xref: /openbmc/linux/drivers/dma/xgene-dma.c (revision cb1aaebe)
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/irq.h>
33 #include <linux/module.h>
34 #include <linux/of_device.h>
35 
36 #include "dmaengine.h"
37 
38 /* X-Gene DMA ring csr registers and bit definations */
39 #define XGENE_DMA_RING_CONFIG			0x04
40 #define XGENE_DMA_RING_ENABLE			BIT(31)
41 #define XGENE_DMA_RING_ID			0x08
42 #define XGENE_DMA_RING_ID_SETUP(v)		((v) | BIT(31))
43 #define XGENE_DMA_RING_ID_BUF			0x0C
44 #define XGENE_DMA_RING_ID_BUF_SETUP(v)		(((v) << 9) | BIT(21))
45 #define XGENE_DMA_RING_THRESLD0_SET1		0x30
46 #define XGENE_DMA_RING_THRESLD0_SET1_VAL	0X64
47 #define XGENE_DMA_RING_THRESLD1_SET1		0x34
48 #define XGENE_DMA_RING_THRESLD1_SET1_VAL	0xC8
49 #define XGENE_DMA_RING_HYSTERESIS		0x68
50 #define XGENE_DMA_RING_HYSTERESIS_VAL		0xFFFFFFFF
51 #define XGENE_DMA_RING_STATE			0x6C
52 #define XGENE_DMA_RING_STATE_WR_BASE		0x70
53 #define XGENE_DMA_RING_NE_INT_MODE		0x017C
54 #define XGENE_DMA_RING_NE_INT_MODE_SET(m, v)	\
55 	((m) = ((m) & ~BIT(31 - (v))) | BIT(31 - (v)))
56 #define XGENE_DMA_RING_NE_INT_MODE_RESET(m, v)	\
57 	((m) &= (~BIT(31 - (v))))
58 #define XGENE_DMA_RING_CLKEN			0xC208
59 #define XGENE_DMA_RING_SRST			0xC200
60 #define XGENE_DMA_RING_MEM_RAM_SHUTDOWN		0xD070
61 #define XGENE_DMA_RING_BLK_MEM_RDY		0xD074
62 #define XGENE_DMA_RING_BLK_MEM_RDY_VAL		0xFFFFFFFF
63 #define XGENE_DMA_RING_ID_GET(owner, num)	(((owner) << 6) | (num))
64 #define XGENE_DMA_RING_DST_ID(v)		((1 << 10) | (v))
65 #define XGENE_DMA_RING_CMD_OFFSET		0x2C
66 #define XGENE_DMA_RING_CMD_BASE_OFFSET(v)	((v) << 6)
67 #define XGENE_DMA_RING_COHERENT_SET(m)		\
68 	(((u32 *)(m))[2] |= BIT(4))
69 #define XGENE_DMA_RING_ADDRL_SET(m, v)		\
70 	(((u32 *)(m))[2] |= (((v) >> 8) << 5))
71 #define XGENE_DMA_RING_ADDRH_SET(m, v)		\
72 	(((u32 *)(m))[3] |= ((v) >> 35))
73 #define XGENE_DMA_RING_ACCEPTLERR_SET(m)	\
74 	(((u32 *)(m))[3] |= BIT(19))
75 #define XGENE_DMA_RING_SIZE_SET(m, v)		\
76 	(((u32 *)(m))[3] |= ((v) << 23))
77 #define XGENE_DMA_RING_RECOMBBUF_SET(m)		\
78 	(((u32 *)(m))[3] |= BIT(27))
79 #define XGENE_DMA_RING_RECOMTIMEOUTL_SET(m)	\
80 	(((u32 *)(m))[3] |= (0x7 << 28))
81 #define XGENE_DMA_RING_RECOMTIMEOUTH_SET(m)	\
82 	(((u32 *)(m))[4] |= 0x3)
83 #define XGENE_DMA_RING_SELTHRSH_SET(m)		\
84 	(((u32 *)(m))[4] |= BIT(3))
85 #define XGENE_DMA_RING_TYPE_SET(m, v)		\
86 	(((u32 *)(m))[4] |= ((v) << 19))
87 
88 /* X-Gene DMA device csr registers and bit definitions */
89 #define XGENE_DMA_IPBRR				0x0
90 #define XGENE_DMA_DEV_ID_RD(v)			((v) & 0x00000FFF)
91 #define XGENE_DMA_BUS_ID_RD(v)			(((v) >> 12) & 3)
92 #define XGENE_DMA_REV_NO_RD(v)			(((v) >> 14) & 3)
93 #define XGENE_DMA_GCR				0x10
94 #define XGENE_DMA_CH_SETUP(v)			\
95 	((v) = ((v) & ~0x000FFFFF) | 0x000AAFFF)
96 #define XGENE_DMA_ENABLE(v)			((v) |= BIT(31))
97 #define XGENE_DMA_DISABLE(v)			((v) &= ~BIT(31))
98 #define XGENE_DMA_RAID6_CONT			0x14
99 #define XGENE_DMA_RAID6_MULTI_CTRL(v)		((v) << 24)
100 #define XGENE_DMA_INT				0x70
101 #define XGENE_DMA_INT_MASK			0x74
102 #define XGENE_DMA_INT_ALL_MASK			0xFFFFFFFF
103 #define XGENE_DMA_INT_ALL_UNMASK		0x0
104 #define XGENE_DMA_INT_MASK_SHIFT		0x14
105 #define XGENE_DMA_RING_INT0_MASK		0x90A0
106 #define XGENE_DMA_RING_INT1_MASK		0x90A8
107 #define XGENE_DMA_RING_INT2_MASK		0x90B0
108 #define XGENE_DMA_RING_INT3_MASK		0x90B8
109 #define XGENE_DMA_RING_INT4_MASK		0x90C0
110 #define XGENE_DMA_CFG_RING_WQ_ASSOC		0x90E0
111 #define XGENE_DMA_ASSOC_RING_MNGR1		0xFFFFFFFF
112 #define XGENE_DMA_MEM_RAM_SHUTDOWN		0xD070
113 #define XGENE_DMA_BLK_MEM_RDY			0xD074
114 #define XGENE_DMA_BLK_MEM_RDY_VAL		0xFFFFFFFF
115 #define XGENE_DMA_RING_CMD_SM_OFFSET		0x8000
116 
117 /* X-Gene SoC EFUSE csr register and bit defination */
118 #define XGENE_SOC_JTAG1_SHADOW			0x18
119 #define XGENE_DMA_PQ_DISABLE_MASK		BIT(13)
120 
121 /* X-Gene DMA Descriptor format */
122 #define XGENE_DMA_DESC_NV_BIT			BIT_ULL(50)
123 #define XGENE_DMA_DESC_IN_BIT			BIT_ULL(55)
124 #define XGENE_DMA_DESC_C_BIT			BIT_ULL(63)
125 #define XGENE_DMA_DESC_DR_BIT			BIT_ULL(61)
126 #define XGENE_DMA_DESC_ELERR_POS		46
127 #define XGENE_DMA_DESC_RTYPE_POS		56
128 #define XGENE_DMA_DESC_LERR_POS			60
129 #define XGENE_DMA_DESC_BUFLEN_POS		48
130 #define XGENE_DMA_DESC_HOENQ_NUM_POS		48
131 #define XGENE_DMA_DESC_ELERR_RD(m)		\
132 	(((m) >> XGENE_DMA_DESC_ELERR_POS) & 0x3)
133 #define XGENE_DMA_DESC_LERR_RD(m)		\
134 	(((m) >> XGENE_DMA_DESC_LERR_POS) & 0x7)
135 #define XGENE_DMA_DESC_STATUS(elerr, lerr)	\
136 	(((elerr) << 4) | (lerr))
137 
138 /* X-Gene DMA descriptor empty s/w signature */
139 #define XGENE_DMA_DESC_EMPTY_SIGNATURE		~0ULL
140 
141 /* X-Gene DMA configurable parameters defines */
142 #define XGENE_DMA_RING_NUM		512
143 #define XGENE_DMA_BUFNUM		0x0
144 #define XGENE_DMA_CPU_BUFNUM		0x18
145 #define XGENE_DMA_RING_OWNER_DMA	0x03
146 #define XGENE_DMA_RING_OWNER_CPU	0x0F
147 #define XGENE_DMA_RING_TYPE_REGULAR	0x01
148 #define XGENE_DMA_RING_WQ_DESC_SIZE	32	/* 32 Bytes */
149 #define XGENE_DMA_RING_NUM_CONFIG	5
150 #define XGENE_DMA_MAX_CHANNEL		4
151 #define XGENE_DMA_XOR_CHANNEL		0
152 #define XGENE_DMA_PQ_CHANNEL		1
153 #define XGENE_DMA_MAX_BYTE_CNT		0x4000	/* 16 KB */
154 #define XGENE_DMA_MAX_64B_DESC_BYTE_CNT	0x14000	/* 80 KB */
155 #define XGENE_DMA_MAX_XOR_SRC		5
156 #define XGENE_DMA_16K_BUFFER_LEN_CODE	0x0
157 #define XGENE_DMA_INVALID_LEN_CODE	0x7800000000000000ULL
158 
159 /* X-Gene DMA descriptor error codes */
160 #define ERR_DESC_AXI			0x01
161 #define ERR_BAD_DESC			0x02
162 #define ERR_READ_DATA_AXI		0x03
163 #define ERR_WRITE_DATA_AXI		0x04
164 #define ERR_FBP_TIMEOUT			0x05
165 #define ERR_ECC				0x06
166 #define ERR_DIFF_SIZE			0x08
167 #define ERR_SCT_GAT_LEN			0x09
168 #define ERR_CRC_ERR			0x11
169 #define ERR_CHKSUM			0x12
170 #define ERR_DIF				0x13
171 
172 /* X-Gene DMA error interrupt codes */
173 #define ERR_DIF_SIZE_INT		0x0
174 #define ERR_GS_ERR_INT			0x1
175 #define ERR_FPB_TIMEO_INT		0x2
176 #define ERR_WFIFO_OVF_INT		0x3
177 #define ERR_RFIFO_OVF_INT		0x4
178 #define ERR_WR_TIMEO_INT		0x5
179 #define ERR_RD_TIMEO_INT		0x6
180 #define ERR_WR_ERR_INT			0x7
181 #define ERR_RD_ERR_INT			0x8
182 #define ERR_BAD_DESC_INT		0x9
183 #define ERR_DESC_DST_INT		0xA
184 #define ERR_DESC_SRC_INT		0xB
185 
186 /* X-Gene DMA flyby operation code */
187 #define FLYBY_2SRC_XOR			0x80
188 #define FLYBY_3SRC_XOR			0x90
189 #define FLYBY_4SRC_XOR			0xA0
190 #define FLYBY_5SRC_XOR			0xB0
191 
192 /* X-Gene DMA SW descriptor flags */
193 #define XGENE_DMA_FLAG_64B_DESC		BIT(0)
194 
