C
278  * @app: APP Fields @0x20 - 0x30
279  */
280 struct xilinx_aximcdma_desc_hw {
281 	u32 next_desc;
282 	u32 next_desc_msb;
283 	u32 buf_addr;
284 	u32 buf_addr_msb;
285 	u32 rsvd;
286 	u32 control;
287 	u32 status;
288 	u32 sideband_status;
289 	u32 app[XILINX_DMA_NUM_APP_WORDS];
290 } __aligned(64);
291 
292 /**
293  * struct xilinx_cdma_desc_hw - Hardware Descriptor
294  * @next_desc: Next Descriptor Pointer @0x00
295  * @next_desc_msb: Next Descriptor Pointer MSB @0x04
296  * @src_addr: Source address @0x08
297  * @src_addr_msb: Source address MSB @0x0C
298  * @dest_addr: Destination address @0x10
299  * @dest_addr_msb: Destination address MSB @0x14
300  * @control: Control field @0x18
301  * @status: Status field @0x1C
302  */
303 struct xilinx_cdma_desc_hw {
304 	u32 next_desc;
305 	u32 next_desc_msb;
306 	u32 src_addr;
307 	u32 src_addr_msb;
308 	u32 dest_addr;
309 	u32 dest_addr_msb;
310 	u32 control;
311 	u32 status;
312 } __aligned(64);
313 
314 /**
315  * struct xilinx_vdma_tx_segment - Descriptor segment
316  * @hw: Hardware descriptor
317  * @node: Node in the descriptor segments list
318  * @phys: Physical address of segment
319  */
320 struct xilinx_vdma_tx_segment {
321 	struct xilinx_vdma_desc_hw hw;
322 	struct list_head node;
323 	dma_addr_t phys;
324 } __aligned(64);
325 
326 /**
327  * struct xilinx_axidma_tx_segment - Descriptor segment
328  * @hw: Hardware descriptor
329  * @node: Node in the descriptor segments list
330  * @phys: Physical address of segment
331  */
332 struct xilinx_axidma_tx_segment {
333 	struct xilinx_axidma_desc_hw hw;
334 	struct list_head node;
335 	dma_addr_t phys;
336 } __aligned(64);
337 
338 /**
339  * struct xilinx_aximcdma_tx_segment - Descriptor segment
340  * @hw: Hardware descriptor
341  * @node: Node in the descriptor segments list
342  * @phys: Physical address of segment
343  */
344 struct xilinx_aximcdma_tx_segment {
345 	struct xilinx_aximcdma_desc_hw hw;
346 	struct list_head node;
347 	dma_addr_t phys;
348 } __aligned(64);
349 
350 /**
351  * struct xilinx_cdma_tx_segment - Descriptor segment
352  * @hw: Hardware descriptor
353  * @node: Node in the descriptor segments list
354  * @phys: Physical address of segment
355  */
356 struct xilinx_cdma_tx_segment {
357 	struct xilinx_cdma_desc_hw hw;
358 	struct list_head node;
359 	dma_addr_t phys;
360 } __aligned(64);
361 
362 /**
363  * struct xilinx_dma_tx_descriptor - Per Transaction structure
364  * @async_tx: Async transaction descriptor
365  * @segments: TX segments list
366  * @node: Node in the channel descriptors list
367  * @cyclic: Check for cyclic transfers.
368  * @err: Whether the descriptor has an error.
369  * @residue: Residue of the completed descriptor
370  */
371 struct xilinx_dma_tx_descriptor {
372 	struct dma_async_tx_descriptor async_tx;
373 	struct list_head segments;
374 	struct list_head node;
375 	bool cyclic;
376 	bool err;
377 	u32 residue;
378 };
379 
380 /**
381  * struct xilinx_dma_chan - Driver specific DMA channel structure
382  * @xdev: Driver specific device structure
383  * @ctrl_offset: Control registers offset
384  * @desc_offset: TX descriptor registers offset
385  * @lock: Descriptor operation lock
386  * @pending_list: Descriptors waiting
387  * @active_list: Descriptors ready to submit
388  * @done_list: Complete descriptors
389  * @free_seg_list: Free descriptors
390  * @common: DMA common channel
391  * @desc_pool: Descriptors pool
392  * @dev: The dma device
393  * @irq: Channel IRQ
394  * @id: Channel ID
395  * @direction: Transfer direction
396  * @num_frms: Number of frames
397  * @has_sg: Support scatter transfers
398  * @cyclic: Check for cyclic transfers.
399  * @genlock: Support genlock mode
400  * @err: Channel has errors
401  * @idle: Check for channel idle
402  * @terminating: Check for channel being synchronized by user
403  * @tasklet: Cleanup work after irq
404  * @config: Device configuration info
405  * @flush_on_fsync: Flush on Frame sync
406  * @desc_pendingcount: Descriptor pending count
407  * @ext_addr: Indicates 64 bit addressing is supported by dma channel
408  * @desc_submitcount: Descriptor h/w submitted count
409  * @seg_v: Statically allocated segments base
410  * @seg_mv: Statically allocated segments base for MCDMA
411  * @seg_p: Physical allocated segments base
412  * @cyclic_seg_v: Statically allocated segment base for cyclic transfers
413  * @cyclic_seg_p: Physical allocated segments base for cyclic dma
414  * @start_transfer: Differentiate b/w DMA IP's transfer
415  * @stop_transfer: Differentiate b/w DMA IP's quiesce
416  * @tdest: TDEST value for mcdma
417  * @has_vflip: S2MM vertical flip
418  * @irq_delay: Interrupt delay timeout
419  */
420 struct xilinx_dma_chan {
421 	struct xilinx_dma_device *xdev;
422 	u32 ctrl_offset;
423 	u32 desc_offset;
424 	spinlock_t lock;
425 	struct list_head pending_list;
426 	struct list_head active_list;
427 	struct list_head done_list;
428 	struct list_head free_seg_list;
429 	struct dma_chan common;
430 	struct dma_pool *desc_pool;
431 	struct device *dev;
432 	int irq;
433 	int id;
434 	enum dma_transfer_direction direction;
435 	int num_frms;
436 	bool has_sg;
437 	bool cyclic;
438 	bool genlock;
439 	bool err;
440 	bool idle;
441 	bool terminating;
442 	struct tasklet_struct tasklet;
443 	struct xilinx_vdma_config config;
444 	bool flush_on_fsync;
445 	u32 desc_pendingcount;
446 	bool ext_addr;
447 	u32 desc_submitcount;
448 	struct xilinx_axidma_tx_segment *seg_v;
449 	struct xilinx_aximcdma_tx_segment *seg_mv;
450 	dma_addr_t seg_p;
451 	struct xilinx_axidma_tx_segment *cyclic_seg_v;
452 	dma_addr_t cyclic_seg_p;
453 	void (*start_transfer)(struct xilinx_dma_chan *chan);
454 	int (*stop_transfer)(struct xilinx_dma_chan *chan);
455 	u16 tdest;
456 	bool has_vflip;
457 	u8 irq_delay;
458 };
459 
460 /**
461  * enum xdma_ip_type - DMA IP type.
462  *
463  * @XDMA_TYPE_AXIDMA: Axi dma ip.
464  * @XDMA_TYPE_CDMA: Axi cdma ip.
465  * @XDMA_TYPE_VDMA: Axi vdma ip.
466  * @XDMA_TYPE_AXIMCDMA: Axi MCDMA ip.
467  *
468  */
469 enum xdma_ip_type {
470 	XDMA_TYPE_AXIDMA = 0,
471 	XDMA_TYPE_CDMA,
472 	XDMA_TYPE_VDMA,
473 	XDMA_TYPE_AXIMCDMA
474 };
475 
476 struct xilinx_dma_config {
477 	enum xdma_ip_type dmatype;
478 	int (*clk_init)(struct platform_device *pdev, struct clk **axi_clk,
479 			struct clk **tx_clk, struct clk **txs_clk,
480 			struct clk **rx_clk, struct clk **rxs_clk);
481 	irqreturn_t (*irq_handler)(int irq, void *data);
482 	const int max_channels;
483 };
484 
485 /**
486  * struct xilinx_dma_device - DMA device structure
487  * @regs: I/O mapped base address
488  * @dev: Device Structure
489  * @common: DMA device structure
490  * @chan: Driver specific DMA channel
491  * @flush_on_fsync: Flush on frame sync
492  * @ext_addr: Indicates 64 bit addressing is supported by dma device
493  * @pdev: Platform device structure pointer
494  * @dma_config: DMA config structure
495  * @axi_clk: DMA Axi4-lite interace clock
496  * @tx_clk: DMA mm2s clock
497  * @txs_clk: DMA mm2s stream clock
498  * @rx_clk: DMA s2mm clock
499  * @rxs_clk: DMA s2mm stream clock
500  * @s2mm_chan_id: DMA s2mm channel identifier
501  * @mm2s_chan_id: DMA mm2s channel identifier
502  * @max_buffer_len: Max buffer length
503  * @has_axistream_connected: AXI DMA connected to AXI Stream IP
504  */
505 struct xilinx_dma_device {
506 	void __iomem *regs;
507 	struct device *dev;
508 	struct dma_device common;
509 	struct xilinx_dma_chan *chan[XILINX_MCDMA_MAX_CHANS_PER_DEVICE];
510 	u32 flush_on_fsync;
511 	bool ext_addr;
512 	struct platform_device  *pdev;
513 	const struct xilinx_dma_config *dma_config;
514 	struct clk *axi_clk;
515 	struct clk *tx_clk;
516 	struct clk *txs_clk;
517 	struct clk *rx_clk;
518 	struct clk *rxs_clk;
519 	u32 s2mm_chan_id;
520 	u32 mm2s_chan_id;
521 	u32 max_buffer_len;
522 	bool has_axistream_connected;
523 };
524 
525 /* Macros */
526 #define to_xilinx_chan(chan) \
527 	container_of(chan, struct xilinx_dma_chan, common)
528 #define to_dma_tx_descriptor(tx) \
529 	container_of(tx, struct xilinx_dma_tx_descriptor, async_tx)
530 #define xilinx_dma_poll_timeout(chan, reg, val, cond, delay_us, timeout_us) \
531 	readl_poll_timeout_atomic(chan->xdev->regs + chan->ctrl_offset + reg, \
532 				  val, cond, delay_us, timeout_us)
533 
534 /* IO accessors */
535 static inline u32 dma_read(struct xilinx_dma_chan *chan, u32 reg)
536 {
537 	return ioread32(chan->xdev->regs + reg);
538 }
539 
540 static inline void dma_write(struct xilinx_dma_chan *chan, u32 reg, u32 value)
541 {
542 	iowrite32(value, chan->xdev->regs + reg);
543 }
544 
545 static inline void vdma_desc_write(struct xilinx_dma_chan *chan, u32 reg,
546 				   u32 value)
547 {
548 	dma_write(chan, chan->desc_offset + reg, value);
549 }
550 
551 static inline u32 dma_ctrl_read(struct xilinx_dma_chan *chan, u32 reg)
552 {
553 	return dma_read(chan, chan->ctrl_offset + reg);
554 }
555 
556 static inline void dma_ctrl_write(struct xilinx_dma_chan *chan, u32 reg,
557 				   u32 value)
558 {
559 	dma_write(chan, chan->ctrl_offset + reg, value);
560 }
561 
562 static inline void dma_ctrl_clr(struct xilinx_dma_chan *chan, u32 reg,
563 				 u32 clr)
564 {
565 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) & ~clr);
566 }
567 
568 static inline void dma_ctrl_set(struct xilinx_dma_chan *chan, u32 reg,
569 				 u32 set)
570 {
571 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) | set);
572 }
573 
574 /**
575  * vdma_desc_write_64 - 64-bit descriptor write
576  * @chan: Driver specific VDMA channel
577  * @reg: Register to write
578  * @value_lsb: lower address of the descriptor.
579  * @value_msb: upper address of the descriptor.
580  *
581  * Since vdma driver is trying to write to a register offset which is not a
582  * multiple of 64 bits(ex : 0x5c), we are writing as two separate 32 bits
583  * instead of a single 64 bit register write.
584  */
585 static inline void vdma_desc_write_64(struct xilinx_dma_chan *chan, u32 reg,
586 				      u32 value_lsb, u32 value_msb)
587 {
588 	/* Write the lsb 32 bits*/
589 	writel(value_lsb, chan->xdev->regs + chan->desc_offset + reg);
590 
591 	/* Write the msb 32 bits */
592 	writel(value_msb, chan->xdev->regs + chan->desc_offset + reg + 4);
593 }
594 
595 static inline void dma_writeq(struct xilinx_dma_chan *chan, u32 reg, u64 value)
596 {
597 	lo_hi_writeq(value, chan->xdev->regs + chan->ctrl_offset + reg);
598 }
599 
600 static inline void xilinx_write(struct xilinx_dma_chan *chan, u32 reg,
601 				dma_addr_t addr)
602 {
603 	if (chan->ext_addr)
604 		dma_writeq(chan, reg, addr);
605 	else
606 		dma_ctrl_write(chan, reg, addr);
607 }
608 
609 static inline void xilinx_axidma_buf(struct xilinx_dma_chan *chan,
610 				     struct xilinx_axidma_desc_hw *hw,
611 				     dma_addr_t buf_addr, size_t sg_used,
612 				     size_t period_len)
613 {
614 	if (chan->ext_addr) {
615 		hw->buf_addr = lower_32_bits(buf_addr + sg_used + period_len);
616 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used +
617 						 period_len);
618 	} else {
619 		hw->buf_addr = buf_addr + sg_used + period_len;
620 	}
621 }
622 
623 static inline void xilinx_aximcdma_buf(struct xilinx_dma_chan *chan,
624 				       struct xilinx_aximcdma_desc_hw *hw,
625 				       dma_addr_t buf_addr, size_t sg_used)
626 {
627 	if (chan->ext_addr) {
628 		hw->buf_addr = lower_32_bits(buf_addr + sg_used);
629 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used);
630 	} else {
631 		hw->buf_addr = buf_addr + sg_used;
632 	}
633 }
634 
635 /**
636  * xilinx_dma_get_metadata_ptr- Populate metadata pointer and payload length
637  * @tx: async transaction descriptor
638  * @payload_len: metadata payload length
639  * @max_len: metadata max length
640  * Return: The app field pointer.
