xref: /linux/drivers/dma/dma-axi-dmac.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for the Analog Devices AXI-DMAC core
4  *
5  * Copyright 2013-2019 Analog Devices Inc.
6  *  Author: Lars-Peter Clausen <lars@metafoo.de>
7  */
8 
9 #include <linux/bitfield.h>
10 #include <linux/clk.h>
11 #include <linux/device.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/dmaengine.h>
14 #include <linux/err.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/of_dma.h>
21 #include <linux/of_address.h>
22 #include <linux/platform_device.h>
23 #include <linux/regmap.h>
24 #include <linux/slab.h>
25 #include <linux/fpga/adi-axi-common.h>
26 
27 #include <dt-bindings/dma/axi-dmac.h>
28 
29 #include "dmaengine.h"
30 #include "virt-dma.h"
31 
32 /*
33  * The AXI-DMAC is a soft IP core that is used in FPGA designs. The core has
34  * various instantiation parameters which decided the exact feature set support
35  * by the core.
36  *
37  * Each channel of the core has a source interface and a destination interface.
38  * The number of channels and the type of the channel interfaces is selected at
39  * configuration time. A interface can either be a connected to a central memory
40  * interconnect, which allows access to system memory, or it can be connected to
41  * a dedicated bus which is directly connected to a data port on a peripheral.
42  * Given that those are configuration options of the core that are selected when
43  * it is instantiated this means that they can not be changed by software at
44  * runtime. By extension this means that each channel is uni-directional. It can
45  * either be device to memory or memory to device, but not both. Also since the
46  * device side is a dedicated data bus only connected to a single peripheral
47  * there is no address than can or needs to be configured for the device side.
48  */
49 
50 #define AXI_DMAC_REG_INTERFACE_DESC	0x10
51 #define   AXI_DMAC_DMA_SRC_TYPE_MSK	GENMASK(13, 12)
52 #define   AXI_DMAC_DMA_SRC_TYPE_GET(x)	FIELD_GET(AXI_DMAC_DMA_SRC_TYPE_MSK, x)
53 #define   AXI_DMAC_DMA_SRC_WIDTH_MSK	GENMASK(11, 8)
54 #define   AXI_DMAC_DMA_SRC_WIDTH_GET(x)	FIELD_GET(AXI_DMAC_DMA_SRC_WIDTH_MSK, x)
55 #define   AXI_DMAC_DMA_DST_TYPE_MSK	GENMASK(5, 4)
56 #define   AXI_DMAC_DMA_DST_TYPE_GET(x)	FIELD_GET(AXI_DMAC_DMA_DST_TYPE_MSK, x)
57 #define   AXI_DMAC_DMA_DST_WIDTH_MSK	GENMASK(3, 0)
58 #define   AXI_DMAC_DMA_DST_WIDTH_GET(x)	FIELD_GET(AXI_DMAC_DMA_DST_WIDTH_MSK, x)
59 #define AXI_DMAC_REG_COHERENCY_DESC	0x14
60 #define   AXI_DMAC_DST_COHERENT_MSK	BIT(0)
61 #define   AXI_DMAC_DST_COHERENT_GET(x)	FIELD_GET(AXI_DMAC_DST_COHERENT_MSK, x)
62 
63 #define AXI_DMAC_REG_IRQ_MASK		0x80
64 #define AXI_DMAC_REG_IRQ_PENDING	0x84
65 #define AXI_DMAC_REG_IRQ_SOURCE		0x88
66 
67 #define AXI_DMAC_REG_CTRL		0x400
68 #define AXI_DMAC_REG_TRANSFER_ID	0x404
69 #define AXI_DMAC_REG_START_TRANSFER	0x408
70 #define AXI_DMAC_REG_FLAGS		0x40c
71 #define AXI_DMAC_REG_DEST_ADDRESS	0x410
72 #define AXI_DMAC_REG_SRC_ADDRESS	0x414
73 #define AXI_DMAC_REG_X_LENGTH		0x418
74 #define AXI_DMAC_REG_Y_LENGTH		0x41c
75 #define AXI_DMAC_REG_DEST_STRIDE	0x420
76 #define AXI_DMAC_REG_SRC_STRIDE		0x424
77 #define AXI_DMAC_REG_TRANSFER_DONE	0x428
78 #define AXI_DMAC_REG_ACTIVE_TRANSFER_ID 0x42c
79 #define AXI_DMAC_REG_STATUS		0x430
80 #define AXI_DMAC_REG_CURRENT_SRC_ADDR	0x434
81 #define AXI_DMAC_REG_CURRENT_DEST_ADDR	0x438
82 #define AXI_DMAC_REG_PARTIAL_XFER_LEN	0x44c
83 #define AXI_DMAC_REG_PARTIAL_XFER_ID	0x450
84 #define AXI_DMAC_REG_CURRENT_SG_ID	0x454
85 #define AXI_DMAC_REG_SG_ADDRESS		0x47c
86 #define AXI_DMAC_REG_SG_ADDRESS_HIGH	0x4bc
87 
88 #define AXI_DMAC_CTRL_ENABLE		BIT(0)
89 #define AXI_DMAC_CTRL_PAUSE		BIT(1)
90 #define AXI_DMAC_CTRL_ENABLE_SG		BIT(2)
91 
92 #define AXI_DMAC_IRQ_SOT		BIT(0)
93 #define AXI_DMAC_IRQ_EOT		BIT(1)
94 
95 #define AXI_DMAC_FLAG_CYCLIC		BIT(0)
96 #define AXI_DMAC_FLAG_LAST		BIT(1)
97 #define AXI_DMAC_FLAG_PARTIAL_REPORT	BIT(2)
98 
99 #define AXI_DMAC_FLAG_PARTIAL_XFER_DONE BIT(31)
100 
101 /* The maximum ID allocated by the hardware is 31 */
102 #define AXI_DMAC_SG_UNUSED 32U
103 
104 /* Flags for axi_dmac_hw_desc.flags */
105 #define AXI_DMAC_HW_FLAG_LAST		BIT(0)
106 #define AXI_DMAC_HW_FLAG_IRQ		BIT(1)
107 
108 struct axi_dmac_hw_desc {
109 	u32 flags;
110 	u32 id;
111 	u64 dest_addr;
112 	u64 src_addr;
113 	u64 next_sg_addr;
114 	u32 y_len;
115 	u32 x_len;
116 	u32 src_stride;
117 	u32 dst_stride;
118 	u64 __pad[2];
119 };
120 
121 struct axi_dmac_sg {
122 	unsigned int partial_len;
123 	bool schedule_when_free;
124 
125 	struct axi_dmac_hw_desc *hw;
126 	dma_addr_t hw_phys;
127 };
128 
129 struct axi_dmac_desc {
130 	struct virt_dma_desc vdesc;
131 	struct axi_dmac_chan *chan;
132 
133 	bool cyclic;
134 	bool have_partial_xfer;
135 
