1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AMD Cryptographic Coprocessor (CCP) driver
4  *
5  * Copyright (C) 2016,2019 Advanced Micro Devices, Inc.
6  *
7  * Author: Gary R Hook <gary.hook@amd.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/dmaengine.h>
14 #include <linux/spinlock.h>
15 #include <linux/mutex.h>
16 #include <linux/ccp.h>
17 
18 #include "ccp-dev.h"
19 #include "../../dma/dmaengine.h"
20 
21 #define CCP_DMA_WIDTH(_mask)		\
22 ({					\
23 	u64 mask = _mask + 1;		\
24 	(mask == 0) ? 64 : fls64(mask);	\
25 })
26 
27 /* The CCP as a DMA provider can be configured for public or private
28  * channels. Default is specified in the vdata for the device (PCI ID).
29  * This module parameter will override for all channels on all devices:
30  *   dma_chan_attr = 0x2 to force all channels public
31  *                 = 0x1 to force all channels private
32  *                 = 0x0 to defer to the vdata setting
33  *                 = any other value: warning, revert to 0x0
34  */
35 static unsigned int dma_chan_attr = CCP_DMA_DFLT;
36 module_param(dma_chan_attr, uint, 0444);
37 MODULE_PARM_DESC(dma_chan_attr, "Set DMA channel visibility: 0 (default) = device defaults, 1 = make private, 2 = make public");
38 
39 static unsigned int dmaengine = 1;
40 module_param(dmaengine, uint, 0444);
41 MODULE_PARM_DESC(dmaengine, "Register services with the DMA subsystem (any non-zero value, default: 1)");
42 
43 static unsigned int ccp_get_dma_chan_attr(struct ccp_device *ccp)
44 {
45 	switch (dma_chan_attr) {
46 	case CCP_DMA_DFLT:
47 		return ccp->vdata->dma_chan_attr;
48 
49 	case CCP_DMA_PRIV:
50 		return DMA_PRIVATE;
51 
52 	case CCP_DMA_PUB:
53 		return 0;
54 
55 	default:
56 		dev_info_once(ccp->dev, "Invalid value for dma_chan_attr: %d\n",
57 			      dma_chan_attr);
58 		return ccp->vdata->dma_chan_attr;
59 	}
60 }
61 
62 static void ccp_free_cmd_resources(struct ccp_device *ccp,
63 				   struct list_head *list)
64 {
65 	struct ccp_dma_cmd *cmd, *ctmp;
66 
67 	list_for_each_entry_safe(cmd, ctmp, list, entry) {
68 		list_del(&cmd->entry);
69 		kmem_cache_free(ccp->dma_cmd_cache, cmd);
70 	}
71 }
72 
73 static void ccp_free_desc_resources(struct ccp_device *ccp,
74 				    struct list_head *list)
75 {
76 	struct ccp_dma_desc *desc, *dtmp;
77 
78 	list_for_each_entry_safe(desc, dtmp, list, entry) {
79 		ccp_free_cmd_resources(ccp, &desc->active);
80 		ccp_free_cmd_resources(ccp, &desc->pending);
81 
82 		list_del(&desc->entry);
83 		kmem_cache_free(ccp->dma_desc_cache, desc);
84 	}
85 }
86 
87 static void ccp_free_chan_resources(struct dma_chan *dma_chan)
88 {
89 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
90 						 dma_chan);
91 	unsigned long flags;
92 
93 	dev_dbg(chan->ccp->dev, "%s - chan=%p\n", __func__, chan);
94 
95 	spin_lock_irqsave(&chan->lock, flags);
96 
97 	ccp_free_desc_resources(chan->ccp, &chan->complete);
98 	ccp_free_desc_resources(chan->ccp, &chan->active);
99 	ccp_free_desc_resources(chan->ccp, &chan->pending);
