xref: /openbmc/linux/drivers/dma/xilinx/xilinx_dma.c (revision c77d4c5081aa6508623be876afebff003a2e5875)
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_BD_COMP_MASK		BIT(31)
181 #define XILINX_DMA_COALESCE_MAX		255
182 #define XILINX_DMA_NUM_DESCS		512
183 #define XILINX_DMA_NUM_APP_WORDS	5
184 
185 /* AXI CDMA Specific Registers/Offsets */
186 #define XILINX_CDMA_REG_SRCADDR		0x18
187 #define XILINX_CDMA_REG_DSTADDR		0x20
188 
189 /* AXI CDMA Specific Masks */
190 #define XILINX_CDMA_CR_SGMODE          BIT(3)
191 
192 #define xilinx_prep_dma_addr_t(addr)	\
193 	((dma_addr_t)((u64)addr##_##msb << 32 | (addr)))
194 
195 /* AXI MCDMA Specific Registers/Offsets */
196 #define XILINX_MCDMA_MM2S_CTRL_OFFSET		0x0000
197 #define XILINX_MCDMA_S2MM_CTRL_OFFSET		0x0500
198 #define XILINX_MCDMA_CHEN_OFFSET		0x0008
199 #define XILINX_MCDMA_CH_ERR_OFFSET		0x0010
200 #define XILINX_MCDMA_RXINT_SER_OFFSET		0x0020
201 #define XILINX_MCDMA_TXINT_SER_OFFSET		0x0028
202 #define XILINX_MCDMA_CHAN_CR_OFFSET(x)		(0x40 + (x) * 0x40)
203 #define XILINX_MCDMA_CHAN_SR_OFFSET(x)		(0x44 + (x) * 0x40)
204 #define XILINX_MCDMA_CHAN_CDESC_OFFSET(x)	(0x48 + (x) * 0x40)
205 #define XILINX_MCDMA_CHAN_TDESC_OFFSET(x)	(0x50 + (x) * 0x40)
206 
207 /* AXI MCDMA Specific Masks/Shifts */
208 #define XILINX_MCDMA_COALESCE_SHIFT		16
209 #define XILINX_MCDMA_COALESCE_MAX		24
210 #define XILINX_MCDMA_IRQ_ALL_MASK		GENMASK(7, 5)
211 #define XILINX_MCDMA_COALESCE_MASK		GENMASK(23, 16)
212 #define XILINX_MCDMA_CR_RUNSTOP_MASK		BIT(0)
213 #define XILINX_MCDMA_IRQ_IOC_MASK		BIT(5)
214 #define XILINX_MCDMA_IRQ_DELAY_MASK		BIT(6)
215 #define XILINX_MCDMA_IRQ_ERR_MASK		BIT(7)
216 #define XILINX_MCDMA_BD_EOP			BIT(30)
217 #define XILINX_MCDMA_BD_SOP			BIT(31)
218 
219 /**
220  * struct xilinx_vdma_desc_hw - Hardware Descriptor
221  * @next_desc: Next Descriptor Pointer @0x00
222  * @pad1: Reserved @0x04
223  * @buf_addr: Buffer address @0x08
224  * @buf_addr_msb: MSB of Buffer address @0x0C
225  * @vsize: Vertical Size @0x10
226  * @hsize: Horizontal Size @0x14
227  * @stride: Number of bytes between the first
228  *	    pixels of each horizontal line @0x18
229  */
230 struct xilinx_vdma_desc_hw {
231 	u32 next_desc;
232 	u32 pad1;
233 	u32 buf_addr;
234 	u32 buf_addr_msb;
235 	u32 vsize;
236 	u32 hsize;
237 	u32 stride;
238 } __aligned(64);
239 
240 /**
241  * struct xilinx_axidma_desc_hw - Hardware Descriptor for AXI DMA
242  * @next_desc: Next Descriptor Pointer @0x00
243  * @next_desc_msb: MSB of Next Descriptor Pointer @0x04
244  * @buf_addr: Buffer address @0x08
245  * @buf_addr_msb: MSB of Buffer address @0x0C
246  * @reserved1: Reserved @0x10
247  * @reserved2: Reserved @0x14
248  * @control: Control field @0x18
249  * @status: Status field @0x1C
250  * @app: APP Fields @0x20 - 0x30
251  */
252 struct xilinx_axidma_desc_hw {
253 	u32 next_desc;
254 	u32 next_desc_msb;
255 	u32 buf_addr;
256 	u32 buf_addr_msb;
257 	u32 reserved1;
258 	u32 reserved2;
259 	u32 control;
260 	u32 status;
261 	u32 app[XILINX_DMA_NUM_APP_WORDS];
262 } __aligned(64);
263 
264 /**
265  * struct xilinx_aximcdma_desc_hw - Hardware Descriptor for AXI MCDMA
266  * @next_desc: Next Descriptor Pointer @0x00
267  * @next_desc_msb: MSB of Next Descriptor Pointer @0x04
268  * @buf_addr: Buffer address @0x08
269  * @buf_addr_msb: MSB of Buffer address @0x0C
270  * @rsvd: Reserved field @0x10
271  * @control: Control Information field @0x14
272  * @status: Status field @0x18
273  * @sideband_status: Status of sideband signals @0x1C
274  * @app: APP Fields @0x20 - 0x30
275  */
276 struct xilinx_aximcdma_desc_hw {
277 	u32 next_desc;
278 	u32 next_desc_msb;
279 	u32 buf_addr;
280 	u32 buf_addr_msb;
281 	u32 rsvd;
282 	u32 control;
283 	u32 status;
284 	u32 sideband_status;
285 	u32 app[XILINX_DMA_NUM_APP_WORDS];
286 } __aligned(64);
287 
288 /**
289  * struct xilinx_cdma_desc_hw - Hardware Descriptor
290  * @next_desc: Next Descriptor Pointer @0x00
291  * @next_desc_msb: Next Descriptor Pointer MSB @0x04
292  * @src_addr: Source address @0x08
293  * @src_addr_msb: Source address MSB @0x0C
294  * @dest_addr: Destination address @0x10
295  * @dest_addr_msb: Destination address MSB @0x14
296  * @control: Control field @0x18
297  * @status: Status field @0x1C
298  */
299 struct xilinx_cdma_desc_hw {
300 	u32 next_desc;
301 	u32 next_desc_msb;
302 	u32 src_addr;
303 	u32 src_addr_msb;
304 	u32 dest_addr;
305 	u32 dest_addr_msb;
306 	u32 control;
307 	u32 status;
308 } __aligned(64);
309 
310 /**
311  * struct xilinx_vdma_tx_segment - Descriptor segment
312  * @hw: Hardware descriptor
313  * @node: Node in the descriptor segments list
314  * @phys: Physical address of segment
315  */
316 struct xilinx_vdma_tx_segment {
317 	struct xilinx_vdma_desc_hw hw;
318 	struct list_head node;
319 	dma_addr_t phys;
320 } __aligned(64);
321 
322 /**
323  * struct xilinx_axidma_tx_segment - Descriptor segment
324  * @hw: Hardware descriptor
325  * @node: Node in the descriptor segments list
326  * @phys: Physical address of segment
327  */
328 struct xilinx_axidma_tx_segment {
329 	struct xilinx_axidma_desc_hw hw;
330 	struct list_head node;
331 	dma_addr_t phys;
332 } __aligned(64);
333 
334 /**
335  * struct xilinx_aximcdma_tx_segment - Descriptor segment
336  * @hw: Hardware descriptor
337  * @node: Node in the descriptor segments list
338  * @phys: Physical address of segment
339  */
340 struct xilinx_aximcdma_tx_segment {
341 	struct xilinx_aximcdma_desc_hw hw;
342 	struct list_head node;
343 	dma_addr_t phys;
344 } __aligned(64);
345 
346 /**
347  * struct xilinx_cdma_tx_segment - Descriptor segment
348  * @hw: Hardware descriptor
349  * @node: Node in the descriptor segments list
350  * @phys: Physical address of segment
351  */
352 struct xilinx_cdma_tx_segment {
353 	struct xilinx_cdma_desc_hw hw;
354 	struct list_head node;
355 	dma_addr_t phys;
356 } __aligned(64);
357 
358 /**
359  * struct xilinx_dma_tx_descriptor - Per Transaction structure
360  * @async_tx: Async transaction descriptor
361  * @segments: TX segments list
362  * @node: Node in the channel descriptors list
363  * @cyclic: Check for cyclic transfers.
364  * @err: Whether the descriptor has an error.
365  * @residue: Residue of the completed descriptor
366  */
367 struct xilinx_dma_tx_descriptor {
368 	struct dma_async_tx_descriptor async_tx;
369 	struct list_head segments;
370 	struct list_head node;
371 	bool cyclic;
372 	bool err;
373 	u32 residue;
374 };
375 
376 /**
377  * struct xilinx_dma_chan - Driver specific DMA channel structure
378  * @xdev: Driver specific device structure
379  * @ctrl_offset: Control registers offset
380  * @desc_offset: TX descriptor registers offset
381  * @lock: Descriptor operation lock
382  * @pending_list: Descriptors waiting
383  * @active_list: Descriptors ready to submit
384  * @done_list: Complete descriptors
385  * @free_seg_list: Free descriptors
386  * @common: DMA common channel
387  * @desc_pool: Descriptors pool
388  * @dev: The dma device
389  * @irq: Channel IRQ
390  * @id: Channel ID
391  * @direction: Transfer direction
392  * @num_frms: Number of frames
393  * @has_sg: Support scatter transfers
394  * @cyclic: Check for cyclic transfers.
395  * @genlock: Support genlock mode
396  * @err: Channel has errors
397  * @idle: Check for channel idle
398  * @terminating: Check for channel being synchronized by user
399  * @tasklet: Cleanup work after irq
400  * @config: Device configuration info
401  * @flush_on_fsync: Flush on Frame sync
402  * @desc_pendingcount: Descriptor pending count
403  * @ext_addr: Indicates 64 bit addressing is supported by dma channel
404  * @desc_submitcount: Descriptor h/w submitted count
405  * @seg_v: Statically allocated segments base
406  * @seg_mv: Statically allocated segments base for MCDMA
407  * @seg_p: Physical allocated segments base
408  * @cyclic_seg_v: Statically allocated segment base for cyclic transfers
409  * @cyclic_seg_p: Physical allocated segments base for cyclic dma
410  * @start_transfer: Differentiate b/w DMA IP's transfer
411  * @stop_transfer: Differentiate b/w DMA IP's quiesce
412  * @tdest: TDEST value for mcdma
413  * @has_vflip: S2MM vertical flip
414  */
415 struct xilinx_dma_chan {
416 	struct xilinx_dma_device *xdev;
417 	u32 ctrl_offset;
418 	u32 desc_offset;
419 	spinlock_t lock;
420 	struct list_head pending_list;
421 	struct list_head active_list;
422 	struct list_head done_list;
423 	struct list_head free_seg_list;
424 	struct dma_chan common;
425 	struct dma_pool *desc_pool;
426 	struct device *dev;
427 	int irq;
428 	int id;
429 	enum dma_transfer_direction direction;
430 	int num_frms;
431 	bool has_sg;
432 	bool cyclic;
433 	bool genlock;
434 	bool err;
435 	bool idle;
436 	bool terminating;
437 	struct tasklet_struct tasklet;
438 	struct xilinx_vdma_config config;
439 	bool flush_on_fsync;
440 	u32 desc_pendingcount;
441 	bool ext_addr;
442 	u32 desc_submitcount;
443 	struct xilinx_axidma_tx_segment *seg_v;
444 	struct xilinx_aximcdma_tx_segment *seg_mv;
445 	dma_addr_t seg_p;
446 	struct xilinx_axidma_tx_segment *cyclic_seg_v;
447 	dma_addr_t cyclic_seg_p;
448 	void (*start_transfer)(struct xilinx_dma_chan *chan);
449 	int (*stop_transfer)(struct xilinx_dma_chan *chan);
450 	u16 tdest;
451 	bool has_vflip;
452 };
453 
454 /**
455  * enum xdma_ip_type - DMA IP type.
456  *
457  * @XDMA_TYPE_AXIDMA: Axi dma ip.
458  * @XDMA_TYPE_CDMA: Axi cdma ip.
459  * @XDMA_TYPE_VDMA: Axi vdma ip.
460  * @XDMA_TYPE_AXIMCDMA: Axi MCDMA ip.
461  *
462  */
463 enum xdma_ip_type {
464 	XDMA_TYPE_AXIDMA = 0,
465 	XDMA_TYPE_CDMA,
466 	XDMA_TYPE_VDMA,
467 	XDMA_TYPE_AXIMCDMA
468 };
469 
470 struct xilinx_dma_config {
471 	enum xdma_ip_type dmatype;
472 	int (*clk_init)(struct platform_device *pdev, struct clk **axi_clk,
473 			struct clk **tx_clk, struct clk **txs_clk,
474 			struct clk **rx_clk, struct clk **rxs_clk);
475 	irqreturn_t (*irq_handler)(int irq, void *data);
476 	const int max_channels;
477 };
478 
479 /**
480  * struct xilinx_dma_device - DMA device structure
481  * @regs: I/O mapped base address
482  * @dev: Device Structure
483  * @common: DMA device structure
484  * @chan: Driver specific DMA channel
485  * @flush_on_fsync: Flush on frame sync
486  * @ext_addr: Indicates 64 bit addressing is supported by dma device
487  * @pdev: Platform device structure pointer
488  * @dma_config: DMA config structure
489  * @axi_clk: DMA Axi4-lite interace clock
490  * @tx_clk: DMA mm2s clock
491  * @txs_clk: DMA mm2s stream clock
492  * @rx_clk: DMA s2mm clock
493  * @rxs_clk: DMA s2mm stream clock
494  * @s2mm_chan_id: DMA s2mm channel identifier
495  * @mm2s_chan_id: DMA mm2s channel identifier
496  * @max_buffer_len: Max buffer length
497  * @has_axistream_connected: AXI DMA connected to AXI Stream IP
498  */
499 struct xilinx_dma_device {
500 	void __iomem *regs;
501 	struct device *dev;
502 	struct dma_device common;
503 	struct xilinx_dma_chan *chan[XILINX_MCDMA_MAX_CHANS_PER_DEVICE];
504 	u32 flush_on_fsync;
505 	bool ext_addr;
506 	struct platform_device  *pdev;
507 	const struct xilinx_dma_config *dma_config;
508 	struct clk *axi_clk;
509 	struct clk *tx_clk;
510 	struct clk *txs_clk;
511 	struct clk *rx_clk;
512 	struct clk *rxs_clk;
513 	u32 s2mm_chan_id;
514 	u32 mm2s_chan_id;
515 	u32 max_buffer_len;
516 	bool has_axistream_connected;
517 };
518 
519 /* Macros */
520 #define to_xilinx_chan(chan) \
521 	container_of(chan, struct xilinx_dma_chan, common)
522 #define to_dma_tx_descriptor(tx) \
523 	container_of(tx, struct xilinx_dma_tx_descriptor, async_tx)
524 #define xilinx_dma_poll_timeout(chan, reg, val, cond, delay_us, timeout_us) \
525 	readl_poll_timeout_atomic(chan->xdev->regs + chan->ctrl_offset + reg, \
526 				  val, cond, delay_us, timeout_us)
527 
528 /* IO accessors */
529 static inline u32 dma_read(struct xilinx_dma_chan *chan, u32 reg)
530 {
531 	return ioread32(chan->xdev->regs + reg);
532 }
533 
534 static inline void dma_write(struct xilinx_dma_chan *chan, u32 reg, u32 value)
535 {
536 	iowrite32(value, chan->xdev->regs + reg);
537 }
538 
539 static inline void vdma_desc_write(struct xilinx_dma_chan *chan, u32 reg,
540 				   u32 value)
541 {
542 	dma_write(chan, chan->desc_offset + reg, value);
543 }
544 
545 static inline u32 dma_ctrl_read(struct xilinx_dma_chan *chan, u32 reg)
546 {
547 	return dma_read(chan, chan->ctrl_offset + reg);
548 }
549 
550 static inline void dma_ctrl_write(struct xilinx_dma_chan *chan, u32 reg,
551 				   u32 value)
552 {
553 	dma_write(chan, chan->ctrl_offset + reg, value);
554 }
555 
556 static inline void dma_ctrl_clr(struct xilinx_dma_chan *chan, u32 reg,
557 				 u32 clr)
558 {
559 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) & ~clr);
560 }
561 
562 static inline void dma_ctrl_set(struct xilinx_dma_chan *chan, u32 reg,
563 				 u32 set)
564 {
565 	dma_ctrl_write(chan, reg, dma_ctrl_read(chan, reg) | set);
566 }
567 
568 /**
569  * vdma_desc_write_64 - 64-bit descriptor write
570  * @chan: Driver specific VDMA channel
571  * @reg: Register to write
572  * @value_lsb: lower address of the descriptor.
