xref: /openbmc/linux/drivers/dma/xilinx/xilinx_dma.c (revision 491e9d409629964457d094ac2b99e319d428dd1d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * DMA driver for Xilinx Video DMA Engine
4  *
5  * Copyright (C) 2010-2014 Xilinx, Inc. All rights reserved.
6  *
7  * Based on the Freescale DMA driver.
8  *
9  * Description:
10  * The AXI Video Direct Memory Access (AXI VDMA) core is a soft Xilinx IP
11  * core that provides high-bandwidth direct memory access between memory
12  * and AXI4-Stream type video target peripherals. The core provides efficient
13  * two dimensional DMA operations with independent asynchronous read (S2MM)
14  * and write (MM2S) channel operation. It can be configured to have either
15  * one channel or two channels. If configured as two channels, one is to
16  * transmit to the video device (MM2S) and another is to receive from the
17  * video device (S2MM). Initialization, status, interrupt and management
18  * registers are accessed through an AXI4-Lite slave interface.
19  *
20  * The AXI Direct Memory Access (AXI DMA) core is a soft Xilinx IP core that
21  * provides high-bandwidth one dimensional direct memory access between memory
22  * and AXI4-Stream target peripherals. It supports one receive and one
23  * transmit channel, both of them optional at synthesis time.
24  *
25  * The AXI CDMA, is a soft IP, which provides high-bandwidth Direct Memory
26  * Access (DMA) between a memory-mapped source address and a memory-mapped
27  * destination address.
28  *
29  * The AXI Multichannel Direct Memory Access (AXI MCDMA) core is a soft
30  * Xilinx IP that provides high-bandwidth direct memory access between
31  * memory and AXI4-Stream target peripherals. It provides scatter gather
32  * (SG) interface with multiple channels independent configuration support.
33  *
34  */
35 
36 #include <linux/bitops.h>
37 #include <linux/dmapool.h>
38 #include <linux/dma/xilinx_dma.h>
39 #include <linux/init.h>
40 #include <linux/interrupt.h>
41 #include <linux/io.h>
42 #include <linux/iopoll.h>
43 #include <linux/module.h>
44 #include <linux/of.h>
45 #include <linux/of_dma.h>
46 #include <linux/of_irq.h>
47 #include <linux/platform_device.h>
48 #include <linux/slab.h>
49 #include <linux/clk.h>
50 #include <linux/io-64-nonatomic-lo-hi.h>
51 
52 #include "../dmaengine.h"
53 
54 /* Register/Descriptor Offsets */
55 #define XILINX_DMA_MM2S_CTRL_OFFSET		0x0000
56 #define XILINX_DMA_S2MM_CTRL_OFFSET		0x0030
57 #define XILINX_VDMA_MM2S_DESC_OFFSET		0x0050
58 #define XILINX_VDMA_S2MM_DESC_OFFSET		0x00a0
59 
60 /* Control Registers */
61 #define XILINX_DMA_REG_DMACR			0x0000
62 #define XILINX_DMA_DMACR_DELAY_MAX		0xff
63 #define XILINX_DMA_DMACR_DELAY_SHIFT		24
64 #define XILINX_DMA_DMACR_FRAME_COUNT_MAX	0xff
65 #define XILINX_DMA_DMACR_FRAME_COUNT_SHIFT	16
66 #define XILINX_DMA_DMACR_ERR_IRQ		BIT(14)
67 #define XILINX_DMA_DMACR_DLY_CNT_IRQ		BIT(13)
68 #define XILINX_DMA_DMACR_FRM_CNT_IRQ		BIT(12)
69 #define XILINX_DMA_DMACR_MASTER_SHIFT		8
70 #define XILINX_DMA_DMACR_FSYNCSRC_SHIFT	5
71 #define XILINX_DMA_DMACR_FRAMECNT_EN		BIT(4)
72 #define XILINX_DMA_DMACR_GENLOCK_EN		BIT(3)
73 #define XILINX_DMA_DMACR_RESET			BIT(2)
74 #define XILINX_DMA_DMACR_CIRC_EN		BIT(1)
75 #define XILINX_DMA_DMACR_RUNSTOP		BIT(0)
76 #define XILINX_DMA_DMACR_FSYNCSRC_MASK		GENMASK(6, 5)
77 #define XILINX_DMA_DMACR_DELAY_MASK		GENMASK(31, 24)
78 #define XILINX_DMA_DMACR_FRAME_COUNT_MASK	GENMASK(23, 16)
79 #define XILINX_DMA_DMACR_MASTER_MASK		GENMASK(11, 8)
80 
81 #define XILINX_DMA_REG_DMASR			0x0004
82 #define XILINX_DMA_DMASR_EOL_LATE_ERR		BIT(15)
83 #define XILINX_DMA_DMASR_ERR_IRQ		BIT(14)
84 #define XILINX_DMA_DMASR_DLY_CNT_IRQ		BIT(13)
85 #define XILINX_DMA_DMASR_FRM_CNT_IRQ		BIT(12)
86 #define XILINX_DMA_DMASR_SOF_LATE_ERR		BIT(11)
87 #define XILINX_DMA_DMASR_SG_DEC_ERR		BIT(10)
88 #define XILINX_DMA_DMASR_SG_SLV_ERR		BIT(9)
89 #define XILINX_DMA_DMASR_EOF_EARLY_ERR		BIT(8)
90 #define XILINX_DMA_DMASR_SOF_EARLY_ERR		BIT(7)
91 #define XILINX_DMA_DMASR_DMA_DEC_ERR		BIT(6)
92 #define XILINX_DMA_DMASR_DMA_SLAVE_ERR		BIT(5)
93 #define XILINX_DMA_DMASR_DMA_INT_ERR		BIT(4)
94 #define XILINX_DMA_DMASR_SG_MASK		BIT(3)
95 #define XILINX_DMA_DMASR_IDLE			BIT(1)
96 #define XILINX_DMA_DMASR_HALTED		BIT(0)
97 #define XILINX_DMA_DMASR_DELAY_MASK		GENMASK(31, 24)
98 #define XILINX_DMA_DMASR_FRAME_COUNT_MASK	GENMASK(23, 16)
99 
100 #define XILINX_DMA_REG_CURDESC			0x0008
101 #define XILINX_DMA_REG_TAILDESC		0x0010
102 #define XILINX_DMA_REG_REG_INDEX		0x0014
103 #define XILINX_DMA_REG_FRMSTORE		0x0018
104 #define XILINX_DMA_REG_THRESHOLD		0x001c
105 #define XILINX_DMA_REG_FRMPTR_STS		0x0024
106 #define XILINX_DMA_REG_PARK_PTR		0x0028
107 #define XILINX_DMA_PARK_PTR_WR_REF_SHIFT	8
108 #define XILINX_DMA_PARK_PTR_WR_REF_MASK		GENMASK(12, 8)
109 #define XILINX_DMA_PARK_PTR_RD_REF_SHIFT	0
110 #define XILINX_DMA_PARK_PTR_RD_REF_MASK		GENMASK(4, 0)
111 #define XILINX_DMA_REG_VDMA_VERSION		0x002c
112 
113 /* Register Direct Mode Registers */
114 #define XILINX_DMA_REG_VSIZE			0x0000
115 #define XILINX_DMA_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		512
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  * @has_axistream_connected: AXI DMA connected to AXI Stream IP
497  */
498 struct xilinx_dma_device {
499 	void __iomem *regs;
500 	struct device *dev;
501 	struct dma_device common;
502 	struct xilinx_dma_chan *chan[XILINX_MCDMA_MAX_CHANS_PER_DEVICE];
503 	u32 flush_on_fsync;
504 	bool ext_addr;
505 	struct platform_device  *pdev;
506 	const struct xilinx_dma_config *dma_config;
507 	struct clk *axi_clk;
508 	struct clk *tx_clk;
509 	struct clk *txs_clk;
510 	struct clk *rx_clk;
511 	struct clk *rxs_clk;
512 	u32 s2mm_chan_id;
513 	u32 mm2s_chan_id;
514 	u32 max_buffer_len;
515 	bool has_axistream_connected;
516 };
517 
518 /* Macros */
519 #define to_xilinx_chan(chan) \
520 	container_of(chan, struct xilinx_dma_chan, common)
521 #define to_dma_tx_descriptor(tx) \
522 	container_of(tx, struct xilinx_dma_tx_descriptor, async_tx)
523 #define xilinx_dma_poll_timeout(chan, reg, val, cond, delay_us, timeout_us) \
524 	readl_poll_timeout_atomic(chan->xdev->regs + chan->ctrl_offset + reg, \
525 				  val, cond, delay_us, timeout_us)
526 
527 /* IO accessors */
528 static inline u32 dma_read(struct xilinx_dma_chan *chan, u32 reg)
529 {
530 	return ioread32(chan->xdev->regs + reg);
531 }
532 
533 static inline void dma_write(struct xilinx_dma_chan *chan, u32 reg, u32 value)
534 {
535 	iowrite32(value, chan->xdev->regs + reg);
536 }
537 
538 static inline void vdma_desc_write(struct xilinx_dma_chan *chan, u32 reg,
539 				   u32 value)
540 {
541 	dma_write(chan, chan->desc_offset + reg, value);
542 }
543 
544 static inline u32 dma_ctrl_read(struct xilinx_dma_chan *chan, u32 reg)
545 {
546 	return dma_read(chan, chan->ctrl_offset + reg);
547 }
548 
549 static inline void dma_ctrl_write(struct xilinx_dma_chan *chan, u32 reg,
550 				   u32 value)
551 {
552 	dma_write(chan, chan->ctrl_offset + reg, value);
553 }
554 
555 static inline void dma_ctrl_clr(struct xilinx_dma_chan *chan, u32 reg,
556 				 u32 clr)
557 {
558 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) & ~clr);
559 }
560 
561 static inline void dma_ctrl_set(struct xilinx_dma_chan *chan, u32 reg,
562 				 u32 set)
563 {
564 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) | set);
565 }
566 
567 /**
568  * vdma_desc_write_64 - 64-bit descriptor write
569  * @chan: Driver specific VDMA channel
570  * @reg: Register to write
571  * @value_lsb: lower address of the descriptor.
572  * @value_msb: upper address of the descriptor.
573  *
574  * Since vdma driver is trying to write to a register offset which is not a
575  * multiple of 64 bits(ex : 0x5c), we are writing as two separate 32 bits
576  * instead of a single 64 bit register write.
577  */
578 static inline void vdma_desc_write_64(struct xilinx_dma_chan *chan, u32 reg,
579 				      u32 value_lsb, u32 value_msb)
580 {
581 	/* Write the lsb 32 bits*/
582 	writel(value_lsb, chan->xdev->regs + chan->desc_offset + reg);
583 
584 	/* Write the msb 32 bits */
585 	writel(value_msb, chan->xdev->regs + chan->desc_offset + reg + 4);
586 }
587 
588 static inline void dma_writeq(struct xilinx_dma_chan *chan, u32 reg, u64 value)
589 {
590 	lo_hi_writeq(value, chan->xdev->regs + chan->ctrl_offset + reg);
591 }
592 
593 static inline void xilinx_write(struct xilinx_dma_chan *chan, u32 reg,
594 				dma_addr_t addr)
595 {
596 	if (chan->ext_addr)
597 		dma_writeq(chan, reg, addr);
598 	else
599 		dma_ctrl_write(chan, reg, addr);
600 }
601 
602 static inline void xilinx_axidma_buf(struct xilinx_dma_chan *chan,
603 				     struct xilinx_axidma_desc_hw *hw,
604 				     dma_addr_t buf_addr, size_t sg_used,
605 				     size_t period_len)
606 {
607 	if (chan->ext_addr) {
608 		hw->buf_addr = lower_32_bits(buf_addr + sg_used + period_len);
609 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used +
610 						 period_len);
611 	} else {
612 		hw->buf_addr = buf_addr + sg_used + period_len;
613 	}
614 }
615 
616 static inline void xilinx_aximcdma_buf(struct xilinx_dma_chan *chan,
617 				       struct xilinx_aximcdma_desc_hw *hw,
618 				       dma_addr_t buf_addr, size_t sg_used)
619 {
620 	if (chan->ext_addr) {
621 		hw->buf_addr = lower_32_bits(buf_addr + sg_used);
622 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used);
623 	} else {
624 		hw->buf_addr = buf_addr + sg_used;
625 	}
626 }
627 
628 /**
629  * xilinx_dma_get_metadata_ptr- Populate metadata pointer and payload length
630  * @tx: async transaction descriptor
631  * @payload_len: metadata payload length
632  * @max_len: metadata max length
633  * Return: The app field pointer.
634  */
635 static void *xilinx_dma_get_metadata_ptr(struct dma_async_tx_descriptor *tx,
636 					 size_t *payload_len, size_t *max_len)
637 {
638 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
639 	struct xilinx_axidma_tx_segment *seg;
640 
641 	*max_len = *payload_len = sizeof(u32) * XILINX_DMA_NUM_APP_WORDS;
642 	seg = list_first_entry(&desc->segments,
643 			       struct xilinx_axidma_tx_segment, node);
644 	return seg->hw.app;
645 }
646 
647 static struct dma_descriptor_metadata_ops xilinx_dma_metadata_ops = {
648 	.get_ptr = xilinx_dma_get_metadata_ptr,
649 };
650 
651 /* -----------------------------------------------------------------------------
652  * Descriptors and segments alloc and free
653  */
654 
655 /**
656  * xilinx_vdma_alloc_tx_segment - Allocate transaction segment
657  * @chan: Driver specific DMA channel
658  *
659  * Return: The allocated segment on success and NULL on failure.
