xref: /openbmc/linux/drivers/dma/sun6i-dma.c (revision bbecb07f)
1 /*
2  * Copyright (C) 2013-2014 Allwinner Tech Co., Ltd
3  * Author: Sugar <shuge@allwinnertech.com>
4  *
5  * Copyright (C) 2014 Maxime Ripard
6  * Maxime Ripard <maxime.ripard@free-electrons.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/dmaengine.h>
17 #include <linux/dmapool.h>
18 #include <linux/interrupt.h>
19 #include <linux/module.h>
20 #include <linux/of_dma.h>
21 #include <linux/of_device.h>
22 #include <linux/platform_device.h>
23 #include <linux/reset.h>
24 #include <linux/slab.h>
25 #include <linux/types.h>
26 
27 #include "virt-dma.h"
28 
29 /*
30  * Common registers
31  */
32 #define DMA_IRQ_EN(x)		((x) * 0x04)
33 #define DMA_IRQ_HALF			BIT(0)
34 #define DMA_IRQ_PKG			BIT(1)
35 #define DMA_IRQ_QUEUE			BIT(2)
36 
37 #define DMA_IRQ_CHAN_NR			8
38 #define DMA_IRQ_CHAN_WIDTH		4
39 
40 
41 #define DMA_IRQ_STAT(x)		((x) * 0x04 + 0x10)
42 
43 #define DMA_STAT		0x30
44 
45 /* Offset between DMA_IRQ_EN and DMA_IRQ_STAT limits number of channels */
46 #define DMA_MAX_CHANNELS	(DMA_IRQ_CHAN_NR * 0x10 / 4)
47 
48 /*
49  * sun8i specific registers
50  */
51 #define SUN8I_DMA_GATE		0x20
52 #define SUN8I_DMA_GATE_ENABLE	0x4
53 
54 #define SUNXI_H3_SECURE_REG		0x20
55 #define SUNXI_H3_DMA_GATE		0x28
56 #define SUNXI_H3_DMA_GATE_ENABLE	0x4
57 /*
58  * Channels specific registers
59  */
60 #define DMA_CHAN_ENABLE		0x00
61 #define DMA_CHAN_ENABLE_START		BIT(0)
62 #define DMA_CHAN_ENABLE_STOP		0
63 
64 #define DMA_CHAN_PAUSE		0x04
65 #define DMA_CHAN_PAUSE_PAUSE		BIT(1)
66 #define DMA_CHAN_PAUSE_RESUME		0
67 
68 #define DMA_CHAN_LLI_ADDR	0x08
69 
70 #define DMA_CHAN_CUR_CFG	0x0c
71 #define DMA_CHAN_MAX_DRQ		0x1f
72 #define DMA_CHAN_CFG_SRC_DRQ(x)		((x) & DMA_CHAN_MAX_DRQ)
73 #define DMA_CHAN_CFG_SRC_IO_MODE	BIT(5)
74 #define DMA_CHAN_CFG_SRC_LINEAR_MODE	(0 << 5)
75 #define DMA_CHAN_CFG_SRC_BURST_A31(x)	(((x) & 0x3) << 7)
76 #define DMA_CHAN_CFG_SRC_BURST_H3(x)	(((x) & 0x3) << 6)
77 #define DMA_CHAN_CFG_SRC_WIDTH(x)	(((x) & 0x3) << 9)
78 
79 #define DMA_CHAN_CFG_DST_DRQ(x)		(DMA_CHAN_CFG_SRC_DRQ(x) << 16)
80 #define DMA_CHAN_CFG_DST_IO_MODE	(DMA_CHAN_CFG_SRC_IO_MODE << 16)
81 #define DMA_CHAN_CFG_DST_LINEAR_MODE	(DMA_CHAN_CFG_SRC_LINEAR_MODE << 16)
82 #define DMA_CHAN_CFG_DST_BURST_A31(x)	(DMA_CHAN_CFG_SRC_BURST_A31(x) << 16)
83 #define DMA_CHAN_CFG_DST_BURST_H3(x)	(DMA_CHAN_CFG_SRC_BURST_H3(x) << 16)
84 #define DMA_CHAN_CFG_DST_WIDTH(x)	(DMA_CHAN_CFG_SRC_WIDTH(x) << 16)
85 
86 #define DMA_CHAN_CUR_SRC	0x10
87 
88 #define DMA_CHAN_CUR_DST	0x14
89 
90 #define DMA_CHAN_CUR_CNT	0x18
91 
92 #define DMA_CHAN_CUR_PARA	0x1c
93 
94 
95 /*
96  * Various hardware related defines
97  */
98 #define LLI_LAST_ITEM	0xfffff800
99 #define NORMAL_WAIT	8
100 #define DRQ_SDRAM	1
101 
102 /* forward declaration */
103 struct sun6i_dma_dev;
104 
105 /*
106  * Hardware channels / ports representation
107  *
108  * The hardware is used in several SoCs, with differing numbers
109  * of channels and endpoints. This structure ties those numbers
110  * to a certain compatible string.
111  */
112 struct sun6i_dma_config {
113 	u32 nr_max_channels;
114 	u32 nr_max_requests;
115 	u32 nr_max_vchans;
116 	/*
117 	 * In the datasheets/user manuals of newer Allwinner SoCs, a special
118 	 * bit (bit 2 at register 0x20) is present.
119 	 * It's named "DMA MCLK interface circuit auto gating bit" in the
120 	 * documents, and the footnote of this register says that this bit
121 	 * should be set up when initializing the DMA controller.
122 	 * Allwinner A23/A33 user manuals do not have this bit documented,
123 	 * however these SoCs really have and need this bit, as seen in the
124 	 * BSP kernel source code.
125 	 */
126 	void (*clock_autogate_enable)(struct sun6i_dma_dev *);
127 	void (*set_burst_length)(u32 *p_cfg, s8 src_burst, s8 dst_burst);
128 	u32 src_burst_lengths;
129 	u32 dst_burst_lengths;
130 	u32 src_addr_widths;
131 	u32 dst_addr_widths;
132 };
133 
134 /*
135  * Hardware representation of the LLI
136  *
137  * The hardware will be fed the physical address of this structure,
138  * and read its content in order to start the transfer.
139  */
140 struct sun6i_dma_lli {
141 	u32			cfg;
142 	u32			src;
143 	u32			dst;
144 	u32			len;
145 	u32			para;
146 	u32			p_lli_next;
147 
148 	/*
149 	 * This field is not used by the DMA controller, but will be
150 	 * used by the CPU to go through the list (mostly for dumping
151 	 * or freeing it).
