xref: /linux/drivers/dma/sun6i-dma.c (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2013-2014 Allwinner Tech Co., Ltd
4  * Author: Sugar <shuge@allwinnertech.com>
5  *
6  * Copyright (C) 2014 Maxime Ripard
7  * Maxime Ripard <maxime.ripard@free-electrons.com>
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/dmaengine.h>
13 #include <linux/dmapool.h>
14 #include <linux/interrupt.h>
15 #include <linux/module.h>
16 #include <linux/of_dma.h>
17 #include <linux/of_device.h>
18 #include <linux/platform_device.h>
19 #include <linux/reset.h>
20 #include <linux/slab.h>
21 #include <linux/types.h>
22 
23 #include "virt-dma.h"
24 
25 /*
26  * Common registers
27  */
28 #define DMA_IRQ_EN(x)		((x) * 0x04)
29 #define DMA_IRQ_HALF			BIT(0)
30 #define DMA_IRQ_PKG			BIT(1)
31 #define DMA_IRQ_QUEUE			BIT(2)
32 
33 #define DMA_IRQ_CHAN_NR			8
34 #define DMA_IRQ_CHAN_WIDTH		4
35 
36 
37 #define DMA_IRQ_STAT(x)		((x) * 0x04 + 0x10)
38 
39 #define DMA_STAT		0x30
40 
41 /* Offset between DMA_IRQ_EN and DMA_IRQ_STAT limits number of channels */
42 #define DMA_MAX_CHANNELS	(DMA_IRQ_CHAN_NR * 0x10 / 4)
43 
44 /*
45  * sun8i specific registers
46  */
47 #define SUN8I_DMA_GATE		0x20
48 #define SUN8I_DMA_GATE_ENABLE	0x4
49 
50 #define SUNXI_H3_SECURE_REG		0x20
51 #define SUNXI_H3_DMA_GATE		0x28
52 #define SUNXI_H3_DMA_GATE_ENABLE	0x4
53 /*
54  * Channels specific registers
55  */
56 #define DMA_CHAN_ENABLE		0x00
57 #define DMA_CHAN_ENABLE_START		BIT(0)
58 #define DMA_CHAN_ENABLE_STOP		0
59 
60 #define DMA_CHAN_PAUSE		0x04
61 #define DMA_CHAN_PAUSE_PAUSE		BIT(1)
62 #define DMA_CHAN_PAUSE_RESUME		0
63 
64 #define DMA_CHAN_LLI_ADDR	0x08
65 
66 #define DMA_CHAN_CUR_CFG	0x0c
67 #define DMA_CHAN_MAX_DRQ_A31		0x1f
68 #define DMA_CHAN_MAX_DRQ_H6		0x3f
69 #define DMA_CHAN_CFG_SRC_DRQ_A31(x)	((x) & DMA_CHAN_MAX_DRQ_A31)
70 #define DMA_CHAN_CFG_SRC_DRQ_H6(x)	((x) & DMA_CHAN_MAX_DRQ_H6)
71 #define DMA_CHAN_CFG_SRC_MODE_A31(x)	(((x) & 0x1) << 5)
72 #define DMA_CHAN_CFG_SRC_MODE_H6(x)	(((x) & 0x1) << 8)
73 #define DMA_CHAN_CFG_SRC_BURST_A31(x)	(((x) & 0x3) << 7)
74 #define DMA_CHAN_CFG_SRC_BURST_H3(x)	(((x) & 0x3) << 6)
75 #define DMA_CHAN_CFG_SRC_WIDTH(x)	(((x) & 0x3) << 9)
76 
77 #define DMA_CHAN_CFG_DST_DRQ_A31(x)	(DMA_CHAN_CFG_SRC_DRQ_A31(x) << 16)
78 #define DMA_CHAN_CFG_DST_DRQ_H6(x)	(DMA_CHAN_CFG_SRC_DRQ_H6(x) << 16)
79 #define DMA_CHAN_CFG_DST_MODE_A31(x)	(DMA_CHAN_CFG_SRC_MODE_A31(x) << 16)
80 #define DMA_CHAN_CFG_DST_MODE_H6(x)	(DMA_CHAN_CFG_SRC_MODE_H6(x) << 16)
81 #define DMA_CHAN_CFG_DST_BURST_A31(x)	(DMA_CHAN_CFG_SRC_BURST_A31(x) << 16)
82 #define DMA_CHAN_CFG_DST_BURST_H3(x)	(DMA_CHAN_CFG_SRC_BURST_H3(x) << 16)
83 #define DMA_CHAN_CFG_DST_WIDTH(x)	(DMA_CHAN_CFG_SRC_WIDTH(x) << 16)
84 
85 #define DMA_CHAN_CUR_SRC	0x10
86 
87 #define DMA_CHAN_CUR_DST	0x14
88 
89 #define DMA_CHAN_CUR_CNT	0x18
90 
91 #define DMA_CHAN_CUR_PARA	0x1c
92 
93 
94 /*
95  * Various hardware related defines
96  */
97 #define LLI_LAST_ITEM	0xfffff800
98 #define NORMAL_WAIT	8
99 #define DRQ_SDRAM	1
100 #define LINEAR_MODE     0
101 #define IO_MODE         1
102 
103 /* forward declaration */
104 struct sun6i_dma_dev;
105 
106 /*
107  * Hardware channels / ports representation
108  *
109  * The hardware is used in several SoCs, with differing numbers
110  * of channels and endpoints. This structure ties those numbers
111  * to a certain compatible string.
112  */
113 struct sun6i_dma_config {
114 	u32 nr_max_channels;
115 	u32 nr_max_requests;
116 	u32 nr_max_vchans;
117 	/*
118 	 * In the datasheets/user manuals of newer Allwinner SoCs, a special
119 	 * bit (bit 2 at register 0x20) is present.
120 	 * It's named "DMA MCLK interface circuit auto gating bit" in the
121 	 * documents, and the footnote of this register says that this bit
122 	 * should be set up when initializing the DMA controller.
123 	 * Allwinner A23/A33 user manuals do not have this bit documented,
124 	 * however these SoCs really have and need this bit, as seen in the
125 	 * BSP kernel source code.
126 	 */
127 	void (*clock_autogate_enable)(struct sun6i_dma_dev *);
128 	void (*set_burst_length)(u32 *p_cfg, s8 src_burst, s8 dst_burst);
129 	void (*set_drq)(u32 *p_cfg, s8 src_drq, s8 dst_drq);
130 	void (*set_mode)(u32 *p_cfg, s8 src_mode, s8 dst_mode);
131 	u32 src_burst_lengths;
132 	u32 dst_burst_lengths;
133 	u32 src_addr_widths;
134 	u32 dst_addr_widths;
135 	bool has_mbus_clk;
136 };
137 
138 /*
139  * Hardware representation of the LLI
140  *
141  * The hardware will be fed the physical address of this structure,
142  * and read its content in order to start the transfer.
143  */
144 struct sun6i_dma_lli {
145 	u32			cfg;
146 	u32			src;
147 	u32			dst;
148 	u32			len;
149 	u32			para;
150 	u32			p_lli_next;
151 
152 	/*
153 	 * This field is not used by the DMA controller, but will be
154 	 * used by the CPU to go through the list (mostly for dumping
155 	 * or freeing it).