195 /* Define to dump X-Gene DMA descriptor */
196 #define XGENE_DMA_DESC_DUMP(desc, m)	\
197 	print_hex_dump(KERN_ERR, (m),	\
198 			DUMP_PREFIX_ADDRESS, 16, 8, (desc), 32, 0)
199 
200 #define to_dma_desc_sw(tx)		\
201 	container_of(tx, struct xgene_dma_desc_sw, tx)
202 #define to_dma_chan(dchan)		\
203 	container_of(dchan, struct xgene_dma_chan, dma_chan)
204 
205 #define chan_dbg(chan, fmt, arg...)	\
206 	dev_dbg(chan->dev, "%s: " fmt, chan->name, ##arg)
207 #define chan_err(chan, fmt, arg...)	\
208 	dev_err(chan->dev, "%s: " fmt, chan->name, ##arg)
209 
210 struct xgene_dma_desc_hw {
211 	__le64 m0;
212 	__le64 m1;
213 	__le64 m2;
214 	__le64 m3;
215 };
216 
217 enum xgene_dma_ring_cfgsize {
218 	XGENE_DMA_RING_CFG_SIZE_512B,
219 	XGENE_DMA_RING_CFG_SIZE_2KB,
220 	XGENE_DMA_RING_CFG_SIZE_16KB,
221 	XGENE_DMA_RING_CFG_SIZE_64KB,
222 	XGENE_DMA_RING_CFG_SIZE_512KB,
223 	XGENE_DMA_RING_CFG_SIZE_INVALID
224 };
225 
226 struct xgene_dma_ring {
227 	struct xgene_dma *pdma;
228 	u8 buf_num;
229 	u16 id;
230 	u16 num;
231 	u16 head;
232 	u16 owner;
233 	u16 slots;
234 	u16 dst_ring_num;
235 	u32 size;
236 	void __iomem *cmd;
237 	void __iomem *cmd_base;
238 	dma_addr_t desc_paddr;
239 	u32 state[XGENE_DMA_RING_NUM_CONFIG];
240 	enum xgene_dma_ring_cfgsize cfgsize;
241 	union {
242 		void *desc_vaddr;
243 		struct xgene_dma_desc_hw *desc_hw;
244 	};
245 };
246 
247 struct xgene_dma_desc_sw {
248 	struct xgene_dma_desc_hw desc1;
249 	struct xgene_dma_desc_hw desc2;
250 	u32 flags;
251 	struct list_head node;
252 	struct list_head tx_list;
253 	struct dma_async_tx_descriptor tx;
254 };
255 
256 /**
257  * struct xgene_dma_chan - internal representation of an X-Gene DMA channel
258  * @dma_chan: dmaengine channel object member
259  * @pdma: X-Gene DMA device structure reference
260  * @dev: struct device reference for dma mapping api
261  * @id: raw id of this channel
262  * @rx_irq: channel IRQ
263  * @name: name of X-Gene DMA channel
264  * @lock: serializes enqueue/dequeue operations to the descriptor pool
265  * @pending: number of transaction request pushed to DMA controller for
266  *	execution, but still waiting for completion,
267  * @max_outstanding: max number of outstanding request we can push to channel
268  * @ld_pending: descriptors which are queued to run, but have not yet been
269  *	submitted to the hardware for execution
270  * @ld_running: descriptors which are currently being executing by the hardware
271  * @ld_completed: descriptors which have finished execution by the hardware.
272  *	These descriptors have already had their cleanup actions run. They
273  *	are waiting for the ACK bit to be set by the async tx API.
274  * @desc_pool: descriptor pool for DMA operations
275  * @tasklet: bottom half where all completed descriptors cleans
276  * @tx_ring: transmit ring descriptor that we use to prepare actual
277  *	descriptors for further executions
278  * @rx_ring: receive ring descriptor that we use to get completed DMA
279  *	descriptors during cleanup time
280  */
281 struct xgene_dma_chan {
282 	struct dma_chan dma_chan;
283 	struct xgene_dma *pdma;
284 	struct device *dev;
285 	int id;
286 	int rx_irq;
287 	char name[10];
288 	spinlock_t lock;
289 	int pending;
290 	int max_outstanding;
291 	struct list_head ld_pending;
292 	struct list_head ld_running;
293 	struct list_head ld_completed;
294 	struct dma_pool *desc_pool;
295 	struct tasklet_struct tasklet;
296 	struct xgene_dma_ring tx_ring;
297 	struct xgene_dma_ring rx_ring;
298 };
299 
300 /**
301  * struct xgene_dma - internal representation of an X-Gene DMA device
302  * @err_irq: DMA error irq number
303  * @ring_num: start id number for DMA ring
304  * @csr_dma: base for DMA register access
305  * @csr_ring: base for DMA ring register access
306  * @csr_ring_cmd: base for DMA ring command register access
307  * @csr_efuse: base for efuse register access
308  * @dma_dev: embedded struct dma_device
309  * @chan: reference to X-Gene DMA channels
310  */
311 struct xgene_dma {
312 	struct device *dev;
313 	struct clk *clk;
314 	int err_irq;
315 	int ring_num;
316 	void __iomem *csr_dma;
317 	void __iomem *csr_ring;
318 	void __iomem *csr_ring_cmd;
319 	void __iomem *csr_efuse;
320 	struct dma_device dma_dev[XGENE_DMA_MAX_CHANNEL];
321 	struct xgene_dma_chan chan[XGENE_DMA_MAX_CHANNEL];
322 };
323 
324 static const char * const xgene_dma_desc_err[] = {
325 	[ERR_DESC_AXI] = "AXI error when reading src/dst link list",
326 	[ERR_BAD_DESC] = "ERR or El_ERR fields not set to zero in desc",
327 	[ERR_READ_DATA_AXI] = "AXI error when reading data",
328 	[ERR_WRITE_DATA_AXI] = "AXI error when writing data",
329 	[ERR_FBP_TIMEOUT] = "Timeout on bufpool fetch",
330 	[ERR_ECC] = "ECC double bit error",
331 	[ERR_DIFF_SIZE] = "Bufpool too small to hold all the DIF result",
332 	[ERR_SCT_GAT_LEN] = "Gather and scatter data length not same",
333 	[ERR_CRC_ERR] = "CRC error",
334 	[ERR_CHKSUM] = "Checksum error",
335 	[ERR_DIF] = "DIF error",
336 };
337 
338 static const char * const xgene_dma_err[] = {
339 	[ERR_DIF_SIZE_INT] = "DIF size error",
340 	[ERR_GS_ERR_INT] = "Gather scatter not same size error",
341 	[ERR_FPB_TIMEO_INT] = "Free pool time out error",
342 	[ERR_WFIFO_OVF_INT] = "Write FIFO over flow error",
343 	[ERR_RFIFO_OVF_INT] = "Read FIFO over flow error",
344 	[ERR_WR_TIMEO_INT] = "Write time out error",
345 	[ERR_RD_TIMEO_INT] = "Read time out error",
346 	[ERR_WR_ERR_INT] = "HBF bus write error",
347 	[ERR_RD_ERR_INT] = "HBF bus read error",
348 	[ERR_BAD_DESC_INT] = "Ring descriptor HE0 not set error",
349 	[ERR_DESC_DST_INT] = "HFB reading dst link address error",
350 	[ERR_DESC_SRC_INT] = "HFB reading src link address error",
351 };
352 
353 static bool is_pq_enabled(struct xgene_dma *pdma)
354 {
355 	u32 val;
356 
357 	val = ioread32(pdma->csr_efuse + XGENE_SOC_JTAG1_SHADOW);
358 	return !(val & XGENE_DMA_PQ_DISABLE_MASK);
359 }
360 
361 static u64 xgene_dma_encode_len(size_t len)
362 {
363 	return (len < XGENE_DMA_MAX_BYTE_CNT) ?
364 		((u64)len << XGENE_DMA_DESC_BUFLEN_POS) :
365 		XGENE_DMA_16K_BUFFER_LEN_CODE;
366 }
367 
368 static u8 xgene_dma_encode_xor_flyby(u32 src_cnt)
369 {
370 	static u8 flyby_type[] = {
371 		FLYBY_2SRC_XOR, /* Dummy */
372 		FLYBY_2SRC_XOR, /* Dummy */
373 		FLYBY_2SRC_XOR,
374 		FLYBY_3SRC_XOR,
375 		FLYBY_4SRC_XOR,
376 		FLYBY_5SRC_XOR
377 	};
378 
379 	return flyby_type[src_cnt];
380 }
381 
382 static void xgene_dma_set_src_buffer(__le64 *ext8, size_t *len,
383 				     dma_addr_t *paddr)
384 {
385 	size_t nbytes = (*len < XGENE_DMA_MAX_BYTE_CNT) ?
