xref: /openbmc/linux/drivers/dma/xilinx/xilinx_dma.c (revision dd21bfa4)
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 static int xilinx_dma_device_config(struct dma_chan *dchan,
1664 				    struct dma_slave_config *config)
1665 {
1666 	return 0;
1667 }
1668 
1669 /**
1670  * xilinx_dma_complete_descriptor - Mark the active descriptor as complete
1671  * @chan : xilinx DMA channel
1672  *
1673  * CONTEXT: hardirq
1674  */
1675 static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
1676 {
1677 	struct xilinx_dma_tx_descriptor *desc, *next;
1678 
1679 	/* This function was invoked with lock held */
1680 	if (list_empty(&chan->active_list))
1681 		return;
1682 
1683 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
1684 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
1685 		    XDMA_TYPE_VDMA)
1686 			desc->residue = xilinx_dma_get_residue(chan, desc);
1687 		else
1688 			desc->residue = 0;
1689 		desc->err = chan->err;
1690 
1691 		list_del(&desc->node);
1692 		if (!desc->cyclic)
1693 			dma_cookie_complete(&desc->async_tx);
1694 		list_add_tail(&desc->node, &chan->done_list);
1695 	}
1696 }
1697 
1698 /**
1699  * xilinx_dma_reset - Reset DMA channel
1700  * @chan: Driver specific DMA channel
1701  *
1702  * Return: '0' on success and failure value on error
1703  */
1704 static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
1705 {
1706 	int err;
1707 	u32 tmp;
1708 
1709 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RESET);
1710 
1711 	/* Wait for the hardware to finish reset */
1712 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMACR, tmp,
1713 				      !(tmp & XILINX_DMA_DMACR_RESET), 0,
1714 				      XILINX_DMA_LOOP_COUNT);
1715 
1716 	if (err) {
1717 		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
1718 			dma_ctrl_read(chan, XILINX_DMA_REG_DMACR),
1719 			dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1720 		return -ETIMEDOUT;
1721 	}
1722 
1723 	chan->err = false;
1724 	chan->idle = true;
1725 	chan->desc_pendingcount = 0;
1726 	chan->desc_submitcount = 0;
1727 
1728 	return err;
1729 }
1730 
1731 /**
1732  * xilinx_dma_chan_reset - Reset DMA channel and enable interrupts
1733  * @chan: Driver specific DMA channel
1734  *
1735  * Return: '0' on success and failure value on error
1736  */
1737 static int xilinx_dma_chan_reset(struct xilinx_dma_chan *chan)
1738 {
1739 	int err;
1740 
1741 	/* Reset VDMA */
1742 	err = xilinx_dma_reset(chan);
1743 	if (err)
1744 		return err;
1745 
1746 	/* Enable interrupts */
1747 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1748 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1749 
1750 	return 0;
1751 }
1752 
1753 /**
1754  * xilinx_mcdma_irq_handler - MCDMA Interrupt handler
1755  * @irq: IRQ number
1756  * @data: Pointer to the Xilinx MCDMA channel structure
1757  *
1758  * Return: IRQ_HANDLED/IRQ_NONE
1759  */
1760 static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
1761 {
1762 	struct xilinx_dma_chan *chan = data;
1763 	u32 status, ser_offset, chan_sermask, chan_offset = 0, chan_id;
1764 
1765 	if (chan->direction == DMA_DEV_TO_MEM)
1766 		ser_offset = XILINX_MCDMA_RXINT_SER_OFFSET;
1767 	else
1768 		ser_offset = XILINX_MCDMA_TXINT_SER_OFFSET;
1769 
1770 	/* Read the channel id raising the interrupt*/
1771 	chan_sermask = dma_ctrl_read(chan, ser_offset);
1772 	chan_id = ffs(chan_sermask);
1773 
1774 	if (!chan_id)
1775 		return IRQ_NONE;
1776 
1777 	if (chan->direction == DMA_DEV_TO_MEM)
1778 		chan_offset = chan->xdev->dma_config->max_channels / 2;
1779 
1780 	chan_offset = chan_offset + (chan_id - 1);
1781 	chan = chan->xdev->chan[chan_offset];
1782 	/* Read the status and ack the interrupts. */
1783 	status = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest));
1784 	if (!(status & XILINX_MCDMA_IRQ_ALL_MASK))
1785 		return IRQ_NONE;
1786 
1787 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest),
1788 		       status & XILINX_MCDMA_IRQ_ALL_MASK);
1789 
1790 	if (status & XILINX_MCDMA_IRQ_ERR_MASK) {
1791 		dev_err(chan->dev, "Channel %p has errors %x cdr %x tdr %x\n",
1792 			chan,
1793 			dma_ctrl_read(chan, XILINX_MCDMA_CH_ERR_OFFSET),
1794 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET
1795 				      (chan->tdest)),
1796 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET
1797 				      (chan->tdest)));
1798 		chan->err = true;
1799 	}
1800 
1801 	if (status & XILINX_MCDMA_IRQ_DELAY_MASK) {
1802 		/*
1803 		 * Device takes too long to do the transfer when user requires
1804 		 * responsiveness.
1805 		 */
1806 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1807 	}
1808 
1809 	if (status & XILINX_MCDMA_IRQ_IOC_MASK) {
1810 		spin_lock(&chan->lock);
1811 		xilinx_dma_complete_descriptor(chan);
1812 		chan->idle = true;
1813 		chan->start_transfer(chan);
1814 		spin_unlock(&chan->lock);
1815 	}
1816 
1817 	tasklet_schedule(&chan->tasklet);
1818 	return IRQ_HANDLED;
1819 }
1820 
1821 /**
1822  * xilinx_dma_irq_handler - DMA Interrupt handler
1823  * @irq: IRQ number
1824  * @data: Pointer to the Xilinx DMA channel structure
1825  *
1826  * Return: IRQ_HANDLED/IRQ_NONE
1827  */
1828 static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
1829 {
1830 	struct xilinx_dma_chan *chan = data;
1831 	u32 status;
1832 
1833 	/* Read the status and ack the interrupts. */
1834 	status = dma_ctrl_read(chan, XILINX_DMA_REG_DMASR);
1835 	if (!(status & XILINX_DMA_DMAXR_ALL_IRQ_MASK))
1836 		return IRQ_NONE;
1837 
1838 	dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1839 			status & XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1840 
1841 	if (status & XILINX_DMA_DMASR_ERR_IRQ) {
1842 		/*
1843 		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
1844 		 * error is recoverable, ignore it. Otherwise flag the error.
1845 		 *
1846 		 * Only recoverable errors can be cleared in the DMASR register,
1847 		 * make sure not to write to other error bits to 1.
1848 		 */
1849 		u32 errors = status & XILINX_DMA_DMASR_ALL_ERR_MASK;
1850 
1851 		dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1852 				errors & XILINX_DMA_DMASR_ERR_RECOVER_MASK);
1853 
1854 		if (!chan->flush_on_fsync ||
1855 		    (errors & ~XILINX_DMA_DMASR_ERR_RECOVER_MASK)) {
1856 			dev_err(chan->dev,
1857 				"Channel %p has errors %x, cdr %x tdr %x\n",
1858 				chan, errors,
1859 				dma_ctrl_read(chan, XILINX_DMA_REG_CURDESC),
1860 				dma_ctrl_read(chan, XILINX_DMA_REG_TAILDESC));
1861 			chan->err = true;
1862 		}
1863 	}
1864 
1865 	if (status & XILINX_DMA_DMASR_DLY_CNT_IRQ) {
1866 		/*
1867 		 * Device takes too long to do the transfer when user requires
1868 		 * responsiveness.
