xref: /openbmc/linux/drivers/dma/xilinx/xilinx_dma.c (revision 3f58ff6b)
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  * @terminating: Check for channel being synchronized by user
398  * @tasklet: Cleanup work after irq
399  * @config: Device configuration info
400  * @flush_on_fsync: Flush on Frame sync
401  * @desc_pendingcount: Descriptor pending count
402  * @ext_addr: Indicates 64 bit addressing is supported by dma channel
403  * @desc_submitcount: Descriptor h/w submitted count
404  * @seg_v: Statically allocated segments base
405  * @seg_mv: Statically allocated segments base for MCDMA
406  * @seg_p: Physical allocated segments base
407  * @cyclic_seg_v: Statically allocated segment base for cyclic transfers
408  * @cyclic_seg_p: Physical allocated segments base for cyclic dma
409  * @start_transfer: Differentiate b/w DMA IP's transfer
410  * @stop_transfer: Differentiate b/w DMA IP's quiesce
411  * @tdest: TDEST value for mcdma
412  * @has_vflip: S2MM vertical flip
413  */
414 struct xilinx_dma_chan {
415 	struct xilinx_dma_device *xdev;
416 	u32 ctrl_offset;
417 	u32 desc_offset;
418 	spinlock_t lock;
419 	struct list_head pending_list;
420 	struct list_head active_list;
421 	struct list_head done_list;
422 	struct list_head free_seg_list;
423 	struct dma_chan common;
424 	struct dma_pool *desc_pool;
425 	struct device *dev;
426 	int irq;
427 	int id;
428 	enum dma_transfer_direction direction;
429 	int num_frms;
430 	bool has_sg;
431 	bool cyclic;
432 	bool genlock;
433 	bool err;
434 	bool idle;
435 	bool terminating;
436 	struct tasklet_struct tasklet;
437 	struct xilinx_vdma_config config;
438 	bool flush_on_fsync;
439 	u32 desc_pendingcount;
440 	bool ext_addr;
441 	u32 desc_submitcount;
442 	struct xilinx_axidma_tx_segment *seg_v;
443 	struct xilinx_aximcdma_tx_segment *seg_mv;
444 	dma_addr_t seg_p;
445 	struct xilinx_axidma_tx_segment *cyclic_seg_v;
446 	dma_addr_t cyclic_seg_p;
447 	void (*start_transfer)(struct xilinx_dma_chan *chan);
448 	int (*stop_transfer)(struct xilinx_dma_chan *chan);
449 	u16 tdest;
450 	bool has_vflip;
451 };
452 
453 /**
454  * enum xdma_ip_type - DMA IP type.
455  *
456  * @XDMA_TYPE_AXIDMA: Axi dma ip.
457  * @XDMA_TYPE_CDMA: Axi cdma ip.
458  * @XDMA_TYPE_VDMA: Axi vdma ip.
459  * @XDMA_TYPE_AXIMCDMA: Axi MCDMA ip.
460  *
461  */
462 enum xdma_ip_type {
463 	XDMA_TYPE_AXIDMA = 0,
464 	XDMA_TYPE_CDMA,
465 	XDMA_TYPE_VDMA,
466 	XDMA_TYPE_AXIMCDMA
467 };
468 
469 struct xilinx_dma_config {
470 	enum xdma_ip_type dmatype;
471 	int (*clk_init)(struct platform_device *pdev, struct clk **axi_clk,
472 			struct clk **tx_clk, struct clk **txs_clk,
473 			struct clk **rx_clk, struct clk **rxs_clk);
474 	irqreturn_t (*irq_handler)(int irq, void *data);
475 	const int max_channels;
476 };
477 
478 /**
479  * struct xilinx_dma_device - DMA device structure
480  * @regs: I/O mapped base address
481  * @dev: Device Structure
482  * @common: DMA device structure
483  * @chan: Driver specific DMA channel
484  * @flush_on_fsync: Flush on frame sync
485  * @ext_addr: Indicates 64 bit addressing is supported by dma device
486  * @pdev: Platform device structure pointer
487  * @dma_config: DMA config structure
488  * @axi_clk: DMA Axi4-lite interace clock
489  * @tx_clk: DMA mm2s clock
490  * @txs_clk: DMA mm2s stream clock
491  * @rx_clk: DMA s2mm clock
492  * @rxs_clk: DMA s2mm stream clock
493  * @s2mm_chan_id: DMA s2mm channel identifier
494  * @mm2s_chan_id: DMA mm2s channel identifier
495  * @max_buffer_len: Max buffer length
496  */
497 struct xilinx_dma_device {
498 	void __iomem *regs;
499 	struct device *dev;
500 	struct dma_device common;
501 	struct xilinx_dma_chan *chan[XILINX_MCDMA_MAX_CHANS_PER_DEVICE];
502 	u32 flush_on_fsync;
503 	bool ext_addr;
504 	struct platform_device  *pdev;
505 	const struct xilinx_dma_config *dma_config;
506 	struct clk *axi_clk;
507 	struct clk *tx_clk;
508 	struct clk *txs_clk;
509 	struct clk *rx_clk;
510 	struct clk *rxs_clk;
511 	u32 s2mm_chan_id;
512 	u32 mm2s_chan_id;
513 	u32 max_buffer_len;
514 };
515 
516 /* Macros */
517 #define to_xilinx_chan(chan) \
518 	container_of(chan, struct xilinx_dma_chan, common)
519 #define to_dma_tx_descriptor(tx) \
520 	container_of(tx, struct xilinx_dma_tx_descriptor, async_tx)
521 #define xilinx_dma_poll_timeout(chan, reg, val, cond, delay_us, timeout_us) \
522 	readl_poll_timeout_atomic(chan->xdev->regs + chan->ctrl_offset + reg, \
523 				  val, cond, delay_us, timeout_us)
524 
525 /* IO accessors */
526 static inline u32 dma_read(struct xilinx_dma_chan *chan, u32 reg)
527 {
528 	return ioread32(chan->xdev->regs + reg);
529 }
530 
531 static inline void dma_write(struct xilinx_dma_chan *chan, u32 reg, u32 value)
532 {
533 	iowrite32(value, chan->xdev->regs + reg);
534 }
535 
536 static inline void vdma_desc_write(struct xilinx_dma_chan *chan, u32 reg,
537 				   u32 value)
538 {
539 	dma_write(chan, chan->desc_offset + reg, value);
540 }
541 
542 static inline u32 dma_ctrl_read(struct xilinx_dma_chan *chan, u32 reg)
543 {
544 	return dma_read(chan, chan->ctrl_offset + reg);
545 }
546 
547 static inline void dma_ctrl_write(struct xilinx_dma_chan *chan, u32 reg,
548 				   u32 value)
549 {
550 	dma_write(chan, chan->ctrl_offset + reg, value);
551 }
552 
553 static inline void dma_ctrl_clr(struct xilinx_dma_chan *chan, u32 reg,
554 				 u32 clr)
555 {
556 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) & ~clr);
557 }
558 
559 static inline void dma_ctrl_set(struct xilinx_dma_chan *chan, u32 reg,
560 				 u32 set)
561 {
562 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) | set);
563 }
564 
565 /**
566  * vdma_desc_write_64 - 64-bit descriptor write
567  * @chan: Driver specific VDMA channel
568  * @reg: Register to write
569  * @value_lsb: lower address of the descriptor.
570  * @value_msb: upper address of the descriptor.
571  *
572  * Since vdma driver is trying to write to a register offset which is not a
573  * multiple of 64 bits(ex : 0x5c), we are writing as two separate 32 bits
574  * instead of a single 64 bit register write.
575  */
576 static inline void vdma_desc_write_64(struct xilinx_dma_chan *chan, u32 reg,
577 				      u32 value_lsb, u32 value_msb)
578 {
579 	/* Write the lsb 32 bits*/
580 	writel(value_lsb, chan->xdev->regs + chan->desc_offset + reg);
581 
582 	/* Write the msb 32 bits */
583 	writel(value_msb, chan->xdev->regs + chan->desc_offset + reg + 4);
584 }
585 
586 static inline void dma_writeq(struct xilinx_dma_chan *chan, u32 reg, u64 value)
587 {
588 	lo_hi_writeq(value, chan->xdev->regs + chan->ctrl_offset + reg);
589 }
590 
591 static inline void xilinx_write(struct xilinx_dma_chan *chan, u32 reg,
592 				dma_addr_t addr)
593 {
594 	if (chan->ext_addr)
595 		dma_writeq(chan, reg, addr);
596 	else
597 		dma_ctrl_write(chan, reg, addr);
598 }
599 
600 static inline void xilinx_axidma_buf(struct xilinx_dma_chan *chan,
601 				     struct xilinx_axidma_desc_hw *hw,
602 				     dma_addr_t buf_addr, size_t sg_used,
603 				     size_t period_len)
604 {
605 	if (chan->ext_addr) {
606 		hw->buf_addr = lower_32_bits(buf_addr + sg_used + period_len);
607 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used +
608 						 period_len);
609 	} else {
610 		hw->buf_addr = buf_addr + sg_used + period_len;
611 	}
612 }
613 
614 static inline void xilinx_aximcdma_buf(struct xilinx_dma_chan *chan,
615 				       struct xilinx_aximcdma_desc_hw *hw,
616 				       dma_addr_t buf_addr, size_t sg_used)
617 {
618 	if (chan->ext_addr) {
619 		hw->buf_addr = lower_32_bits(buf_addr + sg_used);
620 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used);
621 	} else {
622 		hw->buf_addr = buf_addr + sg_used;
623 	}
624 }
625 
626 /* -----------------------------------------------------------------------------
627  * Descriptors and segments alloc and free
628  */
629 
630 /**
631  * xilinx_vdma_alloc_tx_segment - Allocate transaction segment
632  * @chan: Driver specific DMA channel
633  *
634  * Return: The allocated segment on success and NULL on failure.
635  */
636 static struct xilinx_vdma_tx_segment *
637 xilinx_vdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
638 {
639 	struct xilinx_vdma_tx_segment *segment;
640 	dma_addr_t phys;
641 
642 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
643 	if (!segment)
644 		return NULL;
645 
646 	segment->phys = phys;
647 
648 	return segment;
649 }
650 
651 /**
652  * xilinx_cdma_alloc_tx_segment - Allocate transaction segment
653  * @chan: Driver specific DMA channel
654  *
655  * Return: The allocated segment on success and NULL on failure.
656  */
657 static struct xilinx_cdma_tx_segment *
658 xilinx_cdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
659 {
660 	struct xilinx_cdma_tx_segment *segment;
661 	dma_addr_t phys;
662 
663 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
664 	if (!segment)
665 		return NULL;
666 
667 	segment->phys = phys;
668 
669 	return segment;
670 }
671 
672 /**
673  * xilinx_axidma_alloc_tx_segment - Allocate transaction segment
674  * @chan: Driver specific DMA channel
675  *
676  * Return: The allocated segment on success and NULL on failure.
677  */
678 static struct xilinx_axidma_tx_segment *
679 xilinx_axidma_alloc_tx_segment(struct xilinx_dma_chan *chan)
680 {
681 	struct xilinx_axidma_tx_segment *segment = NULL;
682 	unsigned long flags;
683 
684 	spin_lock_irqsave(&chan->lock, flags);
685 	if (!list_empty(&chan->free_seg_list)) {
686 		segment = list_first_entry(&chan->free_seg_list,
687 					   struct xilinx_axidma_tx_segment,
688 					   node);
689 		list_del(&segment->node);
690 	}
691 	spin_unlock_irqrestore(&chan->lock, flags);
692 
693 	if (!segment)
694 		dev_dbg(chan->dev, "Could not find free tx segment\n");
695 
696 	return segment;
697 }
698 
699 /**
700  * xilinx_aximcdma_alloc_tx_segment - Allocate transaction segment
701  * @chan: Driver specific DMA channel
702  *
703  * Return: The allocated segment on success and NULL on failure.