156 	 */
157 	struct sun6i_dma_lli	*v_lli_next;
158 };
159 
160 
161 struct sun6i_desc {
162 	struct virt_dma_desc	vd;
163 	dma_addr_t		p_lli;
164 	struct sun6i_dma_lli	*v_lli;
165 };
166 
167 struct sun6i_pchan {
168 	u32			idx;
169 	void __iomem		*base;
170 	struct sun6i_vchan	*vchan;
171 	struct sun6i_desc	*desc;
172 	struct sun6i_desc	*done;
173 };
174 
175 struct sun6i_vchan {
176 	struct virt_dma_chan	vc;
177 	struct list_head	node;
178 	struct dma_slave_config	cfg;
179 	struct sun6i_pchan	*phy;
180 	u8			port;
181 	u8			irq_type;
182 	bool			cyclic;
183 };
184 
185 struct sun6i_dma_dev {
186 	struct dma_device	slave;
187 	void __iomem		*base;
188 	struct clk		*clk;
189 	struct clk		*clk_mbus;
190 	int			irq;
191 	spinlock_t		lock;
192 	struct reset_control	*rstc;
193 	struct tasklet_struct	task;
194 	atomic_t		tasklet_shutdown;
195 	struct list_head	pending;
196 	struct dma_pool		*pool;
197 	struct sun6i_pchan	*pchans;
198 	struct sun6i_vchan	*vchans;
199 	const struct sun6i_dma_config *cfg;
200 	u32			num_pchans;
201 	u32			num_vchans;
202 	u32			max_request;
203 };
204 
205 static struct device *chan2dev(struct dma_chan *chan)
206 {
207 	return &chan->dev->device;
208 }
209 
210 static inline struct sun6i_dma_dev *to_sun6i_dma_dev(struct dma_device *d)
211 {
212 	return container_of(d, struct sun6i_dma_dev, slave);
213 }
214 
215 static inline struct sun6i_vchan *to_sun6i_vchan(struct dma_chan *chan)
216 {
217 	return container_of(chan, struct sun6i_vchan, vc.chan);
218 }
219 
220 static inline struct sun6i_desc *
221 to_sun6i_desc(struct dma_async_tx_descriptor *tx)
222 {
223 	return container_of(tx, struct sun6i_desc, vd.tx);
224 }
225 
226 static inline void sun6i_dma_dump_com_regs(struct sun6i_dma_dev *sdev)
227 {
228 	dev_dbg(sdev->slave.dev, "Common register:\n"
229 		"\tmask0(%04x): 0x%08x\n"
230 		"\tmask1(%04x): 0x%08x\n"
231 		"\tpend0(%04x): 0x%08x\n"
232 		"\tpend1(%04x): 0x%08x\n"
233 		"\tstats(%04x): 0x%08x\n",
234 		DMA_IRQ_EN(0), readl(sdev->base + DMA_IRQ_EN(0)),
235 		DMA_IRQ_EN(1), readl(sdev->base + DMA_IRQ_EN(1)),
236 		DMA_IRQ_STAT(0), readl(sdev->base + DMA_IRQ_STAT(0)),
237 		DMA_IRQ_STAT(1), readl(sdev->base + DMA_IRQ_STAT(1)),
238 		DMA_STAT, readl(sdev->base + DMA_STAT));
239 }
240 
241 static inline void sun6i_dma_dump_chan_regs(struct sun6i_dma_dev *sdev,
242 					    struct sun6i_pchan *pchan)
243 {
244 	phys_addr_t reg = virt_to_phys(pchan->base);
245 
246 	dev_dbg(sdev->slave.dev, "Chan %d reg: %pa\n"
247 		"\t___en(%04x): \t0x%08x\n"
248 		"\tpause(%04x): \t0x%08x\n"
249 		"\tstart(%04x): \t0x%08x\n"
250 		"\t__cfg(%04x): \t0x%08x\n"
251 		"\t__src(%04x): \t0x%08x\n"
252 		"\t__dst(%04x): \t0x%08x\n"
253 		"\tcount(%04x): \t0x%08x\n"
254 		"\t_para(%04x): \t0x%08x\n\n",
255 		pchan->idx, &reg,
256 		DMA_CHAN_ENABLE,
257 		readl(pchan->base + DMA_CHAN_ENABLE),
258 		DMA_CHAN_PAUSE,
259 		readl(pchan->base + DMA_CHAN_PAUSE),
260 		DMA_CHAN_LLI_ADDR,
261 		readl(pchan->base + DMA_CHAN_LLI_ADDR),
262 		DMA_CHAN_CUR_CFG,
263 		readl(pchan->base + DMA_CHAN_CUR_CFG),
264 		DMA_CHAN_CUR_SRC,
265 		readl(pchan->base + DMA_CHAN_CUR_SRC),
266 		DMA_CHAN_CUR_DST,
267 		readl(pchan->base + DMA_CHAN_CUR_DST),
268 		DMA_CHAN_CUR_CNT,
269 		readl(pchan->base + DMA_CHAN_CUR_CNT),
270 		DMA_CHAN_CUR_PARA,
271 		readl(pchan->base + DMA_CHAN_CUR_PARA));
272 }
273 
274 static inline s8 convert_burst(u32 maxburst)
275 {
276 	switch (maxburst) {
277 	case 1:
278 		return 0;
279 	case 4:
280 		return 1;
281 	case 8:
282 		return 2;
283 	case 16:
284 		return 3;
285 	default:
286 		return -EINVAL;
287 	}
288 }
289 
290 static inline s8 convert_buswidth(enum dma_slave_buswidth addr_width)
291 {
292 	return ilog2(addr_width);
293 }
294 
295 static void sun6i_enable_clock_autogate_a23(struct sun6i_dma_dev *sdev)
296 {
297 	writel(SUN8I_DMA_GATE_ENABLE, sdev->base + SUN8I_DMA_GATE);
298 }
299 
300 static void sun6i_enable_clock_autogate_h3(struct sun6i_dma_dev *sdev)
301 {
302 	writel(SUNXI_H3_DMA_GATE_ENABLE, sdev->base + SUNXI_H3_DMA_GATE);
303 }
304 
305 static void sun6i_set_burst_length_a31(u32 *p_cfg, s8 src_burst, s8 dst_burst)
306 {
307 	*p_cfg |= DMA_CHAN_CFG_SRC_BURST_A31(src_burst) |
308 		  DMA_CHAN_CFG_DST_BURST_A31(dst_burst);
309 }
310 
311 static void sun6i_set_burst_length_h3(u32 *p_cfg, s8 src_burst, s8 dst_burst)
312 {
313 	*p_cfg |= DMA_CHAN_CFG_SRC_BURST_H3(src_burst) |
314 		  DMA_CHAN_CFG_DST_BURST_H3(dst_burst);
315 }
316 
317 static void sun6i_set_drq_a31(u32 *p_cfg, s8 src_drq, s8 dst_drq)
318 {
319 	*p_cfg |= DMA_CHAN_CFG_SRC_DRQ_A31(src_drq) |
320 		  DMA_CHAN_CFG_DST_DRQ_A31(dst_drq);
321 }
322 
323 static void sun6i_set_drq_h6(u32 *p_cfg, s8 src_drq, s8 dst_drq)
324 {
325 	*p_cfg |= DMA_CHAN_CFG_SRC_DRQ_H6(src_drq) |
326 		  DMA_CHAN_CFG_DST_DRQ_H6(dst_drq);
327 }
328 
329 static void sun6i_set_mode_a31(u32 *p_cfg, s8 src_mode, s8 dst_mode)
330 {
331 	*p_cfg |= DMA_CHAN_CFG_SRC_MODE_A31(src_mode) |
332 		  DMA_CHAN_CFG_DST_MODE_A31(dst_mode);
333 }
334 
335 static void sun6i_set_mode_h6(u32 *p_cfg, s8 src_mode, s8 dst_mode)
336 {
337 	*p_cfg |= DMA_CHAN_CFG_SRC_MODE_H6(src_mode) |
338 		  DMA_CHAN_CFG_DST_MODE_H6(dst_mode);
339 }
340 
341 static size_t sun6i_get_chan_size(struct sun6i_pchan *pchan)
342 {
343 	struct sun6i_desc *txd = pchan->desc;
344 	struct sun6i_dma_lli *lli;
345 	size_t bytes;
346 	dma_addr_t pos;
347 
348 	pos = readl(pchan->base + DMA_CHAN_LLI_ADDR);
349 	bytes = readl(pchan->base + DMA_CHAN_CUR_CNT);
350 
351 	if (pos == LLI_LAST_ITEM)
352 		return bytes;
353 
354 	for (lli = txd->v_lli; lli; lli = lli->v_lli_next) {
355 		if (lli->p_lli_next == pos) {
356 			for (lli = lli->v_lli_next; lli; lli = lli->v_lli_next)
357 				bytes += lli->len;
358 			break;
359 		}
360 	}
361 
362 	return bytes;
363 }
364 
365 static void *sun6i_dma_lli_add(struct sun6i_dma_lli *prev,
366 			       struct sun6i_dma_lli *next,