136 	unsigned int num_submitted;
137 	unsigned int num_completed;
138 	unsigned int num_sgs;
139 	struct axi_dmac_sg sg[] __counted_by(num_sgs);
140 };
141 
142 struct axi_dmac_chan {
143 	struct virt_dma_chan vchan;
144 
145 	struct axi_dmac_desc *next_desc;
146 	struct list_head active_descs;
147 	enum dma_transfer_direction direction;
148 
149 	unsigned int src_width;
150 	unsigned int dest_width;
151 	unsigned int src_type;
152 	unsigned int dest_type;
153 
154 	unsigned int max_length;
155 	unsigned int address_align_mask;
156 	unsigned int length_align_mask;
157 
158 	bool hw_partial_xfer;
159 	bool hw_cyclic;
160 	bool hw_2d;
161 	bool hw_sg;
162 };
163 
164 struct axi_dmac {
165 	void __iomem *base;
166 	int irq;
167 
168 	struct clk *clk;
169 
170 	struct dma_device dma_dev;
171 	struct axi_dmac_chan chan;
172 };
173 
chan_to_axi_dmac(struct axi_dmac_chan * chan)174 static struct axi_dmac *chan_to_axi_dmac(struct axi_dmac_chan *chan)
175 {
176 	return container_of(chan->vchan.chan.device, struct axi_dmac,
177 		dma_dev);
178 }
179 
to_axi_dmac_chan(struct dma_chan * c)180 static struct axi_dmac_chan *to_axi_dmac_chan(struct dma_chan *c)
181 {
182 	return container_of(c, struct axi_dmac_chan, vchan.chan);
183 }
184 
to_axi_dmac_desc(struct virt_dma_desc * vdesc)185 static struct axi_dmac_desc *to_axi_dmac_desc(struct virt_dma_desc *vdesc)
186 {
187 	return container_of(vdesc, struct axi_dmac_desc, vdesc);
188 }
189 
axi_dmac_write(struct axi_dmac * axi_dmac,unsigned int reg,unsigned int val)190 static void axi_dmac_write(struct axi_dmac *axi_dmac, unsigned int reg,
191 	unsigned int val)
192 {
193 	writel(val, axi_dmac->base + reg);
194 }
195 
axi_dmac_read(struct axi_dmac * axi_dmac,unsigned int reg)196 static int axi_dmac_read(struct axi_dmac *axi_dmac, unsigned int reg)
197 {
198 	return readl(axi_dmac->base + reg);
199 }
200 
axi_dmac_src_is_mem(struct axi_dmac_chan * chan)201 static int axi_dmac_src_is_mem(struct axi_dmac_chan *chan)
202 {
203 	return chan->src_type == AXI_DMAC_BUS_TYPE_AXI_MM;
204 }
205 
axi_dmac_dest_is_mem(struct axi_dmac_chan * chan)206 static int axi_dmac_dest_is_mem(struct axi_dmac_chan *chan)
207 {
208 	return chan->dest_type == AXI_DMAC_BUS_TYPE_AXI_MM;
209 }
210 
axi_dmac_check_len(struct axi_dmac_chan * chan,unsigned int len)211 static bool axi_dmac_check_len(struct axi_dmac_chan *chan, unsigned int len)
212 {
213 	if (len == 0)
214 		return false;
215 	if ((len & chan->length_align_mask) != 0) /* Not aligned */
216 		return false;
217 	return true;
218 }
219 
axi_dmac_check_addr(struct axi_dmac_chan * chan,dma_addr_t addr)220 static bool axi_dmac_check_addr(struct axi_dmac_chan *chan, dma_addr_t addr)
221 {
222 	if ((addr & chan->address_align_mask) != 0) /* Not aligned */
223 		return false;
224 	return true;
225 }
226 
axi_dmac_start_transfer(struct axi_dmac_chan * chan)227 static void axi_dmac_start_transfer(struct axi_dmac_chan *chan)
228 {
229 	struct axi_dmac *dmac = chan_to_axi_dmac(chan);
230 	struct virt_dma_desc *vdesc;
231 	struct axi_dmac_desc *desc;
232 	struct axi_dmac_sg *sg;
233 	unsigned int flags = 0;
234 	unsigned int val;
235 
236 	if (!chan->hw_sg) {
237 		val = axi_dmac_read(dmac, AXI_DMAC_REG_START_TRANSFER);
238 		if (val) /* Queue is full, wait for the next SOT IRQ */
239 			return;
240 	}
241 
242 	desc = chan->next_desc;
243 
244 	if (!desc) {
245 		vdesc = vchan_next_desc(&chan->vchan);
246 		if (!vdesc)
247 			return;
248 		list_move_tail(&vdesc->node, &chan->active_descs);
249 		desc = to_axi_dmac_desc(vdesc);
250 	}
251 	sg = &desc->sg[desc->num_submitted];
252 
253 	/* Already queued in cyclic mode. Wait for it to finish */
254 	if (sg->hw->id != AXI_DMAC_SG_UNUSED) {
255 		sg->schedule_when_free = true;
256 		return;
257 	}
258 
259 	if (chan->hw_sg) {
260 		chan->next_desc = NULL;
261 	} else if (++desc->num_submitted == desc->num_sgs ||
262 		   desc->have_partial_xfer) {
263 		if (desc->cyclic)
264 			desc->num_submitted = 0; /* Start again */
265 		else
266 			chan->next_desc = NULL;
267 		flags |= AXI_DMAC_FLAG_LAST;
268 	} else {
269 		chan->next_desc = desc;
270 	}
271 
272 	sg->hw->id = axi_dmac_read(dmac, AXI_DMAC_REG_TRANSFER_ID);
273 
274 	if (!chan->hw_sg) {
275 		if (axi_dmac_dest_is_mem(chan)) {
276 			axi_dmac_write(dmac, AXI_DMAC_REG_DEST_ADDRESS, sg->hw->dest_addr);
277 			axi_dmac_write(dmac, AXI_DMAC_REG_DEST_STRIDE, sg->hw->dst_stride);
278 		}
279 
280 		if (axi_dmac_src_is_mem(chan)) {
281 			axi_dmac_write(dmac, AXI_DMAC_REG_SRC_ADDRESS, sg->hw->src_addr);
282 			axi_dmac_write(dmac, AXI_DMAC_REG_SRC_STRIDE, sg->hw->src_stride);
283 		}
284 	}
285 
286 	/*
287 	 * If the hardware supports cyclic transfers and there is no callback to
288 	 * call, enable hw cyclic mode to avoid unnecessary interrupts.