704  */
705 static struct xilinx_aximcdma_tx_segment *
706 xilinx_aximcdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
707 {
708 	struct xilinx_aximcdma_tx_segment *segment = NULL;
709 	unsigned long flags;
710 
711 	spin_lock_irqsave(&chan->lock, flags);
712 	if (!list_empty(&chan->free_seg_list)) {
713 		segment = list_first_entry(&chan->free_seg_list,
714 					   struct xilinx_aximcdma_tx_segment,
715 					   node);
716 		list_del(&segment->node);
717 	}
718 	spin_unlock_irqrestore(&chan->lock, flags);
719 
720 	return segment;
721 }
722 
723 static void xilinx_dma_clean_hw_desc(struct xilinx_axidma_desc_hw *hw)
724 {
725 	u32 next_desc = hw->next_desc;
726 	u32 next_desc_msb = hw->next_desc_msb;
727 
728 	memset(hw, 0, sizeof(struct xilinx_axidma_desc_hw));
729 
730 	hw->next_desc = next_desc;
731 	hw->next_desc_msb = next_desc_msb;
732 }
733 
734 static void xilinx_mcdma_clean_hw_desc(struct xilinx_aximcdma_desc_hw *hw)
735 {
736 	u32 next_desc = hw->next_desc;
737 	u32 next_desc_msb = hw->next_desc_msb;
738 
739 	memset(hw, 0, sizeof(struct xilinx_aximcdma_desc_hw));
740 
741 	hw->next_desc = next_desc;
742 	hw->next_desc_msb = next_desc_msb;
743 }
744 
745 /**
746  * xilinx_dma_free_tx_segment - Free transaction segment
747  * @chan: Driver specific DMA channel
748  * @segment: DMA transaction segment
749  */
750 static void xilinx_dma_free_tx_segment(struct xilinx_dma_chan *chan,
751 				struct xilinx_axidma_tx_segment *segment)
752 {
753 	xilinx_dma_clean_hw_desc(&segment->hw);
754 
755 	list_add_tail(&segment->node, &chan->free_seg_list);
756 }
757 
758 /**
759  * xilinx_mcdma_free_tx_segment - Free transaction segment
760  * @chan: Driver specific DMA channel
761  * @segment: DMA transaction segment
762  */
763 static void xilinx_mcdma_free_tx_segment(struct xilinx_dma_chan *chan,
764 					 struct xilinx_aximcdma_tx_segment *
765 					 segment)
766 {
767 	xilinx_mcdma_clean_hw_desc(&segment->hw);
768 
769 	list_add_tail(&segment->node, &chan->free_seg_list);
770 }
771 
772 /**
773  * xilinx_cdma_free_tx_segment - Free transaction segment
774  * @chan: Driver specific DMA channel
775  * @segment: DMA transaction segment
776  */
777 static void xilinx_cdma_free_tx_segment(struct xilinx_dma_chan *chan,
778 				struct xilinx_cdma_tx_segment *segment)
779 {
780 	dma_pool_free(chan->desc_pool, segment, segment->phys);
781 }
782 
783 /**
784  * xilinx_vdma_free_tx_segment - Free transaction segment
785  * @chan: Driver specific DMA channel
786  * @segment: DMA transaction segment
787  */
788 static void xilinx_vdma_free_tx_segment(struct xilinx_dma_chan *chan,
789 					struct xilinx_vdma_tx_segment *segment)
790 {
791 	dma_pool_free(chan->desc_pool, segment, segment->phys);
792 }
793 
794 /**
795  * xilinx_dma_alloc_tx_descriptor - Allocate transaction descriptor
796  * @chan: Driver specific DMA channel
797  *
798  * Return: The allocated descriptor on success and NULL on failure.
799  */
800 static struct xilinx_dma_tx_descriptor *
801 xilinx_dma_alloc_tx_descriptor(struct xilinx_dma_chan *chan)
802 {
803 	struct xilinx_dma_tx_descriptor *desc;
804 
805 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
806 	if (!desc)
807 		return NULL;
808 
809 	INIT_LIST_HEAD(&desc->segments);
810 
811 	return desc;
812 }
813 
814 /**
815  * xilinx_dma_free_tx_descriptor - Free transaction descriptor
816  * @chan: Driver specific DMA channel
817  * @desc: DMA transaction descriptor
818  */
819 static void
820 xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
821 			       struct xilinx_dma_tx_descriptor *desc)
822 {
823 	struct xilinx_vdma_tx_segment *segment, *next;
824 	struct xilinx_cdma_tx_segment *cdma_segment, *cdma_next;
825 	struct xilinx_axidma_tx_segment *axidma_segment, *axidma_next;
826 	struct xilinx_aximcdma_tx_segment *aximcdma_segment, *aximcdma_next;
827 
828 	if (!desc)
829 		return;
830 
831 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
832 		list_for_each_entry_safe(segment, next, &desc->segments, node) {
833 			list_del(&segment->node);
834 			xilinx_vdma_free_tx_segment(chan, segment);
835 		}
836 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
837 		list_for_each_entry_safe(cdma_segment, cdma_next,
838 					 &desc->segments, node) {
839 			list_del(&cdma_segment->node);
840 			xilinx_cdma_free_tx_segment(chan, cdma_segment);
841 		}
842 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
843 		list_for_each_entry_safe(axidma_segment, axidma_next,
844 					 &desc->segments, node) {
845 			list_del(&axidma_segment->node);
846 			xilinx_dma_free_tx_segment(chan, axidma_segment);
847 		}
848 	} else {
849 		list_for_each_entry_safe(aximcdma_segment, aximcdma_next,
850 					 &desc->segments, node) {
851 			list_del(&aximcdma_segment->node);
852 			xilinx_mcdma_free_tx_segment(chan, aximcdma_segment);
853 		}
854 	}
855 
856 	kfree(desc);
857 }
858 
859 /* Required functions */
860 
861 /**
862  * xilinx_dma_free_desc_list - Free descriptors list
863  * @chan: Driver specific DMA channel
864  * @list: List to parse and delete the descriptor
865  */
866 static void xilinx_dma_free_desc_list(struct xilinx_dma_chan *chan,
867 					struct list_head *list)
868 {
869 	struct xilinx_dma_tx_descriptor *desc, *next;
870 
871 	list_for_each_entry_safe(desc, next, list, node) {
872 		list_del(&desc->node);
873 		xilinx_dma_free_tx_descriptor(chan, desc);
874 	}
875 }
876 
877 /**
878  * xilinx_dma_free_descriptors - Free channel descriptors
879  * @chan: Driver specific DMA channel
880  */
881 static void xilinx_dma_free_descriptors(struct xilinx_dma_chan *chan)
882 {
883 	unsigned long flags;
884 
885 	spin_lock_irqsave(&chan->lock, flags);
886 
887 	xilinx_dma_free_desc_list(chan, &chan->pending_list);
888 	xilinx_dma_free_desc_list(chan, &chan->done_list);
889 	xilinx_dma_free_desc_list(chan, &chan->active_list);
890 
891 	spin_unlock_irqrestore(&chan->lock, flags);
892 }
893 
894 /**
895  * xilinx_dma_free_chan_resources - Free channel resources
896  * @dchan: DMA channel
897  */
898 static void xilinx_dma_free_chan_resources(struct dma_chan *dchan)
899 {
900 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
901 	unsigned long flags;
902 
903 	dev_dbg(chan->dev, "Free all channel resources.\n");
904 
905 	xilinx_dma_free_descriptors(chan);
906 
907 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
908 		spin_lock_irqsave(&chan->lock, flags);
909 		INIT_LIST_HEAD(&chan->free_seg_list);
910 		spin_unlock_irqrestore(&chan->lock, flags);
911 
912 		/* Free memory that is allocated for BD */
913 		dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
914 				  XILINX_DMA_NUM_DESCS, chan->seg_v,
915 				  chan->seg_p);
916 
917 		/* Free Memory that is allocated for cyclic DMA Mode */
918 		dma_free_coherent(chan->dev, sizeof(*chan->cyclic_seg_v),
919 				  chan->cyclic_seg_v, chan->cyclic_seg_p);
920 	}
921 
922 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
923 		spin_lock_irqsave(&chan->lock, flags);
924 		INIT_LIST_HEAD(&chan->free_seg_list);
925 		spin_unlock_irqrestore(&chan->lock, flags);
926 
927 		/* Free memory that is allocated for BD */
928 		dma_free_coherent(chan->dev, sizeof(*chan->seg_mv) *
929 				  XILINX_DMA_NUM_DESCS, chan->seg_mv,
930 				  chan->seg_p);
931 	}
932 
933 	if (chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA &&
934 	    chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA) {
935 		dma_pool_destroy(chan->desc_pool);
936 		chan->desc_pool = NULL;
937 	}
938 
939 }
940 
941 /**
942  * xilinx_dma_get_residue - Compute residue for a given descriptor
943  * @chan: Driver specific dma channel
944  * @desc: dma transaction descriptor
945  *
946  * Return: The number of residue bytes for the descriptor.
947  */
948 static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
949 				  struct xilinx_dma_tx_descriptor *desc)
950 {
951 	struct xilinx_cdma_tx_segment *cdma_seg;
952 	struct xilinx_axidma_tx_segment *axidma_seg;
953 	struct xilinx_aximcdma_tx_segment *aximcdma_seg;
954 	struct xilinx_cdma_desc_hw *cdma_hw;
955 	struct xilinx_axidma_desc_hw *axidma_hw;
956 	struct xilinx_aximcdma_desc_hw *aximcdma_hw;
957 	struct list_head *entry;
958 	u32 residue = 0;
959 
960 	list_for_each(entry, &desc->segments) {
961 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
962 			cdma_seg = list_entry(entry,
963 					      struct xilinx_cdma_tx_segment,
964 					      node);
965 			cdma_hw = &cdma_seg->hw;
966 			residue += (cdma_hw->control - cdma_hw->status) &
967 				   chan->xdev->max_buffer_len;
968 		} else if (chan->xdev->dma_config->dmatype ==
969 			   XDMA_TYPE_AXIDMA) {
970 			axidma_seg = list_entry(entry,
971 						struct xilinx_axidma_tx_segment,
972 						node);
973 			axidma_hw = &axidma_seg->hw;
974 			residue += (axidma_hw->control - axidma_hw->status) &
975 				   chan->xdev->max_buffer_len;
976 		} else {
977 			aximcdma_seg =
978 				list_entry(entry,
979 					   struct xilinx_aximcdma_tx_segment,
980 					   node);
981 			aximcdma_hw = &aximcdma_seg->hw;
982 			residue +=
983 				(aximcdma_hw->control - aximcdma_hw->status) &
984 				chan->xdev->max_buffer_len;
985 		}
986 	}
987 
988 	return residue;
989 }
990 
991 /**
992  * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
993  * @chan: Driver specific dma channel
994  * @desc: dma transaction descriptor
995  * @flags: flags for spin lock
996  */
997 static void xilinx_dma_chan_handle_cyclic(struct xilinx_dma_chan *chan,
998 					  struct xilinx_dma_tx_descriptor *desc,
999 					  unsigned long *flags)
1000 {
1001 	struct dmaengine_desc_callback cb;
1002 
1003 	dmaengine_desc_get_callback(&desc->async_tx, &cb);
1004 	if (dmaengine_desc_callback_valid(&cb)) {
1005 		spin_unlock_irqrestore(&chan->lock, *flags);
1006 		dmaengine_desc_callback_invoke(&cb, NULL);
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 		 * While we ran a callback the user called a terminate function,
1055 		 * which takes care of cleaning up any remaining descriptors
1056 		 */
1057 		if (chan->terminating)
1058 			break;
1059 	}
1060 
1061 	spin_unlock_irqrestore(&chan->lock, flags);
1062 }
1063 
1064 /**
1065  * xilinx_dma_do_tasklet - Schedule completion tasklet
1066  * @t: Pointer to the Xilinx DMA channel structure
1067  */
1068 static void xilinx_dma_do_tasklet(struct tasklet_struct *t)
1069 {
1070 	struct xilinx_dma_chan *chan = from_tasklet(chan, t, tasklet);
1071 
1072 	xilinx_dma_chan_desc_cleanup(chan);
1073 }
1074 
1075 /**
1076  * xilinx_dma_alloc_chan_resources - Allocate channel resources
1077  * @dchan: DMA channel
1078  *
1079  * Return: '0' on success and failure value on error
1080  */
1081 static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
1082 {
1083 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1084 	int i;
1085 
1086 	/* Has this channel already been allocated? */
1087 	if (chan->desc_pool)
1088 		return 0;
1089 
1090 	/*
1091 	 * We need the descriptor to be aligned to 64bytes
1092 	 * for meeting Xilinx VDMA specification requirement.
1093 	 */
1094 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1095 		/* Allocate the buffer descriptors. */
1096 		chan->seg_v = dma_alloc_coherent(chan->dev,
1097 						 sizeof(*chan->seg_v) * XILINX_DMA_NUM_DESCS,
1098 						 &chan->seg_p, GFP_KERNEL);
1099 		if (!chan->seg_v) {
1100 			dev_err(chan->dev,
1101 				"unable to allocate channel %d descriptors\n",
1102 				chan->id);
1103 			return -ENOMEM;
1104 		}
1105 		/*
1106 		 * For cyclic DMA mode we need to program the tail Descriptor
1107 		 * register with a value which is not a part of the BD chain
1108 		 * so allocating a desc segment during channel allocation for
1109 		 * programming tail descriptor.
