xref: /openbmc/linux/drivers/dma/bcm-sba-raid.c (revision e3b9f1e8)
1 /*
2  * Copyright (C) 2017 Broadcom
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation version 2.
7  *
8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9  * kind, whether express or implied; without even the implied warranty
10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 /*
15  * Broadcom SBA RAID Driver
16  *
17  * The Broadcom stream buffer accelerator (SBA) provides offloading
18  * capabilities for RAID operations. The SBA offload engine is accessible
19  * via Broadcom SoC specific ring manager. Two or more offload engines
20  * can share same Broadcom SoC specific ring manager due to this Broadcom
21  * SoC specific ring manager driver is implemented as a mailbox controller
22  * driver and offload engine drivers are implemented as mallbox clients.
23  *
24  * Typically, Broadcom SoC specific ring manager will implement larger
25  * number of hardware rings over one or more SBA hardware devices. By
26  * design, the internal buffer size of SBA hardware device is limited
27  * but all offload operations supported by SBA can be broken down into
28  * multiple small size requests and executed parallely on multiple SBA
29  * hardware devices for achieving high through-put.
30  *
31  * The Broadcom SBA RAID driver does not require any register programming
32  * except submitting request to SBA hardware device via mailbox channels.
33  * This driver implements a DMA device with one DMA channel using a single
34  * mailbox channel provided by Broadcom SoC specific ring manager driver.
35  * For having more SBA DMA channels, we can create more SBA device nodes
36  * in Broadcom SoC specific DTS based on number of hardware rings supported
37  * by Broadcom SoC ring manager.
38  */
39 
40 #include <linux/bitops.h>
41 #include <linux/debugfs.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/dmaengine.h>
44 #include <linux/list.h>
45 #include <linux/mailbox_client.h>
46 #include <linux/mailbox/brcm-message.h>
47 #include <linux/module.h>
48 #include <linux/of_device.h>
49 #include <linux/slab.h>
50 #include <linux/raid/pq.h>
51 
52 #include "dmaengine.h"
53 
54 /* ====== Driver macros and defines ===== */
55 
56 #define SBA_TYPE_SHIFT					48
57 #define SBA_TYPE_MASK					GENMASK(1, 0)
58 #define SBA_TYPE_A					0x0
59 #define SBA_TYPE_B					0x2
60 #define SBA_TYPE_C					0x3
61 #define SBA_USER_DEF_SHIFT				32
62 #define SBA_USER_DEF_MASK				GENMASK(15, 0)
63 #define SBA_R_MDATA_SHIFT				24
64 #define SBA_R_MDATA_MASK				GENMASK(7, 0)
65 #define SBA_C_MDATA_MS_SHIFT				18
66 #define SBA_C_MDATA_MS_MASK				GENMASK(1, 0)
67 #define SBA_INT_SHIFT					17
68 #define SBA_INT_MASK					BIT(0)
69 #define SBA_RESP_SHIFT					16
70 #define SBA_RESP_MASK					BIT(0)
71 #define SBA_C_MDATA_SHIFT				8
72 #define SBA_C_MDATA_MASK				GENMASK(7, 0)
73 #define SBA_C_MDATA_BNUMx_SHIFT(__bnum)			(2 * (__bnum))
74 #define SBA_C_MDATA_BNUMx_MASK				GENMASK(1, 0)
75 #define SBA_C_MDATA_DNUM_SHIFT				5
76 #define SBA_C_MDATA_DNUM_MASK				GENMASK(4, 0)
77 #define SBA_C_MDATA_LS(__v)				((__v) & 0xff)
78 #define SBA_C_MDATA_MS(__v)				(((__v) >> 8) & 0x3)
79 #define SBA_CMD_SHIFT					0
80 #define SBA_CMD_MASK					GENMASK(3, 0)
81 #define SBA_CMD_ZERO_BUFFER				0x4
82 #define SBA_CMD_ZERO_ALL_BUFFERS			0x8
83 #define SBA_CMD_LOAD_BUFFER				0x9
84 #define SBA_CMD_XOR					0xa
85 #define SBA_CMD_GALOIS_XOR				0xb
86 #define SBA_CMD_WRITE_BUFFER				0xc
87 #define SBA_CMD_GALOIS					0xe
88 
89 #define SBA_MAX_REQ_PER_MBOX_CHANNEL			8192
90 #define SBA_MAX_MSG_SEND_PER_MBOX_CHANNEL		8
91 
92 /* Driver helper macros */
93 #define to_sba_request(tx)		\
94 	container_of(tx, struct sba_request, tx)
95 #define to_sba_device(dchan)		\