573  * @value_msb: upper address of the descriptor.
574  *
575  * Since vdma driver is trying to write to a register offset which is not a
576  * multiple of 64 bits(ex : 0x5c), we are writing as two separate 32 bits
577  * instead of a single 64 bit register write.
578  */
579 static inline void vdma_desc_write_64(struct xilinx_dma_chan *chan, u32 reg,
580 				      u32 value_lsb, u32 value_msb)
581 {
582 	/* Write the lsb 32 bits*/
583 	writel(value_lsb, chan->xdev->regs + chan->desc_offset + reg);
584 
585 	/* Write the msb 32 bits */
586 	writel(value_msb, chan->xdev->regs + chan->desc_offset + reg + 4);
587 }
588 
589 static inline void dma_writeq(struct xilinx_dma_chan *chan, u32 reg, u64 value)
590 {
591 	lo_hi_writeq(value, chan->xdev->regs + chan->ctrl_offset + reg);
592 }
593 
594 static inline void xilinx_write(struct xilinx_dma_chan *chan, u32 reg,
595 				dma_addr_t addr)
596 {
597 	if (chan->ext_addr)
598 		dma_writeq(chan, reg, addr);
599 	else
600 		dma_ctrl_write(chan, reg, addr);
601 }
602 
603 static inline void xilinx_axidma_buf(struct xilinx_dma_chan *chan,
604 				     struct xilinx_axidma_desc_hw *hw,
605 				     dma_addr_t buf_addr, size_t sg_used,
606 				     size_t period_len)
607 {
608 	if (chan->ext_addr) {
609 		hw->buf_addr = lower_32_bits(buf_addr + sg_used + period_len);
610 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used +
611 						 period_len);
612 	} else {
613 		hw->buf_addr = buf_addr + sg_used + period_len;
614 	}
615 }
616 
617 static inline void xilinx_aximcdma_buf(struct xilinx_dma_chan *chan,
618 				       struct xilinx_aximcdma_desc_hw *hw,
619 				       dma_addr_t buf_addr, size_t sg_used)
620 {
621 	if (chan->ext_addr) {
622 		hw->buf_addr = lower_32_bits(buf_addr + sg_used);
623 		hw->buf_addr_msb = upper_32_bits(buf_addr + sg_used);
624 	} else {
625 		hw->buf_addr = buf_addr + sg_used;
626 	}
627 }
628 
629 /**
630  * xilinx_dma_get_metadata_ptr- Populate metadata pointer and payload length
631  * @tx: async transaction descriptor
632  * @payload_len: metadata payload length
633  * @max_len: metadata max length
634  * Return: The app field pointer.
635  */
636 static void *xilinx_dma_get_metadata_ptr(struct dma_async_tx_descriptor *tx,
637 					 size_t *payload_len, size_t *max_len)
638 {
639 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
640 	struct xilinx_axidma_tx_segment *seg;
641 
642 	*max_len = *payload_len = sizeof(u32) * XILINX_DMA_NUM_APP_WORDS;
643 	seg = list_first_entry(&desc->segments,
644 			       struct xilinx_axidma_tx_segment, node);
645 	return seg->hw.app;
646 }
647 
648 static struct dma_descriptor_metadata_ops xilinx_dma_metadata_ops = {
649 	.get_ptr = xilinx_dma_get_metadata_ptr,
650 };
651 
652 /* -----------------------------------------------------------------------------
653  * Descriptors and segments alloc and free
654  */
655 
656 /**
657  * xilinx_vdma_alloc_tx_segment - Allocate transaction segment
658  * @chan: Driver specific DMA channel
659  *
660  * Return: The allocated segment on success and NULL on failure.
661  */
662 static struct xilinx_vdma_tx_segment *
663 xilinx_vdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
664 {
665 	struct xilinx_vdma_tx_segment *segment;
666 	dma_addr_t phys;
667 
668 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
669 	if (!segment)
670 		return NULL;
671 
672 	segment->phys = phys;
673 
674 	return segment;
675 }
676 
677 /**
678  * xilinx_cdma_alloc_tx_segment - Allocate transaction segment
679  * @chan: Driver specific DMA channel
680  *
681  * Return: The allocated segment on success and NULL on failure.
682  */
683 static struct xilinx_cdma_tx_segment *
684 xilinx_cdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
685 {
686 	struct xilinx_cdma_tx_segment *segment;
687 	dma_addr_t phys;
688 
689 	segment = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &phys);
690 	if (!segment)
691 		return NULL;
692 
693 	segment->phys = phys;
694 
695 	return segment;
696 }
697 
698 /**
699  * xilinx_axidma_alloc_tx_segment - Allocate transaction segment
700  * @chan: Driver specific DMA channel
701  *
702  * Return: The allocated segment on success and NULL on failure.
703  */
704 static struct xilinx_axidma_tx_segment *
705 xilinx_axidma_alloc_tx_segment(struct xilinx_dma_chan *chan)
706 {
707 	struct xilinx_axidma_tx_segment *segment = NULL;
708 	unsigned long flags;
709 
710 	spin_lock_irqsave(&chan->lock, flags);
711 	if (!list_empty(&chan->free_seg_list)) {
712 		segment = list_first_entry(&chan->free_seg_list,
713 					   struct xilinx_axidma_tx_segment,
714 					   node);
715 		list_del(&segment->node);
716 	}
717 	spin_unlock_irqrestore(&chan->lock, flags);
718 
719 	if (!segment)
720 		dev_dbg(chan->dev, "Could not find free tx segment\n");
721 
722 	return segment;
723 }
724 
725 /**
726  * xilinx_aximcdma_alloc_tx_segment - Allocate transaction segment
727  * @chan: Driver specific DMA channel
728  *
729  * Return: The allocated segment on success and NULL on failure.
730  */
731 static struct xilinx_aximcdma_tx_segment *
732 xilinx_aximcdma_alloc_tx_segment(struct xilinx_dma_chan *chan)
733 {
734 	struct xilinx_aximcdma_tx_segment *segment = NULL;
735 	unsigned long flags;
736 
737 	spin_lock_irqsave(&chan->lock, flags);
738 	if (!list_empty(&chan->free_seg_list)) {
739 		segment = list_first_entry(&chan->free_seg_list,
740 					   struct xilinx_aximcdma_tx_segment,
741 					   node);
742 		list_del(&segment->node);
743 	}
744 	spin_unlock_irqrestore(&chan->lock, flags);
745 
746 	return segment;
747 }
748 
749 static void xilinx_dma_clean_hw_desc(struct xilinx_axidma_desc_hw *hw)
750 {
751 	u32 next_desc = hw->next_desc;
752 	u32 next_desc_msb = hw->next_desc_msb;
753 
754 	memset(hw, 0, sizeof(struct xilinx_axidma_desc_hw));
755 
756 	hw->next_desc = next_desc;
757 	hw->next_desc_msb = next_desc_msb;
758 }
759 
760 static void xilinx_mcdma_clean_hw_desc(struct xilinx_aximcdma_desc_hw *hw)
761 {
762 	u32 next_desc = hw->next_desc;
763 	u32 next_desc_msb = hw->next_desc_msb;
764 
765 	memset(hw, 0, sizeof(struct xilinx_aximcdma_desc_hw));
766 
767 	hw->next_desc = next_desc;
768 	hw->next_desc_msb = next_desc_msb;
769 }
770 
771 /**
772  * xilinx_dma_free_tx_segment - Free transaction segment
773  * @chan: Driver specific DMA channel
774  * @segment: DMA transaction segment
775  */
776 static void xilinx_dma_free_tx_segment(struct xilinx_dma_chan *chan,
777 				struct xilinx_axidma_tx_segment *segment)
778 {
779 	xilinx_dma_clean_hw_desc(&segment->hw);
780 
781 	list_add_tail(&segment->node, &chan->free_seg_list);
782 }
783 
784 /**
785  * xilinx_mcdma_free_tx_segment - Free transaction segment
786  * @chan: Driver specific DMA channel
787  * @segment: DMA transaction segment
788  */
789 static void xilinx_mcdma_free_tx_segment(struct xilinx_dma_chan *chan,
790 					 struct xilinx_aximcdma_tx_segment *
791 					 segment)
792 {
793 	xilinx_mcdma_clean_hw_desc(&segment->hw);
794 
795 	list_add_tail(&segment->node, &chan->free_seg_list);
796 }
797 
798 /**
799  * xilinx_cdma_free_tx_segment - Free transaction segment
800  * @chan: Driver specific DMA channel
801  * @segment: DMA transaction segment
802  */
803 static void xilinx_cdma_free_tx_segment(struct xilinx_dma_chan *chan,
804 				struct xilinx_cdma_tx_segment *segment)
805 {
806 	dma_pool_free(chan->desc_pool, segment, segment->phys);
807 }
808 
809 /**
810  * xilinx_vdma_free_tx_segment - Free transaction segment
811  * @chan: Driver specific DMA channel
812  * @segment: DMA transaction segment
813  */
814 static void xilinx_vdma_free_tx_segment(struct xilinx_dma_chan *chan,
815 					struct xilinx_vdma_tx_segment *segment)
816 {
817 	dma_pool_free(chan->desc_pool, segment, segment->phys);
818 }
819 
820 /**
821  * xilinx_dma_alloc_tx_descriptor - Allocate transaction descriptor
822  * @chan: Driver specific DMA channel
823  *
824  * Return: The allocated descriptor on success and NULL on failure.
825  */
826 static struct xilinx_dma_tx_descriptor *
827 xilinx_dma_alloc_tx_descriptor(struct xilinx_dma_chan *chan)
828 {
829 	struct xilinx_dma_tx_descriptor *desc;
830 
831 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
832 	if (!desc)
833 		return NULL;
834 
835 	INIT_LIST_HEAD(&desc->segments);
836 
837 	return desc;
838 }
839 
840 /**
841  * xilinx_dma_free_tx_descriptor - Free transaction descriptor
842  * @chan: Driver specific DMA channel
843  * @desc: DMA transaction descriptor
844  */
845 static void
846 xilinx_dma_free_tx_descriptor(struct xilinx_dma_chan *chan,
847 			       struct xilinx_dma_tx_descriptor *desc)
848 {
849 	struct xilinx_vdma_tx_segment *segment, *next;
850 	struct xilinx_cdma_tx_segment *cdma_segment, *cdma_next;
851 	struct xilinx_axidma_tx_segment *axidma_segment, *axidma_next;
852 	struct xilinx_aximcdma_tx_segment *aximcdma_segment, *aximcdma_next;
853 
854 	if (!desc)
855 		return;
856 
857 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
858 		list_for_each_entry_safe(segment, next, &desc->segments, node) {
859 			list_del(&segment->node);
860 			xilinx_vdma_free_tx_segment(chan, segment);
861 		}
862 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
863 		list_for_each_entry_safe(cdma_segment, cdma_next,
864 					 &desc->segments, node) {
865 			list_del(&cdma_segment->node);
866 			xilinx_cdma_free_tx_segment(chan, cdma_segment);
867 		}
868 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
869 		list_for_each_entry_safe(axidma_segment, axidma_next,
870 					 &desc->segments, node) {
871 			list_del(&axidma_segment->node);
872 			xilinx_dma_free_tx_segment(chan, axidma_segment);
873 		}
874 	} else {
875 		list_for_each_entry_safe(aximcdma_segment, aximcdma_next,
876 					 &desc->segments, node) {
877 			list_del(&aximcdma_segment->node);
878 			xilinx_mcdma_free_tx_segment(chan, aximcdma_segment);
879 		}
880 	}
881 
882 	kfree(desc);
883 }
884 
885 /* Required functions */
886 
887 /**
888  * xilinx_dma_free_desc_list - Free descriptors list
889  * @chan: Driver specific DMA channel
890  * @list: List to parse and delete the descriptor
891  */
892 static void xilinx_dma_free_desc_list(struct xilinx_dma_chan *chan,
893 					struct list_head *list)
894 {
895 	struct xilinx_dma_tx_descriptor *desc, *next;
896 
897 	list_for_each_entry_safe(desc, next, list, node) {
898 		list_del(&desc->node);
899 		xilinx_dma_free_tx_descriptor(chan, desc);
900 	}
901 }
902 
903 /**
904  * xilinx_dma_free_descriptors - Free channel descriptors
905  * @chan: Driver specific DMA channel
906  */
907 static void xilinx_dma_free_descriptors(struct xilinx_dma_chan *chan)
908 {
909 	unsigned long flags;
910 
911 	spin_lock_irqsave(&chan->lock, flags);
912 
913 	xilinx_dma_free_desc_list(chan, &chan->pending_list);
914 	xilinx_dma_free_desc_list(chan, &chan->done_list);
915 	xilinx_dma_free_desc_list(chan, &chan->active_list);
916 
917 	spin_unlock_irqrestore(&chan->lock, flags);
918 }
919 
920 /**
921  * xilinx_dma_free_chan_resources - Free channel resources
922  * @dchan: DMA channel
923  */
924 static void xilinx_dma_free_chan_resources(struct dma_chan *dchan)
925 {
926 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
927 	unsigned long flags;
928 
929 	dev_dbg(chan->dev, "Free all channel resources.\n");
930 
931 	xilinx_dma_free_descriptors(chan);
932 
933 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
934 		spin_lock_irqsave(&chan->lock, flags);
935 		INIT_LIST_HEAD(&chan->free_seg_list);
936 		spin_unlock_irqrestore(&chan->lock, flags);
937 
938 		/* Free memory that is allocated for BD */
939 		dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
940 				  XILINX_DMA_NUM_DESCS, chan->seg_v,
941 				  chan->seg_p);
942 
943 		/* Free Memory that is allocated for cyclic DMA Mode */
944 		dma_free_coherent(chan->dev, sizeof(*chan->cyclic_seg_v),
945 				  chan->cyclic_seg_v, chan->cyclic_seg_p);
946 	}
947 
948 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
949 		spin_lock_irqsave(&chan->lock, flags);
950 		INIT_LIST_HEAD(&chan->free_seg_list);
951 		spin_unlock_irqrestore(&chan->lock, flags);
952 
953 		/* Free memory that is allocated for BD */
954 		dma_free_coherent(chan->dev, sizeof(*chan->seg_mv) *
955 				  XILINX_DMA_NUM_DESCS, chan->seg_mv,
956 				  chan->seg_p);
957 	}
958 
959 	if (chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA &&
960 	    chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA) {
961 		dma_pool_destroy(chan->desc_pool);
962 		chan->desc_pool = NULL;
963 	}
964 
965 }
966 
967 /**
968  * xilinx_dma_get_residue - Compute residue for a given descriptor
969  * @chan: Driver specific dma channel
970  * @desc: dma transaction descriptor
971  *
972  * Return: The number of residue bytes for the descriptor.