1110 		 */
1111 		chan->cyclic_seg_v = dma_alloc_coherent(chan->dev,
1112 							sizeof(*chan->cyclic_seg_v),
1113 							&chan->cyclic_seg_p,
1114 							GFP_KERNEL);
1115 		if (!chan->cyclic_seg_v) {
1116 			dev_err(chan->dev,
1117 				"unable to allocate desc segment for cyclic DMA\n");
1118 			dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
1119 				XILINX_DMA_NUM_DESCS, chan->seg_v,
1120 				chan->seg_p);
1121 			return -ENOMEM;
1122 		}
1123 		chan->cyclic_seg_v->phys = chan->cyclic_seg_p;
1124 
1125 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1126 			chan->seg_v[i].hw.next_desc =
1127 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1128 				((i + 1) % XILINX_DMA_NUM_DESCS));
1129 			chan->seg_v[i].hw.next_desc_msb =
1130 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1131 				((i + 1) % XILINX_DMA_NUM_DESCS));
1132 			chan->seg_v[i].phys = chan->seg_p +
1133 				sizeof(*chan->seg_v) * i;
1134 			list_add_tail(&chan->seg_v[i].node,
1135 				      &chan->free_seg_list);
1136 		}
1137 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
1138 		/* Allocate the buffer descriptors. */
1139 		chan->seg_mv = dma_alloc_coherent(chan->dev,
1140 						  sizeof(*chan->seg_mv) *
1141 						  XILINX_DMA_NUM_DESCS,
1142 						  &chan->seg_p, GFP_KERNEL);
1143 		if (!chan->seg_mv) {
1144 			dev_err(chan->dev,
1145 				"unable to allocate channel %d descriptors\n",
1146 				chan->id);
1147 			return -ENOMEM;
1148 		}
1149 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1150 			chan->seg_mv[i].hw.next_desc =
1151 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1152 				((i + 1) % XILINX_DMA_NUM_DESCS));
1153 			chan->seg_mv[i].hw.next_desc_msb =
1154 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1155 				((i + 1) % XILINX_DMA_NUM_DESCS));
1156 			chan->seg_mv[i].phys = chan->seg_p +
1157 				sizeof(*chan->seg_mv) * i;
1158 			list_add_tail(&chan->seg_mv[i].node,
1159 				      &chan->free_seg_list);
1160 		}
1161 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1162 		chan->desc_pool = dma_pool_create("xilinx_cdma_desc_pool",
1163 				   chan->dev,
1164 				   sizeof(struct xilinx_cdma_tx_segment),
1165 				   __alignof__(struct xilinx_cdma_tx_segment),
1166 				   0);
1167 	} else {
1168 		chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
1169 				     chan->dev,
1170 				     sizeof(struct xilinx_vdma_tx_segment),
1171 				     __alignof__(struct xilinx_vdma_tx_segment),
1172 				     0);
1173 	}
1174 
1175 	if (!chan->desc_pool &&
1176 	    ((chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA) &&
1177 		chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA)) {
1178 		dev_err(chan->dev,
1179 			"unable to allocate channel %d descriptor pool\n",
1180 			chan->id);
1181 		return -ENOMEM;
1182 	}
1183 
1184 	dma_cookie_init(dchan);
1185 
1186 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1187 		/* For AXI DMA resetting once channel will reset the
1188 		 * other channel as well so enable the interrupts here.
1189 		 */
1190 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1191 			      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1192 	}
1193 
1194 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
1195 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1196 			     XILINX_CDMA_CR_SGMODE);
1197 
1198 	return 0;
1199 }
1200 
1201 /**
1202  * xilinx_dma_calc_copysize - Calculate the amount of data to copy
1203  * @chan: Driver specific DMA channel
1204  * @size: Total data that needs to be copied
1205  * @done: Amount of data that has been already copied
1206  *
1207  * Return: Amount of data that has to be copied
1208  */
1209 static int xilinx_dma_calc_copysize(struct xilinx_dma_chan *chan,
1210 				    int size, int done)
1211 {
1212 	size_t copy;
1213 
1214 	copy = min_t(size_t, size - done,
1215 		     chan->xdev->max_buffer_len);
1216 
1217 	if ((copy + done < size) &&
1218 	    chan->xdev->common.copy_align) {
1219 		/*
1220 		 * If this is not the last descriptor, make sure
1221 		 * the next one will be properly aligned
1222 		 */
1223 		copy = rounddown(copy,
1224 				 (1 << chan->xdev->common.copy_align));
1225 	}
1226 	return copy;
1227 }
1228 
1229 /**
1230  * xilinx_dma_tx_status - Get DMA transaction status
1231  * @dchan: DMA channel
1232  * @cookie: Transaction identifier
1233  * @txstate: Transaction state
1234  *
1235  * Return: DMA transaction status
1236  */
1237 static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
1238 					dma_cookie_t cookie,
1239 					struct dma_tx_state *txstate)
1240 {
1241 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1242 	struct xilinx_dma_tx_descriptor *desc;
1243 	enum dma_status ret;
1244 	unsigned long flags;
1245 	u32 residue = 0;
1246 
1247 	ret = dma_cookie_status(dchan, cookie, txstate);
1248 	if (ret == DMA_COMPLETE || !txstate)
1249 		return ret;
1250 
1251 	spin_lock_irqsave(&chan->lock, flags);
1252 	if (!list_empty(&chan->active_list)) {
1253 		desc = list_last_entry(&chan->active_list,
1254 				       struct xilinx_dma_tx_descriptor, node);
1255 		/*
1256 		 * VDMA and simple mode do not support residue reporting, so the
1257 		 * residue field will always be 0.
1258 		 */
1259 		if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA)
1260 			residue = xilinx_dma_get_residue(chan, desc);
1261 	}
1262 	spin_unlock_irqrestore(&chan->lock, flags);
1263 
1264 	dma_set_residue(txstate, residue);
1265 
1266 	return ret;
1267 }
1268 
1269 /**
1270  * xilinx_dma_stop_transfer - Halt DMA channel
1271  * @chan: Driver specific DMA channel
1272  *
1273  * Return: '0' on success and failure value on error
1274  */
1275 static int xilinx_dma_stop_transfer(struct xilinx_dma_chan *chan)
1276 {
1277 	u32 val;
1278 
1279 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1280 
1281 	/* Wait for the hardware to halt */
1282 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1283 				       val & XILINX_DMA_DMASR_HALTED, 0,
1284 				       XILINX_DMA_LOOP_COUNT);
1285 }
1286 
1287 /**
1288  * xilinx_cdma_stop_transfer - Wait for the current transfer to complete
1289  * @chan: Driver specific DMA channel
1290  *
1291  * Return: '0' on success and failure value on error
1292  */
1293 static int xilinx_cdma_stop_transfer(struct xilinx_dma_chan *chan)
1294 {
1295 	u32 val;
1296 
1297 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1298 				       val & XILINX_DMA_DMASR_IDLE, 0,
1299 				       XILINX_DMA_LOOP_COUNT);
1300 }
1301 
1302 /**
1303  * xilinx_dma_start - Start DMA channel
1304  * @chan: Driver specific DMA channel
1305  */
1306 static void xilinx_dma_start(struct xilinx_dma_chan *chan)
1307 {
1308 	int err;
1309 	u32 val;
1310 
1311 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1312 
1313 	/* Wait for the hardware to start */
1314 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1315 				      !(val & XILINX_DMA_DMASR_HALTED), 0,
1316 				      XILINX_DMA_LOOP_COUNT);
1317 
1318 	if (err) {
1319 		dev_err(chan->dev, "Cannot start channel %p: %x\n",
1320 			chan, dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1321 
1322 		chan->err = true;
1323 	}
1324 }
1325 
1326 /**
1327  * xilinx_vdma_start_transfer - Starts VDMA transfer
1328  * @chan: Driver specific channel struct pointer
1329  */
1330 static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
1331 {
1332 	struct xilinx_vdma_config *config = &chan->config;
1333 	struct xilinx_dma_tx_descriptor *desc;
1334 	u32 reg, j;
1335 	struct xilinx_vdma_tx_segment *segment, *last = NULL;
1336 	int i = 0;
1337 
1338 	/* This function was invoked with lock held */
1339 	if (chan->err)
1340 		return;
1341 
1342 	if (!chan->idle)
1343 		return;
1344 
1345 	if (list_empty(&chan->pending_list))
1346 		return;
1347 
1348 	desc = list_first_entry(&chan->pending_list,
1349 				struct xilinx_dma_tx_descriptor, node);
1350 
1351 	/* Configure the hardware using info in the config structure */
1352 	if (chan->has_vflip) {
1353 		reg = dma_read(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP);
1354 		reg &= ~XILINX_VDMA_ENABLE_VERTICAL_FLIP;
1355 		reg |= config->vflip_en;
1356 		dma_write(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP,
1357 			  reg);
1358 	}
1359 
1360 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1361 
1362 	if (config->frm_cnt_en)
1363 		reg |= XILINX_DMA_DMACR_FRAMECNT_EN;
1364 	else
1365 		reg &= ~XILINX_DMA_DMACR_FRAMECNT_EN;
1366 
1367 	/* If not parking, enable circular mode */
1368 	if (config->park)
1369 		reg &= ~XILINX_DMA_DMACR_CIRC_EN;
1370 	else
1371 		reg |= XILINX_DMA_DMACR_CIRC_EN;
1372 
1373 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1374 
1375 	j = chan->desc_submitcount;
1376 	reg = dma_read(chan, XILINX_DMA_REG_PARK_PTR);
1377 	if (chan->direction == DMA_MEM_TO_DEV) {
1378 		reg &= ~XILINX_DMA_PARK_PTR_RD_REF_MASK;
1379 		reg |= j << XILINX_DMA_PARK_PTR_RD_REF_SHIFT;
1380 	} else {
1381 		reg &= ~XILINX_DMA_PARK_PTR_WR_REF_MASK;
1382 		reg |= j << XILINX_DMA_PARK_PTR_WR_REF_SHIFT;
1383 	}
1384 	dma_write(chan, XILINX_DMA_REG_PARK_PTR, reg);
1385 
1386 	/* Start the hardware */
1387 	xilinx_dma_start(chan);
1388 
1389 	if (chan->err)
1390 		return;
1391 
1392 	/* Start the transfer */
1393 	if (chan->desc_submitcount < chan->num_frms)
1394 		i = chan->desc_submitcount;
1395 
1396 	list_for_each_entry(segment, &desc->segments, node) {
1397 		if (chan->ext_addr)
1398 			vdma_desc_write_64(chan,
1399 				   XILINX_VDMA_REG_START_ADDRESS_64(i++),
1400 				   segment->hw.buf_addr,
1401 				   segment->hw.buf_addr_msb);
1402 		else
1403 			vdma_desc_write(chan,
1404 					XILINX_VDMA_REG_START_ADDRESS(i++),
1405 					segment->hw.buf_addr);
1406 
1407 		last = segment;
1408 	}
1409 
1410 	if (!last)
1411 		return;
1412 
1413 	/* HW expects these parameters to be same for one transaction */
1414 	vdma_desc_write(chan, XILINX_DMA_REG_HSIZE, last->hw.hsize);
1415 	vdma_desc_write(chan, XILINX_DMA_REG_FRMDLY_STRIDE,
1416 			last->hw.stride);
1417 	vdma_desc_write(chan, XILINX_DMA_REG_VSIZE, last->hw.vsize);
1418 
1419 	chan->desc_submitcount++;
1420 	chan->desc_pendingcount--;
1421 	list_move_tail(&desc->node, &chan->active_list);
1422 	if (chan->desc_submitcount == chan->num_frms)
1423 		chan->desc_submitcount = 0;
1424 
1425 	chan->idle = false;
1426 }
1427 
1428 /**
1429  * xilinx_cdma_start_transfer - Starts cdma transfer
1430  * @chan: Driver specific channel struct pointer
1431  */
1432 static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
1433 {
1434 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1435 	struct xilinx_cdma_tx_segment *tail_segment;
1436 	u32 ctrl_reg = dma_read(chan, XILINX_DMA_REG_DMACR);
1437 
1438 	if (chan->err)
1439 		return;
1440 
1441 	if (!chan->idle)
1442 		return;
1443 
1444 	if (list_empty(&chan->pending_list))
1445 		return;
1446 
1447 	head_desc = list_first_entry(&chan->pending_list,
1448 				     struct xilinx_dma_tx_descriptor, node);
1449 	tail_desc = list_last_entry(&chan->pending_list,
1450 				    struct xilinx_dma_tx_descriptor, node);
1451 	tail_segment = list_last_entry(&tail_desc->segments,
1452 				       struct xilinx_cdma_tx_segment, node);
1453 