96 	container_of(dchan, struct sba_device, dma_chan)
97 
98 /* ===== Driver data structures ===== */
99 
100 enum sba_request_flags {
101 	SBA_REQUEST_STATE_FREE		= 0x001,
102 	SBA_REQUEST_STATE_ALLOCED	= 0x002,
103 	SBA_REQUEST_STATE_PENDING	= 0x004,
104 	SBA_REQUEST_STATE_ACTIVE	= 0x008,
105 	SBA_REQUEST_STATE_ABORTED	= 0x010,
106 	SBA_REQUEST_STATE_MASK		= 0x0ff,
107 	SBA_REQUEST_FENCE		= 0x100,
108 };
109 
110 struct sba_request {
111 	/* Global state */
112 	struct list_head node;
113 	struct sba_device *sba;
114 	u32 flags;
115 	/* Chained requests management */
116 	struct sba_request *first;
117 	struct list_head next;
118 	atomic_t next_pending_count;
119 	/* BRCM message data */
120 	struct brcm_message msg;
121 	struct dma_async_tx_descriptor tx;
122 	/* SBA commands */
123 	struct brcm_sba_command cmds[0];
124 };
125 
126 enum sba_version {
127 	SBA_VER_1 = 0,
128 	SBA_VER_2
129 };
130 
131 struct sba_device {
132 	/* Underlying device */
133 	struct device *dev;
134 	/* DT configuration parameters */
135 	enum sba_version ver;
136 	/* Derived configuration parameters */
137 	u32 max_req;
138 	u32 hw_buf_size;
139 	u32 hw_resp_size;
140 	u32 max_pq_coefs;
141 	u32 max_pq_srcs;
142 	u32 max_cmd_per_req;
143 	u32 max_xor_srcs;
144 	u32 max_resp_pool_size;
145 	u32 max_cmds_pool_size;
146 	/* Maibox client and Mailbox channels */
147 	struct mbox_client client;
148 	struct mbox_chan *mchan;
149 	struct device *mbox_dev;
150 	/* DMA device and DMA channel */
151 	struct dma_device dma_dev;
152 	struct dma_chan dma_chan;
153 	/* DMA channel resources */
154 	void *resp_base;
155 	dma_addr_t resp_dma_base;
156 	void *cmds_base;
157 	dma_addr_t cmds_dma_base;
158 	spinlock_t reqs_lock;
159 	bool reqs_fence;
160 	struct list_head reqs_alloc_list;
161 	struct list_head reqs_pending_list;
162 	struct list_head reqs_active_list;
163 	struct list_head reqs_aborted_list;
164 	struct list_head reqs_free_list;
165 	/* DebugFS directory entries */
166 	struct dentry *root;
167 	struct dentry *stats;
168 };
169 
170 /* ====== Command helper routines ===== */
171 
172 static inline u64 __pure sba_cmd_enc(u64 cmd, u32 val, u32 shift, u32 mask)
173 {
174 	cmd &= ~((u64)mask << shift);
175 	cmd |= ((u64)(val & mask) << shift);
176 	return cmd;
177 }
178 
179 static inline u32 __pure sba_cmd_load_c_mdata(u32 b0)
180 {
181 	return b0 & SBA_C_MDATA_BNUMx_MASK;
182 }
183 
184 static inline u32 __pure sba_cmd_write_c_mdata(u32 b0)
185 {
186 	return b0 & SBA_C_MDATA_BNUMx_MASK;
187 }
188 
189 static inline u32 __pure sba_cmd_xor_c_mdata(u32 b1, u32 b0)
190 {
191 	return (b0 & SBA_C_MDATA_BNUMx_MASK) |
192 	       ((b1 & SBA_C_MDATA_BNUMx_MASK) << SBA_C_MDATA_BNUMx_SHIFT(1));
193 }
194 
195 static inline u32 __pure sba_cmd_pq_c_mdata(u32 d, u32 b1, u32 b0)
196 {
197 	return (b0 & SBA_C_MDATA_BNUMx_MASK) |
198 	       ((b1 & SBA_C_MDATA_BNUMx_MASK) << SBA_C_MDATA_BNUMx_SHIFT(1)) |
199 	       ((d & SBA_C_MDATA_DNUM_MASK) << SBA_C_MDATA_DNUM_SHIFT);
200 }
201 
202 /* ====== General helper routines ===== */
203 
204 static struct sba_request *sba_alloc_request(struct sba_device *sba)
205 {
206 	bool found = false;
207 	unsigned long flags;
208 	struct sba_request *req = NULL;
209 
210 	spin_lock_irqsave(&sba->reqs_lock, flags);
211 	list_for_each_entry(req, &sba->reqs_free_list, node) {
212 		if (async_tx_test_ack(&req->tx)) {
213 			list_move_tail(&req->node, &sba->reqs_alloc_list);
214 			found = true;
215 			break;
216 		}
217 	}
218 	spin_unlock_irqrestore(&sba->reqs_lock, flags);
219 
220 	if (!found) {
221 		/*
222 		 * We have no more free requests so, we peek
223 		 * mailbox channels hoping few active requests
224 		 * would have completed which will create more
225 		 * room for new requests.
