xref: /openbmc/linux/drivers/dma/xgene-dma.c (revision 9cfc5c90)
1 /*
2  * Applied Micro X-Gene SoC DMA engine Driver
3  *
4  * Copyright (c) 2015, Applied Micro Circuits Corporation
5  * Authors: Rameshwar Prasad Sahu <rsahu@apm.com>
6  *	    Loc Ho <lho@apm.com>
7  *
8  * This program is free software; you can redistribute  it and/or modify it
9  * under  the terms of  the GNU General  Public License as published by the
10  * Free Software Foundation;  either version 2 of the  License, or (at your
11  * option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
20  *
21  * NOTE: PM support is currently not available.
22  */
23 
24 #include <linux/acpi.h>
25 #include <linux/clk.h>
26 #include <linux/delay.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/dmaengine.h>
29 #include <linux/dmapool.h>
30 #include <linux/interrupt.h>
31 #include <linux/io.h>
32 #include <linux/module.h>
33 #include <linux/of_device.h>
34 
35 #include "dmaengine.h"
36 
37 /* X-Gene DMA ring csr registers and bit definations */
38 #define XGENE_DMA_RING_CONFIG			0x04
39 #define XGENE_DMA_RING_ENABLE			BIT(31)
40 #define XGENE_DMA_RING_ID			0x08
41 #define XGENE_DMA_RING_ID_SETUP(v)		((v) | BIT(31))
42 #define XGENE_DMA_RING_ID_BUF			0x0C
43 #define XGENE_DMA_RING_ID_BUF_SETUP(v)		(((v) << 9) | BIT(21))
44 #define XGENE_DMA_RING_THRESLD0_SET1		0x30
45 #define XGENE_DMA_RING_THRESLD0_SET1_VAL	0X64
46 #define XGENE_DMA_RING_THRESLD1_SET1		0x34
47 #define XGENE_DMA_RING_THRESLD1_SET1_VAL	0xC8
48 #define XGENE_DMA_RING_HYSTERESIS		0x68
49 #define XGENE_DMA_RING_HYSTERESIS_VAL		0xFFFFFFFF
50 #define XGENE_DMA_RING_STATE			0x6C
51 #define XGENE_DMA_RING_STATE_WR_BASE		0x70
52 #define XGENE_DMA_RING_NE_INT_MODE		0x017C
53 #define XGENE_DMA_RING_NE_INT_MODE_SET(m, v)	\
54 	((m) = ((m) & ~BIT(31 - (v))) | BIT(31 - (v)))
55 #define XGENE_DMA_RING_NE_INT_MODE_RESET(m, v)	\
56 	((m) &= (~BIT(31 - (v))))
57 #define XGENE_DMA_RING_CLKEN			0xC208
58 #define XGENE_DMA_RING_SRST			0xC200
59 #define XGENE_DMA_RING_MEM_RAM_SHUTDOWN		0xD070
60 #define XGENE_DMA_RING_BLK_MEM_RDY		0xD074
61 #define XGENE_DMA_RING_BLK_MEM_RDY_VAL		0xFFFFFFFF
62 #define XGENE_DMA_RING_ID_GET(owner, num)	(((owner) << 6) | (num))
63 #define XGENE_DMA_RING_DST_ID(v)		((1 << 10) | (v))
64 #define XGENE_DMA_RING_CMD_OFFSET		0x2C
65 #define XGENE_DMA_RING_CMD_BASE_OFFSET(v)	((v) << 6)
66 #define XGENE_DMA_RING_COHERENT_SET(m)		\
67 	(((u32 *)(m))[2] |= BIT(4))
68 #define XGENE_DMA_RING_ADDRL_SET(m, v)		\
69 	(((u32 *)(m))[2] |= (((v) >> 8) << 5))
70 #define XGENE_DMA_RING_ADDRH_SET(m, v)		\
71 	(((u32 *)(m))[3] |= ((v) >> 35))
72 #define XGENE_DMA_RING_ACCEPTLERR_SET(m)	\
73 	(((u32 *)(m))[3] |= BIT(19))
74 #define XGENE_DMA_RING_SIZE_SET(m, v)		\
75 	(((u32 *)(m))[3] |= ((v) << 23))
76 #define XGENE_DMA_RING_RECOMBBUF_SET(m)		\
77 	(((u32 *)(m))[3] |= BIT(27))
78 #define XGENE_DMA_RING_RECOMTIMEOUTL_SET(m)	\
79 	(((u32 *)(m))[3] |= (0x7 << 28))
80 #define XGENE_DMA_RING_RECOMTIMEOUTH_SET(m)	\
81 	(((u32 *)(m))[4] |= 0x3)
82 #define XGENE_DMA_RING_SELTHRSH_SET(m)		\
83 	(((u32 *)(m))[4] |= BIT(3))
84 #define XGENE_DMA_RING_TYPE_SET(m, v)		\
85 	(((u32 *)(m))[4] |= ((v) << 19))
86 
87 /* X-Gene DMA device csr registers and bit definitions */
88 #define XGENE_DMA_IPBRR				0x0
89 #define XGENE_DMA_DEV_ID_RD(v)			((v) & 0x00000FFF)
90 #define XGENE_DMA_BUS_ID_RD(v)			(((v) >> 12) & 3)
91 #define XGENE_DMA_REV_NO_RD(v)			(((v) >> 14) & 3)
92 #define XGENE_DMA_GCR				0x10
93 #define XGENE_DMA_CH_SETUP(v)			\
94 	((v) = ((v) & ~0x000FFFFF) | 0x000AAFFF)
95 #define XGENE_DMA_ENABLE(v)			((v) |= BIT(31))
96 #define XGENE_DMA_DISABLE(v)			((v) &= ~BIT(31))
97 #define XGENE_DMA_RAID6_CONT			0x14
98 #define XGENE_DMA_RAID6_MULTI_CTRL(v)		((v) << 24)
99 #define XGENE_DMA_INT				0x70
100 #define XGENE_DMA_INT_MASK			0x74
101 #define XGENE_DMA_INT_ALL_MASK			0xFFFFFFFF
102 #define XGENE_DMA_INT_ALL_UNMASK		0x0
103 #define XGENE_DMA_INT_MASK_SHIFT		0x14
104 #define XGENE_DMA_RING_INT0_MASK		0x90A0
105 #define XGENE_DMA_RING_INT1_MASK		0x90A8
106 #define XGENE_DMA_RING_INT2_MASK		0x90B0
107 #define XGENE_DMA_RING_INT3_MASK		0x90B8
108 #define XGENE_DMA_RING_INT4_MASK		0x90C0
109 #define XGENE_DMA_CFG_RING_WQ_ASSOC		0x90E0
110 #define XGENE_DMA_ASSOC_RING_MNGR1		0xFFFFFFFF
111 #define XGENE_DMA_MEM_RAM_SHUTDOWN		0xD070
112 #define XGENE_DMA_BLK_MEM_RDY			0xD074
113 #define XGENE_DMA_BLK_MEM_RDY_VAL		0xFFFFFFFF
114 #define XGENE_DMA_RING_CMD_SM_OFFSET		0x8000
115 
116 /* X-Gene SoC EFUSE csr register and bit defination */
117 #define XGENE_SOC_JTAG1_SHADOW			0x18
118 #define XGENE_DMA_PQ_DISABLE_MASK		BIT(13)
119 
120 /* X-Gene DMA Descriptor format */
121 #define XGENE_DMA_DESC_NV_BIT			BIT_ULL(50)
122 #define XGENE_DMA_DESC_IN_BIT			BIT_ULL(55)
123 #define XGENE_DMA_DESC_C_BIT			BIT_ULL(63)
124 #define XGENE_DMA_DESC_DR_BIT			BIT_ULL(61)
125 #define XGENE_DMA_DESC_ELERR_POS		46
126 #define XGENE_DMA_DESC_RTYPE_POS		56
127 #define XGENE_DMA_DESC_LERR_POS			60
128 #define XGENE_DMA_DESC_BUFLEN_POS		48
129 #define XGENE_DMA_DESC_HOENQ_NUM_POS		48
130 #define XGENE_DMA_DESC_ELERR_RD(m)		\
131 	(((m) >> XGENE_DMA_DESC_ELERR_POS) & 0x3)
132 #define XGENE_DMA_DESC_LERR_RD(m)		\
133 	(((m) >> XGENE_DMA_DESC_LERR_POS) & 0x7)
134 #define XGENE_DMA_DESC_STATUS(elerr, lerr)	\
135 	(((elerr) << 4) | (lerr))
136 
137 /* X-Gene DMA descriptor empty s/w signature */
138 #define XGENE_DMA_DESC_EMPTY_SIGNATURE		~0ULL
139 
140 /* X-Gene DMA configurable parameters defines */
141 #define XGENE_DMA_RING_NUM		512
142 #define XGENE_DMA_BUFNUM		0x0
143 #define XGENE_DMA_CPU_BUFNUM		0x18
144 #define XGENE_DMA_RING_OWNER_DMA	0x03
145 #define XGENE_DMA_RING_OWNER_CPU	0x0F
146 #define XGENE_DMA_RING_TYPE_REGULAR	0x01
147 #define XGENE_DMA_RING_WQ_DESC_SIZE	32	/* 32 Bytes */
148 #define XGENE_DMA_RING_NUM_CONFIG	5
149 #define XGENE_DMA_MAX_CHANNEL		4
150 #define XGENE_DMA_XOR_CHANNEL		0
151 #define XGENE_DMA_PQ_CHANNEL		1
152 #define XGENE_DMA_MAX_BYTE_CNT		0x4000	/* 16 KB */
153 #define XGENE_DMA_MAX_64B_DESC_BYTE_CNT	0x14000	/* 80 KB */
154 #define XGENE_DMA_MAX_XOR_SRC		5
155 #define XGENE_DMA_16K_BUFFER_LEN_CODE	0x0
156 #define XGENE_DMA_INVALID_LEN_CODE	0x7800000000000000ULL
157 
158 /* X-Gene DMA descriptor error codes */
159 #define ERR_DESC_AXI			0x01
160 #define ERR_BAD_DESC			0x02
161 #define ERR_READ_DATA_AXI		0x03
162 #define ERR_WRITE_DATA_AXI		0x04
163 #define ERR_FBP_TIMEOUT			0x05
164 #define ERR_ECC				0x06
165 #define ERR_DIFF_SIZE			0x08
166 #define ERR_SCT_GAT_LEN			0x09
167 #define ERR_CRC_ERR			0x11
168 #define ERR_CHKSUM			0x12
169 #define ERR_DIF				0x13
170 
171 /* X-Gene DMA error interrupt codes */
172 #define ERR_DIF_SIZE_INT		0x0
173 #define ERR_GS_ERR_INT			0x1
174 #define ERR_FPB_TIMEO_INT		0x2
175 #define ERR_WFIFO_OVF_INT		0x3
176 #define ERR_RFIFO_OVF_INT		0x4
177 #define ERR_WR_TIMEO_INT		0x5
178 #define ERR_RD_TIMEO_INT		0x6
179 #define ERR_WR_ERR_INT			0x7
180 #define ERR_RD_ERR_INT			0x8
