xref: /openbmc/linux/drivers/dma/sprd-dma.c (revision 4bb1e4e7)
1 /*
2  * Copyright (C) 2017 Spreadtrum Communications Inc.
3  *
4  * SPDX-License-Identifier: GPL-2.0
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/dma/sprd-dma.h>
10 #include <linux/errno.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_dma.h>
18 #include <linux/of_device.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/slab.h>
21 
22 #include "virt-dma.h"
23 
24 #define SPRD_DMA_CHN_REG_OFFSET		0x1000
25 #define SPRD_DMA_CHN_REG_LENGTH		0x40
26 #define SPRD_DMA_MEMCPY_MIN_SIZE	64
27 
28 /* DMA global registers definition */
29 #define SPRD_DMA_GLB_PAUSE		0x0
30 #define SPRD_DMA_GLB_FRAG_WAIT		0x4
31 #define SPRD_DMA_GLB_REQ_PEND0_EN	0x8
32 #define SPRD_DMA_GLB_REQ_PEND1_EN	0xc
33 #define SPRD_DMA_GLB_INT_RAW_STS	0x10
34 #define SPRD_DMA_GLB_INT_MSK_STS	0x14
35 #define SPRD_DMA_GLB_REQ_STS		0x18
36 #define SPRD_DMA_GLB_CHN_EN_STS		0x1c
37 #define SPRD_DMA_GLB_DEBUG_STS		0x20
38 #define SPRD_DMA_GLB_ARB_SEL_STS	0x24
39 #define SPRD_DMA_GLB_2STAGE_GRP1	0x28
40 #define SPRD_DMA_GLB_2STAGE_GRP2	0x2c
41 #define SPRD_DMA_GLB_REQ_UID(uid)	(0x4 * ((uid) - 1))
42 #define SPRD_DMA_GLB_REQ_UID_OFFSET	0x2000
43 
44 /* DMA channel registers definition */
45 #define SPRD_DMA_CHN_PAUSE		0x0
46 #define SPRD_DMA_CHN_REQ		0x4
47 #define SPRD_DMA_CHN_CFG		0x8
48 #define SPRD_DMA_CHN_INTC		0xc
49 #define SPRD_DMA_CHN_SRC_ADDR		0x10
50 #define SPRD_DMA_CHN_DES_ADDR		0x14
51 #define SPRD_DMA_CHN_FRG_LEN		0x18
52 #define SPRD_DMA_CHN_BLK_LEN		0x1c
53 #define SPRD_DMA_CHN_TRSC_LEN		0x20
54 #define SPRD_DMA_CHN_TRSF_STEP		0x24
55 #define SPRD_DMA_CHN_WARP_PTR		0x28
56 #define SPRD_DMA_CHN_WARP_TO		0x2c
57 #define SPRD_DMA_CHN_LLIST_PTR		0x30
58 #define SPRD_DMA_CHN_FRAG_STEP		0x34
59 #define SPRD_DMA_CHN_SRC_BLK_STEP	0x38
60 #define SPRD_DMA_CHN_DES_BLK_STEP	0x3c
61 
62 /* SPRD_DMA_GLB_2STAGE_GRP register definition */
63 #define SPRD_DMA_GLB_2STAGE_EN		BIT(24)
64 #define SPRD_DMA_GLB_CHN_INT_MASK	GENMASK(23, 20)
65 #define SPRD_DMA_GLB_DEST_INT		BIT(22)
66 #define SPRD_DMA_GLB_SRC_INT		BIT(20)
67 #define SPRD_DMA_GLB_LIST_DONE_TRG	BIT(19)
68 #define SPRD_DMA_GLB_TRANS_DONE_TRG	BIT(18)
69 #define SPRD_DMA_GLB_BLOCK_DONE_TRG	BIT(17)
70 #define SPRD_DMA_GLB_FRAG_DONE_TRG	BIT(16)
71 #define SPRD_DMA_GLB_TRG_OFFSET		16
72 #define SPRD_DMA_GLB_DEST_CHN_MASK	GENMASK(13, 8)
73 #define SPRD_DMA_GLB_DEST_CHN_OFFSET	8
74 #define SPRD_DMA_GLB_SRC_CHN_MASK	GENMASK(5, 0)
75 
76 /* SPRD_DMA_CHN_INTC register definition */
77 #define SPRD_DMA_INT_MASK		GENMASK(4, 0)
78 #define SPRD_DMA_INT_CLR_OFFSET		24
79 #define SPRD_DMA_FRAG_INT_EN		BIT(0)
80 #define SPRD_DMA_BLK_INT_EN		BIT(1)
81 #define SPRD_DMA_TRANS_INT_EN		BIT(2)
82 #define SPRD_DMA_LIST_INT_EN		BIT(3)
83 #define SPRD_DMA_CFG_ERR_INT_EN		BIT(4)
84 
85 /* SPRD_DMA_CHN_CFG register definition */
86 #define SPRD_DMA_CHN_EN			BIT(0)
87 #define SPRD_DMA_LINKLIST_EN		BIT(4)
88 #define SPRD_DMA_WAIT_BDONE_OFFSET	24
89 #define SPRD_DMA_DONOT_WAIT_BDONE	1
90 
91 /* SPRD_DMA_CHN_REQ register definition */
92 #define SPRD_DMA_REQ_EN			BIT(0)
93 
94 /* SPRD_DMA_CHN_PAUSE register definition */
95 #define SPRD_DMA_PAUSE_EN		BIT(0)
96 #define SPRD_DMA_PAUSE_STS		BIT(2)
97 #define SPRD_DMA_PAUSE_CNT		0x2000
98 
99 /* DMA_CHN_WARP_* register definition */
100 #define SPRD_DMA_HIGH_ADDR_MASK		GENMASK(31, 28)
101 #define SPRD_DMA_LOW_ADDR_MASK		GENMASK(31, 0)
102 #define SPRD_DMA_WRAP_ADDR_MASK		GENMASK(27, 0)
103 #define SPRD_DMA_HIGH_ADDR_OFFSET	4
104 
105 /* SPRD_DMA_CHN_INTC register definition */
106 #define SPRD_DMA_FRAG_INT_STS		BIT(16)
107 #define SPRD_DMA_BLK_INT_STS		BIT(17)
108 #define SPRD_DMA_TRSC_INT_STS		BIT(18)
109 #define SPRD_DMA_LIST_INT_STS		BIT(19)
110 #define SPRD_DMA_CFGERR_INT_STS		BIT(20)
111 #define SPRD_DMA_CHN_INT_STS					\
112 	(SPRD_DMA_FRAG_INT_STS | SPRD_DMA_BLK_INT_STS |		\
113 	 SPRD_DMA_TRSC_INT_STS | SPRD_DMA_LIST_INT_STS |	\
114 	 SPRD_DMA_CFGERR_INT_STS)
115 
116 /* SPRD_DMA_CHN_FRG_LEN register definition */
117 #define SPRD_DMA_SRC_DATAWIDTH_OFFSET	30
118 #define SPRD_DMA_DES_DATAWIDTH_OFFSET	28
119 #define SPRD_DMA_SWT_MODE_OFFSET	26
120 #define SPRD_DMA_REQ_MODE_OFFSET	24
121 #define SPRD_DMA_REQ_MODE_MASK		GENMASK(1, 0)
122 #define SPRD_DMA_WRAP_SEL_DEST		BIT(23)
123 #define SPRD_DMA_WRAP_EN		BIT(22)
124 #define SPRD_DMA_FIX_SEL_OFFSET		21
125 #define SPRD_DMA_FIX_EN_OFFSET		20
126 #define SPRD_DMA_LLIST_END		BIT(19)
