xref: /openbmc/linux/drivers/dma/xilinx/xilinx_dma.c (revision 15e3ae36)
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_address.h>
45 #include <linux/of_dma.h>
46 #include <linux/of_platform.h>
47 #include <linux/of_irq.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_REG_HSIZE			0x0004
116 
117 #define XILINX_DMA_REG_FRMDLY_STRIDE		0x0008
118 #define XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT	24
119 #define XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT	0
120 
121 #define XILINX_VDMA_REG_START_ADDRESS(n)	(0x000c + 4 * (n))
122 #define XILINX_VDMA_REG_START_ADDRESS_64(n)	(0x000c + 8 * (n))
123 
124 #define XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP	0x00ec
125 #define XILINX_VDMA_ENABLE_VERTICAL_FLIP	BIT(0)
126 
127 /* HW specific definitions */
128 #define XILINX_MCDMA_MAX_CHANS_PER_DEVICE	0x20
129 #define XILINX_DMA_MAX_CHANS_PER_DEVICE		0x2
130 #define XILINX_CDMA_MAX_CHANS_PER_DEVICE	0x1
131 
132 #define XILINX_DMA_DMAXR_ALL_IRQ_MASK	\
133 		(XILINX_DMA_DMASR_FRM_CNT_IRQ | \
134 		 XILINX_DMA_DMASR_DLY_CNT_IRQ | \
135 		 XILINX_DMA_DMASR_ERR_IRQ)
136 
137 #define XILINX_DMA_DMASR_ALL_ERR_MASK	\
138 		(XILINX_DMA_DMASR_EOL_LATE_ERR | \
139 		 XILINX_DMA_DMASR_SOF_LATE_ERR | \
140 		 XILINX_DMA_DMASR_SG_DEC_ERR | \
141 		 XILINX_DMA_DMASR_SG_SLV_ERR | \
142 		 XILINX_DMA_DMASR_EOF_EARLY_ERR | \
143 		 XILINX_DMA_DMASR_SOF_EARLY_ERR | \
144 		 XILINX_DMA_DMASR_DMA_DEC_ERR | \
145 		 XILINX_DMA_DMASR_DMA_SLAVE_ERR | \
146 		 XILINX_DMA_DMASR_DMA_INT_ERR)
147 
148 /*
149  * Recoverable errors are DMA Internal error, SOF Early, EOF Early
150  * and SOF Late. They are only recoverable when C_FLUSH_ON_FSYNC
151  * is enabled in the h/w system.
152  */
153 #define XILINX_DMA_DMASR_ERR_RECOVER_MASK	\
154 		(XILINX_DMA_DMASR_SOF_LATE_ERR | \
155 		 XILINX_DMA_DMASR_EOF_EARLY_ERR | \
156 		 XILINX_DMA_DMASR_SOF_EARLY_ERR | \
157 		 XILINX_DMA_DMASR_DMA_INT_ERR)
158 
159 /* Axi VDMA Flush on Fsync bits */
160 #define XILINX_DMA_FLUSH_S2MM		3
161 #define XILINX_DMA_FLUSH_MM2S		2
162 #define XILINX_DMA_FLUSH_BOTH		1
163 
164 /* Delay loop counter to prevent hardware failure */
165 #define XILINX_DMA_LOOP_COUNT		1000000
166 
167 /* AXI DMA Specific Registers/Offsets */
168 #define XILINX_DMA_REG_SRCDSTADDR	0x18
169 #define XILINX_DMA_REG_BTT		0x28
170 
171 /* AXI DMA Specific Masks/Bit fields */
172 #define XILINX_DMA_MAX_TRANS_LEN_MIN	8
173 #define XILINX_DMA_MAX_TRANS_LEN_MAX	23
174 #define XILINX_DMA_V2_MAX_TRANS_LEN_MAX	26
175 #define XILINX_DMA_CR_COALESCE_MAX	GENMASK(23, 16)
176 #define XILINX_DMA_CR_CYCLIC_BD_EN_MASK	BIT(4)
177 #define XILINX_DMA_CR_COALESCE_SHIFT	16
178 #define XILINX_DMA_BD_SOP		BIT(27)
179 #define XILINX_DMA_BD_EOP		BIT(26)
180 #define XILINX_DMA_COALESCE_MAX		255
181 #define XILINX_DMA_NUM_DESCS		255
182 #define XILINX_DMA_NUM_APP_WORDS	5
183 
184 /* AXI CDMA Specific Registers/Offsets */
185 #define XILINX_CDMA_REG_SRCADDR		0x18
186 #define XILINX_CDMA_REG_DSTADDR		0x20
187 
188 /* AXI CDMA Specific Masks */
189 #define XILINX_CDMA_CR_SGMODE          BIT(3)
190 
191 #define xilinx_prep_dma_addr_t(addr)	\
192 	((dma_addr_t)((u64)addr##_##msb << 32 | (addr)))
193 
194 /* AXI MCDMA Specific Registers/Offsets */
195 #define XILINX_MCDMA_MM2S_CTRL_OFFSET		0x0000
196 #define XILINX_MCDMA_S2MM_CTRL_OFFSET		0x0500
197 #define XILINX_MCDMA_CHEN_OFFSET		0x0008
198 #define XILINX_MCDMA_CH_ERR_OFFSET		0x0010
199 #define XILINX_MCDMA_RXINT_SER_OFFSET		0x0020
200 #define XILINX_MCDMA_TXINT_SER_OFFSET		0x0028
201 #define XILINX_MCDMA_CHAN_CR_OFFSET(x)		(0x40 + (x) * 0x40)
202 #define XILINX_MCDMA_CHAN_SR_OFFSET(x)		(0x44 + (x) * 0x40)
203 #define XILINX_MCDMA_CHAN_CDESC_OFFSET(x)	(0x48 + (x) * 0x40)
204 #define XILINX_MCDMA_CHAN_TDESC_OFFSET(x)	(0x50 + (x) * 0x40)
205 
206 /* AXI MCDMA Specific Masks/Shifts */
207 #define XILINX_MCDMA_COALESCE_SHIFT		16
208 #define XILINX_MCDMA_COALESCE_MAX		24
209 #define XILINX_MCDMA_IRQ_ALL_MASK		GENMASK(7, 5)
210 #define XILINX_MCDMA_COALESCE_MASK		GENMASK(23, 16)
211 #define XILINX_MCDMA_CR_RUNSTOP_MASK		BIT(0)
212 #define XILINX_MCDMA_IRQ_IOC_MASK		BIT(5)
213 #define XILINX_MCDMA_IRQ_DELAY_MASK		BIT(6)
214 #define XILINX_MCDMA_IRQ_ERR_MASK		BIT(7)
215 #define XILINX_MCDMA_BD_EOP			BIT(30)
216 #define XILINX_MCDMA_BD_SOP			BIT(31)
217 
218 /**
219  * struct xilinx_vdma_desc_hw - Hardware Descriptor
220  * @next_desc: Next Descriptor Pointer @0x00
221  * @pad1: Reserved @0x04
222  * @buf_addr: Buffer address @0x08
223  * @buf_addr_msb: MSB of Buffer address @0x0C
224  * @vsize: Vertical Size @0x10
225  * @hsize: Horizontal Size @0x14
226  * @stride: Number of bytes between the first
227  *	    pixels of each horizontal line @0x18
228  */
229 struct xilinx_vdma_desc_hw {
230 	u32 next_desc;
231 	u32 pad1;
232 	u32 buf_addr;
233 	u32 buf_addr_msb;
234 	u32 vsize;
235 	u32 hsize;
236 	u32 stride;
237 } __aligned(64);
238 
239 /**
240  * struct xilinx_axidma_desc_hw - Hardware Descriptor for AXI DMA
241  * @next_desc: Next Descriptor Pointer @0x00
242  * @next_desc_msb: MSB of Next Descriptor Pointer @0x04
243  * @buf_addr: Buffer address @0x08
244  * @buf_addr_msb: MSB of Buffer address @0x0C
245  * @reserved1: Reserved @0x10
246  * @reserved2: Reserved @0x14
247  * @control: Control field @0x18
248  * @status: Status field @0x1C
249  * @app: APP Fields @0x20 - 0x30
250  */
251 struct xilinx_axidma_desc_hw {
252 	u32 next_desc;
253 	u32 next_desc_msb;
254 	u32 buf_addr;
255 	u32 buf_addr_msb;
256 	u32 reserved1;
257 	u32 reserved2;
258 	u32 control;
259 	u32 status;
260 	u32 app[XILINX_DMA_NUM_APP_WORDS];
261 } __aligned(64);
262 
263 /**
264  * struct xilinx_aximcdma_desc_hw - Hardware Descriptor for AXI MCDMA
265  * @next_desc: Next Descriptor Pointer @0x00
266  * @next_desc_msb: MSB of Next Descriptor Pointer @0x04
267  * @buf_addr: Buffer address @0x08
268  * @buf_addr_msb: MSB of Buffer address @0x0C
269  * @rsvd: Reserved field @0x10
270  * @control: Control Information field @0x14
271  * @status: Status field @0x18
272  * @sideband_status: Status of sideband signals @0x1C
273  * @app: APP Fields @0x20 - 0x30
274  */
275 struct xilinx_aximcdma_desc_hw {
276 	u32 next_desc;
277 	u32 next_desc_msb;
278 	u32 buf_addr;
279 	u32 buf_addr_msb;
280 	u32 rsvd;
281 	u32 control;
282 	u32 status;
283 	u32 sideband_status;
284 	u32 app[XILINX_DMA_NUM_APP_WORDS];
285 } __aligned(64);
286 
287 /**
288  * struct xilinx_cdma_desc_hw - Hardware Descriptor
289  * @next_desc: Next Descriptor Pointer @0x00
290  * @next_desc_msb: Next Descriptor Pointer MSB @0x04
291  * @src_addr: Source address @0x08
292  * @src_addr_msb: Source address MSB @0x0C
293  * @dest_addr: Destination address @0x10
294  * @dest_addr_msb: Destination address MSB @0x14
295  * @control: Control field @0x18
296  * @status: Status field @0x1C
297  */
298 struct xilinx_cdma_desc_hw {
299 	u32 next_desc;
300 	u32 next_desc_msb;
301 	u32 src_addr;
302 	u32 src_addr_msb;
303 	u32 dest_addr;
304 	u32 dest_addr_msb;
305 	u32 control;
306 	u32 status;
307 } __aligned(64);
308 
309 /**
310  * struct xilinx_vdma_tx_segment - Descriptor segment
311  * @hw: Hardware descriptor
312  * @node: Node in the descriptor segments list
313  * @phys: Physical address of segment
314  */
315 struct xilinx_vdma_tx_segment {
316 	struct xilinx_vdma_desc_hw hw;
317 	struct list_head node;
318 	dma_addr_t phys;
319 } __aligned(64);
320 
321 /**
322  * struct xilinx_axidma_tx_segment - Descriptor segment
323  * @hw: Hardware descriptor
324  * @node: Node in the descriptor segments list
325  * @phys: Physical address of segment
326  */
327 struct xilinx_axidma_tx_segment {
328 	struct xilinx_axidma_desc_hw hw;
329 	struct list_head node;
330 	dma_addr_t phys;
331 } __aligned(64);
332 
333 /**
334  * struct xilinx_aximcdma_tx_segment - Descriptor segment
335  * @hw: Hardware descriptor
336  * @node: Node in the descriptor segments list
337  * @phys: Physical address of segment
338  */
339 struct xilinx_aximcdma_tx_segment {
340 	struct xilinx_aximcdma_desc_hw hw;
341 	struct list_head node;
342 	dma_addr_t phys;
343 } __aligned(64);
344 
345 /**
346  * struct xilinx_cdma_tx_segment - Descriptor segment
347  * @hw: Hardware descriptor
348  * @node: Node in the descriptor segments list
349  * @phys: Physical address of segment
350  */
351 struct xilinx_cdma_tx_segment {
352 	struct xilinx_cdma_desc_hw hw;
353 	struct list_head node;
354 	dma_addr_t phys;
355 } __aligned(64);
356 
357 /**
358  * struct xilinx_dma_tx_descriptor - Per Transaction structure
359  * @async_tx: Async transaction descriptor
360  * @segments: TX segments list
361  * @node: Node in the channel descriptors list
362  * @cyclic: Check for cyclic transfers.
363  * @err: Whether the descriptor has an error.
364  * @residue: Residue of the completed descriptor
365  */
366 struct xilinx_dma_tx_descriptor {
367 	struct dma_async_tx_descriptor async_tx;
368 	struct list_head segments;
369 	struct list_head node;
370 	bool cyclic;
371 	bool err;
372 	u32 residue;
373 };
374 
375 /**
376  * struct xilinx_dma_chan - Driver specific DMA channel structure
377  * @xdev: Driver specific device structure
378  * @ctrl_offset: Control registers offset
379  * @desc_offset: TX descriptor registers offset
380  * @lock: Descriptor operation lock
381  * @pending_list: Descriptors waiting
382  * @active_list: Descriptors ready to submit
383  * @done_list: Complete descriptors
384  * @free_seg_list: Free descriptors
385  * @common: DMA common channel
386  * @desc_pool: Descriptors pool
387  * @dev: The dma device
388  * @irq: Channel IRQ
389  * @id: Channel ID
390  * @direction: Transfer direction
391  * @num_frms: Number of frames
392  * @has_sg: Support scatter transfers
393  * @cyclic: Check for cyclic transfers.