100 	ccp_free_desc_resources(chan->ccp, &chan->created);
101 
102 	spin_unlock_irqrestore(&chan->lock, flags);
103 }
104 
105 static void ccp_cleanup_desc_resources(struct ccp_device *ccp,
106 				       struct list_head *list)
107 {
108 	struct ccp_dma_desc *desc, *dtmp;
109 
110 	list_for_each_entry_safe_reverse(desc, dtmp, list, entry) {
111 		if (!async_tx_test_ack(&desc->tx_desc))
112 			continue;
113 
114 		dev_dbg(ccp->dev, "%s - desc=%p\n", __func__, desc);
115 
116 		ccp_free_cmd_resources(ccp, &desc->active);
117 		ccp_free_cmd_resources(ccp, &desc->pending);
118 
119 		list_del(&desc->entry);
120 		kmem_cache_free(ccp->dma_desc_cache, desc);
121 	}
122 }
123 
124 static void ccp_do_cleanup(unsigned long data)
125 {
126 	struct ccp_dma_chan *chan = (struct ccp_dma_chan *)data;
127 	unsigned long flags;
128 
129 	dev_dbg(chan->ccp->dev, "%s - chan=%s\n", __func__,
130 		dma_chan_name(&chan->dma_chan));
131 
132 	spin_lock_irqsave(&chan->lock, flags);
133 
134 	ccp_cleanup_desc_resources(chan->ccp, &chan->complete);
135 
136 	spin_unlock_irqrestore(&chan->lock, flags);
137 }
138 
139 static int ccp_issue_next_cmd(struct ccp_dma_desc *desc)
140 {
141 	struct ccp_dma_cmd *cmd;
142 	int ret;
143 
144 	cmd = list_first_entry(&desc->pending, struct ccp_dma_cmd, entry);
145 	list_move(&cmd->entry, &desc->active);
146 
147 	dev_dbg(desc->ccp->dev, "%s - tx %d, cmd=%p\n", __func__,
148 		desc->tx_desc.cookie, cmd);
149 
150 	ret = ccp_enqueue_cmd(&cmd->ccp_cmd);
151 	if (!ret || (ret == -EINPROGRESS) || (ret == -EBUSY))
152 		return 0;
153 
154 	dev_dbg(desc->ccp->dev, "%s - error: ret=%d, tx %d, cmd=%p\n", __func__,
155 		ret, desc->tx_desc.cookie, cmd);
156 
157 	return ret;
158 }
159 
160 static void ccp_free_active_cmd(struct ccp_dma_desc *desc)
161 {
162 	struct ccp_dma_cmd *cmd;
163 
164 	cmd = list_first_entry_or_null(&desc->active, struct ccp_dma_cmd,
165 				       entry);
166 	if (!cmd)
167 		return;
168 
169 	dev_dbg(desc->ccp->dev, "%s - freeing tx %d cmd=%p\n",
170 		__func__, desc->tx_desc.cookie, cmd);
171 
172 	list_del(&cmd->entry);
173 	kmem_cache_free(desc->ccp->dma_cmd_cache, cmd);
174 }
175 
176 static struct ccp_dma_desc *__ccp_next_dma_desc(struct ccp_dma_chan *chan,
177 						struct ccp_dma_desc *desc)
178 {
179 	/* Move current DMA descriptor to the complete list */
180 	if (desc)
181 		list_move(&desc->entry, &chan->complete);
182 
183 	/* Get the next DMA descriptor on the active list */
184 	desc = list_first_entry_or_null(&chan->active, struct ccp_dma_desc,
185 					entry);
186 
187 	return desc;
188 }
189 
190 static struct ccp_dma_desc *ccp_handle_active_desc(struct ccp_dma_chan *chan,
191 						   struct ccp_dma_desc *desc)
192 {
193 	struct dma_async_tx_descriptor *tx_desc;
194 	unsigned long flags;
195 
196 	/* Loop over descriptors until one is found with commands */
197 	do {
198 		if (desc) {
199 			/* Remove the DMA command from the list and free it */
200 			ccp_free_active_cmd(desc);
201 
202 			if (!list_empty(&desc->pending)) {
