xref: /openbmc/linux/drivers/dma/xilinx/xilinx_dma.c (revision d9fd5a71)
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_atomic(chan->xdev->regs + chan->ctrl_offset + reg, \
521 				  val, 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_aximcdma_tx_segment *aximcdma_seg;
952 	struct xilinx_cdma_desc_hw *cdma_hw;
953 	struct xilinx_axidma_desc_hw *axidma_hw;
954 	struct xilinx_aximcdma_desc_hw *aximcdma_hw;
955 	struct list_head *entry;
956 	u32 residue = 0;
957 
958 	list_for_each(entry, &desc->segments) {
959 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
960 			cdma_seg = list_entry(entry,
961 					      struct xilinx_cdma_tx_segment,
962 					      node);
963 			cdma_hw = &cdma_seg->hw;
964 			residue += (cdma_hw->control - cdma_hw->status) &
965 				   chan->xdev->max_buffer_len;
966 		} else if (chan->xdev->dma_config->dmatype ==
967 			   XDMA_TYPE_AXIDMA) {
968 			axidma_seg = list_entry(entry,
969 						struct xilinx_axidma_tx_segment,
970 						node);
971 			axidma_hw = &axidma_seg->hw;
972 			residue += (axidma_hw->control - axidma_hw->status) &
973 				   chan->xdev->max_buffer_len;
974 		} else {
975 			aximcdma_seg =
976 				list_entry(entry,
977 					   struct xilinx_aximcdma_tx_segment,
978 					   node);
979 			aximcdma_hw = &aximcdma_seg->hw;
980 			residue +=
981 				(aximcdma_hw->control - aximcdma_hw->status) &
982 				chan->xdev->max_buffer_len;
983 		}
984 	}
985 
986 	return residue;
987 }
988 
989 /**
990  * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
991  * @chan: Driver specific dma channel
992  * @desc: dma transaction descriptor
993  * @flags: flags for spin lock
994  */
995 static void xilinx_dma_chan_handle_cyclic(struct xilinx_dma_chan *chan,
996 					  struct xilinx_dma_tx_descriptor *desc,
997 					  unsigned long *flags)
998 {
999 	dma_async_tx_callback callback;
1000 	void *callback_param;
1001 
1002 	callback = desc->async_tx.callback;
1003 	callback_param = desc->async_tx.callback_param;
1004 	if (callback) {
1005 		spin_unlock_irqrestore(&chan->lock, *flags);
1006 		callback(callback_param);
1007 		spin_lock_irqsave(&chan->lock, *flags);
1008 	}
1009 }
1010 
1011 /**
1012  * xilinx_dma_chan_desc_cleanup - Clean channel descriptors
1013  * @chan: Driver specific DMA channel
1014  */
1015 static void xilinx_dma_chan_desc_cleanup(struct xilinx_dma_chan *chan)
1016 {
1017 	struct xilinx_dma_tx_descriptor *desc, *next;
1018 	unsigned long flags;
1019 
1020 	spin_lock_irqsave(&chan->lock, flags);
1021 
1022 	list_for_each_entry_safe(desc, next, &chan->done_list, node) {
1023 		struct dmaengine_result result;
1024 
1025 		if (desc->cyclic) {
1026 			xilinx_dma_chan_handle_cyclic(chan, desc, &flags);
1027 			break;
1028 		}
1029 
1030 		/* Remove from the list of running transactions */
1031 		list_del(&desc->node);
1032 
1033 		if (unlikely(desc->err)) {
1034 			if (chan->direction == DMA_DEV_TO_MEM)
1035 				result.result = DMA_TRANS_READ_FAILED;
1036 			else
1037 				result.result = DMA_TRANS_WRITE_FAILED;
1038 		} else {
1039 			result.result = DMA_TRANS_NOERROR;
1040 		}
1041 
1042 		result.residue = desc->residue;
1043 
1044 		/* Run the link descriptor callback function */
1045 		spin_unlock_irqrestore(&chan->lock, flags);
1046 		dmaengine_desc_get_callback_invoke(&desc->async_tx, &result);
1047 		spin_lock_irqsave(&chan->lock, flags);
1048 
1049 		/* Run any dependencies, then free the descriptor */
1050 		dma_run_dependencies(&desc->async_tx);
1051 		xilinx_dma_free_tx_descriptor(chan, desc);
1052 	}
1053 
1054 	spin_unlock_irqrestore(&chan->lock, flags);
1055 }
1056 
1057 /**
1058  * xilinx_dma_do_tasklet - Schedule completion tasklet
1059  * @t: Pointer to the Xilinx DMA channel structure
1060  */
1061 static void xilinx_dma_do_tasklet(struct tasklet_struct *t)
1062 {
1063 	struct xilinx_dma_chan *chan = from_tasklet(chan, t, tasklet);
1064 
1065 	xilinx_dma_chan_desc_cleanup(chan);
1066 }
1067 
1068 /**
1069  * xilinx_dma_alloc_chan_resources - Allocate channel resources
1070  * @dchan: DMA channel
1071  *
1072  * Return: '0' on success and failure value on error
1073  */
1074 static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
1075 {
1076 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1077 	int i;
1078 
1079 	/* Has this channel already been allocated? */
1080 	if (chan->desc_pool)
1081 		return 0;
1082 
1083 	/*
1084 	 * We need the descriptor to be aligned to 64bytes
1085 	 * for meeting Xilinx VDMA specification requirement.
1086 	 */
1087 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1088 		/* Allocate the buffer descriptors. */
1089 		chan->seg_v = dma_alloc_coherent(chan->dev,
1090 						 sizeof(*chan->seg_v) * XILINX_DMA_NUM_DESCS,
1091 						 &chan->seg_p, GFP_KERNEL);
1092 		if (!chan->seg_v) {
1093 			dev_err(chan->dev,
1094 				"unable to allocate channel %d descriptors\n",
1095 				chan->id);
1096 			return -ENOMEM;
1097 		}
1098 		/*
1099 		 * For cyclic DMA mode we need to program the tail Descriptor
1100 		 * register with a value which is not a part of the BD chain
1101 		 * so allocating a desc segment during channel allocation for
1102 		 * programming tail descriptor.
1103 		 */
1104 		chan->cyclic_seg_v = dma_alloc_coherent(chan->dev,
1105 							sizeof(*chan->cyclic_seg_v),
1106 							&chan->cyclic_seg_p,
1107 							GFP_KERNEL);
1108 		if (!chan->cyclic_seg_v) {
1109 			dev_err(chan->dev,
1110 				"unable to allocate desc segment for cyclic DMA\n");
1111 			dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
1112 				XILINX_DMA_NUM_DESCS, chan->seg_v,
1113 				chan->seg_p);
1114 			return -ENOMEM;
1115 		}
1116 		chan->cyclic_seg_v->phys = chan->cyclic_seg_p;
1117 
1118 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1119 			chan->seg_v[i].hw.next_desc =
1120 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1121 				((i + 1) % XILINX_DMA_NUM_DESCS));
1122 			chan->seg_v[i].hw.next_desc_msb =
1123 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1124 				((i + 1) % XILINX_DMA_NUM_DESCS));
1125 			chan->seg_v[i].phys = chan->seg_p +
1126 				sizeof(*chan->seg_v) * i;
1127 			list_add_tail(&chan->seg_v[i].node,
1128 				      &chan->free_seg_list);
1129 		}
1130 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
1131 		/* Allocate the buffer descriptors. */
1132 		chan->seg_mv = dma_alloc_coherent(chan->dev,
1133 						  sizeof(*chan->seg_mv) *
1134 						  XILINX_DMA_NUM_DESCS,
1135 						  &chan->seg_p, GFP_KERNEL);
1136 		if (!chan->seg_mv) {
1137 			dev_err(chan->dev,
1138 				"unable to allocate channel %d descriptors\n",
1139 				chan->id);
1140 			return -ENOMEM;
1141 		}
1142 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1143 			chan->seg_mv[i].hw.next_desc =
1144 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1145 				((i + 1) % XILINX_DMA_NUM_DESCS));
1146 			chan->seg_mv[i].hw.next_desc_msb =
1147 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1148 				((i + 1) % XILINX_DMA_NUM_DESCS));
1149 			chan->seg_mv[i].phys = chan->seg_p +
1150 				sizeof(*chan->seg_mv) * i;
1151 			list_add_tail(&chan->seg_mv[i].node,
1152 				      &chan->free_seg_list);
1153 		}
1154 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1155 		chan->desc_pool = dma_pool_create("xilinx_cdma_desc_pool",
1156 				   chan->dev,
1157 				   sizeof(struct xilinx_cdma_tx_segment),
1158 				   __alignof__(struct xilinx_cdma_tx_segment),
1159 				   0);
1160 	} else {
1161 		chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
1162 				     chan->dev,
1163 				     sizeof(struct xilinx_vdma_tx_segment),
1164 				     __alignof__(struct xilinx_vdma_tx_segment),
1165 				     0);
1166 	}
1167 
1168 	if (!chan->desc_pool &&
1169 	    ((chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA) &&
1170 		chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA)) {
1171 		dev_err(chan->dev,
1172 			"unable to allocate channel %d descriptor pool\n",
1173 			chan->id);
1174 		return -ENOMEM;
1175 	}
1176 
1177 	dma_cookie_init(dchan);
1178 
1179 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1180 		/* For AXI DMA resetting once channel will reset the
1181 		 * other channel as well so enable the interrupts here.