1454 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1455 		ctrl_reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1456 		ctrl_reg |= chan->desc_pendingcount <<
1457 				XILINX_DMA_CR_COALESCE_SHIFT;
1458 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, ctrl_reg);
1459 	}
1460 
1461 	if (chan->has_sg) {
1462 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
1463 			     XILINX_CDMA_CR_SGMODE);
1464 
1465 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1466 			     XILINX_CDMA_CR_SGMODE);
1467 
1468 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1469 			     head_desc->async_tx.phys);
1470 
1471 		/* Update tail ptr register which will start the transfer */
1472 		xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1473 			     tail_segment->phys);
1474 	} else {
1475 		/* In simple mode */
1476 		struct xilinx_cdma_tx_segment *segment;
1477 		struct xilinx_cdma_desc_hw *hw;
1478 
1479 		segment = list_first_entry(&head_desc->segments,
1480 					   struct xilinx_cdma_tx_segment,
1481 					   node);
1482 
1483 		hw = &segment->hw;
1484 
1485 		xilinx_write(chan, XILINX_CDMA_REG_SRCADDR,
1486 			     xilinx_prep_dma_addr_t(hw->src_addr));
1487 		xilinx_write(chan, XILINX_CDMA_REG_DSTADDR,
1488 			     xilinx_prep_dma_addr_t(hw->dest_addr));
1489 
1490 		/* Start the transfer */
1491 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1492 				hw->control & chan->xdev->max_buffer_len);
1493 	}
1494 
1495 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1496 	chan->desc_pendingcount = 0;
1497 	chan->idle = false;
1498 }
1499 
1500 /**
1501  * xilinx_dma_start_transfer - Starts DMA transfer
1502  * @chan: Driver specific channel struct pointer
1503  */
1504 static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
1505 {
1506 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1507 	struct xilinx_axidma_tx_segment *tail_segment;
1508 	u32 reg;
1509 
1510 	if (chan->err)
1511 		return;
1512 
1513 	if (list_empty(&chan->pending_list))
1514 		return;
1515 
1516 	if (!chan->idle)
1517 		return;
1518 
1519 	head_desc = list_first_entry(&chan->pending_list,
1520 				     struct xilinx_dma_tx_descriptor, node);
1521 	tail_desc = list_last_entry(&chan->pending_list,
1522 				    struct xilinx_dma_tx_descriptor, node);
1523 	tail_segment = list_last_entry(&tail_desc->segments,
1524 				       struct xilinx_axidma_tx_segment, node);
1525 
1526 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1527 
1528 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1529 		reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1530 		reg |= chan->desc_pendingcount <<
1531 				  XILINX_DMA_CR_COALESCE_SHIFT;
1532 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1533 	}
1534 
1535 	if (chan->has_sg)
1536 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1537 			     head_desc->async_tx.phys);
1538 
1539 	xilinx_dma_start(chan);
1540 
1541 	if (chan->err)
1542 		return;
1543 
1544 	/* Start the transfer */
1545 	if (chan->has_sg) {
1546 		if (chan->cyclic)
1547 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1548 				     chan->cyclic_seg_v->phys);
1549 		else
1550 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1551 				     tail_segment->phys);
1552 	} else {
1553 		struct xilinx_axidma_tx_segment *segment;
1554 		struct xilinx_axidma_desc_hw *hw;
1555 
1556 		segment = list_first_entry(&head_desc->segments,
1557 					   struct xilinx_axidma_tx_segment,
1558 					   node);
1559 		hw = &segment->hw;
1560 
1561 		xilinx_write(chan, XILINX_DMA_REG_SRCDSTADDR,
1562 			     xilinx_prep_dma_addr_t(hw->buf_addr));
1563 
1564 		/* Start the transfer */
1565 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1566 			       hw->control & chan->xdev->max_buffer_len);
1567 	}
1568 
1569 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1570 	chan->desc_pendingcount = 0;
1571 	chan->idle = false;
1572 }
1573 
1574 /**
1575  * xilinx_mcdma_start_transfer - Starts MCDMA transfer
1576  * @chan: Driver specific channel struct pointer
1577  */
1578 static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan)
1579 {
1580 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1581 	struct xilinx_aximcdma_tx_segment *tail_segment;
1582 	u32 reg;
1583 
1584 	/*
1585 	 * lock has been held by calling functions, so we don't need it
1586 	 * to take it here again.
1587 	 */
1588 
1589 	if (chan->err)
1590 		return;
1591 
1592 	if (!chan->idle)
1593 		return;
1594 
1595 	if (list_empty(&chan->pending_list))
1596 		return;
1597 
1598 	head_desc = list_first_entry(&chan->pending_list,
1599 				     struct xilinx_dma_tx_descriptor, node);
1600 	tail_desc = list_last_entry(&chan->pending_list,
1601 				    struct xilinx_dma_tx_descriptor, node);
1602 	tail_segment = list_last_entry(&tail_desc->segments,
1603 				       struct xilinx_aximcdma_tx_segment, node);
1604 
1605 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1606 
1607 	if (chan->desc_pendingcount <= XILINX_MCDMA_COALESCE_MAX) {
1608 		reg &= ~XILINX_MCDMA_COALESCE_MASK;
1609 		reg |= chan->desc_pendingcount <<
1610 			XILINX_MCDMA_COALESCE_SHIFT;
1611 	}
1612 
1613 	reg |= XILINX_MCDMA_IRQ_ALL_MASK;
1614 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1615 
1616 	/* Program current descriptor */
1617 	xilinx_write(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET(chan->tdest),
1618 		     head_desc->async_tx.phys);
1619 
1620 	/* Program channel enable register */
1621 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHEN_OFFSET);
1622 	reg |= BIT(chan->tdest);
1623 	dma_ctrl_write(chan, XILINX_MCDMA_CHEN_OFFSET, reg);
1624 
1625 	/* Start the fetch of BDs for the channel */
1626 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1627 	reg |= XILINX_MCDMA_CR_RUNSTOP_MASK;
1628 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1629 
1630 	xilinx_dma_start(chan);
1631 
1632 	if (chan->err)
1633 		return;
1634 
1635 	/* Start the transfer */
1636 	xilinx_write(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET(chan->tdest),
1637 		     tail_segment->phys);
1638 
1639 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1640 	chan->desc_pendingcount = 0;
1641 	chan->idle = false;
1642 }
1643 
1644 /**
1645  * xilinx_dma_issue_pending - Issue pending transactions
1646  * @dchan: DMA channel
1647  */
1648 static void xilinx_dma_issue_pending(struct dma_chan *dchan)
1649 {
1650 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1651 	unsigned long flags;
1652 
1653 	spin_lock_irqsave(&chan->lock, flags);
1654 	chan->start_transfer(chan);
1655 	spin_unlock_irqrestore(&chan->lock, flags);
1656 }
1657 
1658 /**
1659  * xilinx_dma_device_config - Configure the DMA channel
1660  * @dchan: DMA channel
1661  * @config: channel configuration
1662  *
1663  * Return: 0 always.
1664  */
1665 static int xilinx_dma_device_config(struct dma_chan *dchan,
1666 				    struct dma_slave_config *config)
1667 {
1668 	return 0;
1669 }
1670 
1671 /**
1672  * xilinx_dma_complete_descriptor - Mark the active descriptor as complete
1673  * @chan : xilinx DMA channel
1674  *
1675  * CONTEXT: hardirq
1676  */
1677 static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
1678 {
1679 	struct xilinx_dma_tx_descriptor *desc, *next;
1680 
1681 	/* This function was invoked with lock held */
1682 	if (list_empty(&chan->active_list))
1683 		return;
1684 
1685 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
1686 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
1687 		    XDMA_TYPE_VDMA)
1688 			desc->residue = xilinx_dma_get_residue(chan, desc);
1689 		else
1690 			desc->residue = 0;
1691 		desc->err = chan->err;
1692 
1693 		list_del(&desc->node);
1694 		if (!desc->cyclic)
1695 			dma_cookie_complete(&desc->async_tx);
1696 		list_add_tail(&desc->node, &chan->done_list);
1697 	}
1698 }
1699 
1700 /**
1701  * xilinx_dma_reset - Reset DMA channel
1702  * @chan: Driver specific DMA channel
1703  *
1704  * Return: '0' on success and failure value on error
1705  */
1706 static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
1707 {
1708 	int err;
1709 	u32 tmp;
1710 
1711 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RESET);
1712 
1713 	/* Wait for the hardware to finish reset */
1714 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMACR, tmp,
1715 				      !(tmp & XILINX_DMA_DMACR_RESET), 0,
1716 				      XILINX_DMA_LOOP_COUNT);
1717 
1718 	if (err) {
1719 		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
1720 			dma_ctrl_read(chan, XILINX_DMA_REG_DMACR),
1721 			dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1722 		return -ETIMEDOUT;
1723 	}
1724 
1725 	chan->err = false;
1726 	chan->idle = true;
1727 	chan->desc_pendingcount = 0;
1728 	chan->desc_submitcount = 0;
1729 
1730 	return err;
1731 }
1732 
1733 /**
1734  * xilinx_dma_chan_reset - Reset DMA channel and enable interrupts
1735  * @chan: Driver specific DMA channel
1736  *
1737  * Return: '0' on success and failure value on error
1738  */
1739 static int xilinx_dma_chan_reset(struct xilinx_dma_chan *chan)
1740 {
1741 	int err;
1742 
1743 	/* Reset VDMA */
1744 	err = xilinx_dma_reset(chan);
1745 	if (err)
1746 		return err;
1747 
1748 	/* Enable interrupts */
1749 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1750 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1751 
1752 	return 0;
1753 }
1754 
1755 /**
1756  * xilinx_mcdma_irq_handler - MCDMA Interrupt handler
1757  * @irq: IRQ number
1758  * @data: Pointer to the Xilinx MCDMA channel structure
1759  *
1760  * Return: IRQ_HANDLED/IRQ_NONE
1761  */
1762 static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
1763 {
1764 	struct xilinx_dma_chan *chan = data;
1765 	u32 status, ser_offset, chan_sermask, chan_offset = 0, chan_id;
1766 
1767 	if (chan->direction == DMA_DEV_TO_MEM)
1768 		ser_offset = XILINX_MCDMA_RXINT_SER_OFFSET;
1769 	else
1770 		ser_offset = XILINX_MCDMA_TXINT_SER_OFFSET;
1771 
1772 	/* Read the channel id raising the interrupt*/
1773 	chan_sermask = dma_ctrl_read(chan, ser_offset);
1774 	chan_id = ffs(chan_sermask);
1775 
1776 	if (!chan_id)
1777 		return IRQ_NONE;
1778 
1779 	if (chan->direction == DMA_DEV_TO_MEM)
1780 		chan_offset = chan->xdev->dma_config->max_channels / 2;
1781 
1782 	chan_offset = chan_offset + (chan_id - 1);
1783 	chan = chan->xdev->chan[chan_offset];
1784 	/* Read the status and ack the interrupts. */
1785 	status = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest));
1786 	if (!(status & XILINX_MCDMA_IRQ_ALL_MASK))
1787 		return IRQ_NONE;
1788 
1789 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest),
1790 		       status & XILINX_MCDMA_IRQ_ALL_MASK);
1791 
1792 	if (status & XILINX_MCDMA_IRQ_ERR_MASK) {
1793 		dev_err(chan->dev, "Channel %p has errors %x cdr %x tdr %x\n",
1794 			chan,
1795 			dma_ctrl_read(chan, XILINX_MCDMA_CH_ERR_OFFSET),
1796 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET
1797 				      (chan->tdest)),
1798 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET
1799 				      (chan->tdest)));
1800 		chan->err = true;
1801 	}
1802 
1803 	if (status & XILINX_MCDMA_IRQ_DELAY_MASK) {
1804 		/*
1805 		 * Device takes too long to do the transfer when user requires
1806 		 * responsiveness.