386 			*len : XGENE_DMA_MAX_BYTE_CNT;
387 
388 	*ext8 |= cpu_to_le64(*paddr);
389 	*ext8 |= cpu_to_le64(xgene_dma_encode_len(nbytes));
390 	*len -= nbytes;
391 	*paddr += nbytes;
392 }
393 
394 static __le64 *xgene_dma_lookup_ext8(struct xgene_dma_desc_hw *desc, int idx)
395 {
396 	switch (idx) {
397 	case 0:
398 		return &desc->m1;
399 	case 1:
400 		return &desc->m0;
401 	case 2:
402 		return &desc->m3;
403 	case 3:
404 		return &desc->m2;
405 	default:
406 		pr_err("Invalid dma descriptor index\n");
407 	}
408 
409 	return NULL;
410 }
411 
412 static void xgene_dma_init_desc(struct xgene_dma_desc_hw *desc,
413 				u16 dst_ring_num)
414 {
415 	desc->m0 |= cpu_to_le64(XGENE_DMA_DESC_IN_BIT);
416 	desc->m0 |= cpu_to_le64((u64)XGENE_DMA_RING_OWNER_DMA <<
417 				XGENE_DMA_DESC_RTYPE_POS);
418 	desc->m1 |= cpu_to_le64(XGENE_DMA_DESC_C_BIT);
419 	desc->m3 |= cpu_to_le64((u64)dst_ring_num <<
420 				XGENE_DMA_DESC_HOENQ_NUM_POS);
421 }
422 
423 static void xgene_dma_prep_xor_desc(struct xgene_dma_chan *chan,
424 				    struct xgene_dma_desc_sw *desc_sw,
425 				    dma_addr_t *dst, dma_addr_t *src,
426 				    u32 src_cnt, size_t *nbytes,
427 				    const u8 *scf)
428 {
429 	struct xgene_dma_desc_hw *desc1, *desc2;
430 	size_t len = *nbytes;
431 	int i;
432 
433 	desc1 = &desc_sw->desc1;
434 	desc2 = &desc_sw->desc2;
435 
436 	/* Initialize DMA descriptor */
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 	/* We have multiple source addresses, so need to set NV bit*/
444 	desc1->m0 |= cpu_to_le64(XGENE_DMA_DESC_NV_BIT);
445 
446 	/* Set flyby opcode */
447 	desc1->m2 |= cpu_to_le64(xgene_dma_encode_xor_flyby(src_cnt));
448 
449 	/* Set 1st to 5th source addresses */
450 	for (i = 0; i < src_cnt; i++) {
451 		len = *nbytes;
452 		xgene_dma_set_src_buffer((i == 0) ? &desc1->m1 :
453 					 xgene_dma_lookup_ext8(desc2, i - 1),
454 					 &len, &src[i]);
455 		desc1->m2 |= cpu_to_le64((scf[i] << ((i + 1) * 8)));
456 	}
457 
458 	/* Update meta data */
459 	*nbytes = len;
460 	*dst += XGENE_DMA_MAX_BYTE_CNT;
461 
462 	/* We need always 64B descriptor to perform xor or pq operations */
463 	desc_sw->flags |= XGENE_DMA_FLAG_64B_DESC;
464 }
465 
466 static dma_cookie_t xgene_dma_tx_submit(struct dma_async_tx_descriptor *tx)
467 {
468 	struct xgene_dma_desc_sw *desc;
469 	struct xgene_dma_chan *chan;
470 	dma_cookie_t cookie;
471 
472 	if (unlikely(!tx))
473 		return -EINVAL;
474 
475 	chan = to_dma_chan(tx->chan);
476 	desc = to_dma_desc_sw(tx);
477 
478 	spin_lock_bh(&chan->lock);
479 
480 	cookie = dma_cookie_assign(tx);
481 
482 	/* Add this transaction list onto the tail of the pending queue */
483 	list_splice_tail_init(&desc->tx_list, &chan->ld_pending);
484 
485 	spin_unlock_bh(&chan->lock);
486 
487 	return cookie;
488 }
489 
490 static void xgene_dma_clean_descriptor(struct xgene_dma_chan *chan,
491 				       struct xgene_dma_desc_sw *desc)
492 {
493 	list_del(&desc->node);
494 	chan_dbg(chan, "LD %p free\n", desc);
495 	dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
496 }
497 
498 static struct xgene_dma_desc_sw *xgene_dma_alloc_descriptor(
499 				 struct xgene_dma_chan *chan)
500 {
501 	struct xgene_dma_desc_sw *desc;
502 	dma_addr_t phys;
503 
504 	desc = dma_pool_zalloc(chan->desc_pool, GFP_NOWAIT, &phys);
505 	if (!desc) {
506 		chan_err(chan, "Failed to allocate LDs\n");
507 		return NULL;
508 	}
509 
510 	INIT_LIST_HEAD(&desc->tx_list);
511 	desc->tx.phys = phys;
512 	desc->tx.tx_submit = xgene_dma_tx_submit;
513 	dma_async_tx_descriptor_init(&desc->tx, &chan->dma_chan);
514 
515 	chan_dbg(chan, "LD %p allocated\n", desc);
516 
517 	return desc;
518 }
519 
520 /**
521  * xgene_dma_clean_completed_descriptor - free all descriptors which
522  * has been completed and acked
523  * @chan: X-Gene DMA channel
524  *
525  * This function is used on all completed and acked descriptors.
526  */
527 static void xgene_dma_clean_completed_descriptor(struct xgene_dma_chan *chan)
528 {
529 	struct xgene_dma_desc_sw *desc, *_desc;
530 
531 	/* Run the callback for each descriptor, in order */
532 	list_for_each_entry_safe(desc, _desc, &chan->ld_completed, node) {
533 		if (async_tx_test_ack(&desc->tx))
534 			xgene_dma_clean_descriptor(chan, desc);
535 	}
536 }
537 
538 /**
539  * xgene_dma_run_tx_complete_actions - cleanup a single link descriptor
540  * @chan: X-Gene DMA channel
541  * @desc: descriptor to cleanup and free
542  *
543  * This function is used on a descriptor which has been executed by the DMA
544  * controller. It will run any callbacks, submit any dependencies.
545  */
546 static void xgene_dma_run_tx_complete_actions(struct xgene_dma_chan *chan,
547 					      struct xgene_dma_desc_sw *desc)
548 {
549 	struct dma_async_tx_descriptor *tx = &desc->tx;
550 
551 	/*
552 	 * If this is not the last transaction in the group,
553 	 * then no need to complete cookie and run any callback as
554 	 * this is not the tx_descriptor which had been sent to caller
555 	 * of this DMA request
556 	 */
557 
558 	if (tx->cookie == 0)
559 		return;
560 
561 	dma_cookie_complete(tx);
562 	dma_descriptor_unmap(tx);
563 
564 	/* Run the link descriptor callback function */
565 	dmaengine_desc_get_callback_invoke(tx, NULL);
566 
567 	/* Run any dependencies */
568 	dma_run_dependencies(tx);
569 }
570 
571 /**
572  * xgene_dma_clean_running_descriptor - move the completed descriptor from
573  * ld_running to ld_completed
574  * @chan: X-Gene DMA channel
575  * @desc: the descriptor which is completed
576  *
577  * Free the descriptor directly if acked by async_tx api,
578  * else move it to queue ld_completed.
579  */
580 static void xgene_dma_clean_running_descriptor(struct xgene_dma_chan *chan,
581 					       struct xgene_dma_desc_sw *desc)
582 {
583 	/* Remove from the list of running transactions */
584 	list_del(&desc->node);
585 
586 	/*
587 	 * the client is allowed to attach dependent operations
588 	 * until 'ack' is set
589 	 */
590 	if (!async_tx_test_ack(&desc->tx)) {
591 		/*
592 		 * Move this descriptor to the list of descriptors which is
593 		 * completed, but still awaiting the 'ack' bit to be set.
594 		 */
595 		list_add_tail(&desc->node, &chan->ld_completed);
596 		return;
597 	}
598 
599 	chan_dbg(chan, "LD %p free\n", desc);
600 	dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
601 }
602 
603 static void xgene_chan_xfer_request(struct xgene_dma_chan *chan,
604 				    struct xgene_dma_desc_sw *desc_sw)
605 {
606 	struct xgene_dma_ring *ring = &chan->tx_ring;
607 	struct xgene_dma_desc_hw *desc_hw;
608 
609 	/* Get hw descriptor from DMA tx ring */
610 	desc_hw = &ring->desc_hw[ring->head];
611 
612 	/*
613 	 * Increment the head count to point next
614 	 * descriptor for next time
615 	 */
616 	if (++ring->head == ring->slots)
617 		ring->head = 0;
618 
619 	/* Copy prepared sw descriptor data to hw descriptor */
620 	memcpy(desc_hw, &desc_sw->desc1, sizeof(*desc_hw));
621 
622 	/*
623 	 * Check if we have prepared 64B descriptor,
624 	 * in this case we need one more hw descriptor
625 	 */
626 	if (desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) {
627 		desc_hw = &ring->desc_hw[ring->head];
628 
629 		if (++ring->head == ring->slots)
630 			ring->head = 0;
631 
632 		memcpy(desc_hw, &desc_sw->desc2, sizeof(*desc_hw));
633 	}
634 
635 	/* Increment the pending transaction count */
636 	chan->pending += ((desc_sw->flags &
637 			  XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
638 
639 	/* Notify the hw that we have descriptor ready for execution */
640 	iowrite32((desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) ?