367 			       dma_addr_t next_phy,
368 			       struct sun6i_desc *txd)
369 {
370 	if ((!prev && !txd) || !next)
371 		return NULL;
372 
373 	if (!prev) {
374 		txd->p_lli = next_phy;
375 		txd->v_lli = next;
376 	} else {
377 		prev->p_lli_next = next_phy;
378 		prev->v_lli_next = next;
379 	}
380 
381 	next->p_lli_next = LLI_LAST_ITEM;
382 	next->v_lli_next = NULL;
383 
384 	return next;
385 }
386 
387 static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan,
388 				      struct sun6i_dma_lli *lli)
389 {
390 	phys_addr_t p_lli = virt_to_phys(lli);
391 
392 	dev_dbg(chan2dev(&vchan->vc.chan),
393 		"\n\tdesc:   p - %pa v - 0x%p\n"
394 		"\t\tc - 0x%08x s - 0x%08x d - 0x%08x\n"
395 		"\t\tl - 0x%08x p - 0x%08x n - 0x%08x\n",
396 		&p_lli, lli,
397 		lli->cfg, lli->src, lli->dst,
398 		lli->len, lli->para, lli->p_lli_next);
399 }
400 
401 static void sun6i_dma_free_desc(struct virt_dma_desc *vd)
402 {
403 	struct sun6i_desc *txd = to_sun6i_desc(&vd->tx);
404 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device);
405 	struct sun6i_dma_lli *v_lli, *v_next;
406 	dma_addr_t p_lli, p_next;
407 
408 	if (unlikely(!txd))
409 		return;
410 
411 	p_lli = txd->p_lli;
412 	v_lli = txd->v_lli;
413 
414 	while (v_lli) {
415 		v_next = v_lli->v_lli_next;
416 		p_next = v_lli->p_lli_next;
417 
418 		dma_pool_free(sdev->pool, v_lli, p_lli);
419 
420 		v_lli = v_next;
421 		p_lli = p_next;
422 	}
423 
424 	kfree(txd);
425 }
426 
427 static int sun6i_dma_start_desc(struct sun6i_vchan *vchan)
428 {
429 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device);
430 	struct virt_dma_desc *desc = vchan_next_desc(&vchan->vc);
431 	struct sun6i_pchan *pchan = vchan->phy;
432 	u32 irq_val, irq_reg, irq_offset;
433 
434 	if (!pchan)
435 		return -EAGAIN;
436 
437 	if (!desc) {
438 		pchan->desc = NULL;
439 		pchan->done = NULL;
440 		return -EAGAIN;
441 	}
442 
443 	list_del(&desc->node);
444 
445 	pchan->desc = to_sun6i_desc(&desc->tx);
446 	pchan->done = NULL;
447 
448 	sun6i_dma_dump_lli(vchan, pchan->desc->v_lli);
449 
450 	irq_reg = pchan->idx / DMA_IRQ_CHAN_NR;
451 	irq_offset = pchan->idx % DMA_IRQ_CHAN_NR;
452 
453 	vchan->irq_type = vchan->cyclic ? DMA_IRQ_PKG : DMA_IRQ_QUEUE;
454 
455 	irq_val = readl(sdev->base + DMA_IRQ_EN(irq_reg));
456 	irq_val &= ~((DMA_IRQ_HALF | DMA_IRQ_PKG | DMA_IRQ_QUEUE) <<
457 			(irq_offset * DMA_IRQ_CHAN_WIDTH));
458 	irq_val |= vchan->irq_type << (irq_offset * DMA_IRQ_CHAN_WIDTH);
459 	writel(irq_val, sdev->base + DMA_IRQ_EN(irq_reg));
460 
461 	writel(pchan->desc->p_lli, pchan->base + DMA_CHAN_LLI_ADDR);
462 	writel(DMA_CHAN_ENABLE_START, pchan->base + DMA_CHAN_ENABLE);
463 
464 	sun6i_dma_dump_com_regs(sdev);
465 	sun6i_dma_dump_chan_regs(sdev, pchan);
466 
467 	return 0;
468 }
469 
470 static void sun6i_dma_tasklet(struct tasklet_struct *t)
471 {
472 	struct sun6i_dma_dev *sdev = from_tasklet(sdev, t, task);
473 	struct sun6i_vchan *vchan;
474 	struct sun6i_pchan *pchan;
475 	unsigned int pchan_alloc = 0;
476 	unsigned int pchan_idx;
477 
478 	list_for_each_entry(vchan, &sdev->slave.channels, vc.chan.device_node) {
479 		spin_lock_irq(&vchan->vc.lock);
480 
481 		pchan = vchan->phy;
482 
483 		if (pchan && pchan->done) {
484 			if (sun6i_dma_start_desc(vchan)) {
485 				/*
486 				 * No current txd associated with this channel
487 				 */
488 				dev_dbg(sdev->slave.dev, "pchan %u: free\n",
489 					pchan->idx);
490 
491 				/* Mark this channel free */
492 				vchan->phy = NULL;
493 				pchan->vchan = NULL;
494 			}
495 		}
496 		spin_unlock_irq(&vchan->vc.lock);
497 	}
498 
499 	spin_lock_irq(&sdev->lock);
500 	for (pchan_idx = 0; pchan_idx < sdev->num_pchans; pchan_idx++) {
501 		pchan = &sdev->pchans[pchan_idx];
502 
503 		if (pchan->vchan || list_empty(&sdev->pending))
504 			continue;
505 
506 		vchan = list_first_entry(&sdev->pending,
507 					 struct sun6i_vchan, node);
508 
509 		/* Remove from pending channels */
510 		list_del_init(&vchan->node);
511 		pchan_alloc |= BIT(pchan_idx);
512 
513 		/* Mark this channel allocated */
514 		pchan->vchan = vchan;
515 		vchan->phy = pchan;
516 		dev_dbg(sdev->slave.dev, "pchan %u: alloc vchan %p\n",
517 			pchan->idx, &vchan->vc);
518 	}
519 	spin_unlock_irq(&sdev->lock);
520 
521 	for (pchan_idx = 0; pchan_idx < sdev->num_pchans; pchan_idx++) {
522 		if (!(pchan_alloc & BIT(pchan_idx)))
523 			continue;
524 
525 		pchan = sdev->pchans + pchan_idx;
526 		vchan = pchan->vchan;
527 		if (vchan) {
528 			spin_lock_irq(&vchan->vc.lock);
529 			sun6i_dma_start_desc(vchan);
530 			spin_unlock_irq(&vchan->vc.lock);
531 		}
532 	}
533 }
534 
535 static irqreturn_t sun6i_dma_interrupt(int irq, void *dev_id)
536 {
537 	struct sun6i_dma_dev *sdev = dev_id;
538 	struct sun6i_vchan *vchan;
539 	struct sun6i_pchan *pchan;
540 	int i, j, ret = IRQ_NONE;
541 	u32 status;
542 
543 	for (i = 0; i < sdev->num_pchans / DMA_IRQ_CHAN_NR; i++) {
544 		status = readl(sdev->base + DMA_IRQ_STAT(i));
545 		if (!status)
546 			continue;
547 
548 		dev_dbg(sdev->slave.dev, "DMA irq status %s: 0x%x\n",
549 			i ? "high" : "low", status);
550 
551 		writel(status, sdev->base + DMA_IRQ_STAT(i));
552 
553 		for (j = 0; (j < DMA_IRQ_CHAN_NR) && status; j++) {
554 			pchan = sdev->pchans + j;
555 			vchan = pchan->vchan;
556 			if (vchan && (status & vchan->irq_type)) {
557 				if (vchan->cyclic) {
558 					vchan_cyclic_callback(&pchan->desc->vd);
559 				} else {
560 					spin_lock(&vchan->vc.lock);
561 					vchan_cookie_complete(&pchan->desc->vd);
562 					pchan->done = pchan->desc;
563 					spin_unlock(&vchan->vc.lock);
564 				}
565 			}
566 
567 			status = status >> DMA_IRQ_CHAN_WIDTH;
568 		}
569 
570 		if (!atomic_read(&sdev->tasklet_shutdown))
571 			tasklet_schedule(&sdev->task);
572 		ret = IRQ_HANDLED;
573 	}
574 
575 	return ret;
576 }
577 
578 static int set_config(struct sun6i_dma_dev *sdev,
579 			struct dma_slave_config *sconfig,