641  */
642 static void *xilinx_dma_get_metadata_ptr(struct dma_async_tx_descriptor *tx,
643 					 size_t *payload_len, size_t *max_len)
644 {
645 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
646 	struct xilinx_axidma_tx_segment *seg;
647 
648 	*max_len = *payload_len = sizeof(u32) * XILINX_DMA_NUM_APP_WORDS;
649 	seg = list_first_entry(&desc->segments,
650 			       struct xilinx_axidma_tx_segment, node);
651 	return seg->hw.app;
652 }
653 
654 static struct dma_descriptor_metadata_ops xilinx_dma_metadata_ops = {
655 	.get_ptr = xilinx_dma_get_metadata_ptr,
656 };
657 
658 /* -----------------------------------------------------------------------------
659  * Descriptors and segments alloc and free
660  */
661 
662 /**
663  * xilinx_vdma_alloc_tx_segment - Allocate transaction segment
664  * @chan: Driver specific DMA channel
665  *
666  * Return: The allocated segment on success and NULL on failure.
667  */
668 static struct xilinx_vdma_tx_segment *
669 xilinx_vdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
670 {
671 	struct xilinx_vdma_tx_segment *segment;
672 	dma_addr_t phys;
673 
674 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
675 	if (!segment)
676 		return NULL;
677 
678 	segment->phys = phys;
679 
680 	return segment;
681 }
682 
683 /**
684  * xilinx_cdma_alloc_tx_segment - Allocate transaction segment
685  * @chan: Driver specific DMA channel
686  *
687  * Return: The allocated segment on success and NULL on failure.
688  */
689 static struct xilinx_cdma_tx_segment *
690 xilinx_cdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
691 {
692 	struct xilinx_cdma_tx_segment *segment;
693 	dma_addr_t phys;
694 
695 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
696 	if (!segment)
697 		return NULL;
698 
699 	segment->phys = phys;
700 
701 	return segment;
702 }
703 
704 /**
705  * xilinx_axidma_alloc_tx_segment - Allocate transaction segment
706  * @chan: Driver specific DMA channel
707  *
708  * Return: The allocated segment on success and NULL on failure.
709  */
710 static struct xilinx_axidma_tx_segment *
711 xilinx_axidma_alloc_tx_segment(struct xilinx_dma_chan *chan)
712 {
713 	struct xilinx_axidma_tx_segment *segment = NULL;
714 	unsigned long flags;
715 
716 	spin_lock_irqsave(&chan->lock, flags);
717 	if (!list_empty(&chan->free_seg_list)) {
718 		segment = list_first_entry(&chan->free_seg_list,
719 					   struct xilinx_axidma_tx_segment,
720 					   node);
721 		list_del(&segment->node);
722 	}
723 	spin_unlock_irqrestore(&chan->lock, flags);
724 
725 	if (!segment)
726 		dev_dbg(chan->dev, "Could not find free tx segment\n");
727 
728 	return segment;
729 }
730 
731 /**
732  * xilinx_aximcdma_alloc_tx_segment - Allocate transaction segment
733  * @chan: Driver specific DMA channel
734  *
735  * Return: The allocated segment on success and NULL on failure.
736  */
737 static struct xilinx_aximcdma_tx_segment *
738 xilinx_aximcdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
739 {
740 	struct xilinx_aximcdma_tx_segment *segment = NULL;
741 	unsigned long flags;
742 
743 	spin_lock_irqsave(&chan->lock, flags);
744 	if (!list_empty(&chan->free_seg_list)) {
745 		segment = list_first_entry(&chan->free_seg_list,
746 					   struct xilinx_aximcdma_tx_segment,
747 					   node);
748 		list_del(&segment->node);
749 	}
750 	spin_unlock_irqrestore(&chan->lock, flags);
751 
752 	return segment;
753 }
754 
755 static void xilinx_dma_clean_hw_desc(struct xilinx_axidma_desc_hw *hw)
756 {
757 	u32 next_desc = hw->next_desc;
758 	u32 next_desc_msb = hw->next_desc_msb;
759 
760 	memset(hw, 0, sizeof(struct xilinx_axidma_desc_hw));
761 
762 	hw->next_desc = next_desc;
763 	hw->next_desc_msb = next_desc_msb;
764 }
765 
766 static void xilinx_mcdma_clean_hw_desc(struct xilinx_aximcdma_desc_hw *hw)
767 {
768 	u32 next_desc = hw->next_desc;
769 	u32 next_desc_msb = hw->next_desc_msb;
770 
771 	memset(hw, 0, sizeof(struct xilinx_aximcdma_desc_hw));
772 
773 	hw->next_desc = next_desc;
774 	hw->next_desc_msb = next_desc_msb;
775 }
776 
777 /**
778  * xilinx_dma_free_tx_segment - Free transaction segment
779  * @chan: Driver specific DMA channel
780  * @segment: DMA transaction segment
781  */
782 static void xilinx_dma_free_tx_segment(struct xilinx_dma_chan *chan,
783 				struct xilinx_axidma_tx_segment *segment)
784 {
785 	xilinx_dma_clean_hw_desc(&segment->hw);
786 
787 	list_add_tail(&segment->node, &chan->free_seg_list);
788 }
789 
790 /**
791  * xilinx_mcdma_free_tx_segment - Free transaction segment
792  * @chan: Driver specific DMA channel
793  * @segment: DMA transaction segment
794  */
795 static void xilinx_mcdma_free_tx_segment(struct xilinx_dma_chan *chan,
796 					 struct xilinx_aximcdma_tx_segment *
797 					 segment)
798 {
799 	xilinx_mcdma_clean_hw_desc(&segment->hw);
800 
801 	list_add_tail(&segment->node, &chan->free_seg_list);
802 }
803 
804 /**
805  * xilinx_cdma_free_tx_segment - Free transaction segment
806  * @chan: Driver specific DMA channel
807  * @segment: DMA transaction segment
808  */
809 static void xilinx_cdma_free_tx_segment(struct xilinx_dma_chan *chan,
810 				struct xilinx_cdma_tx_segment *segment)
811 {
812 	dma_pool_free(chan->desc_pool, segment, segment->phys);
813 }
814 
815 /**
816  * xilinx_vdma_free_tx_segment - Free transaction segment
817  * @chan: Driver specific DMA channel
818  * @segment: DMA transaction segment
819  */
820 static void xilinx_vdma_free_tx_segment(struct xilinx_dma_chan *chan,
821 					struct xilinx_vdma_tx_segment *segment)
822 {
823 	dma_pool_free(chan->desc_pool, segment, segment->phys);
824 }
825 
826 /**
827  * xilinx_dma_alloc_tx_descriptor - Allocate transaction descriptor
828  * @chan: Driver specific DMA channel
829  *
830  * Return: The allocated descriptor on success and NULL on failure.
831  */
832 static struct xilinx_dma_tx_descriptor *
833 xilinx_dma_alloc_tx_descriptor(struct xilinx_dma_chan *chan)
834 {
835 	struct xilinx_dma_tx_descriptor *desc;
836 
837 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
838 	if (!desc)
839 		return NULL;
840 
841 	INIT_LIST_HEAD(&desc->segments);
842 
843 	return desc;
844 }
845 
846 /**
847  * xilinx_dma_free_tx_descriptor - Free transaction descriptor
848  * @chan: Driver specific DMA channel
849  * @desc: DMA transaction descriptor
850  */
851 static void
852 xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
853 			       struct xilinx_dma_tx_descriptor *desc)
854 {
855 	struct xilinx_vdma_tx_segment *segment, *next;
856 	struct xilinx_cdma_tx_segment *cdma_segment, *cdma_next;
857 	struct xilinx_axidma_tx_segment *axidma_segment, *axidma_next;
858 	struct xilinx_aximcdma_tx_segment *aximcdma_segment, *aximcdma_next;
859 
860 	if (!desc)
861 		return;
862 
863 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
864 		list_for_each_entry_safe(segment, next, &desc->segments, node) {
865 			list_del(&segment->node);
866 			xilinx_vdma_free_tx_segment(chan, segment);
867 		}
868 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
869 		list_for_each_entry_safe(cdma_segment, cdma_next,
870 					 &desc->segments, node) {
871 			list_del(&cdma_segment->node);
872 			xilinx_cdma_free_tx_segment(chan, cdma_segment);
873 		}
874 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
875 		list_for_each_entry_safe(axidma_segment, axidma_next,
876 					 &desc->segments, node) {
877 			list_del(&axidma_segment->node);
878 			xilinx_dma_free_tx_segment(chan, axidma_segment);
879 		}
880 	} else {
881 		list_for_each_entry_safe(aximcdma_segment, aximcdma_next,
882 					 &desc->segments, node) {
883 			list_del(&aximcdma_segment->node);
884 			xilinx_mcdma_free_tx_segment(chan, aximcdma_segment);
885 		}
886 	}
887 
888 	kfree(desc);
889 }
890 
891 /* Required functions */
892 
893 /**
894  * xilinx_dma_free_desc_list - Free descriptors list
895  * @chan: Driver specific DMA channel
896  * @list: List to parse and delete the descriptor
897  */
898 static void xilinx_dma_free_desc_list(struct xilinx_dma_chan *chan,
899 					struct list_head *list)
900 {
901 	struct xilinx_dma_tx_descriptor *desc, *next;
902 
903 	list_for_each_entry_safe(desc, next, list, node) {
904 		list_del(&desc->node);
905 		xilinx_dma_free_tx_descriptor(chan, desc);
906 	}
907 }
908 
909 /**
910  * xilinx_dma_free_descriptors - Free channel descriptors
911  * @chan: Driver specific DMA channel
912  */
913 static void xilinx_dma_free_descriptors(struct xilinx_dma_chan *chan)
914 {
915 	unsigned long flags;
916 
917 	spin_lock_irqsave(&chan->lock, flags);
918 
919 	xilinx_dma_free_desc_list(chan, &chan->pending_list);
920 	xilinx_dma_free_desc_list(chan, &chan->done_list);
921 	xilinx_dma_free_desc_list(chan, &chan->active_list);
922 
923 	spin_unlock_irqrestore(&chan->lock, flags);
924 }
925 
926 /**
927  * xilinx_dma_free_chan_resources - Free channel resources
928  * @dchan: DMA channel
929  */
930 static void xilinx_dma_free_chan_resources(struct dma_chan *dchan)
931 {
932 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
933 	unsigned long flags;
934 
935 	dev_dbg(chan->dev, "Free all channel resources.\n");
936 
937 	xilinx_dma_free_descriptors(chan);
938 
939 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
940 		spin_lock_irqsave(&chan->lock, flags);
941 		INIT_LIST_HEAD(&chan->free_seg_list);
942 		spin_unlock_irqrestore(&chan->lock, flags);
943 
944 		/* Free memory that is allocated for BD */
945 		dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
946 				  XILINX_DMA_NUM_DESCS, chan->seg_v,
947 				  chan->seg_p);
948 
949 		/* Free Memory that is allocated for cyclic DMA Mode */
950 		dma_free_coherent(chan->dev, sizeof(*chan->cyclic_seg_v),
951 				  chan->cyclic_seg_v, chan->cyclic_seg_p);
952 	}
953 
954 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
955 		spin_lock_irqsave(&chan->lock, flags);
956 		INIT_LIST_HEAD(&chan->free_seg_list);
957 		spin_unlock_irqrestore(&chan->lock, flags);
958 
959 		/* Free memory that is allocated for BD */
960 		dma_free_coherent(chan->dev, sizeof(*chan->seg_mv) *
961 				  XILINX_DMA_NUM_DESCS, chan->seg_mv,
962 				  chan->seg_p);
963 	}
964 
965 	if (chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA &&
966 	    chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA) {
967 		dma_pool_destroy(chan->desc_pool);
968 		chan->desc_pool = NULL;
969 	}
970 
971 }
972 
973 /**
974  * xilinx_dma_get_residue - Compute residue for a given descriptor
975  * @chan: Driver specific dma channel
976  * @desc: dma transaction descriptor
977  *
978  * Return: The number of residue bytes for the descriptor.