181 #define ERR_BAD_DESC_INT		0x9
182 #define ERR_DESC_DST_INT		0xA
183 #define ERR_DESC_SRC_INT		0xB
184 
185 /* X-Gene DMA flyby operation code */
186 #define FLYBY_2SRC_XOR			0x80
187 #define FLYBY_3SRC_XOR			0x90
188 #define FLYBY_4SRC_XOR			0xA0
189 #define FLYBY_5SRC_XOR			0xB0
190 
191 /* X-Gene DMA SW descriptor flags */
192 #define XGENE_DMA_FLAG_64B_DESC		BIT(0)
193 
194 /* Define to dump X-Gene DMA descriptor */
195 #define XGENE_DMA_DESC_DUMP(desc, m)	\
196 	print_hex_dump(KERN_ERR, (m),	\
197 			DUMP_PREFIX_ADDRESS, 16, 8, (desc), 32, 0)
198 
199 #define to_dma_desc_sw(tx)		\
200 	container_of(tx, struct xgene_dma_desc_sw, tx)
201 #define to_dma_chan(dchan)		\
202 	container_of(dchan, struct xgene_dma_chan, dma_chan)
203 
204 #define chan_dbg(chan, fmt, arg...)	\
205 	dev_dbg(chan->dev, "%s: " fmt, chan->name, ##arg)
206 #define chan_err(chan, fmt, arg...)	\
207 	dev_err(chan->dev, "%s: " fmt, chan->name, ##arg)
208 
209 struct xgene_dma_desc_hw {
210 	__le64 m0;
211 	__le64 m1;
212 	__le64 m2;
213 	__le64 m3;
214 };
215 
216 enum xgene_dma_ring_cfgsize {
217 	XGENE_DMA_RING_CFG_SIZE_512B,
218 	XGENE_DMA_RING_CFG_SIZE_2KB,
219 	XGENE_DMA_RING_CFG_SIZE_16KB,
220 	XGENE_DMA_RING_CFG_SIZE_64KB,
221 	XGENE_DMA_RING_CFG_SIZE_512KB,
222 	XGENE_DMA_RING_CFG_SIZE_INVALID
223 };
224 
225 struct xgene_dma_ring {
226 	struct xgene_dma *pdma;
227 	u8 buf_num;
228 	u16 id;
229 	u16 num;
230 	u16 head;
231 	u16 owner;
232 	u16 slots;
233 	u16 dst_ring_num;
234 	u32 size;
235 	void __iomem *cmd;
236 	void __iomem *cmd_base;
237 	dma_addr_t desc_paddr;
238 	u32 state[XGENE_DMA_RING_NUM_CONFIG];
239 	enum xgene_dma_ring_cfgsize cfgsize;
240 	union {
241 		void *desc_vaddr;
242 		struct xgene_dma_desc_hw *desc_hw;
243 	};
244 };
245 
246 struct xgene_dma_desc_sw {
247 	struct xgene_dma_desc_hw desc1;
248 	struct xgene_dma_desc_hw desc2;
249 	u32 flags;
250 	struct list_head node;
251 	struct list_head tx_list;
252 	struct dma_async_tx_descriptor tx;
253 };
254 
255 /**
256  * struct xgene_dma_chan - internal representation of an X-Gene DMA channel
257  * @dma_chan: dmaengine channel object member
258  * @pdma: X-Gene DMA device structure reference
259  * @dev: struct device reference for dma mapping api
260  * @id: raw id of this channel
261  * @rx_irq: channel IRQ
262  * @name: name of X-Gene DMA channel
263  * @lock: serializes enqueue/dequeue operations to the descriptor pool
264  * @pending: number of transaction request pushed to DMA controller for
265  *	execution, but still waiting for completion,
266  * @max_outstanding: max number of outstanding request we can push to channel
267  * @ld_pending: descriptors which are queued to run, but have not yet been
268  *	submitted to the hardware for execution
269  * @ld_running: descriptors which are currently being executing by the hardware
270  * @ld_completed: descriptors which have finished execution by the hardware.
271  *	These descriptors have already had their cleanup actions run. They
272  *	are waiting for the ACK bit to be set by the async tx API.
273  * @desc_pool: descriptor pool for DMA operations
274  * @tasklet: bottom half where all completed descriptors cleans
275  * @tx_ring: transmit ring descriptor that we use to prepare actual
276  *	descriptors for further executions
277  * @rx_ring: receive ring descriptor that we use to get completed DMA
278  *	descriptors during cleanup time
279  */
280 struct xgene_dma_chan {
281 	struct dma_chan dma_chan;
282 	struct xgene_dma *pdma;
283 	struct device *dev;
284 	int id;
285 	int rx_irq;
286 	char name[10];
287 	spinlock_t lock;
288 	int pending;
289 	int max_outstanding;
290 	struct list_head ld_pending;
291 	struct list_head ld_running;
292 	struct list_head ld_completed;
293 	struct dma_pool *desc_pool;
294 	struct tasklet_struct tasklet;
295 	struct xgene_dma_ring tx_ring;
296 	struct xgene_dma_ring rx_ring;
297 };
298 
299 /**
300  * struct xgene_dma - internal representation of an X-Gene DMA device
301  * @err_irq: DMA error irq number
302  * @ring_num: start id number for DMA ring
303  * @csr_dma: base for DMA register access
304  * @csr_ring: base for DMA ring register access
305  * @csr_ring_cmd: base for DMA ring command register access
306  * @csr_efuse: base for efuse register access
307  * @dma_dev: embedded struct dma_device
308  * @chan: reference to X-Gene DMA channels
309  */
310 struct xgene_dma {
311 	struct device *dev;
312 	struct clk *clk;
313 	int err_irq;
314 	int ring_num;
315 	void __iomem *csr_dma;
316 	void __iomem *csr_ring;
317 	void __iomem *csr_ring_cmd;
318 	void __iomem *csr_efuse;
319 	struct dma_device dma_dev[XGENE_DMA_MAX_CHANNEL];
320 	struct xgene_dma_chan chan[XGENE_DMA_MAX_CHANNEL];
321 };
322 
323 static const char * const xgene_dma_desc_err[] = {
324 	[ERR_DESC_AXI] = "AXI error when reading src/dst link list",
325 	[ERR_BAD_DESC] = "ERR or El_ERR fields not set to zero in desc",
326 	[ERR_READ_DATA_AXI] = "AXI error when reading data",
327 	[ERR_WRITE_DATA_AXI] = "AXI error when writing data",
328 	[ERR_FBP_TIMEOUT] = "Timeout on bufpool fetch",
329 	[ERR_ECC] = "ECC double bit error",
330 	[ERR_DIFF_SIZE] = "Bufpool too small to hold all the DIF result",
331 	[ERR_SCT_GAT_LEN] = "Gather and scatter data length not same",
332 	[ERR_CRC_ERR] = "CRC error",
333 	[ERR_CHKSUM] = "Checksum error",
334 	[ERR_DIF] = "DIF error",
335 };
336 
337 static const char * const xgene_dma_err[] = {
338 	[ERR_DIF_SIZE_INT] = "DIF size error",
339 	[ERR_GS_ERR_INT] = "Gather scatter not same size error",
340 	[ERR_FPB_TIMEO_INT] = "Free pool time out error",
341 	[ERR_WFIFO_OVF_INT] = "Write FIFO over flow error",
342 	[ERR_RFIFO_OVF_INT] = "Read FIFO over flow error",
343 	[ERR_WR_TIMEO_INT] = "Write time out error",
344 	[ERR_RD_TIMEO_INT] = "Read time out error",
345 	[ERR_WR_ERR_INT] = "HBF bus write error",
346 	[ERR_RD_ERR_INT] = "HBF bus read error",
347 	[ERR_BAD_DESC_INT] = "Ring descriptor HE0 not set error",
348 	[ERR_DESC_DST_INT] = "HFB reading dst link address error",
349 	[ERR_DESC_SRC_INT] = "HFB reading src link address error",
350 };
351 
352 static bool is_pq_enabled(struct xgene_dma *pdma)
353 {
354 	u32 val;
355 
356 	val = ioread32(pdma->csr_efuse + XGENE_SOC_JTAG1_SHADOW);
357 	return !(val & XGENE_DMA_PQ_DISABLE_MASK);
358 }
359 
360 static u64 xgene_dma_encode_len(size_t len)
361 {
362 	return (len < XGENE_DMA_MAX_BYTE_CNT) ?
363 		((u64)len << XGENE_DMA_DESC_BUFLEN_POS) :
364 		XGENE_DMA_16K_BUFFER_LEN_CODE;
365 }
366 
367 static u8 xgene_dma_encode_xor_flyby(u32 src_cnt)
368 {
369 	static u8 flyby_type[] = {
370 		FLYBY_2SRC_XOR, /* Dummy */
371 		FLYBY_2SRC_XOR, /* Dummy */
372 		FLYBY_2SRC_XOR,
373 		FLYBY_3SRC_XOR,
374 		FLYBY_4SRC_XOR,
375 		FLYBY_5SRC_XOR
376 	};
377 
378 	return flyby_type[src_cnt];
379 }
380 
381 static void xgene_dma_set_src_buffer(__le64 *ext8, size_t *len,
382 				     dma_addr_t *paddr)
383 {
384 	size_t nbytes = (*len < XGENE_DMA_MAX_BYTE_CNT) ?
