xref: /openbmc/linux/drivers/dma/xgene-dma.c (revision a06c488d)
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 void xgene_dma_invalidate_buffer(__le64 *ext8)
395 {
396 	*ext8 |= cpu_to_le64(XGENE_DMA_INVALID_LEN_CODE);
397 }
398 
399 static __le64 *xgene_dma_lookup_ext8(struct xgene_dma_desc_hw *desc, int idx)
400 {
401 	switch (idx) {
402 	case 0:
403 		return &desc->m1;
404 	case 1:
405 		return &desc->m0;
406 	case 2:
407 		return &desc->m3;
408 	case 3:
409 		return &desc->m2;
410 	default:
411 		pr_err("Invalid dma descriptor index\n");
412 	}
413 
414 	return NULL;
415 }
416 
417 static void xgene_dma_init_desc(struct xgene_dma_desc_hw *desc,
418 				u16 dst_ring_num)
419 {
420 	desc->m0 |= cpu_to_le64(XGENE_DMA_DESC_IN_BIT);
421 	desc->m0 |= cpu_to_le64((u64)XGENE_DMA_RING_OWNER_DMA <<
422 				XGENE_DMA_DESC_RTYPE_POS);
423 	desc->m1 |= cpu_to_le64(XGENE_DMA_DESC_C_BIT);
424 	desc->m3 |= cpu_to_le64((u64)dst_ring_num <<
425 				XGENE_DMA_DESC_HOENQ_NUM_POS);
426 }
427 
428 static void xgene_dma_prep_cpy_desc(struct xgene_dma_chan *chan,
429 				    struct xgene_dma_desc_sw *desc_sw,
430 				    dma_addr_t dst, dma_addr_t src,
431 				    size_t len)
432 {
433 	struct xgene_dma_desc_hw *desc1, *desc2;
434 	int i;
435 
436 	/* Get 1st descriptor */
437 	desc1 = &desc_sw->desc1;
438 	xgene_dma_init_desc(desc1, chan->tx_ring.dst_ring_num);
439 
440 	/* Set destination address */
441 	desc1->m2 |= cpu_to_le64(XGENE_DMA_DESC_DR_BIT);
442 	desc1->m3 |= cpu_to_le64(dst);
443 
444 	/* Set 1st source address */
445 	xgene_dma_set_src_buffer(&desc1->m1, &len, &src);
446 
447 	if (!len)
448 		return;
449 
450 	/*
451 	 * We need to split this source buffer,
452 	 * and need to use 2nd descriptor
453 	 */
454 	desc2 = &desc_sw->desc2;
455 	desc1->m0 |= cpu_to_le64(XGENE_DMA_DESC_NV_BIT);
456 
457 	/* Set 2nd to 5th source address */
458 	for (i = 0; i < 4 && len; i++)
459 		xgene_dma_set_src_buffer(xgene_dma_lookup_ext8(desc2, i),
460 					 &len, &src);
461 
462 	/* Invalidate unused source address field */
463 	for (; i < 4; i++)
464 		xgene_dma_invalidate_buffer(xgene_dma_lookup_ext8(desc2, i));
465 
466 	/* Updated flag that we have prepared 64B descriptor */
467 	desc_sw->flags |= XGENE_DMA_FLAG_64B_DESC;
468 }
469 
470 static void xgene_dma_prep_xor_desc(struct xgene_dma_chan *chan,
471 				    struct xgene_dma_desc_sw *desc_sw,
472 				    dma_addr_t *dst, dma_addr_t *src,
473 				    u32 src_cnt, size_t *nbytes,
474 				    const u8 *scf)
475 {
476 	struct xgene_dma_desc_hw *desc1, *desc2;
477 	size_t len = *nbytes;
478 	int i;
479 
480 	desc1 = &desc_sw->desc1;
481 	desc2 = &desc_sw->desc2;
482 
483 	/* Initialize DMA descriptor */
484 	xgene_dma_init_desc(desc1, chan->tx_ring.dst_ring_num);
485 
486 	/* Set destination address */
487 	desc1->m2 |= cpu_to_le64(XGENE_DMA_DESC_DR_BIT);
488 	desc1->m3 |= cpu_to_le64(*dst);
489 
490 	/* We have multiple source addresses, so need to set NV bit*/
491 	desc1->m0 |= cpu_to_le64(XGENE_DMA_DESC_NV_BIT);
492 
493 	/* Set flyby opcode */
494 	desc1->m2 |= cpu_to_le64(xgene_dma_encode_xor_flyby(src_cnt));
495 
496 	/* Set 1st to 5th source addresses */
497 	for (i = 0; i < src_cnt; i++) {
498 		len = *nbytes;
499 		xgene_dma_set_src_buffer((i == 0) ? &desc1->m1 :
500 					 xgene_dma_lookup_ext8(desc2, i - 1),
501 					 &len, &src[i]);
502 		desc1->m2 |= cpu_to_le64((scf[i] << ((i + 1) * 8)));
503 	}
504 
505 	/* Update meta data */
506 	*nbytes = len;
507 	*dst += XGENE_DMA_MAX_BYTE_CNT;
508 
509 	/* We need always 64B descriptor to perform xor or pq operations */
510 	desc_sw->flags |= XGENE_DMA_FLAG_64B_DESC;
511 }
512 
513 static dma_cookie_t xgene_dma_tx_submit(struct dma_async_tx_descriptor *tx)
514 {
515 	struct xgene_dma_desc_sw *desc;
516 	struct xgene_dma_chan *chan;
517 	dma_cookie_t cookie;
518 
519 	if (unlikely(!tx))
520 		return -EINVAL;
521 
522 	chan = to_dma_chan(tx->chan);
523 	desc = to_dma_desc_sw(tx);
524 
525 	spin_lock_bh(&chan->lock);
526 
527 	cookie = dma_cookie_assign(tx);
528 
529 	/* Add this transaction list onto the tail of the pending queue */
530 	list_splice_tail_init(&desc->tx_list, &chan->ld_pending);
531 
532 	spin_unlock_bh(&chan->lock);
533 
534 	return cookie;
535 }
536 
537 static void xgene_dma_clean_descriptor(struct xgene_dma_chan *chan,
538 				       struct xgene_dma_desc_sw *desc)
539 {
540 	list_del(&desc->node);
541 	chan_dbg(chan, "LD %p free\n", desc);
542 	dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
543 }
544 
545 static struct xgene_dma_desc_sw *xgene_dma_alloc_descriptor(
546 				 struct xgene_dma_chan *chan)
547 {
548 	struct xgene_dma_desc_sw *desc;
549 	dma_addr_t phys;
550 
551 	desc = dma_pool_zalloc(chan->desc_pool, GFP_NOWAIT, &phys);
552 	if (!desc) {
553 		chan_err(chan, "Failed to allocate LDs\n");
554 		return NULL;
555 	}
556 
557 	INIT_LIST_HEAD(&desc->tx_list);
558 	desc->tx.phys = phys;
559 	desc->tx.tx_submit = xgene_dma_tx_submit;
560 	dma_async_tx_descriptor_init(&desc->tx, &chan->dma_chan);
561 
562 	chan_dbg(chan, "LD %p allocated\n", desc);
563 
564 	return desc;
565 }
566 
567 /**
568  * xgene_dma_clean_completed_descriptor - free all descriptors which
569  * has been completed and acked
570  * @chan: X-Gene DMA channel
571  *
572  * This function is used on all completed and acked descriptors.
573  */
574 static void xgene_dma_clean_completed_descriptor(struct xgene_dma_chan *chan)
575 {
576 	struct xgene_dma_desc_sw *desc, *_desc;
577 
578 	/* Run the callback for each descriptor, in order */
579 	list_for_each_entry_safe(desc, _desc, &chan->ld_completed, node) {
580 		if (async_tx_test_ack(&desc->tx))
581 			xgene_dma_clean_descriptor(chan, desc);
582 	}
583 }
584 
585 /**
586  * xgene_dma_run_tx_complete_actions - cleanup a single link descriptor
587  * @chan: X-Gene DMA channel
588  * @desc: descriptor to cleanup and free
589  *
590  * This function is used on a descriptor which has been executed by the DMA
591  * controller. It will run any callbacks, submit any dependencies.