580 			enum dma_transfer_direction direction,
581 			u32 *p_cfg)
582 {
583 	enum dma_slave_buswidth src_addr_width, dst_addr_width;
584 	u32 src_maxburst, dst_maxburst;
585 	s8 src_width, dst_width, src_burst, dst_burst;
586 
587 	src_addr_width = sconfig->src_addr_width;
588 	dst_addr_width = sconfig->dst_addr_width;
589 	src_maxburst = sconfig->src_maxburst;
590 	dst_maxburst = sconfig->dst_maxburst;
591 
592 	switch (direction) {
593 	case DMA_MEM_TO_DEV:
594 		if (src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
595 			src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
596 		src_maxburst = src_maxburst ? src_maxburst : 8;
597 		break;
598 	case DMA_DEV_TO_MEM:
599 		if (dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
600 			dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
601 		dst_maxburst = dst_maxburst ? dst_maxburst : 8;
602 		break;
603 	default:
604 		return -EINVAL;
605 	}
606 
607 	if (!(BIT(src_addr_width) & sdev->slave.src_addr_widths))
608 		return -EINVAL;
609 	if (!(BIT(dst_addr_width) & sdev->slave.dst_addr_widths))
610 		return -EINVAL;
611 	if (!(BIT(src_maxburst) & sdev->cfg->src_burst_lengths))
612 		return -EINVAL;
613 	if (!(BIT(dst_maxburst) & sdev->cfg->dst_burst_lengths))
614 		return -EINVAL;
615 
616 	src_width = convert_buswidth(src_addr_width);
617 	dst_width = convert_buswidth(dst_addr_width);
618 	dst_burst = convert_burst(dst_maxburst);
619 	src_burst = convert_burst(src_maxburst);
620 
621 	*p_cfg = DMA_CHAN_CFG_SRC_WIDTH(src_width) |
622 		DMA_CHAN_CFG_DST_WIDTH(dst_width);
623 
624 	sdev->cfg->set_burst_length(p_cfg, src_burst, dst_burst);
625 
626 	return 0;
627 }
628 
629 static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_memcpy(
630 		struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
631 		size_t len, unsigned long flags)
632 {
633 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
634 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
635 	struct sun6i_dma_lli *v_lli;
636 	struct sun6i_desc *txd;
637 	dma_addr_t p_lli;
638 	s8 burst, width;
639 
640 	dev_dbg(chan2dev(chan),
641 		"%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n",
642 		__func__, vchan->vc.chan.chan_id, &dest, &src, len, flags);
643 
644 	if (!len)
645 		return NULL;
646 
647 	txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
648 	if (!txd)
649 		return NULL;
650 
651 	v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
652 	if (!v_lli) {
653 		dev_err(sdev->slave.dev, "Failed to alloc lli memory\n");
654 		goto err_txd_free;
655 	}
656 
657 	v_lli->src = src;
658 	v_lli->dst = dest;
659 	v_lli->len = len;
660 	v_lli->para = NORMAL_WAIT;
661 
662 	burst = convert_burst(8);
663 	width = convert_buswidth(DMA_SLAVE_BUSWIDTH_4_BYTES);
664 	v_lli->cfg = DMA_CHAN_CFG_SRC_WIDTH(width) |
665 		DMA_CHAN_CFG_DST_WIDTH(width);
666 
667 	sdev->cfg->set_burst_length(&v_lli->cfg, burst, burst);
668 	sdev->cfg->set_drq(&v_lli->cfg, DRQ_SDRAM, DRQ_SDRAM);
669 	sdev->cfg->set_mode(&v_lli->cfg, LINEAR_MODE, LINEAR_MODE);
670 
671 	sun6i_dma_lli_add(NULL, v_lli, p_lli, txd);
672 
673 	sun6i_dma_dump_lli(vchan, v_lli);
674 
675 	return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
676 
677 err_txd_free:
678 	kfree(txd);
679 	return NULL;
680 }
681 
682 static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg(
683 		struct dma_chan *chan, struct scatterlist *sgl,
684 		unsigned int sg_len, enum dma_transfer_direction dir,
685 		unsigned long flags, void *context)
686 {
687 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
688 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
689 	struct dma_slave_config *sconfig = &vchan->cfg;
690 	struct sun6i_dma_lli *v_lli, *prev = NULL;
691 	struct sun6i_desc *txd;
692 	struct scatterlist *sg;
693 	dma_addr_t p_lli;
694 	u32 lli_cfg;
695 	int i, ret;
696 
697 	if (!sgl)
698 		return NULL;
699 
700 	ret = set_config(sdev, sconfig, dir, &lli_cfg);
701 	if (ret) {
702 		dev_err(chan2dev(chan), "Invalid DMA configuration\n");
703 		return NULL;
704 	}
705 
706 	txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
707 	if (!txd)
708 		return NULL;
709 
710 	for_each_sg(sgl, sg, sg_len, i) {
711 		v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
712 		if (!v_lli)
713 			goto err_lli_free;
714 
715 		v_lli->len = sg_dma_len(sg);
716 		v_lli->para = NORMAL_WAIT;
717 
718 		if (dir == DMA_MEM_TO_DEV) {
719 			v_lli->src = sg_dma_address(sg);
720 			v_lli->dst = sconfig->dst_addr;
721 			v_lli->cfg = lli_cfg;
722 			sdev->cfg->set_drq(&v_lli->cfg, DRQ_SDRAM, vchan->port);
723 			sdev->cfg->set_mode(&v_lli->cfg, LINEAR_MODE, IO_MODE);
724 
725 			dev_dbg(chan2dev(chan),
726 				"%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n",
727 				__func__, vchan->vc.chan.chan_id,
728 				&sconfig->dst_addr, &sg_dma_address(sg),
729 				sg_dma_len(sg), flags);
730 
731 		} else {
732 			v_lli->src = sconfig->src_addr;
733 			v_lli->dst = sg_dma_address(sg);
734 			v_lli->cfg = lli_cfg;
735 			sdev->cfg->set_drq(&v_lli->cfg, vchan->port, DRQ_SDRAM);
736 			sdev->cfg->set_mode(&v_lli->cfg, IO_MODE, LINEAR_MODE);
737 
738 			dev_dbg(chan2dev(chan),
739 				"%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n",
740 				__func__, vchan->vc.chan.chan_id,
741 				&sg_dma_address(sg), &sconfig->src_addr,
742 				sg_dma_len(sg), flags);
743 		}
744 
745 		prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd);
746 	}
747 
748 	dev_dbg(chan2dev(chan), "First: %pad\n", &txd->p_lli);
749 	for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
750 		sun6i_dma_dump_lli(vchan, prev);
751 
752 	return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
753 
754 err_lli_free:
755 	for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
756 		dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
757 	kfree(txd);
758 	return NULL;
759 }
760 
761 static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_cyclic(