394  * @genlock: Support genlock mode
395  * @err: Channel has errors
396  * @idle: Check for channel idle
397  * @tasklet: Cleanup work after irq
398  * @config: Device configuration info
399  * @flush_on_fsync: Flush on Frame sync
400  * @desc_pendingcount: Descriptor pending count
401  * @ext_addr: Indicates 64 bit addressing is supported by dma channel
402  * @desc_submitcount: Descriptor h/w submitted count
403  * @seg_v: Statically allocated segments base
404  * @seg_mv: Statically allocated segments base for MCDMA
405  * @seg_p: Physical allocated segments base
406  * @cyclic_seg_v: Statically allocated segment base for cyclic transfers
407  * @cyclic_seg_p: Physical allocated segments base for cyclic dma
408  * @start_transfer: Differentiate b/w DMA IP's transfer
409  * @stop_transfer: Differentiate b/w DMA IP's quiesce
410  * @tdest: TDEST value for mcdma
411  * @has_vflip: S2MM vertical flip
412  */
413 struct xilinx_dma_chan {
414 	struct xilinx_dma_device *xdev;
415 	u32 ctrl_offset;
416 	u32 desc_offset;
417 	spinlock_t lock;
418 	struct list_head pending_list;
419 	struct list_head active_list;
420 	struct list_head done_list;
421 	struct list_head free_seg_list;
422 	struct dma_chan common;
423 	struct dma_pool *desc_pool;
424 	struct device *dev;
425 	int irq;
426 	int id;
427 	enum dma_transfer_direction direction;
428 	int num_frms;
429 	bool has_sg;
430 	bool cyclic;
431 	bool genlock;
432 	bool err;
433 	bool idle;
434 	struct tasklet_struct tasklet;
435 	struct xilinx_vdma_config config;
436 	bool flush_on_fsync;
437 	u32 desc_pendingcount;
438 	bool ext_addr;
439 	u32 desc_submitcount;
440 	struct xilinx_axidma_tx_segment *seg_v;
441 	struct xilinx_aximcdma_tx_segment *seg_mv;
442 	dma_addr_t seg_p;
443 	struct xilinx_axidma_tx_segment *cyclic_seg_v;
444 	dma_addr_t cyclic_seg_p;
445 	void (*start_transfer)(struct xilinx_dma_chan *chan);
446 	int (*stop_transfer)(struct xilinx_dma_chan *chan);
447 	u16 tdest;
448 	bool has_vflip;
449 };
450 
451 /**
452  * enum xdma_ip_type - DMA IP type.
453  *
454  * @XDMA_TYPE_AXIDMA: Axi dma ip.
455  * @XDMA_TYPE_CDMA: Axi cdma ip.
456  * @XDMA_TYPE_VDMA: Axi vdma ip.
457  * @XDMA_TYPE_AXIMCDMA: Axi MCDMA ip.
458  *
459  */
460 enum xdma_ip_type {
461 	XDMA_TYPE_AXIDMA = 0,
462 	XDMA_TYPE_CDMA,
463 	XDMA_TYPE_VDMA,
464 	XDMA_TYPE_AXIMCDMA
465 };
466 
467 struct xilinx_dma_config {
468 	enum xdma_ip_type dmatype;
469 	int (*clk_init)(struct platform_device *pdev, struct clk **axi_clk,
470 			struct clk **tx_clk, struct clk **txs_clk,
471 			struct clk **rx_clk, struct clk **rxs_clk);
472 	irqreturn_t (*irq_handler)(int irq, void *data);
473 	const int max_channels;
474 };
475 
476 /**
477  * struct xilinx_dma_device - DMA device structure
478  * @regs: I/O mapped base address
479  * @dev: Device Structure
480  * @common: DMA device structure
481  * @chan: Driver specific DMA channel
482  * @flush_on_fsync: Flush on frame sync
483  * @ext_addr: Indicates 64 bit addressing is supported by dma device
484  * @pdev: Platform device structure pointer
485  * @dma_config: DMA config structure
486  * @axi_clk: DMA Axi4-lite interace clock
487  * @tx_clk: DMA mm2s clock
488  * @txs_clk: DMA mm2s stream clock
489  * @rx_clk: DMA s2mm clock
490  * @rxs_clk: DMA s2mm stream clock
491  * @s2mm_chan_id: DMA s2mm channel identifier
492  * @mm2s_chan_id: DMA mm2s channel identifier
493  * @max_buffer_len: Max buffer length
494  */
495 struct xilinx_dma_device {
496 	void __iomem *regs;
497 	struct device *dev;
498 	struct dma_device common;
499 	struct xilinx_dma_chan *chan[XILINX_MCDMA_MAX_CHANS_PER_DEVICE];
500 	u32 flush_on_fsync;
501 	bool ext_addr;
502 	struct platform_device  *pdev;
503 	const struct xilinx_dma_config *dma_config;
504 	struct clk *axi_clk;
505 	struct clk *tx_clk;
506 	struct clk *txs_clk;
507 	struct clk *rx_clk;
508 	struct clk *rxs_clk;
509 	u32 s2mm_chan_id;
510 	u32 mm2s_chan_id;
511 	u32 max_buffer_len;
512 };
513 
514 /* Macros */
515 #define to_xilinx_chan(chan) \
516 	container_of(chan, struct xilinx_dma_chan, common)
517 #define to_dma_tx_descriptor(tx) \
518 	container_of(tx, struct xilinx_dma_tx_descriptor, async_tx)
519 #define xilinx_dma_poll_timeout(chan, reg, val, cond, delay_us, timeout_us) \
520 	readl_poll_timeout(chan->xdev->regs + chan->ctrl_offset + reg, val, \
521 			   cond, delay_us, timeout_us)
522 
523 /* IO accessors */
524 static inline u32 dma_read(struct xilinx_dma_chan *chan, u32 reg)
525 {
526 	return ioread32(chan->xdev->regs + reg);
527 }
528 
529 static inline void dma_write(struct xilinx_dma_chan *chan, u32 reg, u32 value)
530 {
531 	iowrite32(value, chan->xdev->regs + reg);
532 }
533 
534 static inline void vdma_desc_write(struct xilinx_dma_chan *chan, u32 reg,
535 				   u32 value)
536 {
537 	dma_write(chan, chan->desc_offset + reg, value);
538 }
539 
540 static inline u32 dma_ctrl_read(struct xilinx_dma_chan *chan, u32 reg)
541 {
542 	return dma_read(chan, chan->ctrl_offset + reg);
543 }
544 
545 static inline void dma_ctrl_write(struct xilinx_dma_chan *chan, u32 reg,
546 				   u32 value)
547 {
548 	dma_write(chan, chan->ctrl_offset + reg, value);
549 }
550 
551 static inline void dma_ctrl_clr(struct xilinx_dma_chan *chan, u32 reg,
552 				 u32 clr)
553 {
554 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) & ~clr);
555 }
556 
557 static inline void dma_ctrl_set(struct xilinx_dma_chan *chan, u32 reg,
558 				 u32 set)
559 {
560 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) | set);
561 }
562 
563 /**
564  * vdma_desc_write_64 - 64-bit descriptor write
565  * @chan: Driver specific VDMA channel
566  * @reg: Register to write
567  * @value_lsb: lower address of the descriptor.
568  * @value_msb: upper address of the descriptor.
569  *
570  * Since vdma driver is trying to write to a register offset which is not a
571  * multiple of 64 bits(ex : 0x5c), we are writing as two separate 32 bits
572  * instead of a single 64 bit register write.
573  */
574 static inline void vdma_desc_write_64(struct xilinx_dma_chan *chan, u32 reg,
575 				      u32 value_lsb, u32 value_msb)
576 {
577 	/* Write the lsb 32 bits*/
578 	writel(value_lsb, chan->xdev->regs + chan->desc_offset + reg);
579 
580 	/* Write the msb 32 bits */
581 	writel(value_msb, chan->xdev->regs + chan->desc_offset + reg + 4);
582 }
583 
584 static inline void dma_writeq(struct xilinx_dma_chan *chan, u32 reg, u64 value)
585 {
586 	lo_hi_writeq(value, chan->xdev->regs + chan->ctrl_offset + reg);
587 }
588 
589 static inline void xilinx_write(struct xilinx_dma_chan *chan, u32 reg,
590 				dma_addr_t addr)
591 {
592 	if (chan->ext_addr)
593 		dma_writeq(chan, reg, addr);
594 	else
595 		dma_ctrl_write(chan, reg, addr);
596 }
597 
598 static inline void xilinx_axidma_buf(struct xilinx_dma_chan *chan,
599 				     struct xilinx_axidma_desc_hw *hw,
600 				     dma_addr_t buf_addr, size_t sg_used,
601 				     size_t period_len)
602 {
603 	if (chan->ext_addr) {
604 		hw->buf_addr = lower_32_bits(buf_addr + sg_used + period_len);
605 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used +
606 						 period_len);
607 	} else {
608 		hw->buf_addr = buf_addr + sg_used + period_len;
609 	}
610 }
611 
612 static inline void xilinx_aximcdma_buf(struct xilinx_dma_chan *chan,
613 				       struct xilinx_aximcdma_desc_hw *hw,
614 				       dma_addr_t buf_addr, size_t sg_used)
615 {
616 	if (chan->ext_addr) {
617 		hw->buf_addr = lower_32_bits(buf_addr + sg_used);
618 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used);
619 	} else {
620 		hw->buf_addr = buf_addr + sg_used;
621 	}
622 }
623 
624 /* -----------------------------------------------------------------------------
625  * Descriptors and segments alloc and free
626  */
627 
628 /**
629  * xilinx_vdma_alloc_tx_segment - Allocate transaction segment
630  * @chan: Driver specific DMA channel
631  *
632  * Return: The allocated segment on success and NULL on failure.
633  */
634 static struct xilinx_vdma_tx_segment *
635 xilinx_vdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
636 {
637 	struct xilinx_vdma_tx_segment *segment;
638 	dma_addr_t phys;
639 
640 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
641 	if (!segment)
642 		return NULL;
643 
644 	segment->phys = phys;
645 
646 	return segment;
647 }
648 
649 /**
650  * xilinx_cdma_alloc_tx_segment - Allocate transaction segment
651  * @chan: Driver specific DMA channel
652  *
653  * Return: The allocated segment on success and NULL on failure.
654  */
655 static struct xilinx_cdma_tx_segment *
656 xilinx_cdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
657 {
658 	struct xilinx_cdma_tx_segment *segment;
659 	dma_addr_t phys;
660 
661 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
662 	if (!segment)
663 		return NULL;
664 
665 	segment->phys = phys;
666 
667 	return segment;
668 }
669 
670 /**
671  * xilinx_axidma_alloc_tx_segment - Allocate transaction segment
672  * @chan: Driver specific DMA channel
673  *
674  * Return: The allocated segment on success and NULL on failure.
675  */
676 static struct xilinx_axidma_tx_segment *
677 xilinx_axidma_alloc_tx_segment(struct xilinx_dma_chan *chan)
678 {
679 	struct xilinx_axidma_tx_segment *segment = NULL;
680 	unsigned long flags;
681 
682 	spin_lock_irqsave(&chan->lock, flags);
683 	if (!list_empty(&chan->free_seg_list)) {
684 		segment = list_first_entry(&chan->free_seg_list,
685 					   struct xilinx_axidma_tx_segment,
686 					   node);
687 		list_del(&segment->node);
688 	}
689 	spin_unlock_irqrestore(&chan->lock, flags);
690 
691 	if (!segment)
692 		dev_dbg(chan->dev, "Could not find free tx segment\n");
693 
694 	return segment;
695 }
696 
697 /**
698  * xilinx_aximcdma_alloc_tx_segment - Allocate transaction segment
699  * @chan: Driver specific DMA channel
700  *
701  * Return: The allocated segment on success and NULL on failure.
702  */
703 static struct xilinx_aximcdma_tx_segment *
704 xilinx_aximcdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
705 {
706 	struct xilinx_aximcdma_tx_segment *segment = NULL;
707 	unsigned long flags;
708 
709 	spin_lock_irqsave(&chan->lock, flags);
710 	if (!list_empty(&chan->free_seg_list)) {
711 		segment = list_first_entry(&chan->free_seg_list,
712 					   struct xilinx_aximcdma_tx_segment,
713 					   node);
714 		list_del(&segment->node);
715 	}
716 	spin_unlock_irqrestore(&chan->lock, flags);
717 
718 	return segment;
719 }
720 
721 static void xilinx_dma_clean_hw_desc(struct xilinx_axidma_desc_hw *hw)
722 {
723 	u32 next_desc = hw->next_desc;
724 	u32 next_desc_msb = hw->next_desc_msb;
725 
726 	memset(hw, 0, sizeof(struct xilinx_axidma_desc_hw));
727 
728 	hw->next_desc = next_desc;
729 	hw->next_desc_msb = next_desc_msb;
730 }
731 
732 static void xilinx_mcdma_clean_hw_desc(struct xilinx_aximcdma_desc_hw *hw)
733 {
734 	u32 next_desc = hw->next_desc;
735 	u32 next_desc_msb = hw->next_desc_msb;
736 
737 	memset(hw, 0, sizeof(struct xilinx_aximcdma_desc_hw));
738 
739 	hw->next_desc = next_desc;
740 	hw->next_desc_msb = next_desc_msb;
741 }
742 
743 /**
744  * xilinx_dma_free_tx_segment - Free transaction segment
745  * @chan: Driver specific DMA channel
746  * @segment: DMA transaction segment
747  */
748 static void xilinx_dma_free_tx_segment(struct xilinx_dma_chan *chan,
749 				struct xilinx_axidma_tx_segment *segment)
750 {
751 	xilinx_dma_clean_hw_desc(&segment->hw);
752 
753 	list_add_tail(&segment->node, &chan->free_seg_list);
754 }
755 
756 /**
757  * xilinx_mcdma_free_tx_segment - Free transaction segment
758  * @chan: Driver specific DMA channel
759  * @segment: DMA transaction segment
760  */
761 static void xilinx_mcdma_free_tx_segment(struct xilinx_dma_chan *chan,
762 					 struct xilinx_aximcdma_tx_segment *
763 					 segment)
764 {
765 	xilinx_mcdma_clean_hw_desc(&segment->hw);
766 
767 	list_add_tail(&segment->node, &chan->free_seg_list);
768 }
769 
770 /**
771  * xilinx_cdma_free_tx_segment - Free transaction segment
772  * @chan: Driver specific DMA channel
773  * @segment: DMA transaction segment
774  */
775 static void xilinx_cdma_free_tx_segment(struct xilinx_dma_chan *chan,
776 				struct xilinx_cdma_tx_segment *segment)
777 {
778 	dma_pool_free(chan->desc_pool, segment, segment->phys);
779 }
780 
781 /**
782  * xilinx_vdma_free_tx_segment - Free transaction segment
783  * @chan: Driver specific DMA channel
784  * @segment: DMA transaction segment
785  */
786 static void xilinx_vdma_free_tx_segment(struct xilinx_dma_chan *chan,
787 					struct xilinx_vdma_tx_segment *segment)
788 {
789 	dma_pool_free(chan->desc_pool, segment, segment->phys);
790 }
791 
792 /**
793  * xilinx_dma_tx_descriptor - Allocate transaction descriptor
794  * @chan: Driver specific DMA channel
795  *
796  * Return: The allocated descriptor on success and NULL on failure.