660  */
661 static struct xilinx_vdma_tx_segment *
662 xilinx_vdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
663 {
664 	struct xilinx_vdma_tx_segment *segment;
665 	dma_addr_t phys;
666 
667 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
668 	if (!segment)
669 		return NULL;
670 
671 	segment->phys = phys;
672 
673 	return segment;
674 }
675 
676 /**
677  * xilinx_cdma_alloc_tx_segment - Allocate transaction segment
678  * @chan: Driver specific DMA channel
679  *
680  * Return: The allocated segment on success and NULL on failure.
681  */
682 static struct xilinx_cdma_tx_segment *
683 xilinx_cdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
684 {
685 	struct xilinx_cdma_tx_segment *segment;
686 	dma_addr_t phys;
687 
688 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
689 	if (!segment)
690 		return NULL;
691 
692 	segment->phys = phys;
693 
694 	return segment;
695 }
696 
697 /**
698  * xilinx_axidma_alloc_tx_segment - Allocate transaction segment
699  * @chan: Driver specific DMA channel
700  *
701  * Return: The allocated segment on success and NULL on failure.
702  */
703 static struct xilinx_axidma_tx_segment *
704 xilinx_axidma_alloc_tx_segment(struct xilinx_dma_chan *chan)
705 {
706 	struct xilinx_axidma_tx_segment *segment = NULL;
707 	unsigned long flags;
708 
709 	spin_lock_irqsave(&chan->lock, flags);
710 	if (!list_empty(&chan->free_seg_list)) {
711 		segment = list_first_entry(&chan->free_seg_list,
712 					   struct xilinx_axidma_tx_segment,
713 					   node);
714 		list_del(&segment->node);
715 	}
716 	spin_unlock_irqrestore(&chan->lock, flags);
717 
718 	if (!segment)
719 		dev_dbg(chan->dev, "Could not find free tx segment\n");
720 
721 	return segment;
722 }
723 
724 /**
725  * xilinx_aximcdma_alloc_tx_segment - Allocate transaction segment
726  * @chan: Driver specific DMA channel
727  *
728  * Return: The allocated segment on success and NULL on failure.
729  */
730 static struct xilinx_aximcdma_tx_segment *
731 xilinx_aximcdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
732 {
733 	struct xilinx_aximcdma_tx_segment *segment = NULL;
734 	unsigned long flags;
735 
736 	spin_lock_irqsave(&chan->lock, flags);
737 	if (!list_empty(&chan->free_seg_list)) {
738 		segment = list_first_entry(&chan->free_seg_list,
739 					   struct xilinx_aximcdma_tx_segment,
740 					   node);
741 		list_del(&segment->node);
742 	}
743 	spin_unlock_irqrestore(&chan->lock, flags);
744 
745 	return segment;
746 }
747 
748 static void xilinx_dma_clean_hw_desc(struct xilinx_axidma_desc_hw *hw)
749 {
750 	u32 next_desc = hw->next_desc;
751 	u32 next_desc_msb = hw->next_desc_msb;
752 
753 	memset(hw, 0, sizeof(struct xilinx_axidma_desc_hw));
754 
755 	hw->next_desc = next_desc;
756 	hw->next_desc_msb = next_desc_msb;
757 }
758 
759 static void xilinx_mcdma_clean_hw_desc(struct xilinx_aximcdma_desc_hw *hw)
760 {
761 	u32 next_desc = hw->next_desc;
762 	u32 next_desc_msb = hw->next_desc_msb;
763 
764 	memset(hw, 0, sizeof(struct xilinx_aximcdma_desc_hw));
765 
766 	hw->next_desc = next_desc;
767 	hw->next_desc_msb = next_desc_msb;
768 }
769 
770 /**
771  * xilinx_dma_free_tx_segment - Free transaction segment
772  * @chan: Driver specific DMA channel
773  * @segment: DMA transaction segment
774  */
775 static void xilinx_dma_free_tx_segment(struct xilinx_dma_chan *chan,
776 				struct xilinx_axidma_tx_segment *segment)
777 {
778 	xilinx_dma_clean_hw_desc(&segment->hw);
779 
780 	list_add_tail(&segment->node, &chan->free_seg_list);
781 }
782 
783 /**
784  * xilinx_mcdma_free_tx_segment - Free transaction segment
785  * @chan: Driver specific DMA channel
786  * @segment: DMA transaction segment
787  */
788 static void xilinx_mcdma_free_tx_segment(struct xilinx_dma_chan *chan,
789 					 struct xilinx_aximcdma_tx_segment *
790 					 segment)
791 {
792 	xilinx_mcdma_clean_hw_desc(&segment->hw);
793 
794 	list_add_tail(&segment->node, &chan->free_seg_list);
795 }
796 
797 /**
798  * xilinx_cdma_free_tx_segment - Free transaction segment
799  * @chan: Driver specific DMA channel
800  * @segment: DMA transaction segment
801  */
802 static void xilinx_cdma_free_tx_segment(struct xilinx_dma_chan *chan,
803 				struct xilinx_cdma_tx_segment *segment)
804 {
805 	dma_pool_free(chan->desc_pool, segment, segment->phys);
806 }
807 
808 /**
809  * xilinx_vdma_free_tx_segment - Free transaction segment
810  * @chan: Driver specific DMA channel
811  * @segment: DMA transaction segment
812  */
813 static void xilinx_vdma_free_tx_segment(struct xilinx_dma_chan *chan,
814 					struct xilinx_vdma_tx_segment *segment)
815 {
816 	dma_pool_free(chan->desc_pool, segment, segment->phys);
817 }
818 
819 /**
820  * xilinx_dma_alloc_tx_descriptor - Allocate transaction descriptor
821  * @chan: Driver specific DMA channel
822  *
823  * Return: The allocated descriptor on success and NULL on failure.
824  */
825 static struct xilinx_dma_tx_descriptor *
826 xilinx_dma_alloc_tx_descriptor(struct xilinx_dma_chan *chan)
827 {
828 	struct xilinx_dma_tx_descriptor *desc;
829 
830 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
831 	if (!desc)
832 		return NULL;
833 
834 	INIT_LIST_HEAD(&desc->segments);
835 
836 	return desc;
837 }
838 
839 /**
840  * xilinx_dma_free_tx_descriptor - Free transaction descriptor
841  * @chan: Driver specific DMA channel
842  * @desc: DMA transaction descriptor
843  */
844 static void
845 xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
846 			       struct xilinx_dma_tx_descriptor *desc)
847 {
848 	struct xilinx_vdma_tx_segment *segment, *next;
849 	struct xilinx_cdma_tx_segment *cdma_segment, *cdma_next;
850 	struct xilinx_axidma_tx_segment *axidma_segment, *axidma_next;
851 	struct xilinx_aximcdma_tx_segment *aximcdma_segment, *aximcdma_next;
852 
853 	if (!desc)
854 		return;
855 
856 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
857 		list_for_each_entry_safe(segment, next, &desc->segments, node) {
858 			list_del(&segment->node);
859 			xilinx_vdma_free_tx_segment(chan, segment);
860 		}
861 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
862 		list_for_each_entry_safe(cdma_segment, cdma_next,
863 					 &desc->segments, node) {
864 			list_del(&cdma_segment->node);
865 			xilinx_cdma_free_tx_segment(chan, cdma_segment);
866 		}
867 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
868 		list_for_each_entry_safe(axidma_segment, axidma_next,
869 					 &desc->segments, node) {
870 			list_del(&axidma_segment->node);
871 			xilinx_dma_free_tx_segment(chan, axidma_segment);
872 		}
873 	} else {
874 		list_for_each_entry_safe(aximcdma_segment, aximcdma_next,
875 					 &desc->segments, node) {
876 			list_del(&aximcdma_segment->node);
877 			xilinx_mcdma_free_tx_segment(chan, aximcdma_segment);
878 		}
879 	}
880 
881 	kfree(desc);
882 }
883 
884 /* Required functions */
885 
886 /**
887  * xilinx_dma_free_desc_list - Free descriptors list
888  * @chan: Driver specific DMA channel
889  * @list: List to parse and delete the descriptor
890  */
891 static void xilinx_dma_free_desc_list(struct xilinx_dma_chan *chan,
892 					struct list_head *list)
893 {
894 	struct xilinx_dma_tx_descriptor *desc, *next;
895 
896 	list_for_each_entry_safe(desc, next, list, node) {
897 		list_del(&desc->node);
898 		xilinx_dma_free_tx_descriptor(chan, desc);
899 	}
900 }
901 
902 /**
903  * xilinx_dma_free_descriptors - Free channel descriptors
904  * @chan: Driver specific DMA channel
905  */
906 static void xilinx_dma_free_descriptors(struct xilinx_dma_chan *chan)
907 {
908 	unsigned long flags;
909 
910 	spin_lock_irqsave(&chan->lock, flags);
911 
912 	xilinx_dma_free_desc_list(chan, &chan->pending_list);
913 	xilinx_dma_free_desc_list(chan, &chan->done_list);
914 	xilinx_dma_free_desc_list(chan, &chan->active_list);
915 
916 	spin_unlock_irqrestore(&chan->lock, flags);
917 }
918 
919 /**
920  * xilinx_dma_free_chan_resources - Free channel resources
921  * @dchan: DMA channel
922  */
923 static void xilinx_dma_free_chan_resources(struct dma_chan *dchan)
924 {
925 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
926 	unsigned long flags;
927 
928 	dev_dbg(chan->dev, "Free all channel resources.\n");
929 
930 	xilinx_dma_free_descriptors(chan);
931 
932 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
933 		spin_lock_irqsave(&chan->lock, flags);
934 		INIT_LIST_HEAD(&chan->free_seg_list);
935 		spin_unlock_irqrestore(&chan->lock, flags);
936 
937 		/* Free memory that is allocated for BD */
938 		dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
939 				  XILINX_DMA_NUM_DESCS, chan->seg_v,
940 				  chan->seg_p);
941 
942 		/* Free Memory that is allocated for cyclic DMA Mode */
943 		dma_free_coherent(chan->dev, sizeof(*chan->cyclic_seg_v),
944 				  chan->cyclic_seg_v, chan->cyclic_seg_p);
945 	}
946 
947 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
948 		spin_lock_irqsave(&chan->lock, flags);
949 		INIT_LIST_HEAD(&chan->free_seg_list);
950 		spin_unlock_irqrestore(&chan->lock, flags);
951 
952 		/* Free memory that is allocated for BD */
953 		dma_free_coherent(chan->dev, sizeof(*chan->seg_mv) *
954 				  XILINX_DMA_NUM_DESCS, chan->seg_mv,
955 				  chan->seg_p);
956 	}
957 
958 	if (chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA &&
959 	    chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA) {
960 		dma_pool_destroy(chan->desc_pool);
961 		chan->desc_pool = NULL;
962 	}
963 
964 }
965 
966 /**
967  * xilinx_dma_get_residue - Compute residue for a given descriptor
968  * @chan: Driver specific dma channel
969  * @desc: dma transaction descriptor
970  *
971  * Return: The number of residue bytes for the descriptor.