152 	 */
153 	struct sun6i_dma_lli	*v_lli_next;
154 };
155 
156 
157 struct sun6i_desc {
158 	struct virt_dma_desc	vd;
159 	dma_addr_t		p_lli;
160 	struct sun6i_dma_lli	*v_lli;
161 };
162 
163 struct sun6i_pchan {
164 	u32			idx;
165 	void __iomem		*base;
166 	struct sun6i_vchan	*vchan;
167 	struct sun6i_desc	*desc;
168 	struct sun6i_desc	*done;
169 };
170 
171 struct sun6i_vchan {
172 	struct virt_dma_chan	vc;
173 	struct list_head	node;
174 	struct dma_slave_config	cfg;
175 	struct sun6i_pchan	*phy;
176 	u8			port;
177 	u8			irq_type;
178 	bool			cyclic;
179 };
180 
181 struct sun6i_dma_dev {
182 	struct dma_device	slave;
183 	void __iomem		*base;
184 	struct clk		*clk;
185 	int			irq;
186 	spinlock_t		lock;
187 	struct reset_control	*rstc;
188 	struct tasklet_struct	task;
189 	atomic_t		tasklet_shutdown;
190 	struct list_head	pending;
191 	struct dma_pool		*pool;
192 	struct sun6i_pchan	*pchans;
193 	struct sun6i_vchan	*vchans;
194 	const struct sun6i_dma_config *cfg;
195 	u32			num_pchans;
196 	u32			num_vchans;
197 	u32			max_request;
198 };
199 
200 static struct device *chan2dev(struct dma_chan *chan)
201 {
202 	return &chan->dev->device;
203 }
204 
205 static inline struct sun6i_dma_dev *to_sun6i_dma_dev(struct dma_device *d)
206 {
207 	return container_of(d, struct sun6i_dma_dev, slave);
208 }
209 
210 static inline struct sun6i_vchan *to_sun6i_vchan(struct dma_chan *chan)
211 {
212 	return container_of(chan, struct sun6i_vchan, vc.chan);
213 }
214 
215 static inline struct sun6i_desc *
216 to_sun6i_desc(struct dma_async_tx_descriptor *tx)
217 {
218 	return container_of(tx, struct sun6i_desc, vd.tx);
219 }
220 
221 static inline void sun6i_dma_dump_com_regs(struct sun6i_dma_dev *sdev)
222 {
223 	dev_dbg(sdev->slave.dev, "Common register:\n"
224 		"\tmask0(%04x): 0x%08x\n"
225 		"\tmask1(%04x): 0x%08x\n"
226 		"\tpend0(%04x): 0x%08x\n"
227 		"\tpend1(%04x): 0x%08x\n"
228 		"\tstats(%04x): 0x%08x\n",
229 		DMA_IRQ_EN(0), readl(sdev->base + DMA_IRQ_EN(0)),
230 		DMA_IRQ_EN(1), readl(sdev->base + DMA_IRQ_EN(1)),
231 		DMA_IRQ_STAT(0), readl(sdev->base + DMA_IRQ_STAT(0)),
232 		DMA_IRQ_STAT(1), readl(sdev->base + DMA_IRQ_STAT(1)),
233 		DMA_STAT, readl(sdev->base + DMA_STAT));
234 }
235 
236 static inline void sun6i_dma_dump_chan_regs(struct sun6i_dma_dev *sdev,
237 					    struct sun6i_pchan *pchan)
238 {
239 	phys_addr_t reg = virt_to_phys(pchan->base);
240 
241 	dev_dbg(sdev->slave.dev, "Chan %d reg: %pa\n"
242 		"\t___en(%04x): \t0x%08x\n"
243 		"\tpause(%04x): \t0x%08x\n"
244 		"\tstart(%04x): \t0x%08x\n"
245 		"\t__cfg(%04x): \t0x%08x\n"
246 		"\t__src(%04x): \t0x%08x\n"
247 		"\t__dst(%04x): \t0x%08x\n"
248 		"\tcount(%04x): \t0x%08x\n"
249 		"\t_para(%04x): \t0x%08x\n\n",
250 		pchan->idx, &reg,
251 		DMA_CHAN_ENABLE,
252 		readl(pchan->base + DMA_CHAN_ENABLE),
253 		DMA_CHAN_PAUSE,
254 		readl(pchan->base + DMA_CHAN_PAUSE),
255 		DMA_CHAN_LLI_ADDR,
256 		readl(pchan->base + DMA_CHAN_LLI_ADDR),
257 		DMA_CHAN_CUR_CFG,
258 		readl(pchan->base + DMA_CHAN_CUR_CFG),
259 		DMA_CHAN_CUR_SRC,
260 		readl(pchan->base + DMA_CHAN_CUR_SRC),
261 		DMA_CHAN_CUR_DST,
262 		readl(pchan->base + DMA_CHAN_CUR_DST),
263 		DMA_CHAN_CUR_CNT,
264 		readl(pchan->base + DMA_CHAN_CUR_CNT),
265 		DMA_CHAN_CUR_PARA,
266 		readl(pchan->base + DMA_CHAN_CUR_PARA));
267 }
268 
269 static inline s8 convert_burst(u32 maxburst)
270 {
271 	switch (maxburst) {
272 	case 1:
273 		return 0;
274 	case 4:
275 		return 1;
276 	case 8:
277 		return 2;
278 	case 16:
279 		return 3;
280 	default:
281 		return -EINVAL;
282 	}
283 }
284 
285 static inline s8 convert_buswidth(enum dma_slave_buswidth addr_width)
286 {
287 	return ilog2(addr_width);
288 }
289 
290 static void sun6i_enable_clock_autogate_a23(struct sun6i_dma_dev *sdev)
291 {
292 	writel(SUN8I_DMA_GATE_ENABLE, sdev->base + SUN8I_DMA_GATE);
293 }
294 
295 static void sun6i_enable_clock_autogate_h3(struct sun6i_dma_dev *sdev)
296 {
297 	writel(SUNXI_H3_DMA_GATE_ENABLE, sdev->base + SUNXI_H3_DMA_GATE);
298 }
299 
300 static void sun6i_set_burst_length_a31(u32 *p_cfg, s8 src_burst, s8 dst_burst)
301 {
302 	*p_cfg |= DMA_CHAN_CFG_SRC_BURST_A31(src_burst) |
303 		  DMA_CHAN_CFG_DST_BURST_A31(dst_burst);
304 }
305 
306 static void sun6i_set_burst_length_h3(u32 *p_cfg, s8 src_burst, s8 dst_burst)
307 {
308 	*p_cfg |= DMA_CHAN_CFG_SRC_BURST_H3(src_burst) |
309 		  DMA_CHAN_CFG_DST_BURST_H3(dst_burst);
310 }
311 
312 static size_t sun6i_get_chan_size(struct sun6i_pchan *pchan)
313 {
314 	struct sun6i_desc *txd = pchan->desc;
315 	struct sun6i_dma_lli *lli;
316 	size_t bytes;
317 	dma_addr_t pos;
318 
319 	pos = readl(pchan->base + DMA_CHAN_LLI_ADDR);
320 	bytes = readl(pchan->base + DMA_CHAN_CUR_CNT);
321 
322 	if (pos == LLI_LAST_ITEM)
323 		return bytes;
324 
325 	for (lli = txd->v_lli; lli; lli = lli->v_lli_next) {
326 		if (lli->p_lli_next == pos) {
327 			for (lli = lli->v_lli_next; lli; lli = lli->v_lli_next)
328 				bytes += lli->len;
329 			break;
330 		}
331 	}
332 
333 	return bytes;
334 }
335 
336 static void *sun6i_dma_lli_add(struct sun6i_dma_lli *prev,
337 			       struct sun6i_dma_lli *next,
338 			       dma_addr_t next_phy,
339 			       struct sun6i_desc *txd)
340 {
341 	if ((!prev && !txd) || !next)
342 		return NULL;
343 
344 	if (!prev) {
345 		txd->p_lli = next_phy;
346 		txd->v_lli = next;
347 	} else {
348 		prev->p_lli_next = next_phy;
349 		prev->v_lli_next = next;