641 		  2 : 1, ring->cmd);
642 }
643 
644 /**
645  * xgene_chan_xfer_ld_pending - push any pending transactions to hw
646  * @chan : X-Gene DMA channel
647  *
648  * LOCKING: must hold chan->lock
649  */
650 static void xgene_chan_xfer_ld_pending(struct xgene_dma_chan *chan)
651 {
652 	struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
653 
654 	/*
655 	 * If the list of pending descriptors is empty, then we
656 	 * don't need to do any work at all
657 	 */
658 	if (list_empty(&chan->ld_pending)) {
659 		chan_dbg(chan, "No pending LDs\n");
660 		return;
661 	}
662 
663 	/*
664 	 * Move elements from the queue of pending transactions onto the list
665 	 * of running transactions and push it to hw for further executions
666 	 */
667 	list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_pending, node) {
668 		/*
669 		 * Check if have pushed max number of transactions to hw
670 		 * as capable, so let's stop here and will push remaining
671 		 * elements from pening ld queue after completing some
672 		 * descriptors that we have already pushed
673 		 */
674 		if (chan->pending >= chan->max_outstanding)
675 			return;
676 
677 		xgene_chan_xfer_request(chan, desc_sw);
678 
679 		/*
680 		 * Delete this element from ld pending queue and append it to
681 		 * ld running queue
682 		 */
683 		list_move_tail(&desc_sw->node, &chan->ld_running);
684 	}
685 }
686 
687 /**
688  * xgene_dma_cleanup_descriptors - cleanup link descriptors which are completed
689  * and move them to ld_completed to free until flag 'ack' is set
690  * @chan: X-Gene DMA channel
691  *
692  * This function is used on descriptors which have been executed by the DMA
693  * controller. It will run any callbacks, submit any dependencies, then
694  * free these descriptors if flag 'ack' is set.
695  */
696 static void xgene_dma_cleanup_descriptors(struct xgene_dma_chan *chan)
697 {
698 	struct xgene_dma_ring *ring = &chan->rx_ring;
699 	struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
700 	struct xgene_dma_desc_hw *desc_hw;
701 	struct list_head ld_completed;
702 	u8 status;
703 
704 	INIT_LIST_HEAD(&ld_completed);
705 
706 	spin_lock(&chan->lock);
707 
708 	/* Clean already completed and acked descriptors */
709 	xgene_dma_clean_completed_descriptor(chan);
710 
711 	/* Move all completed descriptors to ld completed queue, in order */
712 	list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_running, node) {
713 		/* Get subsequent hw descriptor from DMA rx ring */
714 		desc_hw = &ring->desc_hw[ring->head];
715 
716 		/* Check if this descriptor has been completed */
717 		if (unlikely(le64_to_cpu(desc_hw->m0) ==
718 			     XGENE_DMA_DESC_EMPTY_SIGNATURE))
719 			break;
720 
721 		if (++ring->head == ring->slots)
722 			ring->head = 0;
723 
724 		/* Check if we have any error with DMA transactions */
725 		status = XGENE_DMA_DESC_STATUS(
726 				XGENE_DMA_DESC_ELERR_RD(le64_to_cpu(
727 							desc_hw->m0)),
728 				XGENE_DMA_DESC_LERR_RD(le64_to_cpu(
729 						       desc_hw->m0)));
730 		if (status) {
731 			/* Print the DMA error type */
732 			chan_err(chan, "%s\n", xgene_dma_desc_err[status]);
733 
734 			/*
735 			 * We have DMA transactions error here. Dump DMA Tx
736 			 * and Rx descriptors for this request */
737 			XGENE_DMA_DESC_DUMP(&desc_sw->desc1,
738 					    "X-Gene DMA TX DESC1: ");
739 
740 			if (desc_sw->flags & XGENE_DMA_FLAG_64B_DESC)
741 				XGENE_DMA_DESC_DUMP(&desc_sw->desc2,
742 						    "X-Gene DMA TX DESC2: ");
743 
744 			XGENE_DMA_DESC_DUMP(desc_hw,
745 					    "X-Gene DMA RX ERR DESC: ");
746 		}
747 
748 		/* Notify the hw about this completed descriptor */
749 		iowrite32(-1, ring->cmd);
750 
751 		/* Mark this hw descriptor as processed */
752 		desc_hw->m0 = cpu_to_le64(XGENE_DMA_DESC_EMPTY_SIGNATURE);
753 
754 		/*
755 		 * Decrement the pending transaction count
756 		 * as we have processed one
757 		 */
758 		chan->pending -= ((desc_sw->flags &
759 				  XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
760 
761 		/*
762 		 * Delete this node from ld running queue and append it to
763 		 * ld completed queue for further processing
764 		 */
765 		list_move_tail(&desc_sw->node, &ld_completed);
766 	}
767 
768 	/*
769 	 * Start any pending transactions automatically
770 	 * In the ideal case, we keep the DMA controller busy while we go
771 	 * ahead and free the descriptors below.
772 	 */
773 	xgene_chan_xfer_ld_pending(chan);
774 
775 	spin_unlock(&chan->lock);
776 
777 	/* Run the callback for each descriptor, in order */
778 	list_for_each_entry_safe(desc_sw, _desc_sw, &ld_completed, node) {
779 		xgene_dma_run_tx_complete_actions(chan, desc_sw);
780 		xgene_dma_clean_running_descriptor(chan, desc_sw);
781 	}
782 }
783 
784 static int xgene_dma_alloc_chan_resources(struct dma_chan *dchan)
785 {
786 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
787 
788 	/* Has this channel already been allocated? */
789 	if (chan->desc_pool)
790 		return 1;
791 
792 	chan->desc_pool = dma_pool_create(chan->name, chan->dev,
793 					  sizeof(struct xgene_dma_desc_sw),
794 					  0, 0);
795 	if (!chan->desc_pool) {
796 		chan_err(chan, "Failed to allocate descriptor pool\n");
797 		return -ENOMEM;
798 	}
799 
800 	chan_dbg(chan, "Allocate descriptor pool\n");
801 
802 	return 1;
803 }
804 
805 /**
806  * xgene_dma_free_desc_list - Free all descriptors in a queue
807  * @chan: X-Gene DMA channel
808  * @list: the list to free
809  *
810  * LOCKING: must hold chan->lock
811  */
812 static void xgene_dma_free_desc_list(struct xgene_dma_chan *chan,
813 				     struct list_head *list)
814 {
815 	struct xgene_dma_desc_sw *desc, *_desc;
816 
817 	list_for_each_entry_safe(desc, _desc, list, node)
818 		xgene_dma_clean_descriptor(chan, desc);
819 }
820 
821 static void xgene_dma_free_chan_resources(struct dma_chan *dchan)
822 {
823 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
824 
825 	chan_dbg(chan, "Free all resources\n");
826 
827 	if (!chan->desc_pool)
828 		return;
829 
830 	/* Process all running descriptor */
831 	xgene_dma_cleanup_descriptors(chan);
832 
833 	spin_lock_bh(&chan->lock);
834 
835 	/* Clean all link descriptor queues */
836 	xgene_dma_free_desc_list(chan, &chan->ld_pending);
837 	xgene_dma_free_desc_list(chan, &chan->ld_running);
838 	xgene_dma_free_desc_list(chan, &chan->ld_completed);
839 
840 	spin_unlock_bh(&chan->lock);
841 
842 	/* Delete this channel DMA pool */
843 	dma_pool_destroy(chan->desc_pool);
844 	chan->desc_pool = NULL;
845 }
846 
847 static struct dma_async_tx_descriptor *xgene_dma_prep_xor(
848 	struct dma_chan *dchan, dma_addr_t dst,	dma_addr_t *src,
849 	u32 src_cnt, size_t len, unsigned long flags)
850 {
851 	struct xgene_dma_desc_sw *first = NULL, *new;
852 	struct xgene_dma_chan *chan;
853 	static u8 multi[XGENE_DMA_MAX_XOR_SRC] = {
854 				0x01, 0x01, 0x01, 0x01, 0x01};
855 
856 	if (unlikely(!dchan || !len))
857 		return NULL;
858 
859 	chan = to_dma_chan(dchan);
860 
861 	do {
862 		/* Allocate the link descriptor from DMA pool */
863 		new = xgene_dma_alloc_descriptor(chan);
864 		if (!new)
865 			goto fail;
866 
867 		/* Prepare xor DMA descriptor */
868 		xgene_dma_prep_xor_desc(chan, new, &dst, src,
869 					src_cnt, &len, multi);
870 
871 		if (!first)
872 			first = new;
873 
874 		new->tx.cookie = 0;
875 		async_tx_ack(&new->tx);
876 
877 		/* Insert the link descriptor to the LD ring */
878 		list_add_tail(&new->node, &first->tx_list);