972  */
973 static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
974 				  struct xilinx_dma_tx_descriptor *desc)
975 {
976 	struct xilinx_cdma_tx_segment *cdma_seg;
977 	struct xilinx_axidma_tx_segment *axidma_seg;
978 	struct xilinx_aximcdma_tx_segment *aximcdma_seg;
979 	struct xilinx_cdma_desc_hw *cdma_hw;
980 	struct xilinx_axidma_desc_hw *axidma_hw;
981 	struct xilinx_aximcdma_desc_hw *aximcdma_hw;
982 	struct list_head *entry;
983 	u32 residue = 0;
984 
985 	list_for_each(entry, &desc->segments) {
986 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
987 			cdma_seg = list_entry(entry,
988 					      struct xilinx_cdma_tx_segment,
989 					      node);
990 			cdma_hw = &cdma_seg->hw;
991 			residue += (cdma_hw->control - cdma_hw->status) &
992 				   chan->xdev->max_buffer_len;
993 		} else if (chan->xdev->dma_config->dmatype ==
994 			   XDMA_TYPE_AXIDMA) {
995 			axidma_seg = list_entry(entry,
996 						struct xilinx_axidma_tx_segment,
997 						node);
998 			axidma_hw = &axidma_seg->hw;
999 			residue += (axidma_hw->control - axidma_hw->status) &
1000 				   chan->xdev->max_buffer_len;
1001 		} else {
1002 			aximcdma_seg =
1003 				list_entry(entry,
1004 					   struct xilinx_aximcdma_tx_segment,
1005 					   node);
1006 			aximcdma_hw = &aximcdma_seg->hw;
1007 			residue +=
1008 				(aximcdma_hw->control - aximcdma_hw->status) &
1009 				chan->xdev->max_buffer_len;
1010 		}
1011 	}
1012 
1013 	return residue;
1014 }
1015 
1016 /**
1017  * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
1018  * @chan: Driver specific dma channel
1019  * @desc: dma transaction descriptor
1020  * @flags: flags for spin lock
1021  */
1022 static void xilinx_dma_chan_handle_cyclic(struct xilinx_dma_chan *chan,
1023 					  struct xilinx_dma_tx_descriptor *desc,
1024 					  unsigned long *flags)
1025 {
1026 	struct dmaengine_desc_callback cb;
1027 
1028 	dmaengine_desc_get_callback(&desc->async_tx, &cb);
1029 	if (dmaengine_desc_callback_valid(&cb)) {
1030 		spin_unlock_irqrestore(&chan->lock, *flags);
1031 		dmaengine_desc_callback_invoke(&cb, NULL);
1032 		spin_lock_irqsave(&chan->lock, *flags);
1033 	}
1034 }
1035 
1036 /**
1037  * xilinx_dma_chan_desc_cleanup - Clean channel descriptors
1038  * @chan: Driver specific DMA channel
1039  */
1040 static void xilinx_dma_chan_desc_cleanup(struct xilinx_dma_chan *chan)
1041 {
1042 	struct xilinx_dma_tx_descriptor *desc, *next;
1043 	unsigned long flags;
1044 
1045 	spin_lock_irqsave(&chan->lock, flags);
1046 
1047 	list_for_each_entry_safe(desc, next, &chan->done_list, node) {
1048 		struct dmaengine_result result;
1049 
1050 		if (desc->cyclic) {
1051 			xilinx_dma_chan_handle_cyclic(chan, desc, &flags);
1052 			break;
1053 		}
1054 
1055 		/* Remove from the list of running transactions */
1056 		list_del(&desc->node);
1057 
1058 		if (unlikely(desc->err)) {
1059 			if (chan->direction == DMA_DEV_TO_MEM)
1060 				result.result = DMA_TRANS_READ_FAILED;
1061 			else
1062 				result.result = DMA_TRANS_WRITE_FAILED;
1063 		} else {
1064 			result.result = DMA_TRANS_NOERROR;
1065 		}
1066 
1067 		result.residue = desc->residue;
1068 
1069 		/* Run the link descriptor callback function */
1070 		spin_unlock_irqrestore(&chan->lock, flags);
1071 		dmaengine_desc_get_callback_invoke(&desc->async_tx, &result);
1072 		spin_lock_irqsave(&chan->lock, flags);
1073 
1074 		/* Run any dependencies, then free the descriptor */
1075 		dma_run_dependencies(&desc->async_tx);
1076 		xilinx_dma_free_tx_descriptor(chan, desc);
1077 
1078 		/*
1079 		 * While we ran a callback the user called a terminate function,
1080 		 * which takes care of cleaning up any remaining descriptors
1081 		 */
1082 		if (chan->terminating)
1083 			break;
1084 	}
1085 
1086 	spin_unlock_irqrestore(&chan->lock, flags);
1087 }
1088 
1089 /**
1090  * xilinx_dma_do_tasklet - Schedule completion tasklet
1091  * @t: Pointer to the Xilinx DMA channel structure
1092  */
1093 static void xilinx_dma_do_tasklet(struct tasklet_struct *t)
1094 {
1095 	struct xilinx_dma_chan *chan = from_tasklet(chan, t, tasklet);
1096 
1097 	xilinx_dma_chan_desc_cleanup(chan);
1098 }
1099 
1100 /**
1101  * xilinx_dma_alloc_chan_resources - Allocate channel resources
1102  * @dchan: DMA channel
1103  *
1104  * Return: '0' on success and failure value on error
1105  */
1106 static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
1107 {
1108 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1109 	int i;
1110 
1111 	/* Has this channel already been allocated? */
1112 	if (chan->desc_pool)
1113 		return 0;
1114 
1115 	/*
1116 	 * We need the descriptor to be aligned to 64bytes
1117 	 * for meeting Xilinx VDMA specification requirement.
1118 	 */
1119 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1120 		/* Allocate the buffer descriptors. */
1121 		chan->seg_v = dma_alloc_coherent(chan->dev,
1122 						 sizeof(*chan->seg_v) * XILINX_DMA_NUM_DESCS,
1123 						 &chan->seg_p, GFP_KERNEL);
1124 		if (!chan->seg_v) {
1125 			dev_err(chan->dev,
1126 				"unable to allocate channel %d descriptors\n",
1127 				chan->id);
1128 			return -ENOMEM;
1129 		}
1130 		/*
1131 		 * For cyclic DMA mode we need to program the tail Descriptor
1132 		 * register with a value which is not a part of the BD chain
1133 		 * so allocating a desc segment during channel allocation for
1134 		 * programming tail descriptor.
1135 		 */
1136 		chan->cyclic_seg_v = dma_alloc_coherent(chan->dev,
1137 							sizeof(*chan->cyclic_seg_v),
1138 							&chan->cyclic_seg_p,
1139 							GFP_KERNEL);
1140 		if (!chan->cyclic_seg_v) {
1141 			dev_err(chan->dev,
1142 				"unable to allocate desc segment for cyclic DMA\n");
1143 			dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
1144 				XILINX_DMA_NUM_DESCS, chan->seg_v,
1145 				chan->seg_p);
1146 			return -ENOMEM;
1147 		}
1148 		chan->cyclic_seg_v->phys = chan->cyclic_seg_p;
1149 
1150 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1151 			chan->seg_v[i].hw.next_desc =
1152 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1153 				((i + 1) % XILINX_DMA_NUM_DESCS));
1154 			chan->seg_v[i].hw.next_desc_msb =
1155 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1156 				((i + 1) % XILINX_DMA_NUM_DESCS));
1157 			chan->seg_v[i].phys = chan->seg_p +
1158 				sizeof(*chan->seg_v) * i;
1159 			list_add_tail(&chan->seg_v[i].node,
1160 				      &chan->free_seg_list);
1161 		}
1162 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
1163 		/* Allocate the buffer descriptors. */
1164 		chan->seg_mv = dma_alloc_coherent(chan->dev,
1165 						  sizeof(*chan->seg_mv) *
1166 						  XILINX_DMA_NUM_DESCS,
1167 						  &chan->seg_p, GFP_KERNEL);
1168 		if (!chan->seg_mv) {
1169 			dev_err(chan->dev,
1170 				"unable to allocate channel %d descriptors\n",
1171 				chan->id);
1172 			return -ENOMEM;
1173 		}
1174 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1175 			chan->seg_mv[i].hw.next_desc =
1176 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1177 				((i + 1) % XILINX_DMA_NUM_DESCS));
1178 			chan->seg_mv[i].hw.next_desc_msb =
1179 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1180 				((i + 1) % XILINX_DMA_NUM_DESCS));
1181 			chan->seg_mv[i].phys = chan->seg_p +
1182 				sizeof(*chan->seg_mv) * i;
1183 			list_add_tail(&chan->seg_mv[i].node,
1184 				      &chan->free_seg_list);
1185 		}
1186 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1187 		chan->desc_pool = dma_pool_create("xilinx_cdma_desc_pool",
1188 				   chan->dev,
1189 				   sizeof(struct xilinx_cdma_tx_segment),
1190 				   __alignof__(struct xilinx_cdma_tx_segment),
1191 				   0);
1192 	} else {
1193 		chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
1194 				     chan->dev,
1195 				     sizeof(struct xilinx_vdma_tx_segment),
1196 				     __alignof__(struct xilinx_vdma_tx_segment),
1197 				     0);
1198 	}
1199 
1200 	if (!chan->desc_pool &&
1201 	    ((chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA) &&
1202 		chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA)) {
1203 		dev_err(chan->dev,
1204 			"unable to allocate channel %d descriptor pool\n",
1205 			chan->id);
1206 		return -ENOMEM;
1207 	}
1208 
1209 	dma_cookie_init(dchan);
1210 
1211 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1212 		/* For AXI DMA resetting once channel will reset the
1213 		 * other channel as well so enable the interrupts here.
1214 		 */
1215 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1216 			      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1217 	}
1218 
1219 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
1220 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1221 			     XILINX_CDMA_CR_SGMODE);
1222 
1223 	return 0;
1224 }
1225 
1226 /**
1227  * xilinx_dma_calc_copysize - Calculate the amount of data to copy
1228  * @chan: Driver specific DMA channel
1229  * @size: Total data that needs to be copied
1230  * @done: Amount of data that has been already copied
1231  *
1232  * Return: Amount of data that has to be copied
1233  */
1234 static int xilinx_dma_calc_copysize(struct xilinx_dma_chan *chan,
1235 				    int size, int done)
1236 {
1237 	size_t copy;
1238 
1239 	copy = min_t(size_t, size - done,
1240 		     chan->xdev->max_buffer_len);
1241 
1242 	if ((copy + done < size) &&
1243 	    chan->xdev->common.copy_align) {
1244 		/*
1245 		 * If this is not the last descriptor, make sure
1246 		 * the next one will be properly aligned
1247 		 */
1248 		copy = rounddown(copy,
1249 				 (1 << chan->xdev->common.copy_align));
1250 	}
1251 	return copy;
1252 }
1253 
1254 /**
1255  * xilinx_dma_tx_status - Get DMA transaction status
1256  * @dchan: DMA channel
1257  * @cookie: Transaction identifier
1258  * @txstate: Transaction state
1259  *
1260  * Return: DMA transaction status
1261  */
1262 static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
1263 					dma_cookie_t cookie,
1264 					struct dma_tx_state *txstate)
1265 {
1266 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1267 	struct xilinx_dma_tx_descriptor *desc;
1268 	enum dma_status ret;
1269 	unsigned long flags;
1270 	u32 residue = 0;
1271 
1272 	ret = dma_cookie_status(dchan, cookie, txstate);
1273 	if (ret == DMA_COMPLETE || !txstate)
1274 		return ret;
1275 
1276 	spin_lock_irqsave(&chan->lock, flags);
1277 	if (!list_empty(&chan->active_list)) {
1278 		desc = list_last_entry(&chan->active_list,
1279 				       struct xilinx_dma_tx_descriptor, node);
1280 		/*
1281 		 * VDMA and simple mode do not support residue reporting, so the
1282 		 * residue field will always be 0.