350 	}
351 
352 	next->p_lli_next = LLI_LAST_ITEM;
353 	next->v_lli_next = NULL;
354 
355 	return next;
356 }
357 
358 static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan,
359 				      struct sun6i_dma_lli *lli)
360 {
361 	phys_addr_t p_lli = virt_to_phys(lli);
362 
363 	dev_dbg(chan2dev(&vchan->vc.chan),
364 		"\n\tdesc:   p - %pa v - 0x%p\n"
365 		"\t\tc - 0x%08x s - 0x%08x d - 0x%08x\n"
366 		"\t\tl - 0x%08x p - 0x%08x n - 0x%08x\n",
367 		&p_lli, lli,
368 		lli->cfg, lli->src, lli->dst,
369 		lli->len, lli->para, lli->p_lli_next);
370 }
371 
372 static void sun6i_dma_free_desc(struct virt_dma_desc *vd)
373 {
374 	struct sun6i_desc *txd = to_sun6i_desc(&vd->tx);
375 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device);
376 	struct sun6i_dma_lli *v_lli, *v_next;
377 	dma_addr_t p_lli, p_next;
378 
379 	if (unlikely(!txd))
380 		return;
381 
382 	p_lli = txd->p_lli;
383 	v_lli = txd->v_lli;
384 
385 	while (v_lli) {
386 		v_next = v_lli->v_lli_next;
387 		p_next = v_lli->p_lli_next;
388 
389 		dma_pool_free(sdev->pool, v_lli, p_lli);
390 
391 		v_lli = v_next;
392 		p_lli = p_next;
393 	}
394 
395 	kfree(txd);
396 }
397 
398 static int sun6i_dma_start_desc(struct sun6i_vchan *vchan)
399 {
400 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device);
401 	struct virt_dma_desc *desc = vchan_next_desc(&vchan->vc);
402 	struct sun6i_pchan *pchan = vchan->phy;
403 	u32 irq_val, irq_reg, irq_offset;
404 
405 	if (!pchan)
406 		return -EAGAIN;
407 
408 	if (!desc) {
409 		pchan->desc = NULL;
410 		pchan->done = NULL;
411 		return -EAGAIN;
412 	}
413 
414 	list_del(&desc->node);
415 
416 	pchan->desc = to_sun6i_desc(&desc->tx);
417 	pchan->done = NULL;
418 
419 	sun6i_dma_dump_lli(vchan, pchan->desc->v_lli);
420 
421 	irq_reg = pchan->idx / DMA_IRQ_CHAN_NR;
422 	irq_offset = pchan->idx % DMA_IRQ_CHAN_NR;
423 
424 	vchan->irq_type = vchan->cyclic ? DMA_IRQ_PKG : DMA_IRQ_QUEUE;
425 
426 	irq_val = readl(sdev->base + DMA_IRQ_EN(irq_reg));
427 	irq_val &= ~((DMA_IRQ_HALF | DMA_IRQ_PKG | DMA_IRQ_QUEUE) <<
428 			(irq_offset * DMA_IRQ_CHAN_WIDTH));
429 	irq_val |= vchan->irq_type << (irq_offset * DMA_IRQ_CHAN_WIDTH);
430 	writel(irq_val, sdev->base + DMA_IRQ_EN(irq_reg));
431 
432 	writel(pchan->desc->p_lli, pchan->base + DMA_CHAN_LLI_ADDR);
433 	writel(DMA_CHAN_ENABLE_START, pchan->base + DMA_CHAN_ENABLE);
434 
435 	sun6i_dma_dump_com_regs(sdev);
436 	sun6i_dma_dump_chan_regs(sdev, pchan);
437 
438 	return 0;
439 }
440 
441 static void sun6i_dma_tasklet(unsigned long data)
442 {
443 	struct sun6i_dma_dev *sdev = (struct sun6i_dma_dev *)data;
444 	struct sun6i_vchan *vchan;
445 	struct sun6i_pchan *pchan;
446 	unsigned int pchan_alloc = 0;
447 	unsigned int pchan_idx;
448 
449 	list_for_each_entry(vchan, &sdev->slave.channels, vc.chan.device_node) {
450 		spin_lock_irq(&vchan->vc.lock);
451 
452 		pchan = vchan->phy;
453 
454 		if (pchan && pchan->done) {
455 			if (sun6i_dma_start_desc(vchan)) {
456 				/*
457 				 * No current txd associated with this channel
458 				 */
459 				dev_dbg(sdev->slave.dev, "pchan %u: free\n",
460 					pchan->idx);
461 
462 				/* Mark this channel free */
463 				vchan->phy = NULL;
464 				pchan->vchan = NULL;
465 			}
466 		}
467 		spin_unlock_irq(&vchan->vc.lock);
468 	}
469 
470 	spin_lock_irq(&sdev->lock);
471 	for (pchan_idx = 0; pchan_idx < sdev->num_pchans; pchan_idx++) {
472 		pchan = &sdev->pchans[pchan_idx];
473 
474 		if (pchan->vchan || list_empty(&sdev->pending))
475 			continue;
476 
477 		vchan = list_first_entry(&sdev->pending,
478 					 struct sun6i_vchan, node);
479 
480 		/* Remove from pending channels */
481 		list_del_init(&vchan->node);
482 		pchan_alloc |= BIT(pchan_idx);
483 
484 		/* Mark this channel allocated */
485 		pchan->vchan = vchan;
486 		vchan->phy = pchan;
487 		dev_dbg(sdev->slave.dev, "pchan %u: alloc vchan %p\n",
488 			pchan->idx, &vchan->vc);
489 	}
490 	spin_unlock_irq(&sdev->lock);
491 
492 	for (pchan_idx = 0; pchan_idx < sdev->num_pchans; pchan_idx++) {
493 		if (!(pchan_alloc & BIT(pchan_idx)))
494 			continue;
495 
496 		pchan = sdev->pchans + pchan_idx;
497 		vchan = pchan->vchan;
498 		if (vchan) {
499 			spin_lock_irq(&vchan->vc.lock);
500 			sun6i_dma_start_desc(vchan);
501 			spin_unlock_irq(&vchan->vc.lock);
502 		}
503 	}
504 }
505 
506 static irqreturn_t sun6i_dma_interrupt(int irq, void *dev_id)
507 {
508 	struct sun6i_dma_dev *sdev = dev_id;
509 	struct sun6i_vchan *vchan;
510 	struct sun6i_pchan *pchan;
511 	int i, j, ret = IRQ_NONE;
512 	u32 status;
513 
514 	for (i = 0; i < sdev->num_pchans / DMA_IRQ_CHAN_NR; i++) {
515 		status = readl(sdev->base + DMA_IRQ_STAT(i));
516 		if (!status)
517 			continue;
518 
519 		dev_dbg(sdev->slave.dev, "DMA irq status %s: 0x%x\n",
520 			i ? "high" : "low", status);
521 
522 		writel(status, sdev->base + DMA_IRQ_STAT(i));
523 
524 		for (j = 0; (j < DMA_IRQ_CHAN_NR) && status; j++) {
525 			pchan = sdev->pchans + j;
526 			vchan = pchan->vchan;
527 			if (vchan && (status & vchan->irq_type)) {
528 				if (vchan->cyclic) {
529 					vchan_cyclic_callback(&pchan->desc->vd);
530 				} else {
531 					spin_lock(&vchan->vc.lock);
532 					vchan_cookie_complete(&pchan->desc->vd);
533 					pchan->done = pchan->desc;
534 					spin_unlock(&vchan->vc.lock);
535 				}
536 			}
537 
538 			status = status >> DMA_IRQ_CHAN_WIDTH;
539 		}
540 
