xref: /linux/drivers/dma/xgene-dma.c (revision 7aacf86b75bc5523d20fd9127104384fce51ce9c)
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 	dma_descriptor_unmap(tx);
610 
611 	/* Run the link descriptor callback function */
612 	dmaengine_desc_get_callback_invoke(tx, NULL);
613 
614 	/* Run any dependencies */
615 	dma_run_dependencies(tx);
616 }
617 
618 /**
619  * xgene_dma_clean_running_descriptor - move the completed descriptor from
620  * ld_running to ld_completed
621  * @chan: X-Gene DMA channel
622  * @desc: the descriptor which is completed
623  *
624  * Free the descriptor directly if acked by async_tx api,
625  * else move it to queue ld_completed.
626  */
627 static void xgene_dma_clean_running_descriptor(struct xgene_dma_chan *chan,
628 					       struct xgene_dma_desc_sw *desc)
629 {
630 	/* Remove from the list of running transactions */
631 	list_del(&desc->node);
632 
633 	/*
634 	 * the client is allowed to attach dependent operations
635 	 * until 'ack' is set
636 	 */
637 	if (!async_tx_test_ack(&desc->tx)) {
638 		/*
639 		 * Move this descriptor to the list of descriptors which is
640 		 * completed, but still awaiting the 'ack' bit to be set.
641 		 */
642 		list_add_tail(&desc->node, &chan->ld_completed);
643 		return;
644 	}
645 
646 	chan_dbg(chan, "LD %p free\n", desc);
647 	dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
648 }
649 
650 static void xgene_chan_xfer_request(struct xgene_dma_chan *chan,
651 				    struct xgene_dma_desc_sw *desc_sw)
652 {
653 	struct xgene_dma_ring *ring = &chan->tx_ring;
654 	struct xgene_dma_desc_hw *desc_hw;
655 
656 	/* Get hw descriptor from DMA tx ring */
657 	desc_hw = &ring->desc_hw[ring->head];
658 
659 	/*
660 	 * Increment the head count to point next
661 	 * descriptor for next time
662 	 */
663 	if (++ring->head == ring->slots)
664 		ring->head = 0;
665 
666 	/* Copy prepared sw descriptor data to hw descriptor */
667 	memcpy(desc_hw, &desc_sw->desc1, sizeof(*desc_hw));
668 
669 	/*
670 	 * Check if we have prepared 64B descriptor,
671 	 * in this case we need one more hw descriptor
672 	 */
673 	if (desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) {
674 		desc_hw = &ring->desc_hw[ring->head];
675 
676 		if (++ring->head == ring->slots)
677 			ring->head = 0;
678 
679 		memcpy(desc_hw, &desc_sw->desc2, sizeof(*desc_hw));
680 	}
681 
682 	/* Increment the pending transaction count */
683 	chan->pending += ((desc_sw->flags &
684 			  XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
685 
686 	/* Notify the hw that we have descriptor ready for execution */
687 	iowrite32((desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) ?
688 		  2 : 1, ring->cmd);
689 }
690 
691 /**
692  * xgene_chan_xfer_ld_pending - push any pending transactions to hw
693  * @chan : X-Gene DMA channel
694  *
695  * LOCKING: must hold chan->lock
696  */
697 static void xgene_chan_xfer_ld_pending(struct xgene_dma_chan *chan)
698 {
699 	struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
700 
701 	/*
702 	 * If the list of pending descriptors is empty, then we
703 	 * don't need to do any work at all
704 	 */
705 	if (list_empty(&chan->ld_pending)) {
706 		chan_dbg(chan, "No pending LDs\n");
707 		return;
708 	}
709 
710 	/*
711 	 * Move elements from the queue of pending transactions onto the list
712 	 * of running transactions and push it to hw for further executions
713 	 */
714 	list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_pending, node) {
715 		/*
716 		 * Check if have pushed max number of transactions to hw
717 		 * as capable, so let's stop here and will push remaining
718 		 * elements from pening ld queue after completing some
719 		 * descriptors that we have already pushed
720 		 */
721 		if (chan->pending >= chan->max_outstanding)
722 			return;
723 
724 		xgene_chan_xfer_request(chan, desc_sw);
725 
726 		/*
727 		 * Delete this element from ld pending queue and append it to
728 		 * ld running queue
729 		 */
730 		list_move_tail(&desc_sw->node, &chan->ld_running);
731 	}
732 }
733 
734 /**
735  * xgene_dma_cleanup_descriptors - cleanup link descriptors which are completed
736  * and move them to ld_completed to free until flag 'ack' is set
737  * @chan: X-Gene DMA channel
738  *
739  * This function is used on descriptors which have been executed by the DMA
740  * controller. It will run any callbacks, submit any dependencies, then
741  * free these descriptors if flag 'ack' is set.
742  */
743 static void xgene_dma_cleanup_descriptors(struct xgene_dma_chan *chan)
744 {
745 	struct xgene_dma_ring *ring = &chan->rx_ring;
746 	struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
747 	struct xgene_dma_desc_hw *desc_hw;
748 	struct list_head ld_completed;
749 	u8 status;
750 
751 	INIT_LIST_HEAD(&ld_completed);
752 
753 	spin_lock_bh(&chan->lock);
754 
755 	/* Clean already completed and acked descriptors */
756 	xgene_dma_clean_completed_descriptor(chan);
757 
758 	/* Move all completed descriptors to ld completed queue, in order */
759 	list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_running, node) {
760 		/* Get subsequent hw descriptor from DMA rx ring */
761 		desc_hw = &ring->desc_hw[ring->head];
762 
763 		/* Check if this descriptor has been completed */
764 		if (unlikely(le64_to_cpu(desc_hw->m0) ==
765 			     XGENE_DMA_DESC_EMPTY_SIGNATURE))
766 			break;
767 
768 		if (++ring->head == ring->slots)
769 			ring->head = 0;
770 
771 		/* Check if we have any error with DMA transactions */
772 		status = XGENE_DMA_DESC_STATUS(
773 				XGENE_DMA_DESC_ELERR_RD(le64_to_cpu(
774 							desc_hw->m0)),
775 				XGENE_DMA_DESC_LERR_RD(le64_to_cpu(
776 						       desc_hw->m0)));
777 		if (status) {
778 			/* Print the DMA error type */
779 			chan_err(chan, "%s\n", xgene_dma_desc_err[status]);
780 
781 			/*
782 			 * We have DMA transactions error here. Dump DMA Tx
783 			 * and Rx descriptors for this request */
784 			XGENE_DMA_DESC_DUMP(&desc_sw->desc1,
785 					    "X-Gene DMA TX DESC1: ");
786 
787 			if (desc_sw->flags & XGENE_DMA_FLAG_64B_DESC)
788 				XGENE_DMA_DESC_DUMP(&desc_sw->desc2,
789 						    "X-Gene DMA TX DESC2: ");
790 
791 			XGENE_DMA_DESC_DUMP(desc_hw,
792 					    "X-Gene DMA RX ERR DESC: ");
793 		}
794 
795 		/* Notify the hw about this completed descriptor */
796 		iowrite32(-1, ring->cmd);
797 
798 		/* Mark this hw descriptor as processed */
799 		desc_hw->m0 = cpu_to_le64(XGENE_DMA_DESC_EMPTY_SIGNATURE);
800 
801 		/*
802 		 * Decrement the pending transaction count
803 		 * as we have processed one
804 		 */
805 		chan->pending -= ((desc_sw->flags &
806 				  XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
807 
808 		/*
809 		 * Delete this node from ld running queue and append it to
810 		 * ld completed queue for further processing
811 		 */
812 		list_move_tail(&desc_sw->node, &ld_completed);
813 	}
814 
815 	/*
816 	 * Start any pending transactions automatically
817 	 * In the ideal case, we keep the DMA controller busy while we go
818 	 * ahead and free the descriptors below.