385 			*len : XGENE_DMA_MAX_BYTE_CNT;
386 
387 	*ext8 |= cpu_to_le64(*paddr);
388 	*ext8 |= cpu_to_le64(xgene_dma_encode_len(nbytes));
389 	*len -= nbytes;
390 	*paddr += nbytes;
391 }
392 
393 static void xgene_dma_invalidate_buffer(__le64 *ext8)
394 {
395 	*ext8 |= cpu_to_le64(XGENE_DMA_INVALID_LEN_CODE);
396 }
397 
398 static __le64 *xgene_dma_lookup_ext8(struct xgene_dma_desc_hw *desc, int idx)
399 {
400 	switch (idx) {
401 	case 0:
402 		return &desc->m1;
403 	case 1:
404 		return &desc->m0;
405 	case 2:
406 		return &desc->m3;
407 	case 3:
408 		return &desc->m2;
409 	default:
410 		pr_err("Invalid dma descriptor index\n");
411 	}
412 
413 	return NULL;
414 }
415 
416 static void xgene_dma_init_desc(struct xgene_dma_desc_hw *desc,
417 				u16 dst_ring_num)
418 {
419 	desc->m0 |= cpu_to_le64(XGENE_DMA_DESC_IN_BIT);
420 	desc->m0 |= cpu_to_le64((u64)XGENE_DMA_RING_OWNER_DMA <<
421 				XGENE_DMA_DESC_RTYPE_POS);
422 	desc->m1 |= cpu_to_le64(XGENE_DMA_DESC_C_BIT);
423 	desc->m3 |= cpu_to_le64((u64)dst_ring_num <<
424 				XGENE_DMA_DESC_HOENQ_NUM_POS);
425 }
426 
427 static void xgene_dma_prep_cpy_desc(struct xgene_dma_chan *chan,
428 				    struct xgene_dma_desc_sw *desc_sw,
429 				    dma_addr_t dst, dma_addr_t src,
430 				    size_t len)
431 {
432 	struct xgene_dma_desc_hw *desc1, *desc2;
433 	int i;
434 
435 	/* Get 1st descriptor */
436 	desc1 = &desc_sw->desc1;
437 	xgene_dma_init_desc(desc1, chan->tx_ring.dst_ring_num);
438 
439 	/* Set destination address */
440 	desc1->m2 |= cpu_to_le64(XGENE_DMA_DESC_DR_BIT);
441 	desc1->m3 |= cpu_to_le64(dst);
442 
443 	/* Set 1st source address */
444 	xgene_dma_set_src_buffer(&desc1->m1, &len, &src);
445 
446 	if (!len)
447 		return;
448 
449 	/*
450 	 * We need to split this source buffer,
451 	 * and need to use 2nd descriptor
452 	 */
453 	desc2 = &desc_sw->desc2;
454 	desc1->m0 |= cpu_to_le64(XGENE_DMA_DESC_NV_BIT);
455 
456 	/* Set 2nd to 5th source address */
457 	for (i = 0; i < 4 && len; i++)
458 		xgene_dma_set_src_buffer(xgene_dma_lookup_ext8(desc2, i),
459 					 &len, &src);
460 
461 	/* Invalidate unused source address field */
462 	for (; i < 4; i++)
463 		xgene_dma_invalidate_buffer(xgene_dma_lookup_ext8(desc2, i));
464 
465 	/* Updated flag that we have prepared 64B descriptor */
466 	desc_sw->flags |= XGENE_DMA_FLAG_64B_DESC;
467 }
468 
469 static void xgene_dma_prep_xor_desc(struct xgene_dma_chan *chan,
470 				    struct xgene_dma_desc_sw *desc_sw,
471 				    dma_addr_t *dst, dma_addr_t *src,
472 				    u32 src_cnt, size_t *nbytes,
473 				    const u8 *scf)
474 {
475 	struct xgene_dma_desc_hw *desc1, *desc2;
476 	size_t len = *nbytes;
477 	int i;
478 
479 	desc1 = &desc_sw->desc1;
480 	desc2 = &desc_sw->desc2;
481 
482 	/* Initialize DMA descriptor */
483 	xgene_dma_init_desc(desc1, chan->tx_ring.dst_ring_num);
484 
485 	/* Set destination address */
486 	desc1->m2 |= cpu_to_le64(XGENE_DMA_DESC_DR_BIT);
487 	desc1->m3 |= cpu_to_le64(*dst);
488 
489 	/* We have multiple source addresses, so need to set NV bit*/
490 	desc1->m0 |= cpu_to_le64(XGENE_DMA_DESC_NV_BIT);
491 
492 	/* Set flyby opcode */
493 	desc1->m2 |= cpu_to_le64(xgene_dma_encode_xor_flyby(src_cnt));
494 
495 	/* Set 1st to 5th source addresses */
496 	for (i = 0; i < src_cnt; i++) {
497 		len = *nbytes;
498 		xgene_dma_set_src_buffer((i == 0) ? &desc1->m1 :
499 					 xgene_dma_lookup_ext8(desc2, i - 1),
500 					 &len, &src[i]);
501 		desc1->m2 |= cpu_to_le64((scf[i] << ((i + 1) * 8)));
502 	}
503 
504 	/* Update meta data */
505 	*nbytes = len;
506 	*dst += XGENE_DMA_MAX_BYTE_CNT;
507 
508 	/* We need always 64B descriptor to perform xor or pq operations */
509 	desc_sw->flags |= XGENE_DMA_FLAG_64B_DESC;
510 }
511 
512 static dma_cookie_t xgene_dma_tx_submit(struct dma_async_tx_descriptor *tx)
513 {
514 	struct xgene_dma_desc_sw *desc;
515 	struct xgene_dma_chan *chan;
516 	dma_cookie_t cookie;
517 
518 	if (unlikely(!tx))
519 		return -EINVAL;
520 
521 	chan = to_dma_chan(tx->chan);
522 	desc = to_dma_desc_sw(tx);
523 
524 	spin_lock_bh(&chan->lock);
525 
526 	cookie = dma_cookie_assign(tx);
527 
528 	/* Add this transaction list onto the tail of the pending queue */
529 	list_splice_tail_init(&desc->tx_list, &chan->ld_pending);
530 
531 	spin_unlock_bh(&chan->lock);
532 
533 	return cookie;
534 }
535 
536 static void xgene_dma_clean_descriptor(struct xgene_dma_chan *chan,
537 				       struct xgene_dma_desc_sw *desc)
538 {
539 	list_del(&desc->node);
540 	chan_dbg(chan, "LD %p free\n", desc);
541 	dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
542 }
543 
544 static struct xgene_dma_desc_sw *xgene_dma_alloc_descriptor(
545 				 struct xgene_dma_chan *chan)
546 {
547 	struct xgene_dma_desc_sw *desc;
548 	dma_addr_t phys;
549 
550 	desc = dma_pool_zalloc(chan->desc_pool, GFP_NOWAIT, &phys);
551 	if (!desc) {
552 		chan_err(chan, "Failed to allocate LDs\n");
553 		return NULL;
554 	}
555 
556 	INIT_LIST_HEAD(&desc->tx_list);
557 	desc->tx.phys = phys;
558 	desc->tx.tx_submit = xgene_dma_tx_submit;
559 	dma_async_tx_descriptor_init(&desc->tx, &chan->dma_chan);
560 
561 	chan_dbg(chan, "LD %p allocated\n", desc);
562 
563 	return desc;
564 }
565 
566 /**
567  * xgene_dma_clean_completed_descriptor - free all descriptors which
568  * has been completed and acked
569  * @chan: X-Gene DMA channel
570  *
571  * This function is used on all completed and acked descriptors.
572  */
573 static void xgene_dma_clean_completed_descriptor(struct xgene_dma_chan *chan)
574 {
575 	struct xgene_dma_desc_sw *desc, *_desc;
576 
577 	/* Run the callback for each descriptor, in order */
578 	list_for_each_entry_safe(desc, _desc, &chan->ld_completed, node) {
579 		if (async_tx_test_ack(&desc->tx))
580 			xgene_dma_clean_descriptor(chan, desc);
581 	}
582 }
583 
584 /**
585  * xgene_dma_run_tx_complete_actions - cleanup a single link descriptor
586  * @chan: X-Gene DMA channel
587  * @desc: descriptor to cleanup and free
588  *
589  * This function is used on a descriptor which has been executed by the DMA
590  * controller. It will run any callbacks, submit any dependencies.
591  */
592 static void xgene_dma_run_tx_complete_actions(struct xgene_dma_chan *chan,
593 					      struct xgene_dma_desc_sw *desc)
594 {
595 	struct dma_async_tx_descriptor *tx = &desc->tx;
596 
597 	/*
598 	 * If this is not the last transaction in the group,
599 	 * then no need to complete cookie and run any callback as
600 	 * this is not the tx_descriptor which had been sent to caller
601 	 * of this DMA request
602 	 */
603 
604 	if (tx->cookie == 0)
605 		return;
606 
607 	dma_cookie_complete(tx);
608 
609 	/* Run the link descriptor callback function */
610 	if (tx->callback)
611 		tx->callback(tx->callback_param);
612 
613 	dma_descriptor_unmap(tx);
614 
615 	/* Run any dependencies */
616 	dma_run_dependencies(tx);
617 }
618 
619 /**
620  * xgene_dma_clean_running_descriptor - move the completed descriptor from
621  * ld_running to ld_completed
622  * @chan: X-Gene DMA channel
623  * @desc: the descriptor which is completed
624  *
625  * Free the descriptor directly if acked by async_tx api,
626  * else move it to queue ld_completed.
627  */
628 static void xgene_dma_clean_running_descriptor(struct xgene_dma_chan *chan,
629 					       struct xgene_dma_desc_sw *desc)
630 {
631 	/* Remove from the list of running transactions */
632 	list_del(&desc->node);
633 
634 	/*
635 	 * the client is allowed to attach dependent operations
636 	 * until 'ack' is set
637 	 */
638 	if (!async_tx_test_ack(&desc->tx)) {
639 		/*
640 		 * Move this descriptor to the list of descriptors which is
641 		 * completed, but still awaiting the 'ack' bit to be set.
642 		 */
643 		list_add_tail(&desc->node, &chan->ld_completed);
644 		return;
645 	}
646 
647 	chan_dbg(chan, "LD %p free\n", desc);
648 	dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
649 }
650 
651 static void xgene_chan_xfer_request(struct xgene_dma_chan *chan,
652 				    struct xgene_dma_desc_sw *desc_sw)
653 {
654 	struct xgene_dma_ring *ring = &chan->tx_ring;
655 	struct xgene_dma_desc_hw *desc_hw;
656 
657 	/* Get hw descriptor from DMA tx ring */
658 	desc_hw = &ring->desc_hw[ring->head];
659 
660 	/*
661 	 * Increment the head count to point next
662 	 * descriptor for next time
663 	 */
664 	if (++ring->head == ring->slots)
665 		ring->head = 0;
666 
667 	/* Copy prepared sw descriptor data to hw descriptor */
668 	memcpy(desc_hw, &desc_sw->desc1, sizeof(*desc_hw));
669 
670 	/*
671 	 * Check if we have prepared 64B descriptor,
672 	 * in this case we need one more hw descriptor
673 	 */
674 	if (desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) {
675 		desc_hw = &ring->desc_hw[ring->head];
676 
677 		if (++ring->head == ring->slots)
678 			ring->head = 0;
679 
680 		memcpy(desc_hw, &desc_sw->desc2, sizeof(*desc_hw));
681 	}
682 
683 	/* Increment the pending transaction count */
684 	chan->pending += ((desc_sw->flags &
685 			  XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
686 
687 	/* Notify the hw that we have descriptor ready for execution */
688 	iowrite32((desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) ?