541 		if (!atomic_read(&sdev->tasklet_shutdown))
542 			tasklet_schedule(&sdev->task);
543 		ret = IRQ_HANDLED;
544 	}
545 
546 	return ret;
547 }
548 
549 static int set_config(struct sun6i_dma_dev *sdev,
550 			struct dma_slave_config *sconfig,
551 			enum dma_transfer_direction direction,
552 			u32 *p_cfg)
553 {
554 	enum dma_slave_buswidth src_addr_width, dst_addr_width;
555 	u32 src_maxburst, dst_maxburst;
556 	s8 src_width, dst_width, src_burst, dst_burst;
557 
558 	src_addr_width = sconfig->src_addr_width;
559 	dst_addr_width = sconfig->dst_addr_width;
560 	src_maxburst = sconfig->src_maxburst;
561 	dst_maxburst = sconfig->dst_maxburst;
562 
563 	switch (direction) {
564 	case DMA_MEM_TO_DEV:
565 		if (src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
566 			src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
567 		src_maxburst = src_maxburst ? src_maxburst : 8;
568 		break;
569 	case DMA_DEV_TO_MEM:
570 		if (dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
571 			dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
572 		dst_maxburst = dst_maxburst ? dst_maxburst : 8;
573 		break;
574 	default:
575 		return -EINVAL;
576 	}
577 
578 	if (!(BIT(src_addr_width) & sdev->slave.src_addr_widths))
579 		return -EINVAL;
580 	if (!(BIT(dst_addr_width) & sdev->slave.dst_addr_widths))
581 		return -EINVAL;
582 	if (!(BIT(src_maxburst) & sdev->cfg->src_burst_lengths))
583 		return -EINVAL;
584 	if (!(BIT(dst_maxburst) & sdev->cfg->dst_burst_lengths))
585 		return -EINVAL;
586 
587 	src_width = convert_buswidth(src_addr_width);
588 	dst_width = convert_buswidth(dst_addr_width);
589 	dst_burst = convert_burst(dst_maxburst);
590 	src_burst = convert_burst(src_maxburst);
591 
592 	*p_cfg = DMA_CHAN_CFG_SRC_WIDTH(src_width) |
593 		DMA_CHAN_CFG_DST_WIDTH(dst_width);
594 
595 	sdev->cfg->set_burst_length(p_cfg, src_burst, dst_burst);
596 
597 	return 0;
598 }
599 
600 static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_memcpy(
601 		struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
602 		size_t len, unsigned long flags)
603 {
604 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
605 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
606 	struct sun6i_dma_lli *v_lli;
607 	struct sun6i_desc *txd;
608 	dma_addr_t p_lli;
609 	s8 burst, width;
610 
611 	dev_dbg(chan2dev(chan),
612 		"%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n",
613 		__func__, vchan->vc.chan.chan_id, &dest, &src, len, flags);
614 
615 	if (!len)
616 		return NULL;
617 
618 	txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
619 	if (!txd)
620 		return NULL;
621 
622 	v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
623 	if (!v_lli) {
624 		dev_err(sdev->slave.dev, "Failed to alloc lli memory\n");
625 		goto err_txd_free;
626 	}
627 
628 	v_lli->src = src;
629 	v_lli->dst = dest;
630 	v_lli->len = len;
631 	v_lli->para = NORMAL_WAIT;
632 
633 	burst = convert_burst(8);
634 	width = convert_buswidth(DMA_SLAVE_BUSWIDTH_4_BYTES);
635 	v_lli->cfg = DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) |
636 		DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) |
637 		DMA_CHAN_CFG_DST_LINEAR_MODE |
638 		DMA_CHAN_CFG_SRC_LINEAR_MODE |
639 		DMA_CHAN_CFG_SRC_WIDTH(width) |
640 		DMA_CHAN_CFG_DST_WIDTH(width);
641 
642 	sdev->cfg->set_burst_length(&v_lli->cfg, burst, burst);
643 
644 	sun6i_dma_lli_add(NULL, v_lli, p_lli, txd);
645 
646 	sun6i_dma_dump_lli(vchan, v_lli);
647 
648 	return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
649 
650 err_txd_free:
651 	kfree(txd);
652 	return NULL;
653 }
654 
655 static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg(
656 		struct dma_chan *chan, struct scatterlist *sgl,
657 		unsigned int sg_len, enum dma_transfer_direction dir,
658 		unsigned long flags, void *context)
659 {
660 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
661 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
662 	struct dma_slave_config *sconfig = &vchan->cfg;
663 	struct sun6i_dma_lli *v_lli, *prev = NULL;
664 	struct sun6i_desc *txd;
665 	struct scatterlist *sg;
666 	dma_addr_t p_lli;
667 	u32 lli_cfg;
668 	int i, ret;
669 
670 	if (!sgl)
671 		return NULL;
672 
673 	ret = set_config(sdev, sconfig, dir, &lli_cfg);
674 	if (ret) {
675 		dev_err(chan2dev(chan), "Invalid DMA configuration\n");
676 		return NULL;
677 	}
678 
679 	txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
680 	if (!txd)
681 		return NULL;
682 
683 	for_each_sg(sgl, sg, sg_len, i) {
684 		v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
685 		if (!v_lli)
686 			goto err_lli_free;
687 
688 		v_lli->len = sg_dma_len(sg);
689 		v_lli->para = NORMAL_WAIT;
690 
691 		if (dir == DMA_MEM_TO_DEV) {
692 			v_lli->src = sg_dma_address(sg);
693 			v_lli->dst = sconfig->dst_addr;
694 			v_lli->cfg = lli_cfg |
695 				DMA_CHAN_CFG_DST_IO_MODE |
696 				DMA_CHAN_CFG_SRC_LINEAR_MODE |
697 				DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) |
698 				DMA_CHAN_CFG_DST_DRQ(vchan->port);
699 
700 			dev_dbg(chan2dev(chan),
701 				"%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n",
702 				__func__, vchan->vc.chan.chan_id,
703 				&sconfig->dst_addr, &sg_dma_address(sg),
704 				sg_dma_len(sg), flags);
705 
706 		} else {
707 			v_lli->src = sconfig->src_addr;
708 			v_lli->dst = sg_dma_address(sg);
709 			v_lli->cfg = lli_cfg |
710 				DMA_CHAN_CFG_DST_LINEAR_MODE |
711 				DMA_CHAN_CFG_SRC_IO_MODE |