1869 		 */
1870 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1871 	}
1872 
1873 	if (status & XILINX_DMA_DMASR_FRM_CNT_IRQ) {
1874 		spin_lock(&chan->lock);
1875 		xilinx_dma_complete_descriptor(chan);
1876 		chan->idle = true;
1877 		chan->start_transfer(chan);
1878 		spin_unlock(&chan->lock);
1879 	}
1880 
1881 	tasklet_schedule(&chan->tasklet);
1882 	return IRQ_HANDLED;
1883 }
1884 
1885 /**
1886  * append_desc_queue - Queuing descriptor
1887  * @chan: Driver specific dma channel
1888  * @desc: dma transaction descriptor
1889  */
1890 static void append_desc_queue(struct xilinx_dma_chan *chan,
1891 			      struct xilinx_dma_tx_descriptor *desc)
1892 {
1893 	struct xilinx_vdma_tx_segment *tail_segment;
1894 	struct xilinx_dma_tx_descriptor *tail_desc;
1895 	struct xilinx_axidma_tx_segment *axidma_tail_segment;
1896 	struct xilinx_aximcdma_tx_segment *aximcdma_tail_segment;
1897 	struct xilinx_cdma_tx_segment *cdma_tail_segment;
1898 
1899 	if (list_empty(&chan->pending_list))
1900 		goto append;
1901 
1902 	/*
1903 	 * Add the hardware descriptor to the chain of hardware descriptors
1904 	 * that already exists in memory.
1905 	 */
1906 	tail_desc = list_last_entry(&chan->pending_list,
1907 				    struct xilinx_dma_tx_descriptor, node);
1908 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
1909 		tail_segment = list_last_entry(&tail_desc->segments,
1910 					       struct xilinx_vdma_tx_segment,
1911 					       node);
1912 		tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1913 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1914 		cdma_tail_segment = list_last_entry(&tail_desc->segments,
1915 						struct xilinx_cdma_tx_segment,
1916 						node);
1917 		cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1918 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1919 		axidma_tail_segment = list_last_entry(&tail_desc->segments,
1920 					       struct xilinx_axidma_tx_segment,
1921 					       node);
1922 		axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1923 	} else {
1924 		aximcdma_tail_segment =
1925 			list_last_entry(&tail_desc->segments,
1926 					struct xilinx_aximcdma_tx_segment,
1927 					node);
1928 		aximcdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1929 	}
1930 
1931 	/*
1932 	 * Add the software descriptor and all children to the list
1933 	 * of pending transactions
1934 	 */
1935 append:
1936 	list_add_tail(&desc->node, &chan->pending_list);
1937 	chan->desc_pendingcount++;
1938 
1939 	if (chan->has_sg && (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA)
1940 	    && unlikely(chan->desc_pendingcount > chan->num_frms)) {
1941 		dev_dbg(chan->dev, "desc pendingcount is too high\n");
1942 		chan->desc_pendingcount = chan->num_frms;
1943 	}
1944 }
1945 
1946 /**
1947  * xilinx_dma_tx_submit - Submit DMA transaction
1948  * @tx: Async transaction descriptor
1949  *
1950  * Return: cookie value on success and failure value on error
1951  */
1952 static dma_cookie_t xilinx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
1953 {
1954 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
1955 	struct xilinx_dma_chan *chan = to_xilinx_chan(tx->chan);
1956 	dma_cookie_t cookie;
1957 	unsigned long flags;
1958 	int err;
1959 
1960 	if (chan->cyclic) {
1961 		xilinx_dma_free_tx_descriptor(chan, desc);
1962 		return -EBUSY;
1963 	}
1964 
1965 	if (chan->err) {
1966 		/*
1967 		 * If reset fails, need to hard reset the system.
1968 		 * Channel is no longer functional
1969 		 */
1970 		err = xilinx_dma_chan_reset(chan);
1971 		if (err < 0)
1972 			return err;
1973 	}
1974 
1975 	spin_lock_irqsave(&chan->lock, flags);
1976 
1977 	cookie = dma_cookie_assign(tx);
1978 
1979 	/* Put this transaction onto the tail of the pending queue */
1980 	append_desc_queue(chan, desc);
1981 
1982 	if (desc->cyclic)
1983 		chan->cyclic = true;
1984 
1985 	chan->terminating = false;
1986 
1987 	spin_unlock_irqrestore(&chan->lock, flags);
1988 
1989 	return cookie;
1990 }
1991 
1992 /**
1993  * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
1994  *	DMA_SLAVE transaction
1995  * @dchan: DMA channel
1996  * @xt: Interleaved template pointer
1997  * @flags: transfer ack flags
1998  *
1999  * Return: Async transaction descriptor on success and NULL on failure
2000  */
2001 static struct dma_async_tx_descriptor *
2002 xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
2003 				 struct dma_interleaved_template *xt,
2004 				 unsigned long flags)
2005 {
2006 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2007 	struct xilinx_dma_tx_descriptor *desc;
2008 	struct xilinx_vdma_tx_segment *segment;
2009 	struct xilinx_vdma_desc_hw *hw;
2010 
2011 	if (!is_slave_direction(xt->dir))
2012 		return NULL;
2013 
2014 	if (!xt->numf || !xt->sgl[0].size)
2015 		return NULL;
2016 
2017 	if (xt->frame_size != 1)
2018 		return NULL;
2019 
2020 	/* Allocate a transaction descriptor. */
2021 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2022 	if (!desc)
2023 		return NULL;
2024 
2025 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2026 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2027 	async_tx_ack(&desc->async_tx);
2028 
2029 	/* Allocate the link descriptor from DMA pool */
2030 	segment = xilinx_vdma_alloc_tx_segment(chan);
2031 	if (!segment)
2032 		goto error;
2033 
2034 	/* Fill in the hardware descriptor */
2035 	hw = &segment->hw;
2036 	hw->vsize = xt->numf;
2037 	hw->hsize = xt->sgl[0].size;
2038 	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
2039 			XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT;
2040 	hw->stride |= chan->config.frm_dly <<
2041 			XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
2042 
2043 	if (xt->dir != DMA_MEM_TO_DEV) {
2044 		if (chan->ext_addr) {
2045 			hw->buf_addr = lower_32_bits(xt->dst_start);
2046 			hw->buf_addr_msb = upper_32_bits(xt->dst_start);
2047 		} else {
2048 			hw->buf_addr = xt->dst_start;
2049 		}
2050 	} else {
2051 		if (chan->ext_addr) {
2052 			hw->buf_addr = lower_32_bits(xt->src_start);
2053 			hw->buf_addr_msb = upper_32_bits(xt->src_start);
2054 		} else {
2055 			hw->buf_addr = xt->src_start;
2056 		}
2057 	}
2058 
2059 	/* Insert the segment into the descriptor segments list. */
2060 	list_add_tail(&segment->node, &desc->segments);
2061 
2062 	/* Link the last hardware descriptor with the first. */
2063 	segment = list_first_entry(&desc->segments,
2064 				   struct xilinx_vdma_tx_segment, node);
2065 	desc->async_tx.phys = segment->phys;
2066 
2067 	return &desc->async_tx;
2068 
2069 error:
2070 	xilinx_dma_free_tx_descriptor(chan, desc);
2071 	return NULL;
2072 }
2073 
2074 /**
2075  * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
2076  * @dchan: DMA channel
2077  * @dma_dst: destination address
2078  * @dma_src: source address
2079  * @len: transfer length
2080  * @flags: transfer ack flags
2081  *
2082  * Return: Async transaction descriptor on success and NULL on failure
2083  */
2084 static struct dma_async_tx_descriptor *
2085 xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
2086 			dma_addr_t dma_src, size_t len, unsigned long flags)
2087 {
2088 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2089 	struct xilinx_dma_tx_descriptor *desc;
2090 	struct xilinx_cdma_tx_segment *segment;