1283 		 */
1284 		if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA)
1285 			residue = xilinx_dma_get_residue(chan, desc);
1286 	}
1287 	spin_unlock_irqrestore(&chan->lock, flags);
1288 
1289 	dma_set_residue(txstate, residue);
1290 
1291 	return ret;
1292 }
1293 
1294 /**
1295  * xilinx_dma_stop_transfer - Halt DMA channel
1296  * @chan: Driver specific DMA channel
1297  *
1298  * Return: '0' on success and failure value on error
1299  */
1300 static int xilinx_dma_stop_transfer(struct xilinx_dma_chan *chan)
1301 {
1302 	u32 val;
1303 
1304 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1305 
1306 	/* Wait for the hardware to halt */
1307 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1308 				       val & XILINX_DMA_DMASR_HALTED, 0,
1309 				       XILINX_DMA_LOOP_COUNT);
1310 }
1311 
1312 /**
1313  * xilinx_cdma_stop_transfer - Wait for the current transfer to complete
1314  * @chan: Driver specific DMA channel
1315  *
1316  * Return: '0' on success and failure value on error
1317  */
1318 static int xilinx_cdma_stop_transfer(struct xilinx_dma_chan *chan)
1319 {
1320 	u32 val;
1321 
1322 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1323 				       val & XILINX_DMA_DMASR_IDLE, 0,
1324 				       XILINX_DMA_LOOP_COUNT);
1325 }
1326 
1327 /**
1328  * xilinx_dma_start - Start DMA channel
1329  * @chan: Driver specific DMA channel
1330  */
1331 static void xilinx_dma_start(struct xilinx_dma_chan *chan)
1332 {
1333 	int err;
1334 	u32 val;
1335 
1336 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1337 
1338 	/* Wait for the hardware to start */
1339 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1340 				      !(val & XILINX_DMA_DMASR_HALTED), 0,
1341 				      XILINX_DMA_LOOP_COUNT);
1342 
1343 	if (err) {
1344 		dev_err(chan->dev, "Cannot start channel %p: %x\n",
1345 			chan, dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1346 
1347 		chan->err = true;
1348 	}
1349 }
1350 
1351 /**
1352  * xilinx_vdma_start_transfer - Starts VDMA transfer
1353  * @chan: Driver specific channel struct pointer
1354  */
1355 static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
1356 {
1357 	struct xilinx_vdma_config *config = &chan->config;
1358 	struct xilinx_dma_tx_descriptor *desc;
1359 	u32 reg, j;
1360 	struct xilinx_vdma_tx_segment *segment, *last = NULL;
1361 	int i = 0;
1362 
1363 	/* This function was invoked with lock held */
1364 	if (chan->err)
1365 		return;
1366 
1367 	if (!chan->idle)
1368 		return;
1369 
1370 	if (list_empty(&chan->pending_list))
1371 		return;
1372 
1373 	desc = list_first_entry(&chan->pending_list,
1374 				struct xilinx_dma_tx_descriptor, node);
1375 
1376 	/* Configure the hardware using info in the config structure */
1377 	if (chan->has_vflip) {
1378 		reg = dma_read(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP);
1379 		reg &= ~XILINX_VDMA_ENABLE_VERTICAL_FLIP;
1380 		reg |= config->vflip_en;
1381 		dma_write(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP,
1382 			  reg);
1383 	}
1384 
1385 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1386 
1387 	if (config->frm_cnt_en)
1388 		reg |= XILINX_DMA_DMACR_FRAMECNT_EN;
1389 	else
1390 		reg &= ~XILINX_DMA_DMACR_FRAMECNT_EN;
1391 
1392 	/* If not parking, enable circular mode */
1393 	if (config->park)
1394 		reg &= ~XILINX_DMA_DMACR_CIRC_EN;
1395 	else
1396 		reg |= XILINX_DMA_DMACR_CIRC_EN;
1397 
1398 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1399 
1400 	j = chan->desc_submitcount;
1401 	reg = dma_read(chan, XILINX_DMA_REG_PARK_PTR);
1402 	if (chan->direction == DMA_MEM_TO_DEV) {
1403 		reg &= ~XILINX_DMA_PARK_PTR_RD_REF_MASK;
1404 		reg |= j << XILINX_DMA_PARK_PTR_RD_REF_SHIFT;
1405 	} else {
1406 		reg &= ~XILINX_DMA_PARK_PTR_WR_REF_MASK;
1407 		reg |= j << XILINX_DMA_PARK_PTR_WR_REF_SHIFT;
1408 	}
1409 	dma_write(chan, XILINX_DMA_REG_PARK_PTR, reg);
1410 
1411 	/* Start the hardware */
1412 	xilinx_dma_start(chan);
1413 
1414 	if (chan->err)
1415 		return;
1416 
1417 	/* Start the transfer */
1418 	if (chan->desc_submitcount < chan->num_frms)
1419 		i = chan->desc_submitcount;
1420 
1421 	list_for_each_entry(segment, &desc->segments, node) {
1422 		if (chan->ext_addr)
1423 			vdma_desc_write_64(chan,
1424 				   XILINX_VDMA_REG_START_ADDRESS_64(i++),
1425 				   segment->hw.buf_addr,
1426 				   segment->hw.buf_addr_msb);
1427 		else
1428 			vdma_desc_write(chan,
1429 					XILINX_VDMA_REG_START_ADDRESS(i++),
1430 					segment->hw.buf_addr);
1431 
1432 		last = segment;
1433 	}
1434 
1435 	if (!last)
1436 		return;
1437 
1438 	/* HW expects these parameters to be same for one transaction */
1439 	vdma_desc_write(chan, XILINX_DMA_REG_HSIZE, last->hw.hsize);
1440 	vdma_desc_write(chan, XILINX_DMA_REG_FRMDLY_STRIDE,
1441 			last->hw.stride);
1442 	vdma_desc_write(chan, XILINX_DMA_REG_VSIZE, last->hw.vsize);
1443 
1444 	chan->desc_submitcount++;
1445 	chan->desc_pendingcount--;
1446 	list_move_tail(&desc->node, &chan->active_list);
1447 	if (chan->desc_submitcount == chan->num_frms)
1448 		chan->desc_submitcount = 0;
1449 
1450 	chan->idle = false;
1451 }
1452 
1453 /**
1454  * xilinx_cdma_start_transfer - Starts cdma transfer
1455  * @chan: Driver specific channel struct pointer
1456  */
1457 static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
1458 {
1459 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1460 	struct xilinx_cdma_tx_segment *tail_segment;
1461 	u32 ctrl_reg = dma_read(chan, XILINX_DMA_REG_DMACR);
1462 
1463 	if (chan->err)
1464 		return;
1465 
1466 	if (!chan->idle)
1467 		return;
1468 
1469 	if (list_empty(&chan->pending_list))
1470 		return;
1471 
1472 	head_desc = list_first_entry(&chan->pending_list,
1473 				     struct xilinx_dma_tx_descriptor, node);
1474 	tail_desc = list_last_entry(&chan->pending_list,
1475 				    struct xilinx_dma_tx_descriptor, node);
1476 	tail_segment = list_last_entry(&tail_desc->segments,
1477 				       struct xilinx_cdma_tx_segment, node);
1478 
1479 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1480 		ctrl_reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1481 		ctrl_reg |= chan->desc_pendingcount <<
1482 				XILINX_DMA_CR_COALESCE_SHIFT;
1483 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, ctrl_reg);
1484 	}
1485 
1486 	if (chan->has_sg) {
1487 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
1488 			     XILINX_CDMA_CR_SGMODE);
1489 
1490 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1491 			     XILINX_CDMA_CR_SGMODE);
1492 
1493 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1494 			     head_desc->async_tx.phys);
1495 
1496 		/* Update tail ptr register which will start the transfer */
1497 		xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1498 			     tail_segment->phys);
1499 	} else {
1500 		/* In simple mode */
1501 		struct xilinx_cdma_tx_segment *segment;
1502 		struct xilinx_cdma_desc_hw *hw;
1503 
1504 		segment = list_first_entry(&head_desc->segments,
1505 					   struct xilinx_cdma_tx_segment,
1506 					   node);
1507 
1508 		hw = &segment->hw;
1509 
1510 		xilinx_write(chan, XILINX_CDMA_REG_SRCADDR,
1511 			     xilinx_prep_dma_addr_t(hw->src_addr));
1512 		xilinx_write(chan, XILINX_CDMA_REG_DSTADDR,
1513 			     xilinx_prep_dma_addr_t(hw->dest_addr));
1514 
1515 		/* Start the transfer */
1516 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1517 				hw->control & chan->xdev->max_buffer_len);
1518 	}
1519 
1520 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1521 	chan->desc_pendingcount = 0;
1522 	chan->idle = false;
1523 }
1524 
1525 /**
1526  * xilinx_dma_start_transfer - Starts DMA transfer
1527  * @chan: Driver specific channel struct pointer
1528  */
1529 static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
1530 {
1531 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1532 	struct xilinx_axidma_tx_segment *tail_segment;
1533 	u32 reg;
1534 
1535 	if (chan->err)
1536 		return;
1537 
1538 	if (list_empty(&chan->pending_list))
1539 		return;
1540 
1541 	if (!chan->idle)
1542 		return;
1543 
1544 	head_desc = list_first_entry(&chan->pending_list,
1545 				     struct xilinx_dma_tx_descriptor, node);
1546 	tail_desc = list_last_entry(&chan->pending_list,
1547 				    struct xilinx_dma_tx_descriptor, node);
1548 	tail_segment = list_last_entry(&tail_desc->segments,
1549 				       struct xilinx_axidma_tx_segment, node);
1550 
1551 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1552 
1553 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1554 		reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1555 		reg |= chan->desc_pendingcount <<
1556 				  XILINX_DMA_CR_COALESCE_SHIFT;
1557 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1558 	}
1559 
1560 	if (chan->has_sg)
1561 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1562 			     head_desc->async_tx.phys);
1563 
1564 	xilinx_dma_start(chan);
1565 
1566 	if (chan->err)
1567 		return;
1568 
1569 	/* Start the transfer */
1570 	if (chan->has_sg) {
1571 		if (chan->cyclic)
1572 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1573 				     chan->cyclic_seg_v->phys);
1574 		else
1575 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1576 				     tail_segment->phys);
1577 	} else {
1578 		struct xilinx_axidma_tx_segment *segment;
1579 		struct xilinx_axidma_desc_hw *hw;
1580 
1581 		segment = list_first_entry(&head_desc->segments,
1582 					   struct xilinx_axidma_tx_segment,
1583 					   node);
1584 		hw = &segment->hw;
1585 
1586 		xilinx_write(chan, XILINX_DMA_REG_SRCDSTADDR,
1587 			     xilinx_prep_dma_addr_t(hw->buf_addr));
1588 
1589 		/* Start the transfer */
1590 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1591 			       hw->control & chan->xdev->max_buffer_len);
1592 	}
1593 
1594 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1595 	chan->desc_pendingcount = 0;
1596 	chan->idle = false;
1597 }
1598 
1599 /**
1600  * xilinx_mcdma_start_transfer - Starts MCDMA transfer
1601  * @chan: Driver specific channel struct pointer
1602  */
1603 static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan)
1604 {
1605 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1606 	struct xilinx_aximcdma_tx_segment *tail_segment;
1607 	u32 reg;
1608 
1609 	/*
1610 	 * lock has been held by calling functions, so we don't need it
1611 	 * to take it here again.
1612 	 */
1613 
1614 	if (chan->err)
1615 		return;
1616 
1617 	if (!chan->idle)
1618 		return;
1619 
1620 	if (list_empty(&chan->pending_list))
1621 		return;
1622 
1623 	head_desc = list_first_entry(&chan->pending_list,
1624 				     struct xilinx_dma_tx_descriptor, node);
1625 	tail_desc = list_last_entry(&chan->pending_list,
1626 				    struct xilinx_dma_tx_descriptor, node);
1627 	tail_segment = list_last_entry(&tail_desc->segments,
1628 				       struct xilinx_aximcdma_tx_segment, node);
1629 
1630 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1631 
1632 	if (chan->desc_pendingcount <= XILINX_MCDMA_COALESCE_MAX) {
1633 		reg &= ~XILINX_MCDMA_COALESCE_MASK;
1634 		reg |= chan->desc_pendingcount <<
1635 			XILINX_MCDMA_COALESCE_SHIFT;
1636 	}
1637 
1638 	reg |= XILINX_MCDMA_IRQ_ALL_MASK;
1639 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1640 
1641 	/* Program current descriptor */
1642 	xilinx_write(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET(chan->tdest),
1643 		     head_desc->async_tx.phys);
1644 
1645 	/* Program channel enable register */
1646 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHEN_OFFSET);
1647 	reg |= BIT(chan->tdest);
1648 	dma_ctrl_write(chan, XILINX_MCDMA_CHEN_OFFSET, reg);
1649 
1650 	/* Start the fetch of BDs for the channel */
1651 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1652 	reg |= XILINX_MCDMA_CR_RUNSTOP_MASK;
1653 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1654 
1655 	xilinx_dma_start(chan);
1656 
1657 	if (chan->err)
1658 		return;
1659 
1660 	/* Start the transfer */
1661 	xilinx_write(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET(chan->tdest),
1662 		     tail_segment->phys);
1663 
1664 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1665 	chan->desc_pendingcount = 0;
1666 	chan->idle = false;
1667 }
1668 
1669 /**
1670  * xilinx_dma_issue_pending - Issue pending transactions
1671  * @dchan: DMA channel
1672  */
1673 static void xilinx_dma_issue_pending(struct dma_chan *dchan)
1674 {
1675 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1676 	unsigned long flags;
1677 
1678 	spin_lock_irqsave(&chan->lock, flags);
1679 	chan->start_transfer(chan);
1680 	spin_unlock_irqrestore(&chan->lock, flags);
1681 }
1682 
1683 /**
1684  * xilinx_dma_device_config - Configure the DMA channel
1685  * @dchan: DMA channel
1686  * @config: channel configuration
1687  *
1688  * Return: 0 always.
1689  */
1690 static int xilinx_dma_device_config(struct dma_chan *dchan,
1691 				    struct dma_slave_config *config)
1692 {
1693 	return 0;
1694 }
1695 
1696 /**
1697  * xilinx_dma_complete_descriptor - Mark the active descriptor as complete
1698  * @chan : xilinx DMA channel
1699  *
1700  * CONTEXT: hardirq
1701  */
1702 static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
1703 {
1704 	struct xilinx_dma_tx_descriptor *desc, *next;
1705 
1706 	/* This function was invoked with lock held */
1707 	if (list_empty(&chan->active_list))
1708 		return;
1709 
1710 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
1711 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
1712 		    XDMA_TYPE_VDMA)
1713 			desc->residue = xilinx_dma_get_residue(chan, desc);
1714 		else
1715 			desc->residue = 0;
1716 		desc->err = chan->err;
1717 
1718 		list_del(&desc->node);
1719 		if (!desc->cyclic)
1720 			dma_cookie_complete(&desc->async_tx);
1721 		list_add_tail(&desc->node, &chan->done_list);
1722 	}
1723 }
1724 
1725 /**
1726  * xilinx_dma_reset - Reset DMA channel
1727  * @chan: Driver specific DMA channel
1728  *
1729  * Return: '0' on success and failure value on error
1730  */
1731 static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
1732 {
1733 	int err;
1734 	u32 tmp;
1735 
1736 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RESET);
1737 
1738 	/* Wait for the hardware to finish reset */
1739 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMACR, tmp,
1740 				      !(tmp & XILINX_DMA_DMACR_RESET), 0,
1741 				      XILINX_DMA_LOOP_COUNT);
1742 
1743 	if (err) {
1744 		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
1745 			dma_ctrl_read(chan, XILINX_DMA_REG_DMACR),
1746 			dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1747 		return -ETIMEDOUT;
1748 	}
1749 
1750 	chan->err = false;
1751 	chan->idle = true;
1752 	chan->desc_pendingcount = 0;
1753 	chan->desc_submitcount = 0;
1754 
1755 	return err;
1756 }
1757 
1758 /**
1759  * xilinx_dma_chan_reset - Reset DMA channel and enable interrupts
1760  * @chan: Driver specific DMA channel
1761  *
1762  * Return: '0' on success and failure value on error
1763  */
1764 static int xilinx_dma_chan_reset(struct xilinx_dma_chan *chan)
1765 {
1766 	int err;
1767 
1768 	/* Reset VDMA */
1769 	err = xilinx_dma_reset(chan);
1770 	if (err)
1771 		return err;
1772 
1773 	/* Enable interrupts */
1774 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1775 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1776 
1777 	return 0;
1778 }
1779 
1780 /**
1781  * xilinx_mcdma_irq_handler - MCDMA Interrupt handler
1782  * @irq: IRQ number
1783  * @data: Pointer to the Xilinx MCDMA channel structure
1784  *
1785  * Return: IRQ_HANDLED/IRQ_NONE
1786  */
1787 static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
1788 {
1789 	struct xilinx_dma_chan *chan = data;
1790 	u32 status, ser_offset, chan_sermask, chan_offset = 0, chan_id;
1791 
1792 	if (chan->direction == DMA_DEV_TO_MEM)
1793 		ser_offset = XILINX_MCDMA_RXINT_SER_OFFSET;
1794 	else
1795 		ser_offset = XILINX_MCDMA_TXINT_SER_OFFSET;
1796 
1797 	/* Read the channel id raising the interrupt*/
1798 	chan_sermask = dma_ctrl_read(chan, ser_offset);
1799 	chan_id = ffs(chan_sermask);
1800 
1801 	if (!chan_id)
1802 		return IRQ_NONE;
1803 
1804 	if (chan->direction == DMA_DEV_TO_MEM)
1805 		chan_offset = chan->xdev->dma_config->max_channels / 2;
1806 
1807 	chan_offset = chan_offset + (chan_id - 1);
1808 	chan = chan->xdev->chan[chan_offset];
1809 	/* Read the status and ack the interrupts. */
1810 	status = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest));
1811 	if (!(status & XILINX_MCDMA_IRQ_ALL_MASK))
1812 		return IRQ_NONE;
1813 
1814 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest),
1815 		       status & XILINX_MCDMA_IRQ_ALL_MASK);
1816 
1817 	if (status & XILINX_MCDMA_IRQ_ERR_MASK) {
1818 		dev_err(chan->dev, "Channel %p has errors %x cdr %x tdr %x\n",
1819 			chan,
1820 			dma_ctrl_read(chan, XILINX_MCDMA_CH_ERR_OFFSET),
1821 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET
1822 				      (chan->tdest)),
1823 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET
1824 				      (chan->tdest)));
1825 		chan->err = true;
1826 	}
1827 
1828 	if (status & XILINX_MCDMA_IRQ_DELAY_MASK) {
1829 		/*
1830 		 * Device takes too long to do the transfer when user requires
1831 		 * responsiveness.