797  */
798 static struct xilinx_dma_tx_descriptor *
799 xilinx_dma_alloc_tx_descriptor(struct xilinx_dma_chan *chan)
800 {
801 	struct xilinx_dma_tx_descriptor *desc;
802 
803 	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
804 	if (!desc)
805 		return NULL;
806 
807 	INIT_LIST_HEAD(&desc->segments);
808 
809 	return desc;
810 }
811 
812 /**
813  * xilinx_dma_free_tx_descriptor - Free transaction descriptor
814  * @chan: Driver specific DMA channel
815  * @desc: DMA transaction descriptor
816  */
817 static void
818 xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
819 			       struct xilinx_dma_tx_descriptor *desc)
820 {
821 	struct xilinx_vdma_tx_segment *segment, *next;
822 	struct xilinx_cdma_tx_segment *cdma_segment, *cdma_next;
823 	struct xilinx_axidma_tx_segment *axidma_segment, *axidma_next;
824 	struct xilinx_aximcdma_tx_segment *aximcdma_segment, *aximcdma_next;
825 
826 	if (!desc)
827 		return;
828 
829 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
830 		list_for_each_entry_safe(segment, next, &desc->segments, node) {
831 			list_del(&segment->node);
832 			xilinx_vdma_free_tx_segment(chan, segment);
833 		}
834 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
835 		list_for_each_entry_safe(cdma_segment, cdma_next,
836 					 &desc->segments, node) {
837 			list_del(&cdma_segment->node);
838 			xilinx_cdma_free_tx_segment(chan, cdma_segment);
839 		}
840 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
841 		list_for_each_entry_safe(axidma_segment, axidma_next,
842 					 &desc->segments, node) {
843 			list_del(&axidma_segment->node);
844 			xilinx_dma_free_tx_segment(chan, axidma_segment);
845 		}
846 	} else {
847 		list_for_each_entry_safe(aximcdma_segment, aximcdma_next,
848 					 &desc->segments, node) {
849 			list_del(&aximcdma_segment->node);
850 			xilinx_mcdma_free_tx_segment(chan, aximcdma_segment);
851 		}
852 	}
853 
854 	kfree(desc);
855 }
856 
857 /* Required functions */
858 
859 /**
860  * xilinx_dma_free_desc_list - Free descriptors list
861  * @chan: Driver specific DMA channel
862  * @list: List to parse and delete the descriptor
863  */
864 static void xilinx_dma_free_desc_list(struct xilinx_dma_chan *chan,
865 					struct list_head *list)
866 {
867 	struct xilinx_dma_tx_descriptor *desc, *next;
868 
869 	list_for_each_entry_safe(desc, next, list, node) {
870 		list_del(&desc->node);
871 		xilinx_dma_free_tx_descriptor(chan, desc);
872 	}
873 }
874 
875 /**
876  * xilinx_dma_free_descriptors - Free channel descriptors
877  * @chan: Driver specific DMA channel
878  */
879 static void xilinx_dma_free_descriptors(struct xilinx_dma_chan *chan)
880 {
881 	unsigned long flags;
882 
883 	spin_lock_irqsave(&chan->lock, flags);
884 
885 	xilinx_dma_free_desc_list(chan, &chan->pending_list);
886 	xilinx_dma_free_desc_list(chan, &chan->done_list);
887 	xilinx_dma_free_desc_list(chan, &chan->active_list);
888 
889 	spin_unlock_irqrestore(&chan->lock, flags);
890 }
891 
892 /**
893  * xilinx_dma_free_chan_resources - Free channel resources
894  * @dchan: DMA channel
895  */
896 static void xilinx_dma_free_chan_resources(struct dma_chan *dchan)
897 {
898 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
899 	unsigned long flags;
900 
901 	dev_dbg(chan->dev, "Free all channel resources.\n");
902 
903 	xilinx_dma_free_descriptors(chan);
904 
905 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
906 		spin_lock_irqsave(&chan->lock, flags);
907 		INIT_LIST_HEAD(&chan->free_seg_list);
908 		spin_unlock_irqrestore(&chan->lock, flags);
909 
910 		/* Free memory that is allocated for BD */
911 		dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
912 				  XILINX_DMA_NUM_DESCS, chan->seg_v,
913 				  chan->seg_p);
914 
915 		/* Free Memory that is allocated for cyclic DMA Mode */
916 		dma_free_coherent(chan->dev, sizeof(*chan->cyclic_seg_v),
917 				  chan->cyclic_seg_v, chan->cyclic_seg_p);
918 	}
919 
920 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
921 		spin_lock_irqsave(&chan->lock, flags);
922 		INIT_LIST_HEAD(&chan->free_seg_list);
923 		spin_unlock_irqrestore(&chan->lock, flags);
924 
925 		/* Free memory that is allocated for BD */
926 		dma_free_coherent(chan->dev, sizeof(*chan->seg_mv) *
927 				  XILINX_DMA_NUM_DESCS, chan->seg_mv,
928 				  chan->seg_p);
929 	}
930 
931 	if (chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA &&
932 	    chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA) {
933 		dma_pool_destroy(chan->desc_pool);
934 		chan->desc_pool = NULL;
935 	}
936 
937 }
938 
939 /**
940  * xilinx_dma_get_residue - Compute residue for a given descriptor
941  * @chan: Driver specific dma channel
942  * @desc: dma transaction descriptor
943  *
944  * Return: The number of residue bytes for the descriptor.
945  */
946 static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
947 				  struct xilinx_dma_tx_descriptor *desc)
948 {
949 	struct xilinx_cdma_tx_segment *cdma_seg;
950 	struct xilinx_axidma_tx_segment *axidma_seg;
951 	struct xilinx_cdma_desc_hw *cdma_hw;
952 	struct xilinx_axidma_desc_hw *axidma_hw;
953 	struct list_head *entry;
954 	u32 residue = 0;
955 
956 	list_for_each(entry, &desc->segments) {
957 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
958 			cdma_seg = list_entry(entry,
959 					      struct xilinx_cdma_tx_segment,
960 					      node);
961 			cdma_hw = &cdma_seg->hw;
962 			residue += (cdma_hw->control - cdma_hw->status) &
963 				   chan->xdev->max_buffer_len;
964 		} else {
965 			axidma_seg = list_entry(entry,
966 						struct xilinx_axidma_tx_segment,
967 						node);
968 			axidma_hw = &axidma_seg->hw;
969 			residue += (axidma_hw->control - axidma_hw->status) &
970 				   chan->xdev->max_buffer_len;
971 		}
972 	}
973 
974 	return residue;
975 }
976 
977 /**
978  * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
979  * @chan: Driver specific dma channel
980  * @desc: dma transaction descriptor
981  * @flags: flags for spin lock
982  */
983 static void xilinx_dma_chan_handle_cyclic(struct xilinx_dma_chan *chan,
984 					  struct xilinx_dma_tx_descriptor *desc,
985 					  unsigned long *flags)
986 {
987 	dma_async_tx_callback callback;
988 	void *callback_param;
989 
990 	callback = desc->async_tx.callback;
991 	callback_param = desc->async_tx.callback_param;
992 	if (callback) {
993 		spin_unlock_irqrestore(&chan->lock, *flags);
994 		callback(callback_param);
995 		spin_lock_irqsave(&chan->lock, *flags);
996 	}
997 }
998 
999 /**
1000  * xilinx_dma_chan_desc_cleanup - Clean channel descriptors
1001  * @chan: Driver specific DMA channel
1002  */
1003 static void xilinx_dma_chan_desc_cleanup(struct xilinx_dma_chan *chan)
1004 {
1005 	struct xilinx_dma_tx_descriptor *desc, *next;
1006 	unsigned long flags;
1007 
1008 	spin_lock_irqsave(&chan->lock, flags);
1009 
1010 	list_for_each_entry_safe(desc, next, &chan->done_list, node) {
1011 		struct dmaengine_result result;
1012 
1013 		if (desc->cyclic) {
1014 			xilinx_dma_chan_handle_cyclic(chan, desc, &flags);
1015 			break;
1016 		}
1017 
1018 		/* Remove from the list of running transactions */
1019 		list_del(&desc->node);
1020 
1021 		if (unlikely(desc->err)) {
1022 			if (chan->direction == DMA_DEV_TO_MEM)
1023 				result.result = DMA_TRANS_READ_FAILED;
1024 			else
1025 				result.result = DMA_TRANS_WRITE_FAILED;
1026 		} else {
1027 			result.result = DMA_TRANS_NOERROR;
1028 		}
1029 
1030 		result.residue = desc->residue;
1031 
1032 		/* Run the link descriptor callback function */
1033 		spin_unlock_irqrestore(&chan->lock, flags);
1034 		dmaengine_desc_get_callback_invoke(&desc->async_tx, &result);
1035 		spin_lock_irqsave(&chan->lock, flags);
1036 
1037 		/* Run any dependencies, then free the descriptor */
1038 		dma_run_dependencies(&desc->async_tx);
1039 		xilinx_dma_free_tx_descriptor(chan, desc);
1040 	}
1041 
1042 	spin_unlock_irqrestore(&chan->lock, flags);
1043 }
1044 
1045 /**
1046  * xilinx_dma_do_tasklet - Schedule completion tasklet
1047  * @data: Pointer to the Xilinx DMA channel structure
1048  */
1049 static void xilinx_dma_do_tasklet(unsigned long data)
1050 {
1051 	struct xilinx_dma_chan *chan = (struct xilinx_dma_chan *)data;
1052 
1053 	xilinx_dma_chan_desc_cleanup(chan);
1054 }
1055 
1056 /**
1057  * xilinx_dma_alloc_chan_resources - Allocate channel resources
1058  * @dchan: DMA channel
1059  *
1060  * Return: '0' on success and failure value on error
1061  */
1062 static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
1063 {
1064 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1065 	int i;
1066 
1067 	/* Has this channel already been allocated? */
1068 	if (chan->desc_pool)
1069 		return 0;
1070 
1071 	/*
1072 	 * We need the descriptor to be aligned to 64bytes
1073 	 * for meeting Xilinx VDMA specification requirement.
1074 	 */
1075 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1076 		/* Allocate the buffer descriptors. */
1077 		chan->seg_v = dma_alloc_coherent(chan->dev,
1078 						 sizeof(*chan->seg_v) * XILINX_DMA_NUM_DESCS,
1079 						 &chan->seg_p, GFP_KERNEL);
1080 		if (!chan->seg_v) {
1081 			dev_err(chan->dev,
1082 				"unable to allocate channel %d descriptors\n",
1083 				chan->id);
1084 			return -ENOMEM;
1085 		}
1086 		/*
1087 		 * For cyclic DMA mode we need to program the tail Descriptor
1088 		 * register with a value which is not a part of the BD chain
1089 		 * so allocating a desc segment during channel allocation for
1090 		 * programming tail descriptor.
1091 		 */
1092 		chan->cyclic_seg_v = dma_alloc_coherent(chan->dev,
1093 							sizeof(*chan->cyclic_seg_v),
1094 							&chan->cyclic_seg_p,
1095 							GFP_KERNEL);
1096 		if (!chan->cyclic_seg_v) {
1097 			dev_err(chan->dev,
1098 				"unable to allocate desc segment for cyclic DMA\n");
1099 			dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
1100 				XILINX_DMA_NUM_DESCS, chan->seg_v,
1101 				chan->seg_p);
1102 			return -ENOMEM;
1103 		}
1104 		chan->cyclic_seg_v->phys = chan->cyclic_seg_p;
1105 
1106 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1107 			chan->seg_v[i].hw.next_desc =
1108 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1109 				((i + 1) % XILINX_DMA_NUM_DESCS));
1110 			chan->seg_v[i].hw.next_desc_msb =
1111 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1112 				((i + 1) % XILINX_DMA_NUM_DESCS));
1113 			chan->seg_v[i].phys = chan->seg_p +
1114 				sizeof(*chan->seg_v) * i;
1115 			list_add_tail(&chan->seg_v[i].node,
1116 				      &chan->free_seg_list);
1117 		}
1118 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
1119 		/* Allocate the buffer descriptors. */
1120 		chan->seg_mv = dma_alloc_coherent(chan->dev,
1121 						  sizeof(*chan->seg_mv) *
1122 						  XILINX_DMA_NUM_DESCS,
1123 						  &chan->seg_p, GFP_KERNEL);
1124 		if (!chan->seg_mv) {
1125 			dev_err(chan->dev,
1126 				"unable to allocate channel %d descriptors\n",
1127 				chan->id);
1128 			return -ENOMEM;
1129 		}
1130 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1131 			chan->seg_mv[i].hw.next_desc =
1132 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1133 				((i + 1) % XILINX_DMA_NUM_DESCS));
1134 			chan->seg_mv[i].hw.next_desc_msb =
1135 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1136 				((i + 1) % XILINX_DMA_NUM_DESCS));
1137 			chan->seg_mv[i].phys = chan->seg_p +
1138 				sizeof(*chan->seg_v) * i;
1139 			list_add_tail(&chan->seg_mv[i].node,
1140 				      &chan->free_seg_list);
1141 		}
1142 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1143 		chan->desc_pool = dma_pool_create("xilinx_cdma_desc_pool",
1144 				   chan->dev,
1145 				   sizeof(struct xilinx_cdma_tx_segment),
1146 				   __alignof__(struct xilinx_cdma_tx_segment),
1147 				   0);
1148 	} else {
1149 		chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
1150 				     chan->dev,
1151 				     sizeof(struct xilinx_vdma_tx_segment),
1152 				     __alignof__(struct xilinx_vdma_tx_segment),
1153 				     0);
1154 	}
1155 
1156 	if (!chan->desc_pool &&
1157 	    ((chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA) &&
1158 		chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA)) {
1159 		dev_err(chan->dev,
1160 			"unable to allocate channel %d descriptor pool\n",
1161 			chan->id);
1162 		return -ENOMEM;
1163 	}
1164 
1165 	dma_cookie_init(dchan);
1166 
1167 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1168 		/* For AXI DMA resetting once channel will reset the
1169 		 * other channel as well so enable the interrupts here.