879 	} while (len);
880 
881 	new->tx.flags = flags; /* client is in control of this ack */
882 	new->tx.cookie = -EBUSY;
883 	list_splice(&first->tx_list, &new->tx_list);
884 
885 	return &new->tx;
886 
887 fail:
888 	if (!first)
889 		return NULL;
890 
891 	xgene_dma_free_desc_list(chan, &first->tx_list);
892 	return NULL;
893 }
894 
895 static struct dma_async_tx_descriptor *xgene_dma_prep_pq(
896 	struct dma_chan *dchan, dma_addr_t *dst, dma_addr_t *src,
897 	u32 src_cnt, const u8 *scf, size_t len, unsigned long flags)
898 {
899 	struct xgene_dma_desc_sw *first = NULL, *new;
900 	struct xgene_dma_chan *chan;
901 	size_t _len = len;
902 	dma_addr_t _src[XGENE_DMA_MAX_XOR_SRC];
903 	static u8 multi[XGENE_DMA_MAX_XOR_SRC] = {0x01, 0x01, 0x01, 0x01, 0x01};
904 
905 	if (unlikely(!dchan || !len))
906 		return NULL;
907 
908 	chan = to_dma_chan(dchan);
909 
910 	/*
911 	 * Save source addresses on local variable, may be we have to
912 	 * prepare two descriptor to generate P and Q if both enabled
913 	 * in the flags by client
914 	 */
915 	memcpy(_src, src, sizeof(*src) * src_cnt);
916 
917 	if (flags & DMA_PREP_PQ_DISABLE_P)
918 		len = 0;
919 
920 	if (flags & DMA_PREP_PQ_DISABLE_Q)
921 		_len = 0;
922 
923 	do {
924 		/* Allocate the link descriptor from DMA pool */
925 		new = xgene_dma_alloc_descriptor(chan);
926 		if (!new)
927 			goto fail;
928 
929 		if (!first)
930 			first = new;
931 
932 		new->tx.cookie = 0;
933 		async_tx_ack(&new->tx);
934 
935 		/* Insert the link descriptor to the LD ring */
936 		list_add_tail(&new->node, &first->tx_list);
937 
938 		/*
939 		 * Prepare DMA descriptor to generate P,
940 		 * if DMA_PREP_PQ_DISABLE_P flag is not set
941 		 */
942 		if (len) {
943 			xgene_dma_prep_xor_desc(chan, new, &dst[0], src,
944 						src_cnt, &len, multi);
945 			continue;
946 		}
947 
948 		/*
949 		 * Prepare DMA descriptor to generate Q,
950 		 * if DMA_PREP_PQ_DISABLE_Q flag is not set
951 		 */
952 		if (_len) {
953 			xgene_dma_prep_xor_desc(chan, new, &dst[1], _src,
954 						src_cnt, &_len, scf);
955 		}
956 	} while (len || _len);
957 
958 	new->tx.flags = flags; /* client is in control of this ack */
959 	new->tx.cookie = -EBUSY;
960 	list_splice(&first->tx_list, &new->tx_list);
961 
962 	return &new->tx;
963 
964 fail:
965 	if (!first)
966 		return NULL;
967 
968 	xgene_dma_free_desc_list(chan, &first->tx_list);
969 	return NULL;
970 }
971 
972 static void xgene_dma_issue_pending(struct dma_chan *dchan)
973 {
974 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
975 
976 	spin_lock_bh(&chan->lock);
977 	xgene_chan_xfer_ld_pending(chan);
978 	spin_unlock_bh(&chan->lock);
979 }
980 
981 static enum dma_status xgene_dma_tx_status(struct dma_chan *dchan,
982 					   dma_cookie_t cookie,
983 					   struct dma_tx_state *txstate)
984 {
985 	return dma_cookie_status(dchan, cookie, txstate);
986 }
987 
988 static void xgene_dma_tasklet_cb(unsigned long data)
989 {
990 	struct xgene_dma_chan *chan = (struct xgene_dma_chan *)data;
991 
992 	/* Run all cleanup for descriptors which have been completed */
993 	xgene_dma_cleanup_descriptors(chan);
994 
995 	/* Re-enable DMA channel IRQ */
996 	enable_irq(chan->rx_irq);
997 }
998 
999 static irqreturn_t xgene_dma_chan_ring_isr(int irq, void *id)
1000 {
1001 	struct xgene_dma_chan *chan = (struct xgene_dma_chan *)id;
1002 
1003 	BUG_ON(!chan);
1004 
1005 	/*
1006 	 * Disable DMA channel IRQ until we process completed
1007 	 * descriptors
1008 	 */
1009 	disable_irq_nosync(chan->rx_irq);
1010 
1011 	/*
1012 	 * Schedule the tasklet to handle all cleanup of the current
1013 	 * transaction. It will start a new transaction if there is
1014 	 * one pending.
1015 	 */
1016 	tasklet_schedule(&chan->tasklet);
1017 
1018 	return IRQ_HANDLED;
1019 }
1020 
1021 static irqreturn_t xgene_dma_err_isr(int irq, void *id)
1022 {
1023 	struct xgene_dma *pdma = (struct xgene_dma *)id;
1024 	unsigned long int_mask;
1025 	u32 val, i;
1026 
1027 	val = ioread32(pdma->csr_dma + XGENE_DMA_INT);
1028 
1029 	/* Clear DMA interrupts */
1030 	iowrite32(val, pdma->csr_dma + XGENE_DMA_INT);
1031 
1032 	/* Print DMA error info */
1033 	int_mask = val >> XGENE_DMA_INT_MASK_SHIFT;
1034 	for_each_set_bit(i, &int_mask, ARRAY_SIZE(xgene_dma_err))
1035 		dev_err(pdma->dev,
1036 			"Interrupt status 0x%08X %s\n", val, xgene_dma_err[i]);
1037 
1038 	return IRQ_HANDLED;
1039 }
1040 
1041 static void xgene_dma_wr_ring_state(struct xgene_dma_ring *ring)
1042 {
1043 	int i;
1044 
1045 	iowrite32(ring->num, ring->pdma->csr_ring + XGENE_DMA_RING_STATE);
1046 
1047 	for (i = 0; i < XGENE_DMA_RING_NUM_CONFIG; i++)
1048 		iowrite32(ring->state[i], ring->pdma->csr_ring +
1049 			  XGENE_DMA_RING_STATE_WR_BASE + (i * 4));
1050 }
1051 
1052 static void xgene_dma_clr_ring_state(struct xgene_dma_ring *ring)
1053 {
1054 	memset(ring->state, 0, sizeof(u32) * XGENE_DMA_RING_NUM_CONFIG);
1055 	xgene_dma_wr_ring_state(ring);
1056 }
1057 
1058 static void xgene_dma_setup_ring(struct xgene_dma_ring *ring)
1059 {
1060 	void *ring_cfg = ring->state;
1061 	u64 addr = ring->desc_paddr;
1062 	u32 i, val;
1063 
1064 	ring->slots = ring->size / XGENE_DMA_RING_WQ_DESC_SIZE;
1065 
1066 	/* Clear DMA ring state */
1067 	xgene_dma_clr_ring_state(ring);
1068 
1069 	/* Set DMA ring type */
1070 	XGENE_DMA_RING_TYPE_SET(ring_cfg, XGENE_DMA_RING_TYPE_REGULAR);
1071 
1072 	if (ring->owner == XGENE_DMA_RING_OWNER_DMA) {
1073 		/* Set recombination buffer and timeout */
1074 		XGENE_DMA_RING_RECOMBBUF_SET(ring_cfg);
1075 		XGENE_DMA_RING_RECOMTIMEOUTL_SET(ring_cfg);
1076 		XGENE_DMA_RING_RECOMTIMEOUTH_SET(ring_cfg);
1077 	}
1078 
1079 	/* Initialize DMA ring state */
1080 	XGENE_DMA_RING_SELTHRSH_SET(ring_cfg);
1081 	XGENE_DMA_RING_ACCEPTLERR_SET(ring_cfg);
1082 	XGENE_DMA_RING_COHERENT_SET(ring_cfg);
1083 	XGENE_DMA_RING_ADDRL_SET(ring_cfg, addr);
1084 	XGENE_DMA_RING_ADDRH_SET(ring_cfg, addr);
1085 	XGENE_DMA_RING_SIZE_SET(ring_cfg, ring->cfgsize);
1086 
1087 	/* Write DMA ring configurations */
1088 	xgene_dma_wr_ring_state(ring);
1089 
1090 	/* Set DMA ring id */
1091 	iowrite32(XGENE_DMA_RING_ID_SETUP(ring->id),
1092 		  ring->pdma->csr_ring + XGENE_DMA_RING_ID);
1093 
1094 	/* Set DMA ring buffer */
1095 	iowrite32(XGENE_DMA_RING_ID_BUF_SETUP(ring->num),
1096 		  ring->pdma->csr_ring + XGENE_DMA_RING_ID_BUF);
1097 
1098 	if (ring->owner != XGENE_DMA_RING_OWNER_CPU)
1099 		return;
1100 
1101 	/* Set empty signature to DMA Rx ring descriptors */
1102 	for (i = 0; i < ring->slots; i++) {
1103 		struct xgene_dma_desc_hw *desc;
1104 
1105 		desc = &ring->desc_hw[i];
1106 		desc->m0 = cpu_to_le64(XGENE_DMA_DESC_EMPTY_SIGNATURE);
1107 	}
1108 
1109 	/* Enable DMA Rx ring interrupt */
1110 	val = ioread32(ring->pdma->csr_ring + XGENE_DMA_RING_NE_INT_MODE);
1111 	XGENE_DMA_RING_NE_INT_MODE_SET(val, ring->buf_num);
1112 	iowrite32(val, ring->pdma->csr_ring + XGENE_DMA_RING_NE_INT_MODE);
1113 }
1114 
1115 static void xgene_dma_clear_ring(struct xgene_dma_ring *ring)
1116 {
1117 	u32 ring_id, val;
1118 
1119 	if (ring->owner == XGENE_DMA_RING_OWNER_CPU) {
1120 		/* Disable DMA Rx ring interrupt */
1121 		val = ioread32(ring->pdma->csr_ring +
1122 			       XGENE_DMA_RING_NE_INT_MODE);
1123 		XGENE_DMA_RING_NE_INT_MODE_RESET(val, ring->buf_num);
1124 		iowrite32(val, ring->pdma->csr_ring +
1125 			  XGENE_DMA_RING_NE_INT_MODE);
1126 	}
1127 
1128 	/* Clear DMA ring state */