1832 		 */
1833 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1834 	}
1835 
1836 	if (status & XILINX_MCDMA_IRQ_IOC_MASK) {
1837 		spin_lock(&chan->lock);
1838 		xilinx_dma_complete_descriptor(chan);
1839 		chan->idle = true;
1840 		chan->start_transfer(chan);
1841 		spin_unlock(&chan->lock);
1842 	}
1843 
1844 	tasklet_schedule(&chan->tasklet);
1845 	return IRQ_HANDLED;
1846 }
1847 
1848 /**
1849  * xilinx_dma_irq_handler - DMA Interrupt handler
1850  * @irq: IRQ number
1851  * @data: Pointer to the Xilinx DMA channel structure
1852  *
1853  * Return: IRQ_HANDLED/IRQ_NONE
1854  */
1855 static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
1856 {
1857 	struct xilinx_dma_chan *chan = data;
1858 	u32 status;
1859 
1860 	/* Read the status and ack the interrupts. */
1861 	status = dma_ctrl_read(chan, XILINX_DMA_REG_DMASR);
1862 	if (!(status & XILINX_DMA_DMAXR_ALL_IRQ_MASK))
1863 		return IRQ_NONE;
1864 
1865 	dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1866 			status & XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1867 
1868 	if (status & XILINX_DMA_DMASR_ERR_IRQ) {
1869 		/*
1870 		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
1871 		 * error is recoverable, ignore it. Otherwise flag the error.
1872 		 *
1873 		 * Only recoverable errors can be cleared in the DMASR register,
1874 		 * make sure not to write to other error bits to 1.
1875 		 */
1876 		u32 errors = status & XILINX_DMA_DMASR_ALL_ERR_MASK;
1877 
1878 		dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1879 				errors & XILINX_DMA_DMASR_ERR_RECOVER_MASK);
1880 
1881 		if (!chan->flush_on_fsync ||
1882 		    (errors & ~XILINX_DMA_DMASR_ERR_RECOVER_MASK)) {
1883 			dev_err(chan->dev,
1884 				"Channel %p has errors %x, cdr %x tdr %x\n",
1885 				chan, errors,
1886 				dma_ctrl_read(chan, XILINX_DMA_REG_CURDESC),
1887 				dma_ctrl_read(chan, XILINX_DMA_REG_TAILDESC));
1888 			chan->err = true;
1889 		}
1890 	}
1891 
1892 	if (status & XILINX_DMA_DMASR_DLY_CNT_IRQ) {
1893 		/*
1894 		 * Device takes too long to do the transfer when user requires
1895 		 * responsiveness.
1896 		 */
1897 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1898 	}
1899 
1900 	if (status & XILINX_DMA_DMASR_FRM_CNT_IRQ) {
1901 		spin_lock(&chan->lock);
1902 		xilinx_dma_complete_descriptor(chan);
1903 		chan->idle = true;
1904 		chan->start_transfer(chan);
1905 		spin_unlock(&chan->lock);
1906 	}
1907 
1908 	tasklet_schedule(&chan->tasklet);
1909 	return IRQ_HANDLED;
1910 }
1911 
1912 /**
1913  * append_desc_queue - Queuing descriptor
1914  * @chan: Driver specific dma channel
1915  * @desc: dma transaction descriptor
1916  */
1917 static void append_desc_queue(struct xilinx_dma_chan *chan,
1918 			      struct xilinx_dma_tx_descriptor *desc)
1919 {
1920 	struct xilinx_vdma_tx_segment *tail_segment;
1921 	struct xilinx_dma_tx_descriptor *tail_desc;
1922 	struct xilinx_axidma_tx_segment *axidma_tail_segment;
1923 	struct xilinx_aximcdma_tx_segment *aximcdma_tail_segment;
1924 	struct xilinx_cdma_tx_segment *cdma_tail_segment;
1925 
1926 	if (list_empty(&chan->pending_list))
1927 		goto append;
1928 
1929 	/*
1930 	 * Add the hardware descriptor to the chain of hardware descriptors
1931 	 * that already exists in memory.
1932 	 */
1933 	tail_desc = list_last_entry(&chan->pending_list,
1934 				    struct xilinx_dma_tx_descriptor, node);
1935 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
1936 		tail_segment = list_last_entry(&tail_desc->segments,
1937 					       struct xilinx_vdma_tx_segment,
1938 					       node);
1939 		tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1940 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1941 		cdma_tail_segment = list_last_entry(&tail_desc->segments,
1942 						struct xilinx_cdma_tx_segment,
1943 						node);
1944 		cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1945 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1946 		axidma_tail_segment = list_last_entry(&tail_desc->segments,
1947 					       struct xilinx_axidma_tx_segment,
1948 					       node);
1949 		axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1950 	} else {
1951 		aximcdma_tail_segment =
1952 			list_last_entry(&tail_desc->segments,
1953 					struct xilinx_aximcdma_tx_segment,
1954 					node);
1955 		aximcdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1956 	}
1957 
1958 	/*
1959 	 * Add the software descriptor and all children to the list
1960 	 * of pending transactions
1961 	 */
1962 append:
1963 	list_add_tail(&desc->node, &chan->pending_list);
1964 	chan->desc_pendingcount++;
1965 
1966 	if (chan->has_sg && (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA)
1967 	    && unlikely(chan->desc_pendingcount > chan->num_frms)) {
1968 		dev_dbg(chan->dev, "desc pendingcount is too high\n");
1969 		chan->desc_pendingcount = chan->num_frms;
1970 	}
1971 }
1972 
1973 /**
1974  * xilinx_dma_tx_submit - Submit DMA transaction
1975  * @tx: Async transaction descriptor
1976  *
1977  * Return: cookie value on success and failure value on error
1978  */
1979 static dma_cookie_t xilinx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
1980 {
1981 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
1982 	struct xilinx_dma_chan *chan = to_xilinx_chan(tx->chan);
1983 	dma_cookie_t cookie;
1984 	unsigned long flags;
1985 	int err;
1986 
1987 	if (chan->cyclic) {
1988 		xilinx_dma_free_tx_descriptor(chan, desc);
1989 		return -EBUSY;
1990 	}
1991 
1992 	if (chan->err) {
1993 		/*
1994 		 * If reset fails, need to hard reset the system.
1995 		 * Channel is no longer functional
1996 		 */
1997 		err = xilinx_dma_chan_reset(chan);
1998 		if (err < 0)
1999 			return err;
2000 	}
2001 
2002 	spin_lock_irqsave(&chan->lock, flags);
2003 
2004 	cookie = dma_cookie_assign(tx);
2005 
2006 	/* Put this transaction onto the tail of the pending queue */
2007 	append_desc_queue(chan, desc);
2008 
2009 	if (desc->cyclic)
2010 		chan->cyclic = true;
2011 
2012 	chan->terminating = false;
2013 
2014 	spin_unlock_irqrestore(&chan->lock, flags);
2015 
2016 	return cookie;
2017 }
2018 
2019 /**
2020  * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
2021  *	DMA_SLAVE transaction
2022  * @dchan: DMA channel
2023  * @xt: Interleaved template pointer
2024  * @flags: transfer ack flags
2025  *
2026  * Return: Async transaction descriptor on success and NULL on failure
2027  */
2028 static struct dma_async_tx_descriptor *
2029 xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
2030 				 struct dma_interleaved_template *xt,
2031 				 unsigned long flags)
2032 {
2033 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2034 	struct xilinx_dma_tx_descriptor *desc;
2035 	struct xilinx_vdma_tx_segment *segment;
2036 	struct xilinx_vdma_desc_hw *hw;
2037 
2038 	if (!is_slave_direction(xt->dir))
2039 		return NULL;
2040 
2041 	if (!xt->numf || !xt->sgl[0].size)
2042 		return NULL;
2043 
2044 	if (xt->frame_size != 1)
2045 		return NULL;
2046 
2047 	/* Allocate a transaction descriptor. */
2048 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2049 	if (!desc)
2050 		return NULL;
2051 
2052 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2053 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2054 	async_tx_ack(&desc->async_tx);
2055 
2056 	/* Allocate the link descriptor from DMA pool */
2057 	segment = xilinx_vdma_alloc_tx_segment(chan);
2058 	if (!segment)
2059 		goto error;
2060 
2061 	/* Fill in the hardware descriptor */
2062 	hw = &segment->hw;
2063 	hw->vsize = xt->numf;
2064 	hw->hsize = xt->sgl[0].size;
2065 	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
2066 			XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT;
2067 	hw->stride |= chan->config.frm_dly <<
2068 			XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
2069 
2070 	if (xt->dir != DMA_MEM_TO_DEV) {
2071 		if (chan->ext_addr) {
2072 			hw->buf_addr = lower_32_bits(xt->dst_start);
2073 			hw->buf_addr_msb = upper_32_bits(xt->dst_start);
2074 		} else {
2075 			hw->buf_addr = xt->dst_start;
2076 		}
2077 	} else {
2078 		if (chan->ext_addr) {
2079 			hw->buf_addr = lower_32_bits(xt->src_start);
2080 			hw->buf_addr_msb = upper_32_bits(xt->src_start);
2081 		} else {
2082 			hw->buf_addr = xt->src_start;
2083 		}
2084 	}
2085 
2086 	/* Insert the segment into the descriptor segments list. */
2087 	list_add_tail(&segment->node, &desc->segments);
2088 
2089 	/* Link the last hardware descriptor with the first. */
2090 	segment = list_first_entry(&desc->segments,
2091 				   struct xilinx_vdma_tx_segment, node);
2092 	desc->async_tx.phys = segment->phys;
2093 
2094 	return &desc->async_tx;
2095 
2096 error:
2097 	xilinx_dma_free_tx_descriptor(chan, desc);
2098 	return NULL;
2099 }
2100 
2101 /**
2102  * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
2103  * @dchan: DMA channel
2104  * @dma_dst: destination address
2105  * @dma_src: source address
2106  * @len: transfer length
2107  * @flags: transfer ack flags
2108  *
2109  * Return: Async transaction descriptor on success and NULL on failure
2110  */
2111 static struct dma_async_tx_descriptor *
2112 xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
2113 			dma_addr_t dma_src, size_t len, unsigned long flags)
2114 {
2115 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2116 	struct xilinx_dma_tx_descriptor *desc;
2117 	struct xilinx_cdma_tx_segment *segment;
2118 	struct xilinx_cdma_desc_hw *hw;
2119 
2120 	if (!len || len > chan->xdev->max_buffer_len)
2121 		return NULL;
2122 
2123 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2124 	if (!desc)
2125 		return NULL;
2126 
2127 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2128 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2129 
2130 	/* Allocate the link descriptor from DMA pool */
2131 	segment = xilinx_cdma_alloc_tx_segment(chan);
2132 	if (!segment)
2133 		goto error;
2134 
2135 	hw = &segment->hw;
2136 	hw->control = len;
2137 	hw->src_addr = dma_src;
2138 	hw->dest_addr = dma_dst;
2139 	if (chan->ext_addr) {
2140 		hw->src_addr_msb = upper_32_bits(dma_src);
2141 		hw->dest_addr_msb = upper_32_bits(dma_dst);
2142 	}
2143 
2144 	/* Insert the segment into the descriptor segments list. */
2145 	list_add_tail(&segment->node, &desc->segments);
2146 
2147 	desc->async_tx.phys = segment->phys;
2148 	hw->next_desc = segment->phys;
2149 
2150 	return &desc->async_tx;
2151 
2152 error:
2153 	xilinx_dma_free_tx_descriptor(chan, desc);
2154 	return NULL;
2155 }
2156 
2157 /**
2158  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2159  * @dchan: DMA channel
2160  * @sgl: scatterlist to transfer to/from
2161  * @sg_len: number of entries in @scatterlist
2162  * @direction: DMA direction
2163  * @flags: transfer ack flags
2164  * @context: APP words of the descriptor
2165  *
2166  * Return: Async transaction descriptor on success and NULL on failure
2167  */
2168 static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
2169 	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
2170 	enum dma_transfer_direction direction, unsigned long flags,
2171 	void *context)
2172 {
2173 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2174 	struct xilinx_dma_tx_descriptor *desc;
2175 	struct xilinx_axidma_tx_segment *segment = NULL;
2176 	u32 *app_w = (u32 *)context;
2177 	struct scatterlist *sg;
2178 	size_t copy;
2179 	size_t sg_used;
2180 	unsigned int i;
2181 
2182 	if (!is_slave_direction(direction))
2183 		return NULL;
2184 
2185 	/* Allocate a transaction descriptor. */
2186 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2187 	if (!desc)
2188 		return NULL;
2189 
2190 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2191 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2192 
2193 	/* Build transactions using information in the scatter gather list */
2194 	for_each_sg(sgl, sg, sg_len, i) {
2195 		sg_used = 0;
2196 
2197 		/* Loop until the entire scatterlist entry is used */
2198 		while (sg_used < sg_dma_len(sg)) {
2199 			struct xilinx_axidma_desc_hw *hw;
2200 
2201 			/* Get a free segment */
2202 			segment = xilinx_axidma_alloc_tx_segment(chan);
2203 			if (!segment)
2204 				goto error;
2205 
2206 			/*
2207 			 * Calculate the maximum number of bytes to transfer,
2208 			 * making sure it is less than the hw limit
2209 			 */
2210 			copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
2211 							sg_used);
2212 			hw = &segment->hw;
2213 
2214 			/* Fill in the descriptor */
2215 			xilinx_axidma_buf(chan, hw, sg_dma_address(sg),
2216 					  sg_used, 0);
2217 
2218 			hw->control = copy;
2219 
2220 			if (chan->direction == DMA_MEM_TO_DEV) {
2221 				if (app_w)
2222 					memcpy(hw->app, app_w, sizeof(u32) *
2223 					       XILINX_DMA_NUM_APP_WORDS);
2224 			}
2225 
2226 			sg_used += copy;
2227 
2228 			/*
2229 			 * Insert the segment into the descriptor segments
2230 			 * list.