973  */
974 static u32 xilinx_dma_get_residue(struct xilinx_dma_chan *chan,
975 				  struct xilinx_dma_tx_descriptor *desc)
976 {
977 	struct xilinx_cdma_tx_segment *cdma_seg;
978 	struct xilinx_axidma_tx_segment *axidma_seg;
979 	struct xilinx_aximcdma_tx_segment *aximcdma_seg;
980 	struct xilinx_cdma_desc_hw *cdma_hw;
981 	struct xilinx_axidma_desc_hw *axidma_hw;
982 	struct xilinx_aximcdma_desc_hw *aximcdma_hw;
983 	struct list_head *entry;
984 	u32 residue = 0;
985 
986 	list_for_each(entry, &desc->segments) {
987 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
988 			cdma_seg = list_entry(entry,
989 					      struct xilinx_cdma_tx_segment,
990 					      node);
991 			cdma_hw = &cdma_seg->hw;
992 			residue += (cdma_hw->control - cdma_hw->status) &
993 				   chan->xdev->max_buffer_len;
994 		} else if (chan->xdev->dma_config->dmatype ==
995 			   XDMA_TYPE_AXIDMA) {
996 			axidma_seg = list_entry(entry,
997 						struct xilinx_axidma_tx_segment,
998 						node);
999 			axidma_hw = &axidma_seg->hw;
1000 			residue += (axidma_hw->control - axidma_hw->status) &
1001 				   chan->xdev->max_buffer_len;
1002 		} else {
1003 			aximcdma_seg =
1004 				list_entry(entry,
1005 					   struct xilinx_aximcdma_tx_segment,
1006 					   node);
1007 			aximcdma_hw = &aximcdma_seg->hw;
1008 			residue +=
1009 				(aximcdma_hw->control - aximcdma_hw->status) &
1010 				chan->xdev->max_buffer_len;
1011 		}
1012 	}
1013 
1014 	return residue;
1015 }
1016 
1017 /**
1018  * xilinx_dma_chan_handle_cyclic - Cyclic dma callback
1019  * @chan: Driver specific dma channel
1020  * @desc: dma transaction descriptor
1021  * @flags: flags for spin lock
1022  */
1023 static void xilinx_dma_chan_handle_cyclic(struct xilinx_dma_chan *chan,
1024 					  struct xilinx_dma_tx_descriptor *desc,
1025 					  unsigned long *flags)
1026 {
1027 	struct dmaengine_desc_callback cb;
1028 
1029 	dmaengine_desc_get_callback(&desc->async_tx, &cb);
1030 	if (dmaengine_desc_callback_valid(&cb)) {
1031 		spin_unlock_irqrestore(&chan->lock, *flags);
1032 		dmaengine_desc_callback_invoke(&cb, NULL);
1033 		spin_lock_irqsave(&chan->lock, *flags);
1034 	}
1035 }
1036 
1037 /**
1038  * xilinx_dma_chan_desc_cleanup - Clean channel descriptors
1039  * @chan: Driver specific DMA channel
1040  */
1041 static void xilinx_dma_chan_desc_cleanup(struct xilinx_dma_chan *chan)
1042 {
1043 	struct xilinx_dma_tx_descriptor *desc, *next;
1044 	unsigned long flags;
1045 
1046 	spin_lock_irqsave(&chan->lock, flags);
1047 
1048 	list_for_each_entry_safe(desc, next, &chan->done_list, node) {
1049 		struct dmaengine_result result;
1050 
1051 		if (desc->cyclic) {
1052 			xilinx_dma_chan_handle_cyclic(chan, desc, &flags);
1053 			break;
1054 		}
1055 
1056 		/* Remove from the list of running transactions */
1057 		list_del(&desc->node);
1058 
1059 		if (unlikely(desc->err)) {
1060 			if (chan->direction == DMA_DEV_TO_MEM)
1061 				result.result = DMA_TRANS_READ_FAILED;
1062 			else
1063 				result.result = DMA_TRANS_WRITE_FAILED;
1064 		} else {
1065 			result.result = DMA_TRANS_NOERROR;
1066 		}
1067 
1068 		result.residue = desc->residue;
1069 
1070 		/* Run the link descriptor callback function */
1071 		spin_unlock_irqrestore(&chan->lock, flags);
1072 		dmaengine_desc_get_callback_invoke(&desc->async_tx, &result);
1073 		spin_lock_irqsave(&chan->lock, flags);
1074 
1075 		/* Run any dependencies, then free the descriptor */
1076 		dma_run_dependencies(&desc->async_tx);
1077 		xilinx_dma_free_tx_descriptor(chan, desc);
1078 
1079 		/*
1080 		 * While we ran a callback the user called a terminate function,
1081 		 * which takes care of cleaning up any remaining descriptors
1082 		 */
1083 		if (chan->terminating)
1084 			break;
1085 	}
1086 
1087 	spin_unlock_irqrestore(&chan->lock, flags);
1088 }
1089 
1090 /**
1091  * xilinx_dma_do_tasklet - Schedule completion tasklet
1092  * @t: Pointer to the Xilinx DMA channel structure
1093  */
1094 static void xilinx_dma_do_tasklet(struct tasklet_struct *t)
1095 {
1096 	struct xilinx_dma_chan *chan = from_tasklet(chan, t, tasklet);
1097 
1098 	xilinx_dma_chan_desc_cleanup(chan);
1099 }
1100 
1101 /**
1102  * xilinx_dma_alloc_chan_resources - Allocate channel resources
1103  * @dchan: DMA channel
1104  *
1105  * Return: '0' on success and failure value on error
1106  */
1107 static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
1108 {
1109 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1110 	int i;
1111 
1112 	/* Has this channel already been allocated? */
1113 	if (chan->desc_pool)
1114 		return 0;
1115 
1116 	/*
1117 	 * We need the descriptor to be aligned to 64bytes
1118 	 * for meeting Xilinx VDMA specification requirement.
1119 	 */
1120 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1121 		/* Allocate the buffer descriptors. */
1122 		chan->seg_v = dma_alloc_coherent(chan->dev,
1123 						 sizeof(*chan->seg_v) * XILINX_DMA_NUM_DESCS,
1124 						 &chan->seg_p, GFP_KERNEL);
1125 		if (!chan->seg_v) {
1126 			dev_err(chan->dev,
1127 				"unable to allocate channel %d descriptors\n",
1128 				chan->id);
1129 			return -ENOMEM;
1130 		}
1131 		/*
1132 		 * For cyclic DMA mode we need to program the tail Descriptor
1133 		 * register with a value which is not a part of the BD chain
1134 		 * so allocating a desc segment during channel allocation for
1135 		 * programming tail descriptor.
1136 		 */
1137 		chan->cyclic_seg_v = dma_alloc_coherent(chan->dev,
1138 							sizeof(*chan->cyclic_seg_v),
1139 							&chan->cyclic_seg_p,
1140 							GFP_KERNEL);
1141 		if (!chan->cyclic_seg_v) {
1142 			dev_err(chan->dev,
1143 				"unable to allocate desc segment for cyclic DMA\n");
1144 			dma_free_coherent(chan->dev, sizeof(*chan->seg_v) *
1145 				XILINX_DMA_NUM_DESCS, chan->seg_v,
1146 				chan->seg_p);
1147 			return -ENOMEM;
1148 		}
1149 		chan->cyclic_seg_v->phys = chan->cyclic_seg_p;
1150 
1151 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1152 			chan->seg_v[i].hw.next_desc =
1153 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1154 				((i + 1) % XILINX_DMA_NUM_DESCS));
1155 			chan->seg_v[i].hw.next_desc_msb =
1156 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_v) *
1157 				((i + 1) % XILINX_DMA_NUM_DESCS));
1158 			chan->seg_v[i].phys = chan->seg_p +
1159 				sizeof(*chan->seg_v) * i;
1160 			list_add_tail(&chan->seg_v[i].node,
1161 				      &chan->free_seg_list);
1162 		}
1163 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
1164 		/* Allocate the buffer descriptors. */
1165 		chan->seg_mv = dma_alloc_coherent(chan->dev,
1166 						  sizeof(*chan->seg_mv) *
1167 						  XILINX_DMA_NUM_DESCS,
1168 						  &chan->seg_p, GFP_KERNEL);
1169 		if (!chan->seg_mv) {
1170 			dev_err(chan->dev,
1171 				"unable to allocate channel %d descriptors\n",
1172 				chan->id);
1173 			return -ENOMEM;
1174 		}
1175 		for (i = 0; i < XILINX_DMA_NUM_DESCS; i++) {
1176 			chan->seg_mv[i].hw.next_desc =
1177 			lower_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1178 				((i + 1) % XILINX_DMA_NUM_DESCS));
1179 			chan->seg_mv[i].hw.next_desc_msb =
1180 			upper_32_bits(chan->seg_p + sizeof(*chan->seg_mv) *
1181 				((i + 1) % XILINX_DMA_NUM_DESCS));
1182 			chan->seg_mv[i].phys = chan->seg_p +
1183 				sizeof(*chan->seg_mv) * i;
1184 			list_add_tail(&chan->seg_mv[i].node,
1185 				      &chan->free_seg_list);
1186 		}
1187 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1188 		chan->desc_pool = dma_pool_create("xilinx_cdma_desc_pool",
1189 				   chan->dev,
1190 				   sizeof(struct xilinx_cdma_tx_segment),
1191 				   __alignof__(struct xilinx_cdma_tx_segment),
1192 				   0);
1193 	} else {
1194 		chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool",
1195 				     chan->dev,
1196 				     sizeof(struct xilinx_vdma_tx_segment),
1197 				     __alignof__(struct xilinx_vdma_tx_segment),
1198 				     0);
1199 	}
1200 
1201 	if (!chan->desc_pool &&
1202 	    ((chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIDMA) &&
1203 		chan->xdev->dma_config->dmatype != XDMA_TYPE_AXIMCDMA)) {
1204 		dev_err(chan->dev,
1205 			"unable to allocate channel %d descriptor pool\n",
1206 			chan->id);
1207 		return -ENOMEM;
1208 	}
1209 
1210 	dma_cookie_init(dchan);
1211 
1212 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1213 		/* For AXI DMA resetting once channel will reset the
1214 		 * other channel as well so enable the interrupts here.
1215 		 */
1216 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1217 			      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1218 	}
1219 
1220 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
1221 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1222 			     XILINX_CDMA_CR_SGMODE);
1223 
1224 	return 0;
1225 }
1226 
1227 /**
1228  * xilinx_dma_calc_copysize - Calculate the amount of data to copy
1229  * @chan: Driver specific DMA channel
1230  * @size: Total data that needs to be copied
1231  * @done: Amount of data that has been already copied
1232  *
1233  * Return: Amount of data that has to be copied
1234  */
1235 static int xilinx_dma_calc_copysize(struct xilinx_dma_chan *chan,
1236 				    int size, int done)
1237 {
1238 	size_t copy;
1239 
1240 	copy = min_t(size_t, size - done,
1241 		     chan->xdev->max_buffer_len);
1242 
1243 	if ((copy + done < size) &&
1244 	    chan->xdev->common.copy_align) {
1245 		/*
1246 		 * If this is not the last descriptor, make sure
1247 		 * the next one will be properly aligned
1248 		 */
1249 		copy = rounddown(copy,
1250 				 (1 << chan->xdev->common.copy_align));
1251 	}
1252 	return copy;
1253 }
1254 
1255 /**
1256  * xilinx_dma_tx_status - Get DMA transaction status
1257  * @dchan: DMA channel
1258  * @cookie: Transaction identifier
1259  * @txstate: Transaction state
1260  *
1261  * Return: DMA transaction status
1262  */
1263 static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
1264 					dma_cookie_t cookie,
1265 					struct dma_tx_state *txstate)
1266 {
1267 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1268 	struct xilinx_dma_tx_descriptor *desc;
1269 	enum dma_status ret;
1270 	unsigned long flags;
1271 	u32 residue = 0;
1272 
1273 	ret = dma_cookie_status(dchan, cookie, txstate);
1274 	if (ret == DMA_COMPLETE || !txstate)
1275 		return ret;
1276 
1277 	spin_lock_irqsave(&chan->lock, flags);
1278 	if (!list_empty(&chan->active_list)) {
1279 		desc = list_last_entry(&chan->active_list,
1280 				       struct xilinx_dma_tx_descriptor, node);
1281 		/*
1282 		 * VDMA and simple mode do not support residue reporting, so the
1283 		 * residue field will always be 0.