979  */
980 static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
981 				  struct xilinx_dma_tx_descriptor *desc)
982 {
983 	struct xilinx_cdma_tx_segment *cdma_seg;
984 	struct xilinx_axidma_tx_segment *axidma_seg;
985 	struct xilinx_aximcdma_tx_segment *aximcdma_seg;
986 	struct xilinx_cdma_desc_hw *cdma_hw;
987 	struct xilinx_axidma_desc_hw *axidma_hw;
988 	struct xilinx_aximcdma_desc_hw *aximcdma_hw;
989 	struct list_head *entry;
990 	u32 residue = 0;
991 
992 	list_for_each(entry, &desc->segments) {
993 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
994 			cdma_seg = list_entry(entry,
995 					      struct xilinx_cdma_tx_segment,
996 					      node);
997 			cdma_hw = &cdma_seg->hw;
998 			residue += (cdma_hw->control - cdma_hw->status) &
999 				   chan->xdev->max_buffer_len;
1000 		} else if (chan->xdev->dma_config->dmatype ==
1001 			   XDMA_TYPE_AXIDMA) {
1002 			axidma_seg = list_entry(entry,
1003 						struct xilinx_axidma_tx_segment,
1004 						node);
1005 			axidma_hw = &axidma_seg->hw;
1006 			residue += (axidma_hw->control - axidma_hw->status) &
1007 				   chan->xdev->max_buffer_len;
1008 		} else {
1009 			aximcdma_seg =
1010 				list_entry(entry,
1011 					   struct xilinx_aximcdma_tx_segment,
1012 					   node);
1013 			aximcdma_hw = &aximcdma_seg->hw;
1014 			residue +=
1015 				(aximcdma_hw->control - aximcdma_hw->status) &
1016 				chan->xdev->max_buffer_len;
1017 		}
1018 	}
1019 
1020 	return residue;
1021 }
1022 
1023 /**
1024  * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
1025  * @chan: Driver specific dma channel
1026  * @desc: dma transaction descriptor
1027  * @flags: flags for spin lock
1028  */
1029 static void xilinx_dma_chan_handle_cyclic(struct xilinx_dma_chan *chan,
1030 					  struct xilinx_dma_tx_descriptor *desc,
1031 					  unsigned long *flags)
1032 {
1033 	struct dmaengine_desc_callback cb;
1034 
1035 	dmaengine_desc_get_callback(&desc->async_tx, &cb);
1036 	if (dmaengine_desc_callback_valid(&cb)) {
1037 		spin_unlock_irqrestore(&chan->lock, *flags);
1038 		dmaengine_desc_callback_invoke(&cb, NULL);
1039 		spin_lock_irqsave(&chan->lock, *flags);
1040 	}
1041 }
1042 
1043 /**
1044  * xilinx_dma_chan_desc_cleanup - Clean channel descriptors
1045  * @chan: Driver specific DMA channel
1046  */
1047 static void xilinx_dma_chan_desc_cleanup(struct xilinx_dma_chan *chan)
1048 {
1049 	struct xilinx_dma_tx_descriptor *desc, *next;
1050 	unsigned long flags;
1051 
1052 	spin_lock_irqsave(&chan->lock, flags);
1053 
1054 	list_for_each_entry_safe(desc, next, &chan->done_list, node) {
1055 		struct dmaengine_result result;
1056 
1057 		if (desc->cyclic) {
1058 			xilinx_dma_chan_handle_cyclic(chan, desc, &flags);
1059 			break;
1060 		}
1061 
1062 		/* Remove from the list of running transactions */
1063 		list_del(&desc->node);
1064 
1065 		if (unlikely(desc->err)) {
1066 			if (chan->direction == DMA_DEV_TO_MEM)
1067 				result.result = DMA_TRANS_READ_FAILED;
1068 			else
1069 				result.result = DMA_TRANS_WRITE_FAILED;
1070 		} else {
1071 			result.result = DMA_TRANS_NOERROR;
1072 		}
1073 
1074 		result.residue = desc->residue;
1075 
1076 		/* Run the link descriptor callback function */
1077 		spin_unlock_irqrestore(&chan->lock, flags);
1078 		dmaengine_desc_get_callback_invoke(&desc->async_tx, &result);
1079 		spin_lock_irqsave(&chan->lock, flags);
1080 
1081 		/* Run any dependencies, then free the descriptor */
1082 		dma_run_dependencies(&desc->async_tx);
1083 		xilinx_dma_free_tx_descriptor(chan, desc);
1084 
1085 		/*
1086 		 * While we ran a callback the user called a terminate function,
1087 		 * which takes care of cleaning up any remaining descriptors
1088 		 */
1089 		if (chan->terminating)
1090 			break;
1091 	}
1092 
1093 	spin_unlock_irqrestore(&chan->lock, flags);
1094 }
1095 
1096 /**
1097  * xilinx_dma_do_tasklet - Schedule completion tasklet
1098  * @t: Pointer to the Xilinx DMA channel structure
1099  */
1100 static void xilinx_dma_do_tasklet(struct tasklet_struct *t)
1101 {
1102 	struct xilinx_dma_chan *chan = from_tasklet(chan, t, tasklet);
1103 
1104 	xilinx_dma_chan_desc_cleanup(chan);
1105 }
1106 
1107 /**
1108  * xilinx_dma_alloc_chan_resources - Allocate channel resources
1109  * @dchan: DMA channel
1110  *
1111  * Return: '0' on success and failure value on error
1112  */
1113 static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
1114 {
1115 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1116 	int i;
1117 
1118 	/* Has this channel already been allocated? */
1119 	if (chan->desc_pool)
1120 		return 0;
1121 
1122 	/*
1123 	 * We need the descriptor to be aligned to 64bytes
1124 	 * for meeting Xilinx VDMA specification requirement.
1125 	 */
1126 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1127 		/* Allocate the buffer descriptors. */
1128 		chan->seg_v = dma_alloc_coherent(chan->dev,
1129 						 sizeof(*chan->seg_v) * XILINX_DMA_NUM_DESCS,
1130 						 &chan->seg_p, GFP_KERNEL);
1131 		if (!chan->seg_v) {
1132 			dev_err(chan->dev,
1133 				"unable to allocate channel %d descriptors\n",
1134 				chan->id);
1135 			return -ENOMEM;
1136 		}
1137 		/*
1138 		 * For cyclic DMA mode we need to program the tail Descriptor
1139 		 * register with a value which is not a part of the BD chain
1140 		 * so allocating a desc segment during channel allocation for
1141 		 * programming tail descriptor.
1142 		 */
1143 		chan->cyclic_seg_v = dma_alloc_coherent(chan->dev,
1144 							sizeof(*chan->cyclic_seg_v),
1145 							&chan->cyclic_seg_p,
1146 							GFP_KERNEL);
1147 		if (!chan->cyclic_seg_v) {
1148 			dev_err(chan->dev,
1149 				"unable to allocate desc segment for cyclic DMA\n");
1150 			dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
1151 				XILINX_DMA_NUM_DESCS, chan->seg_v,
1152 				chan->seg_p);
1153 			return -ENOMEM;
1154 		}
1155 		chan->cyclic_seg_v->phys = chan->cyclic_seg_p;
1156 
1157 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1158 			chan->seg_v[i].hw.next_desc =
1159 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1160 				((i + 1) % XILINX_DMA_NUM_DESCS));
1161 			chan->seg_v[i].hw.next_desc_msb =
1162 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1163 				((i + 1) % XILINX_DMA_NUM_DESCS));
1164 			chan->seg_v[i].phys = chan->seg_p +
1165 				sizeof(*chan->seg_v) * i;
1166 			list_add_tail(&chan->seg_v[i].node,
1167 				      &chan->free_seg_list);
1168 		}
1169 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
1170 		/* Allocate the buffer descriptors. */
1171 		chan->seg_mv = dma_alloc_coherent(chan->dev,
1172 						  sizeof(*chan->seg_mv) *
1173 						  XILINX_DMA_NUM_DESCS,
1174 						  &chan->seg_p, GFP_KERNEL);
1175 		if (!chan->seg_mv) {
1176 			dev_err(chan->dev,
1177 				"unable to allocate channel %d descriptors\n",
1178 				chan->id);
1179 			return -ENOMEM;
1180 		}
1181 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1182 			chan->seg_mv[i].hw.next_desc =
1183 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1184 				((i + 1) % XILINX_DMA_NUM_DESCS));
1185 			chan->seg_mv[i].hw.next_desc_msb =
1186 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1187 				((i + 1) % XILINX_DMA_NUM_DESCS));
1188 			chan->seg_mv[i].phys = chan->seg_p +
1189 				sizeof(*chan->seg_mv) * i;
1190 			list_add_tail(&chan->seg_mv[i].node,
1191 				      &chan->free_seg_list);
1192 		}
1193 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1194 		chan->desc_pool = dma_pool_create("xilinx_cdma_desc_pool",
1195 				   chan->dev,
1196 				   sizeof(struct xilinx_cdma_tx_segment),
1197 				   __alignof__(struct xilinx_cdma_tx_segment),
1198 				   0);
1199 	} else {
1200 		chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
1201 				     chan->dev,
1202 				     sizeof(struct xilinx_vdma_tx_segment),
1203 				     __alignof__(struct xilinx_vdma_tx_segment),
1204 				     0);
1205 	}
1206 
1207 	if (!chan->desc_pool &&
1208 	    ((chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA) &&
1209 		chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA)) {
1210 		dev_err(chan->dev,
1211 			"unable to allocate channel %d descriptor pool\n",
1212 			chan->id);
1213 		return -ENOMEM;
1214 	}
1215 
1216 	dma_cookie_init(dchan);
1217 
1218 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1219 		/* For AXI DMA resetting once channel will reset the
1220 		 * other channel as well so enable the interrupts here.
1221 		 */
1222 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1223 			      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1224 	}
1225 
1226 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
1227 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1228 			     XILINX_CDMA_CR_SGMODE);
1229 
1230 	return 0;
1231 }
1232 
1233 /**
1234  * xilinx_dma_calc_copysize - Calculate the amount of data to copy
1235  * @chan: Driver specific DMA channel
1236  * @size: Total data that needs to be copied
1237  * @done: Amount of data that has been already copied
1238  *
1239  * Return: Amount of data that has to be copied
1240  */
1241 static int xilinx_dma_calc_copysize(struct xilinx_dma_chan *chan,
1242 				    int size, int done)
1243 {
1244 	size_t copy;
1245 
1246 	copy = min_t(size_t, size - done,
1247 		     chan->xdev->max_buffer_len);
1248 
1249 	if ((copy + done < size) &&
1250 	    chan->xdev->common.copy_align) {
1251 		/*
1252 		 * If this is not the last descriptor, make sure
1253 		 * the next one will be properly aligned
1254 		 */
1255 		copy = rounddown(copy,
1256 				 (1 << chan->xdev->common.copy_align));
1257 	}
1258 	return copy;
1259 }
1260 
1261 /**
1262  * xilinx_dma_tx_status - Get DMA transaction status
1263  * @dchan: DMA channel
1264  * @cookie: Transaction identifier
1265  * @txstate: Transaction state
1266  *
1267  * Return: DMA transaction status
1268  */
1269 static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
1270 					dma_cookie_t cookie,
1271 					struct dma_tx_state *txstate)
1272 {
1273 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1274 	struct xilinx_dma_tx_descriptor *desc;
1275 	enum dma_status ret;
1276 	unsigned long flags;
1277 	u32 residue = 0;
1278 
1279 	ret = dma_cookie_status(dchan, cookie, txstate);
1280 	if (ret == DMA_COMPLETE || !txstate)
1281 		return ret;
1282 
1283 	spin_lock_irqsave(&chan->lock, flags);
1284 	if (!list_empty(&chan->active_list)) {
1285 		desc = list_last_entry(&chan->active_list,
1286 				       struct xilinx_dma_tx_descriptor, node);
1287 		/*
1288 		 * VDMA and simple mode do not support residue reporting, so the
1289 		 * residue field will always be 0.