1807 		 */
1808 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1809 	}
1810 
1811 	if (status & XILINX_MCDMA_IRQ_IOC_MASK) {
1812 		spin_lock(&chan->lock);
1813 		xilinx_dma_complete_descriptor(chan);
1814 		chan->idle = true;
1815 		chan->start_transfer(chan);
1816 		spin_unlock(&chan->lock);
1817 	}
1818 
1819 	tasklet_schedule(&chan->tasklet);
1820 	return IRQ_HANDLED;
1821 }
1822 
1823 /**
1824  * xilinx_dma_irq_handler - DMA Interrupt handler
1825  * @irq: IRQ number
1826  * @data: Pointer to the Xilinx DMA channel structure
1827  *
1828  * Return: IRQ_HANDLED/IRQ_NONE
1829  */
1830 static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
1831 {
1832 	struct xilinx_dma_chan *chan = data;
1833 	u32 status;
1834 
1835 	/* Read the status and ack the interrupts. */
1836 	status = dma_ctrl_read(chan, XILINX_DMA_REG_DMASR);
1837 	if (!(status & XILINX_DMA_DMAXR_ALL_IRQ_MASK))
1838 		return IRQ_NONE;
1839 
1840 	dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1841 			status & XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1842 
1843 	if (status & XILINX_DMA_DMASR_ERR_IRQ) {
1844 		/*
1845 		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
1846 		 * error is recoverable, ignore it. Otherwise flag the error.
1847 		 *
1848 		 * Only recoverable errors can be cleared in the DMASR register,
1849 		 * make sure not to write to other error bits to 1.
1850 		 */
1851 		u32 errors = status & XILINX_DMA_DMASR_ALL_ERR_MASK;
1852 
1853 		dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1854 				errors & XILINX_DMA_DMASR_ERR_RECOVER_MASK);
1855 
1856 		if (!chan->flush_on_fsync ||
1857 		    (errors & ~XILINX_DMA_DMASR_ERR_RECOVER_MASK)) {
1858 			dev_err(chan->dev,
1859 				"Channel %p has errors %x, cdr %x tdr %x\n",
1860 				chan, errors,
1861 				dma_ctrl_read(chan, XILINX_DMA_REG_CURDESC),
1862 				dma_ctrl_read(chan, XILINX_DMA_REG_TAILDESC));
1863 			chan->err = true;
1864 		}
1865 	}
1866 
1867 	if (status & XILINX_DMA_DMASR_DLY_CNT_IRQ) {
1868 		/*
1869 		 * Device takes too long to do the transfer when user requires
1870 		 * responsiveness.
1871 		 */
1872 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1873 	}
1874 
1875 	if (status & XILINX_DMA_DMASR_FRM_CNT_IRQ) {
1876 		spin_lock(&chan->lock);
1877 		xilinx_dma_complete_descriptor(chan);
1878 		chan->idle = true;
1879 		chan->start_transfer(chan);
1880 		spin_unlock(&chan->lock);
1881 	}
1882 
1883 	tasklet_schedule(&chan->tasklet);
1884 	return IRQ_HANDLED;
1885 }
1886 
1887 /**
1888  * append_desc_queue - Queuing descriptor
1889  * @chan: Driver specific dma channel
1890  * @desc: dma transaction descriptor
1891  */
1892 static void append_desc_queue(struct xilinx_dma_chan *chan,
1893 			      struct xilinx_dma_tx_descriptor *desc)
1894 {
1895 	struct xilinx_vdma_tx_segment *tail_segment;
1896 	struct xilinx_dma_tx_descriptor *tail_desc;
1897 	struct xilinx_axidma_tx_segment *axidma_tail_segment;
1898 	struct xilinx_aximcdma_tx_segment *aximcdma_tail_segment;
1899 	struct xilinx_cdma_tx_segment *cdma_tail_segment;
1900 
1901 	if (list_empty(&chan->pending_list))
1902 		goto append;
1903 
1904 	/*
1905 	 * Add the hardware descriptor to the chain of hardware descriptors
1906 	 * that already exists in memory.
1907 	 */
1908 	tail_desc = list_last_entry(&chan->pending_list,
1909 				    struct xilinx_dma_tx_descriptor, node);
1910 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
1911 		tail_segment = list_last_entry(&tail_desc->segments,
1912 					       struct xilinx_vdma_tx_segment,
1913 					       node);
1914 		tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1915 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1916 		cdma_tail_segment = list_last_entry(&tail_desc->segments,
1917 						struct xilinx_cdma_tx_segment,
1918 						node);
1919 		cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1920 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1921 		axidma_tail_segment = list_last_entry(&tail_desc->segments,
1922 					       struct xilinx_axidma_tx_segment,
1923 					       node);
1924 		axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1925 	} else {
1926 		aximcdma_tail_segment =
1927 			list_last_entry(&tail_desc->segments,
1928 					struct xilinx_aximcdma_tx_segment,
1929 					node);
1930 		aximcdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1931 	}
1932 
1933 	/*
1934 	 * Add the software descriptor and all children to the list
1935 	 * of pending transactions
1936 	 */
1937 append:
1938 	list_add_tail(&desc->node, &chan->pending_list);
1939 	chan->desc_pendingcount++;
1940 
1941 	if (chan->has_sg && (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA)
1942 	    && unlikely(chan->desc_pendingcount > chan->num_frms)) {
1943 		dev_dbg(chan->dev, "desc pendingcount is too high\n");
1944 		chan->desc_pendingcount = chan->num_frms;
1945 	}
1946 }
1947 
1948 /**
1949  * xilinx_dma_tx_submit - Submit DMA transaction
1950  * @tx: Async transaction descriptor
1951  *
1952  * Return: cookie value on success and failure value on error
1953  */
1954 static dma_cookie_t xilinx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
1955 {
1956 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
1957 	struct xilinx_dma_chan *chan = to_xilinx_chan(tx->chan);
1958 	dma_cookie_t cookie;
1959 	unsigned long flags;
1960 	int err;
1961 
1962 	if (chan->cyclic) {
1963 		xilinx_dma_free_tx_descriptor(chan, desc);
1964 		return -EBUSY;
1965 	}
1966 
1967 	if (chan->err) {
1968 		/*
1969 		 * If reset fails, need to hard reset the system.
1970 		 * Channel is no longer functional
1971 		 */
1972 		err = xilinx_dma_chan_reset(chan);
1973 		if (err < 0)
1974 			return err;
1975 	}
1976 
1977 	spin_lock_irqsave(&chan->lock, flags);
1978 
1979 	cookie = dma_cookie_assign(tx);
1980 
1981 	/* Put this transaction onto the tail of the pending queue */
1982 	append_desc_queue(chan, desc);
1983 
1984 	if (desc->cyclic)
1985 		chan->cyclic = true;
1986 
1987 	chan->terminating = false;
1988 
1989 	spin_unlock_irqrestore(&chan->lock, flags);
1990 
1991 	return cookie;
1992 }
1993 
1994 /**
1995  * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
1996  *	DMA_SLAVE transaction
1997  * @dchan: DMA channel
1998  * @xt: Interleaved template pointer
1999  * @flags: transfer ack flags
2000  *
2001  * Return: Async transaction descriptor on success and NULL on failure
2002  */
2003 static struct dma_async_tx_descriptor *
2004 xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
2005 				 struct dma_interleaved_template *xt,
2006 				 unsigned long flags)
2007 {
2008 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2009 	struct xilinx_dma_tx_descriptor *desc;
2010 	struct xilinx_vdma_tx_segment *segment;
2011 	struct xilinx_vdma_desc_hw *hw;
2012 
2013 	if (!is_slave_direction(xt->dir))
2014 		return NULL;
2015 
2016 	if (!xt->numf || !xt->sgl[0].size)
2017 		return NULL;
2018 
2019 	if (xt->frame_size != 1)
2020 		return NULL;
2021 
2022 	/* Allocate a transaction descriptor. */
2023 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2024 	if (!desc)
2025 		return NULL;
2026 
2027 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2028 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2029 	async_tx_ack(&desc->async_tx);
2030 
2031 	/* Allocate the link descriptor from DMA pool */
2032 	segment = xilinx_vdma_alloc_tx_segment(chan);
2033 	if (!segment)
2034 		goto error;
2035 
2036 	/* Fill in the hardware descriptor */
2037 	hw = &segment->hw;
2038 	hw->vsize = xt->numf;
2039 	hw->hsize = xt->sgl[0].size;
2040 	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
2041 			XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT;
2042 	hw->stride |= chan->config.frm_dly <<
2043 			XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
2044 
2045 	if (xt->dir != DMA_MEM_TO_DEV) {
2046 		if (chan->ext_addr) {
2047 			hw->buf_addr = lower_32_bits(xt->dst_start);
2048 			hw->buf_addr_msb = upper_32_bits(xt->dst_start);
2049 		} else {
2050 			hw->buf_addr = xt->dst_start;
2051 		}
2052 	} else {
2053 		if (chan->ext_addr) {
2054 			hw->buf_addr = lower_32_bits(xt->src_start);
2055 			hw->buf_addr_msb = upper_32_bits(xt->src_start);
2056 		} else {
2057 			hw->buf_addr = xt->src_start;
2058 		}
2059 	}
2060 
2061 	/* Insert the segment into the descriptor segments list. */
2062 	list_add_tail(&segment->node, &desc->segments);
2063 
2064 	/* Link the last hardware descriptor with the first. */
2065 	segment = list_first_entry(&desc->segments,
2066 				   struct xilinx_vdma_tx_segment, node);
2067 	desc->async_tx.phys = segment->phys;
2068 
2069 	return &desc->async_tx;
2070 
2071 error:
2072 	xilinx_dma_free_tx_descriptor(chan, desc);
2073 	return NULL;
2074 }
2075 
2076 /**
2077  * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
2078  * @dchan: DMA channel
2079  * @dma_dst: destination address
2080  * @dma_src: source address
2081  * @len: transfer length
2082  * @flags: transfer ack flags
2083  *
2084  * Return: Async transaction descriptor on success and NULL on failure
2085  */
2086 static struct dma_async_tx_descriptor *
2087 xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
2088 			dma_addr_t dma_src, size_t len, unsigned long flags)
2089 {
2090 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2091 	struct xilinx_dma_tx_descriptor *desc;
2092 	struct xilinx_cdma_tx_segment *segment;
2093 	struct xilinx_cdma_desc_hw *hw;
2094 
2095 	if (!len || len > chan->xdev->max_buffer_len)
2096 		return NULL;
2097 
2098 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2099 	if (!desc)
2100 		return NULL;
2101 
2102 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2103 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2104 
2105 	/* Allocate the link descriptor from DMA pool */
2106 	segment = xilinx_cdma_alloc_tx_segment(chan);
2107 	if (!segment)
2108 		goto error;
2109 
2110 	hw = &segment->hw;
2111 	hw->control = len;
2112 	hw->src_addr = dma_src;
2113 	hw->dest_addr = dma_dst;
2114 	if (chan->ext_addr) {
2115 		hw->src_addr_msb = upper_32_bits(dma_src);
2116 		hw->dest_addr_msb = upper_32_bits(dma_dst);
2117 	}
2118 
2119 	/* Insert the segment into the descriptor segments list. */
2120 	list_add_tail(&segment->node, &desc->segments);
2121 
2122 	desc->async_tx.phys = segment->phys;
2123 	hw->next_desc = segment->phys;
2124 
2125 	return &desc->async_tx;
2126 
2127 error:
2128 	xilinx_dma_free_tx_descriptor(chan, desc);
2129 	return NULL;
2130 }
2131 
2132 /**
2133  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2134  * @dchan: DMA channel
2135  * @sgl: scatterlist to transfer to/from
2136  * @sg_len: number of entries in @scatterlist
2137  * @direction: DMA direction
2138  * @flags: transfer ack flags
2139  * @context: APP words of the descriptor
2140  *
2141  * Return: Async transaction descriptor on success and NULL on failure
2142  */
2143 static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
2144 	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
2145 	enum dma_transfer_direction direction, unsigned long flags,
2146 	void *context)
2147 {
2148 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2149 	struct xilinx_dma_tx_descriptor *desc;
2150 	struct xilinx_axidma_tx_segment *segment = NULL;
2151 	u32 *app_w = (u32 *)context;
2152 	struct scatterlist *sg;
2153 	size_t copy;
2154 	size_t sg_used;
2155 	unsigned int i;
2156 
2157 	if (!is_slave_direction(direction))
2158 		return NULL;
2159 
2160 	/* Allocate a transaction descriptor. */
2161 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2162 	if (!desc)
2163 		return NULL;
2164 
2165 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2166 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2167 
2168 	/* Build transactions using information in the scatter gather list */
2169 	for_each_sg(sgl, sg, sg_len, i) {
2170 		sg_used = 0;
2171 
2172 		/* Loop until the entire scatterlist entry is used */
2173 		while (sg_used < sg_dma_len(sg)) {
2174 			struct xilinx_axidma_desc_hw *hw;
2175 
2176 			/* Get a free segment */
2177 			segment = xilinx_axidma_alloc_tx_segment(chan);
2178 			if (!segment)
2179 				goto error;
2180 
2181 			/*
2182 			 * Calculate the maximum number of bytes to transfer,
2183 			 * making sure it is less than the hw limit
2184 			 */
2185 			copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
2186 							sg_used);
2187 			hw = &segment->hw;
2188 
2189 			/* Fill in the descriptor */
2190 			xilinx_axidma_buf(chan, hw, sg_dma_address(sg),
2191 					  sg_used, 0);
2192 
2193 			hw->control = copy;
2194 
2195 			if (chan->direction == DMA_MEM_TO_DEV) {
2196 				if (app_w)
2197 					memcpy(hw->app, app_w, sizeof(u32) *
2198 					       XILINX_DMA_NUM_APP_WORDS);
2199 			}
2200 
2201 			sg_used += copy;
2202 
2203 			/*
2204 			 * Insert the segment into the descriptor segments
2205 			 * list.