762 					struct dma_chan *chan,
763 					dma_addr_t buf_addr,
764 					size_t buf_len,
765 					size_t period_len,
766 					enum dma_transfer_direction dir,
767 					unsigned long flags)
768 {
769 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
770 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
771 	struct dma_slave_config *sconfig = &vchan->cfg;
772 	struct sun6i_dma_lli *v_lli, *prev = NULL;
773 	struct sun6i_desc *txd;
774 	dma_addr_t p_lli;
775 	u32 lli_cfg;
776 	unsigned int i, periods = buf_len / period_len;
777 	int ret;
778 
779 	ret = set_config(sdev, sconfig, dir, &lli_cfg);
780 	if (ret) {
781 		dev_err(chan2dev(chan), "Invalid DMA configuration\n");
782 		return NULL;
783 	}
784 
785 	txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
786 	if (!txd)
787 		return NULL;
788 
789 	for (i = 0; i < periods; i++) {
790 		v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
791 		if (!v_lli) {
792 			dev_err(sdev->slave.dev, "Failed to alloc lli memory\n");
793 			goto err_lli_free;
794 		}
795 
796 		v_lli->len = period_len;
797 		v_lli->para = NORMAL_WAIT;
798 
799 		if (dir == DMA_MEM_TO_DEV) {
800 			v_lli->src = buf_addr + period_len * i;
801 			v_lli->dst = sconfig->dst_addr;
802 			v_lli->cfg = lli_cfg;
803 			sdev->cfg->set_drq(&v_lli->cfg, DRQ_SDRAM, vchan->port);
804 			sdev->cfg->set_mode(&v_lli->cfg, LINEAR_MODE, IO_MODE);
805 		} else {
806 			v_lli->src = sconfig->src_addr;
807 			v_lli->dst = buf_addr + period_len * i;
808 			v_lli->cfg = lli_cfg;
809 			sdev->cfg->set_drq(&v_lli->cfg, vchan->port, DRQ_SDRAM);
810 			sdev->cfg->set_mode(&v_lli->cfg, IO_MODE, LINEAR_MODE);
811 		}
812 
813 		prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd);
814 	}
815 
816 	prev->p_lli_next = txd->p_lli;		/* cyclic list */
817 
818 	vchan->cyclic = true;
819 
820 	return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
821 
822 err_lli_free:
823 	for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
824 		dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
825 	kfree(txd);
826 	return NULL;
827 }
828 
829 static int sun6i_dma_config(struct dma_chan *chan,
830 			    struct dma_slave_config *config)
831 {
832 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
833 
834 	memcpy(&vchan->cfg, config, sizeof(*config));
835 
836 	return 0;
837 }
838 
839 static int sun6i_dma_pause(struct dma_chan *chan)
840 {
841 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
842 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
843 	struct sun6i_pchan *pchan = vchan->phy;
844 
845 	dev_dbg(chan2dev(chan), "vchan %p: pause\n", &vchan->vc);
846 
847 	if (pchan) {
848 		writel(DMA_CHAN_PAUSE_PAUSE,
849 		       pchan->base + DMA_CHAN_PAUSE);
850 	} else {
851 		spin_lock(&sdev->lock);
852 		list_del_init(&vchan->node);
853 		spin_unlock(&sdev->lock);
854 	}
855 
856 	return 0;
857 }
858 
859 static int sun6i_dma_resume(struct dma_chan *chan)
860 {
861 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
862 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
863 	struct sun6i_pchan *pchan = vchan->phy;
864 	unsigned long flags;
865 
866 	dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc);
867 
868 	spin_lock_irqsave(&vchan->vc.lock, flags);
869 
870 	if (pchan) {
871 		writel(DMA_CHAN_PAUSE_RESUME,
872 		       pchan->base + DMA_CHAN_PAUSE);
873 	} else if (!list_empty(&vchan->vc.desc_issued)) {
874 		spin_lock(&sdev->lock);
875 		list_add_tail(&vchan->node, &sdev->pending);
876 		spin_unlock(&sdev->lock);
877 	}
878 
879 	spin_unlock_irqrestore(&vchan->vc.lock, flags);
880 
881 	return 0;
882 }
883 
884 static int sun6i_dma_terminate_all(struct dma_chan *chan)
885 {
886 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
887 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
888 	struct sun6i_pchan *pchan = vchan->phy;
889 	unsigned long flags;
890 	LIST_HEAD(head);
891 
892 	spin_lock(&sdev->lock);
893 	list_del_init(&vchan->node);
894 	spin_unlock(&sdev->lock);
895 
896 	spin_lock_irqsave(&vchan->vc.lock, flags);
897 
898 	if (vchan->cyclic) {
899 		vchan->cyclic = false;
900 		if (pchan && pchan->desc) {
901 			struct virt_dma_desc *vd = &pchan->desc->vd;
902 			struct virt_dma_chan *vc = &vchan->vc;
903 
904 			list_add_tail(&vd->node, &vc->desc_completed);
905 		}
906 	}
907 
908 	vchan_get_all_descriptors(&vchan->vc, &head);
909 
910 	if (pchan) {
911 		writel(DMA_CHAN_ENABLE_STOP, pchan->base + DMA_CHAN_ENABLE);
912 		writel(DMA_CHAN_PAUSE_RESUME, pchan->base + DMA_CHAN_PAUSE);
913 
914 		vchan->phy = NULL;
915 		pchan->vchan = NULL;
916 		pchan->desc = NULL;
917 		pchan->done = NULL;
918 	}
919 
920 	spin_unlock_irqrestore(&vchan->vc.lock, flags);
921 
922 	vchan_dma_desc_free_list(&vchan->vc, &head);
923 
924 	return 0;
925 }
926 
927 static enum dma_status sun6i_dma_tx_status(struct dma_chan *chan,
928 					   dma_cookie_t cookie,
929 					   struct dma_tx_state *state)
930 {
931 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
932 	struct sun6i_pchan *pchan = vchan->phy;
933 	struct sun6i_dma_lli *lli;
934 	struct virt_dma_desc *vd;
935 	struct sun6i_desc *txd;
936 	enum dma_status ret;
937 	unsigned long flags;
938 	size_t bytes = 0;
939 
940 	ret = dma_cookie_status(chan, cookie, state);
941 	if (ret == DMA_COMPLETE || !state)
942 		return ret;
943 
944 	spin_lock_irqsave(&vchan->vc.lock, flags);
945 
946 	vd = vchan_find_desc(&vchan->vc, cookie);
947 	txd = to_sun6i_desc(&vd->tx);
948 
949 	if (vd) {
950 		for (lli = txd->v_lli; lli != NULL; lli = lli->v_lli_next)
951 			bytes += lli->len;
952 	} else if (!pchan || !pchan->desc) {
953 		bytes = 0;
954 	} else {
955 		bytes = sun6i_get_chan_size(pchan);
956 	}
957 
958 	spin_unlock_irqrestore(&vchan->vc.lock, flags);
959 
960 	dma_set_residue(state, bytes);
961 
962 	return ret;
963 }
964 
965 static void sun6i_dma_issue_pending(struct dma_chan *chan)