1170 		 */
1171 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1172 			      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1173 	}
1174 
1175 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
1176 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1177 			     XILINX_CDMA_CR_SGMODE);
1178 
1179 	return 0;
1180 }
1181 
1182 /**
1183  * xilinx_dma_calc_copysize - Calculate the amount of data to copy
1184  * @chan: Driver specific DMA channel
1185  * @size: Total data that needs to be copied
1186  * @done: Amount of data that has been already copied
1187  *
1188  * Return: Amount of data that has to be copied
1189  */
1190 static int xilinx_dma_calc_copysize(struct xilinx_dma_chan *chan,
1191 				    int size, int done)
1192 {
1193 	size_t copy;
1194 
1195 	copy = min_t(size_t, size - done,
1196 		     chan->xdev->max_buffer_len);
1197 
1198 	if ((copy + done < size) &&
1199 	    chan->xdev->common.copy_align) {
1200 		/*
1201 		 * If this is not the last descriptor, make sure
1202 		 * the next one will be properly aligned
1203 		 */
1204 		copy = rounddown(copy,
1205 				 (1 << chan->xdev->common.copy_align));
1206 	}
1207 	return copy;
1208 }
1209 
1210 /**
1211  * xilinx_dma_tx_status - Get DMA transaction status
1212  * @dchan: DMA channel
1213  * @cookie: Transaction identifier
1214  * @txstate: Transaction state
1215  *
1216  * Return: DMA transaction status
1217  */
1218 static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
1219 					dma_cookie_t cookie,
1220 					struct dma_tx_state *txstate)
1221 {
1222 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1223 	struct xilinx_dma_tx_descriptor *desc;
1224 	enum dma_status ret;
1225 	unsigned long flags;
1226 	u32 residue = 0;
1227 
1228 	ret = dma_cookie_status(dchan, cookie, txstate);
1229 	if (ret == DMA_COMPLETE || !txstate)
1230 		return ret;
1231 
1232 	spin_lock_irqsave(&chan->lock, flags);
1233 
1234 	desc = list_last_entry(&chan->active_list,
1235 			       struct xilinx_dma_tx_descriptor, node);
1236 	/*
1237 	 * VDMA and simple mode do not support residue reporting, so the
1238 	 * residue field will always be 0.
1239 	 */
1240 	if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA)
1241 		residue = xilinx_dma_get_residue(chan, desc);
1242 
1243 	spin_unlock_irqrestore(&chan->lock, flags);
1244 
1245 	dma_set_residue(txstate, residue);
1246 
1247 	return ret;
1248 }
1249 
1250 /**
1251  * xilinx_dma_stop_transfer - Halt DMA channel
1252  * @chan: Driver specific DMA channel
1253  *
1254  * Return: '0' on success and failure value on error
1255  */
1256 static int xilinx_dma_stop_transfer(struct xilinx_dma_chan *chan)
1257 {
1258 	u32 val;
1259 
1260 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1261 
1262 	/* Wait for the hardware to halt */
1263 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1264 				       val & XILINX_DMA_DMASR_HALTED, 0,
1265 				       XILINX_DMA_LOOP_COUNT);
1266 }
1267 
1268 /**
1269  * xilinx_cdma_stop_transfer - Wait for the current transfer to complete
1270  * @chan: Driver specific DMA channel
1271  *
1272  * Return: '0' on success and failure value on error
1273  */
1274 static int xilinx_cdma_stop_transfer(struct xilinx_dma_chan *chan)
1275 {
1276 	u32 val;
1277 
1278 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1279 				       val & XILINX_DMA_DMASR_IDLE, 0,
1280 				       XILINX_DMA_LOOP_COUNT);
1281 }
1282 
1283 /**
1284  * xilinx_dma_start - Start DMA channel
1285  * @chan: Driver specific DMA channel
1286  */
1287 static void xilinx_dma_start(struct xilinx_dma_chan *chan)
1288 {
1289 	int err;
1290 	u32 val;
1291 
1292 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1293 
1294 	/* Wait for the hardware to start */
1295 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1296 				      !(val & XILINX_DMA_DMASR_HALTED), 0,
1297 				      XILINX_DMA_LOOP_COUNT);
1298 
1299 	if (err) {
1300 		dev_err(chan->dev, "Cannot start channel %p: %x\n",
1301 			chan, dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1302 
1303 		chan->err = true;
1304 	}
1305 }
1306 
1307 /**
1308  * xilinx_vdma_start_transfer - Starts VDMA transfer
1309  * @chan: Driver specific channel struct pointer
1310  */
1311 static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
1312 {
1313 	struct xilinx_vdma_config *config = &chan->config;
1314 	struct xilinx_dma_tx_descriptor *desc;
1315 	u32 reg, j;
1316 	struct xilinx_vdma_tx_segment *segment, *last = NULL;
1317 	int i = 0;
1318 
1319 	/* This function was invoked with lock held */
1320 	if (chan->err)
1321 		return;
1322 
1323 	if (!chan->idle)
1324 		return;
1325 
1326 	if (list_empty(&chan->pending_list))
1327 		return;
1328 
1329 	desc = list_first_entry(&chan->pending_list,
1330 				struct xilinx_dma_tx_descriptor, node);
1331 
1332 	/* Configure the hardware using info in the config structure */
1333 	if (chan->has_vflip) {
1334 		reg = dma_read(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP);
1335 		reg &= ~XILINX_VDMA_ENABLE_VERTICAL_FLIP;
1336 		reg |= config->vflip_en;
1337 		dma_write(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP,
1338 			  reg);
1339 	}
1340 
1341 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1342 
1343 	if (config->frm_cnt_en)
1344 		reg |= XILINX_DMA_DMACR_FRAMECNT_EN;
1345 	else
1346 		reg &= ~XILINX_DMA_DMACR_FRAMECNT_EN;
1347 
1348 	/* If not parking, enable circular mode */
1349 	if (config->park)
1350 		reg &= ~XILINX_DMA_DMACR_CIRC_EN;
1351 	else
1352 		reg |= XILINX_DMA_DMACR_CIRC_EN;
1353 
1354 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1355 
1356 	j = chan->desc_submitcount;
1357 	reg = dma_read(chan, XILINX_DMA_REG_PARK_PTR);
1358 	if (chan->direction == DMA_MEM_TO_DEV) {
1359 		reg &= ~XILINX_DMA_PARK_PTR_RD_REF_MASK;
1360 		reg |= j << XILINX_DMA_PARK_PTR_RD_REF_SHIFT;
1361 	} else {
1362 		reg &= ~XILINX_DMA_PARK_PTR_WR_REF_MASK;
1363 		reg |= j << XILINX_DMA_PARK_PTR_WR_REF_SHIFT;
1364 	}
1365 	dma_write(chan, XILINX_DMA_REG_PARK_PTR, reg);
1366 
1367 	/* Start the hardware */
1368 	xilinx_dma_start(chan);
1369 
1370 	if (chan->err)
1371 		return;
1372 
1373 	/* Start the transfer */
1374 	if (chan->desc_submitcount < chan->num_frms)
1375 		i = chan->desc_submitcount;
1376 
1377 	list_for_each_entry(segment, &desc->segments, node) {
1378 		if (chan->ext_addr)
1379 			vdma_desc_write_64(chan,
1380 				   XILINX_VDMA_REG_START_ADDRESS_64(i++),
1381 				   segment->hw.buf_addr,
1382 				   segment->hw.buf_addr_msb);
1383 		else
1384 			vdma_desc_write(chan,
1385 					XILINX_VDMA_REG_START_ADDRESS(i++),
1386 					segment->hw.buf_addr);
1387 
1388 		last = segment;
1389 	}
1390 
1391 	if (!last)
1392 		return;
1393 
1394 	/* HW expects these parameters to be same for one transaction */
1395 	vdma_desc_write(chan, XILINX_DMA_REG_HSIZE, last->hw.hsize);
1396 	vdma_desc_write(chan, XILINX_DMA_REG_FRMDLY_STRIDE,
1397 			last->hw.stride);
1398 	vdma_desc_write(chan, XILINX_DMA_REG_VSIZE, last->hw.vsize);
1399 
1400 	chan->desc_submitcount++;
1401 	chan->desc_pendingcount--;
1402 	list_del(&desc->node);
1403 	list_add_tail(&desc->node, &chan->active_list);
1404 	if (chan->desc_submitcount == chan->num_frms)
1405 		chan->desc_submitcount = 0;
1406 
1407 	chan->idle = false;
1408 }
1409 
1410 /**
1411  * xilinx_cdma_start_transfer - Starts cdma transfer
1412  * @chan: Driver specific channel struct pointer
1413  */
1414 static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
1415 {
1416 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1417 	struct xilinx_cdma_tx_segment *tail_segment;
1418 	u32 ctrl_reg = dma_read(chan, XILINX_DMA_REG_DMACR);
1419 
1420 	if (chan->err)
1421 		return;
1422 
1423 	if (!chan->idle)
1424 		return;
1425 
1426 	if (list_empty(&chan->pending_list))
1427 		return;
1428 
1429 	head_desc = list_first_entry(&chan->pending_list,
1430 				     struct xilinx_dma_tx_descriptor, node);
1431 	tail_desc = list_last_entry(&chan->pending_list,
1432 				    struct xilinx_dma_tx_descriptor, node);
1433 	tail_segment = list_last_entry(&tail_desc->segments,
1434 				       struct xilinx_cdma_tx_segment, node);
1435 
1436 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1437 		ctrl_reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1438 		ctrl_reg |= chan->desc_pendingcount <<
1439 				XILINX_DMA_CR_COALESCE_SHIFT;
1440 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, ctrl_reg);
1441 	}
1442 
1443 	if (chan->has_sg) {
1444 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
1445 			     XILINX_CDMA_CR_SGMODE);
1446 
1447 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1448 			     XILINX_CDMA_CR_SGMODE);
1449 
1450 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1451 			     head_desc->async_tx.phys);
1452 
1453 		/* Update tail ptr register which will start the transfer */
1454 		xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1455 			     tail_segment->phys);
1456 	} else {
1457 		/* In simple mode */
1458 		struct xilinx_cdma_tx_segment *segment;
1459 		struct xilinx_cdma_desc_hw *hw;
1460 
1461 		segment = list_first_entry(&head_desc->segments,
1462 					   struct xilinx_cdma_tx_segment,
1463 					   node);
1464 
1465 		hw = &segment->hw;
1466 
1467 		xilinx_write(chan, XILINX_CDMA_REG_SRCADDR,
1468 			     xilinx_prep_dma_addr_t(hw->src_addr));
1469 		xilinx_write(chan, XILINX_CDMA_REG_DSTADDR,
1470 			     xilinx_prep_dma_addr_t(hw->dest_addr));
1471 
1472 		/* Start the transfer */
1473 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1474 				hw->control & chan->xdev->max_buffer_len);
1475 	}
1476 
1477 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1478 	chan->desc_pendingcount = 0;
1479 	chan->idle = false;
1480 }
1481 
1482 /**
1483  * xilinx_dma_start_transfer - Starts DMA transfer
1484  * @chan: Driver specific channel struct pointer
1485  */
1486 static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
1487 {
1488 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1489 	struct xilinx_axidma_tx_segment *tail_segment;
1490 	u32 reg;
1491 
1492 	if (chan->err)
1493 		return;
1494 
1495 	if (list_empty(&chan->pending_list))
1496 		return;
1497 
1498 	if (!chan->idle)
1499 		return;
1500 
1501 	head_desc = list_first_entry(&chan->pending_list,
1502 				     struct xilinx_dma_tx_descriptor, node);
1503 	tail_desc = list_last_entry(&chan->pending_list,
1504 				    struct xilinx_dma_tx_descriptor, node);
1505 	tail_segment = list_last_entry(&tail_desc->segments,
1506 				       struct xilinx_axidma_tx_segment, node);
1507 
1508 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1509 
1510 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1511 		reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1512 		reg |= chan->desc_pendingcount <<
1513 				  XILINX_DMA_CR_COALESCE_SHIFT;
1514 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1515 	}
1516 
1517 	if (chan->has_sg)
1518 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1519 			     head_desc->async_tx.phys);
1520 
1521 	xilinx_dma_start(chan);
1522 
1523 	if (chan->err)
1524 		return;
1525 
1526 	/* Start the transfer */
1527 	if (chan->has_sg) {
1528 		if (chan->cyclic)
1529 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1530 				     chan->cyclic_seg_v->phys);
1531 		else
1532 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1533 				     tail_segment->phys);
1534 	} else {
1535 		struct xilinx_axidma_tx_segment *segment;
1536 		struct xilinx_axidma_desc_hw *hw;
1537 
1538 		segment = list_first_entry(&head_desc->segments,
1539 					   struct xilinx_axidma_tx_segment,
1540 					   node);
1541 		hw = &segment->hw;
1542 
1543 		xilinx_write(chan, XILINX_DMA_REG_SRCDSTADDR,
1544 			     xilinx_prep_dma_addr_t(hw->buf_addr));
1545 
1546 		/* Start the transfer */
1547 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1548 			       hw->control & chan->xdev->max_buffer_len);
1549 	}
1550 
1551 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1552 	chan->desc_pendingcount = 0;
1553 	chan->idle = false;
1554 }
1555 
1556 /**
1557  * xilinx_mcdma_start_transfer - Starts MCDMA transfer
1558  * @chan: Driver specific channel struct pointer
1559  */
1560 static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan)
1561 {
1562 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1563 	struct xilinx_axidma_tx_segment *tail_segment;
1564 	u32 reg;
1565 
1566 	/*
1567 	 * lock has been held by calling functions, so we don't need it
1568 	 * to take it here again.