203 				/* No errors, keep going */
204 				if (desc->status != DMA_ERROR)
205 					return desc;
206 
207 				/* Error, free remaining commands and move on */
208 				ccp_free_cmd_resources(desc->ccp,
209 						       &desc->pending);
210 			}
211 
212 			tx_desc = &desc->tx_desc;
213 		} else {
214 			tx_desc = NULL;
215 		}
216 
217 		spin_lock_irqsave(&chan->lock, flags);
218 
219 		if (desc) {
220 			if (desc->status != DMA_ERROR)
221 				desc->status = DMA_COMPLETE;
222 
223 			dev_dbg(desc->ccp->dev,
224 				"%s - tx %d complete, status=%u\n", __func__,
225 				desc->tx_desc.cookie, desc->status);
226 
227 			dma_cookie_complete(tx_desc);
228 			dma_descriptor_unmap(tx_desc);
229 		}
230 
231 		desc = __ccp_next_dma_desc(chan, desc);
232 
233 		spin_unlock_irqrestore(&chan->lock, flags);
234 
235 		if (tx_desc) {
236 			dmaengine_desc_get_callback_invoke(tx_desc, NULL);
237 
238 			dma_run_dependencies(tx_desc);
239 		}
240 	} while (desc);
241 
242 	return NULL;
243 }
244 
245 static struct ccp_dma_desc *__ccp_pending_to_active(struct ccp_dma_chan *chan)
246 {
247 	struct ccp_dma_desc *desc;
248 
249 	if (list_empty(&chan->pending))
250 		return NULL;
251 
252 	desc = list_empty(&chan->active)
253 		? list_first_entry(&chan->pending, struct ccp_dma_desc, entry)
254 		: NULL;
255 
256 	list_splice_tail_init(&chan->pending, &chan->active);
257 
258 	return desc;
259 }
260 
261 static void ccp_cmd_callback(void *data, int err)
262 {
263 	struct ccp_dma_desc *desc = data;
264 	struct ccp_dma_chan *chan;
265 	int ret;
266 
267 	if (err == -EINPROGRESS)
268 		return;
269 
270 	chan = container_of(desc->tx_desc.chan, struct ccp_dma_chan,
271 			    dma_chan);
272 
273 	dev_dbg(chan->ccp->dev, "%s - tx %d callback, err=%d\n",
274 		__func__, desc->tx_desc.cookie, err);
275 
276 	if (err)
277 		desc->status = DMA_ERROR;
278 
279 	while (true) {
280 		/* Check for DMA descriptor completion */
281 		desc = ccp_handle_active_desc(chan, desc);
282 
283 		/* Don't submit cmd if no descriptor or DMA is paused */
284 		if (!desc || (chan->status == DMA_PAUSED))
285 			break;
286 
287 		ret = ccp_issue_next_cmd(desc);
288 		if (!ret)
289 			break;
290 
291 		desc->status = DMA_ERROR;
292 	}
293 
294 	tasklet_schedule(&chan->cleanup_tasklet);
295 }
296 
297 static dma_cookie_t ccp_tx_submit(struct dma_async_tx_descriptor *tx_desc)
298 {
299 	struct ccp_dma_desc *desc = container_of(tx_desc, struct ccp_dma_desc,
300 						 tx_desc);
301 	struct ccp_dma_chan *chan;
302 	dma_cookie_t cookie;
303 	unsigned long flags;
304 
305 	chan = container_of(tx_desc->chan, struct ccp_dma_chan, dma_chan);
306 
307 	spin_lock_irqsave(&chan->lock, flags);
308 
309 	cookie = dma_cookie_assign(tx_desc);
310 	list_del(&desc->entry);
311 	list_add_tail(&desc->entry, &chan->pending);
312 
313 	spin_unlock_irqrestore(&chan->lock, flags);
314 
315 	dev_dbg(chan->ccp->dev, "%s - added tx descriptor %d to pending list\n",
316 		__func__, cookie);
317 
318 	return cookie;
319 }
320 