289 	 */
290 	if (chan->hw_cyclic && desc->cyclic && !desc->vdesc.tx.callback) {
291 		if (chan->hw_sg)
292 			desc->sg[desc->num_sgs - 1].hw->flags &= ~AXI_DMAC_HW_FLAG_IRQ;
293 		else if (desc->num_sgs == 1)
294 			flags |= AXI_DMAC_FLAG_CYCLIC;
295 	}
296 
297 	if (chan->hw_partial_xfer)
298 		flags |= AXI_DMAC_FLAG_PARTIAL_REPORT;
299 
300 	if (chan->hw_sg) {
301 		axi_dmac_write(dmac, AXI_DMAC_REG_SG_ADDRESS, (u32)sg->hw_phys);
302 		axi_dmac_write(dmac, AXI_DMAC_REG_SG_ADDRESS_HIGH,
303 			       (u64)sg->hw_phys >> 32);
304 	} else {
305 		axi_dmac_write(dmac, AXI_DMAC_REG_X_LENGTH, sg->hw->x_len);
306 		axi_dmac_write(dmac, AXI_DMAC_REG_Y_LENGTH, sg->hw->y_len);
307 	}
308 	axi_dmac_write(dmac, AXI_DMAC_REG_FLAGS, flags);
309 	axi_dmac_write(dmac, AXI_DMAC_REG_START_TRANSFER, 1);
310 }
311 
axi_dmac_active_desc(struct axi_dmac_chan * chan)312 static struct axi_dmac_desc *axi_dmac_active_desc(struct axi_dmac_chan *chan)
313 {
314 	return list_first_entry_or_null(&chan->active_descs,
315 		struct axi_dmac_desc, vdesc.node);
316 }
317 
axi_dmac_total_sg_bytes(struct axi_dmac_chan * chan,struct axi_dmac_sg * sg)318 static inline unsigned int axi_dmac_total_sg_bytes(struct axi_dmac_chan *chan,
319 	struct axi_dmac_sg *sg)
320 {
321 	if (chan->hw_2d)
322 		return (sg->hw->x_len + 1) * (sg->hw->y_len + 1);
323 	else
324 		return (sg->hw->x_len + 1);
325 }
326 
axi_dmac_dequeue_partial_xfers(struct axi_dmac_chan * chan)327 static void axi_dmac_dequeue_partial_xfers(struct axi_dmac_chan *chan)
328 {
329 	struct axi_dmac *dmac = chan_to_axi_dmac(chan);
330 	struct axi_dmac_desc *desc;
331 	struct axi_dmac_sg *sg;
332 	u32 xfer_done, len, id, i;
333 	bool found_sg;
334 
335 	do {
336 		len = axi_dmac_read(dmac, AXI_DMAC_REG_PARTIAL_XFER_LEN);
337 		id  = axi_dmac_read(dmac, AXI_DMAC_REG_PARTIAL_XFER_ID);
338 
339 		found_sg = false;
340 		list_for_each_entry(desc, &chan->active_descs, vdesc.node) {
341 			for (i = 0; i < desc->num_sgs; i++) {
342 				sg = &desc->sg[i];
343 				if (sg->hw->id == AXI_DMAC_SG_UNUSED)
344 					continue;
345 				if (sg->hw->id == id) {
346 					desc->have_partial_xfer = true;
347 					sg->partial_len = len;
348 					found_sg = true;
349 					break;
350 				}
351 			}
352 			if (found_sg)
353 				break;
354 		}
355 
356 		if (found_sg) {
357 			dev_dbg(dmac->dma_dev.dev,
358 				"Found partial segment id=%u, len=%u\n",
359 				id, len);
360 		} else {
361 			dev_warn(dmac->dma_dev.dev,
362 				 "Not found partial segment id=%u, len=%u\n",
363 				 id, len);
364 		}
365 
366 		/* Check if we have any more partial transfers */
367 		xfer_done = axi_dmac_read(dmac, AXI_DMAC_REG_TRANSFER_DONE);
368 		xfer_done = !(xfer_done & AXI_DMAC_FLAG_PARTIAL_XFER_DONE);
369 
370 	} while (!xfer_done);
371 }
372 
axi_dmac_compute_residue(struct axi_dmac_chan * chan,struct axi_dmac_desc * active)373 static void axi_dmac_compute_residue(struct axi_dmac_chan *chan,
374 	struct axi_dmac_desc *active)
375 {
376 	struct dmaengine_result *rslt = &active->vdesc.tx_result;
377 	unsigned int start = active->num_completed - 1;
378 	struct axi_dmac_sg *sg;
379 	unsigned int i, total;
380 
381 	rslt->result = DMA_TRANS_NOERROR;
382 	rslt->residue = 0;
383 
384 	if (chan->hw_sg)
385 		return;
386 
387 	/*
388 	 * We get here if the last completed segment is partial, which
389 	 * means we can compute the residue from that segment onwards
390 	 */
391 	for (i = start; i < active->num_sgs; i++) {
392 		sg = &active->sg[i];
393 		total = axi_dmac_total_sg_bytes(chan, sg);
394 		rslt->residue += (total - sg->partial_len);
395 	}
396 }
397 
axi_dmac_transfer_done(struct axi_dmac_chan * chan,unsigned int completed_transfers)398 static bool axi_dmac_transfer_done(struct axi_dmac_chan *chan,
399 	unsigned int completed_transfers)
400 {
401 	struct axi_dmac_desc *active;
402 	struct axi_dmac_sg *sg;
403 	bool start_next = false;
404 
405 	active = axi_dmac_active_desc(chan);
406 	if (!active)
407 		return false;
408 
409 	if (chan->hw_partial_xfer &&
410 	    (completed_transfers & AXI_DMAC_FLAG_PARTIAL_XFER_DONE))
411 		axi_dmac_dequeue_partial_xfers(chan);
412 
413 	if (chan->hw_sg) {
414 		if (active->cyclic) {
415 			vchan_cyclic_callback(&active->vdesc);
416 		} else {
417 			list_del(&active->vdesc.node);
418 			vchan_cookie_complete(&active->vdesc);
419 			active = axi_dmac_active_desc(chan);
420 			start_next = !!active;
421 		}
422 	} else {
423 		do {
424 			sg = &active->sg[active->num_completed];
425 			if (sg->hw->id == AXI_DMAC_SG_UNUSED) /* Not yet submitted */
426 				break;
427 			if (!(BIT(sg->hw->id) & completed_transfers))
428 				break;
429 			active->num_completed++;
430 			sg->hw->id = AXI_DMAC_SG_UNUSED;
431 			if (sg->schedule_when_free) {
432 				sg->schedule_when_free = false;
433 				start_next = true;
434 			}
435 
436 			if (sg->partial_len)
437 				axi_dmac_compute_residue(chan, active);
438 
439 			if (active->cyclic)