1182 		 */
1183 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1184 			      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1185 	}
1186 
1187 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
1188 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1189 			     XILINX_CDMA_CR_SGMODE);
1190 
1191 	return 0;
1192 }
1193 
1194 /**
1195  * xilinx_dma_calc_copysize - Calculate the amount of data to copy
1196  * @chan: Driver specific DMA channel
1197  * @size: Total data that needs to be copied
1198  * @done: Amount of data that has been already copied
1199  *
1200  * Return: Amount of data that has to be copied
1201  */
1202 static int xilinx_dma_calc_copysize(struct xilinx_dma_chan *chan,
1203 				    int size, int done)
1204 {
1205 	size_t copy;
1206 
1207 	copy = min_t(size_t, size - done,
1208 		     chan->xdev->max_buffer_len);
1209 
1210 	if ((copy + done < size) &&
1211 	    chan->xdev->common.copy_align) {
1212 		/*
1213 		 * If this is not the last descriptor, make sure
1214 		 * the next one will be properly aligned
1215 		 */
1216 		copy = rounddown(copy,
1217 				 (1 << chan->xdev->common.copy_align));
1218 	}
1219 	return copy;
1220 }
1221 
1222 /**
1223  * xilinx_dma_tx_status - Get DMA transaction status
1224  * @dchan: DMA channel
1225  * @cookie: Transaction identifier
1226  * @txstate: Transaction state
1227  *
1228  * Return: DMA transaction status
1229  */
1230 static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
1231 					dma_cookie_t cookie,
1232 					struct dma_tx_state *txstate)
1233 {
1234 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1235 	struct xilinx_dma_tx_descriptor *desc;
1236 	enum dma_status ret;
1237 	unsigned long flags;
1238 	u32 residue = 0;
1239 
1240 	ret = dma_cookie_status(dchan, cookie, txstate);
1241 	if (ret == DMA_COMPLETE || !txstate)
1242 		return ret;
1243 
1244 	spin_lock_irqsave(&chan->lock, flags);
1245 	if (!list_empty(&chan->active_list)) {
1246 		desc = list_last_entry(&chan->active_list,
1247 				       struct xilinx_dma_tx_descriptor, node);
1248 		/*
1249 		 * VDMA and simple mode do not support residue reporting, so the
1250 		 * residue field will always be 0.
1251 		 */
1252 		if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA)
1253 			residue = xilinx_dma_get_residue(chan, desc);
1254 	}
1255 	spin_unlock_irqrestore(&chan->lock, flags);
1256 
1257 	dma_set_residue(txstate, residue);
1258 
1259 	return ret;
1260 }
1261 
1262 /**
1263  * xilinx_dma_stop_transfer - Halt DMA channel
1264  * @chan: Driver specific DMA channel
1265  *
1266  * Return: '0' on success and failure value on error
1267  */
1268 static int xilinx_dma_stop_transfer(struct xilinx_dma_chan *chan)
1269 {
1270 	u32 val;
1271 
1272 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1273 
1274 	/* Wait for the hardware to halt */
1275 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1276 				       val & XILINX_DMA_DMASR_HALTED, 0,
1277 				       XILINX_DMA_LOOP_COUNT);
1278 }
1279 
1280 /**
1281  * xilinx_cdma_stop_transfer - Wait for the current transfer to complete
1282  * @chan: Driver specific DMA channel
1283  *
1284  * Return: '0' on success and failure value on error
1285  */
1286 static int xilinx_cdma_stop_transfer(struct xilinx_dma_chan *chan)
1287 {
1288 	u32 val;
1289 
1290 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1291 				       val & XILINX_DMA_DMASR_IDLE, 0,
1292 				       XILINX_DMA_LOOP_COUNT);
1293 }
1294 
1295 /**
1296  * xilinx_dma_start - Start DMA channel
1297  * @chan: Driver specific DMA channel
1298  */
1299 static void xilinx_dma_start(struct xilinx_dma_chan *chan)
1300 {
1301 	int err;
1302 	u32 val;
1303 
1304 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1305 
1306 	/* Wait for the hardware to start */
1307 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1308 				      !(val & XILINX_DMA_DMASR_HALTED), 0,
1309 				      XILINX_DMA_LOOP_COUNT);
1310 
1311 	if (err) {
1312 		dev_err(chan->dev, "Cannot start channel %p: %x\n",
1313 			chan, dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1314 
1315 		chan->err = true;
1316 	}
1317 }
1318 
1319 /**
1320  * xilinx_vdma_start_transfer - Starts VDMA transfer
1321  * @chan: Driver specific channel struct pointer
1322  */
1323 static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
1324 {
1325 	struct xilinx_vdma_config *config = &chan->config;
1326 	struct xilinx_dma_tx_descriptor *desc;
1327 	u32 reg, j;
1328 	struct xilinx_vdma_tx_segment *segment, *last = NULL;
1329 	int i = 0;
1330 
1331 	/* This function was invoked with lock held */
1332 	if (chan->err)
1333 		return;
1334 
1335 	if (!chan->idle)
1336 		return;
1337 
1338 	if (list_empty(&chan->pending_list))
1339 		return;
1340 
1341 	desc = list_first_entry(&chan->pending_list,
1342 				struct xilinx_dma_tx_descriptor, node);
1343 
1344 	/* Configure the hardware using info in the config structure */
1345 	if (chan->has_vflip) {
1346 		reg = dma_read(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP);
1347 		reg &= ~XILINX_VDMA_ENABLE_VERTICAL_FLIP;
1348 		reg |= config->vflip_en;
1349 		dma_write(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP,
1350 			  reg);
1351 	}
1352 
1353 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1354 
1355 	if (config->frm_cnt_en)
1356 		reg |= XILINX_DMA_DMACR_FRAMECNT_EN;
1357 	else
1358 		reg &= ~XILINX_DMA_DMACR_FRAMECNT_EN;
1359 
1360 	/* If not parking, enable circular mode */
1361 	if (config->park)
1362 		reg &= ~XILINX_DMA_DMACR_CIRC_EN;
1363 	else
1364 		reg |= XILINX_DMA_DMACR_CIRC_EN;
1365 
1366 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1367 
1368 	j = chan->desc_submitcount;
1369 	reg = dma_read(chan, XILINX_DMA_REG_PARK_PTR);
1370 	if (chan->direction == DMA_MEM_TO_DEV) {
1371 		reg &= ~XILINX_DMA_PARK_PTR_RD_REF_MASK;
1372 		reg |= j << XILINX_DMA_PARK_PTR_RD_REF_SHIFT;
1373 	} else {
1374 		reg &= ~XILINX_DMA_PARK_PTR_WR_REF_MASK;
1375 		reg |= j << XILINX_DMA_PARK_PTR_WR_REF_SHIFT;
1376 	}
1377 	dma_write(chan, XILINX_DMA_REG_PARK_PTR, reg);
1378 
1379 	/* Start the hardware */
1380 	xilinx_dma_start(chan);
1381 
1382 	if (chan->err)
1383 		return;
1384 
1385 	/* Start the transfer */
1386 	if (chan->desc_submitcount < chan->num_frms)
1387 		i = chan->desc_submitcount;
1388 
1389 	list_for_each_entry(segment, &desc->segments, node) {
1390 		if (chan->ext_addr)
1391 			vdma_desc_write_64(chan,
1392 				   XILINX_VDMA_REG_START_ADDRESS_64(i++),
1393 				   segment->hw.buf_addr,
1394 				   segment->hw.buf_addr_msb);
1395 		else
1396 			vdma_desc_write(chan,
1397 					XILINX_VDMA_REG_START_ADDRESS(i++),
1398 					segment->hw.buf_addr);
1399 
1400 		last = segment;
1401 	}
1402 
1403 	if (!last)
1404 		return;
1405 
1406 	/* HW expects these parameters to be same for one transaction */
1407 	vdma_desc_write(chan, XILINX_DMA_REG_HSIZE, last->hw.hsize);
1408 	vdma_desc_write(chan, XILINX_DMA_REG_FRMDLY_STRIDE,
1409 			last->hw.stride);
1410 	vdma_desc_write(chan, XILINX_DMA_REG_VSIZE, last->hw.vsize);
1411 
1412 	chan->desc_submitcount++;
1413 	chan->desc_pendingcount--;
1414 	list_del(&desc->node);
1415 	list_add_tail(&desc->node, &chan->active_list);
1416 	if (chan->desc_submitcount == chan->num_frms)
1417 		chan->desc_submitcount = 0;
1418 
1419 	chan->idle = false;
1420 }
1421 
1422 /**
1423  * xilinx_cdma_start_transfer - Starts cdma transfer
1424  * @chan: Driver specific channel struct pointer