127 #define SPRD_DMA_FRG_LEN_MASK		GENMASK(16, 0)
128 
129 /* SPRD_DMA_CHN_BLK_LEN register definition */
130 #define SPRD_DMA_BLK_LEN_MASK		GENMASK(16, 0)
131 
132 /* SPRD_DMA_CHN_TRSC_LEN register definition */
133 #define SPRD_DMA_TRSC_LEN_MASK		GENMASK(27, 0)
134 
135 /* SPRD_DMA_CHN_TRSF_STEP register definition */
136 #define SPRD_DMA_DEST_TRSF_STEP_OFFSET	16
137 #define SPRD_DMA_SRC_TRSF_STEP_OFFSET	0
138 #define SPRD_DMA_TRSF_STEP_MASK		GENMASK(15, 0)
139 
140 /* SPRD DMA_SRC_BLK_STEP register definition */
141 #define SPRD_DMA_LLIST_HIGH_MASK	GENMASK(31, 28)
142 #define SPRD_DMA_LLIST_HIGH_SHIFT	28
143 
144 /* define DMA channel mode & trigger mode mask */
145 #define SPRD_DMA_CHN_MODE_MASK		GENMASK(7, 0)
146 #define SPRD_DMA_TRG_MODE_MASK		GENMASK(7, 0)
147 #define SPRD_DMA_INT_TYPE_MASK		GENMASK(7, 0)
148 
149 /* define the DMA transfer step type */
150 #define SPRD_DMA_NONE_STEP		0
151 #define SPRD_DMA_BYTE_STEP		1
152 #define SPRD_DMA_SHORT_STEP		2
153 #define SPRD_DMA_WORD_STEP		4
154 #define SPRD_DMA_DWORD_STEP		8
155 
156 #define SPRD_DMA_SOFTWARE_UID		0
157 
158 /* dma data width values */
159 enum sprd_dma_datawidth {
160 	SPRD_DMA_DATAWIDTH_1_BYTE,
161 	SPRD_DMA_DATAWIDTH_2_BYTES,
162 	SPRD_DMA_DATAWIDTH_4_BYTES,
163 	SPRD_DMA_DATAWIDTH_8_BYTES,
164 };
165 
166 /* dma channel hardware configuration */
167 struct sprd_dma_chn_hw {
168 	u32 pause;
169 	u32 req;
170 	u32 cfg;
171 	u32 intc;
172 	u32 src_addr;
173 	u32 des_addr;
174 	u32 frg_len;
175 	u32 blk_len;
176 	u32 trsc_len;
177 	u32 trsf_step;
178 	u32 wrap_ptr;
179 	u32 wrap_to;
180 	u32 llist_ptr;
181 	u32 frg_step;
182 	u32 src_blk_step;
183 	u32 des_blk_step;
184 };
185 
186 /* dma request description */
187 struct sprd_dma_desc {
188 	struct virt_dma_desc	vd;
189 	struct sprd_dma_chn_hw	chn_hw;
190 	enum dma_transfer_direction dir;
191 };
192 
193 /* dma channel description */
194 struct sprd_dma_chn {
195 	struct virt_dma_chan	vc;
196 	void __iomem		*chn_base;
197 	struct sprd_dma_linklist	linklist;
198 	struct dma_slave_config	slave_cfg;
199 	u32			chn_num;
200 	u32			dev_id;
201 	enum sprd_dma_chn_mode	chn_mode;
202 	enum sprd_dma_trg_mode	trg_mode;
203 	enum sprd_dma_int_type	int_type;
204 	struct sprd_dma_desc	*cur_desc;
205 };
206 
207 /* SPRD dma device */
208 struct sprd_dma_dev {
209 	struct dma_device	dma_dev;
210 	void __iomem		*glb_base;
211 	struct clk		*clk;
212 	struct clk		*ashb_clk;
213 	int			irq;
214 	u32			total_chns;
215 	struct sprd_dma_chn	channels[0];
216 };
217 
218 static void sprd_dma_free_desc(struct virt_dma_desc *vd);
219 static bool sprd_dma_filter_fn(struct dma_chan *chan, void *param);
220 static struct of_dma_filter_info sprd_dma_info = {
221 	.filter_fn = sprd_dma_filter_fn,
222 };
223 
224 static inline struct sprd_dma_chn *to_sprd_dma_chan(struct dma_chan *c)
225 {
226 	return container_of(c, struct sprd_dma_chn, vc.chan);
227 }
228 
229 static inline struct sprd_dma_dev *to_sprd_dma_dev(struct dma_chan *c)
230 {
231 	struct sprd_dma_chn *schan = to_sprd_dma_chan(c);
232 
233 	return container_of(schan, struct sprd_dma_dev, channels[c->chan_id]);
234 }
235 
236 static inline struct sprd_dma_desc *to_sprd_dma_desc(struct virt_dma_desc *vd)
237 {
238 	return container_of(vd, struct sprd_dma_desc, vd);
239 }
240 
241 static void sprd_dma_glb_update(struct sprd_dma_dev *sdev, u32 reg,
242 				u32 mask, u32 val)
243 {
244 	u32 orig = readl(sdev->glb_base + reg);
245 	u32 tmp;
246 
247 	tmp = (orig & ~mask) | val;
248 	writel(tmp, sdev->glb_base + reg);
249 }
250 
251 static void sprd_dma_chn_update(struct sprd_dma_chn *schan, u32 reg,
252 				u32 mask, u32 val)
253 {
254 	u32 orig = readl(schan->chn_base + reg);
255 	u32 tmp;
256 
257 	tmp = (orig & ~mask) | val;
258 	writel(tmp, schan->chn_base + reg);
259 }
260 
261 static int sprd_dma_enable(struct sprd_dma_dev *sdev)
262 {
263 	int ret;
264 
265 	ret = clk_prepare_enable(sdev->clk);
266 	if (ret)
267 		return ret;
268 
269 	/*
270 	 * The ashb_clk is optional and only for AGCP DMA controller, so we
271 	 * need add one condition to check if the ashb_clk need enable.
272 	 */
273 	if (!IS_ERR(sdev->ashb_clk))
274 		ret = clk_prepare_enable(sdev->ashb_clk);
275 
276 	return ret;
277 }
278 
279 static void sprd_dma_disable(struct sprd_dma_dev *sdev)
280 {
281 	clk_disable_unprepare(sdev->clk);
282 
283 	/*
284 	 * Need to check if we need disable the optional ashb_clk for AGCP DMA.