1129 	ring_id = XGENE_DMA_RING_ID_SETUP(ring->id);
1130 	iowrite32(ring_id, ring->pdma->csr_ring + XGENE_DMA_RING_ID);
1131 
1132 	iowrite32(0, ring->pdma->csr_ring + XGENE_DMA_RING_ID_BUF);
1133 	xgene_dma_clr_ring_state(ring);
1134 }
1135 
1136 static void xgene_dma_set_ring_cmd(struct xgene_dma_ring *ring)
1137 {
1138 	ring->cmd_base = ring->pdma->csr_ring_cmd +
1139 				XGENE_DMA_RING_CMD_BASE_OFFSET((ring->num -
1140 							  XGENE_DMA_RING_NUM));
1141 
1142 	ring->cmd = ring->cmd_base + XGENE_DMA_RING_CMD_OFFSET;
1143 }
1144 
1145 static int xgene_dma_get_ring_size(struct xgene_dma_chan *chan,
1146 				   enum xgene_dma_ring_cfgsize cfgsize)
1147 {
1148 	int size;
1149 
1150 	switch (cfgsize) {
1151 	case XGENE_DMA_RING_CFG_SIZE_512B:
1152 		size = 0x200;
1153 		break;
1154 	case XGENE_DMA_RING_CFG_SIZE_2KB:
1155 		size = 0x800;
1156 		break;
1157 	case XGENE_DMA_RING_CFG_SIZE_16KB:
1158 		size = 0x4000;
1159 		break;
1160 	case XGENE_DMA_RING_CFG_SIZE_64KB:
1161 		size = 0x10000;
1162 		break;
1163 	case XGENE_DMA_RING_CFG_SIZE_512KB:
1164 		size = 0x80000;
1165 		break;
1166 	default:
1167 		chan_err(chan, "Unsupported cfg ring size %d\n", cfgsize);
1168 		return -EINVAL;
1169 	}
1170 
1171 	return size;
1172 }
1173 
1174 static void xgene_dma_delete_ring_one(struct xgene_dma_ring *ring)
1175 {
1176 	/* Clear DMA ring configurations */
1177 	xgene_dma_clear_ring(ring);
1178 
1179 	/* De-allocate DMA ring descriptor */
1180 	if (ring->desc_vaddr) {
1181 		dma_free_coherent(ring->pdma->dev, ring->size,
1182 				  ring->desc_vaddr, ring->desc_paddr);
1183 		ring->desc_vaddr = NULL;
1184 	}
1185 }
1186 
1187 static void xgene_dma_delete_chan_rings(struct xgene_dma_chan *chan)
1188 {
1189 	xgene_dma_delete_ring_one(&chan->rx_ring);
1190 	xgene_dma_delete_ring_one(&chan->tx_ring);
1191 }
1192 
1193 static int xgene_dma_create_ring_one(struct xgene_dma_chan *chan,
1194 				     struct xgene_dma_ring *ring,
1195 				     enum xgene_dma_ring_cfgsize cfgsize)
1196 {
1197 	int ret;
1198 
1199 	/* Setup DMA ring descriptor variables */
1200 	ring->pdma = chan->pdma;
1201 	ring->cfgsize = cfgsize;
1202 	ring->num = chan->pdma->ring_num++;
1203 	ring->id = XGENE_DMA_RING_ID_GET(ring->owner, ring->buf_num);
1204 
1205 	ret = xgene_dma_get_ring_size(chan, cfgsize);
1206 	if (ret <= 0)
1207 		return ret;
1208 	ring->size = ret;
1209 
1210 	/* Allocate memory for DMA ring descriptor */
1211 	ring->desc_vaddr = dma_alloc_coherent(chan->dev, ring->size,
1212 					      &ring->desc_paddr, GFP_KERNEL);
1213 	if (!ring->desc_vaddr) {
1214 		chan_err(chan, "Failed to allocate ring desc\n");
1215 		return -ENOMEM;
1216 	}
1217 
1218 	/* Configure and enable DMA ring */
1219 	xgene_dma_set_ring_cmd(ring);
1220 	xgene_dma_setup_ring(ring);
1221 
1222 	return 0;
1223 }
1224 
1225 static int xgene_dma_create_chan_rings(struct xgene_dma_chan *chan)
1226 {
1227 	struct xgene_dma_ring *rx_ring = &chan->rx_ring;
1228 	struct xgene_dma_ring *tx_ring = &chan->tx_ring;
1229 	int ret;
1230 
1231 	/* Create DMA Rx ring descriptor */
1232 	rx_ring->owner = XGENE_DMA_RING_OWNER_CPU;
1233 	rx_ring->buf_num = XGENE_DMA_CPU_BUFNUM + chan->id;
1234 
1235 	ret = xgene_dma_create_ring_one(chan, rx_ring,
1236 					XGENE_DMA_RING_CFG_SIZE_64KB);
1237 	if (ret)
1238 		return ret;
1239 
1240 	chan_dbg(chan, "Rx ring id 0x%X num %d desc 0x%p\n",
1241 		 rx_ring->id, rx_ring->num, rx_ring->desc_vaddr);
1242 
1243 	/* Create DMA Tx ring descriptor */
1244 	tx_ring->owner = XGENE_DMA_RING_OWNER_DMA;
1245 	tx_ring->buf_num = XGENE_DMA_BUFNUM + chan->id;
1246 
1247 	ret = xgene_dma_create_ring_one(chan, tx_ring,
1248 					XGENE_DMA_RING_CFG_SIZE_64KB);
1249 	if (ret) {
1250 		xgene_dma_delete_ring_one(rx_ring);
1251 		return ret;
1252 	}
1253 
1254 	tx_ring->dst_ring_num = XGENE_DMA_RING_DST_ID(rx_ring->num);
1255 
1256 	chan_dbg(chan,
1257 		 "Tx ring id 0x%X num %d desc 0x%p\n",
1258 		 tx_ring->id, tx_ring->num, tx_ring->desc_vaddr);
1259 
1260 	/* Set the max outstanding request possible to this channel */
1261 	chan->max_outstanding = tx_ring->slots;
1262 
1263 	return ret;
1264 }
1265 
1266 static int xgene_dma_init_rings(struct xgene_dma *pdma)
1267 {
1268 	int ret, i, j;
1269 
1270 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1271 		ret = xgene_dma_create_chan_rings(&pdma->chan[i]);
1272 		if (ret) {
1273 			for (j = 0; j < i; j++)
1274 				xgene_dma_delete_chan_rings(&pdma->chan[j]);
1275 			return ret;
1276 		}
1277 	}
1278 
1279 	return ret;
1280 }
1281 
1282 static void xgene_dma_enable(struct xgene_dma *pdma)
1283 {
1284 	u32 val;
1285 
1286 	/* Configure and enable DMA engine */
1287 	val = ioread32(pdma->csr_dma + XGENE_DMA_GCR);
1288 	XGENE_DMA_CH_SETUP(val);
1289 	XGENE_DMA_ENABLE(val);
1290 	iowrite32(val, pdma->csr_dma + XGENE_DMA_GCR);
1291 }
1292 
1293 static void xgene_dma_disable(struct xgene_dma *pdma)
1294 {
1295 	u32 val;
1296 
1297 	val = ioread32(pdma->csr_dma + XGENE_DMA_GCR);
1298 	XGENE_DMA_DISABLE(val);
1299 	iowrite32(val, pdma->csr_dma + XGENE_DMA_GCR);
1300 }
1301 
1302 static void xgene_dma_mask_interrupts(struct xgene_dma *pdma)
1303 {
1304 	/*
1305 	 * Mask DMA ring overflow, underflow and
1306 	 * AXI write/read error interrupts
1307 	 */
1308 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1309 		  pdma->csr_dma + XGENE_DMA_RING_INT0_MASK);
1310 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1311 		  pdma->csr_dma + XGENE_DMA_RING_INT1_MASK);
1312 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1313 		  pdma->csr_dma + XGENE_DMA_RING_INT2_MASK);
1314 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1315 		  pdma->csr_dma + XGENE_DMA_RING_INT3_MASK);
1316 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1317 		  pdma->csr_dma + XGENE_DMA_RING_INT4_MASK);
1318 
1319 	/* Mask DMA error interrupts */
1320 	iowrite32(XGENE_DMA_INT_ALL_MASK, pdma->csr_dma + XGENE_DMA_INT_MASK);
1321 }
1322 
1323 static void xgene_dma_unmask_interrupts(struct xgene_dma *pdma)
1324 {
1325 	/*
1326 	 * Unmask DMA ring overflow, underflow and
1327 	 * AXI write/read error interrupts
1328 	 */
1329 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1330 		  pdma->csr_dma + XGENE_DMA_RING_INT0_MASK);
1331 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1332 		  pdma->csr_dma + XGENE_DMA_RING_INT1_MASK);
1333 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1334 		  pdma->csr_dma + XGENE_DMA_RING_INT2_MASK);
1335 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1336 		  pdma->csr_dma + XGENE_DMA_RING_INT3_MASK);
1337 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1338 		  pdma->csr_dma + XGENE_DMA_RING_INT4_MASK);
1339 
1340 	/* Unmask DMA error interrupts */
1341 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1342 		  pdma->csr_dma + XGENE_DMA_INT_MASK);
1343 }
1344 
1345 static void xgene_dma_init_hw(struct xgene_dma *pdma)
1346 {
1347 	u32 val;
1348 
1349 	/* Associate DMA ring to corresponding ring HW */
1350 	iowrite32(XGENE_DMA_ASSOC_RING_MNGR1,
1351 		  pdma->csr_dma + XGENE_DMA_CFG_RING_WQ_ASSOC);
1352 
1353 	/* Configure RAID6 polynomial control setting */
1354 	if (is_pq_enabled(pdma))
1355 		iowrite32(XGENE_DMA_RAID6_MULTI_CTRL(0x1D),
1356 			  pdma->csr_dma + XGENE_DMA_RAID6_CONT);
1357 	else
1358 		dev_info(pdma->dev, "PQ is disabled in HW\n");
1359 
1360 	xgene_dma_enable(pdma);
1361 	xgene_dma_unmask_interrupts(pdma);
1362 
1363 	/* Get DMA id and version info */