2206 			 */
2207 			list_add_tail(&segment->node, &desc->segments);
2208 		}
2209 	}
2210 
2211 	segment = list_first_entry(&desc->segments,
2212 				   struct xilinx_axidma_tx_segment, node);
2213 	desc->async_tx.phys = segment->phys;
2214 
2215 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2216 	if (chan->direction == DMA_MEM_TO_DEV) {
2217 		segment->hw.control |= XILINX_DMA_BD_SOP;
2218 		segment = list_last_entry(&desc->segments,
2219 					  struct xilinx_axidma_tx_segment,
2220 					  node);
2221 		segment->hw.control |= XILINX_DMA_BD_EOP;
2222 	}
2223 
2224 	return &desc->async_tx;
2225 
2226 error:
2227 	xilinx_dma_free_tx_descriptor(chan, desc);
2228 	return NULL;
2229 }
2230 
2231 /**
2232  * xilinx_dma_prep_dma_cyclic - prepare descriptors for a DMA_SLAVE transaction
2233  * @dchan: DMA channel
2234  * @buf_addr: Physical address of the buffer
2235  * @buf_len: Total length of the cyclic buffers
2236  * @period_len: length of individual cyclic buffer
2237  * @direction: DMA direction
2238  * @flags: transfer ack flags
2239  *
2240  * Return: Async transaction descriptor on success and NULL on failure
2241  */
2242 static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
2243 	struct dma_chan *dchan, dma_addr_t buf_addr, size_t buf_len,
2244 	size_t period_len, enum dma_transfer_direction direction,
2245 	unsigned long flags)
2246 {
2247 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2248 	struct xilinx_dma_tx_descriptor *desc;
2249 	struct xilinx_axidma_tx_segment *segment, *head_segment, *prev = NULL;
2250 	size_t copy, sg_used;
2251 	unsigned int num_periods;
2252 	int i;
2253 	u32 reg;
2254 
2255 	if (!period_len)
2256 		return NULL;
2257 
2258 	num_periods = buf_len / period_len;
2259 
2260 	if (!num_periods)
2261 		return NULL;
2262 
2263 	if (!is_slave_direction(direction))
2264 		return NULL;
2265 
2266 	/* Allocate a transaction descriptor. */
2267 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2268 	if (!desc)
2269 		return NULL;
2270 
2271 	chan->direction = direction;
2272 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2273 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2274 
2275 	for (i = 0; i < num_periods; ++i) {
2276 		sg_used = 0;
2277 
2278 		while (sg_used < period_len) {
2279 			struct xilinx_axidma_desc_hw *hw;
2280 
2281 			/* Get a free segment */
2282 			segment = xilinx_axidma_alloc_tx_segment(chan);
2283 			if (!segment)
2284 				goto error;
2285 
2286 			/*
2287 			 * Calculate the maximum number of bytes to transfer,
2288 			 * making sure it is less than the hw limit
2289 			 */
2290 			copy = xilinx_dma_calc_copysize(chan, period_len,
2291 							sg_used);
2292 			hw = &segment->hw;
2293 			xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
2294 					  period_len * i);
2295 			hw->control = copy;
2296 
2297 			if (prev)
2298 				prev->hw.next_desc = segment->phys;
2299 
2300 			prev = segment;
2301 			sg_used += copy;
2302 
2303 			/*
2304 			 * Insert the segment into the descriptor segments
2305 			 * list.
2306 			 */
2307 			list_add_tail(&segment->node, &desc->segments);
2308 		}
2309 	}
2310 
2311 	head_segment = list_first_entry(&desc->segments,
2312 				   struct xilinx_axidma_tx_segment, node);
2313 	desc->async_tx.phys = head_segment->phys;
2314 
2315 	desc->cyclic = true;
2316 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2317 	reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2318 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2319 
2320 	segment = list_last_entry(&desc->segments,
2321 				  struct xilinx_axidma_tx_segment,
2322 				  node);
2323 	segment->hw.next_desc = (u32) head_segment->phys;
2324 
2325 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2326 	if (direction == DMA_MEM_TO_DEV) {
2327 		head_segment->hw.control |= XILINX_DMA_BD_SOP;
2328 		segment->hw.control |= XILINX_DMA_BD_EOP;
2329 	}
2330 
2331 	return &desc->async_tx;
2332 
2333 error:
2334 	xilinx_dma_free_tx_descriptor(chan, desc);
2335 	return NULL;
2336 }
2337 
2338 /**
2339  * xilinx_mcdma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2340  * @dchan: DMA channel
2341  * @sgl: scatterlist to transfer to/from
2342  * @sg_len: number of entries in @scatterlist
2343  * @direction: DMA direction
2344  * @flags: transfer ack flags
2345  * @context: APP words of the descriptor
2346  *
2347  * Return: Async transaction descriptor on success and NULL on failure
2348  */
2349 static struct dma_async_tx_descriptor *
2350 xilinx_mcdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
2351 			   unsigned int sg_len,
2352 			   enum dma_transfer_direction direction,
2353 			   unsigned long flags, void *context)
2354 {
2355 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2356 	struct xilinx_dma_tx_descriptor *desc;
2357 	struct xilinx_aximcdma_tx_segment *segment = NULL;
2358 	u32 *app_w = (u32 *)context;
2359 	struct scatterlist *sg;
2360 	size_t copy;
2361 	size_t sg_used;
2362 	unsigned int i;
2363 
2364 	if (!is_slave_direction(direction))
2365 		return NULL;
2366 
2367 	/* Allocate a transaction descriptor. */
2368 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2369 	if (!desc)
2370 		return NULL;
2371 
2372 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2373 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2374 
2375 	/* Build transactions using information in the scatter gather list */
2376 	for_each_sg(sgl, sg, sg_len, i) {
2377 		sg_used = 0;
2378 
2379 		/* Loop until the entire scatterlist entry is used */
2380 		while (sg_used < sg_dma_len(sg)) {
2381 			struct xilinx_aximcdma_desc_hw *hw;
2382 
2383 			/* Get a free segment */
2384 			segment = xilinx_aximcdma_alloc_tx_segment(chan);
2385 			if (!segment)
2386 				goto error;
2387 
2388 			/*
2389 			 * Calculate the maximum number of bytes to transfer,
2390 			 * making sure it is less than the hw limit
2391 			 */
2392 			copy = min_t(size_t, sg_dma_len(sg) - sg_used,
2393 				     chan->xdev->max_buffer_len);
2394 			hw = &segment->hw;
2395 
2396 			/* Fill in the descriptor */
2397 			xilinx_aximcdma_buf(chan, hw, sg_dma_address(sg),
2398 					    sg_used);
2399 			hw->control = copy;
2400 
2401 			if (chan->direction == DMA_MEM_TO_DEV && app_w) {
2402 				memcpy(hw->app, app_w, sizeof(u32) *
2403 				       XILINX_DMA_NUM_APP_WORDS);
2404 			}
2405 
2406 			sg_used += copy;
2407 			/*
2408 			 * Insert the segment into the descriptor segments
2409 			 * list.
2410 			 */
2411 			list_add_tail(&segment->node, &desc->segments);
2412 		}
2413 	}
2414 
2415 	segment = list_first_entry(&desc->segments,
2416 				   struct xilinx_aximcdma_tx_segment, node);
2417 	desc->async_tx.phys = segment->phys;
2418 
2419 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2420 	if (chan->direction == DMA_MEM_TO_DEV) {
2421 		segment->hw.control |= XILINX_MCDMA_BD_SOP;
2422 		segment = list_last_entry(&desc->segments,
2423 					  struct xilinx_aximcdma_tx_segment,
2424 					  node);
2425 		segment->hw.control |= XILINX_MCDMA_BD_EOP;
2426 	}
2427 
2428 	return &desc->async_tx;
2429 
2430 error:
2431 	xilinx_dma_free_tx_descriptor(chan, desc);
2432 
2433 	return NULL;
2434 }
2435 
2436 /**
2437  * xilinx_dma_terminate_all - Halt the channel and free descriptors
2438  * @dchan: Driver specific DMA Channel pointer
2439  *
2440  * Return: '0' always.