966 {
967 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
968 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
969 	unsigned long flags;
970 
971 	spin_lock_irqsave(&vchan->vc.lock, flags);
972 
973 	if (vchan_issue_pending(&vchan->vc)) {
974 		spin_lock(&sdev->lock);
975 
976 		if (!vchan->phy && list_empty(&vchan->node)) {
977 			list_add_tail(&vchan->node, &sdev->pending);
978 			tasklet_schedule(&sdev->task);
979 			dev_dbg(chan2dev(chan), "vchan %p: issued\n",
980 				&vchan->vc);
981 		}
982 
983 		spin_unlock(&sdev->lock);
984 	} else {
985 		dev_dbg(chan2dev(chan), "vchan %p: nothing to issue\n",
986 			&vchan->vc);
987 	}
988 
989 	spin_unlock_irqrestore(&vchan->vc.lock, flags);
990 }
991 
992 static void sun6i_dma_free_chan_resources(struct dma_chan *chan)
993 {
994 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
995 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
996 	unsigned long flags;
997 
998 	spin_lock_irqsave(&sdev->lock, flags);
999 	list_del_init(&vchan->node);
1000 	spin_unlock_irqrestore(&sdev->lock, flags);
1001 
1002 	vchan_free_chan_resources(&vchan->vc);
1003 }
1004 
1005 static struct dma_chan *sun6i_dma_of_xlate(struct of_phandle_args *dma_spec,
1006 					   struct of_dma *ofdma)
1007 {
1008 	struct sun6i_dma_dev *sdev = ofdma->of_dma_data;
1009 	struct sun6i_vchan *vchan;
1010 	struct dma_chan *chan;
1011 	u8 port = dma_spec->args[0];
1012 
1013 	if (port > sdev->max_request)
1014 		return NULL;
1015 
1016 	chan = dma_get_any_slave_channel(&sdev->slave);
1017 	if (!chan)
1018 		return NULL;
1019 
1020 	vchan = to_sun6i_vchan(chan);
1021 	vchan->port = port;
1022 
1023 	return chan;
1024 }
1025 
1026 static inline void sun6i_kill_tasklet(struct sun6i_dma_dev *sdev)
1027 {
1028 	/* Disable all interrupts from DMA */
1029 	writel(0, sdev->base + DMA_IRQ_EN(0));
1030 	writel(0, sdev->base + DMA_IRQ_EN(1));
1031 
1032 	/* Prevent spurious interrupts from scheduling the tasklet */
1033 	atomic_inc(&sdev->tasklet_shutdown);
1034 
1035 	/* Make sure we won't have any further interrupts */
1036 	devm_free_irq(sdev->slave.dev, sdev->irq, sdev);
1037 
1038 	/* Actually prevent the tasklet from being scheduled */
1039 	tasklet_kill(&sdev->task);
1040 }
1041 
1042 static inline void sun6i_dma_free(struct sun6i_dma_dev *sdev)
1043 {
1044 	int i;
1045 
1046 	for (i = 0; i < sdev->num_vchans; i++) {
1047 		struct sun6i_vchan *vchan = &sdev->vchans[i];
1048 
1049 		list_del(&vchan->vc.chan.device_node);
1050 		tasklet_kill(&vchan->vc.task);
1051 	}
1052 }
1053 
1054 /*
1055  * For A31:
1056  *
1057  * There's 16 physical channels that can work in parallel.
1058  *
1059  * However we have 30 different endpoints for our requests.
1060  *
1061  * Since the channels are able to handle only an unidirectional
1062  * transfer, we need to allocate more virtual channels so that
1063  * everyone can grab one channel.
1064  *
1065  * Some devices can't work in both direction (mostly because it
1066  * wouldn't make sense), so we have a bit fewer virtual channels than
1067  * 2 channels per endpoints.
1068  */
1069 
1070 static struct sun6i_dma_config sun6i_a31_dma_cfg = {
1071 	.nr_max_channels = 16,
1072 	.nr_max_requests = 30,
1073 	.nr_max_vchans   = 53,
1074 	.set_burst_length = sun6i_set_burst_length_a31,
1075 	.set_drq          = sun6i_set_drq_a31,
1076 	.set_mode         = sun6i_set_mode_a31,
1077 	.src_burst_lengths = BIT(1) | BIT(8),
1078 	.dst_burst_lengths = BIT(1) | BIT(8),
1079 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1080 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1081 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1082 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1083 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1084 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1085 };
1086 
1087 /*
1088  * The A23 only has 8 physical channels, a maximum DRQ port id of 24,
1089  * and a total of 37 usable source and destination endpoints.
1090  */
1091 
1092 static struct sun6i_dma_config sun8i_a23_dma_cfg = {
1093 	.nr_max_channels = 8,
1094 	.nr_max_requests = 24,
1095 	.nr_max_vchans   = 37,
1096 	.clock_autogate_enable = sun6i_enable_clock_autogate_a23,
1097 	.set_burst_length = sun6i_set_burst_length_a31,
1098 	.set_drq          = sun6i_set_drq_a31,
1099 	.set_mode         = sun6i_set_mode_a31,
1100 	.src_burst_lengths = BIT(1) | BIT(8),
1101 	.dst_burst_lengths = BIT(1) | BIT(8),
1102 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1103 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1104 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1105 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1106 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1107 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1108 };
1109 
1110 static struct sun6i_dma_config sun8i_a83t_dma_cfg = {
1111 	.nr_max_channels = 8,
1112 	.nr_max_requests = 28,
1113 	.nr_max_vchans   = 39,
1114 	.clock_autogate_enable = sun6i_enable_clock_autogate_a23,
1115 	.set_burst_length = sun6i_set_burst_length_a31,
1116 	.set_drq          = sun6i_set_drq_a31,
1117 	.set_mode         = sun6i_set_mode_a31,
1118 	.src_burst_lengths = BIT(1) | BIT(8),
1119 	.dst_burst_lengths = BIT(1) | BIT(8),
1120 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1121 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1122 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1123 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1124 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1125 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1126 };
1127 
1128 /*
1129  * The H3 has 12 physical channels, a maximum DRQ port id of 27,
1130  * and a total of 34 usable source and destination endpoints.
1131  * It also supports additional burst lengths and bus widths,
1132  * and the burst length fields have different offsets.