1425  */
1426 static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
1427 {
1428 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1429 	struct xilinx_cdma_tx_segment *tail_segment;
1430 	u32 ctrl_reg = dma_read(chan, XILINX_DMA_REG_DMACR);
1431 
1432 	if (chan->err)
1433 		return;
1434 
1435 	if (!chan->idle)
1436 		return;
1437 
1438 	if (list_empty(&chan->pending_list))
1439 		return;
1440 
1441 	head_desc = list_first_entry(&chan->pending_list,
1442 				     struct xilinx_dma_tx_descriptor, node);
1443 	tail_desc = list_last_entry(&chan->pending_list,
1444 				    struct xilinx_dma_tx_descriptor, node);
1445 	tail_segment = list_last_entry(&tail_desc->segments,
1446 				       struct xilinx_cdma_tx_segment, node);
1447 
1448 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1449 		ctrl_reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1450 		ctrl_reg |= chan->desc_pendingcount <<
1451 				XILINX_DMA_CR_COALESCE_SHIFT;
1452 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, ctrl_reg);
1453 	}
1454 
1455 	if (chan->has_sg) {
1456 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
1457 			     XILINX_CDMA_CR_SGMODE);
1458 
1459 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1460 			     XILINX_CDMA_CR_SGMODE);
1461 
1462 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1463 			     head_desc->async_tx.phys);
1464 
1465 		/* Update tail ptr register which will start the transfer */
1466 		xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1467 			     tail_segment->phys);
1468 	} else {
1469 		/* In simple mode */
1470 		struct xilinx_cdma_tx_segment *segment;
1471 		struct xilinx_cdma_desc_hw *hw;
1472 
1473 		segment = list_first_entry(&head_desc->segments,
1474 					   struct xilinx_cdma_tx_segment,
1475 					   node);
1476 
1477 		hw = &segment->hw;
1478 
1479 		xilinx_write(chan, XILINX_CDMA_REG_SRCADDR,
1480 			     xilinx_prep_dma_addr_t(hw->src_addr));
1481 		xilinx_write(chan, XILINX_CDMA_REG_DSTADDR,
1482 			     xilinx_prep_dma_addr_t(hw->dest_addr));
1483 
1484 		/* Start the transfer */
1485 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1486 				hw->control & chan->xdev->max_buffer_len);
1487 	}
1488 
1489 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1490 	chan->desc_pendingcount = 0;
1491 	chan->idle = false;
1492 }
1493 
1494 /**
1495  * xilinx_dma_start_transfer - Starts DMA transfer
1496  * @chan: Driver specific channel struct pointer
1497  */
1498 static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
1499 {
1500 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1501 	struct xilinx_axidma_tx_segment *tail_segment;
1502 	u32 reg;
1503 
1504 	if (chan->err)
1505 		return;
1506 
1507 	if (list_empty(&chan->pending_list))
1508 		return;
1509 
1510 	if (!chan->idle)
1511 		return;
1512 
1513 	head_desc = list_first_entry(&chan->pending_list,
1514 				     struct xilinx_dma_tx_descriptor, node);
1515 	tail_desc = list_last_entry(&chan->pending_list,
1516 				    struct xilinx_dma_tx_descriptor, node);
1517 	tail_segment = list_last_entry(&tail_desc->segments,
1518 				       struct xilinx_axidma_tx_segment, node);
1519 
1520 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1521 
1522 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1523 		reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1524 		reg |= chan->desc_pendingcount <<
1525 				  XILINX_DMA_CR_COALESCE_SHIFT;
1526 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1527 	}
1528 
1529 	if (chan->has_sg)
1530 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1531 			     head_desc->async_tx.phys);
1532 
1533 	xilinx_dma_start(chan);
1534 
1535 	if (chan->err)
1536 		return;
1537 
1538 	/* Start the transfer */
1539 	if (chan->has_sg) {
1540 		if (chan->cyclic)
1541 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1542 				     chan->cyclic_seg_v->phys);
1543 		else
1544 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1545 				     tail_segment->phys);
1546 	} else {
1547 		struct xilinx_axidma_tx_segment *segment;
1548 		struct xilinx_axidma_desc_hw *hw;
1549 
1550 		segment = list_first_entry(&head_desc->segments,
1551 					   struct xilinx_axidma_tx_segment,
1552 					   node);
1553 		hw = &segment->hw;
1554 
1555 		xilinx_write(chan, XILINX_DMA_REG_SRCDSTADDR,
1556 			     xilinx_prep_dma_addr_t(hw->buf_addr));
1557 
1558 		/* Start the transfer */
1559 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1560 			       hw->control & chan->xdev->max_buffer_len);
1561 	}
1562 
1563 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1564 	chan->desc_pendingcount = 0;
1565 	chan->idle = false;
1566 }
1567 
1568 /**
1569  * xilinx_mcdma_start_transfer - Starts MCDMA transfer
1570  * @chan: Driver specific channel struct pointer
1571  */
1572 static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan)
1573 {
1574 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1575 	struct xilinx_aximcdma_tx_segment *tail_segment;
1576 	u32 reg;
1577 
1578 	/*
1579 	 * lock has been held by calling functions, so we don't need it
1580 	 * to take it here again.
1581 	 */
1582 
1583 	if (chan->err)
1584 		return;
1585 
1586 	if (!chan->idle)
1587 		return;
1588 
1589 	if (list_empty(&chan->pending_list))
1590 		return;
1591 
1592 	head_desc = list_first_entry(&chan->pending_list,
1593 				     struct xilinx_dma_tx_descriptor, node);
1594 	tail_desc = list_last_entry(&chan->pending_list,
1595 				    struct xilinx_dma_tx_descriptor, node);
1596 	tail_segment = list_last_entry(&tail_desc->segments,
1597 				       struct xilinx_aximcdma_tx_segment, node);
1598 
1599 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1600 
1601 	if (chan->desc_pendingcount <= XILINX_MCDMA_COALESCE_MAX) {
1602 		reg &= ~XILINX_MCDMA_COALESCE_MASK;
1603 		reg |= chan->desc_pendingcount <<
1604 			XILINX_MCDMA_COALESCE_SHIFT;
1605 	}
1606 
1607 	reg |= XILINX_MCDMA_IRQ_ALL_MASK;
1608 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1609 
1610 	/* Program current descriptor */
1611 	xilinx_write(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET(chan->tdest),
1612 		     head_desc->async_tx.phys);
1613 
1614 	/* Program channel enable register */
1615 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHEN_OFFSET);
1616 	reg |= BIT(chan->tdest);
1617 	dma_ctrl_write(chan, XILINX_MCDMA_CHEN_OFFSET, reg);
1618 
1619 	/* Start the fetch of BDs for the channel */
1620 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1621 	reg |= XILINX_MCDMA_CR_RUNSTOP_MASK;
1622 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1623 
1624 	xilinx_dma_start(chan);
1625 
1626 	if (chan->err)
1627 		return;
1628 
1629 	/* Start the transfer */
1630 	xilinx_write(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET(chan->tdest),
1631 		     tail_segment->phys);
1632 
1633 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1634 	chan->desc_pendingcount = 0;
1635 	chan->idle = false;
1636 }
1637 
1638 /**
1639  * xilinx_dma_issue_pending - Issue pending transactions
1640  * @dchan: DMA channel
1641  */
1642 static void xilinx_dma_issue_pending(struct dma_chan *dchan)
1643 {
1644 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1645 	unsigned long flags;
1646 
1647 	spin_lock_irqsave(&chan->lock, flags);
1648 	chan->start_transfer(chan);
1649 	spin_unlock_irqrestore(&chan->lock, flags);
1650 }
1651 
1652 /**
1653  * xilinx_dma_complete_descriptor - Mark the active descriptor as complete