712 				DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) |
713 				DMA_CHAN_CFG_SRC_DRQ(vchan->port);
714 
715 			dev_dbg(chan2dev(chan),
716 				"%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n",
717 				__func__, vchan->vc.chan.chan_id,
718 				&sg_dma_address(sg), &sconfig->src_addr,
719 				sg_dma_len(sg), flags);
720 		}
721 
722 		prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd);
723 	}
724 
725 	dev_dbg(chan2dev(chan), "First: %pad\n", &txd->p_lli);
726 	for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
727 		sun6i_dma_dump_lli(vchan, prev);
728 
729 	return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
730 
731 err_lli_free:
732 	for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
733 		dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
734 	kfree(txd);
735 	return NULL;
736 }
737 
738 static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_cyclic(
739 					struct dma_chan *chan,
740 					dma_addr_t buf_addr,
741 					size_t buf_len,
742 					size_t period_len,
743 					enum dma_transfer_direction dir,
744 					unsigned long flags)
745 {
746 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
747 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
748 	struct dma_slave_config *sconfig = &vchan->cfg;
749 	struct sun6i_dma_lli *v_lli, *prev = NULL;
750 	struct sun6i_desc *txd;
751 	dma_addr_t p_lli;
752 	u32 lli_cfg;
753 	unsigned int i, periods = buf_len / period_len;
754 	int ret;
755 
756 	ret = set_config(sdev, sconfig, dir, &lli_cfg);
757 	if (ret) {
758 		dev_err(chan2dev(chan), "Invalid DMA configuration\n");
759 		return NULL;
760 	}
761 
762 	txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
763 	if (!txd)
764 		return NULL;
765 
766 	for (i = 0; i < periods; i++) {
767 		v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
768 		if (!v_lli) {
769 			dev_err(sdev->slave.dev, "Failed to alloc lli memory\n");
770 			goto err_lli_free;
771 		}
772 
773 		v_lli->len = period_len;
774 		v_lli->para = NORMAL_WAIT;
775 
776 		if (dir == DMA_MEM_TO_DEV) {
777 			v_lli->src = buf_addr + period_len * i;
778 			v_lli->dst = sconfig->dst_addr;
779 			v_lli->cfg = lli_cfg |
780 				DMA_CHAN_CFG_DST_IO_MODE |
781 				DMA_CHAN_CFG_SRC_LINEAR_MODE |
782 				DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) |
783 				DMA_CHAN_CFG_DST_DRQ(vchan->port);
784 		} else {
785 			v_lli->src = sconfig->src_addr;
786 			v_lli->dst = buf_addr + period_len * i;
787 			v_lli->cfg = lli_cfg |
788 				DMA_CHAN_CFG_DST_LINEAR_MODE |
789 				DMA_CHAN_CFG_SRC_IO_MODE |
790 				DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) |
791 				DMA_CHAN_CFG_SRC_DRQ(vchan->port);
792 		}
793 
794 		prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd);
795 	}
796 
797 	prev->p_lli_next = txd->p_lli;		/* cyclic list */
798 
799 	vchan->cyclic = true;
800 
801 	return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
802 
803 err_lli_free:
804 	for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
805 		dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
806 	kfree(txd);
807 	return NULL;
808 }
809 
810 static int sun6i_dma_config(struct dma_chan *chan,
811 			    struct dma_slave_config *config)
812 {
813 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
814 
815 	memcpy(&vchan->cfg, config, sizeof(*config));
816 
817 	return 0;
818 }
819 
820 static int sun6i_dma_pause(struct dma_chan *chan)
821 {
822 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
823 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
824 	struct sun6i_pchan *pchan = vchan->phy;
825 
826 	dev_dbg(chan2dev(chan), "vchan %p: pause\n", &vchan->vc);
827 
828 	if (pchan) {
829 		writel(DMA_CHAN_PAUSE_PAUSE,
830 		       pchan->base + DMA_CHAN_PAUSE);
831 	} else {
832 		spin_lock(&sdev->lock);
833 		list_del_init(&vchan->node);
834 		spin_unlock(&sdev->lock);
835 	}
836 
837 	return 0;
838 }
839 
840 static int sun6i_dma_resume(struct dma_chan *chan)
841 {
842 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
843 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
844 	struct sun6i_pchan *pchan = vchan->phy;
845 	unsigned long flags;
846 
847 	dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc);
848 
849 	spin_lock_irqsave(&vchan->vc.lock, flags);
850 
851 	if (pchan) {
852 		writel(DMA_CHAN_PAUSE_RESUME,
853 		       pchan->base + DMA_CHAN_PAUSE);
854 	} else if (!list_empty(&vchan->vc.desc_issued)) {
855 		spin_lock(&sdev->lock);
856 		list_add_tail(&vchan->node, &sdev->pending);
857 		spin_unlock(&sdev->lock);
858 	}
859 
860 	spin_unlock_irqrestore(&vchan->vc.lock, flags);
861 
862 	return 0;
863 }
864 
865 static int sun6i_dma_terminate_all(struct dma_chan *chan)
866 {
867 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
868 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
869 	struct sun6i_pchan *pchan = vchan->phy;
870 	unsigned long flags;
871 	LIST_HEAD(head);
872 
873 	spin_lock(&sdev->lock);
874 	list_del_init(&vchan->node);
875 	spin_unlock(&sdev->lock);
876 
877 	spin_lock_irqsave(&vchan->vc.lock, flags);
878 
879 	if (vchan->cyclic) {
880 		vchan->cyclic = false;
881 		if (pchan && pchan->desc) {
882 			struct virt_dma_desc *vd = &pchan->desc->vd;
883 			struct virt_dma_chan *vc = &vchan->vc;
884 
885 			list_add_tail(&vd->node, &vc->desc_completed);
886 		}
887 	}
888 
889 	vchan_get_all_descriptors(&vchan->vc, &head);