592  */
593 static void xgene_dma_run_tx_complete_actions(struct xgene_dma_chan *chan,
594 					      struct xgene_dma_desc_sw *desc)
595 {
596 	struct dma_async_tx_descriptor *tx = &desc->tx;
597 
598 	/*
599 	 * If this is not the last transaction in the group,
600 	 * then no need to complete cookie and run any callback as
601 	 * this is not the tx_descriptor which had been sent to caller
602 	 * of this DMA request
603 	 */
604 
605 	if (tx->cookie == 0)
606 		return;
607 
608 	dma_cookie_complete(tx);
609 
610 	/* Run the link descriptor callback function */
611 	if (tx->callback)
612 		tx->callback(tx->callback_param);
613 
614 	dma_descriptor_unmap(tx);
615 
616 	/* Run any dependencies */
617 	dma_run_dependencies(tx);
618 }
619 
620 /**
621  * xgene_dma_clean_running_descriptor - move the completed descriptor from
622  * ld_running to ld_completed
623  * @chan: X-Gene DMA channel
624  * @desc: the descriptor which is completed
625  *
626  * Free the descriptor directly if acked by async_tx api,
627  * else move it to queue ld_completed.
628  */
629 static void xgene_dma_clean_running_descriptor(struct xgene_dma_chan *chan,
630 					       struct xgene_dma_desc_sw *desc)
631 {
632 	/* Remove from the list of running transactions */
633 	list_del(&desc->node);
634 
635 	/*
636 	 * the client is allowed to attach dependent operations
637 	 * until 'ack' is set
638 	 */
639 	if (!async_tx_test_ack(&desc->tx)) {
640 		/*
641 		 * Move this descriptor to the list of descriptors which is
642 		 * completed, but still awaiting the 'ack' bit to be set.
643 		 */
644 		list_add_tail(&desc->node, &chan->ld_completed);
645 		return;
646 	}
647 
648 	chan_dbg(chan, "LD %p free\n", desc);
649 	dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
650 }
651 
652 static void xgene_chan_xfer_request(struct xgene_dma_chan *chan,
653 				    struct xgene_dma_desc_sw *desc_sw)
654 {
655 	struct xgene_dma_ring *ring = &chan->tx_ring;
656 	struct xgene_dma_desc_hw *desc_hw;
657 
658 	/* Get hw descriptor from DMA tx ring */
659 	desc_hw = &ring->desc_hw[ring->head];
660 
661 	/*
662 	 * Increment the head count to point next
663 	 * descriptor for next time
664 	 */
665 	if (++ring->head == ring->slots)
666 		ring->head = 0;
667 
668 	/* Copy prepared sw descriptor data to hw descriptor */
669 	memcpy(desc_hw, &desc_sw->desc1, sizeof(*desc_hw));
670 
671 	/*
672 	 * Check if we have prepared 64B descriptor,
673 	 * in this case we need one more hw descriptor
674 	 */
675 	if (desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) {
676 		desc_hw = &ring->desc_hw[ring->head];
677 
678 		if (++ring->head == ring->slots)
679 			ring->head = 0;
680 
681 		memcpy(desc_hw, &desc_sw->desc2, sizeof(*desc_hw));
682 	}
683 
684 	/* Increment the pending transaction count */
685 	chan->pending += ((desc_sw->flags &
686 			  XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
687 
688 	/* Notify the hw that we have descriptor ready for execution */
689 	iowrite32((desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) ?
690 		  2 : 1, ring->cmd);
691 }
692 
693 /**
694  * xgene_chan_xfer_ld_pending - push any pending transactions to hw
695  * @chan : X-Gene DMA channel
696  *
697  * LOCKING: must hold chan->lock
698  */
699 static void xgene_chan_xfer_ld_pending(struct xgene_dma_chan *chan)
700 {
701 	struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
702 
703 	/*
704 	 * If the list of pending descriptors is empty, then we
705 	 * don't need to do any work at all
706 	 */
707 	if (list_empty(&chan->ld_pending)) {
708 		chan_dbg(chan, "No pending LDs\n");
709 		return;
710 	}
711 
712 	/*
713 	 * Move elements from the queue of pending transactions onto the list
714 	 * of running transactions and push it to hw for further executions
715 	 */
716 	list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_pending, node) {
717 		/*
718 		 * Check if have pushed max number of transactions to hw
719 		 * as capable, so let's stop here and will push remaining
720 		 * elements from pening ld queue after completing some
721 		 * descriptors that we have already pushed
722 		 */
723 		if (chan->pending >= chan->max_outstanding)
724 			return;
725 
726 		xgene_chan_xfer_request(chan, desc_sw);
727 
728 		/*
729 		 * Delete this element from ld pending queue and append it to
730 		 * ld running queue
731 		 */
732 		list_move_tail(&desc_sw->node, &chan->ld_running);
733 	}
734 }
735 
736 /**
737  * xgene_dma_cleanup_descriptors - cleanup link descriptors which are completed
738  * and move them to ld_completed to free until flag 'ack' is set
739  * @chan: X-Gene DMA channel
740  *
741  * This function is used on descriptors which have been executed by the DMA
742  * controller. It will run any callbacks, submit any dependencies, then
743  * free these descriptors if flag 'ack' is set.
744  */
745 static void xgene_dma_cleanup_descriptors(struct xgene_dma_chan *chan)
746 {
747 	struct xgene_dma_ring *ring = &chan->rx_ring;
748 	struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
749 	struct xgene_dma_desc_hw *desc_hw;
750 	struct list_head ld_completed;
751 	u8 status;
752 
753 	INIT_LIST_HEAD(&ld_completed);
754 
755 	spin_lock_bh(&chan->lock);
756 
757 	/* Clean already completed and acked descriptors */
758 	xgene_dma_clean_completed_descriptor(chan);
759 
760 	/* Move all completed descriptors to ld completed queue, in order */
761 	list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_running, node) {
762 		/* Get subsequent hw descriptor from DMA rx ring */
763 		desc_hw = &ring->desc_hw[ring->head];
764 
765 		/* Check if this descriptor has been completed */
766 		if (unlikely(le64_to_cpu(desc_hw->m0) ==
767 			     XGENE_DMA_DESC_EMPTY_SIGNATURE))
768 			break;
769 
770 		if (++ring->head == ring->slots)
771 			ring->head = 0;
772 
773 		/* Check if we have any error with DMA transactions */
774 		status = XGENE_DMA_DESC_STATUS(
775 				XGENE_DMA_DESC_ELERR_RD(le64_to_cpu(
776 							desc_hw->m0)),
777 				XGENE_DMA_DESC_LERR_RD(le64_to_cpu(
778 						       desc_hw->m0)));
779 		if (status) {
780 			/* Print the DMA error type */
781 			chan_err(chan, "%s\n", xgene_dma_desc_err[status]);
782 
783 			/*
784 			 * We have DMA transactions error here. Dump DMA Tx
785 			 * and Rx descriptors for this request */
786 			XGENE_DMA_DESC_DUMP(&desc_sw->desc1,
787 					    "X-Gene DMA TX DESC1: ");
788 
789 			if (desc_sw->flags & XGENE_DMA_FLAG_64B_DESC)
790 				XGENE_DMA_DESC_DUMP(&desc_sw->desc2,
791 						    "X-Gene DMA TX DESC2: ");
792 
793 			XGENE_DMA_DESC_DUMP(desc_hw,
794 					    "X-Gene DMA RX ERR DESC: ");
795 		}
796 
797 		/* Notify the hw about this completed descriptor */
798 		iowrite32(-1, ring->cmd);
799 
800 		/* Mark this hw descriptor as processed */
801 		desc_hw->m0 = cpu_to_le64(XGENE_DMA_DESC_EMPTY_SIGNATURE);
802 
803 		/*
804 		 * Decrement the pending transaction count
805 		 * as we have processed one
806 		 */
807 		chan->pending -= ((desc_sw->flags &
808 				  XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
809 
810 		/*
811 		 * Delete this node from ld running queue and append it to
812 		 * ld completed queue for further processing
813 		 */
814 		list_move_tail(&desc_sw->node, &ld_completed);
815 	}
816 
817 	/*
818 	 * Start any pending transactions automatically
819 	 * In the ideal case, we keep the DMA controller busy while we go
820 	 * ahead and free the descriptors below.