321 static struct ccp_dma_cmd *ccp_alloc_dma_cmd(struct ccp_dma_chan *chan)
322 {
323 	struct ccp_dma_cmd *cmd;
324 
325 	cmd = kmem_cache_alloc(chan->ccp->dma_cmd_cache, GFP_NOWAIT);
326 	if (cmd)
327 		memset(cmd, 0, sizeof(*cmd));
328 
329 	return cmd;
330 }
331 
332 static struct ccp_dma_desc *ccp_alloc_dma_desc(struct ccp_dma_chan *chan,
333 					       unsigned long flags)
334 {
335 	struct ccp_dma_desc *desc;
336 
337 	desc = kmem_cache_zalloc(chan->ccp->dma_desc_cache, GFP_NOWAIT);
338 	if (!desc)
339 		return NULL;
340 
341 	dma_async_tx_descriptor_init(&desc->tx_desc, &chan->dma_chan);
342 	desc->tx_desc.flags = flags;
343 	desc->tx_desc.tx_submit = ccp_tx_submit;
344 	desc->ccp = chan->ccp;
345 	INIT_LIST_HEAD(&desc->entry);
346 	INIT_LIST_HEAD(&desc->pending);
347 	INIT_LIST_HEAD(&desc->active);
348 	desc->status = DMA_IN_PROGRESS;
349 
350 	return desc;
351 }
352 
353 static struct ccp_dma_desc *ccp_create_desc(struct dma_chan *dma_chan,
354 					    struct scatterlist *dst_sg,
355 					    unsigned int dst_nents,
356 					    struct scatterlist *src_sg,
357 					    unsigned int src_nents,
358 					    unsigned long flags)
359 {
360 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
361 						 dma_chan);
362 	struct ccp_device *ccp = chan->ccp;
363 	struct ccp_dma_desc *desc;
364 	struct ccp_dma_cmd *cmd;
365 	struct ccp_cmd *ccp_cmd;
366 	struct ccp_passthru_nomap_engine *ccp_pt;
367 	unsigned int src_offset, src_len;
368 	unsigned int dst_offset, dst_len;
369 	unsigned int len;
370 	unsigned long sflags;
371 	size_t total_len;
372 
373 	if (!dst_sg || !src_sg)
374 		return NULL;
375 
376 	if (!dst_nents || !src_nents)
377 		return NULL;
378 
379 	desc = ccp_alloc_dma_desc(chan, flags);
380 	if (!desc)
381 		return NULL;
382 
383 	total_len = 0;
384 
385 	src_len = sg_dma_len(src_sg);
386 	src_offset = 0;
387 
388 	dst_len = sg_dma_len(dst_sg);
389 	dst_offset = 0;
390 
391 	while (true) {
392 		if (!src_len) {
393 			src_nents--;
394 			if (!src_nents)
395 				break;
396 
397 			src_sg = sg_next(src_sg);
398 			if (!src_sg)
399 				break;
400 
401 			src_len = sg_dma_len(src_sg);
402 			src_offset = 0;
403 			continue;
404 		}
405 
406 		if (!dst_len) {
407 			dst_nents--;
408 			if (!dst_nents)
409 				break;
410 
411 			dst_sg = sg_next(dst_sg);
412 			if (!dst_sg)
413 				break;
414 
415 			dst_len = sg_dma_len(dst_sg);
416 			dst_offset = 0;
417 			continue;
418 		}
419 
420 		len = min(dst_len, src_len);
421 
422 		cmd = ccp_alloc_dma_cmd(chan);
423 		if (!cmd)
424 			goto err;
425 
426 		ccp_cmd = &cmd->ccp_cmd;
427 		ccp_cmd->ccp = chan->ccp;
428 		ccp_pt = &ccp_cmd->u.passthru_nomap;
429 		ccp_cmd->flags = CCP_CMD_MAY_BACKLOG;
430 		ccp_cmd->flags |= CCP_CMD_PASSTHRU_NO_DMA_MAP;
431 		ccp_cmd->engine = CCP_ENGINE_PASSTHRU;
432 		ccp_pt->bit_mod = CCP_PASSTHRU_BITWISE_NOOP;
433 		ccp_pt->byte_swap = CCP_PASSTHRU_BYTESWAP_NOOP;
434 		ccp_pt->src_dma = sg_dma_address(src_sg) + src_offset;
435 		ccp_pt->dst_dma = sg_dma_address(dst_sg) + dst_offset;
436 		ccp_pt->src_len = len;