890 
891 	if (pchan) {
892 		writel(DMA_CHAN_ENABLE_STOP, pchan->base + DMA_CHAN_ENABLE);
893 		writel(DMA_CHAN_PAUSE_RESUME, pchan->base + DMA_CHAN_PAUSE);
894 
895 		vchan->phy = NULL;
896 		pchan->vchan = NULL;
897 		pchan->desc = NULL;
898 		pchan->done = NULL;
899 	}
900 
901 	spin_unlock_irqrestore(&vchan->vc.lock, flags);
902 
903 	vchan_dma_desc_free_list(&vchan->vc, &head);
904 
905 	return 0;
906 }
907 
908 static enum dma_status sun6i_dma_tx_status(struct dma_chan *chan,
909 					   dma_cookie_t cookie,
910 					   struct dma_tx_state *state)
911 {
912 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
913 	struct sun6i_pchan *pchan = vchan->phy;
914 	struct sun6i_dma_lli *lli;
915 	struct virt_dma_desc *vd;
916 	struct sun6i_desc *txd;
917 	enum dma_status ret;
918 	unsigned long flags;
919 	size_t bytes = 0;
920 
921 	ret = dma_cookie_status(chan, cookie, state);
922 	if (ret == DMA_COMPLETE || !state)
923 		return ret;
924 
925 	spin_lock_irqsave(&vchan->vc.lock, flags);
926 
927 	vd = vchan_find_desc(&vchan->vc, cookie);
928 	txd = to_sun6i_desc(&vd->tx);
929 
930 	if (vd) {
931 		for (lli = txd->v_lli; lli != NULL; lli = lli->v_lli_next)
932 			bytes += lli->len;
933 	} else if (!pchan || !pchan->desc) {
934 		bytes = 0;
935 	} else {
936 		bytes = sun6i_get_chan_size(pchan);
937 	}
938 
939 	spin_unlock_irqrestore(&vchan->vc.lock, flags);
940 
941 	dma_set_residue(state, bytes);
942 
943 	return ret;
944 }
945 
946 static void sun6i_dma_issue_pending(struct dma_chan *chan)
947 {
948 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
949 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
950 	unsigned long flags;
951 
952 	spin_lock_irqsave(&vchan->vc.lock, flags);
953 
954 	if (vchan_issue_pending(&vchan->vc)) {
955 		spin_lock(&sdev->lock);
956 
957 		if (!vchan->phy && list_empty(&vchan->node)) {
958 			list_add_tail(&vchan->node, &sdev->pending);
959 			tasklet_schedule(&sdev->task);
960 			dev_dbg(chan2dev(chan), "vchan %p: issued\n",
961 				&vchan->vc);
962 		}
963 
964 		spin_unlock(&sdev->lock);
965 	} else {
966 		dev_dbg(chan2dev(chan), "vchan %p: nothing to issue\n",
967 			&vchan->vc);
968 	}
969 
970 	spin_unlock_irqrestore(&vchan->vc.lock, flags);
971 }
972 
973 static void sun6i_dma_free_chan_resources(struct dma_chan *chan)
974 {
975 	struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
976 	struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
977 	unsigned long flags;
978 
979 	spin_lock_irqsave(&sdev->lock, flags);
980 	list_del_init(&vchan->node);
981 	spin_unlock_irqrestore(&sdev->lock, flags);
982 
983 	vchan_free_chan_resources(&vchan->vc);
984 }
985 
986 static struct dma_chan *sun6i_dma_of_xlate(struct of_phandle_args *dma_spec,
987 					   struct of_dma *ofdma)
988 {
989 	struct sun6i_dma_dev *sdev = ofdma->of_dma_data;
990 	struct sun6i_vchan *vchan;
991 	struct dma_chan *chan;
992 	u8 port = dma_spec->args[0];
993 
994 	if (port > sdev->max_request)
995 		return NULL;
996 
997 	chan = dma_get_any_slave_channel(&sdev->slave);
998 	if (!chan)
999 		return NULL;
1000 
1001 	vchan = to_sun6i_vchan(chan);
1002 	vchan->port = port;
1003 
1004 	return chan;
1005 }
1006 
1007 static inline void sun6i_kill_tasklet(struct sun6i_dma_dev *sdev)
1008 {
1009 	/* Disable all interrupts from DMA */
1010 	writel(0, sdev->base + DMA_IRQ_EN(0));
1011 	writel(0, sdev->base + DMA_IRQ_EN(1));
1012 
1013 	/* Prevent spurious interrupts from scheduling the tasklet */
1014 	atomic_inc(&sdev->tasklet_shutdown);
1015 
1016 	/* Make sure we won't have any further interrupts */
1017 	devm_free_irq(sdev->slave.dev, sdev->irq, sdev);
1018 
1019 	/* Actually prevent the tasklet from being scheduled */
1020 	tasklet_kill(&sdev->task);
1021 }
1022 
1023 static inline void sun6i_dma_free(struct sun6i_dma_dev *sdev)
1024 {
1025 	int i;
1026 
1027 	for (i = 0; i < sdev->num_vchans; i++) {
1028 		struct sun6i_vchan *vchan = &sdev->vchans[i];
1029 
1030 		list_del(&vchan->vc.chan.device_node);
1031 		tasklet_kill(&vchan->vc.task);
1032 	}
1033 }
1034 
1035 /*
1036  * For A31:
1037  *
1038  * There's 16 physical channels that can work in parallel.
1039  *
1040  * However we have 30 different endpoints for our requests.
1041  *
1042  * Since the channels are able to handle only an unidirectional
1043  * transfer, we need to allocate more virtual channels so that
1044  * everyone can grab one channel.
1045  *
1046  * Some devices can't work in both direction (mostly because it
1047  * wouldn't make sense), so we have a bit fewer virtual channels than
1048  * 2 channels per endpoints.
1049  */
1050 
1051 static struct sun6i_dma_config sun6i_a31_dma_cfg = {
1052 	.nr_max_channels = 16,
1053 	.nr_max_requests = 30,
1054 	.nr_max_vchans   = 53,
1055 	.set_burst_length = sun6i_set_burst_length_a31,
1056 	.src_burst_lengths = BIT(1) | BIT(8),
1057 	.dst_burst_lengths = BIT(1) | BIT(8),
1058 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1059 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1060 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1061 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1062 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1063 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1064 };
1065 
1066 /*
1067  * The A23 only has 8 physical channels, a maximum DRQ port id of 24,
1068  * and a total of 37 usable source and destination endpoints.