819 	 */
820 	xgene_chan_xfer_ld_pending(chan);
821 
822 	spin_unlock_bh(&chan->lock);
823 
824 	/* Run the callback for each descriptor, in order */
825 	list_for_each_entry_safe(desc_sw, _desc_sw, &ld_completed, node) {
826 		xgene_dma_run_tx_complete_actions(chan, desc_sw);
827 		xgene_dma_clean_running_descriptor(chan, desc_sw);
828 	}
829 }
830 
831 static int xgene_dma_alloc_chan_resources(struct dma_chan *dchan)
832 {
833 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
834 
835 	/* Has this channel already been allocated? */
836 	if (chan->desc_pool)
837 		return 1;
838 
839 	chan->desc_pool = dma_pool_create(chan->name, chan->dev,
840 					  sizeof(struct xgene_dma_desc_sw),
841 					  0, 0);
842 	if (!chan->desc_pool) {
843 		chan_err(chan, "Failed to allocate descriptor pool\n");
844 		return -ENOMEM;
845 	}
846 
847 	chan_dbg(chan, "Allocate descripto pool\n");
848 
849 	return 1;
850 }
851 
852 /**
853  * xgene_dma_free_desc_list - Free all descriptors in a queue
854  * @chan: X-Gene DMA channel
855  * @list: the list to free
856  *
857  * LOCKING: must hold chan->lock
858  */
859 static void xgene_dma_free_desc_list(struct xgene_dma_chan *chan,
860 				     struct list_head *list)
861 {
862 	struct xgene_dma_desc_sw *desc, *_desc;
863 
864 	list_for_each_entry_safe(desc, _desc, list, node)
865 		xgene_dma_clean_descriptor(chan, desc);
866 }
867 
868 static void xgene_dma_free_chan_resources(struct dma_chan *dchan)
869 {
870 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
871 
872 	chan_dbg(chan, "Free all resources\n");
873 
874 	if (!chan->desc_pool)
875 		return;
876 
877 	/* Process all running descriptor */
878 	xgene_dma_cleanup_descriptors(chan);
879 
880 	spin_lock_bh(&chan->lock);
881 
882 	/* Clean all link descriptor queues */
883 	xgene_dma_free_desc_list(chan, &chan->ld_pending);
884 	xgene_dma_free_desc_list(chan, &chan->ld_running);
885 	xgene_dma_free_desc_list(chan, &chan->ld_completed);
886 
887 	spin_unlock_bh(&chan->lock);
888 
889 	/* Delete this channel DMA pool */
890 	dma_pool_destroy(chan->desc_pool);
891 	chan->desc_pool = NULL;
892 }
893 
894 static struct dma_async_tx_descriptor *xgene_dma_prep_sg(
895 	struct dma_chan *dchan, struct scatterlist *dst_sg,
896 	u32 dst_nents, struct scatterlist *src_sg,
897 	u32 src_nents, unsigned long flags)
898 {
899 	struct xgene_dma_desc_sw *first = NULL, *new = NULL;
900 	struct xgene_dma_chan *chan;
901 	size_t dst_avail, src_avail;
902 	dma_addr_t dst, src;
903 	size_t len;
904 
905 	if (unlikely(!dchan))
906 		return NULL;
907 
908 	if (unlikely(!dst_nents || !src_nents))
909 		return NULL;
910 
911 	if (unlikely(!dst_sg || !src_sg))
912 		return NULL;
913 
914 	chan = to_dma_chan(dchan);
915 
916 	/* Get prepared for the loop */
917 	dst_avail = sg_dma_len(dst_sg);
918 	src_avail = sg_dma_len(src_sg);
919 	dst_nents--;
920 	src_nents--;
921 
922 	/* Run until we are out of scatterlist entries */
923 	while (true) {
924 		/* Create the largest transaction possible */
925 		len = min_t(size_t, src_avail, dst_avail);
926 		len = min_t(size_t, len, XGENE_DMA_MAX_64B_DESC_BYTE_CNT);
927 		if (len == 0)
928 			goto fetch;
929 
930 		dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) - dst_avail;
931 		src = sg_dma_address(src_sg) + sg_dma_len(src_sg) - src_avail;
932 
933 		/* Allocate the link descriptor from DMA pool */
934 		new = xgene_dma_alloc_descriptor(chan);
935 		if (!new)
936 			goto fail;
937 
938 		/* Prepare DMA descriptor */
939 		xgene_dma_prep_cpy_desc(chan, new, dst, src, len);
940 
941 		if (!first)
942 			first = new;
943 
944 		new->tx.cookie = 0;
945 		async_tx_ack(&new->tx);
946 
947 		/* update metadata */
948 		dst_avail -= len;
949 		src_avail -= len;
950 
951 		/* Insert the link descriptor to the LD ring */
952 		list_add_tail(&new->node, &first->tx_list);
953 
954 fetch:
955 		/* fetch the next dst scatterlist entry */
956 		if (dst_avail == 0) {
957 			/* no more entries: we're done */
958 			if (dst_nents == 0)
959 				break;
960 
961 			/* fetch the next entry: if there are no more: done */
962 			dst_sg = sg_next(dst_sg);
963 			if (!dst_sg)
964 				break;
965 
966 			dst_nents--;
967 			dst_avail = sg_dma_len(dst_sg);
968 		}
969 
970 		/* fetch the next src scatterlist entry */
971 		if (src_avail == 0) {
972 			/* no more entries: we're done */
973 			if (src_nents == 0)
974 				break;
975 
976 			/* fetch the next entry: if there are no more: done */
977 			src_sg = sg_next(src_sg);
978 			if (!src_sg)
979 				break;
980 
981 			src_nents--;
982 			src_avail = sg_dma_len(src_sg);
983 		}
984 	}
985 
986 	if (!new)
987 		return NULL;
988 
989 	new->tx.flags = flags; /* client is in control of this ack */
990 	new->tx.cookie = -EBUSY;
991 	list_splice(&first->tx_list, &new->tx_list);
992 
993 	return &new->tx;
994 fail:
995 	if (!first)
996 		return NULL;