2231 			 */
2232 			list_add_tail(&segment->node, &desc->segments);
2233 		}
2234 	}
2235 
2236 	segment = list_first_entry(&desc->segments,
2237 				   struct xilinx_axidma_tx_segment, node);
2238 	desc->async_tx.phys = segment->phys;
2239 
2240 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2241 	if (chan->direction == DMA_MEM_TO_DEV) {
2242 		segment->hw.control |= XILINX_DMA_BD_SOP;
2243 		segment = list_last_entry(&desc->segments,
2244 					  struct xilinx_axidma_tx_segment,
2245 					  node);
2246 		segment->hw.control |= XILINX_DMA_BD_EOP;
2247 	}
2248 
2249 	if (chan->xdev->has_axistream_connected)
2250 		desc->async_tx.metadata_ops = &xilinx_dma_metadata_ops;
2251 
2252 	return &desc->async_tx;
2253 
2254 error:
2255 	xilinx_dma_free_tx_descriptor(chan, desc);
2256 	return NULL;
2257 }
2258 
2259 /**
2260  * xilinx_dma_prep_dma_cyclic - prepare descriptors for a DMA_SLAVE transaction
2261  * @dchan: DMA channel
2262  * @buf_addr: Physical address of the buffer
2263  * @buf_len: Total length of the cyclic buffers
2264  * @period_len: length of individual cyclic buffer
2265  * @direction: DMA direction
2266  * @flags: transfer ack flags
2267  *
2268  * Return: Async transaction descriptor on success and NULL on failure
2269  */
2270 static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
2271 	struct dma_chan *dchan, dma_addr_t buf_addr, size_t buf_len,
2272 	size_t period_len, enum dma_transfer_direction direction,
2273 	unsigned long flags)
2274 {
2275 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2276 	struct xilinx_dma_tx_descriptor *desc;
2277 	struct xilinx_axidma_tx_segment *segment, *head_segment, *prev = NULL;
2278 	size_t copy, sg_used;
2279 	unsigned int num_periods;
2280 	int i;
2281 	u32 reg;
2282 
2283 	if (!period_len)
2284 		return NULL;
2285 
2286 	num_periods = buf_len / period_len;
2287 
2288 	if (!num_periods)
2289 		return NULL;
2290 
2291 	if (!is_slave_direction(direction))
2292 		return NULL;
2293 
2294 	/* Allocate a transaction descriptor. */
2295 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2296 	if (!desc)
2297 		return NULL;
2298 
2299 	chan->direction = direction;
2300 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2301 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2302 
2303 	for (i = 0; i < num_periods; ++i) {
2304 		sg_used = 0;
2305 
2306 		while (sg_used < period_len) {
2307 			struct xilinx_axidma_desc_hw *hw;
2308 
2309 			/* Get a free segment */
2310 			segment = xilinx_axidma_alloc_tx_segment(chan);
2311 			if (!segment)
2312 				goto error;
2313 
2314 			/*
2315 			 * Calculate the maximum number of bytes to transfer,
2316 			 * making sure it is less than the hw limit
2317 			 */
2318 			copy = xilinx_dma_calc_copysize(chan, period_len,
2319 							sg_used);
2320 			hw = &segment->hw;
2321 			xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
2322 					  period_len * i);
2323 			hw->control = copy;
2324 
2325 			if (prev)
2326 				prev->hw.next_desc = segment->phys;
2327 
2328 			prev = segment;
2329 			sg_used += copy;
2330 
2331 			/*
2332 			 * Insert the segment into the descriptor segments
2333 			 * list.
2334 			 */
2335 			list_add_tail(&segment->node, &desc->segments);
2336 		}
2337 	}
2338 
2339 	head_segment = list_first_entry(&desc->segments,
2340 				   struct xilinx_axidma_tx_segment, node);
2341 	desc->async_tx.phys = head_segment->phys;
2342 
2343 	desc->cyclic = true;
2344 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2345 	reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2346 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2347 
2348 	segment = list_last_entry(&desc->segments,
2349 				  struct xilinx_axidma_tx_segment,
2350 				  node);
2351 	segment->hw.next_desc = (u32) head_segment->phys;
2352 
2353 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2354 	if (direction == DMA_MEM_TO_DEV) {
2355 		head_segment->hw.control |= XILINX_DMA_BD_SOP;
2356 		segment->hw.control |= XILINX_DMA_BD_EOP;
2357 	}
2358 
2359 	return &desc->async_tx;
2360 
2361 error:
2362 	xilinx_dma_free_tx_descriptor(chan, desc);
2363 	return NULL;
2364 }
2365 
2366 /**
2367  * xilinx_mcdma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2368  * @dchan: DMA channel
2369  * @sgl: scatterlist to transfer to/from
2370  * @sg_len: number of entries in @scatterlist
2371  * @direction: DMA direction
2372  * @flags: transfer ack flags
2373  * @context: APP words of the descriptor
2374  *
2375  * Return: Async transaction descriptor on success and NULL on failure
2376  */
2377 static struct dma_async_tx_descriptor *
2378 xilinx_mcdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
2379 			   unsigned int sg_len,
2380 			   enum dma_transfer_direction direction,
2381 			   unsigned long flags, void *context)
2382 {
2383 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2384 	struct xilinx_dma_tx_descriptor *desc;
2385 	struct xilinx_aximcdma_tx_segment *segment = NULL;
2386 	u32 *app_w = (u32 *)context;
2387 	struct scatterlist *sg;
2388 	size_t copy;
2389 	size_t sg_used;
2390 	unsigned int i;
2391 
2392 	if (!is_slave_direction(direction))
2393 		return NULL;
2394 
2395 	/* Allocate a transaction descriptor. */
2396 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2397 	if (!desc)
2398 		return NULL;
2399 
2400 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2401 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2402 
2403 	/* Build transactions using information in the scatter gather list */
2404 	for_each_sg(sgl, sg, sg_len, i) {
2405 		sg_used = 0;
2406 
2407 		/* Loop until the entire scatterlist entry is used */
2408 		while (sg_used < sg_dma_len(sg)) {
2409 			struct xilinx_aximcdma_desc_hw *hw;
2410 
2411 			/* Get a free segment */
2412 			segment = xilinx_aximcdma_alloc_tx_segment(chan);
2413 			if (!segment)
2414 				goto error;
2415 
2416 			/*
2417 			 * Calculate the maximum number of bytes to transfer,
2418 			 * making sure it is less than the hw limit
2419 			 */
2420 			copy = min_t(size_t, sg_dma_len(sg) - sg_used,
2421 				     chan->xdev->max_buffer_len);
2422 			hw = &segment->hw;
2423 
2424 			/* Fill in the descriptor */
2425 			xilinx_aximcdma_buf(chan, hw, sg_dma_address(sg),
2426 					    sg_used);
2427 			hw->control = copy;
2428 
2429 			if (chan->direction == DMA_MEM_TO_DEV && app_w) {
2430 				memcpy(hw->app, app_w, sizeof(u32) *
2431 				       XILINX_DMA_NUM_APP_WORDS);
2432 			}
2433 
2434 			sg_used += copy;
2435 			/*
2436 			 * Insert the segment into the descriptor segments
2437 			 * list.
2438 			 */
2439 			list_add_tail(&segment->node, &desc->segments);
2440 		}
2441 	}
2442 
2443 	segment = list_first_entry(&desc->segments,
2444 				   struct xilinx_aximcdma_tx_segment, node);
2445 	desc->async_tx.phys = segment->phys;
2446 
2447 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2448 	if (chan->direction == DMA_MEM_TO_DEV) {
2449 		segment->hw.control |= XILINX_MCDMA_BD_SOP;
2450 		segment = list_last_entry(&desc->segments,
2451 					  struct xilinx_aximcdma_tx_segment,
2452 					  node);
2453 		segment->hw.control |= XILINX_MCDMA_BD_EOP;
2454 	}
2455 
2456 	return &desc->async_tx;
2457 
2458 error:
2459 	xilinx_dma_free_tx_descriptor(chan, desc);
2460 
2461 	return NULL;
2462 }
2463 
2464 /**
2465  * xilinx_dma_terminate_all - Halt the channel and free descriptors
2466  * @dchan: Driver specific DMA Channel pointer
2467  *
2468  * Return: '0' always.