1364 	val = ioread32(pdma->csr_dma + XGENE_DMA_IPBRR);
1365 
1366 	/* DMA device info */
1367 	dev_info(pdma->dev,
1368 		 "X-Gene DMA v%d.%02d.%02d driver registered %d channels",
1369 		 XGENE_DMA_REV_NO_RD(val), XGENE_DMA_BUS_ID_RD(val),
1370 		 XGENE_DMA_DEV_ID_RD(val), XGENE_DMA_MAX_CHANNEL);
1371 }
1372 
1373 static int xgene_dma_init_ring_mngr(struct xgene_dma *pdma)
1374 {
1375 	if (ioread32(pdma->csr_ring + XGENE_DMA_RING_CLKEN) &&
1376 	    (!ioread32(pdma->csr_ring + XGENE_DMA_RING_SRST)))
1377 		return 0;
1378 
1379 	iowrite32(0x3, pdma->csr_ring + XGENE_DMA_RING_CLKEN);
1380 	iowrite32(0x0, pdma->csr_ring + XGENE_DMA_RING_SRST);
1381 
1382 	/* Bring up memory */
1383 	iowrite32(0x0, pdma->csr_ring + XGENE_DMA_RING_MEM_RAM_SHUTDOWN);
1384 
1385 	/* Force a barrier */
1386 	ioread32(pdma->csr_ring + XGENE_DMA_RING_MEM_RAM_SHUTDOWN);
1387 
1388 	/* reset may take up to 1ms */
1389 	usleep_range(1000, 1100);
1390 
1391 	if (ioread32(pdma->csr_ring + XGENE_DMA_RING_BLK_MEM_RDY)
1392 		!= XGENE_DMA_RING_BLK_MEM_RDY_VAL) {
1393 		dev_err(pdma->dev,
1394 			"Failed to release ring mngr memory from shutdown\n");
1395 		return -ENODEV;
1396 	}
1397 
1398 	/* program threshold set 1 and all hysteresis */
1399 	iowrite32(XGENE_DMA_RING_THRESLD0_SET1_VAL,
1400 		  pdma->csr_ring + XGENE_DMA_RING_THRESLD0_SET1);
1401 	iowrite32(XGENE_DMA_RING_THRESLD1_SET1_VAL,
1402 		  pdma->csr_ring + XGENE_DMA_RING_THRESLD1_SET1);
1403 	iowrite32(XGENE_DMA_RING_HYSTERESIS_VAL,
1404 		  pdma->csr_ring + XGENE_DMA_RING_HYSTERESIS);
1405 
1406 	/* Enable QPcore and assign error queue */
1407 	iowrite32(XGENE_DMA_RING_ENABLE,
1408 		  pdma->csr_ring + XGENE_DMA_RING_CONFIG);
1409 
1410 	return 0;
1411 }
1412 
1413 static int xgene_dma_init_mem(struct xgene_dma *pdma)
1414 {
1415 	int ret;
1416 
1417 	ret = xgene_dma_init_ring_mngr(pdma);
1418 	if (ret)
1419 		return ret;
1420 
1421 	/* Bring up memory */
1422 	iowrite32(0x0, pdma->csr_dma + XGENE_DMA_MEM_RAM_SHUTDOWN);
1423 
1424 	/* Force a barrier */
1425 	ioread32(pdma->csr_dma + XGENE_DMA_MEM_RAM_SHUTDOWN);
1426 
1427 	/* reset may take up to 1ms */
1428 	usleep_range(1000, 1100);
1429 
1430 	if (ioread32(pdma->csr_dma + XGENE_DMA_BLK_MEM_RDY)
1431 		!= XGENE_DMA_BLK_MEM_RDY_VAL) {
1432 		dev_err(pdma->dev,
1433 			"Failed to release DMA memory from shutdown\n");
1434 		return -ENODEV;
1435 	}
1436 
1437 	return 0;
1438 }
1439 
1440 static int xgene_dma_request_irqs(struct xgene_dma *pdma)
1441 {
1442 	struct xgene_dma_chan *chan;
1443 	int ret, i, j;
1444 
1445 	/* Register DMA error irq */
1446 	ret = devm_request_irq(pdma->dev, pdma->err_irq, xgene_dma_err_isr,
1447 			       0, "dma_error", pdma);
1448 	if (ret) {
1449 		dev_err(pdma->dev,
1450 			"Failed to register error IRQ %d\n", pdma->err_irq);
1451 		return ret;
1452 	}
1453 
1454 	/* Register DMA channel rx irq */
1455 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1456 		chan = &pdma->chan[i];
1457 		irq_set_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1458 		ret = devm_request_irq(chan->dev, chan->rx_irq,
1459 				       xgene_dma_chan_ring_isr,
1460 				       0, chan->name, chan);
1461 		if (ret) {
1462 			chan_err(chan, "Failed to register Rx IRQ %d\n",
1463 				 chan->rx_irq);
1464 			devm_free_irq(pdma->dev, pdma->err_irq, pdma);
1465 
1466 			for (j = 0; j < i; j++) {
1467 				chan = &pdma->chan[i];
1468 				irq_clear_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1469 				devm_free_irq(chan->dev, chan->rx_irq, chan);
1470 			}
1471 
1472 			return ret;
1473 		}
1474 	}
1475 
1476 	return 0;
1477 }
1478 
1479 static void xgene_dma_free_irqs(struct xgene_dma *pdma)
1480 {
1481 	struct xgene_dma_chan *chan;
1482 	int i;
1483 
1484 	/* Free DMA device error irq */
1485 	devm_free_irq(pdma->dev, pdma->err_irq, pdma);
1486 
1487 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1488 		chan = &pdma->chan[i];
1489 		irq_clear_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1490 		devm_free_irq(chan->dev, chan->rx_irq, chan);
1491 	}
1492 }
1493 
1494 static void xgene_dma_set_caps(struct xgene_dma_chan *chan,
1495 			       struct dma_device *dma_dev)
1496 {
1497 	/* Initialize DMA device capability mask */
1498 	dma_cap_zero(dma_dev->cap_mask);
1499 
1500 	/* Set DMA device capability */
1501 
1502 	/* Basically here, the X-Gene SoC DMA engine channel 0 supports XOR
1503 	 * and channel 1 supports XOR, PQ both. First thing here is we have
1504 	 * mechanism in hw to enable/disable PQ/XOR supports on channel 1,
1505 	 * we can make sure this by reading SoC Efuse register.
1506 	 * Second thing, we have hw errata that if we run channel 0 and
1507 	 * channel 1 simultaneously with executing XOR and PQ request,
1508 	 * suddenly DMA engine hangs, So here we enable XOR on channel 0 only
1509 	 * if XOR and PQ supports on channel 1 is disabled.
1510 	 */
1511 	if ((chan->id == XGENE_DMA_PQ_CHANNEL) &&
1512 	    is_pq_enabled(chan->pdma)) {
1513 		dma_cap_set(DMA_PQ, dma_dev->cap_mask);
1514 		dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1515 	} else if ((chan->id == XGENE_DMA_XOR_CHANNEL) &&
1516 		   !is_pq_enabled(chan->pdma)) {
1517 		dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1518 	}
1519 
1520 	/* Set base and prep routines */
1521 	dma_dev->dev = chan->dev;
1522 	dma_dev->device_alloc_chan_resources = xgene_dma_alloc_chan_resources;
1523 	dma_dev->device_free_chan_resources = xgene_dma_free_chan_resources;
1524 	dma_dev->device_issue_pending = xgene_dma_issue_pending;
1525 	dma_dev->device_tx_status = xgene_dma_tx_status;
1526 
1527 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1528 		dma_dev->device_prep_dma_xor = xgene_dma_prep_xor;
1529 		dma_dev->max_xor = XGENE_DMA_MAX_XOR_SRC;
1530 		dma_dev->xor_align = DMAENGINE_ALIGN_64_BYTES;
1531 	}
1532 
1533 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
1534 		dma_dev->device_prep_dma_pq = xgene_dma_prep_pq;
1535 		dma_dev->max_pq = XGENE_DMA_MAX_XOR_SRC;
1536 		dma_dev->pq_align = DMAENGINE_ALIGN_64_BYTES;
1537 	}
1538 }
1539 
1540 static int xgene_dma_async_register(struct xgene_dma *pdma, int id)
1541 {
1542 	struct xgene_dma_chan *chan = &pdma->chan[id];
1543 	struct dma_device *dma_dev = &pdma->dma_dev[id];
1544 	int ret;
1545 
1546 	chan->dma_chan.device = dma_dev;
1547 
1548 	spin_lock_init(&chan->lock);
1549 	INIT_LIST_HEAD(&chan->ld_pending);
1550 	INIT_LIST_HEAD(&chan->ld_running);
1551 	INIT_LIST_HEAD(&chan->ld_completed);
1552 	tasklet_init(&chan->tasklet, xgene_dma_tasklet_cb,
1553 		     (unsigned long)chan);
1554 
1555 	chan->pending = 0;
1556 	chan->desc_pool = NULL;
1557 	dma_cookie_init(&chan->dma_chan);
1558 
1559 	/* Setup dma device capabilities and prep routines */
1560 	xgene_dma_set_caps(chan, dma_dev);
1561 
1562 	/* Initialize DMA device list head */
1563 	INIT_LIST_HEAD(&dma_dev->channels);
1564 	list_add_tail(&chan->dma_chan.device_node, &dma_dev->channels);
1565 
1566 	/* Register with Linux async DMA framework*/
1567 	ret = dma_async_device_register(dma_dev);
1568 	if (ret) {
1569 		chan_err(chan, "Failed to register async device %d", ret);
1570 		tasklet_kill(&chan->tasklet);
1571 
1572 		return ret;
1573 	}
1574 
1575 	/* DMA capability info */
1576 	dev_info(pdma->dev,
1577 		 "%s: CAPABILITY ( %s%s)\n", dma_chan_name(&chan->dma_chan),
1578 		 dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "XOR " : "",
1579 		 dma_has_cap(DMA_PQ, dma_dev->cap_mask) ? "PQ " : "");
1580 
1581 	return 0;