2091 	struct xilinx_cdma_desc_hw *hw;
2092 
2093 	if (!len || len > chan->xdev->max_buffer_len)
2094 		return NULL;
2095 
2096 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2097 	if (!desc)
2098 		return NULL;
2099 
2100 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2101 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2102 
2103 	/* Allocate the link descriptor from DMA pool */
2104 	segment = xilinx_cdma_alloc_tx_segment(chan);
2105 	if (!segment)
2106 		goto error;
2107 
2108 	hw = &segment->hw;
2109 	hw->control = len;
2110 	hw->src_addr = dma_src;
2111 	hw->dest_addr = dma_dst;
2112 	if (chan->ext_addr) {
2113 		hw->src_addr_msb = upper_32_bits(dma_src);
2114 		hw->dest_addr_msb = upper_32_bits(dma_dst);
2115 	}
2116 
2117 	/* Insert the segment into the descriptor segments list. */
2118 	list_add_tail(&segment->node, &desc->segments);
2119 
2120 	desc->async_tx.phys = segment->phys;
2121 	hw->next_desc = segment->phys;
2122 
2123 	return &desc->async_tx;
2124 
2125 error:
2126 	xilinx_dma_free_tx_descriptor(chan, desc);
2127 	return NULL;
2128 }
2129 
2130 /**
2131  * xilinx_cdma_prep_memcpy_sg - prepare descriptors for a memcpy_sg transaction
2132  * @dchan: DMA channel
2133  * @dst_sg: Destination scatter list
2134  * @dst_sg_len: Number of entries in destination scatter list
2135  * @src_sg: Source scatter list
2136  * @src_sg_len: Number of entries in source scatter list
2137  * @flags: transfer ack flags
2138  *
2139  * Return: Async transaction descriptor on success and NULL on failure
2140  */
2141 static struct dma_async_tx_descriptor *xilinx_cdma_prep_memcpy_sg(
2142 			struct dma_chan *dchan, struct scatterlist *dst_sg,
2143 			unsigned int dst_sg_len, struct scatterlist *src_sg,
2144 			unsigned int src_sg_len, unsigned long flags)
2145 {
2146 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2147 	struct xilinx_dma_tx_descriptor *desc;
2148 	struct xilinx_cdma_tx_segment *segment, *prev = NULL;
2149 	struct xilinx_cdma_desc_hw *hw;
2150 	size_t len, dst_avail, src_avail;
2151 	dma_addr_t dma_dst, dma_src;
2152 
2153 	if (unlikely(dst_sg_len == 0 || src_sg_len == 0))
2154 		return NULL;
2155 
2156 	if (unlikely(!dst_sg  || !src_sg))
2157 		return NULL;
2158 
2159 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2160 	if (!desc)
2161 		return NULL;
2162 
2163 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2164 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2165 
2166 	dst_avail = sg_dma_len(dst_sg);
2167 	src_avail = sg_dma_len(src_sg);
2168 	/*
2169 	 * loop until there is either no more source or no more destination
2170 	 * scatterlist entry
2171 	 */
2172 	while (true) {
2173 		len = min_t(size_t, src_avail, dst_avail);
2174 		len = min_t(size_t, len, chan->xdev->max_buffer_len);
2175 		if (len == 0)
2176 			goto fetch;
2177 
2178 		/* Allocate the link descriptor from DMA pool */
2179 		segment = xilinx_cdma_alloc_tx_segment(chan);
2180 		if (!segment)
2181 			goto error;
2182 
2183 		dma_dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) -
2184 			dst_avail;
2185 		dma_src = sg_dma_address(src_sg) + sg_dma_len(src_sg) -
2186 			src_avail;
2187 		hw = &segment->hw;
2188 		hw->control = len;
2189 		hw->src_addr = dma_src;
2190 		hw->dest_addr = dma_dst;
2191 		if (chan->ext_addr) {
2192 			hw->src_addr_msb = upper_32_bits(dma_src);
2193 			hw->dest_addr_msb = upper_32_bits(dma_dst);
2194 		}
2195 
2196 		if (prev) {
2197 			prev->hw.next_desc = segment->phys;
2198 			if (chan->ext_addr)
2199 				prev->hw.next_desc_msb =
2200 					upper_32_bits(segment->phys);
2201 		}
2202 
2203 		prev = segment;
2204 		dst_avail -= len;
2205 		src_avail -= len;
2206 		list_add_tail(&segment->node, &desc->segments);
2207 
2208 fetch:
2209 		/* Fetch the next dst scatterlist entry */
2210 		if (dst_avail == 0) {
2211 			if (dst_sg_len == 0)
2212 				break;
2213 			dst_sg = sg_next(dst_sg);
2214 			if (dst_sg == NULL)
2215 				break;
2216 			dst_sg_len--;
2217 			dst_avail = sg_dma_len(dst_sg);
2218 		}
2219 		/* Fetch the next src scatterlist entry */
2220 		if (src_avail == 0) {
2221 			if (src_sg_len == 0)
2222 				break;
2223 			src_sg = sg_next(src_sg);
2224 			if (src_sg == NULL)
2225 				break;
2226 			src_sg_len--;
2227 			src_avail = sg_dma_len(src_sg);
2228 		}
2229 	}
2230 
2231 	if (list_empty(&desc->segments)) {
2232 		dev_err(chan->xdev->dev,
2233 			"%s: Zero-size SG transfer requested\n", __func__);
2234 		goto error;
2235 	}
2236 
2237 	/* Link the last hardware descriptor with the first. */
2238 	segment = list_first_entry(&desc->segments,
2239 				struct xilinx_cdma_tx_segment, node);
2240 	desc->async_tx.phys = segment->phys;
2241 	prev->hw.next_desc = segment->phys;
2242 
2243 	return &desc->async_tx;
2244 
2245 error:
2246 	xilinx_dma_free_tx_descriptor(chan, desc);
2247 	return NULL;
2248 }
2249 
2250 /**
2251  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2252  * @dchan: DMA channel
2253  * @sgl: scatterlist to transfer to/from
2254  * @sg_len: number of entries in @scatterlist
2255  * @direction: DMA direction
2256  * @flags: transfer ack flags
2257  * @context: APP words of the descriptor
2258  *
2259  * Return: Async transaction descriptor on success and NULL on failure
2260  */
2261 static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
2262 	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
2263 	enum dma_transfer_direction direction, unsigned long flags,
2264 	void *context)
2265 {
2266 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2267 	struct xilinx_dma_tx_descriptor *desc;
2268 	struct xilinx_axidma_tx_segment *segment = NULL;
2269 	u32 *app_w = (u32 *)context;
2270 	struct scatterlist *sg;
2271 	size_t copy;
2272 	size_t sg_used;
2273 	unsigned int i;
2274 
2275 	if (!is_slave_direction(direction))
2276 		return NULL;
2277 
2278 	/* Allocate a transaction descriptor. */
2279 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2280 	if (!desc)
2281 		return NULL;
2282 
2283 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2284 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2285 
2286 	/* Build transactions using information in the scatter gather list */
2287 	for_each_sg(sgl, sg, sg_len, i) {
2288 		sg_used = 0;
2289 
2290 		/* Loop until the entire scatterlist entry is used */
2291 		while (sg_used < sg_dma_len(sg)) {
2292 			struct xilinx_axidma_desc_hw *hw;
2293 
2294 			/* Get a free segment */
2295 			segment = xilinx_axidma_alloc_tx_segment(chan);
2296 			if (!segment)
2297 				goto error;
2298 
2299 			/*
2300 			 * Calculate the maximum number of bytes to transfer,
2301 			 * making sure it is less than the hw limit
2302 			 */
2303 			copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
2304 							sg_used);
2305 			hw = &segment->hw;
2306 
2307 			/* Fill in the descriptor */
2308 			xilinx_axidma_buf(chan, hw, sg_dma_address(sg),
2309 					  sg_used, 0);
2310 
2311 			hw->control = copy;
2312 
2313 			if (chan->direction == DMA_MEM_TO_DEV) {
2314 				if (app_w)
2315 					memcpy(hw->app, app_w, sizeof(u32) *
2316 					       XILINX_DMA_NUM_APP_WORDS);
2317 			}
2318 
2319 			sg_used += copy;
2320 
2321 			/*
2322 			 * Insert the segment into the descriptor segments
2323 			 * list.