226 		 */
227 		mbox_client_peek_data(sba->mchan);
228 		return NULL;
229 	}
230 
231 	req->flags = SBA_REQUEST_STATE_ALLOCED;
232 	req->first = req;
233 	INIT_LIST_HEAD(&req->next);
234 	atomic_set(&req->next_pending_count, 1);
235 
236 	dma_async_tx_descriptor_init(&req->tx, &sba->dma_chan);
237 	async_tx_ack(&req->tx);
238 
239 	return req;
240 }
241 
242 /* Note: Must be called with sba->reqs_lock held */
243 static void _sba_pending_request(struct sba_device *sba,
244 				 struct sba_request *req)
245 {
246 	lockdep_assert_held(&sba->reqs_lock);
247 	req->flags &= ~SBA_REQUEST_STATE_MASK;
248 	req->flags |= SBA_REQUEST_STATE_PENDING;
249 	list_move_tail(&req->node, &sba->reqs_pending_list);
250 	if (list_empty(&sba->reqs_active_list))
251 		sba->reqs_fence = false;
252 }
253 
254 /* Note: Must be called with sba->reqs_lock held */
255 static bool _sba_active_request(struct sba_device *sba,
256 				struct sba_request *req)
257 {
258 	lockdep_assert_held(&sba->reqs_lock);
259 	if (list_empty(&sba->reqs_active_list))
260 		sba->reqs_fence = false;
261 	if (sba->reqs_fence)
262 		return false;
263 	req->flags &= ~SBA_REQUEST_STATE_MASK;
264 	req->flags |= SBA_REQUEST_STATE_ACTIVE;
265 	list_move_tail(&req->node, &sba->reqs_active_list);
266 	if (req->flags & SBA_REQUEST_FENCE)
267 		sba->reqs_fence = true;
268 	return true;
269 }
270 
271 /* Note: Must be called with sba->reqs_lock held */
272 static void _sba_abort_request(struct sba_device *sba,
273 			       struct sba_request *req)
274 {
275 	lockdep_assert_held(&sba->reqs_lock);
276 	req->flags &= ~SBA_REQUEST_STATE_MASK;
277 	req->flags |= SBA_REQUEST_STATE_ABORTED;
278 	list_move_tail(&req->node, &sba->reqs_aborted_list);
279 	if (list_empty(&sba->reqs_active_list))
280 		sba->reqs_fence = false;
281 }
282 
283 /* Note: Must be called with sba->reqs_lock held */
284 static void _sba_free_request(struct sba_device *sba,
285 			      struct sba_request *req)
286 {
287 	lockdep_assert_held(&sba->reqs_lock);
288 	req->flags &= ~SBA_REQUEST_STATE_MASK;
289 	req->flags |= SBA_REQUEST_STATE_FREE;
290 	list_move_tail(&req->node, &sba->reqs_free_list);
291 	if (list_empty(&sba->reqs_active_list))
292 		sba->reqs_fence = false;
293 }
294 
295 static void sba_free_chained_requests(struct sba_request *req)
296 {
297 	unsigned long flags;
298 	struct sba_request *nreq;
299 	struct sba_device *sba = req->sba;
300 
301 	spin_lock_irqsave(&sba->reqs_lock, flags);
302 
303 	_sba_free_request(sba, req);
304 	list_for_each_entry(nreq, &req->next, next)
305 		_sba_free_request(sba, nreq);
306 
307 	spin_unlock_irqrestore(&sba->reqs_lock, flags);
308 }
309 
310 static void sba_chain_request(struct sba_request *first,
311 			      struct sba_request *req)
312 {
313 	unsigned long flags;
314 	struct sba_device *sba = req->sba;
315 
316 	spin_lock_irqsave(&sba->reqs_lock, flags);
317 
318 	list_add_tail(&req->next, &first->next);
319 	req->first = first;
320 	atomic_inc(&first->next_pending_count);
321 
322 	spin_unlock_irqrestore(&sba->reqs_lock, flags);
323 }
324 
325 static void sba_cleanup_nonpending_requests(struct sba_device *sba)
326 {
327 	unsigned long flags;
328 	struct sba_request *req, *req1;
329 
330 	spin_lock_irqsave(&sba->reqs_lock, flags);
331 
332 	/* Freeup all alloced request */