1582 }
1583 
1584 static int xgene_dma_init_async(struct xgene_dma *pdma)
1585 {
1586 	int ret, i, j;
1587 
1588 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL ; i++) {
1589 		ret = xgene_dma_async_register(pdma, i);
1590 		if (ret) {
1591 			for (j = 0; j < i; j++) {
1592 				dma_async_device_unregister(&pdma->dma_dev[j]);
1593 				tasklet_kill(&pdma->chan[j].tasklet);
1594 			}
1595 
1596 			return ret;
1597 		}
1598 	}
1599 
1600 	return ret;
1601 }
1602 
1603 static void xgene_dma_async_unregister(struct xgene_dma *pdma)
1604 {
1605 	int i;
1606 
1607 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++)
1608 		dma_async_device_unregister(&pdma->dma_dev[i]);
1609 }
1610 
1611 static void xgene_dma_init_channels(struct xgene_dma *pdma)
1612 {
1613 	struct xgene_dma_chan *chan;
1614 	int i;
1615 
1616 	pdma->ring_num = XGENE_DMA_RING_NUM;
1617 
1618 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1619 		chan = &pdma->chan[i];
1620 		chan->dev = pdma->dev;
1621 		chan->pdma = pdma;
1622 		chan->id = i;
1623 		snprintf(chan->name, sizeof(chan->name), "dmachan%d", chan->id);
1624 	}
1625 }
1626 
1627 static int xgene_dma_get_resources(struct platform_device *pdev,
1628 				   struct xgene_dma *pdma)
1629 {
1630 	struct resource *res;
1631 	int irq, i;
1632 
1633 	/* Get DMA csr region */
1634 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1635 	if (!res) {
1636 		dev_err(&pdev->dev, "Failed to get csr region\n");
1637 		return -ENXIO;
1638 	}
1639 
1640 	pdma->csr_dma = devm_ioremap(&pdev->dev, res->start,
1641 				     resource_size(res));
1642 	if (!pdma->csr_dma) {
1643 		dev_err(&pdev->dev, "Failed to ioremap csr region");
1644 		return -ENOMEM;
1645 	}
1646 
1647 	/* Get DMA ring csr region */
1648 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1649 	if (!res) {
1650 		dev_err(&pdev->dev, "Failed to get ring csr region\n");
1651 		return -ENXIO;
1652 	}
1653 
1654 	pdma->csr_ring =  devm_ioremap(&pdev->dev, res->start,
1655 				       resource_size(res));
1656 	if (!pdma->csr_ring) {
1657 		dev_err(&pdev->dev, "Failed to ioremap ring csr region");
1658 		return -ENOMEM;
1659 	}
1660 
1661 	/* Get DMA ring cmd csr region */
1662 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
1663 	if (!res) {
1664 		dev_err(&pdev->dev, "Failed to get ring cmd csr region\n");
1665 		return -ENXIO;
1666 	}
1667 
1668 	pdma->csr_ring_cmd = devm_ioremap(&pdev->dev, res->start,
1669 					  resource_size(res));
1670 	if (!pdma->csr_ring_cmd) {
1671 		dev_err(&pdev->dev, "Failed to ioremap ring cmd csr region");
1672 		return -ENOMEM;
1673 	}
1674 
1675 	pdma->csr_ring_cmd += XGENE_DMA_RING_CMD_SM_OFFSET;
1676 
1677 	/* Get efuse csr region */
1678 	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
1679 	if (!res) {
1680 		dev_err(&pdev->dev, "Failed to get efuse csr region\n");
1681 		return -ENXIO;
1682 	}
1683 
1684 	pdma->csr_efuse = devm_ioremap(&pdev->dev, res->start,
1685 				       resource_size(res));
1686 	if (!pdma->csr_efuse) {
1687 		dev_err(&pdev->dev, "Failed to ioremap efuse csr region");
1688 		return -ENOMEM;
1689 	}
1690 
1691 	/* Get DMA error interrupt */
1692 	irq = platform_get_irq(pdev, 0);
1693 	if (irq <= 0) {
1694 		dev_err(&pdev->dev, "Failed to get Error IRQ\n");
1695 		return -ENXIO;
1696 	}
1697 
1698 	pdma->err_irq = irq;
1699 
1700 	/* Get DMA Rx ring descriptor interrupts for all DMA channels */
1701 	for (i = 1; i <= XGENE_DMA_MAX_CHANNEL; i++) {
1702 		irq = platform_get_irq(pdev, i);
1703 		if (irq <= 0) {
1704 			dev_err(&pdev->dev, "Failed to get Rx IRQ\n");
1705 			return -ENXIO;
1706 		}
1707 
1708 		pdma->chan[i - 1].rx_irq = irq;
1709 	}
1710 
1711 	return 0;
1712 }
1713 
1714 static int xgene_dma_probe(struct platform_device *pdev)
1715 {
1716 	struct xgene_dma *pdma;
1717 	int ret, i;
1718 
1719 	pdma = devm_kzalloc(&pdev->dev, sizeof(*pdma), GFP_KERNEL);
1720 	if (!pdma)
1721 		return -ENOMEM;
1722 
1723 	pdma->dev = &pdev->dev;
1724 	platform_set_drvdata(pdev, pdma);
1725 
1726 	ret = xgene_dma_get_resources(pdev, pdma);
1727 	if (ret)
1728 		return ret;
1729 
1730 	pdma->clk = devm_clk_get(&pdev->dev, NULL);
1731 	if (IS_ERR(pdma->clk) && !ACPI_COMPANION(&pdev->dev)) {
1732 		dev_err(&pdev->dev, "Failed to get clk\n");
1733 		return PTR_ERR(pdma->clk);
1734 	}
1735 
1736 	/* Enable clk before accessing registers */
1737 	if (!IS_ERR(pdma->clk)) {
1738 		ret = clk_prepare_enable(pdma->clk);
1739 		if (ret) {
1740 			dev_err(&pdev->dev, "Failed to enable clk %d\n", ret);
1741 			return ret;
1742 		}
1743 	}
1744 
1745 	/* Remove DMA RAM out of shutdown */
1746 	ret = xgene_dma_init_mem(pdma);
1747 	if (ret)
1748 		goto err_clk_enable;
1749 
1750 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(42));
1751 	if (ret) {
1752 		dev_err(&pdev->dev, "No usable DMA configuration\n");
1753 		goto err_dma_mask;
1754 	}
1755 
1756 	/* Initialize DMA channels software state */
1757 	xgene_dma_init_channels(pdma);
1758 
1759 	/* Configue DMA rings */
1760 	ret = xgene_dma_init_rings(pdma);
1761 	if (ret)
1762 		goto err_clk_enable;
1763 
1764 	ret = xgene_dma_request_irqs(pdma);
1765 	if (ret)
1766 		goto err_request_irq;
1767 
1768 	/* Configure and enable DMA engine */
1769 	xgene_dma_init_hw(pdma);
1770 
1771 	/* Register DMA device with linux async framework */
1772 	ret = xgene_dma_init_async(pdma);
1773 	if (ret)
1774 		goto err_async_init;
1775 
1776 	return 0;
1777 
1778 err_async_init:
1779 	xgene_dma_free_irqs(pdma);
1780 
1781 err_request_irq:
1782 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++)
1783 		xgene_dma_delete_chan_rings(&pdma->chan[i]);
1784 
1785 err_dma_mask:
1786 err_clk_enable:
1787 	if (!IS_ERR(pdma->clk))
1788 		clk_disable_unprepare(pdma->clk);
1789 
1790 	return ret;
1791 }
1792 
1793 static int xgene_dma_remove(struct platform_device *pdev)
1794 {
1795 	struct xgene_dma *pdma = platform_get_drvdata(pdev);
1796 	struct xgene_dma_chan *chan;
1797 	int i;
1798 
1799 	xgene_dma_async_unregister(pdma);
1800 
1801 	/* Mask interrupts and disable DMA engine */
1802 	xgene_dma_mask_interrupts(pdma);
1803 	xgene_dma_disable(pdma);
1804 	xgene_dma_free_irqs(pdma);
1805 
1806 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1807 		chan = &pdma->chan[i];
1808 		tasklet_kill(&chan->tasklet);
1809 		xgene_dma_delete_chan_rings(chan);
1810 	}
1811 
1812 	if (!IS_ERR(pdma->clk))
1813 		clk_disable_unprepare(pdma->clk);
1814 
1815 	return 0;
1816 }
1817 
1818 #ifdef CONFIG_ACPI
1819 static const struct acpi_device_id xgene_dma_acpi_match_ptr[] = {
1820 	{"APMC0D43", 0},
1821 	{},
1822 };
1823 MODULE_DEVICE_TABLE(acpi, xgene_dma_acpi_match_ptr);
1824 #endif
1825 
1826 static const struct of_device_id xgene_dma_of_match_ptr[] = {
1827 	{.compatible = "apm,xgene-storm-dma",},
1828 	{},
1829 };
1830 MODULE_DEVICE_TABLE(of, xgene_dma_of_match_ptr);
1831 
1832 static struct platform_driver xgene_dma_driver = {
1833 	.probe = xgene_dma_probe,
1834 	.remove = xgene_dma_remove,
1835 	.driver = {
1836 		.name = "X-Gene-DMA",
1837 		.of_match_table = xgene_dma_of_match_ptr,
1838 		.acpi_match_table = ACPI_PTR(xgene_dma_acpi_match_ptr),
1839 	},
1840 };
1841 
1842 module_platform_driver(xgene_dma_driver);
1843 
1844 MODULE_DESCRIPTION("APM X-Gene SoC DMA driver");
1845 MODULE_AUTHOR("Rameshwar Prasad Sahu <rsahu@apm.com>");
1846 MODULE_AUTHOR("Loc Ho <lho@apm.com>");
1847 MODULE_LICENSE("GPL");
1848 MODULE_VERSION("1.0");
1849