2441  */
2442 static int xilinx_dma_terminate_all(struct dma_chan *dchan)
2443 {
2444 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2445 	u32 reg;
2446 	int err;
2447 
2448 	if (!chan->cyclic) {
2449 		err = chan->stop_transfer(chan);
2450 		if (err) {
2451 			dev_err(chan->dev, "Cannot stop channel %p: %x\n",
2452 				chan, dma_ctrl_read(chan,
2453 				XILINX_DMA_REG_DMASR));
2454 			chan->err = true;
2455 		}
2456 	}
2457 
2458 	xilinx_dma_chan_reset(chan);
2459 	/* Remove and free all of the descriptors in the lists */
2460 	chan->terminating = true;
2461 	xilinx_dma_free_descriptors(chan);
2462 	chan->idle = true;
2463 
2464 	if (chan->cyclic) {
2465 		reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2466 		reg &= ~XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2467 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2468 		chan->cyclic = false;
2469 	}
2470 
2471 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
2472 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2473 			     XILINX_CDMA_CR_SGMODE);
2474 
2475 	return 0;
2476 }
2477 
2478 static void xilinx_dma_synchronize(struct dma_chan *dchan)
2479 {
2480 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2481 
2482 	tasklet_kill(&chan->tasklet);
2483 }
2484 
2485 /**
2486  * xilinx_vdma_channel_set_config - Configure VDMA channel
2487  * Run-time configuration for Axi VDMA, supports:
2488  * . halt the channel
2489  * . configure interrupt coalescing and inter-packet delay threshold
2490  * . start/stop parking
2491  * . enable genlock
2492  *
2493  * @dchan: DMA channel
2494  * @cfg: VDMA device configuration pointer
2495  *
2496  * Return: '0' on success and failure value on error
2497  */
2498 int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
2499 					struct xilinx_vdma_config *cfg)
2500 {
2501 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2502 	u32 dmacr;
2503 
2504 	if (cfg->reset)
2505 		return xilinx_dma_chan_reset(chan);
2506 
2507 	dmacr = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2508 
2509 	chan->config.frm_dly = cfg->frm_dly;
2510 	chan->config.park = cfg->park;
2511 
2512 	/* genlock settings */
2513 	chan->config.gen_lock = cfg->gen_lock;
2514 	chan->config.master = cfg->master;
2515 
2516 	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
2517 	if (cfg->gen_lock && chan->genlock) {
2518 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
2519 		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
2520 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
2521 	}
2522 
2523 	chan->config.frm_cnt_en = cfg->frm_cnt_en;
2524 	chan->config.vflip_en = cfg->vflip_en;
2525 
2526 	if (cfg->park)
2527 		chan->config.park_frm = cfg->park_frm;
2528 	else
2529 		chan->config.park_frm = -1;
2530 
2531 	chan->config.coalesc = cfg->coalesc;
2532 	chan->config.delay = cfg->delay;
2533 
2534 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
2535 		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
2536 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
2537 		chan->config.coalesc = cfg->coalesc;
2538 	}
2539 
2540 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
2541 		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
2542 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
2543 		chan->config.delay = cfg->delay;
2544 	}
2545 
2546 	/* FSync Source selection */
2547 	dmacr &= ~XILINX_DMA_DMACR_FSYNCSRC_MASK;
2548 	dmacr |= cfg->ext_fsync << XILINX_DMA_DMACR_FSYNCSRC_SHIFT;
2549 
2550 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, dmacr);
2551 
2552 	return 0;
2553 }
2554 EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
2555 
2556 /* -----------------------------------------------------------------------------
2557  * Probe and remove
2558  */
2559 
2560 /**
2561  * xilinx_dma_chan_remove - Per Channel remove function
2562  * @chan: Driver specific DMA channel
2563  */
2564 static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
2565 {
2566 	/* Disable all interrupts */
2567 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2568 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
2569 
2570 	if (chan->irq > 0)
2571 		free_irq(chan->irq, chan);
2572 
2573 	tasklet_kill(&chan->tasklet);
2574 
2575 	list_del(&chan->common.device_node);
2576 }
2577 
2578 static int axidma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2579 			    struct clk **tx_clk, struct clk **rx_clk,
2580 			    struct clk **sg_clk, struct clk **tmp_clk)
2581 {
2582 	int err;
2583 
2584 	*tmp_clk = NULL;
2585 
2586 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2587 	if (IS_ERR(*axi_clk))
2588 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2589 
2590 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2591 	if (IS_ERR(*tx_clk))
2592 		*tx_clk = NULL;
2593 
2594 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2595 	if (IS_ERR(*rx_clk))
2596 		*rx_clk = NULL;
2597 
2598 	*sg_clk = devm_clk_get(&pdev->dev, "m_axi_sg_aclk");
2599 	if (IS_ERR(*sg_clk))
2600 		*sg_clk = NULL;
2601 
2602 	err = clk_prepare_enable(*axi_clk);
2603 	if (err) {
2604 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2605 		return err;
2606 	}
2607 
2608 	err = clk_prepare_enable(*tx_clk);
2609 	if (err) {
2610 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2611 		goto err_disable_axiclk;
2612 	}
2613 
2614 	err = clk_prepare_enable(*rx_clk);
2615 	if (err) {
2616 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2617 		goto err_disable_txclk;
2618 	}
2619 
2620 	err = clk_prepare_enable(*sg_clk);
2621 	if (err) {
2622 		dev_err(&pdev->dev, "failed to enable sg_clk (%d)\n", err);
2623 		goto err_disable_rxclk;
2624 	}
2625 
2626 	return 0;
2627 
2628 err_disable_rxclk:
2629 	clk_disable_unprepare(*rx_clk);
2630 err_disable_txclk:
2631 	clk_disable_unprepare(*tx_clk);
2632 err_disable_axiclk:
2633 	clk_disable_unprepare(*axi_clk);
2634 
2635 	return err;
2636 }
2637 
2638 static int axicdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2639 			    struct clk **dev_clk, struct clk **tmp_clk,
2640 			    struct clk **tmp1_clk, struct clk **tmp2_clk)
2641 {
2642 	int err;
2643 
2644 	*tmp_clk = NULL;
2645 	*tmp1_clk = NULL;
2646 	*tmp2_clk = NULL;
2647 
2648 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2649 	if (IS_ERR(*axi_clk))
2650 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2651 
2652 	*dev_clk = devm_clk_get(&pdev->dev, "m_axi_aclk");
2653 	if (IS_ERR(*dev_clk))
2654 		return dev_err_probe(&pdev->dev, PTR_ERR(*dev_clk), "failed to get dev_clk\n");
2655 
2656 	err = clk_prepare_enable(*axi_clk);
2657 	if (err) {
2658 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2659 		return err;
2660 	}
2661 
2662 	err = clk_prepare_enable(*dev_clk);
2663 	if (err) {
2664 		dev_err(&pdev->dev, "failed to enable dev_clk (%d)\n", err);
2665 		goto err_disable_axiclk;
2666 	}
2667 
2668 	return 0;
2669 
2670 err_disable_axiclk:
2671 	clk_disable_unprepare(*axi_clk);
2672 
2673 	return err;
2674 }
2675 
2676 static int axivdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2677 			    struct clk **tx_clk, struct clk **txs_clk,
2678 			    struct clk **rx_clk, struct clk **rxs_clk)
2679 {
2680 	int err;
2681 
2682 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2683 	if (IS_ERR(*axi_clk))
2684 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2685 
2686 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2687 	if (IS_ERR(*tx_clk))
2688 		*tx_clk = NULL;
2689 
2690 	*txs_clk = devm_clk_get(&pdev->dev, "m_axis_mm2s_aclk");
2691 	if (IS_ERR(*txs_clk))
2692 		*txs_clk = NULL;
2693 
2694 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2695 	if (IS_ERR(*rx_clk))
2696 		*rx_clk = NULL;
2697 
2698 	*rxs_clk = devm_clk_get(&pdev->dev, "s_axis_s2mm_aclk");
2699 	if (IS_ERR(*rxs_clk))
2700 		*rxs_clk = NULL;
2701 
2702 	err = clk_prepare_enable(*axi_clk);
2703 	if (err) {
2704 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n",
2705 			err);
2706 		return err;
2707 	}
2708 
2709 	err = clk_prepare_enable(*tx_clk);
2710 	if (err) {
2711 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2712 		goto err_disable_axiclk;
2713 	}
2714 
2715 	err = clk_prepare_enable(*txs_clk);
2716 	if (err) {
2717 		dev_err(&pdev->dev, "failed to enable txs_clk (%d)\n", err);
2718 		goto err_disable_txclk;
2719 	}
2720 
2721 	err = clk_prepare_enable(*rx_clk);
2722 	if (err) {
2723 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2724 		goto err_disable_txsclk;
2725 	}
2726 
2727 	err = clk_prepare_enable(*rxs_clk);
2728 	if (err) {
2729 		dev_err(&pdev->dev, "failed to enable rxs_clk (%d)\n", err);
2730 		goto err_disable_rxclk;
2731 	}
2732 
2733 	return 0;
2734 
2735 err_disable_rxclk:
2736 	clk_disable_unprepare(*rx_clk);
2737 err_disable_txsclk:
2738 	clk_disable_unprepare(*txs_clk);
2739 err_disable_txclk:
2740 	clk_disable_unprepare(*tx_clk);
2741 err_disable_axiclk:
2742 	clk_disable_unprepare(*axi_clk);
2743 
2744 	return err;
2745 }
2746 
2747 static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
2748 {
2749 	clk_disable_unprepare(xdev->rxs_clk);
2750 	clk_disable_unprepare(xdev->rx_clk);
2751 	clk_disable_unprepare(xdev->txs_clk);
2752 	clk_disable_unprepare(xdev->tx_clk);
2753 	clk_disable_unprepare(xdev->axi_clk);
2754 }
2755 
2756 /**
2757  * xilinx_dma_chan_probe - Per Channel Probing
2758  * It get channel features from the device tree entry and
2759  * initialize special channel handling routines
2760  *
2761  * @xdev: Driver specific device structure
2762  * @node: Device node
2763  *
2764  * Return: '0' on success and failure value on error
2765  */
2766 static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
2767 				  struct device_node *node)
2768 {
2769 	struct xilinx_dma_chan *chan;
2770 	bool has_dre = false;
2771 	u32 value, width;
2772 	int err;
2773 
2774 	/* Allocate and initialize the channel structure */
2775 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
2776 	if (!chan)
2777 		return -ENOMEM;
2778 
2779 	chan->dev = xdev->dev;
2780 	chan->xdev = xdev;
2781 	chan->desc_pendingcount = 0x0;
2782 	chan->ext_addr = xdev->ext_addr;
2783 	/* This variable ensures that descriptors are not
2784 	 * Submitted when dma engine is in progress. This variable is
2785 	 * Added to avoid polling for a bit in the status register to
2786 	 * Know dma state in the driver hot path.
2787 	 */
2788 	chan->idle = true;
2789 
2790 	spin_lock_init(&chan->lock);
2791 	INIT_LIST_HEAD(&chan->pending_list);
2792 	INIT_LIST_HEAD(&chan->done_list);
2793 	INIT_LIST_HEAD(&chan->active_list);
2794 	INIT_LIST_HEAD(&chan->free_seg_list);
2795 
2796 	/* Retrieve the channel properties from the device tree */
2797 	has_dre = of_property_read_bool(node, "xlnx,include-dre");
2798 
2799 	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
2800 
2801 	err = of_property_read_u32(node, "xlnx,datawidth", &value);
2802 	if (err) {
2803 		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
2804 		return err;
2805 	}
2806 	width = value >> 3; /* Convert bits to bytes */
2807 
2808 	/* If data width is greater than 8 bytes, DRE is not in hw */
2809 	if (width > 8)
2810 		has_dre = false;
2811 
2812 	if (!has_dre)
2813 		xdev->common.copy_align = (enum dmaengine_alignment)fls(width - 1);
2814 
2815 	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel") ||
2816 	    of_device_is_compatible(node, "xlnx,axi-dma-mm2s-channel") ||
2817 	    of_device_is_compatible(node, "xlnx,axi-cdma-channel")) {
2818 		chan->direction = DMA_MEM_TO_DEV;
2819 		chan->id = xdev->mm2s_chan_id++;
2820 		chan->tdest = chan->id;
2821 
2822 		chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
2823 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2824 			chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
2825 			chan->config.park = 1;
2826 
2827 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2828 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
2829 				chan->flush_on_fsync = true;
2830 		}
2831 	} else if (of_device_is_compatible(node,
2832 					   "xlnx,axi-vdma-s2mm-channel") ||
2833 		   of_device_is_compatible(node,
2834 					   "xlnx,axi-dma-s2mm-channel")) {
2835 		chan->direction = DMA_DEV_TO_MEM;
2836 		chan->id = xdev->s2mm_chan_id++;
2837 		chan->tdest = chan->id - xdev->dma_config->max_channels / 2;
2838 		chan->has_vflip = of_property_read_bool(node,
2839 					"xlnx,enable-vert-flip");
2840 		if (chan->has_vflip) {
2841 			chan->config.vflip_en = dma_read(chan,
2842 				XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP) &
2843 				XILINX_VDMA_ENABLE_VERTICAL_FLIP;
2844 		}
2845 
2846 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
2847 			chan->ctrl_offset = XILINX_MCDMA_S2MM_CTRL_OFFSET;
2848 		else
2849 			chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
2850 
2851 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2852 			chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
2853 			chan->config.park = 1;
2854 
2855 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2856 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
2857 				chan->flush_on_fsync = true;
2858 		}
2859 	} else {
2860 		dev_err(xdev->dev, "Invalid channel compatible node\n");
2861 		return -EINVAL;
2862 	}
2863 
2864 	/* Request the interrupt */
2865 	chan->irq = of_irq_get(node, chan->tdest);
2866 	if (chan->irq < 0)
2867 		return dev_err_probe(xdev->dev, chan->irq, "failed to get irq\n");
2868 	err = request_irq(chan->irq, xdev->dma_config->irq_handler,
2869 			  IRQF_SHARED, "xilinx-dma-controller", chan);
2870 	if (err) {
2871 		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
2872 		return err;
2873 	}
2874 
2875 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
2876 		chan->start_transfer = xilinx_dma_start_transfer;
2877 		chan->stop_transfer = xilinx_dma_stop_transfer;
2878 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
2879 		chan->start_transfer = xilinx_mcdma_start_transfer;
2880 		chan->stop_transfer = xilinx_dma_stop_transfer;
2881 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
2882 		chan->start_transfer = xilinx_cdma_start_transfer;
2883 		chan->stop_transfer = xilinx_cdma_stop_transfer;
2884 	} else {
2885 		chan->start_transfer = xilinx_vdma_start_transfer;
2886 		chan->stop_transfer = xilinx_dma_stop_transfer;
2887 	}
2888 
2889 	/* check if SG is enabled (only for AXIDMA, AXIMCDMA, and CDMA) */
2890 	if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) {
2891 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA ||
2892 		    dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) &
2893 			    XILINX_DMA_DMASR_SG_MASK)
2894 			chan->has_sg = true;
2895 		dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id,
2896 			chan->has_sg ? "enabled" : "disabled");
2897 	}
2898 
2899 	/* Initialize the tasklet */
2900 	tasklet_setup(&chan->tasklet, xilinx_dma_do_tasklet);
2901 
2902 	/*
2903 	 * Initialize the DMA channel and add it to the DMA engine channels
2904 	 * list.