440 				vchan_cyclic_callback(&active->vdesc);
441 
442 			if (active->num_completed == active->num_sgs ||
443 			    sg->partial_len) {
444 				if (active->cyclic) {
445 					active->num_completed = 0; /* wrap around */
446 				} else {
447 					list_del(&active->vdesc.node);
448 					vchan_cookie_complete(&active->vdesc);
449 					active = axi_dmac_active_desc(chan);
450 				}
451 			}
452 		} while (active);
453 	}
454 
455 	return start_next;
456 }
457 
axi_dmac_interrupt_handler(int irq,void * devid)458 static irqreturn_t axi_dmac_interrupt_handler(int irq, void *devid)
459 {
460 	struct axi_dmac *dmac = devid;
461 	unsigned int pending;
462 	bool start_next = false;
463 
464 	pending = axi_dmac_read(dmac, AXI_DMAC_REG_IRQ_PENDING);
465 	if (!pending)
466 		return IRQ_NONE;
467 
468 	axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_PENDING, pending);
469 
470 	spin_lock(&dmac->chan.vchan.lock);
471 	/* One or more transfers have finished */
472 	if (pending & AXI_DMAC_IRQ_EOT) {
473 		unsigned int completed;
474 
475 		completed = axi_dmac_read(dmac, AXI_DMAC_REG_TRANSFER_DONE);
476 		start_next = axi_dmac_transfer_done(&dmac->chan, completed);
477 	}
478 	/* Space has become available in the descriptor queue */
479 	if ((pending & AXI_DMAC_IRQ_SOT) || start_next)
480 		axi_dmac_start_transfer(&dmac->chan);
481 	spin_unlock(&dmac->chan.vchan.lock);
482 
483 	return IRQ_HANDLED;
484 }
485 
axi_dmac_terminate_all(struct dma_chan * c)486 static int axi_dmac_terminate_all(struct dma_chan *c)
487 {
488 	struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
489 	struct axi_dmac *dmac = chan_to_axi_dmac(chan);
490 	unsigned long flags;
491 	LIST_HEAD(head);
492 
493 	spin_lock_irqsave(&chan->vchan.lock, flags);
494 	axi_dmac_write(dmac, AXI_DMAC_REG_CTRL, 0);
495 	chan->next_desc = NULL;
496 	vchan_get_all_descriptors(&chan->vchan, &head);
497 	list_splice_tail_init(&chan->active_descs, &head);
498 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
499 
500 	vchan_dma_desc_free_list(&chan->vchan, &head);
501 
502 	return 0;
503 }
504 
axi_dmac_synchronize(struct dma_chan * c)505 static void axi_dmac_synchronize(struct dma_chan *c)
506 {
507 	struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
508 
509 	vchan_synchronize(&chan->vchan);
510 }
511 
axi_dmac_issue_pending(struct dma_chan * c)512 static void axi_dmac_issue_pending(struct dma_chan *c)
513 {
514 	struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
515 	struct axi_dmac *dmac = chan_to_axi_dmac(chan);
516 	unsigned long flags;
517 	u32 ctrl = AXI_DMAC_CTRL_ENABLE;
518 
519 	if (chan->hw_sg)
520 		ctrl |= AXI_DMAC_CTRL_ENABLE_SG;
521 
522 	axi_dmac_write(dmac, AXI_DMAC_REG_CTRL, ctrl);
523 
524 	spin_lock_irqsave(&chan->vchan.lock, flags);
525 	if (vchan_issue_pending(&chan->vchan))
526 		axi_dmac_start_transfer(chan);
527 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
528 }
529 
530 static struct axi_dmac_desc *
axi_dmac_alloc_desc(struct axi_dmac_chan * chan,unsigned int num_sgs)531 axi_dmac_alloc_desc(struct axi_dmac_chan *chan, unsigned int num_sgs)
532 {
533 	struct axi_dmac *dmac = chan_to_axi_dmac(chan);
534 	struct device *dev = dmac->dma_dev.dev;
535 	struct axi_dmac_hw_desc *hws;
536 	struct axi_dmac_desc *desc;
537 	dma_addr_t hw_phys;
538 	unsigned int i;
539 
540 	desc = kzalloc(struct_size(desc, sg, num_sgs), GFP_NOWAIT);
541 	if (!desc)
542 		return NULL;
543 	desc->num_sgs = num_sgs;
544 	desc->chan = chan;
545 
546 	hws = dma_alloc_coherent(dev, PAGE_ALIGN(num_sgs * sizeof(*hws)),
547 				&hw_phys, GFP_ATOMIC);
548 	if (!hws) {
549 		kfree(desc);
550 		return NULL;
551 	}
552 
553 	for (i = 0; i < num_sgs; i++) {
554 		desc->sg[i].hw = &hws[i];
555 		desc->sg[i].hw_phys = hw_phys + i * sizeof(*hws);
556 
557 		hws[i].id = AXI_DMAC_SG_UNUSED;
558 		hws[i].flags = 0;
559 
560 		/* Link hardware descriptors */
561 		hws[i].next_sg_addr = hw_phys + (i + 1) * sizeof(*hws);
562 	}
563 
564 	/* The last hardware descriptor will trigger an interrupt */
565 	desc->sg[num_sgs - 1].hw->flags = AXI_DMAC_HW_FLAG_LAST | AXI_DMAC_HW_FLAG_IRQ;
566 
567 	return desc;
568 }
569 
axi_dmac_free_desc(struct axi_dmac_desc * desc)570 static void axi_dmac_free_desc(struct axi_dmac_desc *desc)
571 {
572 	struct axi_dmac *dmac = chan_to_axi_dmac(desc->chan);
573 	struct device *dev = dmac->dma_dev.dev;
574 	struct axi_dmac_hw_desc *hw = desc->sg[0].hw;
575 	dma_addr_t hw_phys = desc->sg[0].hw_phys;
576 
577 	dma_free_coherent(dev, PAGE_ALIGN(desc->num_sgs * sizeof(*hw)),
578 			  hw, hw_phys);
579 	kfree(desc);
580 }
581 
axi_dmac_fill_linear_sg(struct axi_dmac_chan * chan,enum dma_transfer_direction direction,dma_addr_t addr,unsigned int num_periods,unsigned int period_len,struct axi_dmac_sg * sg)582 static struct axi_dmac_sg *axi_dmac_fill_linear_sg(struct axi_dmac_chan *chan,
583 	enum dma_transfer_direction direction, dma_addr_t addr,