1569 	 */
1570 
1571 	if (chan->err)
1572 		return;
1573 
1574 	if (!chan->idle)
1575 		return;
1576 
1577 	if (list_empty(&chan->pending_list))
1578 		return;
1579 
1580 	head_desc = list_first_entry(&chan->pending_list,
1581 				     struct xilinx_dma_tx_descriptor, node);
1582 	tail_desc = list_last_entry(&chan->pending_list,
1583 				    struct xilinx_dma_tx_descriptor, node);
1584 	tail_segment = list_last_entry(&tail_desc->segments,
1585 				       struct xilinx_axidma_tx_segment, node);
1586 
1587 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1588 
1589 	if (chan->desc_pendingcount <= XILINX_MCDMA_COALESCE_MAX) {
1590 		reg &= ~XILINX_MCDMA_COALESCE_MASK;
1591 		reg |= chan->desc_pendingcount <<
1592 			XILINX_MCDMA_COALESCE_SHIFT;
1593 	}
1594 
1595 	reg |= XILINX_MCDMA_IRQ_ALL_MASK;
1596 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1597 
1598 	/* Program current descriptor */
1599 	xilinx_write(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET(chan->tdest),
1600 		     head_desc->async_tx.phys);
1601 
1602 	/* Program channel enable register */
1603 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHEN_OFFSET);
1604 	reg |= BIT(chan->tdest);
1605 	dma_ctrl_write(chan, XILINX_MCDMA_CHEN_OFFSET, reg);
1606 
1607 	/* Start the fetch of BDs for the channel */
1608 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1609 	reg |= XILINX_MCDMA_CR_RUNSTOP_MASK;
1610 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1611 
1612 	xilinx_dma_start(chan);
1613 
1614 	if (chan->err)
1615 		return;
1616 
1617 	/* Start the transfer */
1618 	xilinx_write(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET(chan->tdest),
1619 		     tail_segment->phys);
1620 
1621 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1622 	chan->desc_pendingcount = 0;
1623 	chan->idle = false;
1624 }
1625 
1626 /**
1627  * xilinx_dma_issue_pending - Issue pending transactions
1628  * @dchan: DMA channel
1629  */
1630 static void xilinx_dma_issue_pending(struct dma_chan *dchan)
1631 {
1632 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1633 	unsigned long flags;
1634 
1635 	spin_lock_irqsave(&chan->lock, flags);
1636 	chan->start_transfer(chan);
1637 	spin_unlock_irqrestore(&chan->lock, flags);
1638 }
1639 
1640 /**
1641  * xilinx_dma_complete_descriptor - Mark the active descriptor as complete
1642  * @chan : xilinx DMA channel
1643  *
1644  * CONTEXT: hardirq
1645  */
1646 static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
1647 {
1648 	struct xilinx_dma_tx_descriptor *desc, *next;
1649 
1650 	/* This function was invoked with lock held */
1651 	if (list_empty(&chan->active_list))
1652 		return;
1653 
1654 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
1655 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
1656 		    XDMA_TYPE_VDMA)
1657 			desc->residue = xilinx_dma_get_residue(chan, desc);
1658 		else
1659 			desc->residue = 0;
1660 		desc->err = chan->err;
1661 
1662 		list_del(&desc->node);
1663 		if (!desc->cyclic)
1664 			dma_cookie_complete(&desc->async_tx);
1665 		list_add_tail(&desc->node, &chan->done_list);
1666 	}
1667 }
1668 
1669 /**
1670  * xilinx_dma_reset - Reset DMA channel
1671  * @chan: Driver specific DMA channel
1672  *
1673  * Return: '0' on success and failure value on error
1674  */
1675 static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
1676 {
1677 	int err;
1678 	u32 tmp;
1679 
1680 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RESET);
1681 
1682 	/* Wait for the hardware to finish reset */
1683 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMACR, tmp,
1684 				      !(tmp & XILINX_DMA_DMACR_RESET), 0,
1685 				      XILINX_DMA_LOOP_COUNT);
1686 
1687 	if (err) {
1688 		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
1689 			dma_ctrl_read(chan, XILINX_DMA_REG_DMACR),
1690 			dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1691 		return -ETIMEDOUT;
1692 	}
1693 
1694 	chan->err = false;
1695 	chan->idle = true;
1696 	chan->desc_pendingcount = 0;
1697 	chan->desc_submitcount = 0;
1698 
1699 	return err;
1700 }
1701 
1702 /**
1703  * xilinx_dma_chan_reset - Reset DMA channel and enable interrupts
1704  * @chan: Driver specific DMA channel
1705  *
1706  * Return: '0' on success and failure value on error
1707  */
1708 static int xilinx_dma_chan_reset(struct xilinx_dma_chan *chan)
1709 {
1710 	int err;
1711 
1712 	/* Reset VDMA */
1713 	err = xilinx_dma_reset(chan);
1714 	if (err)
1715 		return err;
1716 
1717 	/* Enable interrupts */
1718 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1719 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1720 
1721 	return 0;
1722 }
1723 
1724 /**
1725  * xilinx_mcdma_irq_handler - MCDMA Interrupt handler
1726  * @irq: IRQ number
1727  * @data: Pointer to the Xilinx MCDMA channel structure
1728  *
1729  * Return: IRQ_HANDLED/IRQ_NONE
1730  */
1731 static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
1732 {
1733 	struct xilinx_dma_chan *chan = data;
1734 	u32 status, ser_offset, chan_sermask, chan_offset = 0, chan_id;
1735 
1736 	if (chan->direction == DMA_DEV_TO_MEM)
1737 		ser_offset = XILINX_MCDMA_RXINT_SER_OFFSET;
1738 	else
1739 		ser_offset = XILINX_MCDMA_TXINT_SER_OFFSET;
1740 
1741 	/* Read the channel id raising the interrupt*/
1742 	chan_sermask = dma_ctrl_read(chan, ser_offset);
1743 	chan_id = ffs(chan_sermask);
1744 
1745 	if (!chan_id)
1746 		return IRQ_NONE;
1747 
1748 	if (chan->direction == DMA_DEV_TO_MEM)
1749 		chan_offset = chan->xdev->dma_config->max_channels / 2;
1750 
1751 	chan_offset = chan_offset + (chan_id - 1);
1752 	chan = chan->xdev->chan[chan_offset];
1753 	/* Read the status and ack the interrupts. */
1754 	status = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest));
1755 	if (!(status & XILINX_MCDMA_IRQ_ALL_MASK))
1756 		return IRQ_NONE;
1757 
1758 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest),
1759 		       status & XILINX_MCDMA_IRQ_ALL_MASK);
1760 
1761 	if (status & XILINX_MCDMA_IRQ_ERR_MASK) {
1762 		dev_err(chan->dev, "Channel %p has errors %x cdr %x tdr %x\n",
1763 			chan,
1764 			dma_ctrl_read(chan, XILINX_MCDMA_CH_ERR_OFFSET),
1765 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET
1766 				      (chan->tdest)),
1767 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET
1768 				      (chan->tdest)));
1769 		chan->err = true;
1770 	}
1771 
1772 	if (status & XILINX_MCDMA_IRQ_DELAY_MASK) {
1773 		/*
1774 		 * Device takes too long to do the transfer when user requires
1775 		 * responsiveness.
1776 		 */
1777 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1778 	}
1779 
1780 	if (status & XILINX_MCDMA_IRQ_IOC_MASK) {
1781 		spin_lock(&chan->lock);
1782 		xilinx_dma_complete_descriptor(chan);
1783 		chan->idle = true;
1784 		chan->start_transfer(chan);
1785 		spin_unlock(&chan->lock);
1786 	}
1787 
1788 	tasklet_schedule(&chan->tasklet);
1789 	return IRQ_HANDLED;
1790 }
1791 
1792 /**
1793  * xilinx_dma_irq_handler - DMA Interrupt handler
1794  * @irq: IRQ number
1795  * @data: Pointer to the Xilinx DMA channel structure
1796  *
1797  * Return: IRQ_HANDLED/IRQ_NONE
1798  */
1799 static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
1800 {
1801 	struct xilinx_dma_chan *chan = data;
1802 	u32 status;
1803 
1804 	/* Read the status and ack the interrupts. */
1805 	status = dma_ctrl_read(chan, XILINX_DMA_REG_DMASR);
1806 	if (!(status & XILINX_DMA_DMAXR_ALL_IRQ_MASK))
1807 		return IRQ_NONE;
1808 
1809 	dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1810 			status & XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1811 
1812 	if (status & XILINX_DMA_DMASR_ERR_IRQ) {
1813 		/*
1814 		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
1815 		 * error is recoverable, ignore it. Otherwise flag the error.
1816 		 *
1817 		 * Only recoverable errors can be cleared in the DMASR register,
1818 		 * make sure not to write to other error bits to 1.
1819 		 */
1820 		u32 errors = status & XILINX_DMA_DMASR_ALL_ERR_MASK;
1821 
1822 		dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1823 				errors & XILINX_DMA_DMASR_ERR_RECOVER_MASK);
1824 
1825 		if (!chan->flush_on_fsync ||
1826 		    (errors & ~XILINX_DMA_DMASR_ERR_RECOVER_MASK)) {
1827 			dev_err(chan->dev,
1828 				"Channel %p has errors %x, cdr %x tdr %x\n",
1829 				chan, errors,
1830 				dma_ctrl_read(chan, XILINX_DMA_REG_CURDESC),
1831 				dma_ctrl_read(chan, XILINX_DMA_REG_TAILDESC));
1832 			chan->err = true;
1833 		}
1834 	}
1835 
1836 	if (status & XILINX_DMA_DMASR_DLY_CNT_IRQ) {
1837 		/*
1838 		 * Device takes too long to do the transfer when user requires
1839 		 * responsiveness.
1840 		 */
1841 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1842 	}
1843 
1844 	if (status & XILINX_DMA_DMASR_FRM_CNT_IRQ) {
1845 		spin_lock(&chan->lock);
1846 		xilinx_dma_complete_descriptor(chan);
1847 		chan->idle = true;
1848 		chan->start_transfer(chan);
1849 		spin_unlock(&chan->lock);
1850 	}
1851 
1852 	tasklet_schedule(&chan->tasklet);
1853 	return IRQ_HANDLED;
1854 }
1855 
1856 /**
1857  * append_desc_queue - Queuing descriptor
1858  * @chan: Driver specific dma channel
1859  * @desc: dma transaction descriptor
1860  */
1861 static void append_desc_queue(struct xilinx_dma_chan *chan,
1862 			      struct xilinx_dma_tx_descriptor *desc)
1863 {
1864 	struct xilinx_vdma_tx_segment *tail_segment;
1865 	struct xilinx_dma_tx_descriptor *tail_desc;
1866 	struct xilinx_axidma_tx_segment *axidma_tail_segment;
1867 	struct xilinx_cdma_tx_segment *cdma_tail_segment;
1868 
1869 	if (list_empty(&chan->pending_list))
1870 		goto append;
1871 
1872 	/*
1873 	 * Add the hardware descriptor to the chain of hardware descriptors
1874 	 * that already exists in memory.
1875 	 */
1876 	tail_desc = list_last_entry(&chan->pending_list,
1877 				    struct xilinx_dma_tx_descriptor, node);
1878 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
1879 		tail_segment = list_last_entry(&tail_desc->segments,
1880 					       struct xilinx_vdma_tx_segment,
1881 					       node);
1882 		tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1883 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1884 		cdma_tail_segment = list_last_entry(&tail_desc->segments,
1885 						struct xilinx_cdma_tx_segment,
1886 						node);
1887 		cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1888 	} else {
1889 		axidma_tail_segment = list_last_entry(&tail_desc->segments,
1890 					       struct xilinx_axidma_tx_segment,
1891 					       node);
1892 		axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1893 	}
1894 
1895 	/*
1896 	 * Add the software descriptor and all children to the list
1897 	 * of pending transactions
1898 	 */
1899 append:
1900 	list_add_tail(&desc->node, &chan->pending_list);
1901 	chan->desc_pendingcount++;
1902 
1903 	if (chan->has_sg && (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA)
1904 	    && unlikely(chan->desc_pendingcount > chan->num_frms)) {
1905 		dev_dbg(chan->dev, "desc pendingcount is too high\n");
1906 		chan->desc_pendingcount = chan->num_frms;
1907 	}
1908 }
1909 
1910 /**
1911  * xilinx_dma_tx_submit - Submit DMA transaction
1912  * @tx: Async transaction descriptor
1913  *
1914  * Return: cookie value on success and failure value on error
1915  */
1916 static dma_cookie_t xilinx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
1917 {
1918 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
1919 	struct xilinx_dma_chan *chan = to_xilinx_chan(tx->chan);
1920 	dma_cookie_t cookie;
1921 	unsigned long flags;
1922 	int err;
1923 
1924 	if (chan->cyclic) {
1925 		xilinx_dma_free_tx_descriptor(chan, desc);
1926 		return -EBUSY;
1927 	}
1928 
1929 	if (chan->err) {
1930 		/*
1931 		 * If reset fails, need to hard reset the system.