2324 			 */
2325 			list_add_tail(&segment->node, &desc->segments);
2326 		}
2327 	}
2328 
2329 	segment = list_first_entry(&desc->segments,
2330 				   struct xilinx_axidma_tx_segment, node);
2331 	desc->async_tx.phys = segment->phys;
2332 
2333 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2334 	if (chan->direction == DMA_MEM_TO_DEV) {
2335 		segment->hw.control |= XILINX_DMA_BD_SOP;
2336 		segment = list_last_entry(&desc->segments,
2337 					  struct xilinx_axidma_tx_segment,
2338 					  node);
2339 		segment->hw.control |= XILINX_DMA_BD_EOP;
2340 	}
2341 
2342 	return &desc->async_tx;
2343 
2344 error:
2345 	xilinx_dma_free_tx_descriptor(chan, desc);
2346 	return NULL;
2347 }
2348 
2349 /**
2350  * xilinx_dma_prep_dma_cyclic - prepare descriptors for a DMA_SLAVE transaction
2351  * @dchan: DMA channel
2352  * @buf_addr: Physical address of the buffer
2353  * @buf_len: Total length of the cyclic buffers
2354  * @period_len: length of individual cyclic buffer
2355  * @direction: DMA direction
2356  * @flags: transfer ack flags
2357  *
2358  * Return: Async transaction descriptor on success and NULL on failure
2359  */
2360 static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
2361 	struct dma_chan *dchan, dma_addr_t buf_addr, size_t buf_len,
2362 	size_t period_len, enum dma_transfer_direction direction,
2363 	unsigned long flags)
2364 {
2365 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2366 	struct xilinx_dma_tx_descriptor *desc;
2367 	struct xilinx_axidma_tx_segment *segment, *head_segment, *prev = NULL;
2368 	size_t copy, sg_used;
2369 	unsigned int num_periods;
2370 	int i;
2371 	u32 reg;
2372 
2373 	if (!period_len)
2374 		return NULL;
2375 
2376 	num_periods = buf_len / period_len;
2377 
2378 	if (!num_periods)
2379 		return NULL;
2380 
2381 	if (!is_slave_direction(direction))
2382 		return NULL;
2383 
2384 	/* Allocate a transaction descriptor. */
2385 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2386 	if (!desc)
2387 		return NULL;
2388 
2389 	chan->direction = direction;
2390 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2391 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2392 
2393 	for (i = 0; i < num_periods; ++i) {
2394 		sg_used = 0;
2395 
2396 		while (sg_used < period_len) {
2397 			struct xilinx_axidma_desc_hw *hw;
2398 
2399 			/* Get a free segment */
2400 			segment = xilinx_axidma_alloc_tx_segment(chan);
2401 			if (!segment)
2402 				goto error;
2403 
2404 			/*
2405 			 * Calculate the maximum number of bytes to transfer,
2406 			 * making sure it is less than the hw limit
2407 			 */
2408 			copy = xilinx_dma_calc_copysize(chan, period_len,
2409 							sg_used);
2410 			hw = &segment->hw;
2411 			xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
2412 					  period_len * i);
2413 			hw->control = copy;
2414 
2415 			if (prev)
2416 				prev->hw.next_desc = segment->phys;
2417 
2418 			prev = segment;
2419 			sg_used += copy;
2420 
2421 			/*
2422 			 * Insert the segment into the descriptor segments
2423 			 * list.
2424 			 */
2425 			list_add_tail(&segment->node, &desc->segments);
2426 		}
2427 	}
2428 
2429 	head_segment = list_first_entry(&desc->segments,
2430 				   struct xilinx_axidma_tx_segment, node);
2431 	desc->async_tx.phys = head_segment->phys;
2432 
2433 	desc->cyclic = true;
2434 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2435 	reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2436 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2437 
2438 	segment = list_last_entry(&desc->segments,
2439 				  struct xilinx_axidma_tx_segment,
2440 				  node);
2441 	segment->hw.next_desc = (u32) head_segment->phys;
2442 
2443 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2444 	if (direction == DMA_MEM_TO_DEV) {
2445 		head_segment->hw.control |= XILINX_DMA_BD_SOP;
2446 		segment->hw.control |= XILINX_DMA_BD_EOP;
2447 	}
2448 
2449 	return &desc->async_tx;
2450 
2451 error:
2452 	xilinx_dma_free_tx_descriptor(chan, desc);
2453 	return NULL;
2454 }
2455 
2456 /**
2457  * xilinx_mcdma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2458  * @dchan: DMA channel
2459  * @sgl: scatterlist to transfer to/from
2460  * @sg_len: number of entries in @scatterlist
2461  * @direction: DMA direction
2462  * @flags: transfer ack flags
2463  * @context: APP words of the descriptor
2464  *
2465  * Return: Async transaction descriptor on success and NULL on failure
2466  */
2467 static struct dma_async_tx_descriptor *
2468 xilinx_mcdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
2469 			   unsigned int sg_len,
2470 			   enum dma_transfer_direction direction,
2471 			   unsigned long flags, void *context)
2472 {
2473 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2474 	struct xilinx_dma_tx_descriptor *desc;
2475 	struct xilinx_aximcdma_tx_segment *segment = NULL;
2476 	u32 *app_w = (u32 *)context;
2477 	struct scatterlist *sg;
2478 	size_t copy;
2479 	size_t sg_used;
2480 	unsigned int i;
2481 
2482 	if (!is_slave_direction(direction))
2483 		return NULL;
2484 
2485 	/* Allocate a transaction descriptor. */
2486 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2487 	if (!desc)
2488 		return NULL;
2489 
2490 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2491 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2492 
2493 	/* Build transactions using information in the scatter gather list */
2494 	for_each_sg(sgl, sg, sg_len, i) {
2495 		sg_used = 0;
2496 
2497 		/* Loop until the entire scatterlist entry is used */
2498 		while (sg_used < sg_dma_len(sg)) {
2499 			struct xilinx_aximcdma_desc_hw *hw;
2500 
2501 			/* Get a free segment */
2502 			segment = xilinx_aximcdma_alloc_tx_segment(chan);
2503 			if (!segment)
2504 				goto error;
2505 
2506 			/*
2507 			 * Calculate the maximum number of bytes to transfer,
2508 			 * making sure it is less than the hw limit
2509 			 */
2510 			copy = min_t(size_t, sg_dma_len(sg) - sg_used,
2511 				     chan->xdev->max_buffer_len);
2512 			hw = &segment->hw;
2513 
2514 			/* Fill in the descriptor */
2515 			xilinx_aximcdma_buf(chan, hw, sg_dma_address(sg),
2516 					    sg_used);
2517 			hw->control = copy;
2518 
2519 			if (chan->direction == DMA_MEM_TO_DEV && app_w) {
2520 				memcpy(hw->app, app_w, sizeof(u32) *
2521 				       XILINX_DMA_NUM_APP_WORDS);
2522 			}
2523 
2524 			sg_used += copy;
2525 			/*
2526 			 * Insert the segment into the descriptor segments
2527 			 * list.