821 	 */
822 	xgene_chan_xfer_ld_pending(chan);
823 
824 	spin_unlock_bh(&chan->lock);
825 
826 	/* Run the callback for each descriptor, in order */
827 	list_for_each_entry_safe(desc_sw, _desc_sw, &ld_completed, node) {
828 		xgene_dma_run_tx_complete_actions(chan, desc_sw);
829 		xgene_dma_clean_running_descriptor(chan, desc_sw);
830 	}
831 }
832 
833 static int xgene_dma_alloc_chan_resources(struct dma_chan *dchan)
834 {
835 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
836 
837 	/* Has this channel already been allocated? */
838 	if (chan->desc_pool)
839 		return 1;
840 
841 	chan->desc_pool = dma_pool_create(chan->name, chan->dev,
842 					  sizeof(struct xgene_dma_desc_sw),
843 					  0, 0);
844 	if (!chan->desc_pool) {
845 		chan_err(chan, "Failed to allocate descriptor pool\n");
846 		return -ENOMEM;
847 	}
848 
849 	chan_dbg(chan, "Allocate descripto pool\n");
850 
851 	return 1;
852 }
853 
854 /**
855  * xgene_dma_free_desc_list - Free all descriptors in a queue
856  * @chan: X-Gene DMA channel
857  * @list: the list to free
858  *
859  * LOCKING: must hold chan->lock
860  */
861 static void xgene_dma_free_desc_list(struct xgene_dma_chan *chan,
862 				     struct list_head *list)
863 {
864 	struct xgene_dma_desc_sw *desc, *_desc;
865 
866 	list_for_each_entry_safe(desc, _desc, list, node)
867 		xgene_dma_clean_descriptor(chan, desc);
868 }
869 
870 static void xgene_dma_free_chan_resources(struct dma_chan *dchan)
871 {
872 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
873 
874 	chan_dbg(chan, "Free all resources\n");
875 
876 	if (!chan->desc_pool)
877 		return;
878 
879 	/* Process all running descriptor */
880 	xgene_dma_cleanup_descriptors(chan);
881 
882 	spin_lock_bh(&chan->lock);
883 
884 	/* Clean all link descriptor queues */
885 	xgene_dma_free_desc_list(chan, &chan->ld_pending);
886 	xgene_dma_free_desc_list(chan, &chan->ld_running);
887 	xgene_dma_free_desc_list(chan, &chan->ld_completed);
888 
889 	spin_unlock_bh(&chan->lock);
890 
891 	/* Delete this channel DMA pool */
892 	dma_pool_destroy(chan->desc_pool);
893 	chan->desc_pool = NULL;
894 }
895 
896 static struct dma_async_tx_descriptor *xgene_dma_prep_sg(
897 	struct dma_chan *dchan, struct scatterlist *dst_sg,
898 	u32 dst_nents, struct scatterlist *src_sg,
899 	u32 src_nents, unsigned long flags)
900 {
901 	struct xgene_dma_desc_sw *first = NULL, *new = NULL;
902 	struct xgene_dma_chan *chan;
903 	size_t dst_avail, src_avail;
904 	dma_addr_t dst, src;
905 	size_t len;
906 
907 	if (unlikely(!dchan))
908 		return NULL;
909 
910 	if (unlikely(!dst_nents || !src_nents))
911 		return NULL;
912 
913 	if (unlikely(!dst_sg || !src_sg))
914 		return NULL;
915 
916 	chan = to_dma_chan(dchan);
917 
918 	/* Get prepared for the loop */
919 	dst_avail = sg_dma_len(dst_sg);
920 	src_avail = sg_dma_len(src_sg);
921 	dst_nents--;
922 	src_nents--;
923 
924 	/* Run until we are out of scatterlist entries */
925 	while (true) {
926 		/* Create the largest transaction possible */
927 		len = min_t(size_t, src_avail, dst_avail);
928 		len = min_t(size_t, len, XGENE_DMA_MAX_64B_DESC_BYTE_CNT);
929 		if (len == 0)
930 			goto fetch;
931 
932 		dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) - dst_avail;
933 		src = sg_dma_address(src_sg) + sg_dma_len(src_sg) - src_avail;
934 
935 		/* Allocate the link descriptor from DMA pool */
936 		new = xgene_dma_alloc_descriptor(chan);
937 		if (!new)
938 			goto fail;
939 
940 		/* Prepare DMA descriptor */
941 		xgene_dma_prep_cpy_desc(chan, new, dst, src, len);
942 
943 		if (!first)
944 			first = new;
945 
946 		new->tx.cookie = 0;
947 		async_tx_ack(&new->tx);
948 
949 		/* update metadata */
950 		dst_avail -= len;
951 		src_avail -= len;
952 
953 		/* Insert the link descriptor to the LD ring */
954 		list_add_tail(&new->node, &first->tx_list);
955 
956 fetch:
957 		/* fetch the next dst scatterlist entry */
958 		if (dst_avail == 0) {
959 			/* no more entries: we're done */
960 			if (dst_nents == 0)
961 				break;
962 
963 			/* fetch the next entry: if there are no more: done */
964 			dst_sg = sg_next(dst_sg);
965 			if (!dst_sg)
966 				break;
967 
968 			dst_nents--;
969 			dst_avail = sg_dma_len(dst_sg);
970 		}
971 
972 		/* fetch the next src scatterlist entry */
973 		if (src_avail == 0) {
974 			/* no more entries: we're done */
975 			if (src_nents == 0)
976 				break;
977 
978 			/* fetch the next entry: if there are no more: done */
979 			src_sg = sg_next(src_sg);
980 			if (!src_sg)
981 				break;
982 
983 			src_nents--;
984 			src_avail = sg_dma_len(src_sg);
985 		}
986 	}
987 
988 	if (!new)
989 		return NULL;
990 
991 	new->tx.flags = flags; /* client is in control of this ack */
992 	new->tx.cookie = -EBUSY;
993 	list_splice(&first->tx_list, &new->tx_list);
994 
995 	return &new->tx;
996 fail:
997 	if (!first)
998 		return NULL;
999 
1000 	xgene_dma_free_desc_list(chan, &first->tx_list);
1001 	return NULL;
1002 }
1003 
1004 static struct dma_async_tx_descriptor *xgene_dma_prep_xor(
1005 	struct dma_chan *dchan, dma_addr_t dst,	dma_addr_t *src,
1006 	u32 src_cnt, size_t len, unsigned long flags)
1007 {
1008 	struct xgene_dma_desc_sw *first = NULL, *new;
1009 	struct xgene_dma_chan *chan;
1010 	static u8 multi[XGENE_DMA_MAX_XOR_SRC] = {
1011 				0x01, 0x01, 0x01, 0x01, 0x01};
1012 
1013 	if (unlikely(!dchan || !len))
1014 		return NULL;
1015 
1016 	chan = to_dma_chan(dchan);
1017 
1018 	do {
1019 		/* Allocate the link descriptor from DMA pool */
1020 		new = xgene_dma_alloc_descriptor(chan);
1021 		if (!new)
1022 			goto fail;
1023 
1024 		/* Prepare xor DMA descriptor */
1025 		xgene_dma_prep_xor_desc(chan, new, &dst, src,
1026 					src_cnt, &len, multi);
1027 
1028 		if (!first)
1029 			first = new;
1030 
1031 		new->tx.cookie = 0;
1032 		async_tx_ack(&new->tx);
1033 
1034 		/* Insert the link descriptor to the LD ring */
1035 		list_add_tail(&new->node, &first->tx_list);
1036 	} while (len);
1037 