1932 		 * Channel is no longer functional
1933 		 */
1934 		err = xilinx_dma_chan_reset(chan);
1935 		if (err < 0)
1936 			return err;
1937 	}
1938 
1939 	spin_lock_irqsave(&chan->lock, flags);
1940 
1941 	cookie = dma_cookie_assign(tx);
1942 
1943 	/* Put this transaction onto the tail of the pending queue */
1944 	append_desc_queue(chan, desc);
1945 
1946 	if (desc->cyclic)
1947 		chan->cyclic = true;
1948 
1949 	spin_unlock_irqrestore(&chan->lock, flags);
1950 
1951 	return cookie;
1952 }
1953 
1954 /**
1955  * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
1956  *	DMA_SLAVE transaction
1957  * @dchan: DMA channel
1958  * @xt: Interleaved template pointer
1959  * @flags: transfer ack flags
1960  *
1961  * Return: Async transaction descriptor on success and NULL on failure
1962  */
1963 static struct dma_async_tx_descriptor *
1964 xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
1965 				 struct dma_interleaved_template *xt,
1966 				 unsigned long flags)
1967 {
1968 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1969 	struct xilinx_dma_tx_descriptor *desc;
1970 	struct xilinx_vdma_tx_segment *segment;
1971 	struct xilinx_vdma_desc_hw *hw;
1972 
1973 	if (!is_slave_direction(xt->dir))
1974 		return NULL;
1975 
1976 	if (!xt->numf || !xt->sgl[0].size)
1977 		return NULL;
1978 
1979 	if (xt->frame_size != 1)
1980 		return NULL;
1981 
1982 	/* Allocate a transaction descriptor. */
1983 	desc = xilinx_dma_alloc_tx_descriptor(chan);
1984 	if (!desc)
1985 		return NULL;
1986 
1987 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
1988 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
1989 	async_tx_ack(&desc->async_tx);
1990 
1991 	/* Allocate the link descriptor from DMA pool */
1992 	segment = xilinx_vdma_alloc_tx_segment(chan);
1993 	if (!segment)
1994 		goto error;
1995 
1996 	/* Fill in the hardware descriptor */
1997 	hw = &segment->hw;
1998 	hw->vsize = xt->numf;
1999 	hw->hsize = xt->sgl[0].size;
2000 	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
2001 			XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT;
2002 	hw->stride |= chan->config.frm_dly <<
2003 			XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
2004 
2005 	if (xt->dir != DMA_MEM_TO_DEV) {
2006 		if (chan->ext_addr) {
2007 			hw->buf_addr = lower_32_bits(xt->dst_start);
2008 			hw->buf_addr_msb = upper_32_bits(xt->dst_start);
2009 		} else {
2010 			hw->buf_addr = xt->dst_start;
2011 		}
2012 	} else {
2013 		if (chan->ext_addr) {
2014 			hw->buf_addr = lower_32_bits(xt->src_start);
2015 			hw->buf_addr_msb = upper_32_bits(xt->src_start);
2016 		} else {
2017 			hw->buf_addr = xt->src_start;
2018 		}
2019 	}
2020 
2021 	/* Insert the segment into the descriptor segments list. */
2022 	list_add_tail(&segment->node, &desc->segments);
2023 
2024 	/* Link the last hardware descriptor with the first. */
2025 	segment = list_first_entry(&desc->segments,
2026 				   struct xilinx_vdma_tx_segment, node);
2027 	desc->async_tx.phys = segment->phys;
2028 
2029 	return &desc->async_tx;
2030 
2031 error:
2032 	xilinx_dma_free_tx_descriptor(chan, desc);
2033 	return NULL;
2034 }
2035 
2036 /**
2037  * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
2038  * @dchan: DMA channel
2039  * @dma_dst: destination address
2040  * @dma_src: source address
2041  * @len: transfer length
2042  * @flags: transfer ack flags
2043  *
2044  * Return: Async transaction descriptor on success and NULL on failure
2045  */
2046 static struct dma_async_tx_descriptor *
2047 xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
2048 			dma_addr_t dma_src, size_t len, unsigned long flags)
2049 {
2050 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2051 	struct xilinx_dma_tx_descriptor *desc;
2052 	struct xilinx_cdma_tx_segment *segment;
2053 	struct xilinx_cdma_desc_hw *hw;
2054 
2055 	if (!len || len > chan->xdev->max_buffer_len)
2056 		return NULL;
2057 
2058 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2059 	if (!desc)
2060 		return NULL;
2061 
2062 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2063 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2064 
2065 	/* Allocate the link descriptor from DMA pool */
2066 	segment = xilinx_cdma_alloc_tx_segment(chan);
2067 	if (!segment)
2068 		goto error;
2069 
2070 	hw = &segment->hw;
2071 	hw->control = len;
2072 	hw->src_addr = dma_src;
2073 	hw->dest_addr = dma_dst;
2074 	if (chan->ext_addr) {
2075 		hw->src_addr_msb = upper_32_bits(dma_src);
2076 		hw->dest_addr_msb = upper_32_bits(dma_dst);
2077 	}
2078 
2079 	/* Insert the segment into the descriptor segments list. */
2080 	list_add_tail(&segment->node, &desc->segments);
2081 
2082 	desc->async_tx.phys = segment->phys;
2083 	hw->next_desc = segment->phys;
2084 
2085 	return &desc->async_tx;
2086 
2087 error:
2088 	xilinx_dma_free_tx_descriptor(chan, desc);
2089 	return NULL;
2090 }
2091 
2092 /**
2093  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2094  * @dchan: DMA channel
2095  * @sgl: scatterlist to transfer to/from
2096  * @sg_len: number of entries in @scatterlist
2097  * @direction: DMA direction
2098  * @flags: transfer ack flags
2099  * @context: APP words of the descriptor
2100  *
2101  * Return: Async transaction descriptor on success and NULL on failure
2102  */
2103 static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
2104 	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
2105 	enum dma_transfer_direction direction, unsigned long flags,
2106 	void *context)
2107 {
2108 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2109 	struct xilinx_dma_tx_descriptor *desc;
2110 	struct xilinx_axidma_tx_segment *segment = NULL;
2111 	u32 *app_w = (u32 *)context;
2112 	struct scatterlist *sg;
2113 	size_t copy;
2114 	size_t sg_used;
2115 	unsigned int i;
2116 
2117 	if (!is_slave_direction(direction))
2118 		return NULL;
2119 
2120 	/* Allocate a transaction descriptor. */
2121 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2122 	if (!desc)
2123 		return NULL;
2124 
2125 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2126 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2127 
2128 	/* Build transactions using information in the scatter gather list */
2129 	for_each_sg(sgl, sg, sg_len, i) {
2130 		sg_used = 0;
2131 
2132 		/* Loop until the entire scatterlist entry is used */
2133 		while (sg_used < sg_dma_len(sg)) {
2134 			struct xilinx_axidma_desc_hw *hw;
2135 
2136 			/* Get a free segment */
2137 			segment = xilinx_axidma_alloc_tx_segment(chan);
2138 			if (!segment)
2139 				goto error;
2140 
2141 			/*
2142 			 * Calculate the maximum number of bytes to transfer,
2143 			 * making sure it is less than the hw limit
2144 			 */
2145 			copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
2146 							sg_used);
2147 			hw = &segment->hw;
2148 
2149 			/* Fill in the descriptor */
2150 			xilinx_axidma_buf(chan, hw, sg_dma_address(sg),
2151 					  sg_used, 0);
2152 
2153 			hw->control = copy;
2154 
2155 			if (chan->direction == DMA_MEM_TO_DEV) {
2156 				if (app_w)
2157 					memcpy(hw->app, app_w, sizeof(u32) *
2158 					       XILINX_DMA_NUM_APP_WORDS);
2159 			}
2160 
2161 			sg_used += copy;
2162 
2163 			/*
2164 			 * Insert the segment into the descriptor segments
2165 			 * list.
2166 			 */
2167 			list_add_tail(&segment->node, &desc->segments);
2168 		}
2169 	}
2170 
2171 	segment = list_first_entry(&desc->segments,
2172 				   struct xilinx_axidma_tx_segment, node);
2173 	desc->async_tx.phys = segment->phys;
2174 
2175 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2176 	if (chan->direction == DMA_MEM_TO_DEV) {
2177 		segment->hw.control |= XILINX_DMA_BD_SOP;
2178 		segment = list_last_entry(&desc->segments,
2179 					  struct xilinx_axidma_tx_segment,
2180 					  node);
2181 		segment->hw.control |= XILINX_DMA_BD_EOP;
2182 	}
2183 
2184 	return &desc->async_tx;
2185 
2186 error:
2187 	xilinx_dma_free_tx_descriptor(chan, desc);
2188 	return NULL;
2189 }
2190 
2191 /**
2192  * xilinx_dma_prep_dma_cyclic - prepare descriptors for a DMA_SLAVE transaction
2193  * @dchan: DMA channel
2194  * @buf_addr: Physical address of the buffer
2195  * @buf_len: Total length of the cyclic buffers
2196  * @period_len: length of individual cyclic buffer
2197  * @direction: DMA direction
2198  * @flags: transfer ack flags
2199  *
2200  * Return: Async transaction descriptor on success and NULL on failure
2201  */
2202 static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
2203 	struct dma_chan *dchan, dma_addr_t buf_addr, size_t buf_len,
2204 	size_t period_len, enum dma_transfer_direction direction,
2205 	unsigned long flags)
2206 {
2207 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2208 	struct xilinx_dma_tx_descriptor *desc;
2209 	struct xilinx_axidma_tx_segment *segment, *head_segment, *prev = NULL;
2210 	size_t copy, sg_used;
2211 	unsigned int num_periods;
2212 	int i;
2213 	u32 reg;
2214 
2215 	if (!period_len)
2216 		return NULL;
2217 
2218 	num_periods = buf_len / period_len;
2219 
2220 	if (!num_periods)
2221 		return NULL;
2222 
2223 	if (!is_slave_direction(direction))
2224 		return NULL;
2225 
2226 	/* Allocate a transaction descriptor. */
2227 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2228 	if (!desc)
2229 		return NULL;
2230 
2231 	chan->direction = direction;
2232 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2233 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2234 
2235 	for (i = 0; i < num_periods; ++i) {
2236 		sg_used = 0;
2237 
2238 		while (sg_used < period_len) {
2239 			struct xilinx_axidma_desc_hw *hw;
2240 
2241 			/* Get a free segment */
2242 			segment = xilinx_axidma_alloc_tx_segment(chan);
2243 			if (!segment)
2244 				goto error;
2245 
2246 			/*
2247 			 * Calculate the maximum number of bytes to transfer,
2248 			 * making sure it is less than the hw limit
2249 			 */
2250 			copy = xilinx_dma_calc_copysize(chan, period_len,
2251 							sg_used);
2252 			hw = &segment->hw;
2253 			xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
2254 					  period_len * i);
2255 			hw->control = copy;
2256 
2257 			if (prev)
2258 				prev->hw.next_desc = segment->phys;
2259 
2260 			prev = segment;
2261 			sg_used += copy;
2262 
2263 			/*
2264 			 * Insert the segment into the descriptor segments
2265 			 * list.
2266 			 */
2267 			list_add_tail(&segment->node, &desc->segments);
2268 		}
2269 	}
2270 
2271 	head_segment = list_first_entry(&desc->segments,
2272 				   struct xilinx_axidma_tx_segment, node);
2273 	desc->async_tx.phys = head_segment->phys;
2274 
2275 	desc->cyclic = true;
2276 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2277 	reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2278 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2279 
2280 	segment = list_last_entry(&desc->segments,
2281 				  struct xilinx_axidma_tx_segment,
2282 				  node);
2283 	segment->hw.next_desc = (u32) head_segment->phys;
2284 
2285 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2286 	if (direction == DMA_MEM_TO_DEV) {
2287 		head_segment->hw.control |= XILINX_DMA_BD_SOP;
2288 		segment->hw.control |= XILINX_DMA_BD_EOP;
2289 	}
2290 
2291 	return &desc->async_tx;
2292 
2293 error:
2294 	xilinx_dma_free_tx_descriptor(chan, desc);
2295 	return NULL;
2296 }
2297 
2298 /**
2299  * xilinx_mcdma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2300  * @dchan: DMA channel
2301  * @sgl: scatterlist to transfer to/from
2302  * @sg_len: number of entries in @scatterlist
2303  * @direction: DMA direction
2304  * @flags: transfer ack flags
2305  * @context: APP words of the descriptor
2306  *
2307  * Return: Async transaction descriptor on success and NULL on failure
2308  */
2309 static struct dma_async_tx_descriptor *
2310 xilinx_mcdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
2311 			   unsigned int sg_len,
2312 			   enum dma_transfer_direction direction,
2313 			   unsigned long flags, void *context)
2314 {
2315 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2316 	struct xilinx_dma_tx_descriptor *desc;
2317 	struct xilinx_aximcdma_tx_segment *segment = NULL;
2318 	u32 *app_w = (u32 *)context;
2319 	struct scatterlist *sg;
2320 	size_t copy;
2321 	size_t sg_used;
2322 	unsigned int i;
2323 
2324 	if (!is_slave_direction(direction))
2325 		return NULL;
2326 
2327 	/* Allocate a transaction descriptor. */
2328 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2329 	if (!desc)
2330 		return NULL;
2331 
2332 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2333 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2334 
2335 	/* Build transactions using information in the scatter gather list */
2336 	for_each_sg(sgl, sg, sg_len, i) {
2337 		sg_used = 0;
2338 
2339 		/* Loop until the entire scatterlist entry is used */
2340 		while (sg_used < sg_dma_len(sg)) {
2341 			struct xilinx_aximcdma_desc_hw *hw;
2342 
2343 			/* Get a free segment */
2344 			segment = xilinx_aximcdma_alloc_tx_segment(chan);
2345 			if (!segment)
2346 				goto error;
2347 
2348 			/*
2349 			 * Calculate the maximum number of bytes to transfer,
2350 			 * making sure it is less than the hw limit
2351 			 */
2352 			copy = min_t(size_t, sg_dma_len(sg) - sg_used,
2353 				     chan->xdev->max_buffer_len);
2354 			hw = &segment->hw;
2355 
2356 			/* Fill in the descriptor */
2357 			xilinx_aximcdma_buf(chan, hw, sg_dma_address(sg),
2358 					    sg_used);
2359 			hw->control = copy;
2360 
2361 			if (chan->direction == DMA_MEM_TO_DEV && app_w) {
2362 				memcpy(hw->app, app_w, sizeof(u32) *
2363 				       XILINX_DMA_NUM_APP_WORDS);
2364 			}
2365 
2366 			sg_used += copy;
2367 			/*
2368 			 * Insert the segment into the descriptor segments
2369 			 * list.
2370 			 */
2371 			list_add_tail(&segment->node, &desc->segments);
2372 		}
2373 	}
2374 
2375 	segment = list_first_entry(&desc->segments,
2376 				   struct xilinx_aximcdma_tx_segment, node);
2377 	desc->async_tx.phys = segment->phys;
2378 
2379 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2380 	if (chan->direction == DMA_MEM_TO_DEV) {
2381 		segment->hw.control |= XILINX_MCDMA_BD_SOP;
2382 		segment = list_last_entry(&desc->segments,
2383 					  struct xilinx_aximcdma_tx_segment,
2384 					  node);
2385 		segment->hw.control |= XILINX_MCDMA_BD_EOP;
2386 	}
2387 
2388 	return &desc->async_tx;
2389 
2390 error:
2391 	xilinx_dma_free_tx_descriptor(chan, desc);
2392 
2393 	return NULL;
2394 }
2395 
2396 /**
2397  * xilinx_dma_terminate_all - Halt the channel and free descriptors
2398  * @dchan: Driver specific DMA Channel pointer
2399  *
2400  * Return: '0' always.