2905 	 */
2906 	chan->common.device = &xdev->common;
2907 
2908 	list_add_tail(&chan->common.device_node, &xdev->common.channels);
2909 	xdev->chan[chan->id] = chan;
2910 
2911 	/* Reset the channel */
2912 	err = xilinx_dma_chan_reset(chan);
2913 	if (err < 0) {
2914 		dev_err(xdev->dev, "Reset channel failed\n");
2915 		return err;
2916 	}
2917 
2918 	return 0;
2919 }
2920 
2921 /**
2922  * xilinx_dma_child_probe - Per child node probe
2923  * It get number of dma-channels per child node from
2924  * device-tree and initializes all the channels.
2925  *
2926  * @xdev: Driver specific device structure
2927  * @node: Device node
2928  *
2929  * Return: '0' on success and failure value on error.
2930  */
2931 static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
2932 				    struct device_node *node)
2933 {
2934 	int ret, i;
2935 	u32 nr_channels = 1;
2936 
2937 	ret = of_property_read_u32(node, "dma-channels", &nr_channels);
2938 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA && ret < 0)
2939 		dev_warn(xdev->dev, "missing dma-channels property\n");
2940 
2941 	for (i = 0; i < nr_channels; i++) {
2942 		ret = xilinx_dma_chan_probe(xdev, node);
2943 		if (ret)
2944 			return ret;
2945 	}
2946 
2947 	return 0;
2948 }
2949 
2950 /**
2951  * of_dma_xilinx_xlate - Translation function
2952  * @dma_spec: Pointer to DMA specifier as found in the device tree
2953  * @ofdma: Pointer to DMA controller data
2954  *
2955  * Return: DMA channel pointer on success and NULL on error
2956  */
2957 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
2958 						struct of_dma *ofdma)
2959 {
2960 	struct xilinx_dma_device *xdev = ofdma->of_dma_data;
2961 	int chan_id = dma_spec->args[0];
2962 
2963 	if (chan_id >= xdev->dma_config->max_channels || !xdev->chan[chan_id])
2964 		return NULL;
2965 
2966 	return dma_get_slave_channel(&xdev->chan[chan_id]->common);
2967 }
2968 
2969 static const struct xilinx_dma_config axidma_config = {
2970 	.dmatype = XDMA_TYPE_AXIDMA,
2971 	.clk_init = axidma_clk_init,
2972 	.irq_handler = xilinx_dma_irq_handler,
2973 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
2974 };
2975 
2976 static const struct xilinx_dma_config aximcdma_config = {
2977 	.dmatype = XDMA_TYPE_AXIMCDMA,
2978 	.clk_init = axidma_clk_init,
2979 	.irq_handler = xilinx_mcdma_irq_handler,
2980 	.max_channels = XILINX_MCDMA_MAX_CHANS_PER_DEVICE,
2981 };
2982 static const struct xilinx_dma_config axicdma_config = {
2983 	.dmatype = XDMA_TYPE_CDMA,
2984 	.clk_init = axicdma_clk_init,
2985 	.irq_handler = xilinx_dma_irq_handler,
2986 	.max_channels = XILINX_CDMA_MAX_CHANS_PER_DEVICE,
2987 };
2988 
2989 static const struct xilinx_dma_config axivdma_config = {
2990 	.dmatype = XDMA_TYPE_VDMA,
2991 	.clk_init = axivdma_clk_init,
2992 	.irq_handler = xilinx_dma_irq_handler,
2993 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
2994 };
2995 
2996 static const struct of_device_id xilinx_dma_of_ids[] = {
2997 	{ .compatible = "xlnx,axi-dma-1.00.a", .data = &axidma_config },
2998 	{ .compatible = "xlnx,axi-cdma-1.00.a", .data = &axicdma_config },
2999 	{ .compatible = "xlnx,axi-vdma-1.00.a", .data = &axivdma_config },
3000 	{ .compatible = "xlnx,axi-mcdma-1.00.a", .data = &aximcdma_config },
3001 	{}
3002 };
3003 MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
3004 
3005 /**
3006  * xilinx_dma_probe - Driver probe function
3007  * @pdev: Pointer to the platform_device structure
3008  *
3009  * Return: '0' on success and failure value on error
3010  */
3011 static int xilinx_dma_probe(struct platform_device *pdev)
3012 {
3013 	int (*clk_init)(struct platform_device *, struct clk **, struct clk **,
3014 			struct clk **, struct clk **, struct clk **)
3015 					= axivdma_clk_init;
3016 	struct device_node *node = pdev->dev.of_node;
3017 	struct xilinx_dma_device *xdev;
3018 	struct device_node *child, *np = pdev->dev.of_node;
3019 	u32 num_frames, addr_width, len_width;
3020 	int i, err;
3021 
3022 	/* Allocate and initialize the DMA engine structure */
3023 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
3024 	if (!xdev)
3025 		return -ENOMEM;
3026 
3027 	xdev->dev = &pdev->dev;
3028 	if (np) {
3029 		const struct of_device_id *match;
3030 
3031 		match = of_match_node(xilinx_dma_of_ids, np);
3032 		if (match && match->data) {
3033 			xdev->dma_config = match->data;
3034 			clk_init = xdev->dma_config->clk_init;
3035 		}
3036 	}
3037 
3038 	err = clk_init(pdev, &xdev->axi_clk, &xdev->tx_clk, &xdev->txs_clk,
3039 		       &xdev->rx_clk, &xdev->rxs_clk);
3040 	if (err)
3041 		return err;
3042 
3043 	/* Request and map I/O memory */
3044 	xdev->regs = devm_platform_ioremap_resource(pdev, 0);
3045 	if (IS_ERR(xdev->regs)) {
3046 		err = PTR_ERR(xdev->regs);
3047 		goto disable_clks;
3048 	}
3049 	/* Retrieve the DMA engine properties from the device tree */
3050 	xdev->max_buffer_len = GENMASK(XILINX_DMA_MAX_TRANS_LEN_MAX - 1, 0);
3051 	xdev->s2mm_chan_id = xdev->dma_config->max_channels / 2;
3052 
3053 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA ||
3054 	    xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3055 		if (!of_property_read_u32(node, "xlnx,sg-length-width",
3056 					  &len_width)) {
3057 			if (len_width < XILINX_DMA_MAX_TRANS_LEN_MIN ||
3058 			    len_width > XILINX_DMA_V2_MAX_TRANS_LEN_MAX) {
3059 				dev_warn(xdev->dev,
3060 					 "invalid xlnx,sg-length-width property value. Using default width\n");
3061 			} else {
3062 				if (len_width > XILINX_DMA_MAX_TRANS_LEN_MAX)
3063 					dev_warn(xdev->dev, "Please ensure that IP supports buffer length > 23 bits\n");
3064 				xdev->max_buffer_len =
3065 					GENMASK(len_width - 1, 0);
3066 			}
3067 		}
3068 	}
3069 
3070 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3071 		err = of_property_read_u32(node, "xlnx,num-fstores",
3072 					   &num_frames);
3073 		if (err < 0) {
3074 			dev_err(xdev->dev,
3075 				"missing xlnx,num-fstores property\n");
3076 			goto disable_clks;
3077 		}
3078 
3079 		err = of_property_read_u32(node, "xlnx,flush-fsync",
3080 					   &xdev->flush_on_fsync);
3081 		if (err < 0)
3082 			dev_warn(xdev->dev,
3083 				 "missing xlnx,flush-fsync property\n");
3084 	}
3085 
3086 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
3087 	if (err < 0)
3088 		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
3089 
3090 	if (addr_width > 32)
3091 		xdev->ext_addr = true;
3092 	else
3093 		xdev->ext_addr = false;
3094 
3095 	/* Set the dma mask bits */
3096 	err = dma_set_mask_and_coherent(xdev->dev, DMA_BIT_MASK(addr_width));
3097 	if (err < 0) {
3098 		dev_err(xdev->dev, "DMA mask error %d\n", err);
3099 		goto disable_clks;
3100 	}
3101 
3102 	/* Initialize the DMA engine */
3103 	xdev->common.dev = &pdev->dev;
3104 
3105 	INIT_LIST_HEAD(&xdev->common.channels);
3106 	if (!(xdev->dma_config->dmatype == XDMA_TYPE_CDMA)) {
3107 		dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
3108 		dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
3109 	}
3110 
3111 	xdev->common.device_alloc_chan_resources =
3112 				xilinx_dma_alloc_chan_resources;
3113 	xdev->common.device_free_chan_resources =
3114 				xilinx_dma_free_chan_resources;
3115 	xdev->common.device_terminate_all = xilinx_dma_terminate_all;
3116 	xdev->common.device_synchronize = xilinx_dma_synchronize;
3117 	xdev->common.device_tx_status = xilinx_dma_tx_status;
3118 	xdev->common.device_issue_pending = xilinx_dma_issue_pending;
3119 	xdev->common.device_config = xilinx_dma_device_config;
3120 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3121 		dma_cap_set(DMA_CYCLIC, xdev->common.cap_mask);
3122 		xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
3123 		xdev->common.device_prep_dma_cyclic =
3124 					  xilinx_dma_prep_dma_cyclic;
3125 		/* Residue calculation is supported by only AXI DMA and CDMA */
3126 		xdev->common.residue_granularity =
3127 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3128 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
3129 		dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
3130 		xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
3131 		/* Residue calculation is supported by only AXI DMA and CDMA */
3132 		xdev->common.residue_granularity =
3133 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3134 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3135 		xdev->common.device_prep_slave_sg = xilinx_mcdma_prep_slave_sg;
3136 	} else {
3137 		xdev->common.device_prep_interleaved_dma =
3138 				xilinx_vdma_dma_prep_interleaved;
3139 	}
3140 
3141 	platform_set_drvdata(pdev, xdev);
3142 
3143 	/* Initialize the channels */
3144 	for_each_child_of_node(node, child) {
3145 		err = xilinx_dma_child_probe(xdev, child);
3146 		if (err < 0)
3147 			goto error;
3148 	}
3149 
3150 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3151 		for (i = 0; i < xdev->dma_config->max_channels; i++)
3152 			if (xdev->chan[i])
3153 				xdev->chan[i]->num_frms = num_frames;
3154 	}
3155 
3156 	/* Register the DMA engine with the core */
3157 	err = dma_async_device_register(&xdev->common);
3158 	if (err) {
3159 		dev_err(xdev->dev, "failed to register the dma device\n");
3160 		goto error;
3161 	}
3162 
3163 	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
3164 					 xdev);
3165 	if (err < 0) {
3166 		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
3167 		dma_async_device_unregister(&xdev->common);
3168 		goto error;
3169 	}
3170 
3171 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
3172 		dev_info(&pdev->dev, "Xilinx AXI DMA Engine Driver Probed!!\n");
3173 	else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA)
3174 		dev_info(&pdev->dev, "Xilinx AXI CDMA Engine Driver Probed!!\n");
3175 	else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
3176 		dev_info(&pdev->dev, "Xilinx AXI MCDMA Engine Driver Probed!!\n");
3177 	else
3178 		dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
3179 
3180 	return 0;
3181 
3182 error:
3183 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3184 		if (xdev->chan[i])
3185 			xilinx_dma_chan_remove(xdev->chan[i]);
3186 disable_clks:
3187 	xdma_disable_allclks(xdev);
3188 
3189 	return err;
3190 }
3191 
3192 /**
3193  * xilinx_dma_remove - Driver remove function
3194  * @pdev: Pointer to the platform_device structure
3195  *
3196  * Return: Always '0'
3197  */
3198 static int xilinx_dma_remove(struct platform_device *pdev)
3199 {
3200 	struct xilinx_dma_device *xdev = platform_get_drvdata(pdev);
3201 	int i;
3202 
3203 	of_dma_controller_free(pdev->dev.of_node);
3204 
3205 	dma_async_device_unregister(&xdev->common);
3206 
3207 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3208 		if (xdev->chan[i])
3209 			xilinx_dma_chan_remove(xdev->chan[i]);
3210 
3211 	xdma_disable_allclks(xdev);
3212 
3213 	return 0;
3214 }
3215 
3216 static struct platform_driver xilinx_vdma_driver = {
3217 	.driver = {
3218 		.name = "xilinx-vdma",
3219 		.of_match_table = xilinx_dma_of_ids,
3220 	},
3221 	.probe = xilinx_dma_probe,
3222 	.remove = xilinx_dma_remove,
3223 };
3224 
3225 module_platform_driver(xilinx_vdma_driver);
3226 
3227 MODULE_AUTHOR("Xilinx, Inc.");
3228 MODULE_DESCRIPTION("Xilinx VDMA driver");
3229 MODULE_LICENSE("GPL v2");
3230