2469  */
2470 static int xilinx_dma_terminate_all(struct dma_chan *dchan)
2471 {
2472 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2473 	u32 reg;
2474 	int err;
2475 
2476 	if (!chan->cyclic) {
2477 		err = chan->stop_transfer(chan);
2478 		if (err) {
2479 			dev_err(chan->dev, "Cannot stop channel %p: %x\n",
2480 				chan, dma_ctrl_read(chan,
2481 				XILINX_DMA_REG_DMASR));
2482 			chan->err = true;
2483 		}
2484 	}
2485 
2486 	xilinx_dma_chan_reset(chan);
2487 	/* Remove and free all of the descriptors in the lists */
2488 	chan->terminating = true;
2489 	xilinx_dma_free_descriptors(chan);
2490 	chan->idle = true;
2491 
2492 	if (chan->cyclic) {
2493 		reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2494 		reg &= ~XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2495 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2496 		chan->cyclic = false;
2497 	}
2498 
2499 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
2500 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2501 			     XILINX_CDMA_CR_SGMODE);
2502 
2503 	return 0;
2504 }
2505 
2506 static void xilinx_dma_synchronize(struct dma_chan *dchan)
2507 {
2508 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2509 
2510 	tasklet_kill(&chan->tasklet);
2511 }
2512 
2513 /**
2514  * xilinx_vdma_channel_set_config - Configure VDMA channel
2515  * Run-time configuration for Axi VDMA, supports:
2516  * . halt the channel
2517  * . configure interrupt coalescing and inter-packet delay threshold
2518  * . start/stop parking
2519  * . enable genlock
2520  *
2521  * @dchan: DMA channel
2522  * @cfg: VDMA device configuration pointer
2523  *
2524  * Return: '0' on success and failure value on error
2525  */
2526 int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
2527 					struct xilinx_vdma_config *cfg)
2528 {
2529 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2530 	u32 dmacr;
2531 
2532 	if (cfg->reset)
2533 		return xilinx_dma_chan_reset(chan);
2534 
2535 	dmacr = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2536 
2537 	chan->config.frm_dly = cfg->frm_dly;
2538 	chan->config.park = cfg->park;
2539 
2540 	/* genlock settings */
2541 	chan->config.gen_lock = cfg->gen_lock;
2542 	chan->config.master = cfg->master;
2543 
2544 	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
2545 	if (cfg->gen_lock && chan->genlock) {
2546 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
2547 		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
2548 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
2549 	}
2550 
2551 	chan->config.frm_cnt_en = cfg->frm_cnt_en;
2552 	chan->config.vflip_en = cfg->vflip_en;
2553 
2554 	if (cfg->park)
2555 		chan->config.park_frm = cfg->park_frm;
2556 	else
2557 		chan->config.park_frm = -1;
2558 
2559 	chan->config.coalesc = cfg->coalesc;
2560 	chan->config.delay = cfg->delay;
2561 
2562 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
2563 		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
2564 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
2565 		chan->config.coalesc = cfg->coalesc;
2566 	}
2567 
2568 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
2569 		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
2570 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
2571 		chan->config.delay = cfg->delay;
2572 	}
2573 
2574 	/* FSync Source selection */
2575 	dmacr &= ~XILINX_DMA_DMACR_FSYNCSRC_MASK;
2576 	dmacr |= cfg->ext_fsync << XILINX_DMA_DMACR_FSYNCSRC_SHIFT;
2577 
2578 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, dmacr);
2579 
2580 	return 0;
2581 }
2582 EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
2583 
2584 /* -----------------------------------------------------------------------------
2585  * Probe and remove
2586  */
2587 
2588 /**
2589  * xilinx_dma_chan_remove - Per Channel remove function
2590  * @chan: Driver specific DMA channel
2591  */
2592 static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
2593 {
2594 	/* Disable all interrupts */
2595 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2596 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
2597 
2598 	if (chan->irq > 0)
2599 		free_irq(chan->irq, chan);
2600 
2601 	tasklet_kill(&chan->tasklet);
2602 
2603 	list_del(&chan->common.device_node);
2604 }
2605 
2606 static int axidma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2607 			    struct clk **tx_clk, struct clk **rx_clk,
2608 			    struct clk **sg_clk, struct clk **tmp_clk)
2609 {
2610 	int err;
2611 
2612 	*tmp_clk = NULL;
2613 
2614 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2615 	if (IS_ERR(*axi_clk))
2616 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2617 
2618 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2619 	if (IS_ERR(*tx_clk))
2620 		*tx_clk = NULL;
2621 
2622 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2623 	if (IS_ERR(*rx_clk))
2624 		*rx_clk = NULL;
2625 
2626 	*sg_clk = devm_clk_get(&pdev->dev, "m_axi_sg_aclk");
2627 	if (IS_ERR(*sg_clk))
2628 		*sg_clk = NULL;
2629 
2630 	err = clk_prepare_enable(*axi_clk);
2631 	if (err) {
2632 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2633 		return err;
2634 	}
2635 
2636 	err = clk_prepare_enable(*tx_clk);
2637 	if (err) {
2638 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2639 		goto err_disable_axiclk;
2640 	}
2641 
2642 	err = clk_prepare_enable(*rx_clk);
2643 	if (err) {
2644 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2645 		goto err_disable_txclk;
2646 	}
2647 
2648 	err = clk_prepare_enable(*sg_clk);
2649 	if (err) {
2650 		dev_err(&pdev->dev, "failed to enable sg_clk (%d)\n", err);
2651 		goto err_disable_rxclk;
2652 	}
2653 
2654 	return 0;
2655 
2656 err_disable_rxclk:
2657 	clk_disable_unprepare(*rx_clk);
2658 err_disable_txclk:
2659 	clk_disable_unprepare(*tx_clk);
2660 err_disable_axiclk:
2661 	clk_disable_unprepare(*axi_clk);
2662 
2663 	return err;
2664 }
2665 
2666 static int axicdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2667 			    struct clk **dev_clk, struct clk **tmp_clk,
2668 			    struct clk **tmp1_clk, struct clk **tmp2_clk)
2669 {
2670 	int err;
2671 
2672 	*tmp_clk = NULL;
2673 	*tmp1_clk = NULL;
2674 	*tmp2_clk = NULL;
2675 
2676 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2677 	if (IS_ERR(*axi_clk))
2678 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2679 
2680 	*dev_clk = devm_clk_get(&pdev->dev, "m_axi_aclk");
2681 	if (IS_ERR(*dev_clk))
2682 		return dev_err_probe(&pdev->dev, PTR_ERR(*dev_clk), "failed to get dev_clk\n");
2683 
2684 	err = clk_prepare_enable(*axi_clk);
2685 	if (err) {
2686 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2687 		return err;
2688 	}
2689 
2690 	err = clk_prepare_enable(*dev_clk);
2691 	if (err) {
2692 		dev_err(&pdev->dev, "failed to enable dev_clk (%d)\n", err);
2693 		goto err_disable_axiclk;
2694 	}
2695 
2696 	return 0;
2697 
2698 err_disable_axiclk:
2699 	clk_disable_unprepare(*axi_clk);
2700 
2701 	return err;
2702 }
2703 
2704 static int axivdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2705 			    struct clk **tx_clk, struct clk **txs_clk,
2706 			    struct clk **rx_clk, struct clk **rxs_clk)
2707 {
2708 	int err;
2709 
2710 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2711 	if (IS_ERR(*axi_clk))
2712 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2713 
2714 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2715 	if (IS_ERR(*tx_clk))
2716 		*tx_clk = NULL;
2717 
2718 	*txs_clk = devm_clk_get(&pdev->dev, "m_axis_mm2s_aclk");
2719 	if (IS_ERR(*txs_clk))
2720 		*txs_clk = NULL;
2721 
2722 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2723 	if (IS_ERR(*rx_clk))
2724 		*rx_clk = NULL;
2725 
2726 	*rxs_clk = devm_clk_get(&pdev->dev, "s_axis_s2mm_aclk");
2727 	if (IS_ERR(*rxs_clk))
2728 		*rxs_clk = NULL;
2729 
2730 	err = clk_prepare_enable(*axi_clk);
2731 	if (err) {
2732 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n",
2733 			err);
2734 		return err;
2735 	}
2736 
2737 	err = clk_prepare_enable(*tx_clk);
2738 	if (err) {
2739 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2740 		goto err_disable_axiclk;
2741 	}
2742 
2743 	err = clk_prepare_enable(*txs_clk);
2744 	if (err) {
2745 		dev_err(&pdev->dev, "failed to enable txs_clk (%d)\n", err);
2746 		goto err_disable_txclk;
2747 	}
2748 
2749 	err = clk_prepare_enable(*rx_clk);
2750 	if (err) {
2751 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2752 		goto err_disable_txsclk;
2753 	}
2754 
2755 	err = clk_prepare_enable(*rxs_clk);
2756 	if (err) {
2757 		dev_err(&pdev->dev, "failed to enable rxs_clk (%d)\n", err);
2758 		goto err_disable_rxclk;
2759 	}
2760 
2761 	return 0;
2762 
2763 err_disable_rxclk:
2764 	clk_disable_unprepare(*rx_clk);
2765 err_disable_txsclk:
2766 	clk_disable_unprepare(*txs_clk);
2767 err_disable_txclk:
2768 	clk_disable_unprepare(*tx_clk);
2769 err_disable_axiclk:
2770 	clk_disable_unprepare(*axi_clk);
2771 
2772 	return err;
2773 }
2774 
2775 static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
2776 {
2777 	clk_disable_unprepare(xdev->rxs_clk);
2778 	clk_disable_unprepare(xdev->rx_clk);
2779 	clk_disable_unprepare(xdev->txs_clk);
2780 	clk_disable_unprepare(xdev->tx_clk);
2781 	clk_disable_unprepare(xdev->axi_clk);
2782 }
2783 
2784 /**
2785  * xilinx_dma_chan_probe - Per Channel Probing
2786  * It get channel features from the device tree entry and
2787  * initialize special channel handling routines
2788  *
2789  * @xdev: Driver specific device structure
2790  * @node: Device node
2791  *
2792  * Return: '0' on success and failure value on error
2793  */
2794 static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
2795 				  struct device_node *node)
2796 {
2797 	struct xilinx_dma_chan *chan;
2798 	bool has_dre = false;
2799 	u32 value, width;
2800 	int err;
2801 
2802 	/* Allocate and initialize the channel structure */
2803 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
2804 	if (!chan)
2805 		return -ENOMEM;
2806 
2807 	chan->dev = xdev->dev;
2808 	chan->xdev = xdev;
2809 	chan->desc_pendingcount = 0x0;
2810 	chan->ext_addr = xdev->ext_addr;
2811 	/* This variable ensures that descriptors are not
2812 	 * Submitted when dma engine is in progress. This variable is
2813 	 * Added to avoid polling for a bit in the status register to
2814 	 * Know dma state in the driver hot path.
2815 	 */
2816 	chan->idle = true;
2817 
2818 	spin_lock_init(&chan->lock);
2819 	INIT_LIST_HEAD(&chan->pending_list);
2820 	INIT_LIST_HEAD(&chan->done_list);
2821 	INIT_LIST_HEAD(&chan->active_list);
2822 	INIT_LIST_HEAD(&chan->free_seg_list);
2823 
2824 	/* Retrieve the channel properties from the device tree */
2825 	has_dre = of_property_read_bool(node, "xlnx,include-dre");
2826 
2827 	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
2828 
2829 	err = of_property_read_u32(node, "xlnx,datawidth", &value);
2830 	if (err) {
2831 		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
2832 		return err;
2833 	}
2834 	width = value >> 3; /* Convert bits to bytes */
2835 
2836 	/* If data width is greater than 8 bytes, DRE is not in hw */
2837 	if (width > 8)
2838 		has_dre = false;
2839 
2840 	if (!has_dre)
2841 		xdev->common.copy_align = (enum dmaengine_alignment)fls(width - 1);
2842 
2843 	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel") ||
2844 	    of_device_is_compatible(node, "xlnx,axi-dma-mm2s-channel") ||
2845 	    of_device_is_compatible(node, "xlnx,axi-cdma-channel")) {
2846 		chan->direction = DMA_MEM_TO_DEV;
2847 		chan->id = xdev->mm2s_chan_id++;
2848 		chan->tdest = chan->id;
2849 
2850 		chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
2851 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2852 			chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
2853 			chan->config.park = 1;
2854 
2855 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2856 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
2857 				chan->flush_on_fsync = true;
2858 		}
2859 	} else if (of_device_is_compatible(node,
2860 					   "xlnx,axi-vdma-s2mm-channel") ||
2861 		   of_device_is_compatible(node,
2862 					   "xlnx,axi-dma-s2mm-channel")) {
2863 		chan->direction = DMA_DEV_TO_MEM;
2864 		chan->id = xdev->s2mm_chan_id++;
2865 		chan->tdest = chan->id - xdev->dma_config->max_channels / 2;
2866 		chan->has_vflip = of_property_read_bool(node,
2867 					"xlnx,enable-vert-flip");
2868 		if (chan->has_vflip) {
2869 			chan->config.vflip_en = dma_read(chan,
2870 				XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP) &
2871 				XILINX_VDMA_ENABLE_VERTICAL_FLIP;
2872 		}
2873 
2874 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
2875 			chan->ctrl_offset = XILINX_MCDMA_S2MM_CTRL_OFFSET;
2876 		else
2877 			chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
2878 
2879 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2880 			chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
2881 			chan->config.park = 1;
2882 
2883 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2884 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
2885 				chan->flush_on_fsync = true;
2886 		}
2887 	} else {
2888 		dev_err(xdev->dev, "Invalid channel compatible node\n");
2889 		return -EINVAL;
2890 	}
2891 
2892 	/* Request the interrupt */
2893 	chan->irq = of_irq_get(node, chan->tdest);
2894 	if (chan->irq < 0)
2895 		return dev_err_probe(xdev->dev, chan->irq, "failed to get irq\n");
2896 	err = request_irq(chan->irq, xdev->dma_config->irq_handler,
2897 			  IRQF_SHARED, "xilinx-dma-controller", chan);
2898 	if (err) {
2899 		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
2900 		return err;
2901 	}
2902 
2903 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
2904 		chan->start_transfer = xilinx_dma_start_transfer;
2905 		chan->stop_transfer = xilinx_dma_stop_transfer;
2906 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
2907 		chan->start_transfer = xilinx_mcdma_start_transfer;
2908 		chan->stop_transfer = xilinx_dma_stop_transfer;
2909 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
2910 		chan->start_transfer = xilinx_cdma_start_transfer;
2911 		chan->stop_transfer = xilinx_cdma_stop_transfer;
2912 	} else {
2913 		chan->start_transfer = xilinx_vdma_start_transfer;
2914 		chan->stop_transfer = xilinx_dma_stop_transfer;
2915 	}
2916 
2917 	/* check if SG is enabled (only for AXIDMA, AXIMCDMA, and CDMA) */
2918 	if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) {
2919 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA ||
2920 		    dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) &
2921 			    XILINX_DMA_DMASR_SG_MASK)
2922 			chan->has_sg = true;
2923 		dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id,
2924 			chan->has_sg ? "enabled" : "disabled");
2925 	}
2926 
2927 	/* Initialize the tasklet */
2928 	tasklet_setup(&chan->tasklet, xilinx_dma_do_tasklet);
2929 
2930 	/*
2931 	 * Initialize the DMA channel and add it to the DMA engine channels
2932 	 * list.