2401  */
2402 static int xilinx_dma_terminate_all(struct dma_chan *dchan)
2403 {
2404 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2405 	u32 reg;
2406 	int err;
2407 
2408 	if (!chan->cyclic) {
2409 		err = chan->stop_transfer(chan);
2410 		if (err) {
2411 			dev_err(chan->dev, "Cannot stop channel %p: %x\n",
2412 				chan, dma_ctrl_read(chan,
2413 				XILINX_DMA_REG_DMASR));
2414 			chan->err = true;
2415 		}
2416 	}
2417 
2418 	xilinx_dma_chan_reset(chan);
2419 	/* Remove and free all of the descriptors in the lists */
2420 	xilinx_dma_free_descriptors(chan);
2421 	chan->idle = true;
2422 
2423 	if (chan->cyclic) {
2424 		reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2425 		reg &= ~XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2426 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2427 		chan->cyclic = false;
2428 	}
2429 
2430 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
2431 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2432 			     XILINX_CDMA_CR_SGMODE);
2433 
2434 	return 0;
2435 }
2436 
2437 /**
2438  * xilinx_dma_channel_set_config - Configure VDMA channel
2439  * Run-time configuration for Axi VDMA, supports:
2440  * . halt the channel
2441  * . configure interrupt coalescing and inter-packet delay threshold
2442  * . start/stop parking
2443  * . enable genlock
2444  *
2445  * @dchan: DMA channel
2446  * @cfg: VDMA device configuration pointer
2447  *
2448  * Return: '0' on success and failure value on error
2449  */
2450 int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
2451 					struct xilinx_vdma_config *cfg)
2452 {
2453 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2454 	u32 dmacr;
2455 
2456 	if (cfg->reset)
2457 		return xilinx_dma_chan_reset(chan);
2458 
2459 	dmacr = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2460 
2461 	chan->config.frm_dly = cfg->frm_dly;
2462 	chan->config.park = cfg->park;
2463 
2464 	/* genlock settings */
2465 	chan->config.gen_lock = cfg->gen_lock;
2466 	chan->config.master = cfg->master;
2467 
2468 	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
2469 	if (cfg->gen_lock && chan->genlock) {
2470 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
2471 		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
2472 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
2473 	}
2474 
2475 	chan->config.frm_cnt_en = cfg->frm_cnt_en;
2476 	chan->config.vflip_en = cfg->vflip_en;
2477 
2478 	if (cfg->park)
2479 		chan->config.park_frm = cfg->park_frm;
2480 	else
2481 		chan->config.park_frm = -1;
2482 
2483 	chan->config.coalesc = cfg->coalesc;
2484 	chan->config.delay = cfg->delay;
2485 
2486 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
2487 		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
2488 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
2489 		chan->config.coalesc = cfg->coalesc;
2490 	}
2491 
2492 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
2493 		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
2494 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
2495 		chan->config.delay = cfg->delay;
2496 	}
2497 
2498 	/* FSync Source selection */
2499 	dmacr &= ~XILINX_DMA_DMACR_FSYNCSRC_MASK;
2500 	dmacr |= cfg->ext_fsync << XILINX_DMA_DMACR_FSYNCSRC_SHIFT;
2501 
2502 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, dmacr);
2503 
2504 	return 0;
2505 }
2506 EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
2507 
2508 /* -----------------------------------------------------------------------------
2509  * Probe and remove
2510  */
2511 
2512 /**
2513  * xilinx_dma_chan_remove - Per Channel remove function
2514  * @chan: Driver specific DMA channel
2515  */
2516 static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
2517 {
2518 	/* Disable all interrupts */
2519 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2520 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
2521 
2522 	if (chan->irq > 0)
2523 		free_irq(chan->irq, chan);
2524 
2525 	tasklet_kill(&chan->tasklet);
2526 
2527 	list_del(&chan->common.device_node);
2528 }
2529 
2530 static int axidma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2531 			    struct clk **tx_clk, struct clk **rx_clk,
2532 			    struct clk **sg_clk, struct clk **tmp_clk)
2533 {
2534 	int err;
2535 
2536 	*tmp_clk = NULL;
2537 
2538 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2539 	if (IS_ERR(*axi_clk)) {
2540 		err = PTR_ERR(*axi_clk);
2541 		if (err != -EPROBE_DEFER)
2542 			dev_err(&pdev->dev, "failed to get axi_aclk (%d)\n",
2543 				err);
2544 		return err;
2545 	}
2546 
2547 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2548 	if (IS_ERR(*tx_clk))
2549 		*tx_clk = NULL;
2550 
2551 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2552 	if (IS_ERR(*rx_clk))
2553 		*rx_clk = NULL;
2554 
2555 	*sg_clk = devm_clk_get(&pdev->dev, "m_axi_sg_aclk");
2556 	if (IS_ERR(*sg_clk))
2557 		*sg_clk = NULL;
2558 
2559 	err = clk_prepare_enable(*axi_clk);
2560 	if (err) {
2561 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2562 		return err;
2563 	}
2564 
2565 	err = clk_prepare_enable(*tx_clk);
2566 	if (err) {
2567 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2568 		goto err_disable_axiclk;
2569 	}
2570 
2571 	err = clk_prepare_enable(*rx_clk);
2572 	if (err) {
2573 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2574 		goto err_disable_txclk;
2575 	}
2576 
2577 	err = clk_prepare_enable(*sg_clk);
2578 	if (err) {
2579 		dev_err(&pdev->dev, "failed to enable sg_clk (%d)\n", err);
2580 		goto err_disable_rxclk;
2581 	}
2582 
2583 	return 0;
2584 
2585 err_disable_rxclk:
2586 	clk_disable_unprepare(*rx_clk);
2587 err_disable_txclk:
2588 	clk_disable_unprepare(*tx_clk);
2589 err_disable_axiclk:
2590 	clk_disable_unprepare(*axi_clk);
2591 
2592 	return err;
2593 }
2594 
2595 static int axicdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2596 			    struct clk **dev_clk, struct clk **tmp_clk,
2597 			    struct clk **tmp1_clk, struct clk **tmp2_clk)
2598 {
2599 	int err;
2600 
2601 	*tmp_clk = NULL;
2602 	*tmp1_clk = NULL;
2603 	*tmp2_clk = NULL;
2604 
2605 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2606 	if (IS_ERR(*axi_clk)) {
2607 		err = PTR_ERR(*axi_clk);
2608 		if (err != -EPROBE_DEFER)
2609 			dev_err(&pdev->dev, "failed to get axi_clk (%d)\n",
2610 				err);
2611 		return err;
2612 	}
2613 
2614 	*dev_clk = devm_clk_get(&pdev->dev, "m_axi_aclk");
2615 	if (IS_ERR(*dev_clk)) {
2616 		err = PTR_ERR(*dev_clk);
2617 		if (err != -EPROBE_DEFER)
2618 			dev_err(&pdev->dev, "failed to get dev_clk (%d)\n",
2619 				err);
2620 		return err;
2621 	}
2622 
2623 	err = clk_prepare_enable(*axi_clk);
2624 	if (err) {
2625 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2626 		return err;
2627 	}
2628 
2629 	err = clk_prepare_enable(*dev_clk);
2630 	if (err) {
2631 		dev_err(&pdev->dev, "failed to enable dev_clk (%d)\n", err);
2632 		goto err_disable_axiclk;
2633 	}
2634 
2635 	return 0;
2636 
2637 err_disable_axiclk:
2638 	clk_disable_unprepare(*axi_clk);
2639 
2640 	return err;
2641 }
2642 
2643 static int axivdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2644 			    struct clk **tx_clk, struct clk **txs_clk,
2645 			    struct clk **rx_clk, struct clk **rxs_clk)
2646 {
2647 	int err;
2648 
2649 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2650 	if (IS_ERR(*axi_clk)) {
2651 		err = PTR_ERR(*axi_clk);
2652 		if (err != -EPROBE_DEFER)
2653 			dev_err(&pdev->dev, "failed to get axi_aclk (%d)\n",
2654 				err);
2655 		return err;
2656 	}
2657 
2658 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2659 	if (IS_ERR(*tx_clk))
2660 		*tx_clk = NULL;
2661 
2662 	*txs_clk = devm_clk_get(&pdev->dev, "m_axis_mm2s_aclk");
2663 	if (IS_ERR(*txs_clk))
2664 		*txs_clk = NULL;
2665 
2666 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2667 	if (IS_ERR(*rx_clk))
2668 		*rx_clk = NULL;
2669 
2670 	*rxs_clk = devm_clk_get(&pdev->dev, "s_axis_s2mm_aclk");
2671 	if (IS_ERR(*rxs_clk))
2672 		*rxs_clk = NULL;
2673 
2674 	err = clk_prepare_enable(*axi_clk);
2675 	if (err) {
2676 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n",
2677 			err);
2678 		return err;
2679 	}
2680 
2681 	err = clk_prepare_enable(*tx_clk);
2682 	if (err) {
2683 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2684 		goto err_disable_axiclk;
2685 	}
2686 
2687 	err = clk_prepare_enable(*txs_clk);
2688 	if (err) {
2689 		dev_err(&pdev->dev, "failed to enable txs_clk (%d)\n", err);
2690 		goto err_disable_txclk;
2691 	}
2692 
2693 	err = clk_prepare_enable(*rx_clk);
2694 	if (err) {
2695 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2696 		goto err_disable_txsclk;
2697 	}
2698 
2699 	err = clk_prepare_enable(*rxs_clk);
2700 	if (err) {
2701 		dev_err(&pdev->dev, "failed to enable rxs_clk (%d)\n", err);
2702 		goto err_disable_rxclk;
2703 	}
2704 
2705 	return 0;
2706 
2707 err_disable_rxclk:
2708 	clk_disable_unprepare(*rx_clk);
2709 err_disable_txsclk:
2710 	clk_disable_unprepare(*txs_clk);
2711 err_disable_txclk:
2712 	clk_disable_unprepare(*tx_clk);
2713 err_disable_axiclk:
2714 	clk_disable_unprepare(*axi_clk);
2715 
2716 	return err;
2717 }
2718 
2719 static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
2720 {
2721 	clk_disable_unprepare(xdev->rxs_clk);
2722 	clk_disable_unprepare(xdev->rx_clk);
2723 	clk_disable_unprepare(xdev->txs_clk);
2724 	clk_disable_unprepare(xdev->tx_clk);
2725 	clk_disable_unprepare(xdev->axi_clk);
2726 }
2727 
2728 /**
2729  * xilinx_dma_chan_probe - Per Channel Probing
2730  * It get channel features from the device tree entry and
2731  * initialize special channel handling routines
2732  *
2733  * @xdev: Driver specific device structure
2734  * @node: Device node
2735  *
2736  * Return: '0' on success and failure value on error
2737  */
2738 static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
2739 				  struct device_node *node)
2740 {
2741 	struct xilinx_dma_chan *chan;
2742 	bool has_dre = false;
2743 	u32 value, width;
2744 	int err;
2745 
2746 	/* Allocate and initialize the channel structure */
2747 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
2748 	if (!chan)
2749 		return -ENOMEM;
2750 
2751 	chan->dev = xdev->dev;
2752 	chan->xdev = xdev;
2753 	chan->desc_pendingcount = 0x0;
2754 	chan->ext_addr = xdev->ext_addr;
2755 	/* This variable ensures that descriptors are not
2756 	 * Submitted when dma engine is in progress. This variable is
2757 	 * Added to avoid polling for a bit in the status register to
2758 	 * Know dma state in the driver hot path.
2759 	 */
2760 	chan->idle = true;
2761 
2762 	spin_lock_init(&chan->lock);
2763 	INIT_LIST_HEAD(&chan->pending_list);
2764 	INIT_LIST_HEAD(&chan->done_list);
2765 	INIT_LIST_HEAD(&chan->active_list);
2766 	INIT_LIST_HEAD(&chan->free_seg_list);
2767 
2768 	/* Retrieve the channel properties from the device tree */
2769 	has_dre = of_property_read_bool(node, "xlnx,include-dre");
2770 
2771 	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
2772 
2773 	err = of_property_read_u32(node, "xlnx,datawidth", &value);
2774 	if (err) {
2775 		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
2776 		return err;
2777 	}
2778 	width = value >> 3; /* Convert bits to bytes */
2779 
2780 	/* If data width is greater than 8 bytes, DRE is not in hw */
2781 	if (width > 8)
2782 		has_dre = false;
2783 
2784 	if (!has_dre)
2785 		xdev->common.copy_align = fls(width - 1);
2786 
2787 	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel") ||
2788 	    of_device_is_compatible(node, "xlnx,axi-dma-mm2s-channel") ||
2789 	    of_device_is_compatible(node, "xlnx,axi-cdma-channel")) {
2790 		chan->direction = DMA_MEM_TO_DEV;
2791 		chan->id = xdev->mm2s_chan_id++;
2792 		chan->tdest = chan->id;
2793 
2794 		chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
2795 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2796 			chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
2797 			chan->config.park = 1;
2798 
2799 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2800 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
2801 				chan->flush_on_fsync = true;
2802 		}
2803 	} else if (of_device_is_compatible(node,
2804 					   "xlnx,axi-vdma-s2mm-channel") ||
2805 		   of_device_is_compatible(node,
2806 					   "xlnx,axi-dma-s2mm-channel")) {
2807 		chan->direction = DMA_DEV_TO_MEM;
2808 		chan->id = xdev->s2mm_chan_id++;
2809 		chan->tdest = chan->id - xdev->dma_config->max_channels / 2;
2810 		chan->has_vflip = of_property_read_bool(node,
2811 					"xlnx,enable-vert-flip");
2812 		if (chan->has_vflip) {
2813 			chan->config.vflip_en = dma_read(chan,
2814 				XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP) &
2815 				XILINX_VDMA_ENABLE_VERTICAL_FLIP;
2816 		}
2817 
2818 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
2819 			chan->ctrl_offset = XILINX_MCDMA_S2MM_CTRL_OFFSET;
2820 		else
2821 			chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
2822 
2823 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2824 			chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
2825 			chan->config.park = 1;
2826 
2827 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2828 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
2829 				chan->flush_on_fsync = true;
2830 		}
2831 	} else {
2832 		dev_err(xdev->dev, "Invalid channel compatible node\n");
2833 		return -EINVAL;
2834 	}
2835 
2836 	/* Request the interrupt */
2837 	chan->irq = irq_of_parse_and_map(node, chan->tdest);
2838 	err = request_irq(chan->irq, xdev->dma_config->irq_handler,
2839 			  IRQF_SHARED, "xilinx-dma-controller", chan);
2840 	if (err) {
2841 		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
2842 		return err;
2843 	}
2844 
2845 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
2846 		chan->start_transfer = xilinx_dma_start_transfer;
2847 		chan->stop_transfer = xilinx_dma_stop_transfer;
2848 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
2849 		chan->start_transfer = xilinx_mcdma_start_transfer;
2850 		chan->stop_transfer = xilinx_dma_stop_transfer;
2851 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
2852 		chan->start_transfer = xilinx_cdma_start_transfer;
2853 		chan->stop_transfer = xilinx_cdma_stop_transfer;
2854 	} else {
2855 		chan->start_transfer = xilinx_vdma_start_transfer;
2856 		chan->stop_transfer = xilinx_dma_stop_transfer;
2857 	}
2858 
2859 	/* check if SG is enabled (only for AXIDMA and CDMA) */
2860 	if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) {
2861 		if (dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) &
2862 		    XILINX_DMA_DMASR_SG_MASK)
2863 			chan->has_sg = true;
2864 		dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id,
2865 			chan->has_sg ? "enabled" : "disabled");
2866 	}
2867 
2868 	/* Initialize the tasklet */
2869 	tasklet_init(&chan->tasklet, xilinx_dma_do_tasklet,
2870 			(unsigned long)chan);
2871 
2872 	/*
2873 	 * Initialize the DMA channel and add it to the DMA engine channels
2874 	 * list.