584 	unsigned int num_periods, unsigned int period_len,
585 	struct axi_dmac_sg *sg)
586 {
587 	unsigned int num_segments, i;
588 	unsigned int segment_size;
589 	unsigned int len;
590 
591 	/* Split into multiple equally sized segments if necessary */
592 	num_segments = DIV_ROUND_UP(period_len, chan->max_length);
593 	segment_size = DIV_ROUND_UP(period_len, num_segments);
594 	/* Take care of alignment */
595 	segment_size = ((segment_size - 1) | chan->length_align_mask) + 1;
596 
597 	for (i = 0; i < num_periods; i++) {
598 		for (len = period_len; len > segment_size; sg++) {
599 			if (direction == DMA_DEV_TO_MEM)
600 				sg->hw->dest_addr = addr;
601 			else
602 				sg->hw->src_addr = addr;
603 			sg->hw->x_len = segment_size - 1;
604 			sg->hw->y_len = 0;
605 			sg->hw->flags = 0;
606 			addr += segment_size;
607 			len -= segment_size;
608 		}
609 
610 		if (direction == DMA_DEV_TO_MEM)
611 			sg->hw->dest_addr = addr;
612 		else
613 			sg->hw->src_addr = addr;
614 		sg->hw->x_len = len - 1;
615 		sg->hw->y_len = 0;
616 		sg++;
617 		addr += len;
618 	}
619 
620 	return sg;
621 }
622 
623 static struct dma_async_tx_descriptor *
axi_dmac_prep_peripheral_dma_vec(struct dma_chan * c,const struct dma_vec * vecs,size_t nb,enum dma_transfer_direction direction,unsigned long flags)624 axi_dmac_prep_peripheral_dma_vec(struct dma_chan *c, const struct dma_vec *vecs,
625 				 size_t nb, enum dma_transfer_direction direction,
626 				 unsigned long flags)
627 {
628 	struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
629 	struct axi_dmac_desc *desc;
630 	unsigned int num_sgs = 0;
631 	struct axi_dmac_sg *dsg;
632 	size_t i;
633 
634 	if (direction != chan->direction)
635 		return NULL;
636 
637 	for (i = 0; i < nb; i++)
638 		num_sgs += DIV_ROUND_UP(vecs[i].len, chan->max_length);
639 
640 	desc = axi_dmac_alloc_desc(chan, num_sgs);
641 	if (!desc)
642 		return NULL;
643 
644 	dsg = desc->sg;
645 
646 	for (i = 0; i < nb; i++) {
647 		if (!axi_dmac_check_addr(chan, vecs[i].addr) ||
648 		    !axi_dmac_check_len(chan, vecs[i].len)) {
649 			kfree(desc);
650 			return NULL;
651 		}
652 
653 		dsg = axi_dmac_fill_linear_sg(chan, direction, vecs[i].addr, 1,
654 					      vecs[i].len, dsg);
655 	}
656 
657 	desc->cyclic = false;
658 
659 	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
660 }
661 
axi_dmac_prep_slave_sg(struct dma_chan * c,struct scatterlist * sgl,unsigned int sg_len,enum dma_transfer_direction direction,unsigned long flags,void * context)662 static struct dma_async_tx_descriptor *axi_dmac_prep_slave_sg(
663 	struct dma_chan *c, struct scatterlist *sgl,
664 	unsigned int sg_len, enum dma_transfer_direction direction,
665 	unsigned long flags, void *context)
666 {
667 	struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
668 	struct axi_dmac_desc *desc;
669 	struct axi_dmac_sg *dsg;
670 	struct scatterlist *sg;
671 	unsigned int num_sgs;
672 	unsigned int i;
673 
674 	if (direction != chan->direction)
675 		return NULL;
676 
677 	num_sgs = 0;
678 	for_each_sg(sgl, sg, sg_len, i)
679 		num_sgs += DIV_ROUND_UP(sg_dma_len(sg), chan->max_length);
680 
681 	desc = axi_dmac_alloc_desc(chan, num_sgs);
682 	if (!desc)
683 		return NULL;
684 
685 	dsg = desc->sg;
686 
687 	for_each_sg(sgl, sg, sg_len, i) {
688 		if (!axi_dmac_check_addr(chan, sg_dma_address(sg)) ||
689 		    !axi_dmac_check_len(chan, sg_dma_len(sg))) {
690 			axi_dmac_free_desc(desc);
691 			return NULL;
692 		}
693 
694 		dsg = axi_dmac_fill_linear_sg(chan, direction, sg_dma_address(sg), 1,
695 			sg_dma_len(sg), dsg);
696 	}
697 
698 	desc->cyclic = false;
699 
700 	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
701 }
702 
axi_dmac_prep_dma_cyclic(struct dma_chan * c,dma_addr_t buf_addr,size_t buf_len,size_t period_len,enum dma_transfer_direction direction,unsigned long flags)703 static struct dma_async_tx_descriptor *axi_dmac_prep_dma_cyclic(
704 	struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len,
705 	size_t period_len, enum dma_transfer_direction direction,
706 	unsigned long flags)
707 {
708 	struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
709 	struct axi_dmac_desc *desc;
710 	unsigned int num_periods, num_segments, num_sgs;
711 
712 	if (direction != chan->direction)
713 		return NULL;
714 
715 	if (!axi_dmac_check_len(chan, buf_len) ||
716 	    !axi_dmac_check_addr(chan, buf_addr))
717 		return NULL;
718 
719 	if (period_len == 0 || buf_len % period_len)
720 		return NULL;
721 
722 	num_periods = buf_len / period_len;
723 	num_segments = DIV_ROUND_UP(period_len, chan->max_length);
724 	num_sgs = num_periods * num_segments;
725 
726 	desc = axi_dmac_alloc_desc(chan, num_sgs);
727 	if (!desc)
728 		return NULL;
729 
730 	/* Chain the last descriptor to the first, and remove its "last" flag */
731 	desc->sg[num_sgs - 1].hw->next_sg_addr = desc->sg[0].hw_phys;
732 	desc->sg[num_sgs - 1].hw->flags &= ~AXI_DMAC_HW_FLAG_LAST;
733 