1038 	new->tx.flags = flags; /* client is in control of this ack */
1039 	new->tx.cookie = -EBUSY;
1040 	list_splice(&first->tx_list, &new->tx_list);
1041 
1042 	return &new->tx;
1043 
1044 fail:
1045 	if (!first)
1046 		return NULL;
1047 
1048 	xgene_dma_free_desc_list(chan, &first->tx_list);
1049 	return NULL;
1050 }
1051 
1052 static struct dma_async_tx_descriptor *xgene_dma_prep_pq(
1053 	struct dma_chan *dchan, dma_addr_t *dst, dma_addr_t *src,
1054 	u32 src_cnt, const u8 *scf, size_t len, unsigned long flags)
1055 {
1056 	struct xgene_dma_desc_sw *first = NULL, *new;
1057 	struct xgene_dma_chan *chan;
1058 	size_t _len = len;
1059 	dma_addr_t _src[XGENE_DMA_MAX_XOR_SRC];
1060 	static u8 multi[XGENE_DMA_MAX_XOR_SRC] = {0x01, 0x01, 0x01, 0x01, 0x01};
1061 
1062 	if (unlikely(!dchan || !len))
1063 		return NULL;
1064 
1065 	chan = to_dma_chan(dchan);
1066 
1067 	/*
1068 	 * Save source addresses on local variable, may be we have to
1069 	 * prepare two descriptor to generate P and Q if both enabled
1070 	 * in the flags by client
1071 	 */
1072 	memcpy(_src, src, sizeof(*src) * src_cnt);
1073 
1074 	if (flags & DMA_PREP_PQ_DISABLE_P)
1075 		len = 0;
1076 
1077 	if (flags & DMA_PREP_PQ_DISABLE_Q)
1078 		_len = 0;
1079 
1080 	do {
1081 		/* Allocate the link descriptor from DMA pool */
1082 		new = xgene_dma_alloc_descriptor(chan);
1083 		if (!new)
1084 			goto fail;
1085 
1086 		if (!first)
1087 			first = new;
1088 
1089 		new->tx.cookie = 0;
1090 		async_tx_ack(&new->tx);
1091 
1092 		/* Insert the link descriptor to the LD ring */
1093 		list_add_tail(&new->node, &first->tx_list);
1094 
1095 		/*
1096 		 * Prepare DMA descriptor to generate P,
1097 		 * if DMA_PREP_PQ_DISABLE_P flag is not set
1098 		 */
1099 		if (len) {
1100 			xgene_dma_prep_xor_desc(chan, new, &dst[0], src,
1101 						src_cnt, &len, multi);
1102 			continue;
1103 		}
1104 
1105 		/*
1106 		 * Prepare DMA descriptor to generate Q,
1107 		 * if DMA_PREP_PQ_DISABLE_Q flag is not set
1108 		 */
1109 		if (_len) {
1110 			xgene_dma_prep_xor_desc(chan, new, &dst[1], _src,
1111 						src_cnt, &_len, scf);
1112 		}
1113 	} while (len || _len);
1114 
1115 	new->tx.flags = flags; /* client is in control of this ack */
1116 	new->tx.cookie = -EBUSY;
1117 	list_splice(&first->tx_list, &new->tx_list);
1118 
1119 	return &new->tx;
1120 
1121 fail:
1122 	if (!first)
1123 		return NULL;
1124 
1125 	xgene_dma_free_desc_list(chan, &first->tx_list);
1126 	return NULL;
1127 }
1128 
1129 static void xgene_dma_issue_pending(struct dma_chan *dchan)
1130 {
1131 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
1132 
1133 	spin_lock_bh(&chan->lock);
1134 	xgene_chan_xfer_ld_pending(chan);
1135 	spin_unlock_bh(&chan->lock);
1136 }
1137 
1138 static enum dma_status xgene_dma_tx_status(struct dma_chan *dchan,
1139 					   dma_cookie_t cookie,
1140 					   struct dma_tx_state *txstate)
1141 {
1142 	return dma_cookie_status(dchan, cookie, txstate);
1143 }
1144 
1145 static void xgene_dma_tasklet_cb(unsigned long data)
1146 {
1147 	struct xgene_dma_chan *chan = (struct xgene_dma_chan *)data;
1148 
1149 	/* Run all cleanup for descriptors which have been completed */
1150 	xgene_dma_cleanup_descriptors(chan);
1151 
1152 	/* Re-enable DMA channel IRQ */
1153 	enable_irq(chan->rx_irq);
1154 }
1155 
1156 static irqreturn_t xgene_dma_chan_ring_isr(int irq, void *id)
1157 {
1158 	struct xgene_dma_chan *chan = (struct xgene_dma_chan *)id;
1159 
1160 	BUG_ON(!chan);
1161 
1162 	/*
1163 	 * Disable DMA channel IRQ until we process completed
1164 	 * descriptors
1165 	 */
1166 	disable_irq_nosync(chan->rx_irq);
1167 
1168 	/*
1169 	 * Schedule the tasklet to handle all cleanup of the current
1170 	 * transaction. It will start a new transaction if there is
1171 	 * one pending.
1172 	 */
1173 	tasklet_schedule(&chan->tasklet);
1174 
1175 	return IRQ_HANDLED;
1176 }
1177 
1178 static irqreturn_t xgene_dma_err_isr(int irq, void *id)
1179 {
1180 	struct xgene_dma *pdma = (struct xgene_dma *)id;
1181 	unsigned long int_mask;
1182 	u32 val, i;
1183 
1184 	val = ioread32(pdma->csr_dma + XGENE_DMA_INT);
1185 
1186 	/* Clear DMA interrupts */
1187 	iowrite32(val, pdma->csr_dma + XGENE_DMA_INT);
1188 
1189 	/* Print DMA error info */
1190 	int_mask = val >> XGENE_DMA_INT_MASK_SHIFT;
1191 	for_each_set_bit(i, &int_mask, ARRAY_SIZE(xgene_dma_err))
1192 		dev_err(pdma->dev,
1193 			"Interrupt status 0x%08X %s\n", val, xgene_dma_err[i]);
1194 
1195 	return IRQ_HANDLED;
1196 }
1197 
1198 static void xgene_dma_wr_ring_state(struct xgene_dma_ring *ring)
1199 {
1200 	int i;
1201 
1202 	iowrite32(ring->num, ring->pdma->csr_ring + XGENE_DMA_RING_STATE);
1203 
1204 	for (i = 0; i < XGENE_DMA_RING_NUM_CONFIG; i++)
1205 		iowrite32(ring->state[i], ring->pdma->csr_ring +
1206 			  XGENE_DMA_RING_STATE_WR_BASE + (i * 4));
1207 }
1208 
1209 static void xgene_dma_clr_ring_state(struct xgene_dma_ring *ring)
1210 {
1211 	memset(ring->state, 0, sizeof(u32) * XGENE_DMA_RING_NUM_CONFIG);
1212 	xgene_dma_wr_ring_state(ring);
1213 }
1214 
1215 static void xgene_dma_setup_ring(struct xgene_dma_ring *ring)
1216 {
1217 	void *ring_cfg = ring->state;
1218 	u64 addr = ring->desc_paddr;
1219 	u32 i, val;
1220 
1221 	ring->slots = ring->size / XGENE_DMA_RING_WQ_DESC_SIZE;
1222 
1223 	/* Clear DMA ring state */
1224 	xgene_dma_clr_ring_state(ring);
1225 
1226 	/* Set DMA ring type */
1227 	XGENE_DMA_RING_TYPE_SET(ring_cfg, XGENE_DMA_RING_TYPE_REGULAR);
1228 
1229 	if (ring->owner == XGENE_DMA_RING_OWNER_DMA) {
1230 		/* Set recombination buffer and timeout */
1231 		XGENE_DMA_RING_RECOMBBUF_SET(ring_cfg);
1232 		XGENE_DMA_RING_RECOMTIMEOUTL_SET(ring_cfg);
1233 		XGENE_DMA_RING_RECOMTIMEOUTH_SET(ring_cfg);
1234 	}
1235 
1236 	/* Initialize DMA ring state */
1237 	XGENE_DMA_RING_SELTHRSH_SET(ring_cfg);
1238 	XGENE_DMA_RING_ACCEPTLERR_SET(ring_cfg);
1239 	XGENE_DMA_RING_COHERENT_SET(ring_cfg);
1240 	XGENE_DMA_RING_ADDRL_SET(ring_cfg, addr);
1241 	XGENE_DMA_RING_ADDRH_SET(ring_cfg, addr);
1242 	XGENE_DMA_RING_SIZE_SET(ring_cfg, ring->cfgsize);