285 	 */
286 	if (!IS_ERR(sdev->ashb_clk))
287 		clk_disable_unprepare(sdev->ashb_clk);
288 }
289 
290 static void sprd_dma_set_uid(struct sprd_dma_chn *schan)
291 {
292 	struct sprd_dma_dev *sdev = to_sprd_dma_dev(&schan->vc.chan);
293 	u32 dev_id = schan->dev_id;
294 
295 	if (dev_id != SPRD_DMA_SOFTWARE_UID) {
296 		u32 uid_offset = SPRD_DMA_GLB_REQ_UID_OFFSET +
297 				 SPRD_DMA_GLB_REQ_UID(dev_id);
298 
299 		writel(schan->chn_num + 1, sdev->glb_base + uid_offset);
300 	}
301 }
302 
303 static void sprd_dma_unset_uid(struct sprd_dma_chn *schan)
304 {
305 	struct sprd_dma_dev *sdev = to_sprd_dma_dev(&schan->vc.chan);
306 	u32 dev_id = schan->dev_id;
307 
308 	if (dev_id != SPRD_DMA_SOFTWARE_UID) {
309 		u32 uid_offset = SPRD_DMA_GLB_REQ_UID_OFFSET +
310 				 SPRD_DMA_GLB_REQ_UID(dev_id);
311 
312 		writel(0, sdev->glb_base + uid_offset);
313 	}
314 }
315 
316 static void sprd_dma_clear_int(struct sprd_dma_chn *schan)
317 {
318 	sprd_dma_chn_update(schan, SPRD_DMA_CHN_INTC,
319 			    SPRD_DMA_INT_MASK << SPRD_DMA_INT_CLR_OFFSET,
320 			    SPRD_DMA_INT_MASK << SPRD_DMA_INT_CLR_OFFSET);
321 }
322 
323 static void sprd_dma_enable_chn(struct sprd_dma_chn *schan)
324 {
325 	sprd_dma_chn_update(schan, SPRD_DMA_CHN_CFG, SPRD_DMA_CHN_EN,
326 			    SPRD_DMA_CHN_EN);
327 }
328 
329 static void sprd_dma_disable_chn(struct sprd_dma_chn *schan)
330 {
331 	sprd_dma_chn_update(schan, SPRD_DMA_CHN_CFG, SPRD_DMA_CHN_EN, 0);
332 }
333 
334 static void sprd_dma_soft_request(struct sprd_dma_chn *schan)
335 {
336 	sprd_dma_chn_update(schan, SPRD_DMA_CHN_REQ, SPRD_DMA_REQ_EN,
337 			    SPRD_DMA_REQ_EN);
338 }
339 
340 static void sprd_dma_pause_resume(struct sprd_dma_chn *schan, bool enable)
341 {
342 	struct sprd_dma_dev *sdev = to_sprd_dma_dev(&schan->vc.chan);
343 	u32 pause, timeout = SPRD_DMA_PAUSE_CNT;
344 
345 	if (enable) {
346 		sprd_dma_chn_update(schan, SPRD_DMA_CHN_PAUSE,
347 				    SPRD_DMA_PAUSE_EN, SPRD_DMA_PAUSE_EN);
348 
349 		do {
350 			pause = readl(schan->chn_base + SPRD_DMA_CHN_PAUSE);
351 			if (pause & SPRD_DMA_PAUSE_STS)
352 				break;
353 
354 			cpu_relax();
355 		} while (--timeout > 0);
356 
357 		if (!timeout)
358 			dev_warn(sdev->dma_dev.dev,
359 				 "pause dma controller timeout\n");
360 	} else {
361 		sprd_dma_chn_update(schan, SPRD_DMA_CHN_PAUSE,
362 				    SPRD_DMA_PAUSE_EN, 0);
363 	}
364 }
365 
366 static void sprd_dma_stop_and_disable(struct sprd_dma_chn *schan)
367 {
368 	u32 cfg = readl(schan->chn_base + SPRD_DMA_CHN_CFG);
369 
370 	if (!(cfg & SPRD_DMA_CHN_EN))
371 		return;
372 
373 	sprd_dma_pause_resume(schan, true);
374 	sprd_dma_disable_chn(schan);
375 }
376 
377 static unsigned long sprd_dma_get_src_addr(struct sprd_dma_chn *schan)
378 {
379 	unsigned long addr, addr_high;
380 
381 	addr = readl(schan->chn_base + SPRD_DMA_CHN_SRC_ADDR);
382 	addr_high = readl(schan->chn_base + SPRD_DMA_CHN_WARP_PTR) &
383 		    SPRD_DMA_HIGH_ADDR_MASK;
384 
385 	return addr | (addr_high << SPRD_DMA_HIGH_ADDR_OFFSET);
386 }
387 
388 static unsigned long sprd_dma_get_dst_addr(struct sprd_dma_chn *schan)
389 {
390 	unsigned long addr, addr_high;
391 
392 	addr = readl(schan->chn_base + SPRD_DMA_CHN_DES_ADDR);
393 	addr_high = readl(schan->chn_base + SPRD_DMA_CHN_WARP_TO) &
394 		    SPRD_DMA_HIGH_ADDR_MASK;
395 
396 	return addr | (addr_high << SPRD_DMA_HIGH_ADDR_OFFSET);
397 }
398 
399 static enum sprd_dma_int_type sprd_dma_get_int_type(struct sprd_dma_chn *schan)
400 {
401 	struct sprd_dma_dev *sdev = to_sprd_dma_dev(&schan->vc.chan);
402 	u32 intc_sts = readl(schan->chn_base + SPRD_DMA_CHN_INTC) &
403 		       SPRD_DMA_CHN_INT_STS;
404 
405 	switch (intc_sts) {
406 	case SPRD_DMA_CFGERR_INT_STS:
407 		return SPRD_DMA_CFGERR_INT;
408 
409 	case SPRD_DMA_LIST_INT_STS:
410 		return SPRD_DMA_LIST_INT;
411 
412 	case SPRD_DMA_TRSC_INT_STS:
413 		return SPRD_DMA_TRANS_INT;
414 
415 	case SPRD_DMA_BLK_INT_STS:
416 		return SPRD_DMA_BLK_INT;
417 
418 	case SPRD_DMA_FRAG_INT_STS:
419 		return SPRD_DMA_FRAG_INT;
420 
421 	default:
422 		dev_warn(sdev->dma_dev.dev, "incorrect dma interrupt type\n");
423 		return SPRD_DMA_NO_INT;
424 	}
425 }
426 
427 static enum sprd_dma_req_mode sprd_dma_get_req_type(struct sprd_dma_chn *schan)
428 {
429 	u32 frag_reg = readl(schan->chn_base + SPRD_DMA_CHN_FRG_LEN);
430 
431 	return (frag_reg >> SPRD_DMA_REQ_MODE_OFFSET) & SPRD_DMA_REQ_MODE_MASK;
432 }
433 
434 static int sprd_dma_set_2stage_config(struct sprd_dma_chn *schan)
435 {
436 	struct sprd_dma_dev *sdev = to_sprd_dma_dev(&schan->vc.chan);
437 	u32 val, chn = schan->chn_num + 1;
438 
439 	switch (schan->chn_mode) {
440 	case SPRD_DMA_SRC_CHN0:
441 		val = chn & SPRD_DMA_GLB_SRC_CHN_MASK;
442 		val |= BIT(schan->trg_mode - 1) << SPRD_DMA_GLB_TRG_OFFSET;
443 		val |= SPRD_DMA_GLB_2STAGE_EN;
444 		if (schan->int_type != SPRD_DMA_NO_INT)
445 			val |= SPRD_DMA_GLB_SRC_INT;
446 
447 		sprd_dma_glb_update(sdev, SPRD_DMA_GLB_2STAGE_GRP1, val, val);
448 		break;
449 
450 	case SPRD_DMA_SRC_CHN1:
451 		val = chn & SPRD_DMA_GLB_SRC_CHN_MASK;
452 		val |= BIT(schan->trg_mode - 1) << SPRD_DMA_GLB_TRG_OFFSET;
453 		val |= SPRD_DMA_GLB_2STAGE_EN;
454 		if (schan->int_type != SPRD_DMA_NO_INT)
455 			val |= SPRD_DMA_GLB_SRC_INT;
456 
457 		sprd_dma_glb_update(sdev, SPRD_DMA_GLB_2STAGE_GRP2, val, val);
458 		break;
459 
460 	case SPRD_DMA_DST_CHN0:
461 		val = (chn << SPRD_DMA_GLB_DEST_CHN_OFFSET) &
462 			SPRD_DMA_GLB_DEST_CHN_MASK;
463 		val |= SPRD_DMA_GLB_2STAGE_EN;
464 		if (schan->int_type != SPRD_DMA_NO_INT)
465 			val |= SPRD_DMA_GLB_DEST_INT;
466 
467 		sprd_dma_glb_update(sdev, SPRD_DMA_GLB_2STAGE_GRP1, val, val);
468 		break;
469 
470 	case SPRD_DMA_DST_CHN1:
471 		val = (chn << SPRD_DMA_GLB_DEST_CHN_OFFSET) &
472 			SPRD_DMA_GLB_DEST_CHN_MASK;
473 		val |= SPRD_DMA_GLB_2STAGE_EN;
474 		if (schan->int_type != SPRD_DMA_NO_INT)
475 			val |= SPRD_DMA_GLB_DEST_INT;
476 
477 		sprd_dma_glb_update(sdev, SPRD_DMA_GLB_2STAGE_GRP2, val, val);
478 		break;
479 
480 	default:
481 		dev_err(sdev->dma_dev.dev, "invalid channel mode setting %d\n",
482 			schan->chn_mode);
483 		return -EINVAL;
484 	}
485 
486 	return 0;
487 }
488 
489 static void sprd_dma_set_chn_config(struct sprd_dma_chn *schan,
490 				    struct sprd_dma_desc *sdesc)
491 {
492 	struct sprd_dma_chn_hw *cfg = &sdesc->chn_hw;
493 
494 	writel(cfg->pause, schan->chn_base + SPRD_DMA_CHN_PAUSE);
495 	writel(cfg->cfg, schan->chn_base + SPRD_DMA_CHN_CFG);
496 	writel(cfg->intc, schan->chn_base + SPRD_DMA_CHN_INTC);
497 	writel(cfg->src_addr, schan->chn_base + SPRD_DMA_CHN_SRC_ADDR);
498 	writel(cfg->des_addr, schan->chn_base + SPRD_DMA_CHN_DES_ADDR);
499 	writel(cfg->frg_len, schan->chn_base + SPRD_DMA_CHN_FRG_LEN);
500 	writel(cfg->blk_len, schan->chn_base + SPRD_DMA_CHN_BLK_LEN);
501 	writel(cfg->trsc_len, schan->chn_base + SPRD_DMA_CHN_TRSC_LEN);
502 	writel(cfg->trsf_step, schan->chn_base + SPRD_DMA_CHN_TRSF_STEP);
503 	writel(cfg->wrap_ptr, schan->chn_base + SPRD_DMA_CHN_WARP_PTR);
504 	writel(cfg->wrap_to, schan->chn_base + SPRD_DMA_CHN_WARP_TO);
505 	writel(cfg->llist_ptr, schan->chn_base + SPRD_DMA_CHN_LLIST_PTR);
506 	writel(cfg->frg_step, schan->chn_base + SPRD_DMA_CHN_FRAG_STEP);
507 	writel(cfg->src_blk_step, schan->chn_base + SPRD_DMA_CHN_SRC_BLK_STEP);
508 	writel(cfg->des_blk_step, schan->chn_base + SPRD_DMA_CHN_DES_BLK_STEP);
509 	writel(cfg->req, schan->chn_base + SPRD_DMA_CHN_REQ);
510 }
511 
512 static void sprd_dma_start(struct sprd_dma_chn *schan)
513 {
514 	struct virt_dma_desc *vd = vchan_next_desc(&schan->vc);
515 
516 	if (!vd)
517 		return;
518 
519 	list_del(&vd->node);
520 	schan->cur_desc = to_sprd_dma_desc(vd);
521 
522 	/*
523 	 * Set 2-stage configuration if the channel starts one 2-stage
524 	 * transfer.
525 	 */
526 	if (schan->chn_mode && sprd_dma_set_2stage_config(schan))
527 		return;
528 
529 	/*
530 	 * Copy the DMA configuration from DMA descriptor to this hardware
531 	 * channel.
532 	 */
533 	sprd_dma_set_chn_config(schan, schan->cur_desc);
534 	sprd_dma_set_uid(schan);
535 	sprd_dma_enable_chn(schan);
536 
537 	if (schan->dev_id == SPRD_DMA_SOFTWARE_UID &&
538 	    schan->chn_mode != SPRD_DMA_DST_CHN0 &&
539 	    schan->chn_mode != SPRD_DMA_DST_CHN1)
540 		sprd_dma_soft_request(schan);
541 }
542 
543 static void sprd_dma_stop(struct sprd_dma_chn *schan)
544 {
545 	sprd_dma_stop_and_disable(schan);
546 	sprd_dma_unset_uid(schan);
547 	sprd_dma_clear_int(schan);
548 	schan->cur_desc = NULL;
549 }
550 
551 static bool sprd_dma_check_trans_done(struct sprd_dma_desc *sdesc,
552 				      enum sprd_dma_int_type int_type,
553 				      enum sprd_dma_req_mode req_mode)
554 {
555 	if (int_type == SPRD_DMA_NO_INT)
556 		return false;
557 
558 	if (int_type >= req_mode + 1)
559 		return true;
560 	else
561 		return false;
562 }
563 
564 static irqreturn_t dma_irq_handle(int irq, void *dev_id)
565 {
566 	struct sprd_dma_dev *sdev = (struct sprd_dma_dev *)dev_id;
567 	u32 irq_status = readl(sdev->glb_base + SPRD_DMA_GLB_INT_MSK_STS);
568 	struct sprd_dma_chn *schan;
569 	struct sprd_dma_desc *sdesc;
570 	enum sprd_dma_req_mode req_type;
571 	enum sprd_dma_int_type int_type;
572 	bool trans_done = false, cyclic = false;
573 	u32 i;
574 
575 	while (irq_status) {
576 		i = __ffs(irq_status);
577 		irq_status &= (irq_status - 1);
578 		schan = &sdev->channels[i];
579 
580 		spin_lock(&schan->vc.lock);
581 
582 		sdesc = schan->cur_desc;
583 		if (!sdesc) {
584 			spin_unlock(&schan->vc.lock);
585 			return IRQ_HANDLED;
586 		}
587 
588 		int_type = sprd_dma_get_int_type(schan);
589 		req_type = sprd_dma_get_req_type(schan);
590 		sprd_dma_clear_int(schan);
591 
592 		/* cyclic mode schedule callback */
593 		cyclic = schan->linklist.phy_addr ? true : false;
594 		if (cyclic == true) {
595 			vchan_cyclic_callback(&sdesc->vd);
596 		} else {
597 			/* Check if the dma request descriptor is done. */
598 			trans_done = sprd_dma_check_trans_done(sdesc, int_type,
599 							       req_type);
600 			if (trans_done == true) {
601 				vchan_cookie_complete(&sdesc->vd);
602 				schan->cur_desc = NULL;
603 				sprd_dma_start(schan);
604 			}
605 		}
606 		spin_unlock(&schan->vc.lock);
607 	}
608 
609 	return IRQ_HANDLED;
610 }
611 
612 static int sprd_dma_alloc_chan_resources(struct dma_chan *chan)
613 {
614 	return pm_runtime_get_sync(chan->device->dev);
615 }
616 
617 static void sprd_dma_free_chan_resources(struct dma_chan *chan)
618 {
619 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
620 	struct virt_dma_desc *cur_vd = NULL;
621 	unsigned long flags;
622 
623 	spin_lock_irqsave(&schan->vc.lock, flags);
624 	if (schan->cur_desc)
625 		cur_vd = &schan->cur_desc->vd;
626 
627 	sprd_dma_stop(schan);