2528 			 */
2529 			list_add_tail(&segment->node, &desc->segments);
2530 		}
2531 	}
2532 
2533 	segment = list_first_entry(&desc->segments,
2534 				   struct xilinx_aximcdma_tx_segment, node);
2535 	desc->async_tx.phys = segment->phys;
2536 
2537 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2538 	if (chan->direction == DMA_MEM_TO_DEV) {
2539 		segment->hw.control |= XILINX_MCDMA_BD_SOP;
2540 		segment = list_last_entry(&desc->segments,
2541 					  struct xilinx_aximcdma_tx_segment,
2542 					  node);
2543 		segment->hw.control |= XILINX_MCDMA_BD_EOP;
2544 	}
2545 
2546 	return &desc->async_tx;
2547 
2548 error:
2549 	xilinx_dma_free_tx_descriptor(chan, desc);
2550 
2551 	return NULL;
2552 }
2553 
2554 /**
2555  * xilinx_dma_terminate_all - Halt the channel and free descriptors
2556  * @dchan: Driver specific DMA Channel pointer
2557  *
2558  * Return: '0' always.
2559  */
2560 static int xilinx_dma_terminate_all(struct dma_chan *dchan)
2561 {
2562 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2563 	u32 reg;
2564 	int err;
2565 
2566 	if (!chan->cyclic) {
2567 		err = chan->stop_transfer(chan);
2568 		if (err) {
2569 			dev_err(chan->dev, "Cannot stop channel %p: %x\n",
2570 				chan, dma_ctrl_read(chan,
2571 				XILINX_DMA_REG_DMASR));
2572 			chan->err = true;
2573 		}
2574 	}
2575 
2576 	xilinx_dma_chan_reset(chan);
2577 	/* Remove and free all of the descriptors in the lists */
2578 	chan->terminating = true;
2579 	xilinx_dma_free_descriptors(chan);
2580 	chan->idle = true;
2581 
2582 	if (chan->cyclic) {
2583 		reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2584 		reg &= ~XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2585 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2586 		chan->cyclic = false;
2587 	}
2588 
2589 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
2590 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2591 			     XILINX_CDMA_CR_SGMODE);
2592 
2593 	return 0;
2594 }
2595 
2596 static void xilinx_dma_synchronize(struct dma_chan *dchan)
2597 {
2598 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2599 
2600 	tasklet_kill(&chan->tasklet);
2601 }
2602 
2603 /**
2604  * xilinx_vdma_channel_set_config - Configure VDMA channel
2605  * Run-time configuration for Axi VDMA, supports:
2606  * . halt the channel
2607  * . configure interrupt coalescing and inter-packet delay threshold
2608  * . start/stop parking
2609  * . enable genlock
2610  *
2611  * @dchan: DMA channel
2612  * @cfg: VDMA device configuration pointer
2613  *
2614  * Return: '0' on success and failure value on error
2615  */
2616 int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
2617 					struct xilinx_vdma_config *cfg)
2618 {
2619 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2620 	u32 dmacr;
2621 
2622 	if (cfg->reset)
2623 		return xilinx_dma_chan_reset(chan);
2624 
2625 	dmacr = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2626 
2627 	chan->config.frm_dly = cfg->frm_dly;
2628 	chan->config.park = cfg->park;
2629 
2630 	/* genlock settings */
2631 	chan->config.gen_lock = cfg->gen_lock;
2632 	chan->config.master = cfg->master;
2633 
2634 	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
2635 	if (cfg->gen_lock && chan->genlock) {
2636 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
2637 		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
2638 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
2639 	}
2640 
2641 	chan->config.frm_cnt_en = cfg->frm_cnt_en;
2642 	chan->config.vflip_en = cfg->vflip_en;
2643 
2644 	if (cfg->park)
2645 		chan->config.park_frm = cfg->park_frm;
2646 	else
2647 		chan->config.park_frm = -1;
2648 
2649 	chan->config.coalesc = cfg->coalesc;
2650 	chan->config.delay = cfg->delay;
2651 
2652 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
2653 		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
2654 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
2655 		chan->config.coalesc = cfg->coalesc;
2656 	}
2657 
2658 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
2659 		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
2660 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
2661 		chan->config.delay = cfg->delay;
2662 	}
2663 
2664 	/* FSync Source selection */
2665 	dmacr &= ~XILINX_DMA_DMACR_FSYNCSRC_MASK;
2666 	dmacr |= cfg->ext_fsync << XILINX_DMA_DMACR_FSYNCSRC_SHIFT;
2667 
2668 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, dmacr);
2669 
2670 	return 0;
2671 }
2672 EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
2673 
2674 /* -----------------------------------------------------------------------------
2675  * Probe and remove
2676  */
2677 
2678 /**
2679  * xilinx_dma_chan_remove - Per Channel remove function
2680  * @chan: Driver specific DMA channel
2681  */
2682 static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
2683 {
2684 	/* Disable all interrupts */
2685 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2686 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
2687 
2688 	if (chan->irq > 0)
2689 		free_irq(chan->irq, chan);
2690 
2691 	tasklet_kill(&chan->tasklet);
2692 
2693 	list_del(&chan->common.device_node);
2694 }
2695 
2696 static int axidma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2697 			    struct clk **tx_clk, struct clk **rx_clk,
2698 			    struct clk **sg_clk, struct clk **tmp_clk)
2699 {
2700 	int err;
2701 
2702 	*tmp_clk = NULL;
2703 
2704 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2705 	if (IS_ERR(*axi_clk))
2706 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2707 
2708 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2709 	if (IS_ERR(*tx_clk))
2710 		*tx_clk = NULL;
2711 
2712 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2713 	if (IS_ERR(*rx_clk))
2714 		*rx_clk = NULL;
2715 
2716 	*sg_clk = devm_clk_get(&pdev->dev, "m_axi_sg_aclk");
2717 	if (IS_ERR(*sg_clk))
2718 		*sg_clk = NULL;
2719 
2720 	err = clk_prepare_enable(*axi_clk);
2721 	if (err) {
2722 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2723 		return err;
2724 	}
2725 
2726 	err = clk_prepare_enable(*tx_clk);
2727 	if (err) {
2728 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2729 		goto err_disable_axiclk;
2730 	}
2731 
2732 	err = clk_prepare_enable(*rx_clk);
2733 	if (err) {
2734 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2735 		goto err_disable_txclk;
2736 	}
2737 
2738 	err = clk_prepare_enable(*sg_clk);
2739 	if (err) {
2740 		dev_err(&pdev->dev, "failed to enable sg_clk (%d)\n", err);
2741 		goto err_disable_rxclk;
2742 	}
2743 
2744 	return 0;
2745 
2746 err_disable_rxclk:
2747 	clk_disable_unprepare(*rx_clk);
2748 err_disable_txclk:
2749 	clk_disable_unprepare(*tx_clk);
2750 err_disable_axiclk:
2751 	clk_disable_unprepare(*axi_clk);