1284 		 */
1285 		if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA)
1286 			residue = xilinx_dma_get_residue(chan, desc);
1287 	}
1288 	spin_unlock_irqrestore(&chan->lock, flags);
1289 
1290 	dma_set_residue(txstate, residue);
1291 
1292 	return ret;
1293 }
1294 
1295 /**
1296  * xilinx_dma_stop_transfer - Halt DMA channel
1297  * @chan: Driver specific DMA channel
1298  *
1299  * Return: '0' on success and failure value on error
1300  */
1301 static int xilinx_dma_stop_transfer(struct xilinx_dma_chan *chan)
1302 {
1303 	u32 val;
1304 
1305 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1306 
1307 	/* Wait for the hardware to halt */
1308 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1309 				       val & XILINX_DMA_DMASR_HALTED, 0,
1310 				       XILINX_DMA_LOOP_COUNT);
1311 }
1312 
1313 /**
1314  * xilinx_cdma_stop_transfer - Wait for the current transfer to complete
1315  * @chan: Driver specific DMA channel
1316  *
1317  * Return: '0' on success and failure value on error
1318  */
1319 static int xilinx_cdma_stop_transfer(struct xilinx_dma_chan *chan)
1320 {
1321 	u32 val;
1322 
1323 	return xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1324 				       val & XILINX_DMA_DMASR_IDLE, 0,
1325 				       XILINX_DMA_LOOP_COUNT);
1326 }
1327 
1328 /**
1329  * xilinx_dma_start - Start DMA channel
1330  * @chan: Driver specific DMA channel
1331  */
1332 static void xilinx_dma_start(struct xilinx_dma_chan *chan)
1333 {
1334 	int err;
1335 	u32 val;
1336 
1337 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RUNSTOP);
1338 
1339 	/* Wait for the hardware to start */
1340 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMASR, val,
1341 				      !(val & XILINX_DMA_DMASR_HALTED), 0,
1342 				      XILINX_DMA_LOOP_COUNT);
1343 
1344 	if (err) {
1345 		dev_err(chan->dev, "Cannot start channel %p: %x\n",
1346 			chan, dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1347 
1348 		chan->err = true;
1349 	}
1350 }
1351 
1352 /**
1353  * xilinx_vdma_start_transfer - Starts VDMA transfer
1354  * @chan: Driver specific channel struct pointer
1355  */
1356 static void xilinx_vdma_start_transfer(struct xilinx_dma_chan *chan)
1357 {
1358 	struct xilinx_vdma_config *config = &chan->config;
1359 	struct xilinx_dma_tx_descriptor *desc;
1360 	u32 reg, j;
1361 	struct xilinx_vdma_tx_segment *segment, *last = NULL;
1362 	int i = 0;
1363 
1364 	/* This function was invoked with lock held */
1365 	if (chan->err)
1366 		return;
1367 
1368 	if (!chan->idle)
1369 		return;
1370 
1371 	if (list_empty(&chan->pending_list))
1372 		return;
1373 
1374 	desc = list_first_entry(&chan->pending_list,
1375 				struct xilinx_dma_tx_descriptor, node);
1376 
1377 	/* Configure the hardware using info in the config structure */
1378 	if (chan->has_vflip) {
1379 		reg = dma_read(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP);
1380 		reg &= ~XILINX_VDMA_ENABLE_VERTICAL_FLIP;
1381 		reg |= config->vflip_en;
1382 		dma_write(chan, XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP,
1383 			  reg);
1384 	}
1385 
1386 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1387 
1388 	if (config->frm_cnt_en)
1389 		reg |= XILINX_DMA_DMACR_FRAMECNT_EN;
1390 	else
1391 		reg &= ~XILINX_DMA_DMACR_FRAMECNT_EN;
1392 
1393 	/* If not parking, enable circular mode */
1394 	if (config->park)
1395 		reg &= ~XILINX_DMA_DMACR_CIRC_EN;
1396 	else
1397 		reg |= XILINX_DMA_DMACR_CIRC_EN;
1398 
1399 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1400 
1401 	j = chan->desc_submitcount;
1402 	reg = dma_read(chan, XILINX_DMA_REG_PARK_PTR);
1403 	if (chan->direction == DMA_MEM_TO_DEV) {
1404 		reg &= ~XILINX_DMA_PARK_PTR_RD_REF_MASK;
1405 		reg |= j << XILINX_DMA_PARK_PTR_RD_REF_SHIFT;
1406 	} else {
1407 		reg &= ~XILINX_DMA_PARK_PTR_WR_REF_MASK;
1408 		reg |= j << XILINX_DMA_PARK_PTR_WR_REF_SHIFT;
1409 	}
1410 	dma_write(chan, XILINX_DMA_REG_PARK_PTR, reg);
1411 
1412 	/* Start the hardware */
1413 	xilinx_dma_start(chan);
1414 
1415 	if (chan->err)
1416 		return;
1417 
1418 	/* Start the transfer */
1419 	if (chan->desc_submitcount < chan->num_frms)
1420 		i = chan->desc_submitcount;
1421 
1422 	list_for_each_entry(segment, &desc->segments, node) {
1423 		if (chan->ext_addr)
1424 			vdma_desc_write_64(chan,
1425 				   XILINX_VDMA_REG_START_ADDRESS_64(i++),
1426 				   segment->hw.buf_addr,
1427 				   segment->hw.buf_addr_msb);
1428 		else
1429 			vdma_desc_write(chan,
1430 					XILINX_VDMA_REG_START_ADDRESS(i++),
1431 					segment->hw.buf_addr);
1432 
1433 		last = segment;
1434 	}
1435 
1436 	if (!last)
1437 		return;
1438 
1439 	/* HW expects these parameters to be same for one transaction */
1440 	vdma_desc_write(chan, XILINX_DMA_REG_HSIZE, last->hw.hsize);
1441 	vdma_desc_write(chan, XILINX_DMA_REG_FRMDLY_STRIDE,
1442 			last->hw.stride);
1443 	vdma_desc_write(chan, XILINX_DMA_REG_VSIZE, last->hw.vsize);
1444 
1445 	chan->desc_submitcount++;
1446 	chan->desc_pendingcount--;
1447 	list_move_tail(&desc->node, &chan->active_list);
1448 	if (chan->desc_submitcount == chan->num_frms)
1449 		chan->desc_submitcount = 0;
1450 
1451 	chan->idle = false;
1452 }
1453 
1454 /**
1455  * xilinx_cdma_start_transfer - Starts cdma transfer
1456  * @chan: Driver specific channel struct pointer
1457  */
1458 static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
1459 {
1460 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1461 	struct xilinx_cdma_tx_segment *tail_segment;
1462 	u32 ctrl_reg = dma_read(chan, XILINX_DMA_REG_DMACR);
1463 
1464 	if (chan->err)
1465 		return;
1466 
1467 	if (!chan->idle)
1468 		return;
1469 
1470 	if (list_empty(&chan->pending_list))
1471 		return;
1472 
1473 	head_desc = list_first_entry(&chan->pending_list,
1474 				     struct xilinx_dma_tx_descriptor, node);
1475 	tail_desc = list_last_entry(&chan->pending_list,
1476 				    struct xilinx_dma_tx_descriptor, node);
1477 	tail_segment = list_last_entry(&tail_desc->segments,
1478 				       struct xilinx_cdma_tx_segment, node);
1479 
1480 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1481 		ctrl_reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1482 		ctrl_reg |= chan->desc_pendingcount <<
1483 				XILINX_DMA_CR_COALESCE_SHIFT;
1484 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, ctrl_reg);
1485 	}
1486 
1487 	if (chan->has_sg) {
1488 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
1489 			     XILINX_CDMA_CR_SGMODE);
1490 
1491 		dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1492 			     XILINX_CDMA_CR_SGMODE);
1493 
1494 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1495 			     head_desc->async_tx.phys);
1496 
1497 		/* Update tail ptr register which will start the transfer */
1498 		xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1499 			     tail_segment->phys);
1500 	} else {
1501 		/* In simple mode */
1502 		struct xilinx_cdma_tx_segment *segment;
1503 		struct xilinx_cdma_desc_hw *hw;
1504 
1505 		segment = list_first_entry(&head_desc->segments,
1506 					   struct xilinx_cdma_tx_segment,
1507 					   node);
1508 
1509 		hw = &segment->hw;
1510 
1511 		xilinx_write(chan, XILINX_CDMA_REG_SRCADDR,
1512 			     xilinx_prep_dma_addr_t(hw->src_addr));
1513 		xilinx_write(chan, XILINX_CDMA_REG_DSTADDR,
1514 			     xilinx_prep_dma_addr_t(hw->dest_addr));
1515 
1516 		/* Start the transfer */
1517 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1518 				hw->control & chan->xdev->max_buffer_len);
1519 	}
1520 
1521 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1522 	chan->desc_pendingcount = 0;
1523 	chan->idle = false;
1524 }
1525 
1526 /**
1527  * xilinx_dma_start_transfer - Starts DMA transfer
1528  * @chan: Driver specific channel struct pointer
1529  */
1530 static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
1531 {
1532 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1533 	struct xilinx_axidma_tx_segment *tail_segment;
1534 	u32 reg;
1535 
1536 	if (chan->err)
1537 		return;
1538 
1539 	if (list_empty(&chan->pending_list))
1540 		return;
1541 
1542 	if (!chan->idle)
1543 		return;
1544 
1545 	head_desc = list_first_entry(&chan->pending_list,
1546 				     struct xilinx_dma_tx_descriptor, node);
1547 	tail_desc = list_last_entry(&chan->pending_list,
1548 				    struct xilinx_dma_tx_descriptor, node);
1549 	tail_segment = list_last_entry(&tail_desc->segments,
1550 				       struct xilinx_axidma_tx_segment, node);
1551 
1552 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
1553 
1554 	if (chan->desc_pendingcount <= XILINX_DMA_COALESCE_MAX) {
1555 		reg &= ~XILINX_DMA_CR_COALESCE_MAX;
1556 		reg |= chan->desc_pendingcount <<
1557 				  XILINX_DMA_CR_COALESCE_SHIFT;
1558 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
1559 	}
1560 
1561 	if (chan->has_sg)
1562 		xilinx_write(chan, XILINX_DMA_REG_CURDESC,
1563 			     head_desc->async_tx.phys);
1564 
1565 	xilinx_dma_start(chan);
1566 
1567 	if (chan->err)
1568 		return;
1569 
1570 	/* Start the transfer */
1571 	if (chan->has_sg) {
1572 		if (chan->cyclic)
1573 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1574 				     chan->cyclic_seg_v->phys);
1575 		else
1576 			xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
1577 				     tail_segment->phys);
1578 	} else {
1579 		struct xilinx_axidma_tx_segment *segment;
1580 		struct xilinx_axidma_desc_hw *hw;
1581 
1582 		segment = list_first_entry(&head_desc->segments,
1583 					   struct xilinx_axidma_tx_segment,
1584 					   node);
1585 		hw = &segment->hw;
1586 
1587 		xilinx_write(chan, XILINX_DMA_REG_SRCDSTADDR,
1588 			     xilinx_prep_dma_addr_t(hw->buf_addr));
1589 
1590 		/* Start the transfer */
1591 		dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
1592 			       hw->control & chan->xdev->max_buffer_len);
1593 	}
1594 
1595 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1596 	chan->desc_pendingcount = 0;
1597 	chan->idle = false;
1598 }
1599 
1600 /**
1601  * xilinx_mcdma_start_transfer - Starts MCDMA transfer
1602  * @chan: Driver specific channel struct pointer
1603  */
1604 static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan)
1605 {
1606 	struct xilinx_dma_tx_descriptor *head_desc, *tail_desc;
1607 	struct xilinx_aximcdma_tx_segment *tail_segment;
1608 	u32 reg;
1609 
1610 	/*
1611 	 * lock has been held by calling functions, so we don't need it
1612 	 * to take it here again.
1613 	 */
1614 
1615 	if (chan->err)
1616 		return;
1617 
1618 	if (!chan->idle)
1619 		return;
1620 
1621 	if (list_empty(&chan->pending_list))
1622 		return;
1623 
1624 	head_desc = list_first_entry(&chan->pending_list,
1625 				     struct xilinx_dma_tx_descriptor, node);
1626 	tail_desc = list_last_entry(&chan->pending_list,
1627 				    struct xilinx_dma_tx_descriptor, node);
1628 	tail_segment = list_last_entry(&tail_desc->segments,
1629 				       struct xilinx_aximcdma_tx_segment, node);
1630 
1631 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1632 
1633 	if (chan->desc_pendingcount <= XILINX_MCDMA_COALESCE_MAX) {
1634 		reg &= ~XILINX_MCDMA_COALESCE_MASK;
1635 		reg |= chan->desc_pendingcount <<
1636 			XILINX_MCDMA_COALESCE_SHIFT;
1637 	}
1638 
1639 	reg |= XILINX_MCDMA_IRQ_ALL_MASK;
1640 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1641 
1642 	/* Program current descriptor */
1643 	xilinx_write(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET(chan->tdest),
1644 		     head_desc->async_tx.phys);
1645 
1646 	/* Program channel enable register */
1647 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHEN_OFFSET);
1648 	reg |= BIT(chan->tdest);
1649 	dma_ctrl_write(chan, XILINX_MCDMA_CHEN_OFFSET, reg);
1650 
1651 	/* Start the fetch of BDs for the channel */
1652 	reg = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest));
1653 	reg |= XILINX_MCDMA_CR_RUNSTOP_MASK;
1654 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg);
1655 
1656 	xilinx_dma_start(chan);
1657 
1658 	if (chan->err)
1659 		return;
1660 
1661 	/* Start the transfer */
1662 	xilinx_write(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET(chan->tdest),
1663 		     tail_segment->phys);
1664 
1665 	list_splice_tail_init(&chan->pending_list, &chan->active_list);
1666 	chan->desc_pendingcount = 0;
1667 	chan->idle = false;
1668 }
1669 
1670 /**
1671  * xilinx_dma_issue_pending - Issue pending transactions
1672  * @dchan: DMA channel
1673  */
1674 static void xilinx_dma_issue_pending(struct dma_chan *dchan)
1675 {
1676 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
1677 	unsigned long flags;
1678 
1679 	spin_lock_irqsave(&chan->lock, flags);
1680 	chan->start_transfer(chan);
1681 	spin_unlock_irqrestore(&chan->lock, flags);
1682 }
1683 
1684 /**
1685  * xilinx_dma_device_config - Configure the DMA channel
1686  * @dchan: DMA channel
1687  * @config: channel configuration
1688  *
1689  * Return: 0 always.