1290 		 */
1291 		if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA)
1292 			residue = xilinx_dma_get_residue(chan, desc);
1293 	}
1294 	spin_unlock_irqrestore(&chan->lock, flags);
1295 
1296 	dma_set_residue(txstate, residue);
1297 
1298 	return ret;
1299 }
1300 
1301 /**
1302  * xilinx_dma_stop_transfer - Halt DMA channel
1303  * @chan: Driver specific DMA channel
1304  *
1305  * Return: '0' on success and failure value on error
1306  */
1307 static int xilinx_dma_stop_transfer(struct xilinx_dma_chan *chan)
1308 {
1309 	u32 val;
1310 
1311 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1312 
1313 	/* Wait for the hardware to halt */
1314 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1315 				       val & XILINX_DMA_DMASR_HALTED, 0,
1316 				       XILINX_DMA_LOOP_COUNT);
1317 }
1318 
1319 /**
1320  * xilinx_cdma_stop_transfer - Wait for the current transfer to complete
1321  * @chan: Driver specific DMA channel
1322  *
1323  * Return: '0' on success and failure value on error
1324  */
1325 static int xilinx_cdma_stop_transfer(struct xilinx_dma_chan *chan)
1326 {
1327 	u32 val;
1328 
1329 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1330 				       val & XILINX_DMA_DMASR_IDLE, 0,
1331 				       XILINX_DMA_LOOP_COUNT);
1332 }
1333 
1334 /**
1335  * xilinx_dma_start - Start DMA channel
1336  * @chan: Driver specific DMA channel
1337  */
1338 static void xilinx_dma_start(struct xilinx_dma_chan *chan)
1339 {
1340 	int err;
1341 	u32 val;
1342 
1343 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1344 
1345 	/* Wait for the hardware to start */
1346 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1347 				      !(val & XILINX_DMA_DMASR_HALTED), 0,
1348 				      XILINX_DMA_LOOP_COUNT);
1349 
1350 	if (err) {
1351 		dev_err(chan->dev, "Cannot start channel %p: %x\n",
1352 			chan, dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1353 
1354 		chan->err = true;
1355 	}
1356 }
1357 
1358 /**
1359  * xilinx_vdma_start_transfer - Starts VDMA transfer
1360  * @chan: Driver specific channel struct pointer
1361  */
1362 static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
1363 {
1364 	struct xilinx_vdma_config *config = &chan->config;
1365 	struct xilinx_dma_tx_descriptor *desc;
1366 	u32 reg, j;
1367 	struct xilinx_vdma_tx_segment *segment, *last = NULL;
1368 	int i = 0;
1369 
1370 	/* This function was invoked with lock held */
1371 	if (chan->err)
1372 		return;
1373 
1374 	if (!chan->idle)
1375 		return;
1376 
1377 	if (list_empty(&chan->pending_list))
1378 		return;
1379 
1380 	desc = list_first_entry(&chan->pending_list,
1381 				struct xilinx_dma_tx_descriptor, node);
1382 
1383 	/* Configure the hardware using info in the config structure */
1384 	if (chan->has_vflip) {
1385 		reg = dma_read(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP);
1386 		reg &= ~XILINX_VDMA_ENABLE_VERTICAL_FLIP;
1387 		reg |= config->vflip_en;
1388 		dma_write(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP,
1389 			  reg);
1390 	}
1391 
1392 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1393 
1394 	if (config->frm_cnt_en)
1395 		reg |= XILINX_DMA_DMACR_FRAMECNT_EN;
1396 	else
1397 		reg &= ~XILINX_DMA_DMACR_FRAMECNT_EN;
1398 
1399 	/* If not parking, enable circular mode */
1400 	if (config->park)
1401 		reg &= ~XILINX_DMA_DMACR_CIRC_EN;
1402 	else
1403 		reg |= XILINX_DMA_DMACR_CIRC_EN;
1404 
1405 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1406 
1407 	j = chan->desc_submitcount;
1408 	reg = dma_read(chan, XILINX_DMA_REG_PARK_PTR);
1409 	if (chan->direction == DMA_MEM_TO_DEV) {
1410 		reg &= ~XILINX_DMA_PARK_PTR_RD_REF_MASK;
1411 		reg |= j << XILINX_DMA_PARK_PTR_RD_REF_SHIFT;
1412 	} else {
1413 		reg &= ~XILINX_DMA_PARK_PTR_WR_REF_MASK;
1414 		reg |= j << XILINX_DMA_PARK_PTR_WR_REF_SHIFT;
1415 	}
1416 	dma_write(chan, XILINX_DMA_REG_PARK_PTR, reg);
1417 
1418 	/* Start the hardware */
1419 	xilinx_dma_start(chan);
1420 
1421 	if (chan->err)
1422 		return;
1423 
1424 	/* Start the transfer */
1425 	if (chan->desc_submitcount < chan->num_frms)
1426 		i = chan->desc_submitcount;
1427 
1428 	list_for_each_entry(segment, &desc->segments, node) {
1429 		if (chan->ext_addr)
1430 			vdma_desc_write_64(chan,
1431 				   XILINX_VDMA_REG_START_ADDRESS_64(i++),
1432 				   segment->hw.buf_addr,
1433 				   segment->hw.buf_addr_msb);
1434 		else
1435 			vdma_desc_write(chan,
1436 					XILINX_VDMA_REG_START_ADDRESS(i++),
1437 					segment->hw.buf_addr);
1438 
1439 		last = segment;
1440 	}
1441 
1442 	if (!last)
1443 		return;
1444 
1445 	/* HW expects these parameters to be same for one transaction */
1446 	vdma_desc_write(chan, XILINX_DMA_REG_HSIZE, last->hw.hsize);
1447 	vdma_desc_write(chan, XILINX_DMA_REG_FRMDLY_STRIDE,
1448 			last->hw.stride);
1449 	vdma_desc_write(chan, XILINX_DMA_REG_VSIZE, last->hw.vsize);
1450 
1451 	chan->desc_submitcount++;
1452 	chan->desc_pendingcount--;
1453 	list_move_tail(&desc->node, &chan->active_list);
1454 	if (chan->desc_submitcount == chan->num_frms)
1455 		chan->desc_submitcount = 0;
1456 
1457 	chan->idle = false;
1458 }
1459 
1460 /**
1461  * xilinx_cdma_start_transfer - Starts cdma transfer
1462  * @chan: Driver specific channel struct pointer
1463  */
1464 static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
1465 {
1466 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1467 	struct xilinx_cdma_tx_segment *tail_segment;
1468 	u32 ctrl_reg = dma_read(chan, XILINX_DMA_REG_DMACR);
1469 
1470 	if (chan->err)
1471 		return;
1472 
1473 	if (!chan->idle)
1474 		return;
1475 
1476 	if (list_empty(&chan->pending_list))
1477 		return;
1478 
1479 	head_desc = list_first_entry(&chan->pending_list,
1480 				     struct xilinx_dma_tx_descriptor, node);
1481 	tail_desc = list_last_entry(&chan->pending_list,
1482 				    struct xilinx_dma_tx_descriptor, node);
1483 	tail_segment = list_last_entry(&tail_desc->segments,
1484 				       struct xilinx_cdma_tx_segment, node);
1485 
1486 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1487 		ctrl_reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1488 		ctrl_reg |= chan->desc_pendingcount <<
1489 				XILINX_DMA_CR_COALESCE_SHIFT;
1490 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, ctrl_reg);
1491 	}
1492 
1493 	if (chan->has_sg) {
1494 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
1495 			     XILINX_CDMA_CR_SGMODE);
1496 
1497 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1498 			     XILINX_CDMA_CR_SGMODE);
1499 
1500 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1501 			     head_desc->async_tx.phys);
1502 
1503 		/* Update tail ptr register which will start the transfer */
1504 		xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1505 			     tail_segment->phys);
1506 	} else {
1507 		/* In simple mode */
1508 		struct xilinx_cdma_tx_segment *segment;
1509 		struct xilinx_cdma_desc_hw *hw;
1510 
1511 		segment = list_first_entry(&head_desc->segments,
1512 					   struct xilinx_cdma_tx_segment,
1513 					   node);
1514 
1515 		hw = &segment->hw;
1516 
1517 		xilinx_write(chan, XILINX_CDMA_REG_SRCADDR,
1518 			     xilinx_prep_dma_addr_t(hw->src_addr));
1519 		xilinx_write(chan, XILINX_CDMA_REG_DSTADDR,
1520 			     xilinx_prep_dma_addr_t(hw->dest_addr));
1521 
1522 		/* Start the transfer */
1523 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1524 				hw->control & chan->xdev->max_buffer_len);
1525 	}
1526 
1527 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1528 	chan->desc_pendingcount = 0;
1529 	chan->idle = false;
1530 }
1531 
1532 /**
1533  * xilinx_dma_start_transfer - Starts DMA transfer
1534  * @chan: Driver specific channel struct pointer
1535  */
1536 static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
1537 {
1538 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1539 	struct xilinx_axidma_tx_segment *tail_segment;
1540 	u32 reg;
1541 
1542 	if (chan->err)
1543 		return;
1544 
1545 	if (list_empty(&chan->pending_list))
1546 		return;
1547 
1548 	if (!chan->idle)
1549 		return;
1550 
1551 	head_desc = list_first_entry(&chan->pending_list,
1552 				     struct xilinx_dma_tx_descriptor, node);
1553 	tail_desc = list_last_entry(&chan->pending_list,
1554 				    struct xilinx_dma_tx_descriptor, node);
1555 	tail_segment = list_last_entry(&tail_desc->segments,
1556 				       struct xilinx_axidma_tx_segment, node);
1557 
1558 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1559 
1560 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1561 		reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1562 		reg |= chan->desc_pendingcount <<
1563 				  XILINX_DMA_CR_COALESCE_SHIFT;
1564 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1565 	}
1566 
1567 	if (chan->has_sg)
1568 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1569 			     head_desc->async_tx.phys);
1570 	reg  &= ~XILINX_DMA_CR_DELAY_MAX;
1571 	reg  |= chan->irq_delay << XILINX_DMA_CR_DELAY_SHIFT;
1572 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1573 
1574 	xilinx_dma_start(chan);
1575 
1576 	if (chan->err)
1577 		return;
1578 
1579 	/* Start the transfer */
1580 	if (chan->has_sg) {
1581 		if (chan->cyclic)
1582 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1583 				     chan->cyclic_seg_v->phys);
1584 		else
1585 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1586 				     tail_segment->phys);
1587 	} else {
1588 		struct xilinx_axidma_tx_segment *segment;
1589 		struct xilinx_axidma_desc_hw *hw;
1590 
1591 		segment = list_first_entry(&head_desc->segments,
1592 					   struct xilinx_axidma_tx_segment,
1593 					   node);
1594 		hw = &segment->hw;
1595 
1596 		xilinx_write(chan, XILINX_DMA_REG_SRCDSTADDR,
1597 			     xilinx_prep_dma_addr_t(hw->buf_addr));
1598 
1599 		/* Start the transfer */
1600 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1601 			       hw->control & chan->xdev->max_buffer_len);
1602 	}
1603 
1604 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1605 	chan->desc_pendingcount = 0;
1606 	chan->idle = false;
1607 }
1608 
1609 /**
1610  * xilinx_mcdma_start_transfer - Starts MCDMA transfer
1611  * @chan: Driver specific channel struct pointer
1612  */
1613 static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan)
1614 {
1615 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1616 	struct xilinx_aximcdma_tx_segment *tail_segment;
1617 	u32 reg;
1618 
1619 	/*
1620 	 * lock has been held by calling functions, so we don't need it
1621 	 * to take it here again.
1622 	 */
1623 
1624 	if (chan->err)
1625 		return;
1626 
1627 	if (!chan->idle)
1628 		return;
1629 
1630 	if (list_empty(&chan->pending_list))
1631 		return;
1632 
1633 	head_desc = list_first_entry(&chan->pending_list,
1634 				     struct xilinx_dma_tx_descriptor, node);
1635 	tail_desc = list_last_entry(&chan->pending_list,
1636 				    struct xilinx_dma_tx_descriptor, node);
1637 	tail_segment = list_last_entry(&tail_desc->segments,
1638 				       struct xilinx_aximcdma_tx_segment, node);
1639 
1640 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1641 
1642 	if (chan->desc_pendingcount <= XILINX_MCDMA_COALESCE_MAX) {
1643 		reg &= ~XILINX_MCDMA_COALESCE_MASK;
1644 		reg |= chan->desc_pendingcount <<
1645 			XILINX_MCDMA_COALESCE_SHIFT;
1646 	}
1647 
1648 	reg |= XILINX_MCDMA_IRQ_ALL_MASK;
1649 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1650 
1651 	/* Program current descriptor */
1652 	xilinx_write(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET(chan->tdest),
1653 		     head_desc->async_tx.phys);
1654 
1655 	/* Program channel enable register */
1656 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHEN_OFFSET);
1657 	reg |= BIT(chan->tdest);
1658 	dma_ctrl_write(chan, XILINX_MCDMA_CHEN_OFFSET, reg);
1659 
1660 	/* Start the fetch of BDs for the channel */
1661 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1662 	reg |= XILINX_MCDMA_CR_RUNSTOP_MASK;
1663 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1664 
1665 	xilinx_dma_start(chan);
1666 
1667 	if (chan->err)
1668 		return;
1669 
1670 	/* Start the transfer */
1671 	xilinx_write(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET(chan->tdest),
1672 		     tail_segment->phys);
1673 
1674 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1675 	chan->desc_pendingcount = 0;
1676 	chan->idle = false;
1677 }
1678 
1679 /**
1680  * xilinx_dma_issue_pending - Issue pending transactions
1681  * @dchan: DMA channel
1682  */
1683 static void xilinx_dma_issue_pending(struct dma_chan *dchan)
1684 {
1685 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1686 	unsigned long flags;
1687 
1688 	spin_lock_irqsave(&chan->lock, flags);
1689 	chan->start_transfer(chan);
1690 	spin_unlock_irqrestore(&chan->lock, flags);
1691 }
1692 
1693 /**
1694  * xilinx_dma_device_config - Configure the DMA channel
1695  * @dchan: DMA channel
1696  * @config: channel configuration
1697  *
1698  * Return: 0 always.