2752 
2753 	return err;
2754 }
2755 
2756 static int axicdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2757 			    struct clk **dev_clk, struct clk **tmp_clk,
2758 			    struct clk **tmp1_clk, struct clk **tmp2_clk)
2759 {
2760 	int err;
2761 
2762 	*tmp_clk = NULL;
2763 	*tmp1_clk = NULL;
2764 	*tmp2_clk = NULL;
2765 
2766 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2767 	if (IS_ERR(*axi_clk))
2768 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2769 
2770 	*dev_clk = devm_clk_get(&pdev->dev, "m_axi_aclk");
2771 	if (IS_ERR(*dev_clk))
2772 		return dev_err_probe(&pdev->dev, PTR_ERR(*dev_clk), "failed to get dev_clk\n");
2773 
2774 	err = clk_prepare_enable(*axi_clk);
2775 	if (err) {
2776 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2777 		return err;
2778 	}
2779 
2780 	err = clk_prepare_enable(*dev_clk);
2781 	if (err) {
2782 		dev_err(&pdev->dev, "failed to enable dev_clk (%d)\n", err);
2783 		goto err_disable_axiclk;
2784 	}
2785 
2786 	return 0;
2787 
2788 err_disable_axiclk:
2789 	clk_disable_unprepare(*axi_clk);
2790 
2791 	return err;
2792 }
2793 
2794 static int axivdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2795 			    struct clk **tx_clk, struct clk **txs_clk,
2796 			    struct clk **rx_clk, struct clk **rxs_clk)
2797 {
2798 	int err;
2799 
2800 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2801 	if (IS_ERR(*axi_clk))
2802 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2803 
2804 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2805 	if (IS_ERR(*tx_clk))
2806 		*tx_clk = NULL;
2807 
2808 	*txs_clk = devm_clk_get(&pdev->dev, "m_axis_mm2s_aclk");
2809 	if (IS_ERR(*txs_clk))
2810 		*txs_clk = NULL;
2811 
2812 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2813 	if (IS_ERR(*rx_clk))
2814 		*rx_clk = NULL;
2815 
2816 	*rxs_clk = devm_clk_get(&pdev->dev, "s_axis_s2mm_aclk");
2817 	if (IS_ERR(*rxs_clk))
2818 		*rxs_clk = NULL;
2819 
2820 	err = clk_prepare_enable(*axi_clk);
2821 	if (err) {
2822 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n",
2823 			err);
2824 		return err;
2825 	}
2826 
2827 	err = clk_prepare_enable(*tx_clk);
2828 	if (err) {
2829 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2830 		goto err_disable_axiclk;
2831 	}
2832 
2833 	err = clk_prepare_enable(*txs_clk);
2834 	if (err) {
2835 		dev_err(&pdev->dev, "failed to enable txs_clk (%d)\n", err);
2836 		goto err_disable_txclk;
2837 	}
2838 
2839 	err = clk_prepare_enable(*rx_clk);
2840 	if (err) {
2841 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2842 		goto err_disable_txsclk;
2843 	}
2844 
2845 	err = clk_prepare_enable(*rxs_clk);
2846 	if (err) {
2847 		dev_err(&pdev->dev, "failed to enable rxs_clk (%d)\n", err);
2848 		goto err_disable_rxclk;
2849 	}
2850 
2851 	return 0;
2852 
2853 err_disable_rxclk:
2854 	clk_disable_unprepare(*rx_clk);
2855 err_disable_txsclk:
2856 	clk_disable_unprepare(*txs_clk);
2857 err_disable_txclk:
2858 	clk_disable_unprepare(*tx_clk);
2859 err_disable_axiclk:
2860 	clk_disable_unprepare(*axi_clk);
2861 
2862 	return err;
2863 }
2864 
2865 static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
2866 {
2867 	clk_disable_unprepare(xdev->rxs_clk);
2868 	clk_disable_unprepare(xdev->rx_clk);
2869 	clk_disable_unprepare(xdev->txs_clk);
2870 	clk_disable_unprepare(xdev->tx_clk);
2871 	clk_disable_unprepare(xdev->axi_clk);
2872 }
2873 
2874 /**
2875  * xilinx_dma_chan_probe - Per Channel Probing
2876  * It get channel features from the device tree entry and
2877  * initialize special channel handling routines
2878  *
2879  * @xdev: Driver specific device structure
2880  * @node: Device node
2881  *
2882  * Return: '0' on success and failure value on error
2883  */
2884 static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
2885 				  struct device_node *node)
2886 {
2887 	struct xilinx_dma_chan *chan;
2888 	bool has_dre = false;
2889 	u32 value, width;
2890 	int err;
2891 
2892 	/* Allocate and initialize the channel structure */
2893 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
2894 	if (!chan)
2895 		return -ENOMEM;
2896 
2897 	chan->dev = xdev->dev;
2898 	chan->xdev = xdev;
2899 	chan->desc_pendingcount = 0x0;
2900 	chan->ext_addr = xdev->ext_addr;
2901 	/* This variable ensures that descriptors are not
2902 	 * Submitted when dma engine is in progress. This variable is
2903 	 * Added to avoid polling for a bit in the status register to
2904 	 * Know dma state in the driver hot path.
2905 	 */
2906 	chan->idle = true;
2907 
2908 	spin_lock_init(&chan->lock);
2909 	INIT_LIST_HEAD(&chan->pending_list);
2910 	INIT_LIST_HEAD(&chan->done_list);
2911 	INIT_LIST_HEAD(&chan->active_list);
2912 	INIT_LIST_HEAD(&chan->free_seg_list);
2913 
2914 	/* Retrieve the channel properties from the device tree */
2915 	has_dre = of_property_read_bool(node, "xlnx,include-dre");
2916 
2917 	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
2918 
2919 	err = of_property_read_u32(node, "xlnx,datawidth", &value);
2920 	if (err) {
2921 		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
2922 		return err;
2923 	}
2924 	width = value >> 3; /* Convert bits to bytes */
2925 
2926 	/* If data width is greater than 8 bytes, DRE is not in hw */
2927 	if (width > 8)
2928 		has_dre = false;
2929 
2930 	if (!has_dre)
2931 		xdev->common.copy_align = (enum dmaengine_alignment)fls(width - 1);
2932 
2933 	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel") ||
2934 	    of_device_is_compatible(node, "xlnx,axi-dma-mm2s-channel") ||
2935 	    of_device_is_compatible(node, "xlnx,axi-cdma-channel")) {
2936 		chan->direction = DMA_MEM_TO_DEV;
2937 		chan->id = xdev->mm2s_chan_id++;
2938 		chan->tdest = chan->id;
2939 
2940 		chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
2941 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2942 			chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
2943 			chan->config.park = 1;
2944 
2945 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2946 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
2947 				chan->flush_on_fsync = true;
2948 		}
2949 	} else if (of_device_is_compatible(node,
2950 					   "xlnx,axi-vdma-s2mm-channel") ||
2951 		   of_device_is_compatible(node,
2952 					   "xlnx,axi-dma-s2mm-channel")) {
2953 		chan->direction = DMA_DEV_TO_MEM;
2954 		chan->id = xdev->s2mm_chan_id++;
2955 		chan->tdest = chan->id - xdev->dma_config->max_channels / 2;
2956 		chan->has_vflip = of_property_read_bool(node,
2957 					"xlnx,enable-vert-flip");
2958 		if (chan->has_vflip) {
2959 			chan->config.vflip_en = dma_read(chan,
2960 				XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP) &
2961 				XILINX_VDMA_ENABLE_VERTICAL_FLIP;
2962 		}
2963 
2964 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