1133  */
1134 
1135 static struct sun6i_dma_config sun8i_h3_dma_cfg = {
1136 	.nr_max_channels = 12,
1137 	.nr_max_requests = 27,
1138 	.nr_max_vchans   = 34,
1139 	.clock_autogate_enable = sun6i_enable_clock_autogate_h3,
1140 	.set_burst_length = sun6i_set_burst_length_h3,
1141 	.set_drq          = sun6i_set_drq_a31,
1142 	.set_mode         = sun6i_set_mode_a31,
1143 	.src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1144 	.dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1145 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1146 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1147 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1148 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1149 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1150 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1151 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1152 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1153 };
1154 
1155 /*
1156  * The A64 binding uses the number of dma channels from the
1157  * device tree node.
1158  */
1159 static struct sun6i_dma_config sun50i_a64_dma_cfg = {
1160 	.clock_autogate_enable = sun6i_enable_clock_autogate_h3,
1161 	.set_burst_length = sun6i_set_burst_length_h3,
1162 	.set_drq          = sun6i_set_drq_a31,
1163 	.set_mode         = sun6i_set_mode_a31,
1164 	.src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1165 	.dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1166 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1167 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1168 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1169 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1170 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1171 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1172 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1173 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1174 };
1175 
1176 /*
1177  * TODO: Add support for more than 4g physical addressing.
1178  *
1179  * The A100 binding uses the number of dma channels from the
1180  * device tree node.
1181  */
1182 static struct sun6i_dma_config sun50i_a100_dma_cfg = {
1183 	.clock_autogate_enable = sun6i_enable_clock_autogate_h3,
1184 	.set_burst_length = sun6i_set_burst_length_h3,
1185 	.set_drq          = sun6i_set_drq_h6,
1186 	.set_mode         = sun6i_set_mode_h6,
1187 	.src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1188 	.dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1189 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1190 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1191 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1192 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1193 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1194 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1195 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1196 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1197 	.has_mbus_clk = true,
1198 };
1199 
1200 /*
1201  * The H6 binding uses the number of dma channels from the
1202  * device tree node.
1203  */
1204 static struct sun6i_dma_config sun50i_h6_dma_cfg = {
1205 	.clock_autogate_enable = sun6i_enable_clock_autogate_h3,
1206 	.set_burst_length = sun6i_set_burst_length_h3,
1207 	.set_drq          = sun6i_set_drq_h6,
1208 	.set_mode         = sun6i_set_mode_h6,
1209 	.src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1210 	.dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1211 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1212 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1213 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1214 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1215 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1216 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1217 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1218 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1219 	.has_mbus_clk = true,
1220 };
1221 
1222 /*
1223  * The V3s have only 8 physical channels, a maximum DRQ port id of 23,
1224  * and a total of 24 usable source and destination endpoints.
1225  */
1226 
1227 static struct sun6i_dma_config sun8i_v3s_dma_cfg = {
1228 	.nr_max_channels = 8,
1229 	.nr_max_requests = 23,
1230 	.nr_max_vchans   = 24,
1231 	.clock_autogate_enable = sun6i_enable_clock_autogate_a23,
1232 	.set_burst_length = sun6i_set_burst_length_a31,
1233 	.set_drq          = sun6i_set_drq_a31,
1234 	.set_mode         = sun6i_set_mode_a31,
1235 	.src_burst_lengths = BIT(1) | BIT(8),
1236 	.dst_burst_lengths = BIT(1) | BIT(8),
1237 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1238 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1239 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1240 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1241 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1242 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1243 };
1244 
1245 static const struct of_device_id sun6i_dma_match[] = {
1246 	{ .compatible = "allwinner,sun6i-a31-dma", .data = &sun6i_a31_dma_cfg },
1247 	{ .compatible = "allwinner,sun8i-a23-dma", .data = &sun8i_a23_dma_cfg },
1248 	{ .compatible = "allwinner,sun8i-a83t-dma", .data = &sun8i_a83t_dma_cfg },
1249 	{ .compatible = "allwinner,sun8i-h3-dma", .data = &sun8i_h3_dma_cfg },
1250 	{ .compatible = "allwinner,sun8i-v3s-dma", .data = &sun8i_v3s_dma_cfg },
1251 	{ .compatible = "allwinner,sun50i-a64-dma", .data = &sun50i_a64_dma_cfg },
1252 	{ .compatible = "allwinner,sun50i-a100-dma", .data = &sun50i_a100_dma_cfg },
1253 	{ .compatible = "allwinner,sun50i-h6-dma", .data = &sun50i_h6_dma_cfg },
1254 	{ /* sentinel */ }
1255 };
1256 MODULE_DEVICE_TABLE(of, sun6i_dma_match);
1257 
1258 static int sun6i_dma_probe(struct platform_device *pdev)
1259 {
1260 	struct device_node *np = pdev->dev.of_node;
1261 	struct sun6i_dma_dev *sdc;
1262 	struct resource *res;
1263 	int ret, i;
1264 
1265 	sdc = devm_kzalloc(&pdev->dev, sizeof(*sdc), GFP_KERNEL);
1266 	if (!sdc)
1267 		return -ENOMEM;
1268 
1269 	sdc->cfg = of_device_get_match_data(&pdev->dev);
1270 	if (!sdc->cfg)
1271 		return -ENODEV;
1272 
1273 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1274 	sdc->base = devm_ioremap_resource(&pdev->dev, res);
1275 	if (IS_ERR(sdc->base))
1276 		return PTR_ERR(sdc->base);
1277 
1278 	sdc->irq = platform_get_irq(pdev, 0);
1279 	if (sdc->irq < 0)
1280 		return sdc->irq;
1281 
1282 	sdc->clk = devm_clk_get(&pdev->dev, NULL);
1283 	if (IS_ERR(sdc->clk)) {