1699  */
1700 static int xilinx_dma_device_config(struct dma_chan *dchan,
1701 				    struct dma_slave_config *config)
1702 {
1703 	return 0;
1704 }
1705 
1706 /**
1707  * xilinx_dma_complete_descriptor - Mark the active descriptor as complete
1708  * @chan : xilinx DMA channel
1709  *
1710  * CONTEXT: hardirq
1711  */
1712 static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
1713 {
1714 	struct xilinx_dma_tx_descriptor *desc, *next;
1715 
1716 	/* This function was invoked with lock held */
1717 	if (list_empty(&chan->active_list))
1718 		return;
1719 
1720 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
1721 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1722 			struct xilinx_axidma_tx_segment *seg;
1723 
1724 			seg = list_last_entry(&desc->segments,
1725 					      struct xilinx_axidma_tx_segment, node);
1726 			if (!(seg->hw.status & XILINX_DMA_BD_COMP_MASK) && chan->has_sg)
1727 				break;
1728 		}
1729 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
1730 		    XDMA_TYPE_VDMA)
1731 			desc->residue = xilinx_dma_get_residue(chan, desc);
1732 		else
1733 			desc->residue = 0;
1734 		desc->err = chan->err;
1735 
1736 		list_del(&desc->node);
1737 		if (!desc->cyclic)
1738 			dma_cookie_complete(&desc->async_tx);
1739 		list_add_tail(&desc->node, &chan->done_list);
1740 	}
1741 }
1742 
1743 /**
1744  * xilinx_dma_reset - Reset DMA channel
1745  * @chan: Driver specific DMA channel
1746  *
1747  * Return: '0' on success and failure value on error
1748  */
1749 static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
1750 {
1751 	int err;
1752 	u32 tmp;
1753 
1754 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RESET);
1755 
1756 	/* Wait for the hardware to finish reset */
1757 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMACR, tmp,
1758 				      !(tmp & XILINX_DMA_DMACR_RESET), 0,
1759 				      XILINX_DMA_LOOP_COUNT);
1760 
1761 	if (err) {
1762 		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
1763 			dma_ctrl_read(chan, XILINX_DMA_REG_DMACR),
1764 			dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1765 		return -ETIMEDOUT;
1766 	}
1767 
1768 	chan->err = false;
1769 	chan->idle = true;
1770 	chan->desc_pendingcount = 0;
1771 	chan->desc_submitcount = 0;
1772 
1773 	return err;
1774 }
1775 
1776 /**
1777  * xilinx_dma_chan_reset - Reset DMA channel and enable interrupts
1778  * @chan: Driver specific DMA channel
1779  *
1780  * Return: '0' on success and failure value on error
1781  */
1782 static int xilinx_dma_chan_reset(struct xilinx_dma_chan *chan)
1783 {
1784 	int err;
1785 
1786 	/* Reset VDMA */
1787 	err = xilinx_dma_reset(chan);
1788 	if (err)
1789 		return err;
1790 
1791 	/* Enable interrupts */
1792 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1793 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1794 
1795 	return 0;
1796 }
1797 
1798 /**
1799  * xilinx_mcdma_irq_handler - MCDMA Interrupt handler
1800  * @irq: IRQ number
1801  * @data: Pointer to the Xilinx MCDMA channel structure
1802  *
1803  * Return: IRQ_HANDLED/IRQ_NONE
1804  */
1805 static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
1806 {
1807 	struct xilinx_dma_chan *chan = data;
1808 	u32 status, ser_offset, chan_sermask, chan_offset = 0, chan_id;
1809 
1810 	if (chan->direction == DMA_DEV_TO_MEM)
1811 		ser_offset = XILINX_MCDMA_RXINT_SER_OFFSET;
1812 	else
1813 		ser_offset = XILINX_MCDMA_TXINT_SER_OFFSET;
1814 
1815 	/* Read the channel id raising the interrupt*/
1816 	chan_sermask = dma_ctrl_read(chan, ser_offset);
1817 	chan_id = ffs(chan_sermask);
1818 
1819 	if (!chan_id)
1820 		return IRQ_NONE;
1821 
1822 	if (chan->direction == DMA_DEV_TO_MEM)
1823 		chan_offset = chan->xdev->dma_config->max_channels / 2;
1824 
1825 	chan_offset = chan_offset + (chan_id - 1);
1826 	chan = chan->xdev->chan[chan_offset];
1827 	/* Read the status and ack the interrupts. */
1828 	status = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest));
1829 	if (!(status & XILINX_MCDMA_IRQ_ALL_MASK))
1830 		return IRQ_NONE;
1831 
1832 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest),
1833 		       status & XILINX_MCDMA_IRQ_ALL_MASK);
1834 
1835 	if (status & XILINX_MCDMA_IRQ_ERR_MASK) {
1836 		dev_err(chan->dev, "Channel %p has errors %x cdr %x tdr %x\n",
1837 			chan,
1838 			dma_ctrl_read(chan, XILINX_MCDMA_CH_ERR_OFFSET),
1839 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET
1840 				      (chan->tdest)),
1841 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET
1842 				      (chan->tdest)));
1843 		chan->err = true;
1844 	}
1845 
1846 	if (status & XILINX_MCDMA_IRQ_DELAY_MASK) {
1847 		/*
1848 		 * Device takes too long to do the transfer when user requires
1849 		 * responsiveness.
1850 		 */
1851 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1852 	}
1853 
1854 	if (status & XILINX_MCDMA_IRQ_IOC_MASK) {
1855 		spin_lock(&chan->lock);
1856 		xilinx_dma_complete_descriptor(chan);
1857 		chan->idle = true;
1858 		chan->start_transfer(chan);
1859 		spin_unlock(&chan->lock);
1860 	}
1861 
1862 	tasklet_hi_schedule(&chan->tasklet);
1863 	return IRQ_HANDLED;
1864 }
1865 
1866 /**
1867  * xilinx_dma_irq_handler - DMA Interrupt handler
1868  * @irq: IRQ number
1869  * @data: Pointer to the Xilinx DMA channel structure
1870  *
1871  * Return: IRQ_HANDLED/IRQ_NONE
1872  */
1873 static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
1874 {
1875 	struct xilinx_dma_chan *chan = data;
1876 	u32 status;
1877 
1878 	/* Read the status and ack the interrupts. */
1879 	status = dma_ctrl_read(chan, XILINX_DMA_REG_DMASR);
1880 	if (!(status & XILINX_DMA_DMAXR_ALL_IRQ_MASK))
1881 		return IRQ_NONE;
1882 
1883 	dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1884 			status & XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1885 
1886 	if (status & XILINX_DMA_DMASR_ERR_IRQ) {
1887 		/*
1888 		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
1889 		 * error is recoverable, ignore it. Otherwise flag the error.
1890 		 *
1891 		 * Only recoverable errors can be cleared in the DMASR register,
1892 		 * make sure not to write to other error bits to 1.
1893 		 */
1894 		u32 errors = status & XILINX_DMA_DMASR_ALL_ERR_MASK;
1895 
1896 		dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1897 				errors & XILINX_DMA_DMASR_ERR_RECOVER_MASK);
1898 
1899 		if (!chan->flush_on_fsync ||
1900 		    (errors & ~XILINX_DMA_DMASR_ERR_RECOVER_MASK)) {
1901 			dev_err(chan->dev,
1902 				"Channel %p has errors %x, cdr %x tdr %x\n",
1903 				chan, errors,
1904 				dma_ctrl_read(chan, XILINX_DMA_REG_CURDESC),
1905 				dma_ctrl_read(chan, XILINX_DMA_REG_TAILDESC));
1906 			chan->err = true;
1907 		}
1908 	}
1909 
1910 	if (status & (XILINX_DMA_DMASR_FRM_CNT_IRQ |
1911 		      XILINX_DMA_DMASR_DLY_CNT_IRQ)) {
1912 		spin_lock(&chan->lock);
1913 		xilinx_dma_complete_descriptor(chan);
1914 		chan->idle = true;
1915 		chan->start_transfer(chan);
1916 		spin_unlock(&chan->lock);
1917 	}
1918 
1919 	tasklet_schedule(&chan->tasklet);
1920 	return IRQ_HANDLED;
1921 }
1922 
1923 /**
1924  * append_desc_queue - Queuing descriptor
1925  * @chan: Driver specific dma channel
1926  * @desc: dma transaction descriptor
1927  */
1928 static void append_desc_queue(struct xilinx_dma_chan *chan,
1929 			      struct xilinx_dma_tx_descriptor *desc)
1930 {
1931 	struct xilinx_vdma_tx_segment *tail_segment;
1932 	struct xilinx_dma_tx_descriptor *tail_desc;
1933 	struct xilinx_axidma_tx_segment *axidma_tail_segment;
1934 	struct xilinx_aximcdma_tx_segment *aximcdma_tail_segment;
1935 	struct xilinx_cdma_tx_segment *cdma_tail_segment;
1936 
1937 	if (list_empty(&chan->pending_list))
1938 		goto append;
1939 
1940 	/*
1941 	 * Add the hardware descriptor to the chain of hardware descriptors
1942 	 * that already exists in memory.
1943 	 */
1944 	tail_desc = list_last_entry(&chan->pending_list,
1945 				    struct xilinx_dma_tx_descriptor, node);
1946 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
1947 		tail_segment = list_last_entry(&tail_desc->segments,
1948 					       struct xilinx_vdma_tx_segment,
1949 					       node);
1950 		tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1951 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1952 		cdma_tail_segment = list_last_entry(&tail_desc->segments,
1953 						struct xilinx_cdma_tx_segment,
1954 						node);
1955 		cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1956 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1957 		axidma_tail_segment = list_last_entry(&tail_desc->segments,
1958 					       struct xilinx_axidma_tx_segment,
1959 					       node);
1960 		axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1961 	} else {
1962 		aximcdma_tail_segment =
1963 			list_last_entry(&tail_desc->segments,
1964 					struct xilinx_aximcdma_tx_segment,
1965 					node);
1966 		aximcdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1967 	}
1968 
1969 	/*
1970 	 * Add the software descriptor and all children to the list
1971 	 * of pending transactions
1972 	 */
1973 append:
1974 	list_add_tail(&desc->node, &chan->pending_list);
1975 	chan->desc_pendingcount++;
1976 
1977 	if (chan->has_sg && (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA)
1978 	    && unlikely(chan->desc_pendingcount > chan->num_frms)) {
1979 		dev_dbg(chan->dev, "desc pendingcount is too high\n");
1980 		chan->desc_pendingcount = chan->num_frms;
1981 	}
1982 }
1983 
1984 /**
1985  * xilinx_dma_tx_submit - Submit DMA transaction
1986  * @tx: Async transaction descriptor
1987  *
1988  * Return: cookie value on success and failure value on error
1989  */
1990 static dma_cookie_t xilinx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
1991 {
1992 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
1993 	struct xilinx_dma_chan *chan = to_xilinx_chan(tx->chan);
1994 	dma_cookie_t cookie;
1995 	unsigned long flags;
1996 	int err;
1997 
1998 	if (chan->cyclic) {
1999 		xilinx_dma_free_tx_descriptor(chan, desc);
2000 		return -EBUSY;
2001 	}
2002 
2003 	if (chan->err) {
2004 		/*
2005 		 * If reset fails, need to hard reset the system.
2006 		 * Channel is no longer functional
2007 		 */
2008 		err = xilinx_dma_chan_reset(chan);
2009 		if (err < 0)
2010 			return err;
2011 	}
2012 
2013 	spin_lock_irqsave(&chan->lock, flags);
2014 
2015 	cookie = dma_cookie_assign(tx);
2016 
2017 	/* Put this transaction onto the tail of the pending queue */
2018 	append_desc_queue(chan, desc);
2019 
2020 	if (desc->cyclic)
2021 		chan->cyclic = true;
2022 
2023 	chan->terminating = false;
2024 
2025 	spin_unlock_irqrestore(&chan->lock, flags);
2026 
2027 	return cookie;
2028 }
2029 
2030 /**
2031  * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
2032  *	DMA_SLAVE transaction
2033  * @dchan: DMA channel
2034  * @xt: Interleaved template pointer
2035  * @flags: transfer ack flags
2036  *
2037  * Return: Async transaction descriptor on success and NULL on failure
2038  */
2039 static struct dma_async_tx_descriptor *
2040 xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
2041 				 struct dma_interleaved_template *xt,
2042 				 unsigned long flags)
2043 {
2044 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2045 	struct xilinx_dma_tx_descriptor *desc;
2046 	struct xilinx_vdma_tx_segment *segment;
2047 	struct xilinx_vdma_desc_hw *hw;
2048 
2049 	if (!is_slave_direction(xt->dir))
2050 		return NULL;
2051 
2052 	if (!xt->numf || !xt->sgl[0].size)
2053 		return NULL;
2054 
2055 	if (xt->numf & ~XILINX_DMA_VSIZE_MASK ||
2056 	    xt->sgl[0].size & ~XILINX_DMA_HSIZE_MASK)
2057 		return NULL;
2058 
2059 	if (xt->frame_size != 1)
2060 		return NULL;
2061 
2062 	/* Allocate a transaction descriptor. */
2063 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2064 	if (!desc)
2065 		return NULL;
2066 
2067 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2068 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2069 	async_tx_ack(&desc->async_tx);
2070 
2071 	/* Allocate the link descriptor from DMA pool */
2072 	segment = xilinx_vdma_alloc_tx_segment(chan);
2073 	if (!segment)
2074 		goto error;
2075 
2076 	/* Fill in the hardware descriptor */
2077 	hw = &segment->hw;
2078 	hw->vsize = xt->numf;
2079 	hw->hsize = xt->sgl[0].size;
2080 	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
2081 			XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT;
2082 	hw->stride |= chan->config.frm_dly <<
2083 			XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
2084 
2085 	if (xt->dir != DMA_MEM_TO_DEV) {
2086 		if (chan->ext_addr) {
2087 			hw->buf_addr = lower_32_bits(xt->dst_start);
2088 			hw->buf_addr_msb = upper_32_bits(xt->dst_start);
2089 		} else {
2090 			hw->buf_addr = xt->dst_start;
2091 		}
2092 	} else {
2093 		if (chan->ext_addr) {
2094 			hw->buf_addr = lower_32_bits(xt->src_start);
2095 			hw->buf_addr_msb = upper_32_bits(xt->src_start);
2096 		} else {
2097 			hw->buf_addr = xt->src_start;
2098 		}
2099 	}
2100 
2101 	/* Insert the segment into the descriptor segments list. */
2102 	list_add_tail(&segment->node, &desc->segments);
2103 
2104 	/* Link the last hardware descriptor with the first. */
2105 	segment = list_first_entry(&desc->segments,
2106 				   struct xilinx_vdma_tx_segment, node);
2107 	desc->async_tx.phys = segment->phys;
2108 
2109 	return &desc->async_tx;
2110 
2111 error:
2112 	xilinx_dma_free_tx_descriptor(chan, desc);
2113 	return NULL;
2114 }
2115 
2116 /**
2117  * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
2118  * @dchan: DMA channel
2119  * @dma_dst: destination address
2120  * @dma_src: source address
2121  * @len: transfer length
2122  * @flags: transfer ack flags
2123  *
2124  * Return: Async transaction descriptor on success and NULL on failure
2125  */
2126 static struct dma_async_tx_descriptor *
2127 xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
2128 			dma_addr_t dma_src, size_t len, unsigned long flags)
2129 {
2130 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2131 	struct xilinx_dma_tx_descriptor *desc;
2132 	struct xilinx_cdma_tx_segment *segment;
2133 	struct xilinx_cdma_desc_hw *hw;
2134 
2135 	if (!len || len > chan->xdev->max_buffer_len)
2136 		return NULL;
2137 
2138 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2139 	if (!desc)
2140 		return NULL;
2141 
2142 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2143 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2144 
2145 	/* Allocate the link descriptor from DMA pool */
2146 	segment = xilinx_cdma_alloc_tx_segment(chan);
2147 	if (!segment)
2148 		goto error;
2149 
2150 	hw = &segment->hw;
2151 	hw->control = len;
2152 	hw->src_addr = dma_src;
2153 	hw->dest_addr = dma_dst;
2154 	if (chan->ext_addr) {
2155 		hw->src_addr_msb = upper_32_bits(dma_src);
2156 		hw->dest_addr_msb = upper_32_bits(dma_dst);
2157 	}
2158 
2159 	/* Insert the segment into the descriptor segments list. */
2160 	list_add_tail(&segment->node, &desc->segments);
2161 
2162 	desc->async_tx.phys = segment->phys;
2163 	hw->next_desc = segment->phys;
2164 
2165 	return &desc->async_tx;
2166 
2167 error:
2168 	xilinx_dma_free_tx_descriptor(chan, desc);
2169 	return NULL;
2170 }
2171 
2172 /**
2173  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2174  * @dchan: DMA channel
2175  * @sgl: scatterlist to transfer to/from
2176  * @sg_len: number of entries in @scatterlist
2177  * @direction: DMA direction
2178  * @flags: transfer ack flags
2179  * @context: APP words of the descriptor
2180  *
2181  * Return: Async transaction descriptor on success and NULL on failure
2182  */
2183 static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
2184 	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
2185 	enum dma_transfer_direction direction, unsigned long flags,
2186 	void *context)
2187 {
2188 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2189 	struct xilinx_dma_tx_descriptor *desc;
2190 	struct xilinx_axidma_tx_segment *segment = NULL;
2191 	u32 *app_w = (u32 *)context;
2192 	struct scatterlist *sg;
2193 	size_t copy;
2194 	size_t sg_used;
2195 	unsigned int i;
2196 
2197 	if (!is_slave_direction(direction))
2198 		return NULL;
2199 
2200 	/* Allocate a transaction descriptor. */
2201 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2202 	if (!desc)
2203 		return NULL;
2204 
2205 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2206 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2207 
2208 	/* Build transactions using information in the scatter gather list */
2209 	for_each_sg(sgl, sg, sg_len, i) {
2210 		sg_used = 0;
2211 
2212 		/* Loop until the entire scatterlist entry is used */
2213 		while (sg_used < sg_dma_len(sg)) {
2214 			struct xilinx_axidma_desc_hw *hw;
2215 
2216 			/* Get a free segment */
2217 			segment = xilinx_axidma_alloc_tx_segment(chan);
2218 			if (!segment)
2219 				goto error;
2220 
2221 			/*
2222 			 * Calculate the maximum number of bytes to transfer,
2223 			 * making sure it is less than the hw limit
2224 			 */
2225 			copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
2226 							sg_used);
2227 			hw = &segment->hw;
2228 
2229 			/* Fill in the descriptor */
2230 			xilinx_axidma_buf(chan, hw, sg_dma_address(sg),
2231 					  sg_used, 0);
2232 
2233 			hw->control = copy;
2234 
2235 			if (chan->direction == DMA_MEM_TO_DEV) {
2236 				if (app_w)
2237 					memcpy(hw->app, app_w, sizeof(u32) *
2238 					       XILINX_DMA_NUM_APP_WORDS);
2239 			}
2240 
2241 			sg_used += copy;
2242 
2243 			/*
2244 			 * Insert the segment into the descriptor segments
2245 			 * list.