1243 
1244 	/* Write DMA ring configurations */
1245 	xgene_dma_wr_ring_state(ring);
1246 
1247 	/* Set DMA ring id */
1248 	iowrite32(XGENE_DMA_RING_ID_SETUP(ring->id),
1249 		  ring->pdma->csr_ring + XGENE_DMA_RING_ID);
1250 
1251 	/* Set DMA ring buffer */
1252 	iowrite32(XGENE_DMA_RING_ID_BUF_SETUP(ring->num),
1253 		  ring->pdma->csr_ring + XGENE_DMA_RING_ID_BUF);
1254 
1255 	if (ring->owner != XGENE_DMA_RING_OWNER_CPU)
1256 		return;
1257 
1258 	/* Set empty signature to DMA Rx ring descriptors */
1259 	for (i = 0; i < ring->slots; i++) {
1260 		struct xgene_dma_desc_hw *desc;
1261 
1262 		desc = &ring->desc_hw[i];
1263 		desc->m0 = cpu_to_le64(XGENE_DMA_DESC_EMPTY_SIGNATURE);
1264 	}
1265 
1266 	/* Enable DMA Rx ring interrupt */
1267 	val = ioread32(ring->pdma->csr_ring + XGENE_DMA_RING_NE_INT_MODE);
1268 	XGENE_DMA_RING_NE_INT_MODE_SET(val, ring->buf_num);
1269 	iowrite32(val, ring->pdma->csr_ring + XGENE_DMA_RING_NE_INT_MODE);
1270 }
1271 
1272 static void xgene_dma_clear_ring(struct xgene_dma_ring *ring)
1273 {
1274 	u32 ring_id, val;
1275 
1276 	if (ring->owner == XGENE_DMA_RING_OWNER_CPU) {
1277 		/* Disable DMA Rx ring interrupt */
1278 		val = ioread32(ring->pdma->csr_ring +
1279 			       XGENE_DMA_RING_NE_INT_MODE);
1280 		XGENE_DMA_RING_NE_INT_MODE_RESET(val, ring->buf_num);
1281 		iowrite32(val, ring->pdma->csr_ring +
1282 			  XGENE_DMA_RING_NE_INT_MODE);
1283 	}
1284 
1285 	/* Clear DMA ring state */
1286 	ring_id = XGENE_DMA_RING_ID_SETUP(ring->id);
1287 	iowrite32(ring_id, ring->pdma->csr_ring + XGENE_DMA_RING_ID);
1288 
1289 	iowrite32(0, ring->pdma->csr_ring + XGENE_DMA_RING_ID_BUF);
1290 	xgene_dma_clr_ring_state(ring);
1291 }
1292 
1293 static void xgene_dma_set_ring_cmd(struct xgene_dma_ring *ring)
1294 {
1295 	ring->cmd_base = ring->pdma->csr_ring_cmd +
1296 				XGENE_DMA_RING_CMD_BASE_OFFSET((ring->num -
1297 							  XGENE_DMA_RING_NUM));
1298 
1299 	ring->cmd = ring->cmd_base + XGENE_DMA_RING_CMD_OFFSET;
1300 }
1301 
1302 static int xgene_dma_get_ring_size(struct xgene_dma_chan *chan,
1303 				   enum xgene_dma_ring_cfgsize cfgsize)
1304 {
1305 	int size;
1306 
1307 	switch (cfgsize) {
1308 	case XGENE_DMA_RING_CFG_SIZE_512B:
1309 		size = 0x200;
1310 		break;
1311 	case XGENE_DMA_RING_CFG_SIZE_2KB:
1312 		size = 0x800;
1313 		break;
1314 	case XGENE_DMA_RING_CFG_SIZE_16KB:
1315 		size = 0x4000;
1316 		break;
1317 	case XGENE_DMA_RING_CFG_SIZE_64KB:
1318 		size = 0x10000;
1319 		break;
1320 	case XGENE_DMA_RING_CFG_SIZE_512KB:
1321 		size = 0x80000;
1322 		break;
1323 	default:
1324 		chan_err(chan, "Unsupported cfg ring size %d\n", cfgsize);
1325 		return -EINVAL;
1326 	}
1327 
1328 	return size;
1329 }
1330 
1331 static void xgene_dma_delete_ring_one(struct xgene_dma_ring *ring)
1332 {
1333 	/* Clear DMA ring configurations */
1334 	xgene_dma_clear_ring(ring);
1335 
1336 	/* De-allocate DMA ring descriptor */
1337 	if (ring->desc_vaddr) {
1338 		dma_free_coherent(ring->pdma->dev, ring->size,
1339 				  ring->desc_vaddr, ring->desc_paddr);
1340 		ring->desc_vaddr = NULL;
1341 	}
1342 }
1343 
1344 static void xgene_dma_delete_chan_rings(struct xgene_dma_chan *chan)
1345 {
1346 	xgene_dma_delete_ring_one(&chan->rx_ring);
1347 	xgene_dma_delete_ring_one(&chan->tx_ring);
1348 }
1349 
1350 static int xgene_dma_create_ring_one(struct xgene_dma_chan *chan,
1351 				     struct xgene_dma_ring *ring,
1352 				     enum xgene_dma_ring_cfgsize cfgsize)
1353 {
1354 	int ret;
1355 
1356 	/* Setup DMA ring descriptor variables */
1357 	ring->pdma = chan->pdma;
1358 	ring->cfgsize = cfgsize;
1359 	ring->num = chan->pdma->ring_num++;
1360 	ring->id = XGENE_DMA_RING_ID_GET(ring->owner, ring->buf_num);
1361 
1362 	ret = xgene_dma_get_ring_size(chan, cfgsize);
1363 	if (ret <= 0)
1364 		return ret;
1365 	ring->size = ret;
1366 
1367 	/* Allocate memory for DMA ring descriptor */
1368 	ring->desc_vaddr = dma_zalloc_coherent(chan->dev, ring->size,
1369 					       &ring->desc_paddr, GFP_KERNEL);
1370 	if (!ring->desc_vaddr) {
1371 		chan_err(chan, "Failed to allocate ring desc\n");
1372 		return -ENOMEM;
1373 	}
1374 
1375 	/* Configure and enable DMA ring */
1376 	xgene_dma_set_ring_cmd(ring);
1377 	xgene_dma_setup_ring(ring);
1378 
1379 	return 0;
1380 }
1381 
1382 static int xgene_dma_create_chan_rings(struct xgene_dma_chan *chan)
1383 {
1384 	struct xgene_dma_ring *rx_ring = &chan->rx_ring;
1385 	struct xgene_dma_ring *tx_ring = &chan->tx_ring;
1386 	int ret;
1387 
1388 	/* Create DMA Rx ring descriptor */
1389 	rx_ring->owner = XGENE_DMA_RING_OWNER_CPU;
1390 	rx_ring->buf_num = XGENE_DMA_CPU_BUFNUM + chan->id;
1391 
1392 	ret = xgene_dma_create_ring_one(chan, rx_ring,
1393 					XGENE_DMA_RING_CFG_SIZE_64KB);
1394 	if (ret)
1395 		return ret;
1396 
1397 	chan_dbg(chan, "Rx ring id 0x%X num %d desc 0x%p\n",
1398 		 rx_ring->id, rx_ring->num, rx_ring->desc_vaddr);
1399 
1400 	/* Create DMA Tx ring descriptor */
1401 	tx_ring->owner = XGENE_DMA_RING_OWNER_DMA;
1402 	tx_ring->buf_num = XGENE_DMA_BUFNUM + chan->id;
1403 
1404 	ret = xgene_dma_create_ring_one(chan, tx_ring,
1405 					XGENE_DMA_RING_CFG_SIZE_64KB);
1406 	if (ret) {
1407 		xgene_dma_delete_ring_one(rx_ring);
1408 		return ret;
1409 	}
1410 
1411 	tx_ring->dst_ring_num = XGENE_DMA_RING_DST_ID(rx_ring->num);
1412 
1413 	chan_dbg(chan,
1414 		 "Tx ring id 0x%X num %d desc 0x%p\n",
1415 		 tx_ring->id, tx_ring->num, tx_ring->desc_vaddr);
1416 
1417 	/* Set the max outstanding request possible to this channel */
1418 	chan->max_outstanding = tx_ring->slots;
1419 
1420 	return ret;
1421 }
1422 
1423 static int xgene_dma_init_rings(struct xgene_dma *pdma)
1424 {
1425 	int ret, i, j;
1426 
1427 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1428 		ret = xgene_dma_create_chan_rings(&pdma->chan[i]);
1429 		if (ret) {
1430 			for (j = 0; j < i; j++)
1431 				xgene_dma_delete_chan_rings(&pdma->chan[j]);
1432 			return ret;
1433 		}
1434 	}
1435 
1436 	return ret;
1437 }
1438 