689 		  2 : 1, ring->cmd);
690 }
691 
692 /**
693  * xgene_chan_xfer_ld_pending - push any pending transactions to hw
694  * @chan : X-Gene DMA channel
695  *
696  * LOCKING: must hold chan->lock
697  */
698 static void xgene_chan_xfer_ld_pending(struct xgene_dma_chan *chan)
699 {
700 	struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
701 
702 	/*
703 	 * If the list of pending descriptors is empty, then we
704 	 * don't need to do any work at all
705 	 */
706 	if (list_empty(&chan->ld_pending)) {
707 		chan_dbg(chan, "No pending LDs\n");
708 		return;
709 	}
710 
711 	/*
712 	 * Move elements from the queue of pending transactions onto the list
713 	 * of running transactions and push it to hw for further executions
714 	 */
715 	list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_pending, node) {
716 		/*
717 		 * Check if have pushed max number of transactions to hw
718 		 * as capable, so let's stop here and will push remaining
719 		 * elements from pening ld queue after completing some
720 		 * descriptors that we have already pushed
721 		 */
722 		if (chan->pending >= chan->max_outstanding)
723 			return;
724 
725 		xgene_chan_xfer_request(chan, desc_sw);
726 
727 		/*
728 		 * Delete this element from ld pending queue and append it to
729 		 * ld running queue
730 		 */
731 		list_move_tail(&desc_sw->node, &chan->ld_running);
732 	}
733 }
734 
735 /**
736  * xgene_dma_cleanup_descriptors - cleanup link descriptors which are completed
737  * and move them to ld_completed to free until flag 'ack' is set
738  * @chan: X-Gene DMA channel
739  *
740  * This function is used on descriptors which have been executed by the DMA
741  * controller. It will run any callbacks, submit any dependencies, then
742  * free these descriptors if flag 'ack' is set.
743  */
744 static void xgene_dma_cleanup_descriptors(struct xgene_dma_chan *chan)
745 {
746 	struct xgene_dma_ring *ring = &chan->rx_ring;
747 	struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
748 	struct xgene_dma_desc_hw *desc_hw;
749 	struct list_head ld_completed;
750 	u8 status;
751 
752 	INIT_LIST_HEAD(&ld_completed);
753 
754 	spin_lock_bh(&chan->lock);
755 
756 	/* Clean already completed and acked descriptors */
757 	xgene_dma_clean_completed_descriptor(chan);
758 
759 	/* Move all completed descriptors to ld completed queue, in order */
760 	list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_running, node) {
761 		/* Get subsequent hw descriptor from DMA rx ring */
762 		desc_hw = &ring->desc_hw[ring->head];
763 
764 		/* Check if this descriptor has been completed */
765 		if (unlikely(le64_to_cpu(desc_hw->m0) ==
766 			     XGENE_DMA_DESC_EMPTY_SIGNATURE))
767 			break;
768 
769 		if (++ring->head == ring->slots)
770 			ring->head = 0;
771 
772 		/* Check if we have any error with DMA transactions */
773 		status = XGENE_DMA_DESC_STATUS(
774 				XGENE_DMA_DESC_ELERR_RD(le64_to_cpu(
775 							desc_hw->m0)),
776 				XGENE_DMA_DESC_LERR_RD(le64_to_cpu(
777 						       desc_hw->m0)));
778 		if (status) {
779 			/* Print the DMA error type */
780 			chan_err(chan, "%s\n", xgene_dma_desc_err[status]);
781 
782 			/*
783 			 * We have DMA transactions error here. Dump DMA Tx
784 			 * and Rx descriptors for this request */
785 			XGENE_DMA_DESC_DUMP(&desc_sw->desc1,
786 					    "X-Gene DMA TX DESC1: ");
787 
788 			if (desc_sw->flags & XGENE_DMA_FLAG_64B_DESC)
789 				XGENE_DMA_DESC_DUMP(&desc_sw->desc2,
790 						    "X-Gene DMA TX DESC2: ");
791 
792 			XGENE_DMA_DESC_DUMP(desc_hw,
793 					    "X-Gene DMA RX ERR DESC: ");
794 		}
795 
796 		/* Notify the hw about this completed descriptor */
797 		iowrite32(-1, ring->cmd);
798 
799 		/* Mark this hw descriptor as processed */
800 		desc_hw->m0 = cpu_to_le64(XGENE_DMA_DESC_EMPTY_SIGNATURE);
801 
802 		/*
803 		 * Decrement the pending transaction count
804 		 * as we have processed one
805 		 */
806 		chan->pending -= ((desc_sw->flags &
807 				  XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
808 
809 		/*
810 		 * Delete this node from ld running queue and append it to
811 		 * ld completed queue for further processing
812 		 */
813 		list_move_tail(&desc_sw->node, &ld_completed);
814 	}
815 
816 	/*
817 	 * Start any pending transactions automatically
818 	 * In the ideal case, we keep the DMA controller busy while we go
819 	 * ahead and free the descriptors below.
820 	 */
821 	xgene_chan_xfer_ld_pending(chan);
822 
823 	spin_unlock_bh(&chan->lock);
824 
825 	/* Run the callback for each descriptor, in order */
826 	list_for_each_entry_safe(desc_sw, _desc_sw, &ld_completed, node) {
827 		xgene_dma_run_tx_complete_actions(chan, desc_sw);
828 		xgene_dma_clean_running_descriptor(chan, desc_sw);
829 	}
830 }
831 
832 static int xgene_dma_alloc_chan_resources(struct dma_chan *dchan)
833 {
834 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
835 
836 	/* Has this channel already been allocated? */
837 	if (chan->desc_pool)
838 		return 1;
839 
840 	chan->desc_pool = dma_pool_create(chan->name, chan->dev,
841 					  sizeof(struct xgene_dma_desc_sw),
842 					  0, 0);
843 	if (!chan->desc_pool) {
844 		chan_err(chan, "Failed to allocate descriptor pool\n");
845 		return -ENOMEM;
846 	}
847 
848 	chan_dbg(chan, "Allocate descripto pool\n");
849 
850 	return 1;
851 }
852 
853 /**
854  * xgene_dma_free_desc_list - Free all descriptors in a queue
855  * @chan: X-Gene DMA channel
856  * @list: the list to free
857  *
858  * LOCKING: must hold chan->lock
859  */
860 static void xgene_dma_free_desc_list(struct xgene_dma_chan *chan,
861 				     struct list_head *list)
862 {
863 	struct xgene_dma_desc_sw *desc, *_desc;
864 
865 	list_for_each_entry_safe(desc, _desc, list, node)
866 		xgene_dma_clean_descriptor(chan, desc);
867 }
868 
869 static void xgene_dma_free_chan_resources(struct dma_chan *dchan)
870 {
871 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
872 
873 	chan_dbg(chan, "Free all resources\n");
874 
875 	if (!chan->desc_pool)
876 		return;
877 
878 	/* Process all running descriptor */
879 	xgene_dma_cleanup_descriptors(chan);
880 
881 	spin_lock_bh(&chan->lock);
882 
883 	/* Clean all link descriptor queues */
884 	xgene_dma_free_desc_list(chan, &chan->ld_pending);
885 	xgene_dma_free_desc_list(chan, &chan->ld_running);
886 	xgene_dma_free_desc_list(chan, &chan->ld_completed);
887 
888 	spin_unlock_bh(&chan->lock);
889 
890 	/* Delete this channel DMA pool */
891 	dma_pool_destroy(chan->desc_pool);
892 	chan->desc_pool = NULL;
893 }
894 
895 static struct dma_async_tx_descriptor *xgene_dma_prep_sg(
896 	struct dma_chan *dchan, struct scatterlist *dst_sg,
897 	u32 dst_nents, struct scatterlist *src_sg,
898 	u32 src_nents, unsigned long flags)
899 {
900 	struct xgene_dma_desc_sw *first = NULL, *new = NULL;
901 	struct xgene_dma_chan *chan;
902 	size_t dst_avail, src_avail;
903 	dma_addr_t dst, src;
904 	size_t len;
905 
906 	if (unlikely(!dchan))
907 		return NULL;
908 
909 	if (unlikely(!dst_nents || !src_nents))
910 		return NULL;
911 
912 	if (unlikely(!dst_sg || !src_sg))
913 		return NULL;
914 
915 	chan = to_dma_chan(dchan);
916 
917 	/* Get prepared for the loop */
918 	dst_avail = sg_dma_len(dst_sg);
919 	src_avail = sg_dma_len(src_sg);
920 	dst_nents--;
921 	src_nents--;
922 
923 	/* Run until we are out of scatterlist entries */
924 	while (true) {
925 		/* Create the largest transaction possible */
926 		len = min_t(size_t, src_avail, dst_avail);
927 		len = min_t(size_t, len, XGENE_DMA_MAX_64B_DESC_BYTE_CNT);