2965 			chan->ctrl_offset = XILINX_MCDMA_S2MM_CTRL_OFFSET;
2966 		else
2967 			chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
2968 
2969 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2970 			chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
2971 			chan->config.park = 1;
2972 
2973 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2974 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
2975 				chan->flush_on_fsync = true;
2976 		}
2977 	} else {
2978 		dev_err(xdev->dev, "Invalid channel compatible node\n");
2979 		return -EINVAL;
2980 	}
2981 
2982 	/* Request the interrupt */
2983 	chan->irq = of_irq_get(node, chan->tdest);
2984 	if (chan->irq < 0)
2985 		return dev_err_probe(xdev->dev, chan->irq, "failed to get irq\n");
2986 	err = request_irq(chan->irq, xdev->dma_config->irq_handler,
2987 			  IRQF_SHARED, "xilinx-dma-controller", chan);
2988 	if (err) {
2989 		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
2990 		return err;
2991 	}
2992 
2993 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
2994 		chan->start_transfer = xilinx_dma_start_transfer;
2995 		chan->stop_transfer = xilinx_dma_stop_transfer;
2996 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
2997 		chan->start_transfer = xilinx_mcdma_start_transfer;
2998 		chan->stop_transfer = xilinx_dma_stop_transfer;
2999 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
3000 		chan->start_transfer = xilinx_cdma_start_transfer;
3001 		chan->stop_transfer = xilinx_cdma_stop_transfer;
3002 	} else {
3003 		chan->start_transfer = xilinx_vdma_start_transfer;
3004 		chan->stop_transfer = xilinx_dma_stop_transfer;
3005 	}
3006 
3007 	/* check if SG is enabled (only for AXIDMA, AXIMCDMA, and CDMA) */
3008 	if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) {
3009 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA ||
3010 		    dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) &
3011 			    XILINX_DMA_DMASR_SG_MASK)
3012 			chan->has_sg = true;
3013 		dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id,
3014 			chan->has_sg ? "enabled" : "disabled");
3015 	}
3016 
3017 	/* Initialize the tasklet */
3018 	tasklet_setup(&chan->tasklet, xilinx_dma_do_tasklet);
3019 
3020 	/*
3021 	 * Initialize the DMA channel and add it to the DMA engine channels
3022 	 * list.
3023 	 */
3024 	chan->common.device = &xdev->common;
3025 
3026 	list_add_tail(&chan->common.device_node, &xdev->common.channels);
3027 	xdev->chan[chan->id] = chan;
3028 
3029 	/* Reset the channel */
3030 	err = xilinx_dma_chan_reset(chan);
3031 	if (err < 0) {
3032 		dev_err(xdev->dev, "Reset channel failed\n");
3033 		return err;
3034 	}
3035 
3036 	return 0;
3037 }
3038 
3039 /**
3040  * xilinx_dma_child_probe - Per child node probe
3041  * It get number of dma-channels per child node from
3042  * device-tree and initializes all the channels.
3043  *
3044  * @xdev: Driver specific device structure
3045  * @node: Device node
3046  *
3047  * Return: 0 always.
3048  */
3049 static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
3050 				    struct device_node *node)
3051 {
3052 	int ret, i;
3053 	u32 nr_channels = 1;
3054 
3055 	ret = of_property_read_u32(node, "dma-channels", &nr_channels);
3056 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA && ret < 0)
3057 		dev_warn(xdev->dev, "missing dma-channels property\n");
3058 
3059 	for (i = 0; i < nr_channels; i++) {
3060 		ret = xilinx_dma_chan_probe(xdev, node);
3061 		if (ret)
3062 			return ret;
3063 	}
3064 
3065 	return 0;
3066 }
3067 
3068 /**
3069  * of_dma_xilinx_xlate - Translation function
3070  * @dma_spec: Pointer to DMA specifier as found in the device tree
3071  * @ofdma: Pointer to DMA controller data
3072  *
3073  * Return: DMA channel pointer on success and NULL on error
3074  */
3075 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
3076 						struct of_dma *ofdma)
3077 {
3078 	struct xilinx_dma_device *xdev = ofdma->of_dma_data;
3079 	int chan_id = dma_spec->args[0];
3080 
3081 	if (chan_id >= xdev->dma_config->max_channels || !xdev->chan[chan_id])
3082 		return NULL;
3083 
3084 	return dma_get_slave_channel(&xdev->chan[chan_id]->common);
3085 }
3086 
3087 static const struct xilinx_dma_config axidma_config = {
3088 	.dmatype = XDMA_TYPE_AXIDMA,
3089 	.clk_init = axidma_clk_init,
3090 	.irq_handler = xilinx_dma_irq_handler,
3091 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3092 };
3093 
3094 static const struct xilinx_dma_config aximcdma_config = {
3095 	.dmatype = XDMA_TYPE_AXIMCDMA,
3096 	.clk_init = axidma_clk_init,
3097 	.irq_handler = xilinx_mcdma_irq_handler,
3098 	.max_channels = XILINX_MCDMA_MAX_CHANS_PER_DEVICE,
3099 };
3100 static const struct xilinx_dma_config axicdma_config = {
3101 	.dmatype = XDMA_TYPE_CDMA,
3102 	.clk_init = axicdma_clk_init,
3103 	.irq_handler = xilinx_dma_irq_handler,
3104 	.max_channels = XILINX_CDMA_MAX_CHANS_PER_DEVICE,
3105 };
3106 
3107 static const struct xilinx_dma_config axivdma_config = {
3108 	.dmatype = XDMA_TYPE_VDMA,
3109 	.clk_init = axivdma_clk_init,
3110 	.irq_handler = xilinx_dma_irq_handler,
3111 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3112 };
3113 
3114 static const struct of_device_id xilinx_dma_of_ids[] = {
3115 	{ .compatible = "xlnx,axi-dma-1.00.a", .data = &axidma_config },
3116 	{ .compatible = "xlnx,axi-cdma-1.00.a", .data = &axicdma_config },
3117 	{ .compatible = "xlnx,axi-vdma-1.00.a", .data = &axivdma_config },
3118 	{ .compatible = "xlnx,axi-mcdma-1.00.a", .data = &aximcdma_config },
3119 	{}
3120 };
3121 MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
3122 
3123 /**
3124  * xilinx_dma_probe - Driver probe function
3125  * @pdev: Pointer to the platform_device structure
3126  *
3127  * Return: '0' on success and failure value on error
3128  */
3129 static int xilinx_dma_probe(struct platform_device *pdev)
3130 {
3131 	int (*clk_init)(struct platform_device *, struct clk **, struct clk **,
3132 			struct clk **, struct clk **, struct clk **)
3133 					= axivdma_clk_init;
3134 	struct device_node *node = pdev->dev.of_node;
3135 	struct xilinx_dma_device *xdev;
3136 	struct device_node *child, *np = pdev->dev.of_node;
3137 	u32 num_frames, addr_width, len_width;
3138 	int i, err;
3139 
3140 	/* Allocate and initialize the DMA engine structure */
3141 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
3142 	if (!xdev)
3143 		return -ENOMEM;
3144 
3145 	xdev->dev = &pdev->dev;
3146 	if (np) {
3147 		const struct of_device_id *match;
3148 
3149 		match = of_match_node(xilinx_dma_of_ids, np);
3150 		if (match && match->data) {
3151 			xdev->dma_config = match->data;
3152 			clk_init = xdev->dma_config->clk_init;
3153 		}
3154 	}
3155 