2933 	 */
2934 	chan->common.device = &xdev->common;
2935 
2936 	list_add_tail(&chan->common.device_node, &xdev->common.channels);
2937 	xdev->chan[chan->id] = chan;
2938 
2939 	/* Reset the channel */
2940 	err = xilinx_dma_chan_reset(chan);
2941 	if (err < 0) {
2942 		dev_err(xdev->dev, "Reset channel failed\n");
2943 		return err;
2944 	}
2945 
2946 	return 0;
2947 }
2948 
2949 /**
2950  * xilinx_dma_child_probe - Per child node probe
2951  * It get number of dma-channels per child node from
2952  * device-tree and initializes all the channels.
2953  *
2954  * @xdev: Driver specific device structure
2955  * @node: Device node
2956  *
2957  * Return: '0' on success and failure value on error.
2958  */
2959 static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
2960 				    struct device_node *node)
2961 {
2962 	int ret, i;
2963 	u32 nr_channels = 1;
2964 
2965 	ret = of_property_read_u32(node, "dma-channels", &nr_channels);
2966 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA && ret < 0)
2967 		dev_warn(xdev->dev, "missing dma-channels property\n");
2968 
2969 	for (i = 0; i < nr_channels; i++) {
2970 		ret = xilinx_dma_chan_probe(xdev, node);
2971 		if (ret)
2972 			return ret;
2973 	}
2974 
2975 	return 0;
2976 }
2977 
2978 /**
2979  * of_dma_xilinx_xlate - Translation function
2980  * @dma_spec: Pointer to DMA specifier as found in the device tree
2981  * @ofdma: Pointer to DMA controller data
2982  *
2983  * Return: DMA channel pointer on success and NULL on error
2984  */
2985 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
2986 						struct of_dma *ofdma)
2987 {
2988 	struct xilinx_dma_device *xdev = ofdma->of_dma_data;
2989 	int chan_id = dma_spec->args[0];
2990 
2991 	if (chan_id >= xdev->dma_config->max_channels || !xdev->chan[chan_id])
2992 		return NULL;
2993 
2994 	return dma_get_slave_channel(&xdev->chan[chan_id]->common);
2995 }
2996 
2997 static const struct xilinx_dma_config axidma_config = {
2998 	.dmatype = XDMA_TYPE_AXIDMA,
2999 	.clk_init = axidma_clk_init,
3000 	.irq_handler = xilinx_dma_irq_handler,
3001 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3002 };
3003 
3004 static const struct xilinx_dma_config aximcdma_config = {
3005 	.dmatype = XDMA_TYPE_AXIMCDMA,
3006 	.clk_init = axidma_clk_init,
3007 	.irq_handler = xilinx_mcdma_irq_handler,
3008 	.max_channels = XILINX_MCDMA_MAX_CHANS_PER_DEVICE,
3009 };
3010 static const struct xilinx_dma_config axicdma_config = {
3011 	.dmatype = XDMA_TYPE_CDMA,
3012 	.clk_init = axicdma_clk_init,
3013 	.irq_handler = xilinx_dma_irq_handler,
3014 	.max_channels = XILINX_CDMA_MAX_CHANS_PER_DEVICE,
3015 };
3016 
3017 static const struct xilinx_dma_config axivdma_config = {
3018 	.dmatype = XDMA_TYPE_VDMA,
3019 	.clk_init = axivdma_clk_init,
3020 	.irq_handler = xilinx_dma_irq_handler,
3021 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3022 };
3023 
3024 static const struct of_device_id xilinx_dma_of_ids[] = {
3025 	{ .compatible = "xlnx,axi-dma-1.00.a", .data = &axidma_config },
3026 	{ .compatible = "xlnx,axi-cdma-1.00.a", .data = &axicdma_config },
3027 	{ .compatible = "xlnx,axi-vdma-1.00.a", .data = &axivdma_config },
3028 	{ .compatible = "xlnx,axi-mcdma-1.00.a", .data = &aximcdma_config },
3029 	{}
3030 };
3031 MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
3032 
3033 /**
3034  * xilinx_dma_probe - Driver probe function
3035  * @pdev: Pointer to the platform_device structure
3036  *
3037  * Return: '0' on success and failure value on error
3038  */
3039 static int xilinx_dma_probe(struct platform_device *pdev)
3040 {
3041 	int (*clk_init)(struct platform_device *, struct clk **, struct clk **,
3042 			struct clk **, struct clk **, struct clk **)
3043 					= axivdma_clk_init;
3044 	struct device_node *node = pdev->dev.of_node;
3045 	struct xilinx_dma_device *xdev;
3046 	struct device_node *child, *np = pdev->dev.of_node;
3047 	u32 num_frames, addr_width, len_width;
3048 	int i, err;
3049 
3050 	/* Allocate and initialize the DMA engine structure */
3051 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
3052 	if (!xdev)
3053 		return -ENOMEM;
3054 
3055 	xdev->dev = &pdev->dev;
3056 	if (np) {
3057 		const struct of_device_id *match;
3058 
3059 		match = of_match_node(xilinx_dma_of_ids, np);
3060 		if (match && match->data) {
3061 			xdev->dma_config = match->data;
3062 			clk_init = xdev->dma_config->clk_init;
3063 		}
3064 	}
3065 
3066 	err = clk_init(pdev, &xdev->axi_clk, &xdev->tx_clk, &xdev->txs_clk,
3067 		       &xdev->rx_clk, &xdev->rxs_clk);
3068 	if (err)
3069 		return err;
3070 
3071 	/* Request and map I/O memory */
3072 	xdev->regs = devm_platform_ioremap_resource(pdev, 0);
3073 	if (IS_ERR(xdev->regs)) {
3074 		err = PTR_ERR(xdev->regs);
3075 		goto disable_clks;
3076 	}
3077 	/* Retrieve the DMA engine properties from the device tree */
3078 	xdev->max_buffer_len = GENMASK(XILINX_DMA_MAX_TRANS_LEN_MAX - 1, 0);
3079 	xdev->s2mm_chan_id = xdev->dma_config->max_channels / 2;
3080 
3081 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA ||
3082 	    xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3083 		if (!of_property_read_u32(node, "xlnx,sg-length-width",
3084 					  &len_width)) {
3085 			if (len_width < XILINX_DMA_MAX_TRANS_LEN_MIN ||
3086 			    len_width > XILINX_DMA_V2_MAX_TRANS_LEN_MAX) {
3087 				dev_warn(xdev->dev,
3088 					 "invalid xlnx,sg-length-width property value. Using default width\n");
3089 			} else {
3090 				if (len_width > XILINX_DMA_MAX_TRANS_LEN_MAX)
3091 					dev_warn(xdev->dev, "Please ensure that IP supports buffer length > 23 bits\n");
3092 				xdev->max_buffer_len =
3093 					GENMASK(len_width - 1, 0);
3094 			}
3095 		}
3096 	}
3097 
3098 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3099 		xdev->has_axistream_connected =
3100 			of_property_read_bool(node, "xlnx,axistream-connected");
3101 	}
3102 
3103 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3104 		err = of_property_read_u32(node, "xlnx,num-fstores",
3105 					   &num_frames);
3106 		if (err < 0) {
3107 			dev_err(xdev->dev,
3108 				"missing xlnx,num-fstores property\n");
3109 			goto disable_clks;
3110 		}
3111 
3112 		err = of_property_read_u32(node, "xlnx,flush-fsync",
3113 					   &xdev->flush_on_fsync);
3114 		if (err < 0)
3115 			dev_warn(xdev->dev,
3116 				 "missing xlnx,flush-fsync property\n");
3117 	}
3118 
3119 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
3120 	if (err < 0)
3121 		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
3122 
3123 	if (addr_width > 32)
3124 		xdev->ext_addr = true;
3125 	else
3126 		xdev->ext_addr = false;
3127 
3128 	/* Set metadata mode */
3129 	if (xdev->has_axistream_connected)
3130 		xdev->common.desc_metadata_modes = DESC_METADATA_ENGINE;
3131 
3132 	/* Set the dma mask bits */
3133 	err = dma_set_mask_and_coherent(xdev->dev, DMA_BIT_MASK(addr_width));
3134 	if (err < 0) {
3135 		dev_err(xdev->dev, "DMA mask error %d\n", err);
3136 		goto disable_clks;
3137 	}
3138 
3139 	/* Initialize the DMA engine */
3140 	xdev->common.dev = &pdev->dev;
3141 
3142 	INIT_LIST_HEAD(&xdev->common.channels);
3143 	if (!(xdev->dma_config->dmatype == XDMA_TYPE_CDMA)) {
3144 		dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
3145 		dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
3146 	}
3147 
3148 	xdev->common.device_alloc_chan_resources =
3149 				xilinx_dma_alloc_chan_resources;
3150 	xdev->common.device_free_chan_resources =
3151 				xilinx_dma_free_chan_resources;
3152 	xdev->common.device_terminate_all = xilinx_dma_terminate_all;
3153 	xdev->common.device_synchronize = xilinx_dma_synchronize;
3154 	xdev->common.device_tx_status = xilinx_dma_tx_status;
3155 	xdev->common.device_issue_pending = xilinx_dma_issue_pending;
3156 	xdev->common.device_config = xilinx_dma_device_config;
3157 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3158 		dma_cap_set(DMA_CYCLIC, xdev->common.cap_mask);
3159 		xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
3160 		xdev->common.device_prep_dma_cyclic =
3161 					  xilinx_dma_prep_dma_cyclic;
3162 		/* Residue calculation is supported by only AXI DMA and CDMA */
3163 		xdev->common.residue_granularity =
3164 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3165 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
3166 		dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
3167 		xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
3168 		/* Residue calculation is supported by only AXI DMA and CDMA */
3169 		xdev->common.residue_granularity =
3170 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3171 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3172 		xdev->common.device_prep_slave_sg = xilinx_mcdma_prep_slave_sg;
3173 	} else {
3174 		xdev->common.device_prep_interleaved_dma =
3175 				xilinx_vdma_dma_prep_interleaved;
3176 	}
3177 
3178 	platform_set_drvdata(pdev, xdev);
3179 
3180 	/* Initialize the channels */
3181 	for_each_child_of_node(node, child) {
3182 		err = xilinx_dma_child_probe(xdev, child);
3183 		if (err < 0) {
3184 			of_node_put(child);
3185 			goto error;
3186 		}
3187 	}
3188 
3189 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3190 		for (i = 0; i < xdev->dma_config->max_channels; i++)
3191 			if (xdev->chan[i])
3192 				xdev->chan[i]->num_frms = num_frames;
3193 	}
3194 
3195 	/* Register the DMA engine with the core */
3196 	err = dma_async_device_register(&xdev->common);
3197 	if (err) {
3198 		dev_err(xdev->dev, "failed to register the dma device\n");
3199 		goto error;
3200 	}
3201 
3202 	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
3203 					 xdev);
3204 	if (err < 0) {
3205 		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
3206 		dma_async_device_unregister(&xdev->common);
3207 		goto error;
3208 	}
3209 
3210 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
3211 		dev_info(&pdev->dev, "Xilinx AXI DMA Engine Driver Probed!!\n");
3212 	else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA)
3213 		dev_info(&pdev->dev, "Xilinx AXI CDMA Engine Driver Probed!!\n");
3214 	else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
3215 		dev_info(&pdev->dev, "Xilinx AXI MCDMA Engine Driver Probed!!\n");
3216 	else
3217 		dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
3218 
3219 	return 0;
3220 
3221 error:
3222 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3223 		if (xdev->chan[i])
3224 			xilinx_dma_chan_remove(xdev->chan[i]);
3225 disable_clks:
3226 	xdma_disable_allclks(xdev);
3227 
3228 	return err;
3229 }
3230 
3231 /**
3232  * xilinx_dma_remove - Driver remove function
3233  * @pdev: Pointer to the platform_device structure
3234  *
3235  * Return: Always '0'
3236  */
3237 static int xilinx_dma_remove(struct platform_device *pdev)
3238 {
3239 	struct xilinx_dma_device *xdev = platform_get_drvdata(pdev);
3240 	int i;
3241 
3242 	of_dma_controller_free(pdev->dev.of_node);
3243 
3244 	dma_async_device_unregister(&xdev->common);
3245 
3246 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3247 		if (xdev->chan[i])
3248 			xilinx_dma_chan_remove(xdev->chan[i]);
3249 
3250 	xdma_disable_allclks(xdev);
3251 
3252 	return 0;
3253 }
3254 
3255 static struct platform_driver xilinx_vdma_driver = {
3256 	.driver = {
3257 		.name = "xilinx-vdma",
3258 		.of_match_table = xilinx_dma_of_ids,
3259 	},
3260 	.probe = xilinx_dma_probe,
3261 	.remove = xilinx_dma_remove,
3262 };
3263 
3264 module_platform_driver(xilinx_vdma_driver);
3265 
3266 MODULE_AUTHOR("Xilinx, Inc.");
3267 MODULE_DESCRIPTION("Xilinx VDMA driver");
3268 MODULE_LICENSE("GPL v2");
3269