1690  */
1691 static int xilinx_dma_device_config(struct dma_chan *dchan,
1692 				    struct dma_slave_config *config)
1693 {
1694 	return 0;
1695 }
1696 
1697 /**
1698  * xilinx_dma_complete_descriptor - Mark the active descriptor as complete
1699  * @chan : xilinx DMA channel
1700  *
1701  * CONTEXT: hardirq
1702  */
1703 static void xilinx_dma_complete_descriptor(struct xilinx_dma_chan *chan)
1704 {
1705 	struct xilinx_dma_tx_descriptor *desc, *next;
1706 
1707 	/* This function was invoked with lock held */
1708 	if (list_empty(&chan->active_list))
1709 		return;
1710 
1711 	list_for_each_entry_safe(desc, next, &chan->active_list, node) {
1712 		if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1713 			struct xilinx_axidma_tx_segment *seg;
1714 
1715 			seg = list_last_entry(&desc->segments,
1716 					      struct xilinx_axidma_tx_segment, node);
1717 			if (!(seg->hw.status & XILINX_DMA_BD_COMP_MASK) && chan->has_sg)
1718 				break;
1719 		}
1720 		if (chan->has_sg && chan->xdev->dma_config->dmatype !=
1721 		    XDMA_TYPE_VDMA)
1722 			desc->residue = xilinx_dma_get_residue(chan, desc);
1723 		else
1724 			desc->residue = 0;
1725 		desc->err = chan->err;
1726 
1727 		list_del(&desc->node);
1728 		if (!desc->cyclic)
1729 			dma_cookie_complete(&desc->async_tx);
1730 		list_add_tail(&desc->node, &chan->done_list);
1731 	}
1732 }
1733 
1734 /**
1735  * xilinx_dma_reset - Reset DMA channel
1736  * @chan: Driver specific DMA channel
1737  *
1738  * Return: '0' on success and failure value on error
1739  */
1740 static int xilinx_dma_reset(struct xilinx_dma_chan *chan)
1741 {
1742 	int err;
1743 	u32 tmp;
1744 
1745 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR, XILINX_DMA_DMACR_RESET);
1746 
1747 	/* Wait for the hardware to finish reset */
1748 	err = xilinx_dma_poll_timeout(chan, XILINX_DMA_REG_DMACR, tmp,
1749 				      !(tmp & XILINX_DMA_DMACR_RESET), 0,
1750 				      XILINX_DMA_LOOP_COUNT);
1751 
1752 	if (err) {
1753 		dev_err(chan->dev, "reset timeout, cr %x, sr %x\n",
1754 			dma_ctrl_read(chan, XILINX_DMA_REG_DMACR),
1755 			dma_ctrl_read(chan, XILINX_DMA_REG_DMASR));
1756 		return -ETIMEDOUT;
1757 	}
1758 
1759 	chan->err = false;
1760 	chan->idle = true;
1761 	chan->desc_pendingcount = 0;
1762 	chan->desc_submitcount = 0;
1763 
1764 	return err;
1765 }
1766 
1767 /**
1768  * xilinx_dma_chan_reset - Reset DMA channel and enable interrupts
1769  * @chan: Driver specific DMA channel
1770  *
1771  * Return: '0' on success and failure value on error
1772  */
1773 static int xilinx_dma_chan_reset(struct xilinx_dma_chan *chan)
1774 {
1775 	int err;
1776 
1777 	/* Reset VDMA */
1778 	err = xilinx_dma_reset(chan);
1779 	if (err)
1780 		return err;
1781 
1782 	/* Enable interrupts */
1783 	dma_ctrl_set(chan, XILINX_DMA_REG_DMACR,
1784 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1785 
1786 	return 0;
1787 }
1788 
1789 /**
1790  * xilinx_mcdma_irq_handler - MCDMA Interrupt handler
1791  * @irq: IRQ number
1792  * @data: Pointer to the Xilinx MCDMA channel structure
1793  *
1794  * Return: IRQ_HANDLED/IRQ_NONE
1795  */
1796 static irqreturn_t xilinx_mcdma_irq_handler(int irq, void *data)
1797 {
1798 	struct xilinx_dma_chan *chan = data;
1799 	u32 status, ser_offset, chan_sermask, chan_offset = 0, chan_id;
1800 
1801 	if (chan->direction == DMA_DEV_TO_MEM)
1802 		ser_offset = XILINX_MCDMA_RXINT_SER_OFFSET;
1803 	else
1804 		ser_offset = XILINX_MCDMA_TXINT_SER_OFFSET;
1805 
1806 	/* Read the channel id raising the interrupt*/
1807 	chan_sermask = dma_ctrl_read(chan, ser_offset);
1808 	chan_id = ffs(chan_sermask);
1809 
1810 	if (!chan_id)
1811 		return IRQ_NONE;
1812 
1813 	if (chan->direction == DMA_DEV_TO_MEM)
1814 		chan_offset = chan->xdev->dma_config->max_channels / 2;
1815 
1816 	chan_offset = chan_offset + (chan_id - 1);
1817 	chan = chan->xdev->chan[chan_offset];
1818 	/* Read the status and ack the interrupts. */
1819 	status = dma_ctrl_read(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest));
1820 	if (!(status & XILINX_MCDMA_IRQ_ALL_MASK))
1821 		return IRQ_NONE;
1822 
1823 	dma_ctrl_write(chan, XILINX_MCDMA_CHAN_SR_OFFSET(chan->tdest),
1824 		       status & XILINX_MCDMA_IRQ_ALL_MASK);
1825 
1826 	if (status & XILINX_MCDMA_IRQ_ERR_MASK) {
1827 		dev_err(chan->dev, "Channel %p has errors %x cdr %x tdr %x\n",
1828 			chan,
1829 			dma_ctrl_read(chan, XILINX_MCDMA_CH_ERR_OFFSET),
1830 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_CDESC_OFFSET
1831 				      (chan->tdest)),
1832 			dma_ctrl_read(chan, XILINX_MCDMA_CHAN_TDESC_OFFSET
1833 				      (chan->tdest)));
1834 		chan->err = true;
1835 	}
1836 
1837 	if (status & XILINX_MCDMA_IRQ_DELAY_MASK) {
1838 		/*
1839 		 * Device takes too long to do the transfer when user requires
1840 		 * responsiveness.
1841 		 */
1842 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1843 	}
1844 
1845 	if (status & XILINX_MCDMA_IRQ_IOC_MASK) {
1846 		spin_lock(&chan->lock);
1847 		xilinx_dma_complete_descriptor(chan);
1848 		chan->idle = true;
1849 		chan->start_transfer(chan);
1850 		spin_unlock(&chan->lock);
1851 	}
1852 
1853 	tasklet_hi_schedule(&chan->tasklet);
1854 	return IRQ_HANDLED;
1855 }
1856 
1857 /**
1858  * xilinx_dma_irq_handler - DMA Interrupt handler
1859  * @irq: IRQ number
1860  * @data: Pointer to the Xilinx DMA channel structure
1861  *
1862  * Return: IRQ_HANDLED/IRQ_NONE
1863  */
1864 static irqreturn_t xilinx_dma_irq_handler(int irq, void *data)
1865 {
1866 	struct xilinx_dma_chan *chan = data;
1867 	u32 status;
1868 
1869 	/* Read the status and ack the interrupts. */
1870 	status = dma_ctrl_read(chan, XILINX_DMA_REG_DMASR);
1871 	if (!(status & XILINX_DMA_DMAXR_ALL_IRQ_MASK))
1872 		return IRQ_NONE;
1873 
1874 	dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1875 			status & XILINX_DMA_DMAXR_ALL_IRQ_MASK);
1876 
1877 	if (status & XILINX_DMA_DMASR_ERR_IRQ) {
1878 		/*
1879 		 * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the
1880 		 * error is recoverable, ignore it. Otherwise flag the error.
1881 		 *
1882 		 * Only recoverable errors can be cleared in the DMASR register,
1883 		 * make sure not to write to other error bits to 1.
1884 		 */
1885 		u32 errors = status & XILINX_DMA_DMASR_ALL_ERR_MASK;
1886 
1887 		dma_ctrl_write(chan, XILINX_DMA_REG_DMASR,
1888 				errors & XILINX_DMA_DMASR_ERR_RECOVER_MASK);
1889 
1890 		if (!chan->flush_on_fsync ||
1891 		    (errors & ~XILINX_DMA_DMASR_ERR_RECOVER_MASK)) {
1892 			dev_err(chan->dev,
1893 				"Channel %p has errors %x, cdr %x tdr %x\n",
1894 				chan, errors,
1895 				dma_ctrl_read(chan, XILINX_DMA_REG_CURDESC),
1896 				dma_ctrl_read(chan, XILINX_DMA_REG_TAILDESC));
1897 			chan->err = true;
1898 		}
1899 	}
1900 
1901 	if (status & XILINX_DMA_DMASR_DLY_CNT_IRQ) {
1902 		/*
1903 		 * Device takes too long to do the transfer when user requires
1904 		 * responsiveness.
1905 		 */
1906 		dev_dbg(chan->dev, "Inter-packet latency too long\n");
1907 	}
1908 
1909 	if (status & XILINX_DMA_DMASR_FRM_CNT_IRQ) {
1910 		spin_lock(&chan->lock);
1911 		xilinx_dma_complete_descriptor(chan);
1912 		chan->idle = true;
1913 		chan->start_transfer(chan);
1914 		spin_unlock(&chan->lock);
1915 	}
1916 
1917 	tasklet_schedule(&chan->tasklet);
1918 	return IRQ_HANDLED;
1919 }
1920 
1921 /**
1922  * append_desc_queue - Queuing descriptor
1923  * @chan: Driver specific dma channel
1924  * @desc: dma transaction descriptor
1925  */
1926 static void append_desc_queue(struct xilinx_dma_chan *chan,
1927 			      struct xilinx_dma_tx_descriptor *desc)
1928 {
1929 	struct xilinx_vdma_tx_segment *tail_segment;
1930 	struct xilinx_dma_tx_descriptor *tail_desc;
1931 	struct xilinx_axidma_tx_segment *axidma_tail_segment;
1932 	struct xilinx_aximcdma_tx_segment *aximcdma_tail_segment;
1933 	struct xilinx_cdma_tx_segment *cdma_tail_segment;
1934 
1935 	if (list_empty(&chan->pending_list))
1936 		goto append;
1937 
1938 	/*
1939 	 * Add the hardware descriptor to the chain of hardware descriptors
1940 	 * that already exists in memory.
1941 	 */
1942 	tail_desc = list_last_entry(&chan->pending_list,
1943 				    struct xilinx_dma_tx_descriptor, node);
1944 	if (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
1945 		tail_segment = list_last_entry(&tail_desc->segments,
1946 					       struct xilinx_vdma_tx_segment,
1947 					       node);
1948 		tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1949 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
1950 		cdma_tail_segment = list_last_entry(&tail_desc->segments,
1951 						struct xilinx_cdma_tx_segment,
1952 						node);
1953 		cdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1954 	} else if (chan->xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
1955 		axidma_tail_segment = list_last_entry(&tail_desc->segments,
1956 					       struct xilinx_axidma_tx_segment,
1957 					       node);
1958 		axidma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1959 	} else {
1960 		aximcdma_tail_segment =
1961 			list_last_entry(&tail_desc->segments,
1962 					struct xilinx_aximcdma_tx_segment,
1963 					node);
1964 		aximcdma_tail_segment->hw.next_desc = (u32)desc->async_tx.phys;
1965 	}
1966 
1967 	/*
1968 	 * Add the software descriptor and all children to the list
1969 	 * of pending transactions
1970 	 */
1971 append:
1972 	list_add_tail(&desc->node, &chan->pending_list);
1973 	chan->desc_pendingcount++;
1974 
1975 	if (chan->has_sg && (chan->xdev->dma_config->dmatype == XDMA_TYPE_VDMA)
1976 	    && unlikely(chan->desc_pendingcount > chan->num_frms)) {
1977 		dev_dbg(chan->dev, "desc pendingcount is too high\n");
1978 		chan->desc_pendingcount = chan->num_frms;
1979 	}
1980 }
1981 
1982 /**
1983  * xilinx_dma_tx_submit - Submit DMA transaction
1984  * @tx: Async transaction descriptor
1985  *
1986  * Return: cookie value on success and failure value on error
1987  */
1988 static dma_cookie_t xilinx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
1989 {
1990 	struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
1991 	struct xilinx_dma_chan *chan = to_xilinx_chan(tx->chan);
1992 	dma_cookie_t cookie;
1993 	unsigned long flags;
1994 	int err;
1995 
1996 	if (chan->cyclic) {
1997 		xilinx_dma_free_tx_descriptor(chan, desc);
1998 		return -EBUSY;
1999 	}
2000 
2001 	if (chan->err) {
2002 		/*
2003 		 * If reset fails, need to hard reset the system.