437 		ccp_pt->final = 1;
438 		ccp_cmd->callback = ccp_cmd_callback;
439 		ccp_cmd->data = desc;
440 
441 		list_add_tail(&cmd->entry, &desc->pending);
442 
443 		dev_dbg(ccp->dev,
444 			"%s - cmd=%p, src=%pad, dst=%pad, len=%llu\n", __func__,
445 			cmd, &ccp_pt->src_dma,
446 			&ccp_pt->dst_dma, ccp_pt->src_len);
447 
448 		total_len += len;
449 
450 		src_len -= len;
451 		src_offset += len;
452 
453 		dst_len -= len;
454 		dst_offset += len;
455 	}
456 
457 	desc->len = total_len;
458 
459 	if (list_empty(&desc->pending))
460 		goto err;
461 
462 	dev_dbg(ccp->dev, "%s - desc=%p\n", __func__, desc);
463 
464 	spin_lock_irqsave(&chan->lock, sflags);
465 
466 	list_add_tail(&desc->entry, &chan->created);
467 
468 	spin_unlock_irqrestore(&chan->lock, sflags);
469 
470 	return desc;
471 
472 err:
473 	ccp_free_cmd_resources(ccp, &desc->pending);
474 	kmem_cache_free(ccp->dma_desc_cache, desc);
475 
476 	return NULL;
477 }
478 
479 static struct dma_async_tx_descriptor *ccp_prep_dma_memcpy(
480 	struct dma_chan *dma_chan, dma_addr_t dst, dma_addr_t src, size_t len,
481 	unsigned long flags)
482 {
483 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
484 						 dma_chan);
485 	struct ccp_dma_desc *desc;
486 	struct scatterlist dst_sg, src_sg;
487 
488 	dev_dbg(chan->ccp->dev,
489 		"%s - src=%pad, dst=%pad, len=%zu, flags=%#lx\n",
490 		__func__, &src, &dst, len, flags);
491 
492 	sg_init_table(&dst_sg, 1);
493 	sg_dma_address(&dst_sg) = dst;
494 	sg_dma_len(&dst_sg) = len;
495 
496 	sg_init_table(&src_sg, 1);
497 	sg_dma_address(&src_sg) = src;
498 	sg_dma_len(&src_sg) = len;
499 
500 	desc = ccp_create_desc(dma_chan, &dst_sg, 1, &src_sg, 1, flags);
501 	if (!desc)
502 		return NULL;
503 
504 	return &desc->tx_desc;
505 }
506 
507 static struct dma_async_tx_descriptor *ccp_prep_dma_interrupt(
508 	struct dma_chan *dma_chan, unsigned long flags)
509 {
510 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
511 						 dma_chan);
512 	struct ccp_dma_desc *desc;
513 
514 	desc = ccp_alloc_dma_desc(chan, flags);
515 	if (!desc)
516 		return NULL;
517 
518 	return &desc->tx_desc;
519 }
520 
521 static void ccp_issue_pending(struct dma_chan *dma_chan)
522 {
523 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
524 						 dma_chan);
525 	struct ccp_dma_desc *desc;
526 	unsigned long flags;
527 
528 	dev_dbg(chan->ccp->dev, "%s\n", __func__);
529 
530 	spin_lock_irqsave(&chan->lock, flags);
531 
532 	desc = __ccp_pending_to_active(chan);
533 
534 	spin_unlock_irqrestore(&chan->lock, flags);
535 
536 	/* If there was nothing active, start processing */
537 	if (desc)
538 		ccp_cmd_callback(desc, 0);
539 }
540 
541 static enum dma_status ccp_tx_status(struct dma_chan *dma_chan,
542 				     dma_cookie_t cookie,
543 				     struct dma_tx_state *state)
544 {
545 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
546 						 dma_chan);
547 	struct ccp_dma_desc *desc;
548 	enum dma_status ret;
549 	unsigned long flags;
550 
551 	if (chan->status == DMA_PAUSED) {