628 	spin_unlock_irqrestore(&schan->vc.lock, flags);
629 
630 	if (cur_vd)
631 		sprd_dma_free_desc(cur_vd);
632 
633 	vchan_free_chan_resources(&schan->vc);
634 	pm_runtime_put(chan->device->dev);
635 }
636 
637 static enum dma_status sprd_dma_tx_status(struct dma_chan *chan,
638 					  dma_cookie_t cookie,
639 					  struct dma_tx_state *txstate)
640 {
641 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
642 	struct virt_dma_desc *vd;
643 	unsigned long flags;
644 	enum dma_status ret;
645 	u32 pos;
646 
647 	ret = dma_cookie_status(chan, cookie, txstate);
648 	if (ret == DMA_COMPLETE || !txstate)
649 		return ret;
650 
651 	spin_lock_irqsave(&schan->vc.lock, flags);
652 	vd = vchan_find_desc(&schan->vc, cookie);
653 	if (vd) {
654 		struct sprd_dma_desc *sdesc = to_sprd_dma_desc(vd);
655 		struct sprd_dma_chn_hw *hw = &sdesc->chn_hw;
656 
657 		if (hw->trsc_len > 0)
658 			pos = hw->trsc_len;
659 		else if (hw->blk_len > 0)
660 			pos = hw->blk_len;
661 		else if (hw->frg_len > 0)
662 			pos = hw->frg_len;
663 		else
664 			pos = 0;
665 	} else if (schan->cur_desc && schan->cur_desc->vd.tx.cookie == cookie) {
666 		struct sprd_dma_desc *sdesc = schan->cur_desc;
667 
668 		if (sdesc->dir == DMA_DEV_TO_MEM)
669 			pos = sprd_dma_get_dst_addr(schan);
670 		else
671 			pos = sprd_dma_get_src_addr(schan);
672 	} else {
673 		pos = 0;
674 	}
675 	spin_unlock_irqrestore(&schan->vc.lock, flags);
676 
677 	dma_set_residue(txstate, pos);
678 	return ret;
679 }
680 
681 static void sprd_dma_issue_pending(struct dma_chan *chan)
682 {
683 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
684 	unsigned long flags;
685 
686 	spin_lock_irqsave(&schan->vc.lock, flags);
687 	if (vchan_issue_pending(&schan->vc) && !schan->cur_desc)
688 		sprd_dma_start(schan);
689 	spin_unlock_irqrestore(&schan->vc.lock, flags);
690 }
691 
692 static int sprd_dma_get_datawidth(enum dma_slave_buswidth buswidth)
693 {
694 	switch (buswidth) {
695 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
696 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
697 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
698 	case DMA_SLAVE_BUSWIDTH_8_BYTES:
699 		return ffs(buswidth) - 1;
700 
701 	default:
702 		return -EINVAL;
703 	}
704 }
705 
706 static int sprd_dma_get_step(enum dma_slave_buswidth buswidth)
707 {
708 	switch (buswidth) {
709 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
710 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
711 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
712 	case DMA_SLAVE_BUSWIDTH_8_BYTES:
713 		return buswidth;
714 
715 	default:
716 		return -EINVAL;
717 	}
718 }
719 
720 static int sprd_dma_fill_desc(struct dma_chan *chan,
721 			      struct sprd_dma_chn_hw *hw,
722 			      unsigned int sglen, int sg_index,
723 			      dma_addr_t src, dma_addr_t dst, u32 len,
724 			      enum dma_transfer_direction dir,
725 			      unsigned long flags,
726 			      struct dma_slave_config *slave_cfg)
727 {
728 	struct sprd_dma_dev *sdev = to_sprd_dma_dev(chan);
729 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
730 	enum sprd_dma_chn_mode chn_mode = schan->chn_mode;
731 	u32 req_mode = (flags >> SPRD_DMA_REQ_SHIFT) & SPRD_DMA_REQ_MODE_MASK;
732 	u32 int_mode = flags & SPRD_DMA_INT_MASK;
733 	int src_datawidth, dst_datawidth, src_step, dst_step;
734 	u32 temp, fix_mode = 0, fix_en = 0;
735 	phys_addr_t llist_ptr;
736 
737 	if (dir == DMA_MEM_TO_DEV) {
738 		src_step = sprd_dma_get_step(slave_cfg->src_addr_width);
739 		if (src_step < 0) {
740 			dev_err(sdev->dma_dev.dev, "invalid source step\n");
741 			return src_step;
742 		}
743 
744 		/*
745 		 * For 2-stage transfer, destination channel step can not be 0,
746 		 * since destination device is AON IRAM.
747 		 */
748 		if (chn_mode == SPRD_DMA_DST_CHN0 ||
749 		    chn_mode == SPRD_DMA_DST_CHN1)
750 			dst_step = src_step;
751 		else
752 			dst_step = SPRD_DMA_NONE_STEP;
753 	} else {
754 		dst_step = sprd_dma_get_step(slave_cfg->dst_addr_width);
755 		if (dst_step < 0) {
756 			dev_err(sdev->dma_dev.dev, "invalid destination step\n");
757 			return dst_step;
758 		}
759 		src_step = SPRD_DMA_NONE_STEP;
760 	}
761 
762 	src_datawidth = sprd_dma_get_datawidth(slave_cfg->src_addr_width);
763 	if (src_datawidth < 0) {
764 		dev_err(sdev->dma_dev.dev, "invalid source datawidth\n");
765 		return src_datawidth;
766 	}
767 
768 	dst_datawidth = sprd_dma_get_datawidth(slave_cfg->dst_addr_width);
769 	if (dst_datawidth < 0) {
770 		dev_err(sdev->dma_dev.dev, "invalid destination datawidth\n");
771 		return dst_datawidth;
772 	}
773 
774 	if (slave_cfg->slave_id)
775 		schan->dev_id = slave_cfg->slave_id;
776 
777 	hw->cfg = SPRD_DMA_DONOT_WAIT_BDONE << SPRD_DMA_WAIT_BDONE_OFFSET;
778 
779 	/*
780 	 * wrap_ptr and wrap_to will save the high 4 bits source address and
781 	 * destination address.
782 	 */
783 	hw->wrap_ptr = (src >> SPRD_DMA_HIGH_ADDR_OFFSET) & SPRD_DMA_HIGH_ADDR_MASK;
784 	hw->wrap_to = (dst >> SPRD_DMA_HIGH_ADDR_OFFSET) & SPRD_DMA_HIGH_ADDR_MASK;
785 	hw->src_addr = src & SPRD_DMA_LOW_ADDR_MASK;
786 	hw->des_addr = dst & SPRD_DMA_LOW_ADDR_MASK;
787 
788 	/*
789 	 * If the src step and dst step both are 0 or both are not 0, that means
790 	 * we can not enable the fix mode. If one is 0 and another one is not,
791 	 * we can enable the fix mode.