1654  * @chan : xilinx DMA channel
1655  *
1656  * CONTEXT: hardirq
1657  */
1658 static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
1659 {
1660 	struct xilinx_dma_tx_descriptor *desc, *next;
1661 
1662 	/* This function was invoked with lock held */
1663 	if (list_empty(&chan->active_list))
1664 		return;
1665 
1666 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
1667 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
1668 		    XDMA_TYPE_VDMA)
1669 			desc->residue = xilinx_dma_get_residue(chan, desc);
1670 		else
1671 			desc->residue = 0;
1672 		desc->err = chan->err;
1673 
1674 		list_del(&desc->node);
1675 		if (!desc->cyclic)
1676 			dma_cookie_complete(&desc->async_tx);
1677 		list_add_tail(&desc->node, &chan->done_list);
1678 	}
1679 }
1680 
1681 /**
1682  * xilinx_dma_reset - Reset DMA channel
1683  * @chan: Driver specific DMA channel
1684  *
1685  * Return: '0' on success and failure value on error
1686  */
1687 static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
1688 {
1689 	int err;
1690 	u32 tmp;
1691 
1692 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RESET);
1693 
1694 	/* Wait for the hardware to finish reset */
1695 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMACR, tmp,
1696 				      !(tmp & XILINX_DMA_DMACR_RESET), 0,
1697 				      XILINX_DMA_LOOP_COUNT);
1698 
1699 	if (err) {
1700 		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
1701 			dma_ctrl_read(chan, XILINX_DMA_REG_DMACR),
1702 			dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1703 		return -ETIMEDOUT;
1704 	}
1705 
1706 	chan->err = false;
1707 	chan->idle = true;
1708 	chan->desc_pendingcount = 0;
1709 	chan->desc_submitcount = 0;
1710 
1711 	return err;
1712 }
1713 
1714 /**
1715  * xilinx_dma_chan_reset - Reset DMA channel and enable interrupts
1716  * @chan: Driver specific DMA channel
1717  *
1718  * Return: '0' on success and failure value on error
1719  */
1720 static int xilinx_dma_chan_reset(struct xilinx_dma_chan *chan)
1721 {
1722 	int err;
1723 
1724 	/* Reset VDMA */
1725 	err = xilinx_dma_reset(chan);
1726 	if (err)
1727 		return err;
1728 
1729 	/* Enable interrupts */
1730 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1731 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1732 
1733 	return 0;
1734 }
1735 
1736 /**
1737  * xilinx_mcdma_irq_handler - MCDMA Interrupt handler
1738  * @irq: IRQ number
1739  * @data: Pointer to the Xilinx MCDMA channel structure
1740  *
1741  * Return: IRQ_HANDLED/IRQ_NONE
1742  */
1743 static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
1744 {
1745 	struct xilinx_dma_chan *chan = data;
1746 	u32 status, ser_offset, chan_sermask, chan_offset = 0, chan_id;
1747 
1748 	if (chan->direction == DMA_DEV_TO_MEM)
1749 		ser_offset = XILINX_MCDMA_RXINT_SER_OFFSET;
1750 	else
1751 		ser_offset = XILINX_MCDMA_TXINT_SER_OFFSET;
1752 
1753 	/* Read the channel id raising the interrupt*/
1754 	chan_sermask = dma_ctrl_read(chan, ser_offset);
1755 	chan_id = ffs(chan_sermask);
1756 
1757 	if (!chan_id)
1758 		return IRQ_NONE;
1759 
1760 	if (chan->direction == DMA_DEV_TO_MEM)
1761 		chan_offset = chan->xdev->dma_config->max_channels / 2;
1762 
1763 	chan_offset = chan_offset + (chan_id - 1);
1764 	chan = chan->xdev->chan[chan_offset];
1765 	/* Read the status and ack the interrupts. */
1766 	status = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest));
1767 	if (!(status & XILINX_MCDMA_IRQ_ALL_MASK))
1768 		return IRQ_NONE;
1769 
1770 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest),
1771 		       status & XILINX_MCDMA_IRQ_ALL_MASK);
1772 
1773 	if (status & XILINX_MCDMA_IRQ_ERR_MASK) {
1774 		dev_err(chan->dev, "Channel %p has errors %x cdr %x tdr %x\n",
1775 			chan,
1776 			dma_ctrl_read(chan, XILINX_MCDMA_CH_ERR_OFFSET),
1777 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET
1778 				      (chan->tdest)),
1779 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET
1780 				      (chan->tdest)));
1781 		chan->err = true;
1782 	}
1783 
1784 	if (status & XILINX_MCDMA_IRQ_DELAY_MASK) {
1785 		/*
1786 		 * Device takes too long to do the transfer when user requires
1787 		 * responsiveness.
1788 		 */
1789 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1790 	}
1791 
1792 	if (status & XILINX_MCDMA_IRQ_IOC_MASK) {
1793 		spin_lock(&chan->lock);
1794 		xilinx_dma_complete_descriptor(chan);
1795 		chan->idle = true;
1796 		chan->start_transfer(chan);
1797 		spin_unlock(&chan->lock);
1798 	}
1799 
1800 	tasklet_schedule(&chan->tasklet);
1801 	return IRQ_HANDLED;
1802 }
1803 
1804 /**
1805  * xilinx_dma_irq_handler - DMA Interrupt handler
1806  * @irq: IRQ number
1807  * @data: Pointer to the Xilinx DMA channel structure
1808  *
1809  * Return: IRQ_HANDLED/IRQ_NONE
1810  */
1811 static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
1812 {
1813 	struct xilinx_dma_chan *chan = data;
1814 	u32 status;
1815 
1816 	/* Read the status and ack the interrupts. */
1817 	status = dma_ctrl_read(chan, XILINX_DMA_REG_DMASR);
1818 	if (!(status & XILINX_DMA_DMAXR_ALL_IRQ_MASK))
1819 		return IRQ_NONE;
1820 
1821 	dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1822 			status & XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1823 
1824 	if (status & XILINX_DMA_DMASR_ERR_IRQ) {
1825 		/*
1826 		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
1827 		 * error is recoverable, ignore it. Otherwise flag the error.
1828 		 *
1829 		 * Only recoverable errors can be cleared in the DMASR register,
1830 		 * make sure not to write to other error bits to 1.
1831 		 */
1832 		u32 errors = status & XILINX_DMA_DMASR_ALL_ERR_MASK;
1833 
1834 		dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1835 				errors & XILINX_DMA_DMASR_ERR_RECOVER_MASK);
1836 
1837 		if (!chan->flush_on_fsync ||
1838 		    (errors & ~XILINX_DMA_DMASR_ERR_RECOVER_MASK)) {
1839 			dev_err(chan->dev,
1840 				"Channel %p has errors %x, cdr %x tdr %x\n",
1841 				chan, errors,
1842 				dma_ctrl_read(chan, XILINX_DMA_REG_CURDESC),
1843 				dma_ctrl_read(chan, XILINX_DMA_REG_TAILDESC));
1844 			chan->err = true;
1845 		}
1846 	}
1847 
1848 	if (status & XILINX_DMA_DMASR_DLY_CNT_IRQ) {
1849 		/*
1850 		 * Device takes too long to do the transfer when user requires
1851 		 * responsiveness.
1852 		 */
1853 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1854 	}
1855 
1856 	if (status & XILINX_DMA_DMASR_FRM_CNT_IRQ) {
1857 		spin_lock(&chan->lock);
1858 		xilinx_dma_complete_descriptor(chan);
1859 		chan->idle = true;
1860 		chan->start_transfer(chan);
1861 		spin_unlock(&chan->lock);
1862 	}
1863 
1864 	tasklet_schedule(&chan->tasklet);
1865 	return IRQ_HANDLED;
1866 }
1867 
1868 /**
1869  * append_desc_queue - Queuing descriptor
1870  * @chan: Driver specific dma channel
1871  * @desc: dma transaction descriptor
1872  */
1873 static void append_desc_queue(struct xilinx_dma_chan *chan,
1874 			      struct xilinx_dma_tx_descriptor *desc)
1875 {
1876 	struct xilinx_vdma_tx_segment *tail_segment;
1877 	struct xilinx_dma_tx_descriptor *tail_desc;
1878 	struct xilinx_axidma_tx_segment *axidma_tail_segment;
1879 	struct xilinx_aximcdma_tx_segment *aximcdma_tail_segment;
1880 	struct xilinx_cdma_tx_segment *cdma_tail_segment;
1881 
1882 	if (list_empty(&chan->pending_list))
1883 		goto append;
1884 
1885 	/*
1886 	 * Add the hardware descriptor to the chain of hardware descriptors
1887 	 * that already exists in memory.