928 		if (len == 0)
929 			goto fetch;
930 
931 		dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) - dst_avail;
932 		src = sg_dma_address(src_sg) + sg_dma_len(src_sg) - src_avail;
933 
934 		/* Allocate the link descriptor from DMA pool */
935 		new = xgene_dma_alloc_descriptor(chan);
936 		if (!new)
937 			goto fail;
938 
939 		/* Prepare DMA descriptor */
940 		xgene_dma_prep_cpy_desc(chan, new, dst, src, len);
941 
942 		if (!first)
943 			first = new;
944 
945 		new->tx.cookie = 0;
946 		async_tx_ack(&new->tx);
947 
948 		/* update metadata */
949 		dst_avail -= len;
950 		src_avail -= len;
951 
952 		/* Insert the link descriptor to the LD ring */
953 		list_add_tail(&new->node, &first->tx_list);
954 
955 fetch:
956 		/* fetch the next dst scatterlist entry */
957 		if (dst_avail == 0) {
958 			/* no more entries: we're done */
959 			if (dst_nents == 0)
960 				break;
961 
962 			/* fetch the next entry: if there are no more: done */
963 			dst_sg = sg_next(dst_sg);
964 			if (!dst_sg)
965 				break;
966 
967 			dst_nents--;
968 			dst_avail = sg_dma_len(dst_sg);
969 		}
970 
971 		/* fetch the next src scatterlist entry */
972 		if (src_avail == 0) {
973 			/* no more entries: we're done */
974 			if (src_nents == 0)
975 				break;
976 
977 			/* fetch the next entry: if there are no more: done */
978 			src_sg = sg_next(src_sg);
979 			if (!src_sg)
980 				break;
981 
982 			src_nents--;
983 			src_avail = sg_dma_len(src_sg);
984 		}
985 	}
986 
987 	if (!new)
988 		return NULL;
989 
990 	new->tx.flags = flags; /* client is in control of this ack */
991 	new->tx.cookie = -EBUSY;
992 	list_splice(&first->tx_list, &new->tx_list);
993 
994 	return &new->tx;
995 fail:
996 	if (!first)
997 		return NULL;
998 
999 	xgene_dma_free_desc_list(chan, &first->tx_list);
1000 	return NULL;
1001 }
1002 
1003 static struct dma_async_tx_descriptor *xgene_dma_prep_xor(
1004 	struct dma_chan *dchan, dma_addr_t dst,	dma_addr_t *src,
1005 	u32 src_cnt, size_t len, unsigned long flags)
1006 {
1007 	struct xgene_dma_desc_sw *first = NULL, *new;
1008 	struct xgene_dma_chan *chan;
1009 	static u8 multi[XGENE_DMA_MAX_XOR_SRC] = {
1010 				0x01, 0x01, 0x01, 0x01, 0x01};
1011 
1012 	if (unlikely(!dchan || !len))
1013 		return NULL;
1014 
1015 	chan = to_dma_chan(dchan);
1016 
1017 	do {
1018 		/* Allocate the link descriptor from DMA pool */
1019 		new = xgene_dma_alloc_descriptor(chan);
1020 		if (!new)
1021 			goto fail;
1022 
1023 		/* Prepare xor DMA descriptor */
1024 		xgene_dma_prep_xor_desc(chan, new, &dst, src,
1025 					src_cnt, &len, multi);
1026 
1027 		if (!first)
1028 			first = new;
1029 
1030 		new->tx.cookie = 0;
1031 		async_tx_ack(&new->tx);
1032 
1033 		/* Insert the link descriptor to the LD ring */
1034 		list_add_tail(&new->node, &first->tx_list);
1035 	} while (len);
1036 
1037 	new->tx.flags = flags; /* client is in control of this ack */
1038 	new->tx.cookie = -EBUSY;
1039 	list_splice(&first->tx_list, &new->tx_list);
1040 
1041 	return &new->tx;
1042 
1043 fail:
1044 	if (!first)
1045 		return NULL;
1046 
1047 	xgene_dma_free_desc_list(chan, &first->tx_list);
1048 	return NULL;
1049 }
1050 
1051 static struct dma_async_tx_descriptor *xgene_dma_prep_pq(
1052 	struct dma_chan *dchan, dma_addr_t *dst, dma_addr_t *src,
1053 	u32 src_cnt, const u8 *scf, size_t len, unsigned long flags)
1054 {
1055 	struct xgene_dma_desc_sw *first = NULL, *new;
1056 	struct xgene_dma_chan *chan;
1057 	size_t _len = len;
1058 	dma_addr_t _src[XGENE_DMA_MAX_XOR_SRC];
1059 	static u8 multi[XGENE_DMA_MAX_XOR_SRC] = {0x01, 0x01, 0x01, 0x01, 0x01};
1060 
1061 	if (unlikely(!dchan || !len))
1062 		return NULL;
1063 
1064 	chan = to_dma_chan(dchan);
1065 
1066 	/*
1067 	 * Save source addresses on local variable, may be we have to
1068 	 * prepare two descriptor to generate P and Q if both enabled
1069 	 * in the flags by client
1070 	 */
1071 	memcpy(_src, src, sizeof(*src) * src_cnt);
1072 
1073 	if (flags & DMA_PREP_PQ_DISABLE_P)
1074 		len = 0;
1075 
1076 	if (flags & DMA_PREP_PQ_DISABLE_Q)
1077 		_len = 0;
1078 
1079 	do {
1080 		/* Allocate the link descriptor from DMA pool */
1081 		new = xgene_dma_alloc_descriptor(chan);
1082 		if (!new)
1083 			goto fail;
1084 
1085 		if (!first)
1086 			first = new;
1087 
1088 		new->tx.cookie = 0;
1089 		async_tx_ack(&new->tx);
1090 
1091 		/* Insert the link descriptor to the LD ring */
1092 		list_add_tail(&new->node, &first->tx_list);
1093 
1094 		/*
1095 		 * Prepare DMA descriptor to generate P,
1096 		 * if DMA_PREP_PQ_DISABLE_P flag is not set
1097 		 */
1098 		if (len) {
1099 			xgene_dma_prep_xor_desc(chan, new, &dst[0], src,
1100 						src_cnt, &len, multi);
1101 			continue;
1102 		}
1103 
1104 		/*
1105 		 * Prepare DMA descriptor to generate Q,
1106 		 * if DMA_PREP_PQ_DISABLE_Q flag is not set
1107 		 */
1108 		if (_len) {
1109 			xgene_dma_prep_xor_desc(chan, new, &dst[1], _src,
1110 						src_cnt, &_len, scf);
1111 		}
1112 	} while (len || _len);
1113 
1114 	new->tx.flags = flags; /* client is in control of this ack */
1115 	new->tx.cookie = -EBUSY;
1116 	list_splice(&first->tx_list, &new->tx_list);
1117 
1118 	return &new->tx;
1119 
1120 fail:
1121 	if (!first)
1122 		return NULL;
1123 
1124 	xgene_dma_free_desc_list(chan, &first->tx_list);
1125 	return NULL;
1126 }
1127 
1128 static void xgene_dma_issue_pending(struct dma_chan *dchan)
1129 {
1130 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
1131 
1132 	spin_lock_bh(&chan->lock);
1133 	xgene_chan_xfer_ld_pending(chan);
1134 	spin_unlock_bh(&chan->lock);
1135 }
1136 
1137 static enum dma_status xgene_dma_tx_status(struct dma_chan *dchan,
1138 					   dma_cookie_t cookie,
1139 					   struct dma_tx_state *txstate)
1140 {
1141 	return dma_cookie_status(dchan, cookie, txstate);
1142 }
1143 
1144 static void xgene_dma_tasklet_cb(unsigned long data)
1145 {
1146 	struct xgene_dma_chan *chan = (struct xgene_dma_chan *)data;
1147 
1148 	/* Run all cleanup for descriptors which have been completed */
1149 	xgene_dma_cleanup_descriptors(chan);
1150 
1151 	/* Re-enable DMA channel IRQ */
1152 	enable_irq(chan->rx_irq);
1153 }
1154 
1155 static irqreturn_t xgene_dma_chan_ring_isr(int irq, void *id)
1156 {
1157 	struct xgene_dma_chan *chan = (struct xgene_dma_chan *)id;
1158 
1159 	BUG_ON(!chan);
1160 
1161 	/*
1162 	 * Disable DMA channel IRQ until we process completed
1163 	 * descriptors
1164 	 */
1165 	disable_irq_nosync(chan->rx_irq);
1166 
1167 	/*
1168 	 * Schedule the tasklet to handle all cleanup of the current
1169 	 * transaction. It will start a new transaction if there is
1170 	 * one pending.
1171 	 */
1172 	tasklet_schedule(&chan->tasklet);
1173 
1174 	return IRQ_HANDLED;
1175 }
1176 
1177 static irqreturn_t xgene_dma_err_isr(int irq, void *id)
1178 {
1179 	struct xgene_dma *pdma = (struct xgene_dma *)id;
1180 	unsigned long int_mask;
1181 	u32 val, i;
1182 
1183 	val = ioread32(pdma->csr_dma + XGENE_DMA_INT);
1184 
1185 	/* Clear DMA interrupts */
1186 	iowrite32(val, pdma->csr_dma + XGENE_DMA_INT);
1187 
1188 	/* Print DMA error info */
1189 	int_mask = val >> XGENE_DMA_INT_MASK_SHIFT;
1190 	for_each_set_bit(i, &int_mask, ARRAY_SIZE(xgene_dma_err))
1191 		dev_err(pdma->dev,
1192 			"Interrupt status 0x%08X %s\n", val, xgene_dma_err[i]);
1193 
1194 	return IRQ_HANDLED;
1195 }
1196 
1197 static void xgene_dma_wr_ring_state(struct xgene_dma_ring *ring)
1198 {
1199 	int i;
1200 
1201 	iowrite32(ring->num, ring->pdma->csr_ring + XGENE_DMA_RING_STATE);