2004 		 * Channel is no longer functional
2005 		 */
2006 		err = xilinx_dma_chan_reset(chan);
2007 		if (err < 0)
2008 			return err;
2009 	}
2010 
2011 	spin_lock_irqsave(&chan->lock, flags);
2012 
2013 	cookie = dma_cookie_assign(tx);
2014 
2015 	/* Put this transaction onto the tail of the pending queue */
2016 	append_desc_queue(chan, desc);
2017 
2018 	if (desc->cyclic)
2019 		chan->cyclic = true;
2020 
2021 	chan->terminating = false;
2022 
2023 	spin_unlock_irqrestore(&chan->lock, flags);
2024 
2025 	return cookie;
2026 }
2027 
2028 /**
2029  * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a
2030  *	DMA_SLAVE transaction
2031  * @dchan: DMA channel
2032  * @xt: Interleaved template pointer
2033  * @flags: transfer ack flags
2034  *
2035  * Return: Async transaction descriptor on success and NULL on failure
2036  */
2037 static struct dma_async_tx_descriptor *
2038 xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan,
2039 				 struct dma_interleaved_template *xt,
2040 				 unsigned long flags)
2041 {
2042 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2043 	struct xilinx_dma_tx_descriptor *desc;
2044 	struct xilinx_vdma_tx_segment *segment;
2045 	struct xilinx_vdma_desc_hw *hw;
2046 
2047 	if (!is_slave_direction(xt->dir))
2048 		return NULL;
2049 
2050 	if (!xt->numf || !xt->sgl[0].size)
2051 		return NULL;
2052 
2053 	if (xt->frame_size != 1)
2054 		return NULL;
2055 
2056 	/* Allocate a transaction descriptor. */
2057 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2058 	if (!desc)
2059 		return NULL;
2060 
2061 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2062 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2063 	async_tx_ack(&desc->async_tx);
2064 
2065 	/* Allocate the link descriptor from DMA pool */
2066 	segment = xilinx_vdma_alloc_tx_segment(chan);
2067 	if (!segment)
2068 		goto error;
2069 
2070 	/* Fill in the hardware descriptor */
2071 	hw = &segment->hw;
2072 	hw->vsize = xt->numf;
2073 	hw->hsize = xt->sgl[0].size;
2074 	hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) <<
2075 			XILINX_DMA_FRMDLY_STRIDE_STRIDE_SHIFT;
2076 	hw->stride |= chan->config.frm_dly <<
2077 			XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT;
2078 
2079 	if (xt->dir != DMA_MEM_TO_DEV) {
2080 		if (chan->ext_addr) {
2081 			hw->buf_addr = lower_32_bits(xt->dst_start);
2082 			hw->buf_addr_msb = upper_32_bits(xt->dst_start);
2083 		} else {
2084 			hw->buf_addr = xt->dst_start;
2085 		}
2086 	} else {
2087 		if (chan->ext_addr) {
2088 			hw->buf_addr = lower_32_bits(xt->src_start);
2089 			hw->buf_addr_msb = upper_32_bits(xt->src_start);
2090 		} else {
2091 			hw->buf_addr = xt->src_start;
2092 		}
2093 	}
2094 
2095 	/* Insert the segment into the descriptor segments list. */
2096 	list_add_tail(&segment->node, &desc->segments);
2097 
2098 	/* Link the last hardware descriptor with the first. */
2099 	segment = list_first_entry(&desc->segments,
2100 				   struct xilinx_vdma_tx_segment, node);
2101 	desc->async_tx.phys = segment->phys;
2102 
2103 	return &desc->async_tx;
2104 
2105 error:
2106 	xilinx_dma_free_tx_descriptor(chan, desc);
2107 	return NULL;
2108 }
2109 
2110 /**
2111  * xilinx_cdma_prep_memcpy - prepare descriptors for a memcpy transaction
2112  * @dchan: DMA channel
2113  * @dma_dst: destination address
2114  * @dma_src: source address
2115  * @len: transfer length
2116  * @flags: transfer ack flags
2117  *
2118  * Return: Async transaction descriptor on success and NULL on failure
2119  */
2120 static struct dma_async_tx_descriptor *
2121 xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
2122 			dma_addr_t dma_src, size_t len, unsigned long flags)
2123 {
2124 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2125 	struct xilinx_dma_tx_descriptor *desc;
2126 	struct xilinx_cdma_tx_segment *segment;
2127 	struct xilinx_cdma_desc_hw *hw;
2128 
2129 	if (!len || len > chan->xdev->max_buffer_len)
2130 		return NULL;
2131 
2132 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2133 	if (!desc)
2134 		return NULL;
2135 
2136 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2137 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2138 
2139 	/* Allocate the link descriptor from DMA pool */
2140 	segment = xilinx_cdma_alloc_tx_segment(chan);
2141 	if (!segment)
2142 		goto error;
2143 
2144 	hw = &segment->hw;
2145 	hw->control = len;
2146 	hw->src_addr = dma_src;
2147 	hw->dest_addr = dma_dst;
2148 	if (chan->ext_addr) {
2149 		hw->src_addr_msb = upper_32_bits(dma_src);
2150 		hw->dest_addr_msb = upper_32_bits(dma_dst);
2151 	}
2152 
2153 	/* Insert the segment into the descriptor segments list. */
2154 	list_add_tail(&segment->node, &desc->segments);
2155 
2156 	desc->async_tx.phys = segment->phys;
2157 	hw->next_desc = segment->phys;
2158 
2159 	return &desc->async_tx;
2160 
2161 error:
2162 	xilinx_dma_free_tx_descriptor(chan, desc);
2163 	return NULL;
2164 }
2165 
2166 /**
2167  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2168  * @dchan: DMA channel
2169  * @sgl: scatterlist to transfer to/from
2170  * @sg_len: number of entries in @scatterlist
2171  * @direction: DMA direction
2172  * @flags: transfer ack flags
2173  * @context: APP words of the descriptor
2174  *
2175  * Return: Async transaction descriptor on success and NULL on failure
2176  */
2177 static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
2178 	struct dma_chan *dchan, struct scatterlist *sgl, unsigned int sg_len,
2179 	enum dma_transfer_direction direction, unsigned long flags,
2180 	void *context)
2181 {
2182 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2183 	struct xilinx_dma_tx_descriptor *desc;
2184 	struct xilinx_axidma_tx_segment *segment = NULL;
2185 	u32 *app_w = (u32 *)context;
2186 	struct scatterlist *sg;
2187 	size_t copy;
2188 	size_t sg_used;
2189 	unsigned int i;
2190 
2191 	if (!is_slave_direction(direction))
2192 		return NULL;
2193 
2194 	/* Allocate a transaction descriptor. */
2195 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2196 	if (!desc)
2197 		return NULL;
2198 
2199 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2200 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2201 
2202 	/* Build transactions using information in the scatter gather list */
2203 	for_each_sg(sgl, sg, sg_len, i) {
2204 		sg_used = 0;
2205 
2206 		/* Loop until the entire scatterlist entry is used */
2207 		while (sg_used < sg_dma_len(sg)) {
2208 			struct xilinx_axidma_desc_hw *hw;
2209 
2210 			/* Get a free segment */
2211 			segment = xilinx_axidma_alloc_tx_segment(chan);
2212 			if (!segment)
2213 				goto error;
2214 
2215 			/*
2216 			 * Calculate the maximum number of bytes to transfer,
2217 			 * making sure it is less than the hw limit
2218 			 */
2219 			copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
2220 							sg_used);
2221 			hw = &segment->hw;
2222 
2223 			/* Fill in the descriptor */
2224 			xilinx_axidma_buf(chan, hw, sg_dma_address(sg),
2225 					  sg_used, 0);
2226 
2227 			hw->control = copy;
2228 
2229 			if (chan->direction == DMA_MEM_TO_DEV) {
2230 				if (app_w)
2231 					memcpy(hw->app, app_w, sizeof(u32) *
2232 					       XILINX_DMA_NUM_APP_WORDS);
2233 			}
2234 
2235 			sg_used += copy;
2236 
2237 			/*
2238 			 * Insert the segment into the descriptor segments
2239 			 * list.
2240 			 */
2241 			list_add_tail(&segment->node, &desc->segments);
2242 		}
2243 	}
2244 
2245 	segment = list_first_entry(&desc->segments,
2246 				   struct xilinx_axidma_tx_segment, node);
2247 	desc->async_tx.phys = segment->phys;
2248 
2249 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2250 	if (chan->direction == DMA_MEM_TO_DEV) {
2251 		segment->hw.control |= XILINX_DMA_BD_SOP;
2252 		segment = list_last_entry(&desc->segments,
2253 					  struct xilinx_axidma_tx_segment,
2254 					  node);
2255 		segment->hw.control |= XILINX_DMA_BD_EOP;
2256 	}
2257 
2258 	if (chan->xdev->has_axistream_connected)
2259 		desc->async_tx.metadata_ops = &xilinx_dma_metadata_ops;
2260 
2261 	return &desc->async_tx;
2262 
2263 error:
2264 	xilinx_dma_free_tx_descriptor(chan, desc);
2265 	return NULL;
2266 }
2267 
2268 /**
2269  * xilinx_dma_prep_dma_cyclic - prepare descriptors for a DMA_SLAVE transaction
2270  * @dchan: DMA channel
2271  * @buf_addr: Physical address of the buffer
2272  * @buf_len: Total length of the cyclic buffers
2273  * @period_len: length of individual cyclic buffer
2274  * @direction: DMA direction
2275  * @flags: transfer ack flags
2276  *
2277  * Return: Async transaction descriptor on success and NULL on failure
2278  */
2279 static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
2280 	struct dma_chan *dchan, dma_addr_t buf_addr, size_t buf_len,
2281 	size_t period_len, enum dma_transfer_direction direction,
2282 	unsigned long flags)
2283 {
2284 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2285 	struct xilinx_dma_tx_descriptor *desc;
2286 	struct xilinx_axidma_tx_segment *segment, *head_segment, *prev = NULL;
2287 	size_t copy, sg_used;
2288 	unsigned int num_periods;
2289 	int i;
2290 	u32 reg;
2291 
2292 	if (!period_len)
2293 		return NULL;
2294 
2295 	num_periods = buf_len / period_len;
2296 
2297 	if (!num_periods)
2298 		return NULL;
2299 
2300 	if (!is_slave_direction(direction))
2301 		return NULL;
2302 
2303 	/* Allocate a transaction descriptor. */
2304 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2305 	if (!desc)
2306 		return NULL;
2307 
2308 	chan->direction = direction;
2309 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2310 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2311 
2312 	for (i = 0; i < num_periods; ++i) {
2313 		sg_used = 0;
2314 
2315 		while (sg_used < period_len) {
2316 			struct xilinx_axidma_desc_hw *hw;
2317 
2318 			/* Get a free segment */
2319 			segment = xilinx_axidma_alloc_tx_segment(chan);
2320 			if (!segment)
2321 				goto error;
2322 
2323 			/*
2324 			 * Calculate the maximum number of bytes to transfer,
2325 			 * making sure it is less than the hw limit
2326 			 */
2327 			copy = xilinx_dma_calc_copysize(chan, period_len,
2328 							sg_used);
2329 			hw = &segment->hw;
2330 			xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
2331 					  period_len * i);
2332 			hw->control = copy;
2333 
2334 			if (prev)
2335 				prev->hw.next_desc = segment->phys;
2336 
2337 			prev = segment;
2338 			sg_used += copy;
2339 
2340 			/*
2341 			 * Insert the segment into the descriptor segments
2342 			 * list.
2343 			 */
2344 			list_add_tail(&segment->node, &desc->segments);
2345 		}
2346 	}
2347 
2348 	head_segment = list_first_entry(&desc->segments,
2349 				   struct xilinx_axidma_tx_segment, node);
2350 	desc->async_tx.phys = head_segment->phys;
2351 
2352 	desc->cyclic = true;
2353 	reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2354 	reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2355 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2356 
2357 	segment = list_last_entry(&desc->segments,
2358 				  struct xilinx_axidma_tx_segment,
2359 				  node);
2360 	segment->hw.next_desc = (u32) head_segment->phys;
2361 
2362 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2363 	if (direction == DMA_MEM_TO_DEV) {
2364 		head_segment->hw.control |= XILINX_DMA_BD_SOP;
2365 		segment->hw.control |= XILINX_DMA_BD_EOP;
2366 	}
2367 
2368 	return &desc->async_tx;
2369 
2370 error:
2371 	xilinx_dma_free_tx_descriptor(chan, desc);
2372 	return NULL;
2373 }
2374 
2375 /**
2376  * xilinx_mcdma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
2377  * @dchan: DMA channel
2378  * @sgl: scatterlist to transfer to/from
2379  * @sg_len: number of entries in @scatterlist
2380  * @direction: DMA direction
2381  * @flags: transfer ack flags
2382  * @context: APP words of the descriptor
2383  *
2384  * Return: Async transaction descriptor on success and NULL on failure
2385  */
2386 static struct dma_async_tx_descriptor *
2387 xilinx_mcdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
2388 			   unsigned int sg_len,
2389 			   enum dma_transfer_direction direction,
2390 			   unsigned long flags, void *context)
2391 {
2392 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2393 	struct xilinx_dma_tx_descriptor *desc;
2394 	struct xilinx_aximcdma_tx_segment *segment = NULL;
2395 	u32 *app_w = (u32 *)context;
2396 	struct scatterlist *sg;
2397 	size_t copy;
2398 	size_t sg_used;
2399 	unsigned int i;
2400 
2401 	if (!is_slave_direction(direction))
2402 		return NULL;
2403 
2404 	/* Allocate a transaction descriptor. */
2405 	desc = xilinx_dma_alloc_tx_descriptor(chan);
2406 	if (!desc)
2407 		return NULL;
2408 
2409 	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
2410 	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
2411 
2412 	/* Build transactions using information in the scatter gather list */
2413 	for_each_sg(sgl, sg, sg_len, i) {
2414 		sg_used = 0;
2415 
2416 		/* Loop until the entire scatterlist entry is used */
2417 		while (sg_used < sg_dma_len(sg)) {
2418 			struct xilinx_aximcdma_desc_hw *hw;
2419 
2420 			/* Get a free segment */
2421 			segment = xilinx_aximcdma_alloc_tx_segment(chan);
2422 			if (!segment)
2423 				goto error;
2424 
2425 			/*
2426 			 * Calculate the maximum number of bytes to transfer,
2427 			 * making sure it is less than the hw limit
2428 			 */
2429 			copy = min_t(size_t, sg_dma_len(sg) - sg_used,
2430 				     chan->xdev->max_buffer_len);
2431 			hw = &segment->hw;
2432 
2433 			/* Fill in the descriptor */
2434 			xilinx_aximcdma_buf(chan, hw, sg_dma_address(sg),
2435 					    sg_used);
2436 			hw->control = copy;
2437 
2438 			if (chan->direction == DMA_MEM_TO_DEV && app_w) {
2439 				memcpy(hw->app, app_w, sizeof(u32) *
2440 				       XILINX_DMA_NUM_APP_WORDS);
2441 			}
2442 
2443 			sg_used += copy;
2444 			/*
2445 			 * Insert the segment into the descriptor segments
2446 			 * list.
2447 			 */
2448 			list_add_tail(&segment->node, &desc->segments);
2449 		}
2450 	}
2451 
2452 	segment = list_first_entry(&desc->segments,
2453 				   struct xilinx_aximcdma_tx_segment, node);
2454 	desc->async_tx.phys = segment->phys;
2455 
2456 	/* For the last DMA_MEM_TO_DEV transfer, set EOP */
2457 	if (chan->direction == DMA_MEM_TO_DEV) {
2458 		segment->hw.control |= XILINX_MCDMA_BD_SOP;
2459 		segment = list_last_entry(&desc->segments,
2460 					  struct xilinx_aximcdma_tx_segment,
2461 					  node);
2462 		segment->hw.control |= XILINX_MCDMA_BD_EOP;
2463 	}
2464 
2465 	return &desc->async_tx;
2466 
2467 error:
2468 	xilinx_dma_free_tx_descriptor(chan, desc);
2469 
2470 	return NULL;
2471 }
2472 
2473 /**
2474  * xilinx_dma_terminate_all - Halt the channel and free descriptors
2475  * @dchan: Driver specific DMA Channel pointer
2476  *
2477  * Return: '0' always.