792 	 */
793 	if ((src_step != 0 && dst_step != 0) || (src_step | dst_step) == 0) {
794 		fix_en = 0;
795 	} else {
796 		fix_en = 1;
797 		if (src_step)
798 			fix_mode = 1;
799 		else
800 			fix_mode = 0;
801 	}
802 
803 	hw->intc = int_mode | SPRD_DMA_CFG_ERR_INT_EN;
804 
805 	temp = src_datawidth << SPRD_DMA_SRC_DATAWIDTH_OFFSET;
806 	temp |= dst_datawidth << SPRD_DMA_DES_DATAWIDTH_OFFSET;
807 	temp |= req_mode << SPRD_DMA_REQ_MODE_OFFSET;
808 	temp |= fix_mode << SPRD_DMA_FIX_SEL_OFFSET;
809 	temp |= fix_en << SPRD_DMA_FIX_EN_OFFSET;
810 	temp |= schan->linklist.wrap_addr ?
811 		SPRD_DMA_WRAP_EN | SPRD_DMA_WRAP_SEL_DEST : 0;
812 	temp |= slave_cfg->src_maxburst & SPRD_DMA_FRG_LEN_MASK;
813 	hw->frg_len = temp;
814 
815 	hw->blk_len = slave_cfg->src_maxburst & SPRD_DMA_BLK_LEN_MASK;
816 	hw->trsc_len = len & SPRD_DMA_TRSC_LEN_MASK;
817 
818 	temp = (dst_step & SPRD_DMA_TRSF_STEP_MASK) << SPRD_DMA_DEST_TRSF_STEP_OFFSET;
819 	temp |= (src_step & SPRD_DMA_TRSF_STEP_MASK) << SPRD_DMA_SRC_TRSF_STEP_OFFSET;
820 	hw->trsf_step = temp;
821 
822 	/* link-list configuration */
823 	if (schan->linklist.phy_addr) {
824 		hw->cfg |= SPRD_DMA_LINKLIST_EN;
825 
826 		/* link-list index */
827 		temp = sglen ? (sg_index + 1) % sglen : 0;
828 
829 		/* Next link-list configuration's physical address offset */
830 		temp = temp * sizeof(*hw) + SPRD_DMA_CHN_SRC_ADDR;
831 		/*
832 		 * Set the link-list pointer point to next link-list
833 		 * configuration's physical address.
834 		 */
835 		llist_ptr = schan->linklist.phy_addr + temp;
836 		hw->llist_ptr = lower_32_bits(llist_ptr);
837 		hw->src_blk_step = (upper_32_bits(llist_ptr) << SPRD_DMA_LLIST_HIGH_SHIFT) &
838 			SPRD_DMA_LLIST_HIGH_MASK;
839 
840 		if (schan->linklist.wrap_addr) {
841 			hw->wrap_ptr |= schan->linklist.wrap_addr &
842 				SPRD_DMA_WRAP_ADDR_MASK;
843 			hw->wrap_to |= dst & SPRD_DMA_WRAP_ADDR_MASK;
844 		}
845 	} else {
846 		hw->llist_ptr = 0;
847 		hw->src_blk_step = 0;
848 	}
849 
850 	hw->frg_step = 0;
851 	hw->des_blk_step = 0;
852 	return 0;
853 }
854 
855 static int sprd_dma_fill_linklist_desc(struct dma_chan *chan,
856 				       unsigned int sglen, int sg_index,
857 				       dma_addr_t src, dma_addr_t dst, u32 len,
858 				       enum dma_transfer_direction dir,
859 				       unsigned long flags,
860 				       struct dma_slave_config *slave_cfg)
861 {
862 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
863 	struct sprd_dma_chn_hw *hw;
864 
865 	if (!schan->linklist.virt_addr)
866 		return -EINVAL;
867 
868 	hw = (struct sprd_dma_chn_hw *)(schan->linklist.virt_addr +
869 					sg_index * sizeof(*hw));
870 
871 	return sprd_dma_fill_desc(chan, hw, sglen, sg_index, src, dst, len,
872 				  dir, flags, slave_cfg);
873 }
874 
875 static struct dma_async_tx_descriptor *
876 sprd_dma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
877 			 size_t len, unsigned long flags)
878 {
879 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
880 	struct sprd_dma_desc *sdesc;
881 	struct sprd_dma_chn_hw *hw;
882 	enum sprd_dma_datawidth datawidth;
883 	u32 step, temp;
884 
885 	sdesc = kzalloc(sizeof(*sdesc), GFP_NOWAIT);
886 	if (!sdesc)
887 		return NULL;
888 
889 	hw = &sdesc->chn_hw;
890 
891 	hw->cfg = SPRD_DMA_DONOT_WAIT_BDONE << SPRD_DMA_WAIT_BDONE_OFFSET;
892 	hw->intc = SPRD_DMA_TRANS_INT | SPRD_DMA_CFG_ERR_INT_EN;
893 	hw->src_addr = src & SPRD_DMA_LOW_ADDR_MASK;
894 	hw->des_addr = dest & SPRD_DMA_LOW_ADDR_MASK;
895 	hw->wrap_ptr = (src >> SPRD_DMA_HIGH_ADDR_OFFSET) &
896 		SPRD_DMA_HIGH_ADDR_MASK;
897 	hw->wrap_to = (dest >> SPRD_DMA_HIGH_ADDR_OFFSET) &
898 		SPRD_DMA_HIGH_ADDR_MASK;
899 
900 	if (IS_ALIGNED(len, 8)) {
901 		datawidth = SPRD_DMA_DATAWIDTH_8_BYTES;
902 		step = SPRD_DMA_DWORD_STEP;
903 	} else if (IS_ALIGNED(len, 4)) {
904 		datawidth = SPRD_DMA_DATAWIDTH_4_BYTES;
905 		step = SPRD_DMA_WORD_STEP;
906 	} else if (IS_ALIGNED(len, 2)) {
907 		datawidth = SPRD_DMA_DATAWIDTH_2_BYTES;
908 		step = SPRD_DMA_SHORT_STEP;
909 	} else {
910 		datawidth = SPRD_DMA_DATAWIDTH_1_BYTE;
911 		step = SPRD_DMA_BYTE_STEP;
912 	}
913 
914 	temp = datawidth << SPRD_DMA_SRC_DATAWIDTH_OFFSET;
915 	temp |= datawidth << SPRD_DMA_DES_DATAWIDTH_OFFSET;
916 	temp |= SPRD_DMA_TRANS_REQ << SPRD_DMA_REQ_MODE_OFFSET;
917 	temp |= len & SPRD_DMA_FRG_LEN_MASK;
918 	hw->frg_len = temp;
919 
920 	hw->blk_len = len & SPRD_DMA_BLK_LEN_MASK;
921 	hw->trsc_len = len & SPRD_DMA_TRSC_LEN_MASK;
922 
923 	temp = (step & SPRD_DMA_TRSF_STEP_MASK) << SPRD_DMA_DEST_TRSF_STEP_OFFSET;
924 	temp |= (step & SPRD_DMA_TRSF_STEP_MASK) << SPRD_DMA_SRC_TRSF_STEP_OFFSET;
925 	hw->trsf_step = temp;
926 
927 	return vchan_tx_prep(&schan->vc, &sdesc->vd, flags);
928 }
929 
930 static struct dma_async_tx_descriptor *
931 sprd_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
932 		       unsigned int sglen, enum dma_transfer_direction dir,
933 		       unsigned long flags, void *context)
934 {
935 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
936 	struct dma_slave_config *slave_cfg = &schan->slave_cfg;
937 	dma_addr_t src = 0, dst = 0;
938 	dma_addr_t start_src = 0, start_dst = 0;
939 	struct sprd_dma_desc *sdesc;
940 	struct scatterlist *sg;
941 	u32 len = 0;
942 	int ret, i;
943 
944 	if (!is_slave_direction(dir))
945 		return NULL;
946 
947 	if (context) {
948 		struct sprd_dma_linklist *ll_cfg =
949 			(struct sprd_dma_linklist *)context;
950 
951 		schan->linklist.phy_addr = ll_cfg->phy_addr;
952 		schan->linklist.virt_addr = ll_cfg->virt_addr;
953 		schan->linklist.wrap_addr = ll_cfg->wrap_addr;
954 	} else {
955 		schan->linklist.phy_addr = 0;
956 		schan->linklist.virt_addr = 0;
957 		schan->linklist.wrap_addr = 0;
958 	}
959 
960 	/*
961 	 * Set channel mode, interrupt mode and trigger mode for 2-stage
962 	 * transfer.