1888 	 */
1889 	tail_desc = list_last_entry(&chan->pending_list,
1890 				    struct xilinx_dma_tx_descriptor, node);
1891 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
1892 		tail_segment = list_last_entry(&tail_desc->segments,
1893 					       struct xilinx_vdma_tx_segment,
1894 					       node);
1895 		tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1896 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1897 		cdma_tail_segment = list_last_entry(&tail_desc->segments,
1898 						struct xilinx_cdma_tx_segment,
1899 						node);
1900 		cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1901 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1902 		axidma_tail_segment = list_last_entry(&tail_desc->segments,
1903 					       struct xilinx_axidma_tx_segment,
1904 					       node);
1905 		axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1906 	} else {
1907 		aximcdma_tail_segment =
1908 			list_last_entry(&tail_desc->segments,
1909 					struct xilinx_aximcdma_tx_segment,
1910 					node);
1911 		aximcdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1912 	}
1913 
1914 	/*
1915 	 * Add the software descriptor and all children to the list
1916 	 * of pending transactions
1917 	 */
1918 append:
1919 	list_add_tail(&desc->node, &chan->pending_list);
1920 	chan->desc_pendingcount++;
1921 
1922 	if (chan->has_sg && (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA)
1923 	    && unlikely(chan->desc_pendingcount > chan->num_frms)) {
1924 		dev_dbg(chan->dev, "desc pendingcount is too high\n");
1925 		chan->desc_pendingcount = chan->num_frms;
1926 	}
1927 }
1928 
1929 /**
1930  * xilinx_dma_tx_submit - Submit DMA transaction
1931  * @tx: Async transaction descriptor
1932  *
1933  * Return: cookie value on success and failure value on error
1934  */
1935 static dma_cookie_t xilinx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
1936 {
1937 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
1938 	struct xilinx_dma_chan *chan = to_xilinx_chan(tx->chan);
1939 	dma_cookie_t cookie;
1940 	unsigned long flags;
1941 	int err;
1942 
1943 	if (chan->cyclic) {
1944 		xilinx_dma_free_tx_descriptor(chan, desc);
1945 		return -EBUSY;
1946 	}
1947 
1948 	if (chan->err) {
1949 		/*
1950 		 * If reset fails, need to hard reset the system.
1951 		 * Channel is no longer functional
1952 		 */
1953 		err = xilinx_dma_chan_reset(chan);
1954 		if (err < 0)
1955 			return err;
1956 	}
1957 
1958 	spin_lock_irqsave(&chan->lock, flags);
1959 
1960 	cookie = dma_cookie_assign(tx);
1961 
1962 	/* Put this transaction onto the tail of the pending queue */
1963 	append_desc_queue(chan, desc);
1964 
1965 	if (desc->cyclic)
1966 		chan->cyclic = true;
1967 
1968 	spin_unlock_irqrestore(&chan->lock, flags);
1969 
1970 	return cookie;
1971 }
1972 
1973 /**
1974  * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
1975  *	DMA_SLAVE transaction
1976  * @dchan: DMA channel
1977  * @xt: Interleaved template pointer
1978  * @flags: transfer ack flags
1979  *
1980  * Return: Async transaction descriptor on success and NULL on failure
1981  */
1982 static struct dma_async_tx_descriptor *
1983 xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
1984 				 struct dma_interleaved_template *xt,
1985 				 unsigned long flags)
1986 {
1987 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1988 	struct xilinx_dma_tx_descriptor *desc;
1989 	struct xilinx_vdma_tx_segment *segment;
1990 	struct xilinx_vdma_desc_hw *hw;
1991 
1992 	if (!is_slave_direction(xt->dir))
1993 		return NULL;
1994 
1995 	if (!xt->numf || !xt->sgl[0].size)
1996 		return NULL;
1997 
1998 	if (xt->frame_size != 1)
1999 		return NULL;
2000 
2001 	/* Allocate a transaction descriptor. */
2002 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2003 	if (!desc)
2004 		return NULL;
2005 
2006 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2007 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2008 	async_tx_ack(&desc->async_tx);
2009 
2010 	/* Allocate the link descriptor from DMA pool */
2011 	segment = xilinx_vdma_alloc_tx_segment(chan);
2012 	if (!segment)
2013 		goto error;
2014 
2015 	/* Fill in the hardware descriptor */
2016 	hw = &segment->hw;
2017 	hw->vsize = xt->numf;
2018 	hw->hsize = xt->sgl[0].size;
2019 	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
2020 			XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT;
2021 	hw->stride |= chan->config.frm_dly <<
2022 			XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
2023 
2024 	if (xt->dir != DMA_MEM_TO_DEV) {
2025 		if (chan->ext_addr) {
2026 			hw->buf_addr = lower_32_bits(xt->dst_start);
2027 			hw->buf_addr_msb = upper_32_bits(xt->dst_start);
2028 		} else {
2029 			hw->buf_addr = xt->dst_start;
2030 		}
2031 	} else {
2032 		if (chan->ext_addr) {
2033 			hw->buf_addr = lower_32_bits(xt->src_start);
2034 			hw->buf_addr_msb = upper_32_bits(xt->src_start);
2035 		} else {
2036 			hw->buf_addr = xt->src_start;
2037 		}
2038 	}
2039 
2040 	/* Insert the segment into the descriptor segments list. */
2041 	list_add_tail(&segment->node, &desc->segments);
2042 
2043 	/* Link the last hardware descriptor with the first. */
2044 	segment = list_first_entry(&desc->segments,
2045 				   struct xilinx_vdma_tx_segment, node);
2046 	desc->async_tx.phys = segment->phys;
2047 
2048 	return &desc->async_tx;
2049 
2050 error:
2051 	xilinx_dma_free_tx_descriptor(chan, desc);
2052 	return NULL;
2053 }
2054 
2055 /**
2056  * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
2057  * @dchan: DMA channel
2058  * @dma_dst: destination address
2059  * @dma_src: source address
2060  * @len: transfer length
2061  * @flags: transfer ack flags
2062  *
2063  * Return: Async transaction descriptor on success and NULL on failure
2064  */
2065 static struct dma_async_tx_descriptor *
2066 xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
2067 			dma_addr_t dma_src, size_t len, unsigned long flags)
2068 {
2069 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2070 	struct xilinx_dma_tx_descriptor *desc;
2071 	struct xilinx_cdma_tx_segment *segment;
2072 	struct xilinx_cdma_desc_hw *hw;
2073 
2074 	if (!len || len > chan->xdev->max_buffer_len)
2075 		return NULL;
2076 
2077 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2078 	if (!desc)
2079 		return NULL;
2080 
2081 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2082 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2083 
2084 	/* Allocate the link descriptor from DMA pool */
2085 	segment = xilinx_cdma_alloc_tx_segment(chan);
2086 	if (!segment)
2087 		goto error;
2088 
2089 	hw = &segment->hw;
2090 	hw->control = len;
2091 	hw->src_addr = dma_src;
2092 	hw->dest_addr = dma_dst;
2093 	if (chan->ext_addr) {
2094 		hw->src_addr_msb = upper_32_bits(dma_src);
2095 		hw->dest_addr_msb = upper_32_bits(dma_dst);
2096 	}
2097 
2098 	/* Insert the segment into the descriptor segments list. */
2099 	list_add_tail(&segment->node, &desc->segments);
2100 
2101 	desc->async_tx.phys = segment->phys;
2102 	hw->next_desc = segment->phys;
2103 
2104 	return &desc->async_tx;
2105 
2106 error:
2107 	xilinx_dma_free_tx_descriptor(chan, desc);
2108 	return NULL;
2109 }
2110 
2111 /**
2112  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2113  * @dchan: DMA channel
2114  * @sgl: scatterlist to transfer to/from
2115  * @sg_len: number of entries in @scatterlist
2116  * @direction: DMA direction
2117  * @flags: transfer ack flags
2118  * @context: APP words of the descriptor
2119  *
2120  * Return: Async transaction descriptor on success and NULL on failure
2121  */
2122 static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
2123 	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
2124 	enum dma_transfer_direction direction, unsigned long flags,
2125 	void *context)
2126 {
2127 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2128 	struct xilinx_dma_tx_descriptor *desc;
2129 	struct xilinx_axidma_tx_segment *segment = NULL;
2130 	u32 *app_w = (u32 *)context;
2131 	struct scatterlist *sg;
2132 	size_t copy;
2133 	size_t sg_used;
2134 	unsigned int i;
2135 
2136 	if (!is_slave_direction(direction))
2137 		return NULL;
2138 
2139 	/* Allocate a transaction descriptor. */
2140 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2141 	if (!desc)
2142 		return NULL;
2143 
2144 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2145 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2146 
2147 	/* Build transactions using information in the scatter gather list */
2148 	for_each_sg(sgl, sg, sg_len, i) {
2149 		sg_used = 0;
2150 
2151 		/* Loop until the entire scatterlist entry is used */
2152 		while (sg_used < sg_dma_len(sg)) {
2153 			struct xilinx_axidma_desc_hw *hw;
2154 
2155 			/* Get a free segment */
2156 			segment = xilinx_axidma_alloc_tx_segment(chan);
2157 			if (!segment)
2158 				goto error;
2159 
2160 			/*
2161 			 * Calculate the maximum number of bytes to transfer,
2162 			 * making sure it is less than the hw limit
2163 			 */
2164 			copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
2165 							sg_used);
2166 			hw = &segment->hw;
2167 
2168 			/* Fill in the descriptor */
2169 			xilinx_axidma_buf(chan, hw, sg_dma_address(sg),
2170 					  sg_used, 0);
2171 
2172 			hw->control = copy;
2173 
2174 			if (chan->direction == DMA_MEM_TO_DEV) {
2175 				if (app_w)
2176 					memcpy(hw->app, app_w, sizeof(u32) *
2177 					       XILINX_DMA_NUM_APP_WORDS);
2178 			}
2179 
2180 			sg_used += copy;
2181 
2182 			/*
2183 			 * Insert the segment into the descriptor segments
2184 			 * list.