997 
998 	xgene_dma_free_desc_list(chan, &first->tx_list);
999 	return NULL;
1000 }
1001 
1002 static struct dma_async_tx_descriptor *xgene_dma_prep_xor(
1003 	struct dma_chan *dchan, dma_addr_t dst,	dma_addr_t *src,
1004 	u32 src_cnt, size_t len, unsigned long flags)
1005 {
1006 	struct xgene_dma_desc_sw *first = NULL, *new;
1007 	struct xgene_dma_chan *chan;
1008 	static u8 multi[XGENE_DMA_MAX_XOR_SRC] = {
1009 				0x01, 0x01, 0x01, 0x01, 0x01};
1010 
1011 	if (unlikely(!dchan || !len))
1012 		return NULL;
1013 
1014 	chan = to_dma_chan(dchan);
1015 
1016 	do {
1017 		/* Allocate the link descriptor from DMA pool */
1018 		new = xgene_dma_alloc_descriptor(chan);
1019 		if (!new)
1020 			goto fail;
1021 
1022 		/* Prepare xor DMA descriptor */
1023 		xgene_dma_prep_xor_desc(chan, new, &dst, src,
1024 					src_cnt, &len, multi);
1025 
1026 		if (!first)
1027 			first = new;
1028 
1029 		new->tx.cookie = 0;
1030 		async_tx_ack(&new->tx);
1031 
1032 		/* Insert the link descriptor to the LD ring */
1033 		list_add_tail(&new->node, &first->tx_list);
1034 	} while (len);
1035 
1036 	new->tx.flags = flags; /* client is in control of this ack */
1037 	new->tx.cookie = -EBUSY;
1038 	list_splice(&first->tx_list, &new->tx_list);
1039 
1040 	return &new->tx;
1041 
1042 fail:
1043 	if (!first)
1044 		return NULL;
1045 
1046 	xgene_dma_free_desc_list(chan, &first->tx_list);
1047 	return NULL;
1048 }
1049 
1050 static struct dma_async_tx_descriptor *xgene_dma_prep_pq(
1051 	struct dma_chan *dchan, dma_addr_t *dst, dma_addr_t *src,
1052 	u32 src_cnt, const u8 *scf, size_t len, unsigned long flags)
1053 {
1054 	struct xgene_dma_desc_sw *first = NULL, *new;
1055 	struct xgene_dma_chan *chan;
1056 	size_t _len = len;
1057 	dma_addr_t _src[XGENE_DMA_MAX_XOR_SRC];
1058 	static u8 multi[XGENE_DMA_MAX_XOR_SRC] = {0x01, 0x01, 0x01, 0x01, 0x01};
1059 
1060 	if (unlikely(!dchan || !len))
1061 		return NULL;
1062 
1063 	chan = to_dma_chan(dchan);
1064 
1065 	/*
1066 	 * Save source addresses on local variable, may be we have to
1067 	 * prepare two descriptor to generate P and Q if both enabled
1068 	 * in the flags by client
1069 	 */
1070 	memcpy(_src, src, sizeof(*src) * src_cnt);
1071 
1072 	if (flags & DMA_PREP_PQ_DISABLE_P)
1073 		len = 0;
1074 
1075 	if (flags & DMA_PREP_PQ_DISABLE_Q)
1076 		_len = 0;
1077 
1078 	do {
1079 		/* Allocate the link descriptor from DMA pool */
1080 		new = xgene_dma_alloc_descriptor(chan);
1081 		if (!new)
1082 			goto fail;
1083 
1084 		if (!first)
1085 			first = new;
1086 
1087 		new->tx.cookie = 0;
1088 		async_tx_ack(&new->tx);
1089 
1090 		/* Insert the link descriptor to the LD ring */
1091 		list_add_tail(&new->node, &first->tx_list);
1092 
1093 		/*
1094 		 * Prepare DMA descriptor to generate P,
1095 		 * if DMA_PREP_PQ_DISABLE_P flag is not set
1096 		 */
1097 		if (len) {
1098 			xgene_dma_prep_xor_desc(chan, new, &dst[0], src,
1099 						src_cnt, &len, multi);
1100 			continue;
1101 		}
1102 
1103 		/*
1104 		 * Prepare DMA descriptor to generate Q,
1105 		 * if DMA_PREP_PQ_DISABLE_Q flag is not set
1106 		 */
1107 		if (_len) {
1108 			xgene_dma_prep_xor_desc(chan, new, &dst[1], _src,
1109 						src_cnt, &_len, scf);
1110 		}
1111 	} while (len || _len);
1112 
1113 	new->tx.flags = flags; /* client is in control of this ack */
1114 	new->tx.cookie = -EBUSY;
1115 	list_splice(&first->tx_list, &new->tx_list);
1116 
1117 	return &new->tx;
1118 
1119 fail:
1120 	if (!first)
1121 		return NULL;
1122 
1123 	xgene_dma_free_desc_list(chan, &first->tx_list);
1124 	return NULL;
1125 }
1126 
1127 static void xgene_dma_issue_pending(struct dma_chan *dchan)
1128 {
1129 	struct xgene_dma_chan *chan = to_dma_chan(dchan);
1130 
1131 	spin_lock_bh(&chan->lock);
1132 	xgene_chan_xfer_ld_pending(chan);
1133 	spin_unlock_bh(&chan->lock);
1134 }
1135 
1136 static enum dma_status xgene_dma_tx_status(struct dma_chan *dchan,
1137 					   dma_cookie_t cookie,
1138 					   struct dma_tx_state *txstate)
1139 {
1140 	return dma_cookie_status(dchan, cookie, txstate);
1141 }
1142 
1143 static void xgene_dma_tasklet_cb(unsigned long data)
1144 {
1145 	struct xgene_dma_chan *chan = (struct xgene_dma_chan *)data;
1146 
1147 	/* Run all cleanup for descriptors which have been completed */
1148 	xgene_dma_cleanup_descriptors(chan);
1149 
1150 	/* Re-enable DMA channel IRQ */
1151 	enable_irq(chan->rx_irq);
1152 }
1153 
1154 static irqreturn_t xgene_dma_chan_ring_isr(int irq, void *id)
1155 {
1156 	struct xgene_dma_chan *chan = (struct xgene_dma_chan *)id;
1157 
1158 	BUG_ON(!chan);
1159 
1160 	/*
1161 	 * Disable DMA channel IRQ until we process completed
1162 	 * descriptors
1163 	 */
1164 	disable_irq_nosync(chan->rx_irq);
1165 
1166 	/*
1167 	 * Schedule the tasklet to handle all cleanup of the current
1168 	 * transaction. It will start a new transaction if there is
1169 	 * one pending.