2246 			 */
2247 			list_add_tail(&segment->node, &desc->segments);
2248 		}
2249 	}
2250 
2251 	segment = list_first_entry(&desc->segments,
2252 				   struct xilinx_axidma_tx_segment, node);
2253 	desc->async_tx.phys = segment->phys;
2254 
2255 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2256 	if (chan->direction == DMA_MEM_TO_DEV) {
2257 		segment->hw.control |= XILINX_DMA_BD_SOP;
2258 		segment = list_last_entry(&desc->segments,
2259 					  struct xilinx_axidma_tx_segment,
2260 					  node);
2261 		segment->hw.control |= XILINX_DMA_BD_EOP;
2262 	}
2263 
2264 	if (chan->xdev->has_axistream_connected)
2265 		desc->async_tx.metadata_ops = &xilinx_dma_metadata_ops;
2266 
2267 	return &desc->async_tx;
2268 
2269 error:
2270 	xilinx_dma_free_tx_descriptor(chan, desc);
2271 	return NULL;
2272 }
2273 
2274 /**
2275  * xilinx_dma_prep_dma_cyclic - prepare descriptors for a DMA_SLAVE transaction
2276  * @dchan: DMA channel
2277  * @buf_addr: Physical address of the buffer
2278  * @buf_len: Total length of the cyclic buffers
2279  * @period_len: length of individual cyclic buffer
2280  * @direction: DMA direction
2281  * @flags: transfer ack flags
2282  *
2283  * Return: Async transaction descriptor on success and NULL on failure
2284  */
2285 static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
2286 	struct dma_chan *dchan, dma_addr_t buf_addr, size_t buf_len,
2287 	size_t period_len, enum dma_transfer_direction direction,
2288 	unsigned long flags)
2289 {
2290 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2291 	struct xilinx_dma_tx_descriptor *desc;
2292 	struct xilinx_axidma_tx_segment *segment, *head_segment, *prev = NULL;
2293 	size_t copy, sg_used;
2294 	unsigned int num_periods;
2295 	int i;
2296 	u32 reg;
2297 
2298 	if (!period_len)
2299 		return NULL;
2300 
2301 	num_periods = buf_len / period_len;
2302 
2303 	if (!num_periods)
2304 		return NULL;
2305 
2306 	if (!is_slave_direction(direction))
2307 		return NULL;
2308 
2309 	/* Allocate a transaction descriptor. */
2310 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2311 	if (!desc)
2312 		return NULL;
2313 
2314 	chan->direction = direction;
2315 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2316 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2317 
2318 	for (i = 0; i < num_periods; ++i) {
2319 		sg_used = 0;
2320 
2321 		while (sg_used < period_len) {
2322 			struct xilinx_axidma_desc_hw *hw;
2323 
2324 			/* Get a free segment */
2325 			segment = xilinx_axidma_alloc_tx_segment(chan);
2326 			if (!segment)
2327 				goto error;
2328 
2329 			/*
2330 			 * Calculate the maximum number of bytes to transfer,
2331 			 * making sure it is less than the hw limit
2332 			 */
2333 			copy = xilinx_dma_calc_copysize(chan, period_len,
2334 							sg_used);
2335 			hw = &segment->hw;
2336 			xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
2337 					  period_len * i);
2338 			hw->control = copy;
2339 
2340 			if (prev)
2341 				prev->hw.next_desc = segment->phys;
2342 
2343 			prev = segment;
2344 			sg_used += copy;
2345 
2346 			/*
2347 			 * Insert the segment into the descriptor segments
2348 			 * list.
2349 			 */
2350 			list_add_tail(&segment->node, &desc->segments);
2351 		}
2352 	}
2353 
2354 	head_segment = list_first_entry(&desc->segments,
2355 				   struct xilinx_axidma_tx_segment, node);
2356 	desc->async_tx.phys = head_segment->phys;
2357 
2358 	desc->cyclic = true;
2359 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2360 	reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2361 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2362 
2363 	segment = list_last_entry(&desc->segments,
2364 				  struct xilinx_axidma_tx_segment,
2365 				  node);
2366 	segment->hw.next_desc = (u32) head_segment->phys;
2367 
2368 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2369 	if (direction == DMA_MEM_TO_DEV) {
2370 		head_segment->hw.control |= XILINX_DMA_BD_SOP;
2371 		segment->hw.control |= XILINX_DMA_BD_EOP;
2372 	}
2373 
2374 	return &desc->async_tx;
2375 
2376 error:
2377 	xilinx_dma_free_tx_descriptor(chan, desc);
2378 	return NULL;
2379 }
2380 
2381 /**
2382  * xilinx_mcdma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2383  * @dchan: DMA channel
2384  * @sgl: scatterlist to transfer to/from
2385  * @sg_len: number of entries in @scatterlist
2386  * @direction: DMA direction
2387  * @flags: transfer ack flags
2388  * @context: APP words of the descriptor
2389  *
2390  * Return: Async transaction descriptor on success and NULL on failure
2391  */
2392 static struct dma_async_tx_descriptor *
2393 xilinx_mcdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
2394 			   unsigned int sg_len,
2395 			   enum dma_transfer_direction direction,
2396 			   unsigned long flags, void *context)
2397 {
2398 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2399 	struct xilinx_dma_tx_descriptor *desc;
2400 	struct xilinx_aximcdma_tx_segment *segment = NULL;
2401 	u32 *app_w = (u32 *)context;
2402 	struct scatterlist *sg;
2403 	size_t copy;
2404 	size_t sg_used;
2405 	unsigned int i;
2406 
2407 	if (!is_slave_direction(direction))
2408 		return NULL;
2409 
2410 	/* Allocate a transaction descriptor. */
2411 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2412 	if (!desc)
2413 		return NULL;
2414 
2415 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2416 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2417 
2418 	/* Build transactions using information in the scatter gather list */
2419 	for_each_sg(sgl, sg, sg_len, i) {
2420 		sg_used = 0;
2421 
2422 		/* Loop until the entire scatterlist entry is used */
2423 		while (sg_used < sg_dma_len(sg)) {
2424 			struct xilinx_aximcdma_desc_hw *hw;
2425 
2426 			/* Get a free segment */
2427 			segment = xilinx_aximcdma_alloc_tx_segment(chan);
2428 			if (!segment)
2429 				goto error;
2430 
2431 			/*
2432 			 * Calculate the maximum number of bytes to transfer,
2433 			 * making sure it is less than the hw limit
2434 			 */
2435 			copy = min_t(size_t, sg_dma_len(sg) - sg_used,
2436 				     chan->xdev->max_buffer_len);
2437 			hw = &segment->hw;
2438 
2439 			/* Fill in the descriptor */
2440 			xilinx_aximcdma_buf(chan, hw, sg_dma_address(sg),
2441 					    sg_used);
2442 			hw->control = copy;
2443 
2444 			if (chan->direction == DMA_MEM_TO_DEV && app_w) {
2445 				memcpy(hw->app, app_w, sizeof(u32) *
2446 				       XILINX_DMA_NUM_APP_WORDS);
2447 			}
2448 
2449 			sg_used += copy;
2450 			/*
2451 			 * Insert the segment into the descriptor segments
2452 			 * list.
2453 			 */
2454 			list_add_tail(&segment->node, &desc->segments);
2455 		}
2456 	}
2457 
2458 	segment = list_first_entry(&desc->segments,
2459 				   struct xilinx_aximcdma_tx_segment, node);
2460 	desc->async_tx.phys = segment->phys;
2461 
2462 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2463 	if (chan->direction == DMA_MEM_TO_DEV) {
2464 		segment->hw.control |= XILINX_MCDMA_BD_SOP;
2465 		segment = list_last_entry(&desc->segments,
2466 					  struct xilinx_aximcdma_tx_segment,
2467 					  node);
2468 		segment->hw.control |= XILINX_MCDMA_BD_EOP;
2469 	}
2470 
2471 	return &desc->async_tx;
2472 
2473 error:
2474 	xilinx_dma_free_tx_descriptor(chan, desc);
2475 
2476 	return NULL;
2477 }
2478 
2479 /**
2480  * xilinx_dma_terminate_all - Halt the channel and free descriptors
2481  * @dchan: Driver specific DMA Channel pointer
2482  *
2483  * Return: '0' always.