333 	list_for_each_entry_safe(req, req1, &sba->reqs_alloc_list, node)
334 		_sba_free_request(sba, req);
335 
336 	/* Set all active requests as aborted */
337 	list_for_each_entry_safe(req, req1, &sba->reqs_active_list, node)
338 		_sba_abort_request(sba, req);
339 
340 	/*
341 	 * Note: We expect that aborted request will be eventually
342 	 * freed by sba_receive_message()
343 	 */
344 
345 	spin_unlock_irqrestore(&sba->reqs_lock, flags);
346 }
347 
348 static void sba_cleanup_pending_requests(struct sba_device *sba)
349 {
350 	unsigned long flags;
351 	struct sba_request *req, *req1;
352 
353 	spin_lock_irqsave(&sba->reqs_lock, flags);
354 
355 	/* Freeup all pending request */
356 	list_for_each_entry_safe(req, req1, &sba->reqs_pending_list, node)
357 		_sba_free_request(sba, req);
358 
359 	spin_unlock_irqrestore(&sba->reqs_lock, flags);
360 }
361 
362 static int sba_send_mbox_request(struct sba_device *sba,
363 				 struct sba_request *req)
364 {
365 	int ret = 0;
366 
367 	/* Send message for the request */
368 	req->msg.error = 0;
369 	ret = mbox_send_message(sba->mchan, &req->msg);
370 	if (ret < 0) {
371 		dev_err(sba->dev, "send message failed with error %d", ret);
372 		return ret;
373 	}
374 
375 	/* Check error returned by mailbox controller */
376 	ret = req->msg.error;
377 	if (ret < 0) {
378 		dev_err(sba->dev, "message error %d", ret);
379 	}
380 
381 	/* Signal txdone for mailbox channel */
382 	mbox_client_txdone(sba->mchan, ret);
383 
384 	return ret;
385 }
386 
387 /* Note: Must be called with sba->reqs_lock held */
388 static void _sba_process_pending_requests(struct sba_device *sba)
389 {
390 	int ret;
391 	u32 count;
392 	struct sba_request *req;
393 
394 	/* Process few pending requests */
395 	count = SBA_MAX_MSG_SEND_PER_MBOX_CHANNEL;
396 	while (!list_empty(&sba->reqs_pending_list) && count) {
397 		/* Get the first pending request */
398 		req = list_first_entry(&sba->reqs_pending_list,
399 				       struct sba_request, node);
400 
401 		/* Try to make request active */
402 		if (!_sba_active_request(sba, req))
403 			break;
404 
405 		/* Send request to mailbox channel */
406 		ret = sba_send_mbox_request(sba, req);
407 		if (ret < 0) {
408 			_sba_pending_request(sba, req);
409 			break;
410 		}
411 
412 		count--;
413 	}
414 }
415 
416 static void sba_process_received_request(struct sba_device *sba,
417 					 struct sba_request *req)
418 {
419 	unsigned long flags;
420 	struct dma_async_tx_descriptor *tx;
421 	struct sba_request *nreq, *first = req->first;
422 
423 	/* Process only after all chained requests are received */
424 	if (!atomic_dec_return(&first->next_pending_count)) {
425 		tx = &first->tx;
426 
427 		WARN_ON(tx->cookie < 0);
428 		if (tx->cookie > 0) {
429 			spin_lock_irqsave(&sba->reqs_lock, flags);
430 			dma_cookie_complete(tx);
431 			spin_unlock_irqrestore(&sba->reqs_lock, flags);
432 			dmaengine_desc_get_callback_invoke(tx, NULL);
433 			dma_descriptor_unmap(tx);
434 			tx->callback = NULL;
435 			tx->callback_result = NULL;
436 		}
437 
438 		dma_run_dependencies(tx);
439 
440 		spin_lock_irqsave(&sba->reqs_lock, flags);
441 
442 		/* Free all requests chained to first request */
443 		list_for_each_entry(nreq, &first->next, next)
444 			_sba_free_request(sba, nreq);
445 		INIT_LIST_HEAD(&first->next);
446 
447 		/* Free the first request */