1170 	 */
1171 	tasklet_schedule(&chan->tasklet);
1172 
1173 	return IRQ_HANDLED;
1174 }
1175 
1176 static irqreturn_t xgene_dma_err_isr(int irq, void *id)
1177 {
1178 	struct xgene_dma *pdma = (struct xgene_dma *)id;
1179 	unsigned long int_mask;
1180 	u32 val, i;
1181 
1182 	val = ioread32(pdma->csr_dma + XGENE_DMA_INT);
1183 
1184 	/* Clear DMA interrupts */
1185 	iowrite32(val, pdma->csr_dma + XGENE_DMA_INT);
1186 
1187 	/* Print DMA error info */
1188 	int_mask = val >> XGENE_DMA_INT_MASK_SHIFT;
1189 	for_each_set_bit(i, &int_mask, ARRAY_SIZE(xgene_dma_err))
1190 		dev_err(pdma->dev,
1191 			"Interrupt status 0x%08X %s\n", val, xgene_dma_err[i]);
1192 
1193 	return IRQ_HANDLED;
1194 }
1195 
1196 static void xgene_dma_wr_ring_state(struct xgene_dma_ring *ring)
1197 {
1198 	int i;
1199 
1200 	iowrite32(ring->num, ring->pdma->csr_ring + XGENE_DMA_RING_STATE);
1201 
1202 	for (i = 0; i < XGENE_DMA_RING_NUM_CONFIG; i++)
1203 		iowrite32(ring->state[i], ring->pdma->csr_ring +
1204 			  XGENE_DMA_RING_STATE_WR_BASE + (i * 4));
1205 }
1206 
1207 static void xgene_dma_clr_ring_state(struct xgene_dma_ring *ring)
1208 {
1209 	memset(ring->state, 0, sizeof(u32) * XGENE_DMA_RING_NUM_CONFIG);
1210 	xgene_dma_wr_ring_state(ring);
1211 }
1212 
1213 static void xgene_dma_setup_ring(struct xgene_dma_ring *ring)
1214 {
1215 	void *ring_cfg = ring->state;
1216 	u64 addr = ring->desc_paddr;
1217 	u32 i, val;
1218 
1219 	ring->slots = ring->size / XGENE_DMA_RING_WQ_DESC_SIZE;
1220 
1221 	/* Clear DMA ring state */
1222 	xgene_dma_clr_ring_state(ring);
1223 
1224 	/* Set DMA ring type */
1225 	XGENE_DMA_RING_TYPE_SET(ring_cfg, XGENE_DMA_RING_TYPE_REGULAR);
1226 
1227 	if (ring->owner == XGENE_DMA_RING_OWNER_DMA) {
1228 		/* Set recombination buffer and timeout */
1229 		XGENE_DMA_RING_RECOMBBUF_SET(ring_cfg);
1230 		XGENE_DMA_RING_RECOMTIMEOUTL_SET(ring_cfg);
1231 		XGENE_DMA_RING_RECOMTIMEOUTH_SET(ring_cfg);
1232 	}
1233 
1234 	/* Initialize DMA ring state */
1235 	XGENE_DMA_RING_SELTHRSH_SET(ring_cfg);
1236 	XGENE_DMA_RING_ACCEPTLERR_SET(ring_cfg);
1237 	XGENE_DMA_RING_COHERENT_SET(ring_cfg);
1238 	XGENE_DMA_RING_ADDRL_SET(ring_cfg, addr);
1239 	XGENE_DMA_RING_ADDRH_SET(ring_cfg, addr);
1240 	XGENE_DMA_RING_SIZE_SET(ring_cfg, ring->cfgsize);
1241 
1242 	/* Write DMA ring configurations */
1243 	xgene_dma_wr_ring_state(ring);
1244 
1245 	/* Set DMA ring id */
1246 	iowrite32(XGENE_DMA_RING_ID_SETUP(ring->id),
1247 		  ring->pdma->csr_ring + XGENE_DMA_RING_ID);
1248 
1249 	/* Set DMA ring buffer */
1250 	iowrite32(XGENE_DMA_RING_ID_BUF_SETUP(ring->num),
1251 		  ring->pdma->csr_ring + XGENE_DMA_RING_ID_BUF);
1252 
1253 	if (ring->owner != XGENE_DMA_RING_OWNER_CPU)
1254 		return;
1255 
1256 	/* Set empty signature to DMA Rx ring descriptors */
1257 	for (i = 0; i < ring->slots; i++) {
1258 		struct xgene_dma_desc_hw *desc;
1259 
1260 		desc = &ring->desc_hw[i];
1261 		desc->m0 = cpu_to_le64(XGENE_DMA_DESC_EMPTY_SIGNATURE);
1262 	}
1263 
1264 	/* Enable DMA Rx ring interrupt */
1265 	val = ioread32(ring->pdma->csr_ring + XGENE_DMA_RING_NE_INT_MODE);
1266 	XGENE_DMA_RING_NE_INT_MODE_SET(val, ring->buf_num);
1267 	iowrite32(val, ring->pdma->csr_ring + XGENE_DMA_RING_NE_INT_MODE);
1268 }
1269 
1270 static void xgene_dma_clear_ring(struct xgene_dma_ring *ring)
1271 {
1272 	u32 ring_id, val;
1273 
1274 	if (ring->owner == XGENE_DMA_RING_OWNER_CPU) {
1275 		/* Disable DMA Rx ring interrupt */
1276 		val = ioread32(ring->pdma->csr_ring +
1277 			       XGENE_DMA_RING_NE_INT_MODE);
1278 		XGENE_DMA_RING_NE_INT_MODE_RESET(val, ring->buf_num);
1279 		iowrite32(val, ring->pdma->csr_ring +
1280 			  XGENE_DMA_RING_NE_INT_MODE);
1281 	}
1282 
1283 	/* Clear DMA ring state */
1284 	ring_id = XGENE_DMA_RING_ID_SETUP(ring->id);
1285 	iowrite32(ring_id, ring->pdma->csr_ring + XGENE_DMA_RING_ID);
1286 
1287 	iowrite32(0, ring->pdma->csr_ring + XGENE_DMA_RING_ID_BUF);
1288 	xgene_dma_clr_ring_state(ring);
1289 }
1290 
1291 static void xgene_dma_set_ring_cmd(struct xgene_dma_ring *ring)
1292 {
1293 	ring->cmd_base = ring->pdma->csr_ring_cmd +
1294 				XGENE_DMA_RING_CMD_BASE_OFFSET((ring->num -
1295 							  XGENE_DMA_RING_NUM));
1296 
1297 	ring->cmd = ring->cmd_base + XGENE_DMA_RING_CMD_OFFSET;
1298 }
1299 
1300 static int xgene_dma_get_ring_size(struct xgene_dma_chan *chan,
1301 				   enum xgene_dma_ring_cfgsize cfgsize)
1302 {
1303 	int size;
1304 
1305 	switch (cfgsize) {
1306 	case XGENE_DMA_RING_CFG_SIZE_512B:
1307 		size = 0x200;
1308 		break;
1309 	case XGENE_DMA_RING_CFG_SIZE_2KB:
1310 		size = 0x800;
1311 		break;
1312 	case XGENE_DMA_RING_CFG_SIZE_16KB:
1313 		size = 0x4000;
1314 		break;
1315 	case XGENE_DMA_RING_CFG_SIZE_64KB:
1316 		size = 0x10000;
1317 		break;
1318 	case XGENE_DMA_RING_CFG_SIZE_512KB:
1319 		size = 0x80000;
1320 		break;
1321 	default:
1322 		chan_err(chan, "Unsupported cfg ring size %d\n", cfgsize);
1323 		return -EINVAL;
1324 	}
1325 
1326 	return size;
1327 }
1328 
1329 static void xgene_dma_delete_ring_one(struct xgene_dma_ring *ring)
1330 {
1331 	/* Clear DMA ring configurations */
1332 	xgene_dma_clear_ring(ring);
1333 
1334 	/* De-allocate DMA ring descriptor */
1335 	if (ring->desc_vaddr) {
1336 		dma_free_coherent(ring->pdma->dev, ring->size,