1069  */
1070 
1071 static struct sun6i_dma_config sun8i_a23_dma_cfg = {
1072 	.nr_max_channels = 8,
1073 	.nr_max_requests = 24,
1074 	.nr_max_vchans   = 37,
1075 	.clock_autogate_enable = sun6i_enable_clock_autogate_a23,
1076 	.set_burst_length = sun6i_set_burst_length_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 static struct sun6i_dma_config sun8i_a83t_dma_cfg = {
1088 	.nr_max_channels = 8,
1089 	.nr_max_requests = 28,
1090 	.nr_max_vchans   = 39,
1091 	.clock_autogate_enable = sun6i_enable_clock_autogate_a23,
1092 	.set_burst_length = sun6i_set_burst_length_a31,
1093 	.src_burst_lengths = BIT(1) | BIT(8),
1094 	.dst_burst_lengths = BIT(1) | BIT(8),
1095 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1096 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1097 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1098 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1099 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1100 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1101 };
1102 
1103 /*
1104  * The H3 has 12 physical channels, a maximum DRQ port id of 27,
1105  * and a total of 34 usable source and destination endpoints.
1106  * It also supports additional burst lengths and bus widths,
1107  * and the burst length fields have different offsets.
1108  */
1109 
1110 static struct sun6i_dma_config sun8i_h3_dma_cfg = {
1111 	.nr_max_channels = 12,
1112 	.nr_max_requests = 27,
1113 	.nr_max_vchans   = 34,
1114 	.clock_autogate_enable = sun6i_enable_clock_autogate_h3,
1115 	.set_burst_length = sun6i_set_burst_length_h3,
1116 	.src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1117 	.dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1118 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1119 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1120 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1121 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1122 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1123 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1124 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1125 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1126 };
1127 
1128 /*
1129  * The A64 binding uses the number of dma channels from the
1130  * device tree node.
1131  */
1132 static struct sun6i_dma_config sun50i_a64_dma_cfg = {
1133 	.clock_autogate_enable = sun6i_enable_clock_autogate_h3,
1134 	.set_burst_length = sun6i_set_burst_length_h3,
1135 	.src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1136 	.dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
1137 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1138 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1139 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1140 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1141 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1142 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1143 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
1144 			     BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
1145 };
1146 
1147 /*
1148  * The V3s have only 8 physical channels, a maximum DRQ port id of 23,
1149  * and a total of 24 usable source and destination endpoints.
1150  */
1151 
1152 static struct sun6i_dma_config sun8i_v3s_dma_cfg = {
1153 	.nr_max_channels = 8,
1154 	.nr_max_requests = 23,
1155 	.nr_max_vchans   = 24,
1156 	.clock_autogate_enable = sun6i_enable_clock_autogate_a23,
1157 	.set_burst_length = sun6i_set_burst_length_a31,
1158 	.src_burst_lengths = BIT(1) | BIT(8),
1159 	.dst_burst_lengths = BIT(1) | BIT(8),
1160 	.src_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1161 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1162 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1163 	.dst_addr_widths   = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
1164 			     BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
1165 			     BIT(DMA_SLAVE_BUSWIDTH_4_BYTES),
1166 };
1167 
1168 static const struct of_device_id sun6i_dma_match[] = {
1169 	{ .compatible = "allwinner,sun6i-a31-dma", .data = &sun6i_a31_dma_cfg },
1170 	{ .compatible = "allwinner,sun8i-a23-dma", .data = &sun8i_a23_dma_cfg },
1171 	{ .compatible = "allwinner,sun8i-a83t-dma", .data = &sun8i_a83t_dma_cfg },
1172 	{ .compatible = "allwinner,sun8i-h3-dma", .data = &sun8i_h3_dma_cfg },
1173 	{ .compatible = "allwinner,sun8i-v3s-dma", .data = &sun8i_v3s_dma_cfg },
1174 	{ .compatible = "allwinner,sun50i-a64-dma", .data = &sun50i_a64_dma_cfg },
1175 	{ /* sentinel */ }
1176 };
1177 MODULE_DEVICE_TABLE(of, sun6i_dma_match);
1178 
1179 static int sun6i_dma_probe(struct platform_device *pdev)
1180 {
1181 	struct device_node *np = pdev->dev.of_node;
1182 	struct sun6i_dma_dev *sdc;
1183 	struct resource *res;
1184 	int ret, i;
1185 
1186 	sdc = devm_kzalloc(&pdev->dev, sizeof(*sdc), GFP_KERNEL);
1187 	if (!sdc)
1188 		return -ENOMEM;
1189 
1190 	sdc->cfg = of_device_get_match_data(&pdev->dev);
1191 	if (!sdc->cfg)
1192 		return -ENODEV;
1193 
1194 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1195 	sdc->base = devm_ioremap_resource(&pdev->dev, res);
1196 	if (IS_ERR(sdc->base))
1197 		return PTR_ERR(sdc->base);
1198 
1199 	sdc->irq = platform_get_irq(pdev, 0);
1200 	if (sdc->irq < 0) {
1201 		dev_err(&pdev->dev, "Cannot claim IRQ\n");
1202 		return sdc->irq;
1203 	}
1204 
1205 	sdc->clk = devm_clk_get(&pdev->dev, NULL);
1206 	if (IS_ERR(sdc->clk)) {
1207 		dev_err(&pdev->dev, "No clock specified\n");
1208 		return PTR_ERR(sdc->clk);
1209 	}
1210 
1211 	sdc->rstc = devm_reset_control_get(&pdev->dev, NULL);
1212 	if (IS_ERR(sdc->rstc)) {
1213 		dev_err(&pdev->dev, "No reset controller specified\n");
1214 		return PTR_ERR(sdc->rstc);