3156 	err = clk_init(pdev, &xdev->axi_clk, &xdev->tx_clk, &xdev->txs_clk,
3157 		       &xdev->rx_clk, &xdev->rxs_clk);
3158 	if (err)
3159 		return err;
3160 
3161 	/* Request and map I/O memory */
3162 	xdev->regs = devm_platform_ioremap_resource(pdev, 0);
3163 	if (IS_ERR(xdev->regs))
3164 		return PTR_ERR(xdev->regs);
3165 
3166 	/* Retrieve the DMA engine properties from the device tree */
3167 	xdev->max_buffer_len = GENMASK(XILINX_DMA_MAX_TRANS_LEN_MAX - 1, 0);
3168 	xdev->s2mm_chan_id = xdev->dma_config->max_channels / 2;
3169 
3170 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA ||
3171 	    xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3172 		if (!of_property_read_u32(node, "xlnx,sg-length-width",
3173 					  &len_width)) {
3174 			if (len_width < XILINX_DMA_MAX_TRANS_LEN_MIN ||
3175 			    len_width > XILINX_DMA_V2_MAX_TRANS_LEN_MAX) {
3176 				dev_warn(xdev->dev,
3177 					 "invalid xlnx,sg-length-width property value. Using default width\n");
3178 			} else {
3179 				if (len_width > XILINX_DMA_MAX_TRANS_LEN_MAX)
3180 					dev_warn(xdev->dev, "Please ensure that IP supports buffer length > 23 bits\n");
3181 				xdev->max_buffer_len =
3182 					GENMASK(len_width - 1, 0);
3183 			}
3184 		}
3185 	}
3186 
3187 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3188 		err = of_property_read_u32(node, "xlnx,num-fstores",
3189 					   &num_frames);
3190 		if (err < 0) {
3191 			dev_err(xdev->dev,
3192 				"missing xlnx,num-fstores property\n");
3193 			return err;
3194 		}
3195 
3196 		err = of_property_read_u32(node, "xlnx,flush-fsync",
3197 					   &xdev->flush_on_fsync);
3198 		if (err < 0)
3199 			dev_warn(xdev->dev,
3200 				 "missing xlnx,flush-fsync property\n");
3201 	}
3202 
3203 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
3204 	if (err < 0)
3205 		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
3206 
3207 	if (addr_width > 32)
3208 		xdev->ext_addr = true;
3209 	else
3210 		xdev->ext_addr = false;
3211 
3212 	/* Set the dma mask bits */
3213 	dma_set_mask_and_coherent(xdev->dev, DMA_BIT_MASK(addr_width));
3214 
3215 	/* Initialize the DMA engine */
3216 	xdev->common.dev = &pdev->dev;
3217 
3218 	INIT_LIST_HEAD(&xdev->common.channels);
3219 	if (!(xdev->dma_config->dmatype == XDMA_TYPE_CDMA)) {
3220 		dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
3221 		dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
3222 	}
3223 
3224 	xdev->common.device_alloc_chan_resources =
3225 				xilinx_dma_alloc_chan_resources;
3226 	xdev->common.device_free_chan_resources =
3227 				xilinx_dma_free_chan_resources;
3228 	xdev->common.device_terminate_all = xilinx_dma_terminate_all;
3229 	xdev->common.device_synchronize = xilinx_dma_synchronize;
3230 	xdev->common.device_tx_status = xilinx_dma_tx_status;
3231 	xdev->common.device_issue_pending = xilinx_dma_issue_pending;
3232 	xdev->common.device_config = xilinx_dma_device_config;
3233 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3234 		dma_cap_set(DMA_CYCLIC, xdev->common.cap_mask);
3235 		xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
3236 		xdev->common.device_prep_dma_cyclic =
3237 					  xilinx_dma_prep_dma_cyclic;
3238 		/* Residue calculation is supported by only AXI DMA and CDMA */
3239 		xdev->common.residue_granularity =
3240 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3241 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
3242 		dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
3243 		dma_cap_set(DMA_MEMCPY_SG, xdev->common.cap_mask);
3244 		xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
3245 		xdev->common.device_prep_dma_memcpy_sg = xilinx_cdma_prep_memcpy_sg;
3246 		/* Residue calculation is supported by only AXI DMA and CDMA */
3247 		xdev->common.residue_granularity =
3248 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3249 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3250 		xdev->common.device_prep_slave_sg = xilinx_mcdma_prep_slave_sg;
3251 	} else {
3252 		xdev->common.device_prep_interleaved_dma =
3253 				xilinx_vdma_dma_prep_interleaved;
3254 	}
3255 
3256 	platform_set_drvdata(pdev, xdev);
3257 
3258 	/* Initialize the channels */
3259 	for_each_child_of_node(node, child) {
3260 		err = xilinx_dma_child_probe(xdev, child);
3261 		if (err < 0)
3262 			goto disable_clks;
3263 	}
3264 
3265 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3266 		for (i = 0; i < xdev->dma_config->max_channels; i++)
3267 			if (xdev->chan[i])
3268 				xdev->chan[i]->num_frms = num_frames;
3269 	}
3270 
3271 	/* Register the DMA engine with the core */
3272 	err = dma_async_device_register(&xdev->common);
3273 	if (err) {
3274 		dev_err(xdev->dev, "failed to register the dma device\n");
3275 		goto error;
3276 	}
3277 
3278 	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
3279 					 xdev);
3280 	if (err < 0) {
3281 		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
3282 		dma_async_device_unregister(&xdev->common);
3283 		goto error;
3284 	}
3285 
3286 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
3287 		dev_info(&pdev->dev, "Xilinx AXI DMA Engine Driver Probed!!\n");
3288 	else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA)
3289 		dev_info(&pdev->dev, "Xilinx AXI CDMA Engine Driver Probed!!\n");
3290 	else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
3291 		dev_info(&pdev->dev, "Xilinx AXI MCDMA Engine Driver Probed!!\n");
3292 	else
3293 		dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
3294 
3295 	return 0;
3296 
3297 disable_clks:
3298 	xdma_disable_allclks(xdev);
3299 error:
3300 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3301 		if (xdev->chan[i])
3302 			xilinx_dma_chan_remove(xdev->chan[i]);
3303 
3304 	return err;
3305 }
3306 
3307 /**
3308  * xilinx_dma_remove - Driver remove function
3309  * @pdev: Pointer to the platform_device structure
3310  *
3311  * Return: Always '0'
3312  */
3313 static int xilinx_dma_remove(struct platform_device *pdev)
3314 {
3315 	struct xilinx_dma_device *xdev = platform_get_drvdata(pdev);
3316 	int i;
3317 
3318 	of_dma_controller_free(pdev->dev.of_node);
3319 
3320 	dma_async_device_unregister(&xdev->common);
3321 
3322 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3323 		if (xdev->chan[i])
3324 			xilinx_dma_chan_remove(xdev->chan[i]);
3325 
3326 	xdma_disable_allclks(xdev);
3327 
3328 	return 0;
3329 }
3330 
3331 static struct platform_driver xilinx_vdma_driver = {
3332 	.driver = {
3333 		.name = "xilinx-vdma",
3334 		.of_match_table = xilinx_dma_of_ids,
3335 	},
3336 	.probe = xilinx_dma_probe,
3337 	.remove = xilinx_dma_remove,
3338 };
3339 
3340 module_platform_driver(xilinx_vdma_driver);
3341 
3342 MODULE_AUTHOR("Xilinx, Inc.");
3343 MODULE_DESCRIPTION("Xilinx VDMA driver");
3344 MODULE_LICENSE("GPL v2");
3345