1337 				  ring->desc_vaddr, ring->desc_paddr);
1338 		ring->desc_vaddr = NULL;
1339 	}
1340 }
1341 
1342 static void xgene_dma_delete_chan_rings(struct xgene_dma_chan *chan)
1343 {
1344 	xgene_dma_delete_ring_one(&chan->rx_ring);
1345 	xgene_dma_delete_ring_one(&chan->tx_ring);
1346 }
1347 
1348 static int xgene_dma_create_ring_one(struct xgene_dma_chan *chan,
1349 				     struct xgene_dma_ring *ring,
1350 				     enum xgene_dma_ring_cfgsize cfgsize)
1351 {
1352 	int ret;
1353 
1354 	/* Setup DMA ring descriptor variables */
1355 	ring->pdma = chan->pdma;
1356 	ring->cfgsize = cfgsize;
1357 	ring->num = chan->pdma->ring_num++;
1358 	ring->id = XGENE_DMA_RING_ID_GET(ring->owner, ring->buf_num);
1359 
1360 	ret = xgene_dma_get_ring_size(chan, cfgsize);
1361 	if (ret <= 0)
1362 		return ret;
1363 	ring->size = ret;
1364 
1365 	/* Allocate memory for DMA ring descriptor */
1366 	ring->desc_vaddr = dma_zalloc_coherent(chan->dev, ring->size,
1367 					       &ring->desc_paddr, GFP_KERNEL);
1368 	if (!ring->desc_vaddr) {
1369 		chan_err(chan, "Failed to allocate ring desc\n");
1370 		return -ENOMEM;
1371 	}
1372 
1373 	/* Configure and enable DMA ring */
1374 	xgene_dma_set_ring_cmd(ring);
1375 	xgene_dma_setup_ring(ring);
1376 
1377 	return 0;
1378 }
1379 
1380 static int xgene_dma_create_chan_rings(struct xgene_dma_chan *chan)
1381 {
1382 	struct xgene_dma_ring *rx_ring = &chan->rx_ring;
1383 	struct xgene_dma_ring *tx_ring = &chan->tx_ring;
1384 	int ret;
1385 
1386 	/* Create DMA Rx ring descriptor */
1387 	rx_ring->owner = XGENE_DMA_RING_OWNER_CPU;
1388 	rx_ring->buf_num = XGENE_DMA_CPU_BUFNUM + chan->id;
1389 
1390 	ret = xgene_dma_create_ring_one(chan, rx_ring,
1391 					XGENE_DMA_RING_CFG_SIZE_64KB);
1392 	if (ret)
1393 		return ret;
1394 
1395 	chan_dbg(chan, "Rx ring id 0x%X num %d desc 0x%p\n",
1396 		 rx_ring->id, rx_ring->num, rx_ring->desc_vaddr);
1397 
1398 	/* Create DMA Tx ring descriptor */
1399 	tx_ring->owner = XGENE_DMA_RING_OWNER_DMA;
1400 	tx_ring->buf_num = XGENE_DMA_BUFNUM + chan->id;
1401 
1402 	ret = xgene_dma_create_ring_one(chan, tx_ring,
1403 					XGENE_DMA_RING_CFG_SIZE_64KB);
1404 	if (ret) {
1405 		xgene_dma_delete_ring_one(rx_ring);
1406 		return ret;
1407 	}
1408 
1409 	tx_ring->dst_ring_num = XGENE_DMA_RING_DST_ID(rx_ring->num);
1410 
1411 	chan_dbg(chan,
1412 		 "Tx ring id 0x%X num %d desc 0x%p\n",
1413 		 tx_ring->id, tx_ring->num, tx_ring->desc_vaddr);
1414 
1415 	/* Set the max outstanding request possible to this channel */
1416 	chan->max_outstanding = tx_ring->slots;
1417 
1418 	return ret;
1419 }
1420 
1421 static int xgene_dma_init_rings(struct xgene_dma *pdma)
1422 {
1423 	int ret, i, j;
1424 
1425 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1426 		ret = xgene_dma_create_chan_rings(&pdma->chan[i]);
1427 		if (ret) {
1428 			for (j = 0; j < i; j++)
1429 				xgene_dma_delete_chan_rings(&pdma->chan[j]);
1430 			return ret;
1431 		}
1432 	}
1433 
1434 	return ret;
1435 }
1436 
1437 static void xgene_dma_enable(struct xgene_dma *pdma)
1438 {
1439 	u32 val;
1440 
1441 	/* Configure and enable DMA engine */
1442 	val = ioread32(pdma->csr_dma + XGENE_DMA_GCR);
1443 	XGENE_DMA_CH_SETUP(val);
1444 	XGENE_DMA_ENABLE(val);
1445 	iowrite32(val, pdma->csr_dma + XGENE_DMA_GCR);
1446 }
1447 
1448 static void xgene_dma_disable(struct xgene_dma *pdma)
1449 {
1450 	u32 val;
1451 
1452 	val = ioread32(pdma->csr_dma + XGENE_DMA_GCR);
1453 	XGENE_DMA_DISABLE(val);
1454 	iowrite32(val, pdma->csr_dma + XGENE_DMA_GCR);
1455 }
1456 
1457 static void xgene_dma_mask_interrupts(struct xgene_dma *pdma)
1458 {
1459 	/*
1460 	 * Mask DMA ring overflow, underflow and
1461 	 * AXI write/read error interrupts
1462 	 */
1463 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1464 		  pdma->csr_dma + XGENE_DMA_RING_INT0_MASK);
1465 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1466 		  pdma->csr_dma + XGENE_DMA_RING_INT1_MASK);
1467 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1468 		  pdma->csr_dma + XGENE_DMA_RING_INT2_MASK);
1469 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1470 		  pdma->csr_dma + XGENE_DMA_RING_INT3_MASK);
1471 	iowrite32(XGENE_DMA_INT_ALL_MASK,
1472 		  pdma->csr_dma + XGENE_DMA_RING_INT4_MASK);
1473 
1474 	/* Mask DMA error interrupts */
1475 	iowrite32(XGENE_DMA_INT_ALL_MASK, pdma->csr_dma + XGENE_DMA_INT_MASK);
1476 }
1477 
1478 static void xgene_dma_unmask_interrupts(struct xgene_dma *pdma)
1479 {
1480 	/*
1481 	 * Unmask DMA ring overflow, underflow and
1482 	 * AXI write/read error interrupts
1483 	 */
1484 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1485 		  pdma->csr_dma + XGENE_DMA_RING_INT0_MASK);
1486 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1487 		  pdma->csr_dma + XGENE_DMA_RING_INT1_MASK);
1488 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1489 		  pdma->csr_dma + XGENE_DMA_RING_INT2_MASK);
1490 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1491 		  pdma->csr_dma + XGENE_DMA_RING_INT3_MASK);
1492 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1493 		  pdma->csr_dma + XGENE_DMA_RING_INT4_MASK);
1494 
1495 	/* Unmask DMA error interrupts */
1496 	iowrite32(XGENE_DMA_INT_ALL_UNMASK,
1497 		  pdma->csr_dma + XGENE_DMA_INT_MASK);
1498 }
1499 