1215 	}
1216 
1217 	sdc->pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
1218 				     sizeof(struct sun6i_dma_lli), 4, 0);
1219 	if (!sdc->pool) {
1220 		dev_err(&pdev->dev, "No memory for descriptors dma pool\n");
1221 		return -ENOMEM;
1222 	}
1223 
1224 	platform_set_drvdata(pdev, sdc);
1225 	INIT_LIST_HEAD(&sdc->pending);
1226 	spin_lock_init(&sdc->lock);
1227 
1228 	dma_cap_set(DMA_PRIVATE, sdc->slave.cap_mask);
1229 	dma_cap_set(DMA_MEMCPY, sdc->slave.cap_mask);
1230 	dma_cap_set(DMA_SLAVE, sdc->slave.cap_mask);
1231 	dma_cap_set(DMA_CYCLIC, sdc->slave.cap_mask);
1232 
1233 	INIT_LIST_HEAD(&sdc->slave.channels);
1234 	sdc->slave.device_free_chan_resources	= sun6i_dma_free_chan_resources;
1235 	sdc->slave.device_tx_status		= sun6i_dma_tx_status;
1236 	sdc->slave.device_issue_pending		= sun6i_dma_issue_pending;
1237 	sdc->slave.device_prep_slave_sg		= sun6i_dma_prep_slave_sg;
1238 	sdc->slave.device_prep_dma_memcpy	= sun6i_dma_prep_dma_memcpy;
1239 	sdc->slave.device_prep_dma_cyclic	= sun6i_dma_prep_dma_cyclic;
1240 	sdc->slave.copy_align			= DMAENGINE_ALIGN_4_BYTES;
1241 	sdc->slave.device_config		= sun6i_dma_config;
1242 	sdc->slave.device_pause			= sun6i_dma_pause;
1243 	sdc->slave.device_resume		= sun6i_dma_resume;
1244 	sdc->slave.device_terminate_all		= sun6i_dma_terminate_all;
1245 	sdc->slave.src_addr_widths		= sdc->cfg->src_addr_widths;
1246 	sdc->slave.dst_addr_widths		= sdc->cfg->dst_addr_widths;
1247 	sdc->slave.directions			= BIT(DMA_DEV_TO_MEM) |
1248 						  BIT(DMA_MEM_TO_DEV);
1249 	sdc->slave.residue_granularity		= DMA_RESIDUE_GRANULARITY_BURST;
1250 	sdc->slave.dev = &pdev->dev;
1251 
1252 	sdc->num_pchans = sdc->cfg->nr_max_channels;
1253 	sdc->num_vchans = sdc->cfg->nr_max_vchans;
1254 	sdc->max_request = sdc->cfg->nr_max_requests;
1255 
1256 	ret = of_property_read_u32(np, "dma-channels", &sdc->num_pchans);
1257 	if (ret && !sdc->num_pchans) {
1258 		dev_err(&pdev->dev, "Can't get dma-channels.\n");
1259 		return ret;
1260 	}
1261 
1262 	ret = of_property_read_u32(np, "dma-requests", &sdc->max_request);
1263 	if (ret && !sdc->max_request) {
1264 		dev_info(&pdev->dev, "Missing dma-requests, using %u.\n",
1265 			 DMA_CHAN_MAX_DRQ);
1266 		sdc->max_request = DMA_CHAN_MAX_DRQ;
1267 	}
1268 
1269 	/*
1270 	 * If the number of vchans is not specified, derive it from the
1271 	 * highest port number, at most one channel per port and direction.
1272 	 */
1273 	if (!sdc->num_vchans)
1274 		sdc->num_vchans = 2 * (sdc->max_request + 1);
1275 
1276 	sdc->pchans = devm_kcalloc(&pdev->dev, sdc->num_pchans,
1277 				   sizeof(struct sun6i_pchan), GFP_KERNEL);
1278 	if (!sdc->pchans)
1279 		return -ENOMEM;
1280 
1281 	sdc->vchans = devm_kcalloc(&pdev->dev, sdc->num_vchans,
1282 				   sizeof(struct sun6i_vchan), GFP_KERNEL);
1283 	if (!sdc->vchans)
1284 		return -ENOMEM;
1285 
1286 	tasklet_init(&sdc->task, sun6i_dma_tasklet, (unsigned long)sdc);
1287 
1288 	for (i = 0; i < sdc->num_pchans; i++) {
1289 		struct sun6i_pchan *pchan = &sdc->pchans[i];
1290 
1291 		pchan->idx = i;
1292 		pchan->base = sdc->base + 0x100 + i * 0x40;
1293 	}
1294 
1295 	for (i = 0; i < sdc->num_vchans; i++) {
1296 		struct sun6i_vchan *vchan = &sdc->vchans[i];
1297 
1298 		INIT_LIST_HEAD(&vchan->node);
1299 		vchan->vc.desc_free = sun6i_dma_free_desc;
1300 		vchan_init(&vchan->vc, &sdc->slave);
1301 	}
1302 
1303 	ret = reset_control_deassert(sdc->rstc);
1304 	if (ret) {
1305 		dev_err(&pdev->dev, "Couldn't deassert the device from reset\n");
1306 		goto err_chan_free;
1307 	}
1308 
1309 	ret = clk_prepare_enable(sdc->clk);
1310 	if (ret) {
1311 		dev_err(&pdev->dev, "Couldn't enable the clock\n");
1312 		goto err_reset_assert;
1313 	}
1314 
1315 	ret = devm_request_irq(&pdev->dev, sdc->irq, sun6i_dma_interrupt, 0,
1316 			       dev_name(&pdev->dev), sdc);
1317 	if (ret) {
1318 		dev_err(&pdev->dev, "Cannot request IRQ\n");
1319 		goto err_clk_disable;
1320 	}
1321 
1322 	ret = dma_async_device_register(&sdc->slave);
1323 	if (ret) {
1324 		dev_warn(&pdev->dev, "Failed to register DMA engine device\n");
1325 		goto err_irq_disable;
1326 	}
1327 
1328 	ret = of_dma_controller_register(pdev->dev.of_node, sun6i_dma_of_xlate,
1329 					 sdc);
1330 	if (ret) {
1331 		dev_err(&pdev->dev, "of_dma_controller_register failed\n");
1332 		goto err_dma_unregister;
1333 	}
1334 
1335 	if (sdc->cfg->clock_autogate_enable)
1336 		sdc->cfg->clock_autogate_enable(sdc);
1337 
1338 	return 0;
1339 
1340 err_dma_unregister:
1341 	dma_async_device_unregister(&sdc->slave);
1342 err_irq_disable:
1343 	sun6i_kill_tasklet(sdc);
1344 err_clk_disable:
1345 	clk_disable_unprepare(sdc->clk);
1346 err_reset_assert:
1347 	reset_control_assert(sdc->rstc);
1348 err_chan_free:
1349 	sun6i_dma_free(sdc);
1350 	return ret;
1351 }
1352 
1353 static int sun6i_dma_remove(struct platform_device *pdev)
1354 {
1355 	struct sun6i_dma_dev *sdc = platform_get_drvdata(pdev);
1356 
1357 	of_dma_controller_free(pdev->dev.of_node);
1358 	dma_async_device_unregister(&sdc->slave);
1359 
1360 	sun6i_kill_tasklet(sdc);
1361 
1362 	clk_disable_unprepare(sdc->clk);
1363 	reset_control_assert(sdc->rstc);
1364 
1365 	sun6i_dma_free(sdc);
1366 
1367 	return 0;
1368 }
1369 
1370 static struct platform_driver sun6i_dma_driver = {
1371 	.probe		= sun6i_dma_probe,
1372 	.remove		= sun6i_dma_remove,
1373 	.driver = {
1374 		.name		= "sun6i-dma",
1375 		.of_match_table	= sun6i_dma_match,
1376 	},
1377 };
1378 module_platform_driver(sun6i_dma_driver);
1379 
1380 MODULE_DESCRIPTION("Allwinner A31 DMA Controller Driver");
1381 MODULE_AUTHOR("Sugar <shuge@allwinnertech.com>");
1382 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1383 MODULE_LICENSE("GPL");
1384