963 	 */
964 	schan->chn_mode =
965 		(flags >> SPRD_DMA_CHN_MODE_SHIFT) & SPRD_DMA_CHN_MODE_MASK;
966 	schan->trg_mode =
967 		(flags >> SPRD_DMA_TRG_MODE_SHIFT) & SPRD_DMA_TRG_MODE_MASK;
968 	schan->int_type = flags & SPRD_DMA_INT_TYPE_MASK;
969 
970 	sdesc = kzalloc(sizeof(*sdesc), GFP_NOWAIT);
971 	if (!sdesc)
972 		return NULL;
973 
974 	sdesc->dir = dir;
975 
976 	for_each_sg(sgl, sg, sglen, i) {
977 		len = sg_dma_len(sg);
978 
979 		if (dir == DMA_MEM_TO_DEV) {
980 			src = sg_dma_address(sg);
981 			dst = slave_cfg->dst_addr;
982 		} else {
983 			src = slave_cfg->src_addr;
984 			dst = sg_dma_address(sg);
985 		}
986 
987 		if (!i) {
988 			start_src = src;
989 			start_dst = dst;
990 		}
991 
992 		/*
993 		 * The link-list mode needs at least 2 link-list
994 		 * configurations. If there is only one sg, it doesn't
995 		 * need to fill the link-list configuration.
996 		 */
997 		if (sglen < 2)
998 			break;
999 
1000 		ret = sprd_dma_fill_linklist_desc(chan, sglen, i, src, dst, len,
1001 						  dir, flags, slave_cfg);
1002 		if (ret) {
1003 			kfree(sdesc);
1004 			return NULL;
1005 		}
1006 	}
1007 
1008 	ret = sprd_dma_fill_desc(chan, &sdesc->chn_hw, 0, 0, start_src,
1009 				 start_dst, len, dir, flags, slave_cfg);
1010 	if (ret) {
1011 		kfree(sdesc);
1012 		return NULL;
1013 	}
1014 
1015 	return vchan_tx_prep(&schan->vc, &sdesc->vd, flags);
1016 }
1017 
1018 static int sprd_dma_slave_config(struct dma_chan *chan,
1019 				 struct dma_slave_config *config)
1020 {
1021 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
1022 	struct dma_slave_config *slave_cfg = &schan->slave_cfg;
1023 
1024 	memcpy(slave_cfg, config, sizeof(*config));
1025 	return 0;
1026 }
1027 
1028 static int sprd_dma_pause(struct dma_chan *chan)
1029 {
1030 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
1031 	unsigned long flags;
1032 
1033 	spin_lock_irqsave(&schan->vc.lock, flags);
1034 	sprd_dma_pause_resume(schan, true);
1035 	spin_unlock_irqrestore(&schan->vc.lock, flags);
1036 
1037 	return 0;
1038 }
1039 
1040 static int sprd_dma_resume(struct dma_chan *chan)
1041 {
1042 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
1043 	unsigned long flags;
1044 
1045 	spin_lock_irqsave(&schan->vc.lock, flags);
1046 	sprd_dma_pause_resume(schan, false);
1047 	spin_unlock_irqrestore(&schan->vc.lock, flags);
1048 
1049 	return 0;
1050 }
1051 
1052 static int sprd_dma_terminate_all(struct dma_chan *chan)
1053 {
1054 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
1055 	struct virt_dma_desc *cur_vd = NULL;
1056 	unsigned long flags;
1057 	LIST_HEAD(head);
1058 
1059 	spin_lock_irqsave(&schan->vc.lock, flags);
1060 	if (schan->cur_desc)
1061 		cur_vd = &schan->cur_desc->vd;
1062 
1063 	sprd_dma_stop(schan);
1064 
1065 	vchan_get_all_descriptors(&schan->vc, &head);
1066 	spin_unlock_irqrestore(&schan->vc.lock, flags);
1067 
1068 	if (cur_vd)
1069 		sprd_dma_free_desc(cur_vd);
1070 
1071 	vchan_dma_desc_free_list(&schan->vc, &head);
1072 	return 0;
1073 }
1074 
1075 static void sprd_dma_free_desc(struct virt_dma_desc *vd)
1076 {
1077 	struct sprd_dma_desc *sdesc = to_sprd_dma_desc(vd);
1078 
1079 	kfree(sdesc);
1080 }
1081 
1082 static bool sprd_dma_filter_fn(struct dma_chan *chan, void *param)
1083 {
1084 	struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
1085 	u32 slave_id = *(u32 *)param;
1086 
1087 	schan->dev_id = slave_id;
1088 	return true;
1089 }
1090 
1091 static int sprd_dma_probe(struct platform_device *pdev)
1092 {
1093 	struct device_node *np = pdev->dev.of_node;
1094 	struct sprd_dma_dev *sdev;
1095 	struct sprd_dma_chn *dma_chn;
1096 	u32 chn_count;
1097 	int ret, i;
1098 
1099 	ret = device_property_read_u32(&pdev->dev, "#dma-channels", &chn_count);
1100 	if (ret) {
1101 		dev_err(&pdev->dev, "get dma channels count failed\n");
1102 		return ret;
1103 	}
1104 
1105 	sdev = devm_kzalloc(&pdev->dev,
1106 			    struct_size(sdev, channels, chn_count),
1107 			    GFP_KERNEL);
1108 	if (!sdev)
1109 		return -ENOMEM;
1110 
1111 	sdev->clk = devm_clk_get(&pdev->dev, "enable");
1112 	if (IS_ERR(sdev->clk)) {
1113 		dev_err(&pdev->dev, "get enable clock failed\n");
1114 		return PTR_ERR(sdev->clk);
1115 	}
1116 
1117 	/* ashb clock is optional for AGCP DMA */
1118 	sdev->ashb_clk = devm_clk_get(&pdev->dev, "ashb_eb");
1119 	if (IS_ERR(sdev->ashb_clk))
1120 		dev_warn(&pdev->dev, "no optional ashb eb clock\n");
1121 
1122 	/*
1123 	 * We have three DMA controllers: AP DMA, AON DMA and AGCP DMA. For AGCP
1124 	 * DMA controller, it can or do not request the irq, which will save
1125 	 * system power without resuming system by DMA interrupts if AGCP DMA
1126 	 * does not request the irq. Thus the DMA interrupts property should
1127 	 * be optional.