1500 static void xgene_dma_init_hw(struct xgene_dma *pdma)
1501 {
1502 	u32 val;
1503 
1504 	/* Associate DMA ring to corresponding ring HW */
1505 	iowrite32(XGENE_DMA_ASSOC_RING_MNGR1,
1506 		  pdma->csr_dma + XGENE_DMA_CFG_RING_WQ_ASSOC);
1507 
1508 	/* Configure RAID6 polynomial control setting */
1509 	if (is_pq_enabled(pdma))
1510 		iowrite32(XGENE_DMA_RAID6_MULTI_CTRL(0x1D),
1511 			  pdma->csr_dma + XGENE_DMA_RAID6_CONT);
1512 	else
1513 		dev_info(pdma->dev, "PQ is disabled in HW\n");
1514 
1515 	xgene_dma_enable(pdma);
1516 	xgene_dma_unmask_interrupts(pdma);
1517 
1518 	/* Get DMA id and version info */
1519 	val = ioread32(pdma->csr_dma + XGENE_DMA_IPBRR);
1520 
1521 	/* DMA device info */
1522 	dev_info(pdma->dev,
1523 		 "X-Gene DMA v%d.%02d.%02d driver registered %d channels",
1524 		 XGENE_DMA_REV_NO_RD(val), XGENE_DMA_BUS_ID_RD(val),
1525 		 XGENE_DMA_DEV_ID_RD(val), XGENE_DMA_MAX_CHANNEL);
1526 }
1527 
1528 static int xgene_dma_init_ring_mngr(struct xgene_dma *pdma)
1529 {
1530 	if (ioread32(pdma->csr_ring + XGENE_DMA_RING_CLKEN) &&
1531 	    (!ioread32(pdma->csr_ring + XGENE_DMA_RING_SRST)))
1532 		return 0;
1533 
1534 	iowrite32(0x3, pdma->csr_ring + XGENE_DMA_RING_CLKEN);
1535 	iowrite32(0x0, pdma->csr_ring + XGENE_DMA_RING_SRST);
1536 
1537 	/* Bring up memory */
1538 	iowrite32(0x0, pdma->csr_ring + XGENE_DMA_RING_MEM_RAM_SHUTDOWN);
1539 
1540 	/* Force a barrier */
1541 	ioread32(pdma->csr_ring + XGENE_DMA_RING_MEM_RAM_SHUTDOWN);
1542 
1543 	/* reset may take up to 1ms */
1544 	usleep_range(1000, 1100);
1545 
1546 	if (ioread32(pdma->csr_ring + XGENE_DMA_RING_BLK_MEM_RDY)
1547 		!= XGENE_DMA_RING_BLK_MEM_RDY_VAL) {
1548 		dev_err(pdma->dev,
1549 			"Failed to release ring mngr memory from shutdown\n");
1550 		return -ENODEV;
1551 	}
1552 
1553 	/* program threshold set 1 and all hysteresis */
1554 	iowrite32(XGENE_DMA_RING_THRESLD0_SET1_VAL,
1555 		  pdma->csr_ring + XGENE_DMA_RING_THRESLD0_SET1);
1556 	iowrite32(XGENE_DMA_RING_THRESLD1_SET1_VAL,
1557 		  pdma->csr_ring + XGENE_DMA_RING_THRESLD1_SET1);
1558 	iowrite32(XGENE_DMA_RING_HYSTERESIS_VAL,
1559 		  pdma->csr_ring + XGENE_DMA_RING_HYSTERESIS);
1560 
1561 	/* Enable QPcore and assign error queue */
1562 	iowrite32(XGENE_DMA_RING_ENABLE,
1563 		  pdma->csr_ring + XGENE_DMA_RING_CONFIG);
1564 
1565 	return 0;
1566 }
1567 
1568 static int xgene_dma_init_mem(struct xgene_dma *pdma)
1569 {
1570 	int ret;
1571 
1572 	ret = xgene_dma_init_ring_mngr(pdma);
1573 	if (ret)
1574 		return ret;
1575 
1576 	/* Bring up memory */
1577 	iowrite32(0x0, pdma->csr_dma + XGENE_DMA_MEM_RAM_SHUTDOWN);
1578 
1579 	/* Force a barrier */
1580 	ioread32(pdma->csr_dma + XGENE_DMA_MEM_RAM_SHUTDOWN);
1581 
1582 	/* reset may take up to 1ms */
1583 	usleep_range(1000, 1100);
1584 
1585 	if (ioread32(pdma->csr_dma + XGENE_DMA_BLK_MEM_RDY)
1586 		!= XGENE_DMA_BLK_MEM_RDY_VAL) {
1587 		dev_err(pdma->dev,
1588 			"Failed to release DMA memory from shutdown\n");
1589 		return -ENODEV;
1590 	}
1591 
1592 	return 0;
1593 }
1594 
1595 static int xgene_dma_request_irqs(struct xgene_dma *pdma)
1596 {
1597 	struct xgene_dma_chan *chan;
1598 	int ret, i, j;
1599 
1600 	/* Register DMA error irq */
1601 	ret = devm_request_irq(pdma->dev, pdma->err_irq, xgene_dma_err_isr,
1602 			       0, "dma_error", pdma);
1603 	if (ret) {
1604 		dev_err(pdma->dev,
1605 			"Failed to register error IRQ %d\n", pdma->err_irq);
1606 		return ret;
1607 	}
1608 
1609 	/* Register DMA channel rx irq */
1610 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1611 		chan = &pdma->chan[i];
1612 		irq_set_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1613 		ret = devm_request_irq(chan->dev, chan->rx_irq,
1614 				       xgene_dma_chan_ring_isr,
1615 				       0, chan->name, chan);
1616 		if (ret) {
1617 			chan_err(chan, "Failed to register Rx IRQ %d\n",
1618 				 chan->rx_irq);
1619 			devm_free_irq(pdma->dev, pdma->err_irq, pdma);
1620 
1621 			for (j = 0; j < i; j++) {
1622 				chan = &pdma->chan[i];
1623 				irq_clear_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1624 				devm_free_irq(chan->dev, chan->rx_irq, chan);
1625 			}
1626 
1627 			return ret;
1628 		}
1629 	}
1630 
1631 	return 0;
1632 }
1633 
1634 static void xgene_dma_free_irqs(struct xgene_dma *pdma)
1635 {
1636 	struct xgene_dma_chan *chan;
1637 	int i;
1638 
1639 	/* Free DMA device error irq */
1640 	devm_free_irq(pdma->dev, pdma->err_irq, pdma);
1641 
1642 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1643 		chan = &pdma->chan[i];
1644 		irq_clear_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
1645 		devm_free_irq(chan->dev, chan->rx_irq, chan);
1646 	}
1647 }
1648 
1649 static void xgene_dma_set_caps(struct xgene_dma_chan *chan,
1650 			       struct dma_device *dma_dev)
1651 {
1652 	/* Initialize DMA device capability mask */
1653 	dma_cap_zero(dma_dev->cap_mask);
1654 
1655 	/* Set DMA device capability */
1656 	dma_cap_set(DMA_SG, dma_dev->cap_mask);
1657 
1658 	/* Basically here, the X-Gene SoC DMA engine channel 0 supports XOR
1659 	 * and channel 1 supports XOR, PQ both. First thing here is we have
1660 	 * mechanism in hw to enable/disable PQ/XOR supports on channel 1,
1661 	 * we can make sure this by reading SoC Efuse register.