2185 			 */
2186 			list_add_tail(&segment->node, &desc->segments);
2187 		}
2188 	}
2189 
2190 	segment = list_first_entry(&desc->segments,
2191 				   struct xilinx_axidma_tx_segment, node);
2192 	desc->async_tx.phys = segment->phys;
2193 
2194 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2195 	if (chan->direction == DMA_MEM_TO_DEV) {
2196 		segment->hw.control |= XILINX_DMA_BD_SOP;
2197 		segment = list_last_entry(&desc->segments,
2198 					  struct xilinx_axidma_tx_segment,
2199 					  node);
2200 		segment->hw.control |= XILINX_DMA_BD_EOP;
2201 	}
2202 
2203 	return &desc->async_tx;
2204 
2205 error:
2206 	xilinx_dma_free_tx_descriptor(chan, desc);
2207 	return NULL;
2208 }
2209 
2210 /**
2211  * xilinx_dma_prep_dma_cyclic - prepare descriptors for a DMA_SLAVE transaction
2212  * @dchan: DMA channel
2213  * @buf_addr: Physical address of the buffer
2214  * @buf_len: Total length of the cyclic buffers
2215  * @period_len: length of individual cyclic buffer
2216  * @direction: DMA direction
2217  * @flags: transfer ack flags
2218  *
2219  * Return: Async transaction descriptor on success and NULL on failure
2220  */
2221 static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
2222 	struct dma_chan *dchan, dma_addr_t buf_addr, size_t buf_len,
2223 	size_t period_len, enum dma_transfer_direction direction,
2224 	unsigned long flags)
2225 {
2226 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2227 	struct xilinx_dma_tx_descriptor *desc;
2228 	struct xilinx_axidma_tx_segment *segment, *head_segment, *prev = NULL;
2229 	size_t copy, sg_used;
2230 	unsigned int num_periods;
2231 	int i;
2232 	u32 reg;
2233 
2234 	if (!period_len)
2235 		return NULL;
2236 
2237 	num_periods = buf_len / period_len;
2238 
2239 	if (!num_periods)
2240 		return NULL;
2241 
2242 	if (!is_slave_direction(direction))
2243 		return NULL;
2244 
2245 	/* Allocate a transaction descriptor. */
2246 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2247 	if (!desc)
2248 		return NULL;
2249 
2250 	chan->direction = direction;
2251 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2252 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2253 
2254 	for (i = 0; i < num_periods; ++i) {
2255 		sg_used = 0;
2256 
2257 		while (sg_used < period_len) {
2258 			struct xilinx_axidma_desc_hw *hw;
2259 
2260 			/* Get a free segment */
2261 			segment = xilinx_axidma_alloc_tx_segment(chan);
2262 			if (!segment)
2263 				goto error;
2264 
2265 			/*
2266 			 * Calculate the maximum number of bytes to transfer,
2267 			 * making sure it is less than the hw limit
2268 			 */
2269 			copy = xilinx_dma_calc_copysize(chan, period_len,
2270 							sg_used);
2271 			hw = &segment->hw;
2272 			xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
2273 					  period_len * i);
2274 			hw->control = copy;
2275 
2276 			if (prev)
2277 				prev->hw.next_desc = segment->phys;
2278 
2279 			prev = segment;
2280 			sg_used += copy;
2281 
2282 			/*
2283 			 * Insert the segment into the descriptor segments
2284 			 * list.
2285 			 */
2286 			list_add_tail(&segment->node, &desc->segments);
2287 		}
2288 	}
2289 
2290 	head_segment = list_first_entry(&desc->segments,
2291 				   struct xilinx_axidma_tx_segment, node);
2292 	desc->async_tx.phys = head_segment->phys;
2293 
2294 	desc->cyclic = true;
2295 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2296 	reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2297 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2298 
2299 	segment = list_last_entry(&desc->segments,
2300 				  struct xilinx_axidma_tx_segment,
2301 				  node);
2302 	segment->hw.next_desc = (u32) head_segment->phys;
2303 
2304 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2305 	if (direction == DMA_MEM_TO_DEV) {
2306 		head_segment->hw.control |= XILINX_DMA_BD_SOP;
2307 		segment->hw.control |= XILINX_DMA_BD_EOP;
2308 	}
2309 
2310 	return &desc->async_tx;
2311 
2312 error:
2313 	xilinx_dma_free_tx_descriptor(chan, desc);
2314 	return NULL;
2315 }
2316 
2317 /**
2318  * xilinx_mcdma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2319  * @dchan: DMA channel
2320  * @sgl: scatterlist to transfer to/from
2321  * @sg_len: number of entries in @scatterlist
2322  * @direction: DMA direction
2323  * @flags: transfer ack flags
2324  * @context: APP words of the descriptor
2325  *
2326  * Return: Async transaction descriptor on success and NULL on failure
2327  */
2328 static struct dma_async_tx_descriptor *
2329 xilinx_mcdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
2330 			   unsigned int sg_len,
2331 			   enum dma_transfer_direction direction,
2332 			   unsigned long flags, void *context)
2333 {
2334 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2335 	struct xilinx_dma_tx_descriptor *desc;
2336 	struct xilinx_aximcdma_tx_segment *segment = NULL;
2337 	u32 *app_w = (u32 *)context;
2338 	struct scatterlist *sg;
2339 	size_t copy;
2340 	size_t sg_used;
2341 	unsigned int i;
2342 
2343 	if (!is_slave_direction(direction))
2344 		return NULL;
2345 
2346 	/* Allocate a transaction descriptor. */
2347 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2348 	if (!desc)
2349 		return NULL;
2350 
2351 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2352 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2353 
2354 	/* Build transactions using information in the scatter gather list */
2355 	for_each_sg(sgl, sg, sg_len, i) {
2356 		sg_used = 0;
2357 
2358 		/* Loop until the entire scatterlist entry is used */
2359 		while (sg_used < sg_dma_len(sg)) {
2360 			struct xilinx_aximcdma_desc_hw *hw;
2361 
2362 			/* Get a free segment */
2363 			segment = xilinx_aximcdma_alloc_tx_segment(chan);
2364 			if (!segment)
2365 				goto error;
2366 
2367 			/*
2368 			 * Calculate the maximum number of bytes to transfer,
2369 			 * making sure it is less than the hw limit
2370 			 */
2371 			copy = min_t(size_t, sg_dma_len(sg) - sg_used,
2372 				     chan->xdev->max_buffer_len);
2373 			hw = &segment->hw;
2374 
2375 			/* Fill in the descriptor */
2376 			xilinx_aximcdma_buf(chan, hw, sg_dma_address(sg),
2377 					    sg_used);
2378 			hw->control = copy;
2379 
2380 			if (chan->direction == DMA_MEM_TO_DEV && app_w) {
2381 				memcpy(hw->app, app_w, sizeof(u32) *
2382 				       XILINX_DMA_NUM_APP_WORDS);
2383 			}
2384 
2385 			sg_used += copy;
2386 			/*
2387 			 * Insert the segment into the descriptor segments
2388 			 * list.
2389 			 */
2390 			list_add_tail(&segment->node, &desc->segments);
2391 		}
2392 	}
2393 
2394 	segment = list_first_entry(&desc->segments,
2395 				   struct xilinx_aximcdma_tx_segment, node);
2396 	desc->async_tx.phys = segment->phys;
2397 
2398 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2399 	if (chan->direction == DMA_MEM_TO_DEV) {
2400 		segment->hw.control |= XILINX_MCDMA_BD_SOP;
2401 		segment = list_last_entry(&desc->segments,
2402 					  struct xilinx_aximcdma_tx_segment,
2403 					  node);
2404 		segment->hw.control |= XILINX_MCDMA_BD_EOP;
2405 	}
2406 
2407 	return &desc->async_tx;
2408 
2409 error:
2410 	xilinx_dma_free_tx_descriptor(chan, desc);
2411 
2412 	return NULL;
2413 }
2414 
2415 /**
2416  * xilinx_dma_terminate_all - Halt the channel and free descriptors
2417  * @dchan: Driver specific DMA Channel pointer
2418  *
2419  * Return: '0' always.