1284 		dev_err(&pdev->dev, "No clock specified\n");
1285 		return PTR_ERR(sdc->clk);
1286 	}
1287 
1288 	if (sdc->cfg->has_mbus_clk) {
1289 		sdc->clk_mbus = devm_clk_get(&pdev->dev, "mbus");
1290 		if (IS_ERR(sdc->clk_mbus)) {
1291 			dev_err(&pdev->dev, "No mbus clock specified\n");
1292 			return PTR_ERR(sdc->clk_mbus);
1293 		}
1294 	}
1295 
1296 	sdc->rstc = devm_reset_control_get(&pdev->dev, NULL);
1297 	if (IS_ERR(sdc->rstc)) {
1298 		dev_err(&pdev->dev, "No reset controller specified\n");
1299 		return PTR_ERR(sdc->rstc);
1300 	}
1301 
1302 	sdc->pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
1303 				     sizeof(struct sun6i_dma_lli), 4, 0);
1304 	if (!sdc->pool) {
1305 		dev_err(&pdev->dev, "No memory for descriptors dma pool\n");
1306 		return -ENOMEM;
1307 	}
1308 
1309 	platform_set_drvdata(pdev, sdc);
1310 	INIT_LIST_HEAD(&sdc->pending);
1311 	spin_lock_init(&sdc->lock);
1312 
1313 	dma_cap_set(DMA_PRIVATE, sdc->slave.cap_mask);
1314 	dma_cap_set(DMA_MEMCPY, sdc->slave.cap_mask);
1315 	dma_cap_set(DMA_SLAVE, sdc->slave.cap_mask);
1316 	dma_cap_set(DMA_CYCLIC, sdc->slave.cap_mask);
1317 
1318 	INIT_LIST_HEAD(&sdc->slave.channels);
1319 	sdc->slave.device_free_chan_resources	= sun6i_dma_free_chan_resources;
1320 	sdc->slave.device_tx_status		= sun6i_dma_tx_status;
1321 	sdc->slave.device_issue_pending		= sun6i_dma_issue_pending;
1322 	sdc->slave.device_prep_slave_sg		= sun6i_dma_prep_slave_sg;
1323 	sdc->slave.device_prep_dma_memcpy	= sun6i_dma_prep_dma_memcpy;
1324 	sdc->slave.device_prep_dma_cyclic	= sun6i_dma_prep_dma_cyclic;
1325 	sdc->slave.copy_align			= DMAENGINE_ALIGN_4_BYTES;
1326 	sdc->slave.device_config		= sun6i_dma_config;
1327 	sdc->slave.device_pause			= sun6i_dma_pause;
1328 	sdc->slave.device_resume		= sun6i_dma_resume;
1329 	sdc->slave.device_terminate_all		= sun6i_dma_terminate_all;
1330 	sdc->slave.src_addr_widths		= sdc->cfg->src_addr_widths;
1331 	sdc->slave.dst_addr_widths		= sdc->cfg->dst_addr_widths;
1332 	sdc->slave.directions			= BIT(DMA_DEV_TO_MEM) |
1333 						  BIT(DMA_MEM_TO_DEV);
1334 	sdc->slave.residue_granularity		= DMA_RESIDUE_GRANULARITY_BURST;
1335 	sdc->slave.dev = &pdev->dev;
1336 
1337 	sdc->num_pchans = sdc->cfg->nr_max_channels;
1338 	sdc->num_vchans = sdc->cfg->nr_max_vchans;
1339 	sdc->max_request = sdc->cfg->nr_max_requests;
1340 
1341 	ret = of_property_read_u32(np, "dma-channels", &sdc->num_pchans);
1342 	if (ret && !sdc->num_pchans) {
1343 		dev_err(&pdev->dev, "Can't get dma-channels.\n");
1344 		return ret;
1345 	}
1346 
1347 	ret = of_property_read_u32(np, "dma-requests", &sdc->max_request);
1348 	if (ret && !sdc->max_request) {
1349 		dev_info(&pdev->dev, "Missing dma-requests, using %u.\n",
1350 			 DMA_CHAN_MAX_DRQ_A31);
1351 		sdc->max_request = DMA_CHAN_MAX_DRQ_A31;
1352 	}
1353 
1354 	/*
1355 	 * If the number of vchans is not specified, derive it from the
1356 	 * highest port number, at most one channel per port and direction.
1357 	 */
1358 	if (!sdc->num_vchans)
1359 		sdc->num_vchans = 2 * (sdc->max_request + 1);
1360 
1361 	sdc->pchans = devm_kcalloc(&pdev->dev, sdc->num_pchans,
1362 				   sizeof(struct sun6i_pchan), GFP_KERNEL);
1363 	if (!sdc->pchans)
1364 		return -ENOMEM;
1365 
1366 	sdc->vchans = devm_kcalloc(&pdev->dev, sdc->num_vchans,
1367 				   sizeof(struct sun6i_vchan), GFP_KERNEL);
1368 	if (!sdc->vchans)
1369 		return -ENOMEM;
1370 
1371 	tasklet_setup(&sdc->task, sun6i_dma_tasklet);
1372 
1373 	for (i = 0; i < sdc->num_pchans; i++) {
1374 		struct sun6i_pchan *pchan = &sdc->pchans[i];
1375 
1376 		pchan->idx = i;
1377 		pchan->base = sdc->base + 0x100 + i * 0x40;
1378 	}
1379 
1380 	for (i = 0; i < sdc->num_vchans; i++) {
1381 		struct sun6i_vchan *vchan = &sdc->vchans[i];
1382 
1383 		INIT_LIST_HEAD(&vchan->node);
1384 		vchan->vc.desc_free = sun6i_dma_free_desc;
1385 		vchan_init(&vchan->vc, &sdc->slave);
1386 	}
1387 
1388 	ret = reset_control_deassert(sdc->rstc);
1389 	if (ret) {
1390 		dev_err(&pdev->dev, "Couldn't deassert the device from reset\n");
1391 		goto err_chan_free;
1392 	}
1393 
1394 	ret = clk_prepare_enable(sdc->clk);
1395 	if (ret) {
1396 		dev_err(&pdev->dev, "Couldn't enable the clock\n");
1397 		goto err_reset_assert;
1398 	}
1399 
1400 	if (sdc->cfg->has_mbus_clk) {
1401 		ret = clk_prepare_enable(sdc->clk_mbus);
1402 		if (ret) {
1403 			dev_err(&pdev->dev, "Couldn't enable mbus clock\n");
1404 			goto err_clk_disable;
1405 		}
1406 	}
1407 
1408 	ret = devm_request_irq(&pdev->dev, sdc->irq, sun6i_dma_interrupt, 0,
1409 			       dev_name(&pdev->dev), sdc);
1410 	if (ret) {
1411 		dev_err(&pdev->dev, "Cannot request IRQ\n");
1412 		goto err_mbus_clk_disable;
1413 	}
1414 
1415 	ret = dma_async_device_register(&sdc->slave);
1416 	if (ret) {
1417 		dev_warn(&pdev->dev, "Failed to register DMA engine device\n");
1418 		goto err_irq_disable;
1419 	}
1420 
1421 	ret = of_dma_controller_register(pdev->dev.of_node, sun6i_dma_of_xlate,
1422 					 sdc);
1423 	if (ret) {
1424 		dev_err(&pdev->dev, "of_dma_controller_register failed\n");
1425 		goto err_dma_unregister;
1426 	}
1427 
1428 	if (sdc->cfg->clock_autogate_enable)
1429 		sdc->cfg->clock_autogate_enable(sdc);
1430 
1431 	return 0;
1432 
1433 err_dma_unregister:
1434 	dma_async_device_unregister(&sdc->slave);
1435 err_irq_disable:
1436 	sun6i_kill_tasklet(sdc);
1437 err_mbus_clk_disable:
1438 	clk_disable_unprepare(sdc->clk_mbus);
1439 err_clk_disable:
1440 	clk_disable_unprepare(sdc->clk);
1441 err_reset_assert:
1442 	reset_control_assert(sdc->rstc);
1443 err_chan_free:
1444 	sun6i_dma_free(sdc);
1445 	return ret;
1446 }
1447 
1448 static int sun6i_dma_remove(struct platform_device *pdev)
1449 {
1450 	struct sun6i_dma_dev *sdc = platform_get_drvdata(pdev);
1451 
1452 	of_dma_controller_free(pdev->dev.of_node);
1453 	dma_async_device_unregister(&sdc->slave);
1454 
1455 	sun6i_kill_tasklet(sdc);
1456 
1457 	clk_disable_unprepare(sdc->clk_mbus);
1458 	clk_disable_unprepare(sdc->clk);
1459 	reset_control_assert(sdc->rstc);
1460 
1461 	sun6i_dma_free(sdc);
1462 
1463 	return 0;
1464 }
1465 
1466 static struct platform_driver sun6i_dma_driver = {
1467 	.probe		= sun6i_dma_probe,
1468 	.remove		= sun6i_dma_remove,
1469 	.driver = {
1470 		.name		= "sun6i-dma",
1471 		.of_match_table	= sun6i_dma_match,
1472 	},
1473 };
1474 module_platform_driver(sun6i_dma_driver);
1475 
1476 MODULE_DESCRIPTION("Allwinner A31 DMA Controller Driver");
1477 MODULE_AUTHOR("Sugar <shuge@allwinnertech.com>");
1478 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1479 MODULE_LICENSE("GPL");
1480