734 	axi_dmac_fill_linear_sg(chan, direction, buf_addr, num_periods,
735 		period_len, desc->sg);
736 
737 	desc->cyclic = true;
738 
739 	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
740 }
741 
axi_dmac_prep_interleaved(struct dma_chan * c,struct dma_interleaved_template * xt,unsigned long flags)742 static struct dma_async_tx_descriptor *axi_dmac_prep_interleaved(
743 	struct dma_chan *c, struct dma_interleaved_template *xt,
744 	unsigned long flags)
745 {
746 	struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
747 	struct axi_dmac_desc *desc;
748 	size_t dst_icg, src_icg;
749 
750 	if (xt->frame_size != 1)
751 		return NULL;
752 
753 	if (xt->dir != chan->direction)
754 		return NULL;
755 
756 	if (axi_dmac_src_is_mem(chan)) {
757 		if (!xt->src_inc || !axi_dmac_check_addr(chan, xt->src_start))
758 			return NULL;
759 	}
760 
761 	if (axi_dmac_dest_is_mem(chan)) {
762 		if (!xt->dst_inc || !axi_dmac_check_addr(chan, xt->dst_start))
763 			return NULL;
764 	}
765 
766 	dst_icg = dmaengine_get_dst_icg(xt, &xt->sgl[0]);
767 	src_icg = dmaengine_get_src_icg(xt, &xt->sgl[0]);
768 
769 	if (chan->hw_2d) {
770 		if (!axi_dmac_check_len(chan, xt->sgl[0].size) ||
771 		    xt->numf == 0)
772 			return NULL;
773 		if (xt->sgl[0].size + dst_icg > chan->max_length ||
774 		    xt->sgl[0].size + src_icg > chan->max_length)
775 			return NULL;
776 	} else {
777 		if (dst_icg != 0 || src_icg != 0)
778 			return NULL;
779 		if (chan->max_length / xt->sgl[0].size < xt->numf)
780 			return NULL;
781 		if (!axi_dmac_check_len(chan, xt->sgl[0].size * xt->numf))
782 			return NULL;
783 	}
784 
785 	desc = axi_dmac_alloc_desc(chan, 1);
786 	if (!desc)
787 		return NULL;
788 
789 	if (axi_dmac_src_is_mem(chan)) {
790 		desc->sg[0].hw->src_addr = xt->src_start;
791 		desc->sg[0].hw->src_stride = xt->sgl[0].size + src_icg;
792 	}
793 
794 	if (axi_dmac_dest_is_mem(chan)) {
795 		desc->sg[0].hw->dest_addr = xt->dst_start;
796 		desc->sg[0].hw->dst_stride = xt->sgl[0].size + dst_icg;
797 	}
798 
799 	if (chan->hw_2d) {
800 		desc->sg[0].hw->x_len = xt->sgl[0].size - 1;
801 		desc->sg[0].hw->y_len = xt->numf - 1;
802 	} else {
803 		desc->sg[0].hw->x_len = xt->sgl[0].size * xt->numf - 1;
804 		desc->sg[0].hw->y_len = 0;
805 	}
806 
807 	if (flags & DMA_CYCLIC)
808 		desc->cyclic = true;
809 
810 	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
811 }
812 
axi_dmac_free_chan_resources(struct dma_chan * c)813 static void axi_dmac_free_chan_resources(struct dma_chan *c)
814 {
815 	vchan_free_chan_resources(to_virt_chan(c));
816 }
817 
axi_dmac_desc_free(struct virt_dma_desc * vdesc)818 static void axi_dmac_desc_free(struct virt_dma_desc *vdesc)
819 {
820 	axi_dmac_free_desc(to_axi_dmac_desc(vdesc));
821 }
822 
axi_dmac_regmap_rdwr(struct device * dev,unsigned int reg)823 static bool axi_dmac_regmap_rdwr(struct device *dev, unsigned int reg)
824 {
825 	switch (reg) {
826 	case AXI_DMAC_REG_IRQ_MASK:
827 	case AXI_DMAC_REG_IRQ_SOURCE:
828 	case AXI_DMAC_REG_IRQ_PENDING:
829 	case AXI_DMAC_REG_CTRL:
830 	case AXI_DMAC_REG_TRANSFER_ID:
831 	case AXI_DMAC_REG_START_TRANSFER:
832 	case AXI_DMAC_REG_FLAGS:
833 	case AXI_DMAC_REG_DEST_ADDRESS:
834 	case AXI_DMAC_REG_SRC_ADDRESS:
835 	case AXI_DMAC_REG_X_LENGTH:
836 	case AXI_DMAC_REG_Y_LENGTH:
837 	case AXI_DMAC_REG_DEST_STRIDE:
838 	case AXI_DMAC_REG_SRC_STRIDE:
839 	case AXI_DMAC_REG_TRANSFER_DONE:
840 	case AXI_DMAC_REG_ACTIVE_TRANSFER_ID:
841 	case AXI_DMAC_REG_STATUS:
842 	case AXI_DMAC_REG_CURRENT_SRC_ADDR:
843 	case AXI_DMAC_REG_CURRENT_DEST_ADDR:
844 	case AXI_DMAC_REG_PARTIAL_XFER_LEN:
845 	case AXI_DMAC_REG_PARTIAL_XFER_ID:
846 	case AXI_DMAC_REG_CURRENT_SG_ID:
847 	case AXI_DMAC_REG_SG_ADDRESS:
848 	case AXI_DMAC_REG_SG_ADDRESS_HIGH:
849 		return true;
850 	default:
851 		return false;
852 	}
853 }
854 
855 static const struct regmap_config axi_dmac_regmap_config = {
856 	.reg_bits = 32,
857 	.val_bits = 32,
858 	.reg_stride = 4,
859 	.max_register = AXI_DMAC_REG_PARTIAL_XFER_ID,
860 	.readable_reg = axi_dmac_regmap_rdwr,
861 	.writeable_reg = axi_dmac_regmap_rdwr,
862 };
863 
axi_dmac_adjust_chan_params(struct axi_dmac_chan * chan)864 static void axi_dmac_adjust_chan_params(struct axi_dmac_chan *chan)
865 {
866 	chan->address_align_mask = max(chan->dest_width, chan->src_width) - 1;
867 
868 	if (axi_dmac_dest_is_mem(chan) && axi_dmac_src_is_mem(chan))
869 		chan->direction = DMA_MEM_TO_MEM;
870 	else if (!axi_dmac_dest_is_mem(chan) && axi_dmac_src_is_mem(chan))
871 		chan->direction = DMA_MEM_TO_DEV;
872 	else if (axi_dmac_dest_is_mem(chan) && !axi_dmac_src_is_mem(chan))
873 		chan->direction = DMA_DEV_TO_MEM;
874 	else
875 		chan->direction = DMA_DEV_TO_DEV;
876 }
877 
878 /*
879  * The configuration stored in the devicetree matches the configuration
880  * parameters of the peripheral instance and allows the driver to know which
881  * features are implemented and how it should behave.