2420  */
2421 static int xilinx_dma_terminate_all(struct dma_chan *dchan)
2422 {
2423 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2424 	u32 reg;
2425 	int err;
2426 
2427 	if (!chan->cyclic) {
2428 		err = chan->stop_transfer(chan);
2429 		if (err) {
2430 			dev_err(chan->dev, "Cannot stop channel %p: %x\n",
2431 				chan, dma_ctrl_read(chan,
2432 				XILINX_DMA_REG_DMASR));
2433 			chan->err = true;
2434 		}
2435 	}
2436 
2437 	xilinx_dma_chan_reset(chan);
2438 	/* Remove and free all of the descriptors in the lists */
2439 	xilinx_dma_free_descriptors(chan);
2440 	chan->idle = true;
2441 
2442 	if (chan->cyclic) {
2443 		reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2444 		reg &= ~XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2445 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2446 		chan->cyclic = false;
2447 	}
2448 
2449 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
2450 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2451 			     XILINX_CDMA_CR_SGMODE);
2452 
2453 	return 0;
2454 }
2455 
2456 /**
2457  * xilinx_dma_channel_set_config - Configure VDMA channel
2458  * Run-time configuration for Axi VDMA, supports:
2459  * . halt the channel
2460  * . configure interrupt coalescing and inter-packet delay threshold
2461  * . start/stop parking
2462  * . enable genlock
2463  *
2464  * @dchan: DMA channel
2465  * @cfg: VDMA device configuration pointer
2466  *
2467  * Return: '0' on success and failure value on error
2468  */
2469 int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
2470 					struct xilinx_vdma_config *cfg)
2471 {
2472 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2473 	u32 dmacr;
2474 
2475 	if (cfg->reset)
2476 		return xilinx_dma_chan_reset(chan);
2477 
2478 	dmacr = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2479 
2480 	chan->config.frm_dly = cfg->frm_dly;
2481 	chan->config.park = cfg->park;
2482 
2483 	/* genlock settings */
2484 	chan->config.gen_lock = cfg->gen_lock;
2485 	chan->config.master = cfg->master;
2486 
2487 	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
2488 	if (cfg->gen_lock && chan->genlock) {
2489 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
2490 		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
2491 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
2492 	}
2493 
2494 	chan->config.frm_cnt_en = cfg->frm_cnt_en;
2495 	chan->config.vflip_en = cfg->vflip_en;
2496 
2497 	if (cfg->park)
2498 		chan->config.park_frm = cfg->park_frm;
2499 	else
2500 		chan->config.park_frm = -1;
2501 
2502 	chan->config.coalesc = cfg->coalesc;
2503 	chan->config.delay = cfg->delay;
2504 
2505 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
2506 		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
2507 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
2508 		chan->config.coalesc = cfg->coalesc;
2509 	}
2510 
2511 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
2512 		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
2513 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
2514 		chan->config.delay = cfg->delay;
2515 	}
2516 
2517 	/* FSync Source selection */
2518 	dmacr &= ~XILINX_DMA_DMACR_FSYNCSRC_MASK;
2519 	dmacr |= cfg->ext_fsync << XILINX_DMA_DMACR_FSYNCSRC_SHIFT;
2520 
2521 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, dmacr);
2522 
2523 	return 0;
2524 }
2525 EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
2526 
2527 /* -----------------------------------------------------------------------------
2528  * Probe and remove
2529  */
2530 
2531 /**
2532  * xilinx_dma_chan_remove - Per Channel remove function
2533  * @chan: Driver specific DMA channel
2534  */
2535 static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
2536 {
2537 	/* Disable all interrupts */
2538 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2539 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
2540 
2541 	if (chan->irq > 0)
2542 		free_irq(chan->irq, chan);
2543 
2544 	tasklet_kill(&chan->tasklet);
2545 
2546 	list_del(&chan->common.device_node);
2547 }
2548 
2549 static int axidma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2550 			    struct clk **tx_clk, struct clk **rx_clk,
2551 			    struct clk **sg_clk, struct clk **tmp_clk)
2552 {
2553 	int err;
2554 
2555 	*tmp_clk = NULL;
2556 
2557 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2558 	if (IS_ERR(*axi_clk))
2559 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2560 
2561 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2562 	if (IS_ERR(*tx_clk))
2563 		*tx_clk = NULL;
2564 
2565 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2566 	if (IS_ERR(*rx_clk))
2567 		*rx_clk = NULL;
2568 
2569 	*sg_clk = devm_clk_get(&pdev->dev, "m_axi_sg_aclk");
2570 	if (IS_ERR(*sg_clk))
2571 		*sg_clk = NULL;
2572 
2573 	err = clk_prepare_enable(*axi_clk);
2574 	if (err) {
2575 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2576 		return err;
2577 	}
2578 
2579 	err = clk_prepare_enable(*tx_clk);
2580 	if (err) {
2581 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2582 		goto err_disable_axiclk;
2583 	}
2584 
2585 	err = clk_prepare_enable(*rx_clk);
2586 	if (err) {
2587 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2588 		goto err_disable_txclk;
2589 	}
2590 
2591 	err = clk_prepare_enable(*sg_clk);
2592 	if (err) {
2593 		dev_err(&pdev->dev, "failed to enable sg_clk (%d)\n", err);
2594 		goto err_disable_rxclk;
2595 	}
2596 
2597 	return 0;
2598 
2599 err_disable_rxclk:
2600 	clk_disable_unprepare(*rx_clk);
2601 err_disable_txclk:
2602 	clk_disable_unprepare(*tx_clk);
2603 err_disable_axiclk:
2604 	clk_disable_unprepare(*axi_clk);
2605 
2606 	return err;
2607 }
2608 
2609 static int axicdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2610 			    struct clk **dev_clk, struct clk **tmp_clk,
2611 			    struct clk **tmp1_clk, struct clk **tmp2_clk)
2612 {
2613 	int err;
2614 
2615 	*tmp_clk = NULL;
2616 	*tmp1_clk = NULL;
2617 	*tmp2_clk = NULL;
2618 
2619 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2620 	if (IS_ERR(*axi_clk))
2621 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2622 
2623 	*dev_clk = devm_clk_get(&pdev->dev, "m_axi_aclk");
2624 	if (IS_ERR(*dev_clk))
2625 		return dev_err_probe(&pdev->dev, PTR_ERR(*dev_clk), "failed to get dev_clk\n");
2626 
2627 	err = clk_prepare_enable(*axi_clk);
2628 	if (err) {
2629 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2630 		return err;
2631 	}
2632 
2633 	err = clk_prepare_enable(*dev_clk);
2634 	if (err) {
2635 		dev_err(&pdev->dev, "failed to enable dev_clk (%d)\n", err);
2636 		goto err_disable_axiclk;
2637 	}
2638 
2639 	return 0;
2640 
2641 err_disable_axiclk:
2642 	clk_disable_unprepare(*axi_clk);
2643 
2644 	return err;
2645 }
2646 
2647 static int axivdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2648 			    struct clk **tx_clk, struct clk **txs_clk,
2649 			    struct clk **rx_clk, struct clk **rxs_clk)
2650 {
2651 	int err;
2652 
2653 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2654 	if (IS_ERR(*axi_clk))
2655 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2656 
2657 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2658 	if (IS_ERR(*tx_clk))
2659 		*tx_clk = NULL;
2660 
2661 	*txs_clk = devm_clk_get(&pdev->dev, "m_axis_mm2s_aclk");
2662 	if (IS_ERR(*txs_clk))
2663 		*txs_clk = NULL;
2664 
2665 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2666 	if (IS_ERR(*rx_clk))
2667 		*rx_clk = NULL;
2668 
2669 	*rxs_clk = devm_clk_get(&pdev->dev, "s_axis_s2mm_aclk");
2670 	if (IS_ERR(*rxs_clk))
2671 		*rxs_clk = NULL;
2672 
2673 	err = clk_prepare_enable(*axi_clk);
2674 	if (err) {
2675 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n",
2676 			err);
2677 		return err;
2678 	}
2679 
2680 	err = clk_prepare_enable(*tx_clk);
2681 	if (err) {
2682 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2683 		goto err_disable_axiclk;
2684 	}
2685 
2686 	err = clk_prepare_enable(*txs_clk);
2687 	if (err) {
2688 		dev_err(&pdev->dev, "failed to enable txs_clk (%d)\n", err);
2689 		goto err_disable_txclk;
2690 	}
2691 
2692 	err = clk_prepare_enable(*rx_clk);
2693 	if (err) {
2694 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2695 		goto err_disable_txsclk;
2696 	}
2697 
2698 	err = clk_prepare_enable(*rxs_clk);
2699 	if (err) {
2700 		dev_err(&pdev->dev, "failed to enable rxs_clk (%d)\n", err);
2701 		goto err_disable_rxclk;
2702 	}
2703 
2704 	return 0;
2705 
2706 err_disable_rxclk:
2707 	clk_disable_unprepare(*rx_clk);
2708 err_disable_txsclk:
2709 	clk_disable_unprepare(*txs_clk);
2710 err_disable_txclk:
2711 	clk_disable_unprepare(*tx_clk);
2712 err_disable_axiclk:
2713 	clk_disable_unprepare(*axi_clk);
2714 
2715 	return err;
2716 }
2717 
2718 static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
2719 {
2720 	clk_disable_unprepare(xdev->rxs_clk);
2721 	clk_disable_unprepare(xdev->rx_clk);
2722 	clk_disable_unprepare(xdev->txs_clk);
2723 	clk_disable_unprepare(xdev->tx_clk);
2724 	clk_disable_unprepare(xdev->axi_clk);
2725 }
2726 
2727 /**
2728  * xilinx_dma_chan_probe - Per Channel Probing
2729  * It get channel features from the device tree entry and
2730  * initialize special channel handling routines
2731  *
2732  * @xdev: Driver specific device structure
2733  * @node: Device node
2734  *
2735  * Return: '0' on success and failure value on error
2736  */
2737 static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
2738 				  struct device_node *node)
2739 {
2740 	struct xilinx_dma_chan *chan;
2741 	bool has_dre = false;
2742 	u32 value, width;
2743 	int err;
2744 
2745 	/* Allocate and initialize the channel structure */
2746 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
2747 	if (!chan)
2748 		return -ENOMEM;
2749 
2750 	chan->dev = xdev->dev;
2751 	chan->xdev = xdev;
2752 	chan->desc_pendingcount = 0x0;
2753 	chan->ext_addr = xdev->ext_addr;
2754 	/* This variable ensures that descriptors are not
2755 	 * Submitted when dma engine is in progress. This variable is
2756 	 * Added to avoid polling for a bit in the status register to
2757 	 * Know dma state in the driver hot path.