552 		ret = DMA_PAUSED;
553 		goto out;
554 	}
555 
556 	ret = dma_cookie_status(dma_chan, cookie, state);
557 	if (ret == DMA_COMPLETE) {
558 		spin_lock_irqsave(&chan->lock, flags);
559 
560 		/* Get status from complete chain, if still there */
561 		list_for_each_entry(desc, &chan->complete, entry) {
562 			if (desc->tx_desc.cookie != cookie)
563 				continue;
564 
565 			ret = desc->status;
566 			break;
567 		}
568 
569 		spin_unlock_irqrestore(&chan->lock, flags);
570 	}
571 
572 out:
573 	dev_dbg(chan->ccp->dev, "%s - %u\n", __func__, ret);
574 
575 	return ret;
576 }
577 
578 static int ccp_pause(struct dma_chan *dma_chan)
579 {
580 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
581 						 dma_chan);
582 
583 	chan->status = DMA_PAUSED;
584 
585 	/*TODO: Wait for active DMA to complete before returning? */
586 
587 	return 0;
588 }
589 
590 static int ccp_resume(struct dma_chan *dma_chan)
591 {
592 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
593 						 dma_chan);
594 	struct ccp_dma_desc *desc;
595 	unsigned long flags;
596 
597 	spin_lock_irqsave(&chan->lock, flags);
598 
599 	desc = list_first_entry_or_null(&chan->active, struct ccp_dma_desc,
600 					entry);
601 
602 	spin_unlock_irqrestore(&chan->lock, flags);
603 
604 	/* Indicate the channel is running again */
605 	chan->status = DMA_IN_PROGRESS;
606 
607 	/* If there was something active, re-start */
608 	if (desc)
609 		ccp_cmd_callback(desc, 0);
610 
611 	return 0;
612 }
613 
614 static int ccp_terminate_all(struct dma_chan *dma_chan)
615 {
616 	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
617 						 dma_chan);
618 	unsigned long flags;
619 
620 	dev_dbg(chan->ccp->dev, "%s\n", __func__);
621 
622 	/*TODO: Wait for active DMA to complete before continuing */
623 
624 	spin_lock_irqsave(&chan->lock, flags);
625 
626 	/*TODO: Purge the complete list? */
627 	ccp_free_desc_resources(chan->ccp, &chan->active);
628 	ccp_free_desc_resources(chan->ccp, &chan->pending);
629 	ccp_free_desc_resources(chan->ccp, &chan->created);
630 
631 	spin_unlock_irqrestore(&chan->lock, flags);
632 
633 	return 0;
634 }
635 
636 int ccp_dmaengine_register(struct ccp_device *ccp)
637 {
638 	struct ccp_dma_chan *chan;
639 	struct dma_device *dma_dev = &ccp->dma_dev;
640 	struct dma_chan *dma_chan;
641 	char *dma_cmd_cache_name;
642 	char *dma_desc_cache_name;
643 	unsigned int i;
644 	int ret;
645 
646 	if (!dmaengine)
647 		return 0;
648 
649 	ccp->ccp_dma_chan = devm_kcalloc(ccp->dev, ccp->cmd_q_count,
650 					 sizeof(*(ccp->ccp_dma_chan)),
651 					 GFP_KERNEL);
652 	if (!ccp->ccp_dma_chan)
653 		return -ENOMEM;
654 
655 	dma_cmd_cache_name = devm_kasprintf(ccp->dev, GFP_KERNEL,
656 					    "%s-dmaengine-cmd-cache",
657 					    ccp->name);
658 	if (!dma_cmd_cache_name)
659 		return -ENOMEM;
660 
661 	ccp->dma_cmd_cache = kmem_cache_create(dma_cmd_cache_name,
662 					       sizeof(struct ccp_dma_cmd),
663 					       sizeof(void *),
664 					       SLAB_HWCACHE_ALIGN, NULL);
665 	if (!ccp->dma_cmd_cache)