2484  */
2485 static int xilinx_dma_terminate_all(struct dma_chan *dchan)
2486 {
2487 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2488 	u32 reg;
2489 	int err;
2490 
2491 	if (!chan->cyclic) {
2492 		err = chan->stop_transfer(chan);
2493 		if (err) {
2494 			dev_err(chan->dev, "Cannot stop channel %p: %x\n",
2495 				chan, dma_ctrl_read(chan,
2496 				XILINX_DMA_REG_DMASR));
2497 			chan->err = true;
2498 		}
2499 	}
2500 
2501 	xilinx_dma_chan_reset(chan);
2502 	/* Remove and free all of the descriptors in the lists */
2503 	chan->terminating = true;
2504 	xilinx_dma_free_descriptors(chan);
2505 	chan->idle = true;
2506 
2507 	if (chan->cyclic) {
2508 		reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2509 		reg &= ~XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2510 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2511 		chan->cyclic = false;
2512 	}
2513 
2514 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
2515 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2516 			     XILINX_CDMA_CR_SGMODE);
2517 
2518 	return 0;
2519 }
2520 
2521 static void xilinx_dma_synchronize(struct dma_chan *dchan)
2522 {
2523 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2524 
2525 	tasklet_kill(&chan->tasklet);
2526 }
2527 
2528 /**
2529  * xilinx_vdma_channel_set_config - Configure VDMA channel
2530  * Run-time configuration for Axi VDMA, supports:
2531  * . halt the channel
2532  * . configure interrupt coalescing and inter-packet delay threshold
2533  * . start/stop parking
2534  * . enable genlock
2535  *
2536  * @dchan: DMA channel
2537  * @cfg: VDMA device configuration pointer
2538  *
2539  * Return: '0' on success and failure value on error
2540  */
2541 int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
2542 					struct xilinx_vdma_config *cfg)
2543 {
2544 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2545 	u32 dmacr;
2546 
2547 	if (cfg->reset)
2548 		return xilinx_dma_chan_reset(chan);
2549 
2550 	dmacr = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2551 
2552 	chan->config.frm_dly = cfg->frm_dly;
2553 	chan->config.park = cfg->park;
2554 
2555 	/* genlock settings */
2556 	chan->config.gen_lock = cfg->gen_lock;
2557 	chan->config.master = cfg->master;
2558 
2559 	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
2560 	if (cfg->gen_lock && chan->genlock) {
2561 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
2562 		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
2563 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
2564 	}
2565 
2566 	chan->config.frm_cnt_en = cfg->frm_cnt_en;
2567 	chan->config.vflip_en = cfg->vflip_en;
2568 
2569 	if (cfg->park)
2570 		chan->config.park_frm = cfg->park_frm;
2571 	else
2572 		chan->config.park_frm = -1;
2573 
2574 	chan->config.coalesc = cfg->coalesc;
2575 	chan->config.delay = cfg->delay;
2576 
2577 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
2578 		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
2579 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
2580 		chan->config.coalesc = cfg->coalesc;
2581 	}
2582 
2583 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
2584 		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
2585 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
2586 		chan->config.delay = cfg->delay;
2587 	}
2588 
2589 	/* FSync Source selection */
2590 	dmacr &= ~XILINX_DMA_DMACR_FSYNCSRC_MASK;
2591 	dmacr |= cfg->ext_fsync << XILINX_DMA_DMACR_FSYNCSRC_SHIFT;
2592 
2593 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, dmacr);
2594 
2595 	return 0;
2596 }
2597 EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
2598 
2599 /* -----------------------------------------------------------------------------
2600  * Probe and remove
2601  */
2602 
2603 /**
2604  * xilinx_dma_chan_remove - Per Channel remove function
2605  * @chan: Driver specific DMA channel
2606  */
2607 static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
2608 {
2609 	/* Disable all interrupts */
2610 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2611 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
2612 
2613 	if (chan->irq > 0)
2614 		free_irq(chan->irq, chan);
2615 
2616 	tasklet_kill(&chan->tasklet);
2617 
2618 	list_del(&chan->common.device_node);
2619 }
2620 
2621 static int axidma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2622 			    struct clk **tx_clk, struct clk **rx_clk,
2623 			    struct clk **sg_clk, struct clk **tmp_clk)
2624 {
2625 	int err;
2626 
2627 	*tmp_clk = NULL;
2628 
2629 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2630 	if (IS_ERR(*axi_clk))
2631 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2632 
2633 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2634 	if (IS_ERR(*tx_clk))
2635 		*tx_clk = NULL;
2636 
2637 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2638 	if (IS_ERR(*rx_clk))
2639 		*rx_clk = NULL;
2640 
2641 	*sg_clk = devm_clk_get(&pdev->dev, "m_axi_sg_aclk");
2642 	if (IS_ERR(*sg_clk))
2643 		*sg_clk = NULL;
2644 
2645 	err = clk_prepare_enable(*axi_clk);
2646 	if (err) {
2647 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2648 		return err;
2649 	}
2650 
2651 	err = clk_prepare_enable(*tx_clk);
2652 	if (err) {
2653 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2654 		goto err_disable_axiclk;
2655 	}
2656 
2657 	err = clk_prepare_enable(*rx_clk);
2658 	if (err) {
2659 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2660 		goto err_disable_txclk;
2661 	}
2662 
2663 	err = clk_prepare_enable(*sg_clk);
2664 	if (err) {
2665 		dev_err(&pdev->dev, "failed to enable sg_clk (%d)\n", err);
2666 		goto err_disable_rxclk;
2667 	}
2668 
2669 	return 0;
2670 
2671 err_disable_rxclk:
2672 	clk_disable_unprepare(*rx_clk);
2673 err_disable_txclk:
2674 	clk_disable_unprepare(*tx_clk);
2675 err_disable_axiclk:
2676 	clk_disable_unprepare(*axi_clk);
2677 
2678 	return err;
2679 }
2680 
2681 static int axicdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2682 			    struct clk **dev_clk, struct clk **tmp_clk,
2683 			    struct clk **tmp1_clk, struct clk **tmp2_clk)
2684 {
2685 	int err;
2686 
2687 	*tmp_clk = NULL;
2688 	*tmp1_clk = NULL;
2689 	*tmp2_clk = NULL;
2690 
2691 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2692 	if (IS_ERR(*axi_clk))
2693 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2694 
2695 	*dev_clk = devm_clk_get(&pdev->dev, "m_axi_aclk");
2696 	if (IS_ERR(*dev_clk))
2697 		return dev_err_probe(&pdev->dev, PTR_ERR(*dev_clk), "failed to get dev_clk\n");
2698 
2699 	err = clk_prepare_enable(*axi_clk);
2700 	if (err) {
2701 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2702 		return err;
2703 	}
2704 
2705 	err = clk_prepare_enable(*dev_clk);
2706 	if (err) {
2707 		dev_err(&pdev->dev, "failed to enable dev_clk (%d)\n", err);
2708 		goto err_disable_axiclk;
2709 	}
2710 
2711 	return 0;
2712 
2713 err_disable_axiclk:
2714 	clk_disable_unprepare(*axi_clk);
2715 
2716 	return err;
2717 }
2718 
2719 static int axivdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2720 			    struct clk **tx_clk, struct clk **txs_clk,
2721 			    struct clk **rx_clk, struct clk **rxs_clk)
2722 {
2723 	int err;
2724 
2725 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2726 	if (IS_ERR(*axi_clk))
2727 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2728 
2729 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2730 	if (IS_ERR(*tx_clk))
2731 		*tx_clk = NULL;
2732 
2733 	*txs_clk = devm_clk_get(&pdev->dev, "m_axis_mm2s_aclk");
2734 	if (IS_ERR(*txs_clk))
2735 		*txs_clk = NULL;
2736 
2737 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2738 	if (IS_ERR(*rx_clk))
2739 		*rx_clk = NULL;
2740 
2741 	*rxs_clk = devm_clk_get(&pdev->dev, "s_axis_s2mm_aclk");
2742 	if (IS_ERR(*rxs_clk))
2743 		*rxs_clk = NULL;
2744 
2745 	err = clk_prepare_enable(*axi_clk);
2746 	if (err) {
2747 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n",
2748 			err);
2749 		return err;
2750 	}
2751 
2752 	err = clk_prepare_enable(*tx_clk);
2753 	if (err) {
2754 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2755 		goto err_disable_axiclk;
2756 	}
2757 
2758 	err = clk_prepare_enable(*txs_clk);
2759 	if (err) {
2760 		dev_err(&pdev->dev, "failed to enable txs_clk (%d)\n", err);
2761 		goto err_disable_txclk;
2762 	}
2763 
2764 	err = clk_prepare_enable(*rx_clk);
2765 	if (err) {
2766 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2767 		goto err_disable_txsclk;
2768 	}
2769 
2770 	err = clk_prepare_enable(*rxs_clk);
2771 	if (err) {
2772 		dev_err(&pdev->dev, "failed to enable rxs_clk (%d)\n", err);
2773 		goto err_disable_rxclk;
2774 	}
2775 
2776 	return 0;
2777 
2778 err_disable_rxclk:
2779 	clk_disable_unprepare(*rx_clk);
2780 err_disable_txsclk:
2781 	clk_disable_unprepare(*txs_clk);
2782 err_disable_txclk:
2783 	clk_disable_unprepare(*tx_clk);
2784 err_disable_axiclk:
2785 	clk_disable_unprepare(*axi_clk);
2786 
2787 	return err;
2788 }
2789 
2790 static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
2791 {
2792 	clk_disable_unprepare(xdev->rxs_clk);
2793 	clk_disable_unprepare(xdev->rx_clk);
2794 	clk_disable_unprepare(xdev->txs_clk);
2795 	clk_disable_unprepare(xdev->tx_clk);
2796 	clk_disable_unprepare(xdev->axi_clk);
2797 }
2798 
2799 /**
2800  * xilinx_dma_chan_probe - Per Channel Probing
2801  * It get channel features from the device tree entry and
2802  * initialize special channel handling routines
2803  *
2804  * @xdev: Driver specific device structure
2805  * @node: Device node
2806  *
2807  * Return: '0' on success and failure value on error
2808  */
2809 static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
2810 				  struct device_node *node)
2811 {
2812 	struct xilinx_dma_chan *chan;
2813 	bool has_dre = false;
2814 	u32 value, width;
2815 	int err;
2816 
2817 	/* Allocate and initialize the channel structure */
2818 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
2819 	if (!chan)
2820 		return -ENOMEM;
2821 
2822 	chan->dev = xdev->dev;
2823 	chan->xdev = xdev;
2824 	chan->desc_pendingcount = 0x0;
2825 	chan->ext_addr = xdev->ext_addr;
2826 	/* This variable ensures that descriptors are not
2827 	 * Submitted when dma engine is in progress. This variable is
2828 	 * Added to avoid polling for a bit in the status register to
2829 	 * Know dma state in the driver hot path.
2830 	 */
2831 	chan->idle = true;
2832 
2833 	spin_lock_init(&chan->lock);
2834 	INIT_LIST_HEAD(&chan->pending_list);
2835 	INIT_LIST_HEAD(&chan->done_list);
2836 	INIT_LIST_HEAD(&chan->active_list);
2837 	INIT_LIST_HEAD(&chan->free_seg_list);
2838 
2839 	/* Retrieve the channel properties from the device tree */
2840 	has_dre = of_property_read_bool(node, "xlnx,include-dre");
2841 
2842 	of_property_read_u8(node, "xlnx,irq-delay", &chan->irq_delay);
2843 
2844 	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
2845 
2846 	err = of_property_read_u32(node, "xlnx,datawidth", &value);
2847 	if (err) {
2848 		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
2849 		return err;
2850 	}
2851 	width = value >> 3; /* Convert bits to bytes */
2852 
2853 	/* If data width is greater than 8 bytes, DRE is not in hw */
2854 	if (width > 8)
2855 		has_dre = false;
2856 
2857 	if (!has_dre)
2858 		xdev->common.copy_align = (enum dmaengine_alignment)fls(width - 1);
2859 
2860 	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel") ||
2861 	    of_device_is_compatible(node, "xlnx,axi-dma-mm2s-channel") ||
2862 	    of_device_is_compatible(node, "xlnx,axi-cdma-channel")) {
2863 		chan->direction = DMA_MEM_TO_DEV;
2864 		chan->id = xdev->mm2s_chan_id++;
2865 		chan->tdest = chan->id;
2866 
2867 		chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
2868 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2869 			chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
2870 			chan->config.park = 1;
2871 
2872 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2873 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
2874 				chan->flush_on_fsync = true;
2875 		}
2876 	} else if (of_device_is_compatible(node,
2877 					   "xlnx,axi-vdma-s2mm-channel") ||
2878 		   of_device_is_compatible(node,
2879 					   "xlnx,axi-dma-s2mm-channel")) {
2880 		chan->direction = DMA_DEV_TO_MEM;
2881 		chan->id = xdev->s2mm_chan_id++;
2882 		chan->tdest = chan->id - xdev->dma_config->max_channels / 2;
2883 		chan->has_vflip = of_property_read_bool(node,
2884 					"xlnx,enable-vert-flip");
2885 		if (chan->has_vflip) {
2886 			chan->config.vflip_en = dma_read(chan,
2887 				XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP) &
2888 				XILINX_VDMA_ENABLE_VERTICAL_FLIP;
2889 		}
2890 
2891 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
2892 			chan->ctrl_offset = XILINX_MCDMA_S2MM_CTRL_OFFSET;
2893 		else
2894 			chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
2895 
2896 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2897 			chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
2898 			chan->config.park = 1;
2899 
2900 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2901 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
2902 				chan->flush_on_fsync = true;
2903 		}
2904 	} else {
2905 		dev_err(xdev->dev, "Invalid channel compatible node\n");
2906 		return -EINVAL;
2907 	}
2908 
2909 	/* Request the interrupt */
2910 	chan->irq = of_irq_get(node, chan->tdest);
2911 	if (chan->irq < 0)
2912 		return dev_err_probe(xdev->dev, chan->irq, "failed to get irq\n");
2913 	err = request_irq(chan->irq, xdev->dma_config->irq_handler,
2914 			  IRQF_SHARED, "xilinx-dma-controller", chan);
2915 	if (err) {
2916 		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
2917 		return err;
2918 	}
2919 
2920 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
2921 		chan->start_transfer = xilinx_dma_start_transfer;
2922 		chan->stop_transfer = xilinx_dma_stop_transfer;
2923 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
2924 		chan->start_transfer = xilinx_mcdma_start_transfer;
2925 		chan->stop_transfer = xilinx_dma_stop_transfer;
2926 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
2927 		chan->start_transfer = xilinx_cdma_start_transfer;
2928 		chan->stop_transfer = xilinx_cdma_stop_transfer;
2929 	} else {
2930 		chan->start_transfer = xilinx_vdma_start_transfer;
2931 		chan->stop_transfer = xilinx_dma_stop_transfer;
2932 	}
2933 
2934 	/* check if SG is enabled (only for AXIDMA, AXIMCDMA, and CDMA) */
2935 	if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) {
2936 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA ||
2937 		    dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) &
2938 			    XILINX_DMA_DMASR_SG_MASK)
2939 			chan->has_sg = true;
2940 		dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id,
2941 			chan->has_sg ? "enabled" : "disabled");
2942 	}
2943 
2944 	/* Initialize the tasklet */
2945 	tasklet_setup(&chan->tasklet, xilinx_dma_do_tasklet);
2946 
2947 	/*
2948 	 * Initialize the DMA channel and add it to the DMA engine channels
2949 	 * list.