882  */
axi_dmac_parse_chan_dt(struct device_node * of_chan,struct axi_dmac_chan * chan)883 static int axi_dmac_parse_chan_dt(struct device_node *of_chan,
884 	struct axi_dmac_chan *chan)
885 {
886 	u32 val;
887 	int ret;
888 
889 	ret = of_property_read_u32(of_chan, "reg", &val);
890 	if (ret)
891 		return ret;
892 
893 	/* We only support 1 channel for now */
894 	if (val != 0)
895 		return -EINVAL;
896 
897 	ret = of_property_read_u32(of_chan, "adi,source-bus-type", &val);
898 	if (ret)
899 		return ret;
900 	if (val > AXI_DMAC_BUS_TYPE_FIFO)
901 		return -EINVAL;
902 	chan->src_type = val;
903 
904 	ret = of_property_read_u32(of_chan, "adi,destination-bus-type", &val);
905 	if (ret)
906 		return ret;
907 	if (val > AXI_DMAC_BUS_TYPE_FIFO)
908 		return -EINVAL;
909 	chan->dest_type = val;
910 
911 	ret = of_property_read_u32(of_chan, "adi,source-bus-width", &val);
912 	if (ret)
913 		return ret;
914 	chan->src_width = val / 8;
915 
916 	ret = of_property_read_u32(of_chan, "adi,destination-bus-width", &val);
917 	if (ret)
918 		return ret;
919 	chan->dest_width = val / 8;
920 
921 	axi_dmac_adjust_chan_params(chan);
922 
923 	return 0;
924 }
925 
axi_dmac_parse_dt(struct device * dev,struct axi_dmac * dmac)926 static int axi_dmac_parse_dt(struct device *dev, struct axi_dmac *dmac)
927 {
928 	struct device_node *of_channels, *of_chan;
929 	int ret;
930 
931 	of_channels = of_get_child_by_name(dev->of_node, "adi,channels");
932 	if (of_channels == NULL)
933 		return -ENODEV;
934 
935 	for_each_child_of_node(of_channels, of_chan) {
936 		ret = axi_dmac_parse_chan_dt(of_chan, &dmac->chan);
937 		if (ret) {
938 			of_node_put(of_chan);
939 			of_node_put(of_channels);
940 			return -EINVAL;
941 		}
942 	}
943 	of_node_put(of_channels);
944 
945 	return 0;
946 }
947 
axi_dmac_read_chan_config(struct device * dev,struct axi_dmac * dmac)948 static int axi_dmac_read_chan_config(struct device *dev, struct axi_dmac *dmac)
949 {
950 	struct axi_dmac_chan *chan = &dmac->chan;
951 	unsigned int val, desc;
952 
953 	desc = axi_dmac_read(dmac, AXI_DMAC_REG_INTERFACE_DESC);
954 	if (desc == 0) {
955 		dev_err(dev, "DMA interface register reads zero\n");
956 		return -EFAULT;
957 	}
958 
959 	val = AXI_DMAC_DMA_SRC_TYPE_GET(desc);
960 	if (val > AXI_DMAC_BUS_TYPE_FIFO) {
961 		dev_err(dev, "Invalid source bus type read: %d\n", val);
962 		return -EINVAL;
963 	}
964 	chan->src_type = val;
965 
966 	val = AXI_DMAC_DMA_DST_TYPE_GET(desc);
967 	if (val > AXI_DMAC_BUS_TYPE_FIFO) {
968 		dev_err(dev, "Invalid destination bus type read: %d\n", val);
969 		return -EINVAL;
970 	}
971 	chan->dest_type = val;
972 
973 	val = AXI_DMAC_DMA_SRC_WIDTH_GET(desc);
974 	if (val == 0) {
975 		dev_err(dev, "Source bus width is zero\n");
976 		return -EINVAL;
977 	}
978 	/* widths are stored in log2 */
979 	chan->src_width = 1 << val;
980 
981 	val = AXI_DMAC_DMA_DST_WIDTH_GET(desc);
982 	if (val == 0) {
983 		dev_err(dev, "Destination bus width is zero\n");
984 		return -EINVAL;
985 	}
986 	chan->dest_width = 1 << val;
987 
988 	axi_dmac_adjust_chan_params(chan);
989 
990 	return 0;
991 }
992 
axi_dmac_detect_caps(struct axi_dmac * dmac,unsigned int version)993 static int axi_dmac_detect_caps(struct axi_dmac *dmac, unsigned int version)
994 {
995 	struct axi_dmac_chan *chan = &dmac->chan;
996 
997 	axi_dmac_write(dmac, AXI_DMAC_REG_FLAGS, AXI_DMAC_FLAG_CYCLIC);
998 	if (axi_dmac_read(dmac, AXI_DMAC_REG_FLAGS) == AXI_DMAC_FLAG_CYCLIC)
999 		chan->hw_cyclic = true;
1000 
1001 	axi_dmac_write(dmac, AXI_DMAC_REG_SG_ADDRESS, 0xffffffff);
1002 	if (axi_dmac_read(dmac, AXI_DMAC_REG_SG_ADDRESS))
1003 		chan->hw_sg = true;
1004 
1005 	axi_dmac_write(dmac, AXI_DMAC_REG_Y_LENGTH, 1);
1006 	if (axi_dmac_read(dmac, AXI_DMAC_REG_Y_LENGTH) == 1)
1007 		chan->hw_2d = true;
1008 
1009 	axi_dmac_write(dmac, AXI_DMAC_REG_X_LENGTH, 0xffffffff);
1010 	chan->max_length = axi_dmac_read(dmac, AXI_DMAC_REG_X_LENGTH);
1011 	if (chan->max_length != UINT_MAX)
1012 		chan->max_length++;
1013 
1014 	axi_dmac_write(dmac, AXI_DMAC_REG_DEST_ADDRESS, 0xffffffff);
1015 	if (axi_dmac_read(dmac, AXI_DMAC_REG_DEST_ADDRESS) == 0 &&
1016 	    chan->dest_type == AXI_DMAC_BUS_TYPE_AXI_MM) {
1017 		dev_err(dmac->dma_dev.dev,
1018 			"Destination memory-mapped interface not supported.");
1019 		return -ENODEV;
1020 	}
1021 
1022 	axi_dmac_write(dmac, AXI_DMAC_REG_SRC_ADDRESS, 0xffffffff);
1023 	if (axi_dmac_read(dmac, AXI_DMAC_REG_SRC_ADDRESS) == 0 &&
1024 	    chan->src_type == AXI_DMAC_BUS_TYPE_AXI_MM) {
1025 		dev_err(dmac->dma_dev.dev,
1026 			"Source memory-mapped interface not supported.");
1027 		return -ENODEV;
1028 	}
1029 
1030 	if (version >= ADI_AXI_PCORE_VER(4, 2, 'a'))
1031 		chan->hw_partial_xfer = true;
1032 
1033 	if (version >= ADI_AXI_PCORE_VER(4, 1, 'a')) {
1034 		axi_dmac_write(dmac, AXI_DMAC_REG_X_LENGTH, 0x00);
1035 		chan->length_align_mask =
1036 			axi_dmac_read(dmac, AXI_DMAC_REG_X_LENGTH);
1037 	} else {
1038 		chan->length_align_mask = chan->address_align_mask;
1039 	}
1040 
1041 	return 0;
1042 }