1439 static void xgene_dma_enable(struct xgene_dma *pdma)
1440 {
1441 	u32 val;
1442 
1443 	/* Configure and enable DMA engine */
1444 	val = ioread32(pdma->csr_dma + XGENE_DMA_GCR);
1445 	XGENE_DMA_CH_SETUP(val);
1446 	XGENE_DMA_ENABLE(val);
1447 	iowrite32(val, pdma->csr_dma + XGENE_DMA_GCR);
1448 }
1449 
1450 static void xgene_dma_disable(struct xgene_dma *pdma)
1451 {
1452 	u32 val;
1453 
1454 	val = ioread32(pdma->csr_dma + XGENE_DMA_GCR);
1455 	XGENE_DMA_DISABLE(val);
1456 	iowrite32(val, pdma->csr_dma + XGENE_DMA_GCR);
1457 }
1458 
1459 static void xgene_dma_mask_interrupts(struct xgene_dma *pdma)
1460 {
1461 	/*
1462 	 * Mask DMA ring overflow, underflow and
1463 	 * AXI write/read error interrupts
1464 	 */
1465 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1466 		  pdma->csr_dma + XGENE_DMA_RING_INT0_MASK);
1467 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1468 		  pdma->csr_dma + XGENE_DMA_RING_INT1_MASK);
1469 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1470 		  pdma->csr_dma + XGENE_DMA_RING_INT2_MASK);
1471 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1472 		  pdma->csr_dma + XGENE_DMA_RING_INT3_MASK);
1473 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1474 		  pdma->csr_dma + XGENE_DMA_RING_INT4_MASK);
1475 
1476 	/* Mask DMA error interrupts */
1477 	iowrite32(XGENE_DMA_INT_ALL_MASK, pdma->csr_dma + XGENE_DMA_INT_MASK);
1478 }
1479 
1480 static void xgene_dma_unmask_interrupts(struct xgene_dma *pdma)
1481 {
1482 	/*
1483 	 * Unmask DMA ring overflow, underflow and
1484 	 * AXI write/read error interrupts
1485 	 */
1486 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1487 		  pdma->csr_dma + XGENE_DMA_RING_INT0_MASK);
1488 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1489 		  pdma->csr_dma + XGENE_DMA_RING_INT1_MASK);
1490 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1491 		  pdma->csr_dma + XGENE_DMA_RING_INT2_MASK);
1492 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1493 		  pdma->csr_dma + XGENE_DMA_RING_INT3_MASK);
1494 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1495 		  pdma->csr_dma + XGENE_DMA_RING_INT4_MASK);
1496 
1497 	/* Unmask DMA error interrupts */
1498 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1499 		  pdma->csr_dma + XGENE_DMA_INT_MASK);
1500 }
1501 
1502 static void xgene_dma_init_hw(struct xgene_dma *pdma)
1503 {
1504 	u32 val;
1505 
1506 	/* Associate DMA ring to corresponding ring HW */
1507 	iowrite32(XGENE_DMA_ASSOC_RING_MNGR1,
1508 		  pdma->csr_dma + XGENE_DMA_CFG_RING_WQ_ASSOC);
1509 
1510 	/* Configure RAID6 polynomial control setting */
1511 	if (is_pq_enabled(pdma))
1512 		iowrite32(XGENE_DMA_RAID6_MULTI_CTRL(0x1D),
1513 			  pdma->csr_dma + XGENE_DMA_RAID6_CONT);
1514 	else
1515 		dev_info(pdma->dev, "PQ is disabled in HW\n");
1516 
1517 	xgene_dma_enable(pdma);
1518 	xgene_dma_unmask_interrupts(pdma);
1519 
1520 	/* Get DMA id and version info */
1521 	val = ioread32(pdma->csr_dma + XGENE_DMA_IPBRR);
1522 
1523 	/* DMA device info */
1524 	dev_info(pdma->dev,
1525 		 "X-Gene DMA v%d.%02d.%02d driver registered %d channels",
1526 		 XGENE_DMA_REV_NO_RD(val), XGENE_DMA_BUS_ID_RD(val),
1527 		 XGENE_DMA_DEV_ID_RD(val), XGENE_DMA_MAX_CHANNEL);
1528 }
1529 
1530 static int xgene_dma_init_ring_mngr(struct xgene_dma *pdma)
1531 {
1532 	if (ioread32(pdma->csr_ring + XGENE_DMA_RING_CLKEN) &&
1533 	    (!ioread32(pdma->csr_ring + XGENE_DMA_RING_SRST)))
1534 		return 0;
1535 
1536 	iowrite32(0x3, pdma->csr_ring + XGENE_DMA_RING_CLKEN);
1537 	iowrite32(0x0, pdma->csr_ring + XGENE_DMA_RING_SRST);
1538 
1539 	/* Bring up memory */
1540 	iowrite32(0x0, pdma->csr_ring + XGENE_DMA_RING_MEM_RAM_SHUTDOWN);
1541 
1542 	/* Force a barrier */
1543 	ioread32(pdma->csr_ring + XGENE_DMA_RING_MEM_RAM_SHUTDOWN);
1544 
1545 	/* reset may take up to 1ms */
1546 	usleep_range(1000, 1100);
1547 
1548 	if (ioread32(pdma->csr_ring + XGENE_DMA_RING_BLK_MEM_RDY)
1549 		!= XGENE_DMA_RING_BLK_MEM_RDY_VAL) {
1550 		dev_err(pdma->dev,
1551 			"Failed to release ring mngr memory from shutdown\n");
1552 		return -ENODEV;
1553 	}
1554 
1555 	/* program threshold set 1 and all hysteresis */
1556 	iowrite32(XGENE_DMA_RING_THRESLD0_SET1_VAL,
1557 		  pdma->csr_ring + XGENE_DMA_RING_THRESLD0_SET1);
1558 	iowrite32(XGENE_DMA_RING_THRESLD1_SET1_VAL,
1559 		  pdma->csr_ring + XGENE_DMA_RING_THRESLD1_SET1);
1560 	iowrite32(XGENE_DMA_RING_HYSTERESIS_VAL,
1561 		  pdma->csr_ring + XGENE_DMA_RING_HYSTERESIS);
1562 
1563 	/* Enable QPcore and assign error queue */
1564 	iowrite32(XGENE_DMA_RING_ENABLE,
1565 		  pdma->csr_ring + XGENE_DMA_RING_CONFIG);
1566 
1567 	return 0;
1568 }
1569 
1570 static int xgene_dma_init_mem(struct xgene_dma *pdma)
1571 {
1572 	int ret;
1573 
1574 	ret = xgene_dma_init_ring_mngr(pdma);
1575 	if (ret)
1576 		return ret;
1577 
1578 	/* Bring up memory */
1579 	iowrite32(0x0, pdma->csr_dma + XGENE_DMA_MEM_RAM_SHUTDOWN);
1580 
1581 	/* Force a barrier */
1582 	ioread32(pdma->csr_dma + XGENE_DMA_MEM_RAM_SHUTDOWN);
1583 
1584 	/* reset may take up to 1ms */
1585 	usleep_range(1000, 1100);
1586 
1587 	if (ioread32(pdma->csr_dma + XGENE_DMA_BLK_MEM_RDY)
1588 		!= XGENE_DMA_BLK_MEM_RDY_VAL) {
1589 		dev_err(pdma->dev,
1590 			"Failed to release DMA memory from shutdown\n");
1591 		return -ENODEV;
1592 	}
1593 
1594 	return 0;
1595 }
1596 
1597 static int xgene_dma_request_irqs(struct xgene_dma *pdma)
1598 {
1599 	struct xgene_dma_chan *chan;
1600 	int ret, i, j;
1601 
1602 	/* Register DMA error irq */
1603 	ret = devm_request_irq(pdma->dev, pdma->err_irq, xgene_dma_err_isr,
1604 			       0, "dma_error", pdma);
1605 	if (ret) {
1606 		dev_err(pdma->dev,
1607 			"Failed to register error IRQ %d\n", pdma->err_irq);
1608 		return ret;
1609 	}
1610 
1611 	/* Register DMA channel rx irq */
1612 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1613 		chan = &pdma->chan[i];
1614 		irq_set_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1615 		ret = devm_request_irq(chan->dev, chan->rx_irq,