2758 	 */
2759 	chan->idle = true;
2760 
2761 	spin_lock_init(&chan->lock);
2762 	INIT_LIST_HEAD(&chan->pending_list);
2763 	INIT_LIST_HEAD(&chan->done_list);
2764 	INIT_LIST_HEAD(&chan->active_list);
2765 	INIT_LIST_HEAD(&chan->free_seg_list);
2766 
2767 	/* Retrieve the channel properties from the device tree */
2768 	has_dre = of_property_read_bool(node, "xlnx,include-dre");
2769 
2770 	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
2771 
2772 	err = of_property_read_u32(node, "xlnx,datawidth", &value);
2773 	if (err) {
2774 		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
2775 		return err;
2776 	}
2777 	width = value >> 3; /* Convert bits to bytes */
2778 
2779 	/* If data width is greater than 8 bytes, DRE is not in hw */
2780 	if (width > 8)
2781 		has_dre = false;
2782 
2783 	if (!has_dre)
2784 		xdev->common.copy_align = (enum dmaengine_alignment)fls(width - 1);
2785 
2786 	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel") ||
2787 	    of_device_is_compatible(node, "xlnx,axi-dma-mm2s-channel") ||
2788 	    of_device_is_compatible(node, "xlnx,axi-cdma-channel")) {
2789 		chan->direction = DMA_MEM_TO_DEV;
2790 		chan->id = xdev->mm2s_chan_id++;
2791 		chan->tdest = chan->id;
2792 
2793 		chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
2794 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2795 			chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
2796 			chan->config.park = 1;
2797 
2798 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2799 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
2800 				chan->flush_on_fsync = true;
2801 		}
2802 	} else if (of_device_is_compatible(node,
2803 					   "xlnx,axi-vdma-s2mm-channel") ||
2804 		   of_device_is_compatible(node,
2805 					   "xlnx,axi-dma-s2mm-channel")) {
2806 		chan->direction = DMA_DEV_TO_MEM;
2807 		chan->id = xdev->s2mm_chan_id++;
2808 		chan->tdest = chan->id - xdev->dma_config->max_channels / 2;
2809 		chan->has_vflip = of_property_read_bool(node,
2810 					"xlnx,enable-vert-flip");
2811 		if (chan->has_vflip) {
2812 			chan->config.vflip_en = dma_read(chan,
2813 				XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP) &
2814 				XILINX_VDMA_ENABLE_VERTICAL_FLIP;
2815 		}
2816 
2817 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
2818 			chan->ctrl_offset = XILINX_MCDMA_S2MM_CTRL_OFFSET;
2819 		else
2820 			chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
2821 
2822 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2823 			chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
2824 			chan->config.park = 1;
2825 
2826 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2827 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
2828 				chan->flush_on_fsync = true;
2829 		}
2830 	} else {
2831 		dev_err(xdev->dev, "Invalid channel compatible node\n");
2832 		return -EINVAL;
2833 	}
2834 
2835 	/* Request the interrupt */
2836 	chan->irq = irq_of_parse_and_map(node, chan->tdest);
2837 	err = request_irq(chan->irq, xdev->dma_config->irq_handler,
2838 			  IRQF_SHARED, "xilinx-dma-controller", chan);
2839 	if (err) {
2840 		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
2841 		return err;
2842 	}
2843 
2844 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
2845 		chan->start_transfer = xilinx_dma_start_transfer;
2846 		chan->stop_transfer = xilinx_dma_stop_transfer;
2847 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
2848 		chan->start_transfer = xilinx_mcdma_start_transfer;
2849 		chan->stop_transfer = xilinx_dma_stop_transfer;
2850 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
2851 		chan->start_transfer = xilinx_cdma_start_transfer;
2852 		chan->stop_transfer = xilinx_cdma_stop_transfer;
2853 	} else {
2854 		chan->start_transfer = xilinx_vdma_start_transfer;
2855 		chan->stop_transfer = xilinx_dma_stop_transfer;
2856 	}
2857 
2858 	/* check if SG is enabled (only for AXIDMA, AXIMCDMA, and CDMA) */
2859 	if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) {
2860 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA ||
2861 		    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_setup(&chan->tasklet, xilinx_dma_do_tasklet);
2870 
2871 	/*
2872 	 * Initialize the DMA channel and add it to the DMA engine channels
2873 	 * list.
2874 	 */
2875 	chan->common.device = &xdev->common;
2876 
2877 	list_add_tail(&chan->common.device_node, &xdev->common.channels);
2878 	xdev->chan[chan->id] = chan;
2879 
2880 	/* Reset the channel */
2881 	err = xilinx_dma_chan_reset(chan);
2882 	if (err < 0) {
2883 		dev_err(xdev->dev, "Reset channel failed\n");
2884 		return err;
2885 	}
2886 
2887 	return 0;
2888 }
2889 
2890 /**
2891  * xilinx_dma_child_probe - Per child node probe
2892  * It get number of dma-channels per child node from
2893  * device-tree and initializes all the channels.
2894  *
2895  * @xdev: Driver specific device structure
2896  * @node: Device node
2897  *
2898  * Return: 0 always.
2899  */
2900 static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
2901 				    struct device_node *node)
2902 {
2903 	int ret, i;
2904 	u32 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 	err = dma_async_device_register(&xdev->common);
3117 	if (err) {
3118 		dev_err(xdev->dev, "failed to register the dma device\n");
3119 		goto error;
3120 	}
3121 
3122 	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
3123 					 xdev);
3124 	if (err < 0) {
3125 		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
3126 		dma_async_device_unregister(&xdev->common);
3127 		goto error;
3128 	}
3129 
3130 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
3131 		dev_info(&pdev->dev, "Xilinx AXI DMA Engine Driver Probed!!\n");
3132 	else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA)
3133 		dev_info(&pdev->dev, "Xilinx AXI CDMA Engine Driver Probed!!\n");
3134 	else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
3135 		dev_info(&pdev->dev, "Xilinx AXI MCDMA Engine Driver Probed!!\n");
3136 	else
3137 		dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
3138 
3139 	return 0;
3140 
3141 disable_clks:
3142 	xdma_disable_allclks(xdev);
3143 error:
3144 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3145 		if (xdev->chan[i])
3146 			xilinx_dma_chan_remove(xdev->chan[i]);
3147 
3148 	return err;
3149 }
3150 
3151 /**
3152  * xilinx_dma_remove - Driver remove function
3153  * @pdev: Pointer to the platform_device structure
3154  *
3155  * Return: Always '0'
3156  */
3157 static int xilinx_dma_remove(struct platform_device *pdev)
3158 {
3159 	struct xilinx_dma_device *xdev = platform_get_drvdata(pdev);
3160 	int i;
3161 
3162 	of_dma_controller_free(pdev->dev.of_node);
3163 
3164 	dma_async_device_unregister(&xdev->common);
3165 
3166 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3167 		if (xdev->chan[i])
3168 			xilinx_dma_chan_remove(xdev->chan[i]);
3169 
3170 	xdma_disable_allclks(xdev);
3171 
3172 	return 0;
3173 }
3174 
3175 static struct platform_driver xilinx_vdma_driver = {
3176 	.driver = {
3177 		.name = "xilinx-vdma",
3178 		.of_match_table = xilinx_dma_of_ids,
3179 	},
3180 	.probe = xilinx_dma_probe,
3181 	.remove = xilinx_dma_remove,
3182 };
3183 
3184 module_platform_driver(xilinx_vdma_driver);
3185 
3186 MODULE_AUTHOR("Xilinx, Inc.");
3187 MODULE_DESCRIPTION("Xilinx VDMA driver");
3188 MODULE_LICENSE("GPL v2");
3189