1662 	 * Second thing, we have hw errata that if we run channel 0 and
1663 	 * channel 1 simultaneously with executing XOR and PQ request,
1664 	 * suddenly DMA engine hangs, So here we enable XOR on channel 0 only
1665 	 * if XOR and PQ supports on channel 1 is disabled.
1666 	 */
1667 	if ((chan->id == XGENE_DMA_PQ_CHANNEL) &&
1668 	    is_pq_enabled(chan->pdma)) {
1669 		dma_cap_set(DMA_PQ, dma_dev->cap_mask);
1670 		dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1671 	} else if ((chan->id == XGENE_DMA_XOR_CHANNEL) &&
1672 		   !is_pq_enabled(chan->pdma)) {
1673 		dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1674 	}
1675 
1676 	/* Set base and prep routines */
1677 	dma_dev->dev = chan->dev;
1678 	dma_dev->device_alloc_chan_resources = xgene_dma_alloc_chan_resources;
1679 	dma_dev->device_free_chan_resources = xgene_dma_free_chan_resources;
1680 	dma_dev->device_issue_pending = xgene_dma_issue_pending;
1681 	dma_dev->device_tx_status = xgene_dma_tx_status;
1682 	dma_dev->device_prep_dma_sg = xgene_dma_prep_sg;
1683 
1684 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1685 		dma_dev->device_prep_dma_xor = xgene_dma_prep_xor;
1686 		dma_dev->max_xor = XGENE_DMA_MAX_XOR_SRC;
1687 		dma_dev->xor_align = DMAENGINE_ALIGN_64_BYTES;
1688 	}
1689 
1690 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
1691 		dma_dev->device_prep_dma_pq = xgene_dma_prep_pq;
1692 		dma_dev->max_pq = XGENE_DMA_MAX_XOR_SRC;
1693 		dma_dev->pq_align = DMAENGINE_ALIGN_64_BYTES;
1694 	}
1695 }
1696 
1697 static int xgene_dma_async_register(struct xgene_dma *pdma, int id)
1698 {
1699 	struct xgene_dma_chan *chan = &pdma->chan[id];
1700 	struct dma_device *dma_dev = &pdma->dma_dev[id];
1701 	int ret;
1702 
1703 	chan->dma_chan.device = dma_dev;
1704 
1705 	spin_lock_init(&chan->lock);
1706 	INIT_LIST_HEAD(&chan->ld_pending);
1707 	INIT_LIST_HEAD(&chan->ld_running);
1708 	INIT_LIST_HEAD(&chan->ld_completed);
1709 	tasklet_init(&chan->tasklet, xgene_dma_tasklet_cb,
1710 		     (unsigned long)chan);
1711 
1712 	chan->pending = 0;
1713 	chan->desc_pool = NULL;
1714 	dma_cookie_init(&chan->dma_chan);
1715 
1716 	/* Setup dma device capabilities and prep routines */
1717 	xgene_dma_set_caps(chan, dma_dev);
1718 
1719 	/* Initialize DMA device list head */
1720 	INIT_LIST_HEAD(&dma_dev->channels);
1721 	list_add_tail(&chan->dma_chan.device_node, &dma_dev->channels);
1722 
1723 	/* Register with Linux async DMA framework*/
1724 	ret = dma_async_device_register(dma_dev);
1725 	if (ret) {
1726 		chan_err(chan, "Failed to register async device %d", ret);
1727 		tasklet_kill(&chan->tasklet);
1728 
1729 		return ret;
1730 	}
1731 
1732 	/* DMA capability info */
1733 	dev_info(pdma->dev,
1734 		 "%s: CAPABILITY ( %s%s%s)\n", dma_chan_name(&chan->dma_chan),
1735 		 dma_has_cap(DMA_SG, dma_dev->cap_mask) ? "SGCPY " : "",
1736 		 dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "XOR " : "",
1737 		 dma_has_cap(DMA_PQ, dma_dev->cap_mask) ? "PQ " : "");
1738 
1739 	return 0;
1740 }
1741 
1742 static int xgene_dma_init_async(struct xgene_dma *pdma)
1743 {
1744 	int ret, i, j;
1745 
1746 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL ; i++) {
1747 		ret = xgene_dma_async_register(pdma, i);
1748 		if (ret) {
1749 			for (j = 0; j < i; j++) {
1750 				dma_async_device_unregister(&pdma->dma_dev[j]);
1751 				tasklet_kill(&pdma->chan[j].tasklet);
1752 			}
1753 
1754 			return ret;
1755 		}
1756 	}
1757 
1758 	return ret;
1759 }
1760 
1761 static void xgene_dma_async_unregister(struct xgene_dma *pdma)
1762 {
1763 	int i;
1764 
1765 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++)
1766 		dma_async_device_unregister(&pdma->dma_dev[i]);
1767 }
1768 
1769 static void xgene_dma_init_channels(struct xgene_dma *pdma)
1770 {
1771 	struct xgene_dma_chan *chan;
1772 	int i;
1773 
1774 	pdma->ring_num = XGENE_DMA_RING_NUM;
1775 
1776 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1777 		chan = &pdma->chan[i];
1778 		chan->dev = pdma->dev;
1779 		chan->pdma = pdma;
1780 		chan->id = i;
1781 		snprintf(chan->name, sizeof(chan->name), "dmachan%d", chan->id);
1782 	}
1783 }
1784 
1785 static int xgene_dma_get_resources(struct platform_device *pdev,
1786 				   struct xgene_dma *pdma)
1787 {
1788 	struct resource *res;
1789 	int irq, i;
1790 
1791 	/* Get DMA csr region */
1792 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1793 	if (!res) {
1794 		dev_err(&pdev->dev, "Failed to get csr region\n");
1795 		return -ENXIO;
1796 	}
1797 
1798 	pdma->csr_dma = devm_ioremap(&pdev->dev, res->start,
1799 				     resource_size(res));
1800 	if (!pdma->csr_dma) {
1801 		dev_err(&pdev->dev, "Failed to ioremap csr region");
1802 		return -ENOMEM;
1803 	}
1804 
1805 	/* Get DMA ring csr region */
1806 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1807 	if (!res) {
1808 		dev_err(&pdev->dev, "Failed to get ring csr region\n");
1809 		return -ENXIO;
1810 	}
1811 
1812 	pdma->csr_ring =  devm_ioremap(&pdev->dev, res->start,
1813 				       resource_size(res));
1814 	if (!pdma->csr_ring) {
1815 		dev_err(&pdev->dev, "Failed to ioremap ring csr region");
1816 		return -ENOMEM;
1817 	}
1818 
1819 	/* Get DMA ring cmd csr region */