1043 
axi_dmac_tasklet_kill(void * task)1044 static void axi_dmac_tasklet_kill(void *task)
1045 {
1046 	tasklet_kill(task);
1047 }
1048 
axi_dmac_free_dma_controller(void * of_node)1049 static void axi_dmac_free_dma_controller(void *of_node)
1050 {
1051 	of_dma_controller_free(of_node);
1052 }
1053 
axi_dmac_probe(struct platform_device * pdev)1054 static int axi_dmac_probe(struct platform_device *pdev)
1055 {
1056 	struct dma_device *dma_dev;
1057 	struct axi_dmac *dmac;
1058 	struct regmap *regmap;
1059 	unsigned int version;
1060 	u32 irq_mask = 0;
1061 	int ret;
1062 
1063 	dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL);
1064 	if (!dmac)
1065 		return -ENOMEM;
1066 
1067 	dmac->irq = platform_get_irq(pdev, 0);
1068 	if (dmac->irq < 0)
1069 		return dmac->irq;
1070 	if (dmac->irq == 0)
1071 		return -EINVAL;
1072 
1073 	dmac->base = devm_platform_ioremap_resource(pdev, 0);
1074 	if (IS_ERR(dmac->base))
1075 		return PTR_ERR(dmac->base);
1076 
1077 	dmac->clk = devm_clk_get_enabled(&pdev->dev, NULL);
1078 	if (IS_ERR(dmac->clk))
1079 		return PTR_ERR(dmac->clk);
1080 
1081 	version = axi_dmac_read(dmac, ADI_AXI_REG_VERSION);
1082 
1083 	if (version >= ADI_AXI_PCORE_VER(4, 3, 'a'))
1084 		ret = axi_dmac_read_chan_config(&pdev->dev, dmac);
1085 	else
1086 		ret = axi_dmac_parse_dt(&pdev->dev, dmac);
1087 
1088 	if (ret < 0)
1089 		return ret;
1090 
1091 	INIT_LIST_HEAD(&dmac->chan.active_descs);
1092 
1093 	dma_set_max_seg_size(&pdev->dev, UINT_MAX);
1094 
1095 	dma_dev = &dmac->dma_dev;
1096 	dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
1097 	dma_cap_set(DMA_CYCLIC, dma_dev->cap_mask);
1098 	dma_cap_set(DMA_INTERLEAVE, dma_dev->cap_mask);
1099 	dma_dev->device_free_chan_resources = axi_dmac_free_chan_resources;
1100 	dma_dev->device_tx_status = dma_cookie_status;
1101 	dma_dev->device_issue_pending = axi_dmac_issue_pending;
1102 	dma_dev->device_prep_slave_sg = axi_dmac_prep_slave_sg;
1103 	dma_dev->device_prep_peripheral_dma_vec = axi_dmac_prep_peripheral_dma_vec;
1104 	dma_dev->device_prep_dma_cyclic = axi_dmac_prep_dma_cyclic;
1105 	dma_dev->device_prep_interleaved_dma = axi_dmac_prep_interleaved;
1106 	dma_dev->device_terminate_all = axi_dmac_terminate_all;
1107 	dma_dev->device_synchronize = axi_dmac_synchronize;
1108 	dma_dev->dev = &pdev->dev;
1109 	dma_dev->src_addr_widths = BIT(dmac->chan.src_width);
1110 	dma_dev->dst_addr_widths = BIT(dmac->chan.dest_width);
1111 	dma_dev->directions = BIT(dmac->chan.direction);
1112 	dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1113 	dma_dev->max_sg_burst = 31; /* 31 SGs maximum in one burst */
1114 	INIT_LIST_HEAD(&dma_dev->channels);
1115 
1116 	dmac->chan.vchan.desc_free = axi_dmac_desc_free;
1117 	vchan_init(&dmac->chan.vchan, dma_dev);
1118 
1119 	ret = axi_dmac_detect_caps(dmac, version);
1120 	if (ret)
1121 		return ret;
1122 
1123 	dma_dev->copy_align = (dmac->chan.address_align_mask + 1);
1124 
1125 	if (dmac->chan.hw_sg)
1126 		irq_mask |= AXI_DMAC_IRQ_SOT;
1127 
1128 	axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, irq_mask);
1129 
1130 	if (of_dma_is_coherent(pdev->dev.of_node)) {
1131 		ret = axi_dmac_read(dmac, AXI_DMAC_REG_COHERENCY_DESC);
1132 
1133 		if (version < ADI_AXI_PCORE_VER(4, 4, 'a') ||
1134 		    !AXI_DMAC_DST_COHERENT_GET(ret)) {
1135 			dev_err(dmac->dma_dev.dev,
1136 				"Coherent DMA not supported in hardware");
1137 			return -EINVAL;
1138 		}
1139 	}
1140 
1141 	ret = dmaenginem_async_device_register(dma_dev);
1142 	if (ret)
1143 		return ret;
1144 
1145 	/*
1146 	 * Put the action in here so it get's done before unregistering the DMA
1147 	 * device.
1148 	 */
1149 	ret = devm_add_action_or_reset(&pdev->dev, axi_dmac_tasklet_kill,
1150 				       &dmac->chan.vchan.task);
1151 	if (ret)
1152 		return ret;
1153 
1154 	ret = of_dma_controller_register(pdev->dev.of_node,
1155 		of_dma_xlate_by_chan_id, dma_dev);
1156 	if (ret)
1157 		return ret;
1158 
1159 	ret = devm_add_action_or_reset(&pdev->dev, axi_dmac_free_dma_controller,
1160 				       pdev->dev.of_node);
1161 	if (ret)
1162 		return ret;
1163 
1164 	ret = devm_request_irq(&pdev->dev, dmac->irq, axi_dmac_interrupt_handler,
1165 			       IRQF_SHARED, dev_name(&pdev->dev), dmac);
1166 	if (ret)
1167 		return ret;
1168 
1169 	regmap = devm_regmap_init_mmio(&pdev->dev, dmac->base,
1170 		 &axi_dmac_regmap_config);
1171 
1172 	return PTR_ERR_OR_ZERO(regmap);
1173 }
1174 
1175 static const struct of_device_id axi_dmac_of_match_table[] = {
1176 	{ .compatible = "adi,axi-dmac-1.00.a" },
1177 	{ },
1178 };
1179 MODULE_DEVICE_TABLE(of, axi_dmac_of_match_table);
1180 
1181 static struct platform_driver axi_dmac_driver = {
1182 	.driver = {
1183 		.name = "dma-axi-dmac",
1184 		.of_match_table = axi_dmac_of_match_table,
1185 	},
1186 	.probe = axi_dmac_probe,
1187 };
1188 module_platform_driver(axi_dmac_driver);
1189 
1190 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
1191 MODULE_DESCRIPTION("DMA controller driver for the AXI-DMAC controller");
1192 MODULE_LICENSE("GPL v2");
1193