1616 				       xgene_dma_chan_ring_isr,
1617 				       0, chan->name, chan);
1618 		if (ret) {
1619 			chan_err(chan, "Failed to register Rx IRQ %d\n",
1620 				 chan->rx_irq);
1621 			devm_free_irq(pdma->dev, pdma->err_irq, pdma);
1622 
1623 			for (j = 0; j < i; j++) {
1624 				chan = &pdma->chan[i];
1625 				irq_clear_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1626 				devm_free_irq(chan->dev, chan->rx_irq, chan);
1627 			}
1628 
1629 			return ret;
1630 		}
1631 	}
1632 
1633 	return 0;
1634 }
1635 
1636 static void xgene_dma_free_irqs(struct xgene_dma *pdma)
1637 {
1638 	struct xgene_dma_chan *chan;
1639 	int i;
1640 
1641 	/* Free DMA device error irq */
1642 	devm_free_irq(pdma->dev, pdma->err_irq, pdma);
1643 
1644 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1645 		chan = &pdma->chan[i];
1646 		irq_clear_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1647 		devm_free_irq(chan->dev, chan->rx_irq, chan);
1648 	}
1649 }
1650 
1651 static void xgene_dma_set_caps(struct xgene_dma_chan *chan,
1652 			       struct dma_device *dma_dev)
1653 {
1654 	/* Initialize DMA device capability mask */
1655 	dma_cap_zero(dma_dev->cap_mask);
1656 
1657 	/* Set DMA device capability */
1658 	dma_cap_set(DMA_SG, dma_dev->cap_mask);
1659 
1660 	/* Basically here, the X-Gene SoC DMA engine channel 0 supports XOR
1661 	 * and channel 1 supports XOR, PQ both. First thing here is we have
1662 	 * mechanism in hw to enable/disable PQ/XOR supports on channel 1,
1663 	 * we can make sure this by reading SoC Efuse register.
1664 	 * Second thing, we have hw errata that if we run channel 0 and
1665 	 * channel 1 simultaneously with executing XOR and PQ request,
1666 	 * suddenly DMA engine hangs, So here we enable XOR on channel 0 only
1667 	 * if XOR and PQ supports on channel 1 is disabled.
1668 	 */
1669 	if ((chan->id == XGENE_DMA_PQ_CHANNEL) &&
1670 	    is_pq_enabled(chan->pdma)) {
1671 		dma_cap_set(DMA_PQ, dma_dev->cap_mask);
1672 		dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1673 	} else if ((chan->id == XGENE_DMA_XOR_CHANNEL) &&
1674 		   !is_pq_enabled(chan->pdma)) {
1675 		dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1676 	}
1677 
1678 	/* Set base and prep routines */
1679 	dma_dev->dev = chan->dev;
1680 	dma_dev->device_alloc_chan_resources = xgene_dma_alloc_chan_resources;
1681 	dma_dev->device_free_chan_resources = xgene_dma_free_chan_resources;
1682 	dma_dev->device_issue_pending = xgene_dma_issue_pending;
1683 	dma_dev->device_tx_status = xgene_dma_tx_status;
1684 	dma_dev->device_prep_dma_sg = xgene_dma_prep_sg;
1685 
1686 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1687 		dma_dev->device_prep_dma_xor = xgene_dma_prep_xor;
1688 		dma_dev->max_xor = XGENE_DMA_MAX_XOR_SRC;
1689 		dma_dev->xor_align = DMAENGINE_ALIGN_64_BYTES;
1690 	}
1691 
1692 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
1693 		dma_dev->device_prep_dma_pq = xgene_dma_prep_pq;
1694 		dma_dev->max_pq = XGENE_DMA_MAX_XOR_SRC;
1695 		dma_dev->pq_align = DMAENGINE_ALIGN_64_BYTES;
1696 	}
1697 }
1698 
1699 static int xgene_dma_async_register(struct xgene_dma *pdma, int id)
1700 {
1701 	struct xgene_dma_chan *chan = &pdma->chan[id];
1702 	struct dma_device *dma_dev = &pdma->dma_dev[id];
1703 	int ret;
1704 
1705 	chan->dma_chan.device = dma_dev;
1706 
1707 	spin_lock_init(&chan->lock);
1708 	INIT_LIST_HEAD(&chan->ld_pending);
1709 	INIT_LIST_HEAD(&chan->ld_running);
1710 	INIT_LIST_HEAD(&chan->ld_completed);
1711 	tasklet_init(&chan->tasklet, xgene_dma_tasklet_cb,
1712 		     (unsigned long)chan);
1713 
1714 	chan->pending = 0;
1715 	chan->desc_pool = NULL;
1716 	dma_cookie_init(&chan->dma_chan);
1717 
1718 	/* Setup dma device capabilities and prep routines */
1719 	xgene_dma_set_caps(chan, dma_dev);
1720 
1721 	/* Initialize DMA device list head */
1722 	INIT_LIST_HEAD(&dma_dev->channels);
1723 	list_add_tail(&chan->dma_chan.device_node, &dma_dev->channels);
1724 
1725 	/* Register with Linux async DMA framework*/
1726 	ret = dma_async_device_register(dma_dev);
1727 	if (ret) {
1728 		chan_err(chan, "Failed to register async device %d", ret);
1729 		tasklet_kill(&chan->tasklet);
1730 
1731 		return ret;
1732 	}
1733 
1734 	/* DMA capability info */
1735 	dev_info(pdma->dev,
1736 		 "%s: CAPABILITY ( %s%s%s)\n", dma_chan_name(&chan->dma_chan),
1737 		 dma_has_cap(DMA_SG, dma_dev->cap_mask) ? "SGCPY " : "",
1738 		 dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "XOR " : "",
1739 		 dma_has_cap(DMA_PQ, dma_dev->cap_mask) ? "PQ " : "");
1740 
1741 	return 0;
1742 }
1743 
1744 static int xgene_dma_init_async(struct xgene_dma *pdma)
1745 {
1746 	int ret, i, j;
1747 
1748 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL ; i++) {
1749 		ret = xgene_dma_async_register(pdma, i);
1750 		if (ret) {
1751 			for (j = 0; j < i; j++) {
1752 				dma_async_device_unregister(&pdma->dma_dev[j]);
1753 				tasklet_kill(&pdma->chan[j].tasklet);
1754 			}
1755 
1756 			return ret;
1757 		}
1758 	}
1759 
1760 	return ret;
1761 }
1762 
1763 static void xgene_dma_async_unregister(struct xgene_dma *pdma)
1764 {
1765 	int i;
1766 
1767 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++)
1768 		dma_async_device_unregister(&pdma->dma_dev[i]);
1769 }
1770 
1771 static void xgene_dma_init_channels(struct xgene_dma *pdma)
1772 {
1773 	struct xgene_dma_chan *chan;
1774 	int i;
1775 
1776 	pdma->ring_num = XGENE_DMA_RING_NUM;
1777 
1778 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1779 		chan = &pdma->chan[i];
1780 		chan->dev = pdma->dev;
1781 		chan->pdma = pdma;
1782 		chan->id = i;
1783 		snprintf(chan->name, sizeof(chan->name), "dmachan%d", chan->id);
1784 	}
1785 }
1786 
1787 static int xgene_dma_get_resources(struct platform_device *pdev,
1788 				   struct xgene_dma *pdma)
1789 {
1790 	struct resource *res;
1791 	int irq, i;
1792 
1793 	/* Get DMA csr region */
1794 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1795 	if (!res) {
1796 		dev_err(&pdev->dev, "Failed to get csr region\n");