1820 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
1821 	if (!res) {
1822 		dev_err(&pdev->dev, "Failed to get ring cmd csr region\n");
1823 		return -ENXIO;
1824 	}
1825 
1826 	pdma->csr_ring_cmd = devm_ioremap(&pdev->dev, res->start,
1827 					  resource_size(res));
1828 	if (!pdma->csr_ring_cmd) {
1829 		dev_err(&pdev->dev, "Failed to ioremap ring cmd csr region");
1830 		return -ENOMEM;
1831 	}
1832 
1833 	pdma->csr_ring_cmd += XGENE_DMA_RING_CMD_SM_OFFSET;
1834 
1835 	/* Get efuse csr region */
1836 	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
1837 	if (!res) {
1838 		dev_err(&pdev->dev, "Failed to get efuse csr region\n");
1839 		return -ENXIO;
1840 	}
1841 
1842 	pdma->csr_efuse = devm_ioremap(&pdev->dev, res->start,
1843 				       resource_size(res));
1844 	if (!pdma->csr_efuse) {
1845 		dev_err(&pdev->dev, "Failed to ioremap efuse csr region");
1846 		return -ENOMEM;
1847 	}
1848 
1849 	/* Get DMA error interrupt */
1850 	irq = platform_get_irq(pdev, 0);
1851 	if (irq <= 0) {
1852 		dev_err(&pdev->dev, "Failed to get Error IRQ\n");
1853 		return -ENXIO;
1854 	}
1855 
1856 	pdma->err_irq = irq;
1857 
1858 	/* Get DMA Rx ring descriptor interrupts for all DMA channels */
1859 	for (i = 1; i <= XGENE_DMA_MAX_CHANNEL; i++) {
1860 		irq = platform_get_irq(pdev, i);
1861 		if (irq <= 0) {
1862 			dev_err(&pdev->dev, "Failed to get Rx IRQ\n");
1863 			return -ENXIO;
1864 		}
1865 
1866 		pdma->chan[i - 1].rx_irq = irq;
1867 	}
1868 
1869 	return 0;
1870 }
1871 
1872 static int xgene_dma_probe(struct platform_device *pdev)
1873 {
1874 	struct xgene_dma *pdma;
1875 	int ret, i;
1876 
1877 	pdma = devm_kzalloc(&pdev->dev, sizeof(*pdma), GFP_KERNEL);
1878 	if (!pdma)
1879 		return -ENOMEM;
1880 
1881 	pdma->dev = &pdev->dev;
1882 	platform_set_drvdata(pdev, pdma);
1883 
1884 	ret = xgene_dma_get_resources(pdev, pdma);
1885 	if (ret)
1886 		return ret;
1887 
1888 	pdma->clk = devm_clk_get(&pdev->dev, NULL);
1889 	if (IS_ERR(pdma->clk) && !ACPI_COMPANION(&pdev->dev)) {
1890 		dev_err(&pdev->dev, "Failed to get clk\n");
1891 		return PTR_ERR(pdma->clk);
1892 	}
1893 
1894 	/* Enable clk before accessing registers */
1895 	if (!IS_ERR(pdma->clk)) {
1896 		ret = clk_prepare_enable(pdma->clk);
1897 		if (ret) {
1898 			dev_err(&pdev->dev, "Failed to enable clk %d\n", ret);
1899 			return ret;
1900 		}
1901 	}
1902 
1903 	/* Remove DMA RAM out of shutdown */
1904 	ret = xgene_dma_init_mem(pdma);
1905 	if (ret)
1906 		goto err_clk_enable;
1907 
1908 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(42));
1909 	if (ret) {
1910 		dev_err(&pdev->dev, "No usable DMA configuration\n");
1911 		goto err_dma_mask;
1912 	}
1913 
1914 	/* Initialize DMA channels software state */
1915 	xgene_dma_init_channels(pdma);
1916 
1917 	/* Configue DMA rings */
1918 	ret = xgene_dma_init_rings(pdma);
1919 	if (ret)
1920 		goto err_clk_enable;
1921 
1922 	ret = xgene_dma_request_irqs(pdma);
1923 	if (ret)
1924 		goto err_request_irq;
1925 
1926 	/* Configure and enable DMA engine */
1927 	xgene_dma_init_hw(pdma);
1928 
1929 	/* Register DMA device with linux async framework */
1930 	ret = xgene_dma_init_async(pdma);
1931 	if (ret)
1932 		goto err_async_init;
1933 
1934 	return 0;
1935 
1936 err_async_init:
1937 	xgene_dma_free_irqs(pdma);
1938 
1939 err_request_irq:
1940 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++)
1941 		xgene_dma_delete_chan_rings(&pdma->chan[i]);
1942 
1943 err_dma_mask:
1944 err_clk_enable:
1945 	if (!IS_ERR(pdma->clk))
1946 		clk_disable_unprepare(pdma->clk);
1947 
1948 	return ret;
1949 }
1950 
1951 static int xgene_dma_remove(struct platform_device *pdev)
1952 {
1953 	struct xgene_dma *pdma = platform_get_drvdata(pdev);
1954 	struct xgene_dma_chan *chan;
1955 	int i;
1956 
1957 	xgene_dma_async_unregister(pdma);
1958 
1959 	/* Mask interrupts and disable DMA engine */
1960 	xgene_dma_mask_interrupts(pdma);
1961 	xgene_dma_disable(pdma);
1962 	xgene_dma_free_irqs(pdma);
1963 
1964 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
1965 		chan = &pdma->chan[i];
1966 		tasklet_kill(&chan->tasklet);
1967 		xgene_dma_delete_chan_rings(chan);
1968 	}
1969 
1970 	if (!IS_ERR(pdma->clk))
1971 		clk_disable_unprepare(pdma->clk);
1972 
1973 	return 0;
1974 }
1975 
1976 #ifdef CONFIG_ACPI
1977 static const struct acpi_device_id xgene_dma_acpi_match_ptr[] = {
1978 	{"APMC0D43", 0},
1979 	{},
1980 };
1981 MODULE_DEVICE_TABLE(acpi, xgene_dma_acpi_match_ptr);
1982 #endif
1983 
1984 static const struct of_device_id xgene_dma_of_match_ptr[] = {
1985 	{.compatible = "apm,xgene-storm-dma",},
1986 	{},
1987 };
1988 MODULE_DEVICE_TABLE(of, xgene_dma_of_match_ptr);
1989 
1990 static struct platform_driver xgene_dma_driver = {
1991 	.probe = xgene_dma_probe,
1992 	.remove = xgene_dma_remove,
1993 	.driver = {
1994 		.name = "X-Gene-DMA",
1995 		.of_match_table = xgene_dma_of_match_ptr,
1996 		.acpi_match_table = ACPI_PTR(xgene_dma_acpi_match_ptr),
1997 	},
1998 };
1999 
2000 module_platform_driver(xgene_dma_driver);
2001 
2002 MODULE_DESCRIPTION("APM X-Gene SoC DMA driver");
2003 MODULE_AUTHOR("Rameshwar Prasad Sahu <rsahu@apm.com>");
2004 MODULE_AUTHOR("Loc Ho <lho@apm.com>");
2005 MODULE_LICENSE("GPL");
2006 MODULE_VERSION("1.0");
2007