666 		return -ENOMEM;
667 
668 	dma_desc_cache_name = devm_kasprintf(ccp->dev, GFP_KERNEL,
669 					     "%s-dmaengine-desc-cache",
670 					     ccp->name);
671 	if (!dma_desc_cache_name) {
672 		ret = -ENOMEM;
673 		goto err_cache;
674 	}
675 
676 	ccp->dma_desc_cache = kmem_cache_create(dma_desc_cache_name,
677 						sizeof(struct ccp_dma_desc),
678 						sizeof(void *),
679 						SLAB_HWCACHE_ALIGN, NULL);
680 	if (!ccp->dma_desc_cache) {
681 		ret = -ENOMEM;
682 		goto err_cache;
683 	}
684 
685 	dma_dev->dev = ccp->dev;
686 	dma_dev->src_addr_widths = CCP_DMA_WIDTH(dma_get_mask(ccp->dev));
687 	dma_dev->dst_addr_widths = CCP_DMA_WIDTH(dma_get_mask(ccp->dev));
688 	dma_dev->directions = DMA_MEM_TO_MEM;
689 	dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
690 	dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
691 	dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask);
692 
693 	/* The DMA channels for this device can be set to public or private,
694 	 * and overridden by the module parameter dma_chan_attr.
695 	 * Default: according to the value in vdata (dma_chan_attr=0)
696 	 * dma_chan_attr=0x1: all channels private (override vdata)
697 	 * dma_chan_attr=0x2: all channels public (override vdata)
698 	 */
699 	if (ccp_get_dma_chan_attr(ccp) == DMA_PRIVATE)
700 		dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask);
701 
702 	INIT_LIST_HEAD(&dma_dev->channels);
703 	for (i = 0; i < ccp->cmd_q_count; i++) {
704 		chan = ccp->ccp_dma_chan + i;
705 		dma_chan = &chan->dma_chan;
706 
707 		chan->ccp = ccp;
708 
709 		spin_lock_init(&chan->lock);
710 		INIT_LIST_HEAD(&chan->created);
711 		INIT_LIST_HEAD(&chan->pending);
712 		INIT_LIST_HEAD(&chan->active);
713 		INIT_LIST_HEAD(&chan->complete);
714 
715 		tasklet_init(&chan->cleanup_tasklet, ccp_do_cleanup,
716 			     (unsigned long)chan);
717 
718 		dma_chan->device = dma_dev;
719 		dma_cookie_init(dma_chan);
720 
721 		list_add_tail(&dma_chan->device_node, &dma_dev->channels);
722 	}
723 
724 	dma_dev->device_free_chan_resources = ccp_free_chan_resources;
725 	dma_dev->device_prep_dma_memcpy = ccp_prep_dma_memcpy;
726 	dma_dev->device_prep_dma_interrupt = ccp_prep_dma_interrupt;
727 	dma_dev->device_issue_pending = ccp_issue_pending;
728 	dma_dev->device_tx_status = ccp_tx_status;
729 	dma_dev->device_pause = ccp_pause;
730 	dma_dev->device_resume = ccp_resume;
731 	dma_dev->device_terminate_all = ccp_terminate_all;
732 
733 	ret = dma_async_device_register(dma_dev);
734 	if (ret)
735 		goto err_reg;
736 
737 	return 0;
738 
739 err_reg:
740 	kmem_cache_destroy(ccp->dma_desc_cache);
741 
742 err_cache:
743 	kmem_cache_destroy(ccp->dma_cmd_cache);
744 
745 	return ret;
746 }
747 
748 void ccp_dmaengine_unregister(struct ccp_device *ccp)
749 {
750 	struct dma_device *dma_dev = &ccp->dma_dev;
751 
752 	if (!dmaengine)
753 		return;
754 
755 	dma_async_device_unregister(dma_dev);
756 
757 	kmem_cache_destroy(ccp->dma_desc_cache);
758 	kmem_cache_destroy(ccp->dma_cmd_cache);
759 }
760