2478  */
2479 static int xilinx_dma_terminate_all(struct dma_chan *dchan)
2480 {
2481 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2482 	u32 reg;
2483 	int err;
2484 
2485 	if (!chan->cyclic) {
2486 		err = chan->stop_transfer(chan);
2487 		if (err) {
2488 			dev_err(chan->dev, "Cannot stop channel %p: %x\n",
2489 				chan, dma_ctrl_read(chan,
2490 				XILINX_DMA_REG_DMASR));
2491 			chan->err = true;
2492 		}
2493 	}
2494 
2495 	xilinx_dma_chan_reset(chan);
2496 	/* Remove and free all of the descriptors in the lists */
2497 	chan->terminating = true;
2498 	xilinx_dma_free_descriptors(chan);
2499 	chan->idle = true;
2500 
2501 	if (chan->cyclic) {
2502 		reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2503 		reg &= ~XILINX_DMA_CR_CYCLIC_BD_EN_MASK;
2504 		dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
2505 		chan->cyclic = false;
2506 	}
2507 
2508 	if ((chan->xdev->dma_config->dmatype == XDMA_TYPE_CDMA) && chan->has_sg)
2509 		dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2510 			     XILINX_CDMA_CR_SGMODE);
2511 
2512 	return 0;
2513 }
2514 
2515 static void xilinx_dma_synchronize(struct dma_chan *dchan)
2516 {
2517 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2518 
2519 	tasklet_kill(&chan->tasklet);
2520 }
2521 
2522 /**
2523  * xilinx_vdma_channel_set_config - Configure VDMA channel
2524  * Run-time configuration for Axi VDMA, supports:
2525  * . halt the channel
2526  * . configure interrupt coalescing and inter-packet delay threshold
2527  * . start/stop parking
2528  * . enable genlock
2529  *
2530  * @dchan: DMA channel
2531  * @cfg: VDMA device configuration pointer
2532  *
2533  * Return: '0' on success and failure value on error
2534  */
2535 int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
2536 					struct xilinx_vdma_config *cfg)
2537 {
2538 	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
2539 	u32 dmacr;
2540 
2541 	if (cfg->reset)
2542 		return xilinx_dma_chan_reset(chan);
2543 
2544 	dmacr = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
2545 
2546 	chan->config.frm_dly = cfg->frm_dly;
2547 	chan->config.park = cfg->park;
2548 
2549 	/* genlock settings */
2550 	chan->config.gen_lock = cfg->gen_lock;
2551 	chan->config.master = cfg->master;
2552 
2553 	dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
2554 	if (cfg->gen_lock && chan->genlock) {
2555 		dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
2556 		dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
2557 		dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
2558 	}
2559 
2560 	chan->config.frm_cnt_en = cfg->frm_cnt_en;
2561 	chan->config.vflip_en = cfg->vflip_en;
2562 
2563 	if (cfg->park)
2564 		chan->config.park_frm = cfg->park_frm;
2565 	else
2566 		chan->config.park_frm = -1;
2567 
2568 	chan->config.coalesc = cfg->coalesc;
2569 	chan->config.delay = cfg->delay;
2570 
2571 	if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
2572 		dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
2573 		dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
2574 		chan->config.coalesc = cfg->coalesc;
2575 	}
2576 
2577 	if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
2578 		dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
2579 		dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
2580 		chan->config.delay = cfg->delay;
2581 	}
2582 
2583 	/* FSync Source selection */
2584 	dmacr &= ~XILINX_DMA_DMACR_FSYNCSRC_MASK;
2585 	dmacr |= cfg->ext_fsync << XILINX_DMA_DMACR_FSYNCSRC_SHIFT;
2586 
2587 	dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, dmacr);
2588 
2589 	return 0;
2590 }
2591 EXPORT_SYMBOL(xilinx_vdma_channel_set_config);
2592 
2593 /* -----------------------------------------------------------------------------
2594  * Probe and remove
2595  */
2596 
2597 /**
2598  * xilinx_dma_chan_remove - Per Channel remove function
2599  * @chan: Driver specific DMA channel
2600  */
2601 static void xilinx_dma_chan_remove(struct xilinx_dma_chan *chan)
2602 {
2603 	/* Disable all interrupts */
2604 	dma_ctrl_clr(chan, XILINX_DMA_REG_DMACR,
2605 		      XILINX_DMA_DMAXR_ALL_IRQ_MASK);
2606 
2607 	if (chan->irq > 0)
2608 		free_irq(chan->irq, chan);
2609 
2610 	tasklet_kill(&chan->tasklet);
2611 
2612 	list_del(&chan->common.device_node);
2613 }
2614 
2615 static int axidma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2616 			    struct clk **tx_clk, struct clk **rx_clk,
2617 			    struct clk **sg_clk, struct clk **tmp_clk)
2618 {
2619 	int err;
2620 
2621 	*tmp_clk = NULL;
2622 
2623 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2624 	if (IS_ERR(*axi_clk))
2625 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2626 
2627 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2628 	if (IS_ERR(*tx_clk))
2629 		*tx_clk = NULL;
2630 
2631 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2632 	if (IS_ERR(*rx_clk))
2633 		*rx_clk = NULL;
2634 
2635 	*sg_clk = devm_clk_get(&pdev->dev, "m_axi_sg_aclk");
2636 	if (IS_ERR(*sg_clk))
2637 		*sg_clk = NULL;
2638 
2639 	err = clk_prepare_enable(*axi_clk);
2640 	if (err) {
2641 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2642 		return err;
2643 	}
2644 
2645 	err = clk_prepare_enable(*tx_clk);
2646 	if (err) {
2647 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2648 		goto err_disable_axiclk;
2649 	}
2650 
2651 	err = clk_prepare_enable(*rx_clk);
2652 	if (err) {
2653 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2654 		goto err_disable_txclk;
2655 	}
2656 
2657 	err = clk_prepare_enable(*sg_clk);
2658 	if (err) {
2659 		dev_err(&pdev->dev, "failed to enable sg_clk (%d)\n", err);
2660 		goto err_disable_rxclk;
2661 	}
2662 
2663 	return 0;
2664 
2665 err_disable_rxclk:
2666 	clk_disable_unprepare(*rx_clk);
2667 err_disable_txclk:
2668 	clk_disable_unprepare(*tx_clk);
2669 err_disable_axiclk:
2670 	clk_disable_unprepare(*axi_clk);
2671 
2672 	return err;
2673 }
2674 
2675 static int axicdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2676 			    struct clk **dev_clk, struct clk **tmp_clk,
2677 			    struct clk **tmp1_clk, struct clk **tmp2_clk)
2678 {
2679 	int err;
2680 
2681 	*tmp_clk = NULL;
2682 	*tmp1_clk = NULL;
2683 	*tmp2_clk = NULL;
2684 
2685 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2686 	if (IS_ERR(*axi_clk))
2687 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2688 
2689 	*dev_clk = devm_clk_get(&pdev->dev, "m_axi_aclk");
2690 	if (IS_ERR(*dev_clk))
2691 		return dev_err_probe(&pdev->dev, PTR_ERR(*dev_clk), "failed to get dev_clk\n");
2692 
2693 	err = clk_prepare_enable(*axi_clk);
2694 	if (err) {
2695 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n", err);
2696 		return err;
2697 	}
2698 
2699 	err = clk_prepare_enable(*dev_clk);
2700 	if (err) {
2701 		dev_err(&pdev->dev, "failed to enable dev_clk (%d)\n", err);
2702 		goto err_disable_axiclk;
2703 	}
2704 
2705 	return 0;
2706 
2707 err_disable_axiclk:
2708 	clk_disable_unprepare(*axi_clk);
2709 
2710 	return err;
2711 }
2712 
2713 static int axivdma_clk_init(struct platform_device *pdev, struct clk **axi_clk,
2714 			    struct clk **tx_clk, struct clk **txs_clk,
2715 			    struct clk **rx_clk, struct clk **rxs_clk)
2716 {
2717 	int err;
2718 
2719 	*axi_clk = devm_clk_get(&pdev->dev, "s_axi_lite_aclk");
2720 	if (IS_ERR(*axi_clk))
2721 		return dev_err_probe(&pdev->dev, PTR_ERR(*axi_clk), "failed to get axi_aclk\n");
2722 
2723 	*tx_clk = devm_clk_get(&pdev->dev, "m_axi_mm2s_aclk");
2724 	if (IS_ERR(*tx_clk))
2725 		*tx_clk = NULL;
2726 
2727 	*txs_clk = devm_clk_get(&pdev->dev, "m_axis_mm2s_aclk");
2728 	if (IS_ERR(*txs_clk))
2729 		*txs_clk = NULL;
2730 
2731 	*rx_clk = devm_clk_get(&pdev->dev, "m_axi_s2mm_aclk");
2732 	if (IS_ERR(*rx_clk))
2733 		*rx_clk = NULL;
2734 
2735 	*rxs_clk = devm_clk_get(&pdev->dev, "s_axis_s2mm_aclk");
2736 	if (IS_ERR(*rxs_clk))
2737 		*rxs_clk = NULL;
2738 
2739 	err = clk_prepare_enable(*axi_clk);
2740 	if (err) {
2741 		dev_err(&pdev->dev, "failed to enable axi_clk (%d)\n",
2742 			err);
2743 		return err;
2744 	}
2745 
2746 	err = clk_prepare_enable(*tx_clk);
2747 	if (err) {
2748 		dev_err(&pdev->dev, "failed to enable tx_clk (%d)\n", err);
2749 		goto err_disable_axiclk;
2750 	}
2751 
2752 	err = clk_prepare_enable(*txs_clk);
2753 	if (err) {
2754 		dev_err(&pdev->dev, "failed to enable txs_clk (%d)\n", err);
2755 		goto err_disable_txclk;
2756 	}
2757 
2758 	err = clk_prepare_enable(*rx_clk);
2759 	if (err) {
2760 		dev_err(&pdev->dev, "failed to enable rx_clk (%d)\n", err);
2761 		goto err_disable_txsclk;
2762 	}
2763 
2764 	err = clk_prepare_enable(*rxs_clk);
2765 	if (err) {
2766 		dev_err(&pdev->dev, "failed to enable rxs_clk (%d)\n", err);
2767 		goto err_disable_rxclk;
2768 	}
2769 
2770 	return 0;
2771 
2772 err_disable_rxclk:
2773 	clk_disable_unprepare(*rx_clk);
2774 err_disable_txsclk:
2775 	clk_disable_unprepare(*txs_clk);
2776 err_disable_txclk:
2777 	clk_disable_unprepare(*tx_clk);
2778 err_disable_axiclk:
2779 	clk_disable_unprepare(*axi_clk);
2780 
2781 	return err;
2782 }
2783 
2784 static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
2785 {
2786 	clk_disable_unprepare(xdev->rxs_clk);
2787 	clk_disable_unprepare(xdev->rx_clk);
2788 	clk_disable_unprepare(xdev->txs_clk);
2789 	clk_disable_unprepare(xdev->tx_clk);
2790 	clk_disable_unprepare(xdev->axi_clk);
2791 }
2792 
2793 /**
2794  * xilinx_dma_chan_probe - Per Channel Probing
2795  * It get channel features from the device tree entry and
2796  * initialize special channel handling routines
2797  *
2798  * @xdev: Driver specific device structure
2799  * @node: Device node
2800  *
2801  * Return: '0' on success and failure value on error
2802  */
2803 static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
2804 				  struct device_node *node)
2805 {
2806 	struct xilinx_dma_chan *chan;
2807 	bool has_dre = false;
2808 	u32 value, width;
2809 	int err;
2810 
2811 	/* Allocate and initialize the channel structure */
2812 	chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL);
2813 	if (!chan)
2814 		return -ENOMEM;
2815 
2816 	chan->dev = xdev->dev;
2817 	chan->xdev = xdev;
2818 	chan->desc_pendingcount = 0x0;
2819 	chan->ext_addr = xdev->ext_addr;
2820 	/* This variable ensures that descriptors are not
2821 	 * Submitted when dma engine is in progress. This variable is
2822 	 * Added to avoid polling for a bit in the status register to
2823 	 * Know dma state in the driver hot path.
2824 	 */
2825 	chan->idle = true;
2826 
2827 	spin_lock_init(&chan->lock);
2828 	INIT_LIST_HEAD(&chan->pending_list);
2829 	INIT_LIST_HEAD(&chan->done_list);
2830 	INIT_LIST_HEAD(&chan->active_list);
2831 	INIT_LIST_HEAD(&chan->free_seg_list);
2832 
2833 	/* Retrieve the channel properties from the device tree */
2834 	has_dre = of_property_read_bool(node, "xlnx,include-dre");
2835 
2836 	chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode");
2837 
2838 	err = of_property_read_u32(node, "xlnx,datawidth", &value);
2839 	if (err) {
2840 		dev_err(xdev->dev, "missing xlnx,datawidth property\n");
2841 		return err;
2842 	}
2843 	width = value >> 3; /* Convert bits to bytes */
2844 
2845 	/* If data width is greater than 8 bytes, DRE is not in hw */
2846 	if (width > 8)
2847 		has_dre = false;
2848 
2849 	if (!has_dre)
2850 		xdev->common.copy_align = (enum dmaengine_alignment)fls(width - 1);
2851 
2852 	if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel") ||
2853 	    of_device_is_compatible(node, "xlnx,axi-dma-mm2s-channel") ||
2854 	    of_device_is_compatible(node, "xlnx,axi-cdma-channel")) {
2855 		chan->direction = DMA_MEM_TO_DEV;
2856 		chan->id = xdev->mm2s_chan_id++;
2857 		chan->tdest = chan->id;
2858 
2859 		chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
2860 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2861 			chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET;
2862 			chan->config.park = 1;
2863 
2864 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2865 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_MM2S)
2866 				chan->flush_on_fsync = true;
2867 		}
2868 	} else if (of_device_is_compatible(node,
2869 					   "xlnx,axi-vdma-s2mm-channel") ||
2870 		   of_device_is_compatible(node,
2871 					   "xlnx,axi-dma-s2mm-channel")) {
2872 		chan->direction = DMA_DEV_TO_MEM;
2873 		chan->id = xdev->s2mm_chan_id++;
2874 		chan->tdest = chan->id - xdev->dma_config->max_channels / 2;
2875 		chan->has_vflip = of_property_read_bool(node,
2876 					"xlnx,enable-vert-flip");
2877 		if (chan->has_vflip) {
2878 			chan->config.vflip_en = dma_read(chan,
2879 				XILINX_VDMA_REG_ENABLE_VERTICAL_FLIP) &
2880 				XILINX_VDMA_ENABLE_VERTICAL_FLIP;
2881 		}
2882 
2883 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
2884 			chan->ctrl_offset = XILINX_MCDMA_S2MM_CTRL_OFFSET;
2885 		else
2886 			chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
2887 
2888 		if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
2889 			chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET;
2890 			chan->config.park = 1;
2891 
2892 			if (xdev->flush_on_fsync == XILINX_DMA_FLUSH_BOTH ||
2893 			    xdev->flush_on_fsync == XILINX_DMA_FLUSH_S2MM)
2894 				chan->flush_on_fsync = true;
2895 		}
2896 	} else {
2897 		dev_err(xdev->dev, "Invalid channel compatible node\n");
2898 		return -EINVAL;
2899 	}
2900 
2901 	/* Request the interrupt */
2902 	chan->irq = of_irq_get(node, chan->tdest);
2903 	if (chan->irq < 0)
2904 		return dev_err_probe(xdev->dev, chan->irq, "failed to get irq\n");
2905 	err = request_irq(chan->irq, xdev->dma_config->irq_handler,
2906 			  IRQF_SHARED, "xilinx-dma-controller", chan);
2907 	if (err) {
2908 		dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq);
2909 		return err;
2910 	}
2911 
2912 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
2913 		chan->start_transfer = xilinx_dma_start_transfer;
2914 		chan->stop_transfer = xilinx_dma_stop_transfer;
2915 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
2916 		chan->start_transfer = xilinx_mcdma_start_transfer;
2917 		chan->stop_transfer = xilinx_dma_stop_transfer;
2918 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
2919 		chan->start_transfer = xilinx_cdma_start_transfer;
2920 		chan->stop_transfer = xilinx_cdma_stop_transfer;
2921 	} else {
2922 		chan->start_transfer = xilinx_vdma_start_transfer;
2923 		chan->stop_transfer = xilinx_dma_stop_transfer;
2924 	}
2925 
2926 	/* check if SG is enabled (only for AXIDMA, AXIMCDMA, and CDMA) */
2927 	if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) {
2928 		if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA ||
2929 		    dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) &
2930 			    XILINX_DMA_DMASR_SG_MASK)
2931 			chan->has_sg = true;
2932 		dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id,
2933 			chan->has_sg ? "enabled" : "disabled");
2934 	}
2935 
2936 	/* Initialize the tasklet */
2937 	tasklet_setup(&chan->tasklet, xilinx_dma_do_tasklet);
2938 
2939 	/*
2940 	 * Initialize the DMA channel and add it to the DMA engine channels
2941 	 * list.