1797 		return -ENXIO;
1798 	}
1799 
1800 	pdma->csr_dma = devm_ioremap(&pdev->dev, res->start,
1801 				     resource_size(res));
1802 	if (!pdma->csr_dma) {
1803 		dev_err(&pdev->dev, "Failed to ioremap csr region");
1804 		return -ENOMEM;
1805 	}
1806 
1807 	/* Get DMA ring csr region */
1808 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1809 	if (!res) {
1810 		dev_err(&pdev->dev, "Failed to get ring csr region\n");
1811 		return -ENXIO;
1812 	}
1813 
1814 	pdma->csr_ring =  devm_ioremap(&pdev->dev, res->start,
1815 				       resource_size(res));
1816 	if (!pdma->csr_ring) {
1817 		dev_err(&pdev->dev, "Failed to ioremap ring csr region");
1818 		return -ENOMEM;
1819 	}
1820 
1821 	/* Get DMA ring cmd csr region */
1822 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
1823 	if (!res) {
1824 		dev_err(&pdev->dev, "Failed to get ring cmd csr region\n");
1825 		return -ENXIO;
1826 	}
1827 
1828 	pdma->csr_ring_cmd = devm_ioremap(&pdev->dev, res->start,
1829 					  resource_size(res));
1830 	if (!pdma->csr_ring_cmd) {
1831 		dev_err(&pdev->dev, "Failed to ioremap ring cmd csr region");
1832 		return -ENOMEM;
1833 	}
1834 
1835 	pdma->csr_ring_cmd += XGENE_DMA_RING_CMD_SM_OFFSET;
1836 
1837 	/* Get efuse csr region */
1838 	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
1839 	if (!res) {
1840 		dev_err(&pdev->dev, "Failed to get efuse csr region\n");
1841 		return -ENXIO;
1842 	}
1843 
1844 	pdma->csr_efuse = devm_ioremap(&pdev->dev, res->start,
1845 				       resource_size(res));
1846 	if (!pdma->csr_efuse) {
1847 		dev_err(&pdev->dev, "Failed to ioremap efuse csr region");
1848 		return -ENOMEM;
1849 	}
1850 
1851 	/* Get DMA error interrupt */
1852 	irq = platform_get_irq(pdev, 0);
1853 	if (irq <= 0) {
1854 		dev_err(&pdev->dev, "Failed to get Error IRQ\n");
1855 		return -ENXIO;
1856 	}
1857 
1858 	pdma->err_irq = irq;
1859 
1860 	/* Get DMA Rx ring descriptor interrupts for all DMA channels */
1861 	for (i = 1; i <= XGENE_DMA_MAX_CHANNEL; i++) {
1862 		irq = platform_get_irq(pdev, i);
1863 		if (irq <= 0) {
1864 			dev_err(&pdev->dev, "Failed to get Rx IRQ\n");
1865 			return -ENXIO;
1866 		}
1867 
1868 		pdma->chan[i - 1].rx_irq = irq;
1869 	}
1870 
1871 	return 0;
1872 }
1873 
1874 static int xgene_dma_probe(struct platform_device *pdev)
1875 {
1876 	struct xgene_dma *pdma;
1877 	int ret, i;
1878 
1879 	pdma = devm_kzalloc(&pdev->dev, sizeof(*pdma), GFP_KERNEL);
1880 	if (!pdma)
1881 		return -ENOMEM;
1882 
1883 	pdma->dev = &pdev->dev;
1884 	platform_set_drvdata(pdev, pdma);
1885 
1886 	ret = xgene_dma_get_resources(pdev, pdma);
1887 	if (ret)
1888 		return ret;
1889 
1890 	pdma->clk = devm_clk_get(&pdev->dev, NULL);
1891 	if (IS_ERR(pdma->clk) && !ACPI_COMPANION(&pdev->dev)) {
1892 		dev_err(&pdev->dev, "Failed to get clk\n");
1893 		return PTR_ERR(pdma->clk);
1894 	}
1895 
1896 	/* Enable clk before accessing registers */
1897 	if (!IS_ERR(pdma->clk)) {
1898 		ret = clk_prepare_enable(pdma->clk);
1899 		if (ret) {
1900 			dev_err(&pdev->dev, "Failed to enable clk %d\n", ret);
1901 			return ret;
1902 		}
1903 	}
1904 
1905 	/* Remove DMA RAM out of shutdown */
1906 	ret = xgene_dma_init_mem(pdma);
1907 	if (ret)
1908 		goto err_clk_enable;
1909 
1910 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(42));
1911 	if (ret) {
1912 		dev_err(&pdev->dev, "No usable DMA configuration\n");
1913 		goto err_dma_mask;
1914 	}
1915 
1916 	/* Initialize DMA channels software state */
1917 	xgene_dma_init_channels(pdma);
1918 
1919 	/* Configue DMA rings */
1920 	ret = xgene_dma_init_rings(pdma);
1921 	if (ret)
1922 		goto err_clk_enable;
1923 
1924 	ret = xgene_dma_request_irqs(pdma);
1925 	if (ret)
1926 		goto err_request_irq;
1927 
1928 	/* Configure and enable DMA engine */
1929 	xgene_dma_init_hw(pdma);
1930 
1931 	/* Register DMA device with linux async framework */
1932 	ret = xgene_dma_init_async(pdma);
1933 	if (ret)
1934 		goto err_async_init;
1935 
1936 	return 0;
1937 
1938 err_async_init:
1939 	xgene_dma_free_irqs(pdma);
1940 
1941 err_request_irq:
1942 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++)
1943 		xgene_dma_delete_chan_rings(&pdma->chan[i]);
1944 
1945 err_dma_mask:
1946 err_clk_enable:
1947 	if (!IS_ERR(pdma->clk))
1948 		clk_disable_unprepare(pdma->clk);
1949 
1950 	return ret;
1951 }
1952 
1953 static int xgene_dma_remove(struct platform_device *pdev)
1954 {
1955 	struct xgene_dma *pdma = platform_get_drvdata(pdev);
1956 	struct xgene_dma_chan *chan;
1957 	int i;
1958 
1959 	xgene_dma_async_unregister(pdma);
1960 
1961 	/* Mask interrupts and disable DMA engine */
1962 	xgene_dma_mask_interrupts(pdma);
1963 	xgene_dma_disable(pdma);
1964 	xgene_dma_free_irqs(pdma);
1965 
1966 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1967 		chan = &pdma->chan[i];
1968 		tasklet_kill(&chan->tasklet);
1969 		xgene_dma_delete_chan_rings(chan);
1970 	}
1971 
1972 	if (!IS_ERR(pdma->clk))
1973 		clk_disable_unprepare(pdma->clk);
1974 
1975 	return 0;
1976 }
1977 
1978 #ifdef CONFIG_ACPI
1979 static const struct acpi_device_id xgene_dma_acpi_match_ptr[] = {
1980 	{"APMC0D43", 0},
1981 	{},
1982 };
1983 MODULE_DEVICE_TABLE(acpi, xgene_dma_acpi_match_ptr);
1984 #endif
1985 
1986 static const struct of_device_id xgene_dma_of_match_ptr[] = {
1987 	{.compatible = "apm,xgene-storm-dma",},
1988 	{},
1989 };
1990 MODULE_DEVICE_TABLE(of, xgene_dma_of_match_ptr);
1991 
1992 static struct platform_driver xgene_dma_driver = {
1993 	.probe = xgene_dma_probe,
1994 	.remove = xgene_dma_remove,
1995 	.driver = {
1996 		.name = "X-Gene-DMA",
1997 		.of_match_table = xgene_dma_of_match_ptr,
1998 		.acpi_match_table = ACPI_PTR(xgene_dma_acpi_match_ptr),
1999 	},
2000 };
2001 
2002 module_platform_driver(xgene_dma_driver);
2003 
2004 MODULE_DESCRIPTION("APM X-Gene SoC DMA driver");
2005 MODULE_AUTHOR("Rameshwar Prasad Sahu <rsahu@apm.com>");
2006 MODULE_AUTHOR("Loc Ho <lho@apm.com>");
2007 MODULE_LICENSE("GPL");
2008 MODULE_VERSION("1.0");
2009