1202 
1203 	for (i = 0; i < XGENE_DMA_RING_NUM_CONFIG; i++)
1204 		iowrite32(ring->state[i], ring->pdma->csr_ring +
1205 			  XGENE_DMA_RING_STATE_WR_BASE + (i * 4));
1206 }
1207 
1208 static void xgene_dma_clr_ring_state(struct xgene_dma_ring *ring)
1209 {
1210 	memset(ring->state, 0, sizeof(u32) * XGENE_DMA_RING_NUM_CONFIG);
1211 	xgene_dma_wr_ring_state(ring);
1212 }
1213 
1214 static void xgene_dma_setup_ring(struct xgene_dma_ring *ring)
1215 {
1216 	void *ring_cfg = ring->state;
1217 	u64 addr = ring->desc_paddr;
1218 	u32 i, val;
1219 
1220 	ring->slots = ring->size / XGENE_DMA_RING_WQ_DESC_SIZE;
1221 
1222 	/* Clear DMA ring state */
1223 	xgene_dma_clr_ring_state(ring);
1224 
1225 	/* Set DMA ring type */
1226 	XGENE_DMA_RING_TYPE_SET(ring_cfg, XGENE_DMA_RING_TYPE_REGULAR);
1227 
1228 	if (ring->owner == XGENE_DMA_RING_OWNER_DMA) {
1229 		/* Set recombination buffer and timeout */
1230 		XGENE_DMA_RING_RECOMBBUF_SET(ring_cfg);
1231 		XGENE_DMA_RING_RECOMTIMEOUTL_SET(ring_cfg);
1232 		XGENE_DMA_RING_RECOMTIMEOUTH_SET(ring_cfg);
1233 	}
1234 
1235 	/* Initialize DMA ring state */
1236 	XGENE_DMA_RING_SELTHRSH_SET(ring_cfg);
1237 	XGENE_DMA_RING_ACCEPTLERR_SET(ring_cfg);
1238 	XGENE_DMA_RING_COHERENT_SET(ring_cfg);
1239 	XGENE_DMA_RING_ADDRL_SET(ring_cfg, addr);
1240 	XGENE_DMA_RING_ADDRH_SET(ring_cfg, addr);
1241 	XGENE_DMA_RING_SIZE_SET(ring_cfg, ring->cfgsize);
1242 
1243 	/* Write DMA ring configurations */
1244 	xgene_dma_wr_ring_state(ring);
1245 
1246 	/* Set DMA ring id */
1247 	iowrite32(XGENE_DMA_RING_ID_SETUP(ring->id),
1248 		  ring->pdma->csr_ring + XGENE_DMA_RING_ID);
1249 
1250 	/* Set DMA ring buffer */
1251 	iowrite32(XGENE_DMA_RING_ID_BUF_SETUP(ring->num),
1252 		  ring->pdma->csr_ring + XGENE_DMA_RING_ID_BUF);
1253 
1254 	if (ring->owner != XGENE_DMA_RING_OWNER_CPU)
1255 		return;
1256 
1257 	/* Set empty signature to DMA Rx ring descriptors */
1258 	for (i = 0; i < ring->slots; i++) {
1259 		struct xgene_dma_desc_hw *desc;
1260 
1261 		desc = &ring->desc_hw[i];
1262 		desc->m0 = cpu_to_le64(XGENE_DMA_DESC_EMPTY_SIGNATURE);
1263 	}
1264 
1265 	/* Enable DMA Rx ring interrupt */
1266 	val = ioread32(ring->pdma->csr_ring + XGENE_DMA_RING_NE_INT_MODE);
1267 	XGENE_DMA_RING_NE_INT_MODE_SET(val, ring->buf_num);
1268 	iowrite32(val, ring->pdma->csr_ring + XGENE_DMA_RING_NE_INT_MODE);
1269 }
1270 
1271 static void xgene_dma_clear_ring(struct xgene_dma_ring *ring)
1272 {
1273 	u32 ring_id, val;
1274 
1275 	if (ring->owner == XGENE_DMA_RING_OWNER_CPU) {
1276 		/* Disable DMA Rx ring interrupt */
1277 		val = ioread32(ring->pdma->csr_ring +
1278 			       XGENE_DMA_RING_NE_INT_MODE);
1279 		XGENE_DMA_RING_NE_INT_MODE_RESET(val, ring->buf_num);
1280 		iowrite32(val, ring->pdma->csr_ring +
1281 			  XGENE_DMA_RING_NE_INT_MODE);
1282 	}
1283 
1284 	/* Clear DMA ring state */
1285 	ring_id = XGENE_DMA_RING_ID_SETUP(ring->id);
1286 	iowrite32(ring_id, ring->pdma->csr_ring + XGENE_DMA_RING_ID);
1287 
1288 	iowrite32(0, ring->pdma->csr_ring + XGENE_DMA_RING_ID_BUF);
1289 	xgene_dma_clr_ring_state(ring);
1290 }
1291 
1292 static void xgene_dma_set_ring_cmd(struct xgene_dma_ring *ring)
1293 {
1294 	ring->cmd_base = ring->pdma->csr_ring_cmd +
1295 				XGENE_DMA_RING_CMD_BASE_OFFSET((ring->num -
1296 							  XGENE_DMA_RING_NUM));
1297 
1298 	ring->cmd = ring->cmd_base + XGENE_DMA_RING_CMD_OFFSET;
1299 }
1300 
1301 static int xgene_dma_get_ring_size(struct xgene_dma_chan *chan,
1302 				   enum xgene_dma_ring_cfgsize cfgsize)
1303 {
1304 	int size;
1305 
1306 	switch (cfgsize) {
1307 	case XGENE_DMA_RING_CFG_SIZE_512B:
1308 		size = 0x200;
1309 		break;
1310 	case XGENE_DMA_RING_CFG_SIZE_2KB:
1311 		size = 0x800;
1312 		break;
1313 	case XGENE_DMA_RING_CFG_SIZE_16KB:
1314 		size = 0x4000;
1315 		break;
1316 	case XGENE_DMA_RING_CFG_SIZE_64KB:
1317 		size = 0x10000;
1318 		break;
1319 	case XGENE_DMA_RING_CFG_SIZE_512KB:
1320 		size = 0x80000;
1321 		break;
1322 	default:
1323 		chan_err(chan, "Unsupported cfg ring size %d\n", cfgsize);
1324 		return -EINVAL;
1325 	}
1326 
1327 	return size;
1328 }
1329 
1330 static void xgene_dma_delete_ring_one(struct xgene_dma_ring *ring)
1331 {
1332 	/* Clear DMA ring configurations */
1333 	xgene_dma_clear_ring(ring);
1334 
1335 	/* De-allocate DMA ring descriptor */
1336 	if (ring->desc_vaddr) {
1337 		dma_free_coherent(ring->pdma->dev, ring->size,
1338 				  ring->desc_vaddr, ring->desc_paddr);
1339 		ring->desc_vaddr = NULL;
1340 	}
1341 }
1342 
1343 static void xgene_dma_delete_chan_rings(struct xgene_dma_chan *chan)
1344 {
1345 	xgene_dma_delete_ring_one(&chan->rx_ring);
1346 	xgene_dma_delete_ring_one(&chan->tx_ring);
1347 }
1348 
1349 static int xgene_dma_create_ring_one(struct xgene_dma_chan *chan,
1350 				     struct xgene_dma_ring *ring,
1351 				     enum xgene_dma_ring_cfgsize cfgsize)
1352 {
1353 	int ret;
1354 
1355 	/* Setup DMA ring descriptor variables */
1356 	ring->pdma = chan->pdma;
1357 	ring->cfgsize = cfgsize;
1358 	ring->num = chan->pdma->ring_num++;
1359 	ring->id = XGENE_DMA_RING_ID_GET(ring->owner, ring->buf_num);
1360 
1361 	ret = xgene_dma_get_ring_size(chan, cfgsize);
1362 	if (ret <= 0)
1363 		return ret;
1364 	ring->size = ret;
1365 
1366 	/* Allocate memory for DMA ring descriptor */
1367 	ring->desc_vaddr = dma_zalloc_coherent(chan->dev, ring->size,
1368 					       &ring->desc_paddr, GFP_KERNEL);
1369 	if (!ring->desc_vaddr) {
1370 		chan_err(chan, "Failed to allocate ring desc\n");
1371 		return -ENOMEM;
1372 	}
1373 
1374 	/* Configure and enable DMA ring */
1375 	xgene_dma_set_ring_cmd(ring);
1376 	xgene_dma_setup_ring(ring);
1377 
1378 	return 0;
1379 }
1380 
1381 static int xgene_dma_create_chan_rings(struct xgene_dma_chan *chan)
1382 {
1383 	struct xgene_dma_ring *rx_ring = &chan->rx_ring;
1384 	struct xgene_dma_ring *tx_ring = &chan->tx_ring;
1385 	int ret;
1386 
1387 	/* Create DMA Rx ring descriptor */
1388 	rx_ring->owner = XGENE_DMA_RING_OWNER_CPU;
1389 	rx_ring->buf_num = XGENE_DMA_CPU_BUFNUM + chan->id;
1390 
1391 	ret = xgene_dma_create_ring_one(chan, rx_ring,
1392 					XGENE_DMA_RING_CFG_SIZE_64KB);
1393 	if (ret)
1394 		return ret;
1395 
1396 	chan_dbg(chan, "Rx ring id 0x%X num %d desc 0x%p\n",
1397 		 rx_ring->id, rx_ring->num, rx_ring->desc_vaddr);
1398 
1399 	/* Create DMA Tx ring descriptor */
1400 	tx_ring->owner = XGENE_DMA_RING_OWNER_DMA;
1401 	tx_ring->buf_num = XGENE_DMA_BUFNUM + chan->id;
1402 
1403 	ret = xgene_dma_create_ring_one(chan, tx_ring,
1404 					XGENE_DMA_RING_CFG_SIZE_64KB);
1405 	if (ret) {
1406 		xgene_dma_delete_ring_one(rx_ring);
1407 		return ret;
1408 	}
1409 
1410 	tx_ring->dst_ring_num = XGENE_DMA_RING_DST_ID(rx_ring->num);
1411 
1412 	chan_dbg(chan,
1413 		 "Tx ring id 0x%X num %d desc 0x%p\n",
1414 		 tx_ring->id, tx_ring->num, tx_ring->desc_vaddr);
1415 
1416 	/* Set the max outstanding request possible to this channel */
1417 	chan->max_outstanding = tx_ring->slots;
1418 
1419 	return ret;
1420 }
1421 
1422 static int xgene_dma_init_rings(struct xgene_dma *pdma)
1423 {
1424 	int ret, i, j;
1425 
1426 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1427 		ret = xgene_dma_create_chan_rings(&pdma->chan[i]);
1428 		if (ret) {
1429 			for (j = 0; j < i; j++)
1430 				xgene_dma_delete_chan_rings(&pdma->chan[j]);
1431 			return ret;
1432 		}
1433 	}
1434 
1435 	return ret;
1436 }
1437 
1438 static void xgene_dma_enable(struct xgene_dma *pdma)
1439 {
1440 	u32 val;
1441 
1442 	/* Configure and enable DMA engine */