2875 	 */
2876 	chan->common.device = &xdev->common;
2877 
2878 	list_add_tail(&chan->common.device_node, &xdev->common.channels);
2879 	xdev->chan[chan->id] = chan;
2880 
2881 	/* Reset the channel */
2882 	err = xilinx_dma_chan_reset(chan);
2883 	if (err < 0) {
2884 		dev_err(xdev->dev, "Reset channel failed\n");
2885 		return err;
2886 	}
2887 
2888 	return 0;
2889 }
2890 
2891 /**
2892  * xilinx_dma_child_probe - Per child node probe
2893  * It get number of dma-channels per child node from
2894  * device-tree and initializes all the channels.
2895  *
2896  * @xdev: Driver specific device structure
2897  * @node: Device node
2898  *
2899  * Return: 0 always.
2900  */
2901 static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
2902 				    struct device_node *node)
2903 {
2904 	int ret, i, nr_channels = 1;
2905 
2906 	ret = of_property_read_u32(node, "dma-channels", &nr_channels);
2907 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA && ret < 0)
2908 		dev_warn(xdev->dev, "missing dma-channels property\n");
2909 
2910 	for (i = 0; i < nr_channels; i++)
2911 		xilinx_dma_chan_probe(xdev, node);
2912 
2913 	return 0;
2914 }
2915 
2916 /**
2917  * of_dma_xilinx_xlate - Translation function
2918  * @dma_spec: Pointer to DMA specifier as found in the device tree
2919  * @ofdma: Pointer to DMA controller data
2920  *
2921  * Return: DMA channel pointer on success and NULL on error
2922  */
2923 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
2924 						struct of_dma *ofdma)
2925 {
2926 	struct xilinx_dma_device *xdev = ofdma->of_dma_data;
2927 	int chan_id = dma_spec->args[0];
2928 
2929 	if (chan_id >= xdev->dma_config->max_channels || !xdev->chan[chan_id])
2930 		return NULL;
2931 
2932 	return dma_get_slave_channel(&xdev->chan[chan_id]->common);
2933 }
2934 
2935 static const struct xilinx_dma_config axidma_config = {
2936 	.dmatype = XDMA_TYPE_AXIDMA,
2937 	.clk_init = axidma_clk_init,
2938 	.irq_handler = xilinx_dma_irq_handler,
2939 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
2940 };
2941 
2942 static const struct xilinx_dma_config aximcdma_config = {
2943 	.dmatype = XDMA_TYPE_AXIMCDMA,
2944 	.clk_init = axidma_clk_init,
2945 	.irq_handler = xilinx_mcdma_irq_handler,
2946 	.max_channels = XILINX_MCDMA_MAX_CHANS_PER_DEVICE,
2947 };
2948 static const struct xilinx_dma_config axicdma_config = {
2949 	.dmatype = XDMA_TYPE_CDMA,
2950 	.clk_init = axicdma_clk_init,
2951 	.irq_handler = xilinx_dma_irq_handler,
2952 	.max_channels = XILINX_CDMA_MAX_CHANS_PER_DEVICE,
2953 };
2954 
2955 static const struct xilinx_dma_config axivdma_config = {
2956 	.dmatype = XDMA_TYPE_VDMA,
2957 	.clk_init = axivdma_clk_init,
2958 	.irq_handler = xilinx_dma_irq_handler,
2959 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
2960 };
2961 
2962 static const struct of_device_id xilinx_dma_of_ids[] = {
2963 	{ .compatible = "xlnx,axi-dma-1.00.a", .data = &axidma_config },
2964 	{ .compatible = "xlnx,axi-cdma-1.00.a", .data = &axicdma_config },
2965 	{ .compatible = "xlnx,axi-vdma-1.00.a", .data = &axivdma_config },
2966 	{ .compatible = "xlnx,axi-mcdma-1.00.a", .data = &aximcdma_config },
2967 	{}
2968 };
2969 MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
2970 
2971 /**
2972  * xilinx_dma_probe - Driver probe function
2973  * @pdev: Pointer to the platform_device structure
2974  *
2975  * Return: '0' on success and failure value on error
2976  */
2977 static int xilinx_dma_probe(struct platform_device *pdev)
2978 {
2979 	int (*clk_init)(struct platform_device *, struct clk **, struct clk **,
2980 			struct clk **, struct clk **, struct clk **)
2981 					= axivdma_clk_init;
2982 	struct device_node *node = pdev->dev.of_node;
2983 	struct xilinx_dma_device *xdev;
2984 	struct device_node *child, *np = pdev->dev.of_node;
2985 	u32 num_frames, addr_width, len_width;
2986 	int i, err;
2987 
2988 	/* Allocate and initialize the DMA engine structure */
2989 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
2990 	if (!xdev)
2991 		return -ENOMEM;
2992 
2993 	xdev->dev = &pdev->dev;
2994 	if (np) {
2995 		const struct of_device_id *match;
2996 
2997 		match = of_match_node(xilinx_dma_of_ids, np);
2998 		if (match && match->data) {
2999 			xdev->dma_config = match->data;
3000 			clk_init = xdev->dma_config->clk_init;
3001 		}
3002 	}
3003 
3004 	err = clk_init(pdev, &xdev->axi_clk, &xdev->tx_clk, &xdev->txs_clk,
3005 		       &xdev->rx_clk, &xdev->rxs_clk);
3006 	if (err)
3007 		return err;
3008 
3009 	/* Request and map I/O memory */
3010 	xdev->regs = devm_platform_ioremap_resource(pdev, 0);
3011 	if (IS_ERR(xdev->regs))
3012 		return PTR_ERR(xdev->regs);
3013 
3014 	/* Retrieve the DMA engine properties from the device tree */
3015 	xdev->max_buffer_len = GENMASK(XILINX_DMA_MAX_TRANS_LEN_MAX - 1, 0);
3016 	xdev->s2mm_chan_id = xdev->dma_config->max_channels / 2;
3017 
3018 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA ||
3019 	    xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3020 		if (!of_property_read_u32(node, "xlnx,sg-length-width",
3021 					  &len_width)) {
3022 			if (len_width < XILINX_DMA_MAX_TRANS_LEN_MIN ||
3023 			    len_width > XILINX_DMA_V2_MAX_TRANS_LEN_MAX) {
3024 				dev_warn(xdev->dev,
3025 					 "invalid xlnx,sg-length-width property value. Using default width\n");
3026 			} else {
3027 				if (len_width > XILINX_DMA_MAX_TRANS_LEN_MAX)
3028 					dev_warn(xdev->dev, "Please ensure that IP supports buffer length > 23 bits\n");
3029 				xdev->max_buffer_len =
3030 					GENMASK(len_width - 1, 0);
3031 			}
3032 		}
3033 	}
3034 
3035 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3036 		err = of_property_read_u32(node, "xlnx,num-fstores",
3037 					   &num_frames);
3038 		if (err < 0) {
3039 			dev_err(xdev->dev,
3040 				"missing xlnx,num-fstores property\n");
3041 			return err;
3042 		}
3043 
3044 		err = of_property_read_u32(node, "xlnx,flush-fsync",
3045 					   &xdev->flush_on_fsync);
3046 		if (err < 0)
3047 			dev_warn(xdev->dev,
3048 				 "missing xlnx,flush-fsync property\n");
3049 	}
3050 
3051 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
3052 	if (err < 0)
3053 		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
3054 
3055 	if (addr_width > 32)
3056 		xdev->ext_addr = true;
3057 	else
3058 		xdev->ext_addr = false;
3059 
3060 	/* Set the dma mask bits */
3061 	dma_set_mask(xdev->dev, DMA_BIT_MASK(addr_width));
3062 
3063 	/* Initialize the DMA engine */
3064 	xdev->common.dev = &pdev->dev;
3065 
3066 	INIT_LIST_HEAD(&xdev->common.channels);
3067 	if (!(xdev->dma_config->dmatype == XDMA_TYPE_CDMA)) {
3068 		dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
3069 		dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
3070 	}
3071 
3072 	xdev->common.device_alloc_chan_resources =
3073 				xilinx_dma_alloc_chan_resources;
3074 	xdev->common.device_free_chan_resources =
3075 				xilinx_dma_free_chan_resources;
3076 	xdev->common.device_terminate_all = xilinx_dma_terminate_all;
3077 	xdev->common.device_tx_status = xilinx_dma_tx_status;
3078 	xdev->common.device_issue_pending = xilinx_dma_issue_pending;
3079 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3080 		dma_cap_set(DMA_CYCLIC, xdev->common.cap_mask);
3081 		xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
3082 		xdev->common.device_prep_dma_cyclic =
3083 					  xilinx_dma_prep_dma_cyclic;
3084 		/* Residue calculation is supported by only AXI DMA and CDMA */
3085 		xdev->common.residue_granularity =
3086 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3087 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
3088 		dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
3089 		xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
3090 		/* Residue calculation is supported by only AXI DMA and CDMA */
3091 		xdev->common.residue_granularity =
3092 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3093 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3094 		xdev->common.device_prep_slave_sg = xilinx_mcdma_prep_slave_sg;
3095 	} else {
3096 		xdev->common.device_prep_interleaved_dma =
3097 				xilinx_vdma_dma_prep_interleaved;
3098 	}
3099 
3100 	platform_set_drvdata(pdev, xdev);
3101 
3102 	/* Initialize the channels */
3103 	for_each_child_of_node(node, child) {
3104 		err = xilinx_dma_child_probe(xdev, child);
3105 		if (err < 0)
3106 			goto disable_clks;
3107 	}
3108 
3109 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3110 		for (i = 0; i < xdev->dma_config->max_channels; i++)
3111 			if (xdev->chan[i])
3112 				xdev->chan[i]->num_frms = num_frames;
3113 	}
3114 
3115 	/* Register the DMA engine with the core */
3116 	dma_async_device_register(&xdev->common);
3117 
3118 	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
3119 					 xdev);
3120 	if (err < 0) {
3121 		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
3122 		dma_async_device_unregister(&xdev->common);
3123 		goto error;
3124 	}
3125 
3126 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
3127 		dev_info(&pdev->dev, "Xilinx AXI DMA Engine Driver Probed!!\n");
3128 	else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA)
3129 		dev_info(&pdev->dev, "Xilinx AXI CDMA Engine Driver Probed!!\n");
3130 	else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
3131 		dev_info(&pdev->dev, "Xilinx AXI MCDMA Engine Driver Probed!!\n");
3132 	else
3133 		dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
3134 
3135 	return 0;
3136 
3137 disable_clks:
3138 	xdma_disable_allclks(xdev);
3139 error:
3140 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3141 		if (xdev->chan[i])
3142 			xilinx_dma_chan_remove(xdev->chan[i]);
3143 
3144 	return err;
3145 }
3146 
3147 /**
3148  * xilinx_dma_remove - Driver remove function
3149  * @pdev: Pointer to the platform_device structure
3150  *
3151  * Return: Always '0'
3152  */
3153 static int xilinx_dma_remove(struct platform_device *pdev)
3154 {
3155 	struct xilinx_dma_device *xdev = platform_get_drvdata(pdev);
3156 	int i;
3157 
3158 	of_dma_controller_free(pdev->dev.of_node);
3159 
3160 	dma_async_device_unregister(&xdev->common);
3161 
3162 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3163 		if (xdev->chan[i])
3164 			xilinx_dma_chan_remove(xdev->chan[i]);
3165 
3166 	xdma_disable_allclks(xdev);
3167 
3168 	return 0;
3169 }
3170 
3171 static struct platform_driver xilinx_vdma_driver = {
3172 	.driver = {
3173 		.name = "xilinx-vdma",
3174 		.of_match_table = xilinx_dma_of_ids,
3175 	},
3176 	.probe = xilinx_dma_probe,
3177 	.remove = xilinx_dma_remove,
3178 };
3179 
3180 module_platform_driver(xilinx_vdma_driver);
3181 
3182 MODULE_AUTHOR("Xilinx, Inc.");
3183 MODULE_DESCRIPTION("Xilinx VDMA driver");
3184 MODULE_LICENSE("GPL v2");
3185