2950 	 */
2951 	chan->common.device = &xdev->common;
2952 
2953 	list_add_tail(&chan->common.device_node, &xdev->common.channels);
2954 	xdev->chan[chan->id] = chan;
2955 
2956 	/* Reset the channel */
2957 	err = xilinx_dma_chan_reset(chan);
2958 	if (err < 0) {
2959 		dev_err(xdev->dev, "Reset channel failed\n");
2960 		return err;
2961 	}
2962 
2963 	return 0;
2964 }
2965 
2966 /**
2967  * xilinx_dma_child_probe - Per child node probe
2968  * It get number of dma-channels per child node from
2969  * device-tree and initializes all the channels.
2970  *
2971  * @xdev: Driver specific device structure
2972  * @node: Device node
2973  *
2974  * Return: '0' on success and failure value on error.
2975  */
2976 static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
2977 				    struct device_node *node)
2978 {
2979 	int ret, i;
2980 	u32 nr_channels = 1;
2981 
2982 	ret = of_property_read_u32(node, "dma-channels", &nr_channels);
2983 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA && ret < 0)
2984 		dev_warn(xdev->dev, "missing dma-channels property\n");
2985 
2986 	for (i = 0; i < nr_channels; i++) {
2987 		ret = xilinx_dma_chan_probe(xdev, node);
2988 		if (ret)
2989 			return ret;
2990 	}
2991 
2992 	return 0;
2993 }
2994 
2995 /**
2996  * of_dma_xilinx_xlate - Translation function
2997  * @dma_spec: Pointer to DMA specifier as found in the device tree
2998  * @ofdma: Pointer to DMA controller data
2999  *
3000  * Return: DMA channel pointer on success and NULL on error
3001  */
3002 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
3003 						struct of_dma *ofdma)
3004 {
3005 	struct xilinx_dma_device *xdev = ofdma->of_dma_data;
3006 	int chan_id = dma_spec->args[0];
3007 
3008 	if (chan_id >= xdev->dma_config->max_channels || !xdev->chan[chan_id])
3009 		return NULL;
3010 
3011 	return dma_get_slave_channel(&xdev->chan[chan_id]->common);
3012 }
3013 
3014 static const struct xilinx_dma_config axidma_config = {
3015 	.dmatype = XDMA_TYPE_AXIDMA,
3016 	.clk_init = axidma_clk_init,
3017 	.irq_handler = xilinx_dma_irq_handler,
3018 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3019 };
3020 
3021 static const struct xilinx_dma_config aximcdma_config = {
3022 	.dmatype = XDMA_TYPE_AXIMCDMA,
3023 	.clk_init = axidma_clk_init,
3024 	.irq_handler = xilinx_mcdma_irq_handler,
3025 	.max_channels = XILINX_MCDMA_MAX_CHANS_PER_DEVICE,
3026 };
3027 static const struct xilinx_dma_config axicdma_config = {
3028 	.dmatype = XDMA_TYPE_CDMA,
3029 	.clk_init = axicdma_clk_init,
3030 	.irq_handler = xilinx_dma_irq_handler,
3031 	.max_channels = XILINX_CDMA_MAX_CHANS_PER_DEVICE,
3032 };
3033 
3034 static const struct xilinx_dma_config axivdma_config = {
3035 	.dmatype = XDMA_TYPE_VDMA,
3036 	.clk_init = axivdma_clk_init,
3037 	.irq_handler = xilinx_dma_irq_handler,
3038 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3039 };
3040 
3041 static const struct of_device_id xilinx_dma_of_ids[] = {
3042 	{ .compatible = "xlnx,axi-dma-1.00.a", .data = &axidma_config },
3043 	{ .compatible = "xlnx,axi-cdma-1.00.a", .data = &axicdma_config },
3044 	{ .compatible = "xlnx,axi-vdma-1.00.a", .data = &axivdma_config },
3045 	{ .compatible = "xlnx,axi-mcdma-1.00.a", .data = &aximcdma_config },
3046 	{}
3047 };
3048 MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
3049 
3050 /**
3051  * xilinx_dma_probe - Driver probe function
3052  * @pdev: Pointer to the platform_device structure
3053  *
3054  * Return: '0' on success and failure value on error
3055  */
3056 static int xilinx_dma_probe(struct platform_device *pdev)
3057 {
3058 	int (*clk_init)(struct platform_device *, struct clk **, struct clk **,
3059 			struct clk **, struct clk **, struct clk **)
3060 					= axivdma_clk_init;
3061 	struct device_node *node = pdev->dev.of_node;
3062 	struct xilinx_dma_device *xdev;
3063 	struct device_node *child, *np = pdev->dev.of_node;
3064 	u32 num_frames, addr_width, len_width;
3065 	int i, err;
3066 
3067 	/* Allocate and initialize the DMA engine structure */
3068 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
3069 	if (!xdev)
3070 		return -ENOMEM;
3071 
3072 	xdev->dev = &pdev->dev;
3073 	if (np) {
3074 		const struct of_device_id *match;
3075 
3076 		match = of_match_node(xilinx_dma_of_ids, np);
3077 		if (match && match->data) {
3078 			xdev->dma_config = match->data;
3079 			clk_init = xdev->dma_config->clk_init;
3080 		}
3081 	}
3082 
3083 	err = clk_init(pdev, &xdev->axi_clk, &xdev->tx_clk, &xdev->txs_clk,
3084 		       &xdev->rx_clk, &xdev->rxs_clk);
3085 	if (err)
3086 		return err;
3087 
3088 	/* Request and map I/O memory */
3089 	xdev->regs = devm_platform_ioremap_resource(pdev, 0);
3090 	if (IS_ERR(xdev->regs)) {
3091 		err = PTR_ERR(xdev->regs);
3092 		goto disable_clks;
3093 	}
3094 	/* Retrieve the DMA engine properties from the device tree */
3095 	xdev->max_buffer_len = GENMASK(XILINX_DMA_MAX_TRANS_LEN_MAX - 1, 0);
3096 	xdev->s2mm_chan_id = xdev->dma_config->max_channels / 2;
3097 
3098 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA ||
3099 	    xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3100 		if (!of_property_read_u32(node, "xlnx,sg-length-width",
3101 					  &len_width)) {
3102 			if (len_width < XILINX_DMA_MAX_TRANS_LEN_MIN ||
3103 			    len_width > XILINX_DMA_V2_MAX_TRANS_LEN_MAX) {
3104 				dev_warn(xdev->dev,
3105 					 "invalid xlnx,sg-length-width property value. Using default width\n");
3106 			} else {
3107 				if (len_width > XILINX_DMA_MAX_TRANS_LEN_MAX)
3108 					dev_warn(xdev->dev, "Please ensure that IP supports buffer length > 23 bits\n");
3109 				xdev->max_buffer_len =
3110 					GENMASK(len_width - 1, 0);
3111 			}
3112 		}
3113 	}
3114 
3115 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3116 		xdev->has_axistream_connected =
3117 			of_property_read_bool(node, "xlnx,axistream-connected");
3118 	}
3119 
3120 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3121 		err = of_property_read_u32(node, "xlnx,num-fstores",
3122 					   &num_frames);
3123 		if (err < 0) {
3124 			dev_err(xdev->dev,
3125 				"missing xlnx,num-fstores property\n");
3126 			goto disable_clks;
3127 		}
3128 
3129 		err = of_property_read_u32(node, "xlnx,flush-fsync",
3130 					   &xdev->flush_on_fsync);
3131 		if (err < 0)
3132 			dev_warn(xdev->dev,
3133 				 "missing xlnx,flush-fsync property\n");
3134 	}
3135 
3136 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
3137 	if (err < 0)
3138 		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
3139 
3140 	if (addr_width > 32)
3141 		xdev->ext_addr = true;
3142 	else
3143 		xdev->ext_addr = false;
3144 
3145 	/* Set metadata mode */
3146 	if (xdev->has_axistream_connected)
3147 		xdev->common.desc_metadata_modes = DESC_METADATA_ENGINE;
3148 
3149 	/* Set the dma mask bits */
3150 	err = dma_set_mask_and_coherent(xdev->dev, DMA_BIT_MASK(addr_width));
3151 	if (err < 0) {
3152 		dev_err(xdev->dev, "DMA mask error %d\n", err);
3153 		goto disable_clks;
3154 	}
3155 
3156 	/* Initialize the DMA engine */
3157 	xdev->common.dev = &pdev->dev;
3158 
3159 	INIT_LIST_HEAD(&xdev->common.channels);
3160 	if (!(xdev->dma_config->dmatype == XDMA_TYPE_CDMA)) {
3161 		dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
3162 		dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
3163 	}
3164 
3165 	xdev->common.device_alloc_chan_resources =
3166 				xilinx_dma_alloc_chan_resources;
3167 	xdev->common.device_free_chan_resources =
3168 				xilinx_dma_free_chan_resources;
3169 	xdev->common.device_terminate_all = xilinx_dma_terminate_all;
3170 	xdev->common.device_synchronize = xilinx_dma_synchronize;
3171 	xdev->common.device_tx_status = xilinx_dma_tx_status;
3172 	xdev->common.device_issue_pending = xilinx_dma_issue_pending;
3173 	xdev->common.device_config = xilinx_dma_device_config;
3174 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3175 		dma_cap_set(DMA_CYCLIC, xdev->common.cap_mask);
3176 		xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
3177 		xdev->common.device_prep_dma_cyclic =
3178 					  xilinx_dma_prep_dma_cyclic;
3179 		/* Residue calculation is supported by only AXI DMA and CDMA */
3180 		xdev->common.residue_granularity =
3181 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3182 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
3183 		dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
3184 		xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
3185 		/* Residue calculation is supported by only AXI DMA and CDMA */
3186 		xdev->common.residue_granularity =
3187 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3188 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3189 		xdev->common.device_prep_slave_sg = xilinx_mcdma_prep_slave_sg;
3190 	} else {
3191 		xdev->common.device_prep_interleaved_dma =
3192 				xilinx_vdma_dma_prep_interleaved;
3193 	}
3194 
3195 	platform_set_drvdata(pdev, xdev);
3196 
3197 	/* Initialize the channels */
3198 	for_each_child_of_node(node, child) {
3199 		err = xilinx_dma_child_probe(xdev, child);
3200 		if (err < 0) {
3201 			of_node_put(child);
3202 			goto error;
3203 		}
3204 	}
3205 
3206 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3207 		for (i = 0; i < xdev->dma_config->max_channels; i++)
3208 			if (xdev->chan[i])
3209 				xdev->chan[i]->num_frms = num_frames;
3210 	}
3211 
3212 	/* Register the DMA engine with the core */
3213 	err = dma_async_device_register(&xdev->common);
3214 	if (err) {
3215 		dev_err(xdev->dev, "failed to register the dma device\n");
3216 		goto error;
3217 	}
3218 
3219 	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
3220 					 xdev);
3221 	if (err < 0) {
3222 		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
3223 		dma_async_device_unregister(&xdev->common);
3224 		goto error;
3225 	}
3226 
3227 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
3228 		dev_info(&pdev->dev, "Xilinx AXI DMA Engine Driver Probed!!\n");
3229 	else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA)
3230 		dev_info(&pdev->dev, "Xilinx AXI CDMA Engine Driver Probed!!\n");
3231 	else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
3232 		dev_info(&pdev->dev, "Xilinx AXI MCDMA Engine Driver Probed!!\n");
3233 	else
3234 		dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
3235 
3236 	return 0;
3237 
3238 error:
3239 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3240 		if (xdev->chan[i])
3241 			xilinx_dma_chan_remove(xdev->chan[i]);
3242 disable_clks:
3243 	xdma_disable_allclks(xdev);
3244 
3245 	return err;
3246 }
3247 
3248 /**
3249  * xilinx_dma_remove - Driver remove function
3250  * @pdev: Pointer to the platform_device structure
3251  */
3252 static void xilinx_dma_remove(struct platform_device *pdev)
3253 {
3254 	struct xilinx_dma_device *xdev = platform_get_drvdata(pdev);
3255 	int i;
3256 
3257 	of_dma_controller_free(pdev->dev.of_node);
3258 
3259 	dma_async_device_unregister(&xdev->common);
3260 
3261 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3262 		if (xdev->chan[i])
3263 			xilinx_dma_chan_remove(xdev->chan[i]);
3264 
3265 	xdma_disable_allclks(xdev);
3266 }
3267 
3268 static struct platform_driver xilinx_vdma_driver = {
3269 	.driver = {
3270 		.name = "xilinx-vdma",
3271 		.of_match_table = xilinx_dma_of_ids,
3272 	},
3273 	.probe = xilinx_dma_probe,
3274 	.remove_new = xilinx_dma_remove,
3275 };
3276 
3277 module_platform_driver(xilinx_vdma_driver);
3278 
3279 MODULE_AUTHOR("Xilinx, Inc.");
3280 MODULE_DESCRIPTION("Xilinx VDMA driver");
3281 MODULE_LICENSE("GPL v2");
3282