1128 	 */
1129 	sdev->irq = platform_get_irq(pdev, 0);
1130 	if (sdev->irq > 0) {
1131 		ret = devm_request_irq(&pdev->dev, sdev->irq, dma_irq_handle,
1132 				       0, "sprd_dma", (void *)sdev);
1133 		if (ret < 0) {
1134 			dev_err(&pdev->dev, "request dma irq failed\n");
1135 			return ret;
1136 		}
1137 	} else {
1138 		dev_warn(&pdev->dev, "no interrupts for the dma controller\n");
1139 	}
1140 
1141 	sdev->glb_base = devm_platform_ioremap_resource(pdev, 0);
1142 	if (IS_ERR(sdev->glb_base))
1143 		return PTR_ERR(sdev->glb_base);
1144 
1145 	dma_cap_set(DMA_MEMCPY, sdev->dma_dev.cap_mask);
1146 	sdev->total_chns = chn_count;
1147 	sdev->dma_dev.chancnt = chn_count;
1148 	INIT_LIST_HEAD(&sdev->dma_dev.channels);
1149 	INIT_LIST_HEAD(&sdev->dma_dev.global_node);
1150 	sdev->dma_dev.dev = &pdev->dev;
1151 	sdev->dma_dev.device_alloc_chan_resources = sprd_dma_alloc_chan_resources;
1152 	sdev->dma_dev.device_free_chan_resources = sprd_dma_free_chan_resources;
1153 	sdev->dma_dev.device_tx_status = sprd_dma_tx_status;
1154 	sdev->dma_dev.device_issue_pending = sprd_dma_issue_pending;
1155 	sdev->dma_dev.device_prep_dma_memcpy = sprd_dma_prep_dma_memcpy;
1156 	sdev->dma_dev.device_prep_slave_sg = sprd_dma_prep_slave_sg;
1157 	sdev->dma_dev.device_config = sprd_dma_slave_config;
1158 	sdev->dma_dev.device_pause = sprd_dma_pause;
1159 	sdev->dma_dev.device_resume = sprd_dma_resume;
1160 	sdev->dma_dev.device_terminate_all = sprd_dma_terminate_all;
1161 
1162 	for (i = 0; i < chn_count; i++) {
1163 		dma_chn = &sdev->channels[i];
1164 		dma_chn->chn_num = i;
1165 		dma_chn->cur_desc = NULL;
1166 		/* get each channel's registers base address. */
1167 		dma_chn->chn_base = sdev->glb_base + SPRD_DMA_CHN_REG_OFFSET +
1168 				    SPRD_DMA_CHN_REG_LENGTH * i;
1169 
1170 		dma_chn->vc.desc_free = sprd_dma_free_desc;
1171 		vchan_init(&dma_chn->vc, &sdev->dma_dev);
1172 	}
1173 
1174 	platform_set_drvdata(pdev, sdev);
1175 	ret = sprd_dma_enable(sdev);
1176 	if (ret)
1177 		return ret;
1178 
1179 	pm_runtime_set_active(&pdev->dev);
1180 	pm_runtime_enable(&pdev->dev);
1181 
1182 	ret = pm_runtime_get_sync(&pdev->dev);
1183 	if (ret < 0)
1184 		goto err_rpm;
1185 
1186 	ret = dma_async_device_register(&sdev->dma_dev);
1187 	if (ret < 0) {
1188 		dev_err(&pdev->dev, "register dma device failed:%d\n", ret);
1189 		goto err_register;
1190 	}
1191 
1192 	sprd_dma_info.dma_cap = sdev->dma_dev.cap_mask;
1193 	ret = of_dma_controller_register(np, of_dma_simple_xlate,
1194 					 &sprd_dma_info);
1195 	if (ret)
1196 		goto err_of_register;
1197 
1198 	pm_runtime_put(&pdev->dev);
1199 	return 0;
1200 
1201 err_of_register:
1202 	dma_async_device_unregister(&sdev->dma_dev);
1203 err_register:
1204 	pm_runtime_put_noidle(&pdev->dev);
1205 	pm_runtime_disable(&pdev->dev);
1206 err_rpm:
1207 	sprd_dma_disable(sdev);
1208 	return ret;
1209 }
1210 
1211 static int sprd_dma_remove(struct platform_device *pdev)
1212 {
1213 	struct sprd_dma_dev *sdev = platform_get_drvdata(pdev);
1214 	struct sprd_dma_chn *c, *cn;
1215 	int ret;
1216 
1217 	ret = pm_runtime_get_sync(&pdev->dev);
1218 	if (ret < 0)
1219 		return ret;
1220 
1221 	/* explicitly free the irq */
1222 	if (sdev->irq > 0)
1223 		devm_free_irq(&pdev->dev, sdev->irq, sdev);
1224 
1225 	list_for_each_entry_safe(c, cn, &sdev->dma_dev.channels,
1226 				 vc.chan.device_node) {
1227 		list_del(&c->vc.chan.device_node);
1228 		tasklet_kill(&c->vc.task);
1229 	}
1230 
1231 	of_dma_controller_free(pdev->dev.of_node);
1232 	dma_async_device_unregister(&sdev->dma_dev);
1233 	sprd_dma_disable(sdev);
1234 
1235 	pm_runtime_put_noidle(&pdev->dev);
1236 	pm_runtime_disable(&pdev->dev);
1237 	return 0;
1238 }
1239 
1240 static const struct of_device_id sprd_dma_match[] = {
1241 	{ .compatible = "sprd,sc9860-dma", },
1242 	{},
1243 };
1244 
1245 static int __maybe_unused sprd_dma_runtime_suspend(struct device *dev)
1246 {
1247 	struct sprd_dma_dev *sdev = dev_get_drvdata(dev);
1248 
1249 	sprd_dma_disable(sdev);
1250 	return 0;
1251 }
1252 
1253 static int __maybe_unused sprd_dma_runtime_resume(struct device *dev)
1254 {
1255 	struct sprd_dma_dev *sdev = dev_get_drvdata(dev);
1256 	int ret;
1257 
1258 	ret = sprd_dma_enable(sdev);
1259 	if (ret)
1260 		dev_err(sdev->dma_dev.dev, "enable dma failed\n");
1261 
1262 	return ret;
1263 }
1264 
1265 static const struct dev_pm_ops sprd_dma_pm_ops = {
1266 	SET_RUNTIME_PM_OPS(sprd_dma_runtime_suspend,
1267 			   sprd_dma_runtime_resume,
1268 			   NULL)
1269 };
1270 
1271 static struct platform_driver sprd_dma_driver = {
1272 	.probe = sprd_dma_probe,
1273 	.remove = sprd_dma_remove,
1274 	.driver = {
1275 		.name = "sprd-dma",
1276 		.of_match_table = sprd_dma_match,
1277 		.pm = &sprd_dma_pm_ops,
1278 	},
1279 };
1280 module_platform_driver(sprd_dma_driver);
1281 
1282 MODULE_LICENSE("GPL v2");
1283 MODULE_DESCRIPTION("DMA driver for Spreadtrum");
1284 MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");
1285 MODULE_AUTHOR("Eric Long <eric.long@spreadtrum.com>");
1286 MODULE_ALIAS("platform:sprd-dma");
1287