1443 	val = ioread32(pdma->csr_dma + XGENE_DMA_GCR);
1444 	XGENE_DMA_CH_SETUP(val);
1445 	XGENE_DMA_ENABLE(val);
1446 	iowrite32(val, pdma->csr_dma + XGENE_DMA_GCR);
1447 }
1448 
1449 static void xgene_dma_disable(struct xgene_dma *pdma)
1450 {
1451 	u32 val;
1452 
1453 	val = ioread32(pdma->csr_dma + XGENE_DMA_GCR);
1454 	XGENE_DMA_DISABLE(val);
1455 	iowrite32(val, pdma->csr_dma + XGENE_DMA_GCR);
1456 }
1457 
1458 static void xgene_dma_mask_interrupts(struct xgene_dma *pdma)
1459 {
1460 	/*
1461 	 * Mask DMA ring overflow, underflow and
1462 	 * AXI write/read error interrupts
1463 	 */
1464 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1465 		  pdma->csr_dma + XGENE_DMA_RING_INT0_MASK);
1466 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1467 		  pdma->csr_dma + XGENE_DMA_RING_INT1_MASK);
1468 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1469 		  pdma->csr_dma + XGENE_DMA_RING_INT2_MASK);
1470 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1471 		  pdma->csr_dma + XGENE_DMA_RING_INT3_MASK);
1472 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1473 		  pdma->csr_dma + XGENE_DMA_RING_INT4_MASK);
1474 
1475 	/* Mask DMA error interrupts */
1476 	iowrite32(XGENE_DMA_INT_ALL_MASK, pdma->csr_dma + XGENE_DMA_INT_MASK);
1477 }
1478 
1479 static void xgene_dma_unmask_interrupts(struct xgene_dma *pdma)
1480 {
1481 	/*
1482 	 * Unmask DMA ring overflow, underflow and
1483 	 * AXI write/read error interrupts
1484 	 */
1485 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1486 		  pdma->csr_dma + XGENE_DMA_RING_INT0_MASK);
1487 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1488 		  pdma->csr_dma + XGENE_DMA_RING_INT1_MASK);
1489 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1490 		  pdma->csr_dma + XGENE_DMA_RING_INT2_MASK);
1491 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1492 		  pdma->csr_dma + XGENE_DMA_RING_INT3_MASK);
1493 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1494 		  pdma->csr_dma + XGENE_DMA_RING_INT4_MASK);
1495 
1496 	/* Unmask DMA error interrupts */
1497 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1498 		  pdma->csr_dma + XGENE_DMA_INT_MASK);
1499 }
1500 
1501 static void xgene_dma_init_hw(struct xgene_dma *pdma)
1502 {
1503 	u32 val;
1504 
1505 	/* Associate DMA ring to corresponding ring HW */
1506 	iowrite32(XGENE_DMA_ASSOC_RING_MNGR1,
1507 		  pdma->csr_dma + XGENE_DMA_CFG_RING_WQ_ASSOC);
1508 
1509 	/* Configure RAID6 polynomial control setting */
1510 	if (is_pq_enabled(pdma))
1511 		iowrite32(XGENE_DMA_RAID6_MULTI_CTRL(0x1D),
1512 			  pdma->csr_dma + XGENE_DMA_RAID6_CONT);
1513 	else
1514 		dev_info(pdma->dev, "PQ is disabled in HW\n");
1515 
1516 	xgene_dma_enable(pdma);
1517 	xgene_dma_unmask_interrupts(pdma);
1518 
1519 	/* Get DMA id and version info */
1520 	val = ioread32(pdma->csr_dma + XGENE_DMA_IPBRR);
1521 
1522 	/* DMA device info */
1523 	dev_info(pdma->dev,
1524 		 "X-Gene DMA v%d.%02d.%02d driver registered %d channels",
1525 		 XGENE_DMA_REV_NO_RD(val), XGENE_DMA_BUS_ID_RD(val),
1526 		 XGENE_DMA_DEV_ID_RD(val), XGENE_DMA_MAX_CHANNEL);
1527 }
1528 
1529 static int xgene_dma_init_ring_mngr(struct xgene_dma *pdma)
1530 {
1531 	if (ioread32(pdma->csr_ring + XGENE_DMA_RING_CLKEN) &&
1532 	    (!ioread32(pdma->csr_ring + XGENE_DMA_RING_SRST)))
1533 		return 0;
1534 
1535 	iowrite32(0x3, pdma->csr_ring + XGENE_DMA_RING_CLKEN);
1536 	iowrite32(0x0, pdma->csr_ring + XGENE_DMA_RING_SRST);
1537 
1538 	/* Bring up memory */
1539 	iowrite32(0x0, pdma->csr_ring + XGENE_DMA_RING_MEM_RAM_SHUTDOWN);
1540 
1541 	/* Force a barrier */
1542 	ioread32(pdma->csr_ring + XGENE_DMA_RING_MEM_RAM_SHUTDOWN);
1543 
1544 	/* reset may take up to 1ms */
1545 	usleep_range(1000, 1100);
1546 
1547 	if (ioread32(pdma->csr_ring + XGENE_DMA_RING_BLK_MEM_RDY)
1548 		!= XGENE_DMA_RING_BLK_MEM_RDY_VAL) {
1549 		dev_err(pdma->dev,
1550 			"Failed to release ring mngr memory from shutdown\n");
1551 		return -ENODEV;
1552 	}
1553 
1554 	/* program threshold set 1 and all hysteresis */
1555 	iowrite32(XGENE_DMA_RING_THRESLD0_SET1_VAL,
1556 		  pdma->csr_ring + XGENE_DMA_RING_THRESLD0_SET1);
1557 	iowrite32(XGENE_DMA_RING_THRESLD1_SET1_VAL,
1558 		  pdma->csr_ring + XGENE_DMA_RING_THRESLD1_SET1);
1559 	iowrite32(XGENE_DMA_RING_HYSTERESIS_VAL,
1560 		  pdma->csr_ring + XGENE_DMA_RING_HYSTERESIS);
1561 
1562 	/* Enable QPcore and assign error queue */
1563 	iowrite32(XGENE_DMA_RING_ENABLE,
1564 		  pdma->csr_ring + XGENE_DMA_RING_CONFIG);
1565 
1566 	return 0;
1567 }
1568 
1569 static int xgene_dma_init_mem(struct xgene_dma *pdma)
1570 {
1571 	int ret;
1572 
1573 	ret = xgene_dma_init_ring_mngr(pdma);
1574 	if (ret)
1575 		return ret;
1576 
1577 	/* Bring up memory */
1578 	iowrite32(0x0, pdma->csr_dma + XGENE_DMA_MEM_RAM_SHUTDOWN);
1579 
1580 	/* Force a barrier */
1581 	ioread32(pdma->csr_dma + XGENE_DMA_MEM_RAM_SHUTDOWN);
1582 
1583 	/* reset may take up to 1ms */
1584 	usleep_range(1000, 1100);
1585 
1586 	if (ioread32(pdma->csr_dma + XGENE_DMA_BLK_MEM_RDY)
1587 		!= XGENE_DMA_BLK_MEM_RDY_VAL) {
1588 		dev_err(pdma->dev,
1589 			"Failed to release DMA memory from shutdown\n");
1590 		return -ENODEV;
1591 	}
1592 
1593 	return 0;
1594 }
1595 
1596 static int xgene_dma_request_irqs(struct xgene_dma *pdma)
1597 {
1598 	struct xgene_dma_chan *chan;
1599 	int ret, i, j;
1600 
1601 	/* Register DMA error irq */
1602 	ret = devm_request_irq(pdma->dev, pdma->err_irq, xgene_dma_err_isr,
1603 			       0, "dma_error", pdma);
1604 	if (ret) {
1605 		dev_err(pdma->dev,
1606 			"Failed to register error IRQ %d\n", pdma->err_irq);
1607 		return ret;
1608 	}
1609 
1610 	/* Register DMA channel rx irq */
1611 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1612 		chan = &pdma->chan[i];
1613 		ret = devm_request_irq(chan->dev, chan->rx_irq,
1614 				       xgene_dma_chan_ring_isr,
1615 				       0, chan->name, chan);
1616 		if (ret) {
1617 			chan_err(chan, "Failed to register Rx IRQ %d\n",
1618 				 chan->rx_irq);
1619 			devm_free_irq(pdma->dev, pdma->err_irq, pdma);
1620 
1621 			for (j = 0; j < i; j++) {
1622 				chan = &pdma->chan[i];
1623 				devm_free_irq(chan->dev, chan->rx_irq, chan);
1624 			}
1625 
1626 			return ret;
1627 		}
1628 	}
1629 
1630 	return 0;
1631 }
1632 
1633 static void xgene_dma_free_irqs(struct xgene_dma *pdma)
1634 {
1635 	struct xgene_dma_chan *chan;
1636 	int i;
1637 
1638 	/* Free DMA device error irq */
1639 	devm_free_irq(pdma->dev, pdma->err_irq, pdma);
1640 
1641 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1642 		chan = &pdma->chan[i];
1643 		devm_free_irq(chan->dev, chan->rx_irq, chan);
1644 	}
1645 }
1646 
1647 static void xgene_dma_set_caps(struct xgene_dma_chan *chan,
1648 			       struct dma_device *dma_dev)
1649 {
1650 	/* Initialize DMA device capability mask */
1651 	dma_cap_zero(dma_dev->cap_mask);
1652 
1653 	/* Set DMA device capability */
1654 	dma_cap_set(DMA_SG, dma_dev->cap_mask);
1655 
1656 	/* Basically here, the X-Gene SoC DMA engine channel 0 supports XOR
1657 	 * and channel 1 supports XOR, PQ both. First thing here is we have
1658 	 * mechanism in hw to enable/disable PQ/XOR supports on channel 1,
1659 	 * we can make sure this by reading SoC Efuse register.
1660 	 * Second thing, we have hw errata that if we run channel 0 and
1661 	 * channel 1 simultaneously with executing XOR and PQ request,
1662 	 * suddenly DMA engine hangs, So here we enable XOR on channel 0 only
1663 	 * if XOR and PQ supports on channel 1 is disabled.