2942 	 */
2943 	chan->common.device = &xdev->common;
2944 
2945 	list_add_tail(&chan->common.device_node, &xdev->common.channels);
2946 	xdev->chan[chan->id] = chan;
2947 
2948 	/* Reset the channel */
2949 	err = xilinx_dma_chan_reset(chan);
2950 	if (err < 0) {
2951 		dev_err(xdev->dev, "Reset channel failed\n");
2952 		return err;
2953 	}
2954 
2955 	return 0;
2956 }
2957 
2958 /**
2959  * xilinx_dma_child_probe - Per child node probe
2960  * It get number of dma-channels per child node from
2961  * device-tree and initializes all the channels.
2962  *
2963  * @xdev: Driver specific device structure
2964  * @node: Device node
2965  *
2966  * Return: '0' on success and failure value on error.
2967  */
2968 static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
2969 				    struct device_node *node)
2970 {
2971 	int ret, i;
2972 	u32 nr_channels = 1;
2973 
2974 	ret = of_property_read_u32(node, "dma-channels", &nr_channels);
2975 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA && ret < 0)
2976 		dev_warn(xdev->dev, "missing dma-channels property\n");
2977 
2978 	for (i = 0; i < nr_channels; i++) {
2979 		ret = xilinx_dma_chan_probe(xdev, node);
2980 		if (ret)
2981 			return ret;
2982 	}
2983 
2984 	return 0;
2985 }
2986 
2987 /**
2988  * of_dma_xilinx_xlate - Translation function
2989  * @dma_spec: Pointer to DMA specifier as found in the device tree
2990  * @ofdma: Pointer to DMA controller data
2991  *
2992  * Return: DMA channel pointer on success and NULL on error
2993  */
2994 static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
2995 						struct of_dma *ofdma)
2996 {
2997 	struct xilinx_dma_device *xdev = ofdma->of_dma_data;
2998 	int chan_id = dma_spec->args[0];
2999 
3000 	if (chan_id >= xdev->dma_config->max_channels || !xdev->chan[chan_id])
3001 		return NULL;
3002 
3003 	return dma_get_slave_channel(&xdev->chan[chan_id]->common);
3004 }
3005 
3006 static const struct xilinx_dma_config axidma_config = {
3007 	.dmatype = XDMA_TYPE_AXIDMA,
3008 	.clk_init = axidma_clk_init,
3009 	.irq_handler = xilinx_dma_irq_handler,
3010 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3011 };
3012 
3013 static const struct xilinx_dma_config aximcdma_config = {
3014 	.dmatype = XDMA_TYPE_AXIMCDMA,
3015 	.clk_init = axidma_clk_init,
3016 	.irq_handler = xilinx_mcdma_irq_handler,
3017 	.max_channels = XILINX_MCDMA_MAX_CHANS_PER_DEVICE,
3018 };
3019 static const struct xilinx_dma_config axicdma_config = {
3020 	.dmatype = XDMA_TYPE_CDMA,
3021 	.clk_init = axicdma_clk_init,
3022 	.irq_handler = xilinx_dma_irq_handler,
3023 	.max_channels = XILINX_CDMA_MAX_CHANS_PER_DEVICE,
3024 };
3025 
3026 static const struct xilinx_dma_config axivdma_config = {
3027 	.dmatype = XDMA_TYPE_VDMA,
3028 	.clk_init = axivdma_clk_init,
3029 	.irq_handler = xilinx_dma_irq_handler,
3030 	.max_channels = XILINX_DMA_MAX_CHANS_PER_DEVICE,
3031 };
3032 
3033 static const struct of_device_id xilinx_dma_of_ids[] = {
3034 	{ .compatible = "xlnx,axi-dma-1.00.a", .data = &axidma_config },
3035 	{ .compatible = "xlnx,axi-cdma-1.00.a", .data = &axicdma_config },
3036 	{ .compatible = "xlnx,axi-vdma-1.00.a", .data = &axivdma_config },
3037 	{ .compatible = "xlnx,axi-mcdma-1.00.a", .data = &aximcdma_config },
3038 	{}
3039 };
3040 MODULE_DEVICE_TABLE(of, xilinx_dma_of_ids);
3041 
3042 /**
3043  * xilinx_dma_probe - Driver probe function
3044  * @pdev: Pointer to the platform_device structure
3045  *
3046  * Return: '0' on success and failure value on error
3047  */
3048 static int xilinx_dma_probe(struct platform_device *pdev)
3049 {
3050 	int (*clk_init)(struct platform_device *, struct clk **, struct clk **,
3051 			struct clk **, struct clk **, struct clk **)
3052 					= axivdma_clk_init;
3053 	struct device_node *node = pdev->dev.of_node;
3054 	struct xilinx_dma_device *xdev;
3055 	struct device_node *child, *np = pdev->dev.of_node;
3056 	u32 num_frames, addr_width, len_width;
3057 	int i, err;
3058 
3059 	/* Allocate and initialize the DMA engine structure */
3060 	xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL);
3061 	if (!xdev)
3062 		return -ENOMEM;
3063 
3064 	xdev->dev = &pdev->dev;
3065 	if (np) {
3066 		const struct of_device_id *match;
3067 
3068 		match = of_match_node(xilinx_dma_of_ids, np);
3069 		if (match && match->data) {
3070 			xdev->dma_config = match->data;
3071 			clk_init = xdev->dma_config->clk_init;
3072 		}
3073 	}
3074 
3075 	err = clk_init(pdev, &xdev->axi_clk, &xdev->tx_clk, &xdev->txs_clk,
3076 		       &xdev->rx_clk, &xdev->rxs_clk);
3077 	if (err)
3078 		return err;
3079 
3080 	/* Request and map I/O memory */
3081 	xdev->regs = devm_platform_ioremap_resource(pdev, 0);
3082 	if (IS_ERR(xdev->regs)) {
3083 		err = PTR_ERR(xdev->regs);
3084 		goto disable_clks;
3085 	}
3086 	/* Retrieve the DMA engine properties from the device tree */
3087 	xdev->max_buffer_len = GENMASK(XILINX_DMA_MAX_TRANS_LEN_MAX - 1, 0);
3088 	xdev->s2mm_chan_id = xdev->dma_config->max_channels / 2;
3089 
3090 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA ||
3091 	    xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3092 		if (!of_property_read_u32(node, "xlnx,sg-length-width",
3093 					  &len_width)) {
3094 			if (len_width < XILINX_DMA_MAX_TRANS_LEN_MIN ||
3095 			    len_width > XILINX_DMA_V2_MAX_TRANS_LEN_MAX) {
3096 				dev_warn(xdev->dev,
3097 					 "invalid xlnx,sg-length-width property value. Using default width\n");
3098 			} else {
3099 				if (len_width > XILINX_DMA_MAX_TRANS_LEN_MAX)
3100 					dev_warn(xdev->dev, "Please ensure that IP supports buffer length > 23 bits\n");
3101 				xdev->max_buffer_len =
3102 					GENMASK(len_width - 1, 0);
3103 			}
3104 		}
3105 	}
3106 
3107 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3108 		xdev->has_axistream_connected =
3109 			of_property_read_bool(node, "xlnx,axistream-connected");
3110 	}
3111 
3112 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3113 		err = of_property_read_u32(node, "xlnx,num-fstores",
3114 					   &num_frames);
3115 		if (err < 0) {
3116 			dev_err(xdev->dev,
3117 				"missing xlnx,num-fstores property\n");
3118 			goto disable_clks;
3119 		}
3120 
3121 		err = of_property_read_u32(node, "xlnx,flush-fsync",
3122 					   &xdev->flush_on_fsync);
3123 		if (err < 0)
3124 			dev_warn(xdev->dev,
3125 				 "missing xlnx,flush-fsync property\n");
3126 	}
3127 
3128 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
3129 	if (err < 0)
3130 		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
3131 
3132 	if (addr_width > 32)
3133 		xdev->ext_addr = true;
3134 	else
3135 		xdev->ext_addr = false;
3136 
3137 	/* Set metadata mode */
3138 	if (xdev->has_axistream_connected)
3139 		xdev->common.desc_metadata_modes = DESC_METADATA_ENGINE;
3140 
3141 	/* Set the dma mask bits */
3142 	err = dma_set_mask_and_coherent(xdev->dev, DMA_BIT_MASK(addr_width));
3143 	if (err < 0) {
3144 		dev_err(xdev->dev, "DMA mask error %d\n", err);
3145 		goto disable_clks;
3146 	}
3147 
3148 	/* Initialize the DMA engine */
3149 	xdev->common.dev = &pdev->dev;
3150 
3151 	INIT_LIST_HEAD(&xdev->common.channels);
3152 	if (!(xdev->dma_config->dmatype == XDMA_TYPE_CDMA)) {
3153 		dma_cap_set(DMA_SLAVE, xdev->common.cap_mask);
3154 		dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
3155 	}
3156 
3157 	xdev->common.device_alloc_chan_resources =
3158 				xilinx_dma_alloc_chan_resources;
3159 	xdev->common.device_free_chan_resources =
3160 				xilinx_dma_free_chan_resources;
3161 	xdev->common.device_terminate_all = xilinx_dma_terminate_all;
3162 	xdev->common.device_synchronize = xilinx_dma_synchronize;
3163 	xdev->common.device_tx_status = xilinx_dma_tx_status;
3164 	xdev->common.device_issue_pending = xilinx_dma_issue_pending;
3165 	xdev->common.device_config = xilinx_dma_device_config;
3166 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
3167 		dma_cap_set(DMA_CYCLIC, xdev->common.cap_mask);
3168 		xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
3169 		xdev->common.device_prep_dma_cyclic =
3170 					  xilinx_dma_prep_dma_cyclic;
3171 		/* Residue calculation is supported by only AXI DMA and CDMA */
3172 		xdev->common.residue_granularity =
3173 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3174 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
3175 		dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
3176 		xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
3177 		/* Residue calculation is supported by only AXI DMA and CDMA */
3178 		xdev->common.residue_granularity =
3179 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
3180 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA) {
3181 		xdev->common.device_prep_slave_sg = xilinx_mcdma_prep_slave_sg;
3182 	} else {
3183 		xdev->common.device_prep_interleaved_dma =
3184 				xilinx_vdma_dma_prep_interleaved;
3185 	}
3186 
3187 	platform_set_drvdata(pdev, xdev);
3188 
3189 	/* Initialize the channels */
3190 	for_each_child_of_node(node, child) {
3191 		err = xilinx_dma_child_probe(xdev, child);
3192 		if (err < 0) {
3193 			of_node_put(child);
3194 			goto error;
3195 		}
3196 	}
3197 
3198 	if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
3199 		for (i = 0; i < xdev->dma_config->max_channels; i++)
3200 			if (xdev->chan[i])
3201 				xdev->chan[i]->num_frms = num_frames;
3202 	}
3203 
3204 	/* Register the DMA engine with the core */
3205 	err = dma_async_device_register(&xdev->common);
3206 	if (err) {
3207 		dev_err(xdev->dev, "failed to register the dma device\n");
3208 		goto error;
3209 	}
3210 
3211 	err = of_dma_controller_register(node, of_dma_xilinx_xlate,
3212 					 xdev);
3213 	if (err < 0) {
3214 		dev_err(&pdev->dev, "Unable to register DMA to DT\n");
3215 		dma_async_device_unregister(&xdev->common);
3216 		goto error;
3217 	}
3218 
3219 	if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
3220 		dev_info(&pdev->dev, "Xilinx AXI DMA Engine Driver Probed!!\n");
3221 	else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA)
3222 		dev_info(&pdev->dev, "Xilinx AXI CDMA Engine Driver Probed!!\n");
3223 	else if (xdev->dma_config->dmatype == XDMA_TYPE_AXIMCDMA)
3224 		dev_info(&pdev->dev, "Xilinx AXI MCDMA Engine Driver Probed!!\n");
3225 	else
3226 		dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n");
3227 
3228 	return 0;
3229 
3230 error:
3231 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3232 		if (xdev->chan[i])
3233 			xilinx_dma_chan_remove(xdev->chan[i]);
3234 disable_clks:
3235 	xdma_disable_allclks(xdev);
3236 
3237 	return err;
3238 }
3239 
3240 /**
3241  * xilinx_dma_remove - Driver remove function
3242  * @pdev: Pointer to the platform_device structure
3243  *
3244  * Return: Always '0'
3245  */
3246 static int xilinx_dma_remove(struct platform_device *pdev)
3247 {
3248 	struct xilinx_dma_device *xdev = platform_get_drvdata(pdev);
3249 	int i;
3250 
3251 	of_dma_controller_free(pdev->dev.of_node);
3252 
3253 	dma_async_device_unregister(&xdev->common);
3254 
3255 	for (i = 0; i < xdev->dma_config->max_channels; i++)
3256 		if (xdev->chan[i])
3257 			xilinx_dma_chan_remove(xdev->chan[i]);
3258 
3259 	xdma_disable_allclks(xdev);
3260 
3261 	return 0;
3262 }
3263 
3264 static struct platform_driver xilinx_vdma_driver = {
3265 	.driver = {
3266 		.name = "xilinx-vdma",
3267 		.of_match_table = xilinx_dma_of_ids,
3268 	},
3269 	.probe = xilinx_dma_probe,
3270 	.remove = xilinx_dma_remove,
3271 };
3272 
3273 module_platform_driver(xilinx_vdma_driver);
3274 
3275 MODULE_AUTHOR("Xilinx, Inc.");
3276 MODULE_DESCRIPTION("Xilinx VDMA driver");
3277 MODULE_LICENSE("GPL v2");
3278