1664 	 */
1665 	if ((chan->id == XGENE_DMA_PQ_CHANNEL) &&
1666 	    is_pq_enabled(chan->pdma)) {
1667 		dma_cap_set(DMA_PQ, dma_dev->cap_mask);
1668 		dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1669 	} else if ((chan->id == XGENE_DMA_XOR_CHANNEL) &&
1670 		   !is_pq_enabled(chan->pdma)) {
1671 		dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1672 	}
1673 
1674 	/* Set base and prep routines */
1675 	dma_dev->dev = chan->dev;
1676 	dma_dev->device_alloc_chan_resources = xgene_dma_alloc_chan_resources;
1677 	dma_dev->device_free_chan_resources = xgene_dma_free_chan_resources;
1678 	dma_dev->device_issue_pending = xgene_dma_issue_pending;
1679 	dma_dev->device_tx_status = xgene_dma_tx_status;
1680 	dma_dev->device_prep_dma_sg = xgene_dma_prep_sg;
1681 
1682 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1683 		dma_dev->device_prep_dma_xor = xgene_dma_prep_xor;
1684 		dma_dev->max_xor = XGENE_DMA_MAX_XOR_SRC;
1685 		dma_dev->xor_align = DMAENGINE_ALIGN_64_BYTES;
1686 	}
1687 
1688 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
1689 		dma_dev->device_prep_dma_pq = xgene_dma_prep_pq;
1690 		dma_dev->max_pq = XGENE_DMA_MAX_XOR_SRC;
1691 		dma_dev->pq_align = DMAENGINE_ALIGN_64_BYTES;
1692 	}
1693 }
1694 
1695 static int xgene_dma_async_register(struct xgene_dma *pdma, int id)
1696 {
1697 	struct xgene_dma_chan *chan = &pdma->chan[id];
1698 	struct dma_device *dma_dev = &pdma->dma_dev[id];
1699 	int ret;
1700 
1701 	chan->dma_chan.device = dma_dev;
1702 
1703 	spin_lock_init(&chan->lock);
1704 	INIT_LIST_HEAD(&chan->ld_pending);
1705 	INIT_LIST_HEAD(&chan->ld_running);
1706 	INIT_LIST_HEAD(&chan->ld_completed);
1707 	tasklet_init(&chan->tasklet, xgene_dma_tasklet_cb,
1708 		     (unsigned long)chan);
1709 
1710 	chan->pending = 0;
1711 	chan->desc_pool = NULL;
1712 	dma_cookie_init(&chan->dma_chan);
1713 
1714 	/* Setup dma device capabilities and prep routines */
1715 	xgene_dma_set_caps(chan, dma_dev);
1716 
1717 	/* Initialize DMA device list head */
1718 	INIT_LIST_HEAD(&dma_dev->channels);
1719 	list_add_tail(&chan->dma_chan.device_node, &dma_dev->channels);
1720 
1721 	/* Register with Linux async DMA framework*/
1722 	ret = dma_async_device_register(dma_dev);
1723 	if (ret) {
1724 		chan_err(chan, "Failed to register async device %d", ret);
1725 		tasklet_kill(&chan->tasklet);
1726 
1727 		return ret;
1728 	}
1729 
1730 	/* DMA capability info */
1731 	dev_info(pdma->dev,
1732 		 "%s: CAPABILITY ( %s%s%s)\n", dma_chan_name(&chan->dma_chan),
1733 		 dma_has_cap(DMA_SG, dma_dev->cap_mask) ? "SGCPY " : "",
1734 		 dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "XOR " : "",
1735 		 dma_has_cap(DMA_PQ, dma_dev->cap_mask) ? "PQ " : "");
1736 
1737 	return 0;
1738 }
1739 
1740 static int xgene_dma_init_async(struct xgene_dma *pdma)
1741 {
1742 	int ret, i, j;
1743 
1744 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL ; i++) {
1745 		ret = xgene_dma_async_register(pdma, i);
1746 		if (ret) {
1747 			for (j = 0; j < i; j++) {
1748 				dma_async_device_unregister(&pdma->dma_dev[j]);
1749 				tasklet_kill(&pdma->chan[j].tasklet);
1750 			}
1751 
1752 			return ret;
1753 		}
1754 	}
1755 
1756 	return ret;
1757 }
1758 
1759 static void xgene_dma_async_unregister(struct xgene_dma *pdma)
1760 {
1761 	int i;
1762 
1763 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++)
1764 		dma_async_device_unregister(&pdma->dma_dev[i]);
1765 }
1766 
1767 static void xgene_dma_init_channels(struct xgene_dma *pdma)
1768 {
1769 	struct xgene_dma_chan *chan;
1770 	int i;
1771 
1772 	pdma->ring_num = XGENE_DMA_RING_NUM;
1773 
1774 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1775 		chan = &pdma->chan[i];
1776 		chan->dev = pdma->dev;
1777 		chan->pdma = pdma;
1778 		chan->id = i;
1779 		snprintf(chan->name, sizeof(chan->name), "dmachan%d", chan->id);
1780 	}
1781 }
1782 
1783 static int xgene_dma_get_resources(struct platform_device *pdev,
1784 				   struct xgene_dma *pdma)
1785 {
1786 	struct resource *res;
1787 	int irq, i;
1788 
1789 	/* Get DMA csr region */
1790 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1791 	if (!res) {
1792 		dev_err(&pdev->dev, "Failed to get csr region\n");
1793 		return -ENXIO;
1794 	}
1795 
1796 	pdma->csr_dma = devm_ioremap(&pdev->dev, res->start,
1797 				     resource_size(res));
1798 	if (!pdma->csr_dma) {
1799 		dev_err(&pdev->dev, "Failed to ioremap csr region");
1800 		return -ENOMEM;
1801 	}
1802 
1803 	/* Get DMA ring csr region */
1804 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1805 	if (!res) {
1806 		dev_err(&pdev->dev, "Failed to get ring csr region\n");
1807 		return -ENXIO;
1808 	}
1809 
1810 	pdma->csr_ring =  devm_ioremap(&pdev->dev, res->start,
1811 				       resource_size(res));
1812 	if (!pdma->csr_ring) {
1813 		dev_err(&pdev->dev, "Failed to ioremap ring csr region");
1814 		return -ENOMEM;
1815 	}
1816 
1817 	/* Get DMA ring cmd csr region */
1818 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
1819 	if (!res) {
1820 		dev_err(&pdev->dev, "Failed to get ring cmd csr region\n");
1821 		return -ENXIO;
1822 	}
1823 
1824 	pdma->csr_ring_cmd = devm_ioremap(&pdev->dev, res->start,
1825 					  resource_size(res));
1826 	if (!pdma->csr_ring_cmd) {
1827 		dev_err(&pdev->dev, "Failed to ioremap ring cmd csr region");
1828 		return -ENOMEM;
1829 	}
1830 
1831 	pdma->csr_ring_cmd += XGENE_DMA_RING_CMD_SM_OFFSET;
1832 
1833 	/* Get efuse csr region */
1834 	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
1835 	if (!res) {
1836 		dev_err(&pdev->dev, "Failed to get efuse csr region\n");
1837 		return -ENXIO;
1838 	}
1839 
1840 	pdma->csr_efuse = devm_ioremap(&pdev->dev, res->start,
1841 				       resource_size(res));
1842 	if (!pdma->csr_efuse) {
1843 		dev_err(&pdev->dev, "Failed to ioremap efuse csr region");
1844 		return -ENOMEM;
1845 	}
1846 
1847 	/* Get DMA error interrupt */
1848 	irq = platform_get_irq(pdev, 0);
1849 	if (irq <= 0) {
1850 		dev_err(&pdev->dev, "Failed to get Error IRQ\n");
1851 		return -ENXIO;
1852 	}
1853 
1854 	pdma->err_irq = irq;
1855 
1856 	/* Get DMA Rx ring descriptor interrupts for all DMA channels */
1857 	for (i = 1; i <= XGENE_DMA_MAX_CHANNEL; i++) {
1858 		irq = platform_get_irq(pdev, i);
1859 		if (irq <= 0) {
1860 			dev_err(&pdev->dev, "Failed to get Rx IRQ\n");
1861 			return -ENXIO;
1862 		}
1863 
1864 		pdma->chan[i - 1].rx_irq = irq;
1865 	}
1866 
1867 	return 0;
1868 }
1869 
1870 static int xgene_dma_probe(struct platform_device *pdev)
1871 {
1872 	struct xgene_dma *pdma;
1873 	int ret, i;
1874 
1875 	pdma = devm_kzalloc(&pdev->dev, sizeof(*pdma), GFP_KERNEL);
1876 	if (!pdma)
1877 		return -ENOMEM;
1878 
1879 	pdma->dev = &pdev->dev;
1880 	platform_set_drvdata(pdev, pdma);
1881 
1882 	ret = xgene_dma_get_resources(pdev, pdma);
1883 	if (ret)
1884 		return ret;
1885 
1886 	pdma->clk = devm_clk_get(&pdev->dev, NULL);
1887 	if (IS_ERR(pdma->clk) && !ACPI_COMPANION(&pdev->dev)) {
1888 		dev_err(&pdev->dev, "Failed to get clk\n");
1889 		return PTR_ERR(pdma->clk);
1890 	}
1891 
1892 	/* Enable clk before accessing registers */
1893 	if (!IS_ERR(pdma->clk)) {
1894 		ret = clk_prepare_enable(pdma->clk);
1895 		if (ret) {
1896 			dev_err(&pdev->dev, "Failed to enable clk %d\n", ret);
1897 			return ret;
1898 		}
1899 	}
1900 
1901 	/* Remove DMA RAM out of shutdown */
1902 	ret = xgene_dma_init_mem(pdma);
1903 	if (ret)
1904 		goto err_clk_enable;
1905 
1906 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(42));
1907 	if (ret) {
1908 		dev_err(&pdev->dev, "No usable DMA configuration\n");
1909 		goto err_dma_mask;
1910 	}
1911 
1912 	/* Initialize DMA channels software state */
1913 	xgene_dma_init_channels(pdma);
1914 
1915 	/* Configue DMA rings */
1916 	ret = xgene_dma_init_rings(pdma);
1917 	if (ret)
1918 		goto err_clk_enable;
1919 
1920 	ret = xgene_dma_request_irqs(pdma);
1921 	if (ret)
1922 		goto err_request_irq;
1923 
1924 	/* Configure and enable DMA engine */
1925 	xgene_dma_init_hw(pdma);
1926 
1927 	/* Register DMA device with linux async framework */
1928 	ret = xgene_dma_init_async(pdma);
1929 	if (ret)
1930 		goto err_async_init;
1931 
1932 	return 0;
1933 
1934 err_async_init:
1935 	xgene_dma_free_irqs(pdma);
1936 
1937 err_request_irq:
1938 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++)
1939 		xgene_dma_delete_chan_rings(&pdma->chan[i]);
1940 
1941 err_dma_mask:
1942 err_clk_enable:
1943 	if (!IS_ERR(pdma->clk))
1944 		clk_disable_unprepare(pdma->clk);
1945 
1946 	return ret;
1947 }
1948 
1949 static int xgene_dma_remove(struct platform_device *pdev)
1950 {
1951 	struct xgene_dma *pdma = platform_get_drvdata(pdev);
1952 	struct xgene_dma_chan *chan;
1953 	int i;
1954 
1955 	xgene_dma_async_unregister(pdma);
1956 
1957 	/* Mask interrupts and disable DMA engine */
1958 	xgene_dma_mask_interrupts(pdma);
1959 	xgene_dma_disable(pdma);
1960 	xgene_dma_free_irqs(pdma);
1961 
1962 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1963 		chan = &pdma->chan[i];
1964 		tasklet_kill(&chan->tasklet);
1965 		xgene_dma_delete_chan_rings(chan);
1966 	}
1967 
1968 	if (!IS_ERR(pdma->clk))
1969 		clk_disable_unprepare(pdma->clk);
1970 
1971 	return 0;
1972 }
1973 
1974 #ifdef CONFIG_ACPI
1975 static const struct acpi_device_id xgene_dma_acpi_match_ptr[] = {
1976 	{"APMC0D43", 0},
1977 	{},
1978 };
1979 MODULE_DEVICE_TABLE(acpi, xgene_dma_acpi_match_ptr);
1980 #endif
1981 
1982 static const struct of_device_id xgene_dma_of_match_ptr[] = {
1983 	{.compatible = "apm,xgene-storm-dma",},
1984 	{},
1985 };
1986 MODULE_DEVICE_TABLE(of, xgene_dma_of_match_ptr);
1987 
1988 static struct platform_driver xgene_dma_driver = {
1989 	.probe = xgene_dma_probe,
1990 	.remove = xgene_dma_remove,
1991 	.driver = {
1992 		.name = "X-Gene-DMA",
1993 		.of_match_table = xgene_dma_of_match_ptr,
1994 		.acpi_match_table = ACPI_PTR(xgene_dma_acpi_match_ptr),
1995 	},
1996 };
1997 
1998 module_platform_driver(xgene_dma_driver);
1999 
2000 MODULE_DESCRIPTION("APM X-Gene SoC DMA driver");
2001 MODULE_AUTHOR("Rameshwar Prasad Sahu <rsahu@apm.com>");
2002 MODULE_AUTHOR("Loc Ho <lho@apm.com>");
2003 MODULE_LICENSE("GPL");
2004 MODULE_VERSION("1.0");
2005