448 		_sba_free_request(sba, first);
449 
450 		/* Process pending requests */
451 		_sba_process_pending_requests(sba);
452 
453 		spin_unlock_irqrestore(&sba->reqs_lock, flags);
454 	}
455 }
456 
457 static void sba_write_stats_in_seqfile(struct sba_device *sba,
458 				       struct seq_file *file)
459 {
460 	unsigned long flags;
461 	struct sba_request *req;
462 	u32 free_count = 0, alloced_count = 0;
463 	u32 pending_count = 0, active_count = 0, aborted_count = 0;
464 
465 	spin_lock_irqsave(&sba->reqs_lock, flags);
466 
467 	list_for_each_entry(req, &sba->reqs_free_list, node)
468 		if (async_tx_test_ack(&req->tx))
469 			free_count++;
470 
471 	list_for_each_entry(req, &sba->reqs_alloc_list, node)
472 		alloced_count++;
473 
474 	list_for_each_entry(req, &sba->reqs_pending_list, node)
475 		pending_count++;
476 
477 	list_for_each_entry(req, &sba->reqs_active_list, node)
478 		active_count++;
479 
480 	list_for_each_entry(req, &sba->reqs_aborted_list, node)
481 		aborted_count++;
482 
483 	spin_unlock_irqrestore(&sba->reqs_lock, flags);
484 
485 	seq_printf(file, "maximum requests   = %d\n", sba->max_req);
486 	seq_printf(file, "free requests      = %d\n", free_count);
487 	seq_printf(file, "alloced requests   = %d\n", alloced_count);
488 	seq_printf(file, "pending requests   = %d\n", pending_count);
489 	seq_printf(file, "active requests    = %d\n", active_count);
490 	seq_printf(file, "aborted requests   = %d\n", aborted_count);
491 }
492 
493 /* ====== DMAENGINE callbacks ===== */
494 
495 static void sba_free_chan_resources(struct dma_chan *dchan)
496 {
497 	/*
498 	 * Channel resources are pre-alloced so we just free-up
499 	 * whatever we can so that we can re-use pre-alloced
500 	 * channel resources next time.
501 	 */
502 	sba_cleanup_nonpending_requests(to_sba_device(dchan));
503 }
504 
505 static int sba_device_terminate_all(struct dma_chan *dchan)
506 {
507 	/* Cleanup all pending requests */
508 	sba_cleanup_pending_requests(to_sba_device(dchan));
509 
510 	return 0;
511 }
512 
513 static void sba_issue_pending(struct dma_chan *dchan)
514 {
515 	unsigned long flags;
516 	struct sba_device *sba = to_sba_device(dchan);
517 
518 	/* Process pending requests */
519 	spin_lock_irqsave(&sba->reqs_lock, flags);
520 	_sba_process_pending_requests(sba);
521 	spin_unlock_irqrestore(&sba->reqs_lock, flags);
522 }
523 
524 static dma_cookie_t sba_tx_submit(struct dma_async_tx_descriptor *tx)
525 {
526 	unsigned long flags;
527 	dma_cookie_t cookie;
528 	struct sba_device *sba;
529 	struct sba_request *req, *nreq;
530 
531 	if (unlikely(!tx))
532 		return -EINVAL;
533 
534 	sba = to_sba_device(tx->chan);
535 	req = to_sba_request(tx);
536 
537 	/* Assign cookie and mark all chained requests pending */
538 	spin_lock_irqsave(&sba->reqs_lock, flags);
539 	cookie = dma_cookie_assign(tx);
540 	_sba_pending_request(sba, req);
541 	list_for_each_entry(nreq, &req->next, next)
542 		_sba_pending_request(sba, nreq);
543 	spin_unlock_irqrestore(&sba->reqs_lock, flags);
544 
545 	return cookie;
546 }
547 
548 static enum dma_status sba_tx_status(struct dma_chan *dchan,
549 				     dma_cookie_t cookie,
550 				     struct dma_tx_state *txstate)
551 {
552 	enum dma_status ret;
553 	struct sba_device *sba = to_sba_device(dchan);
554 
555 	ret = dma_cookie_status(dchan, cookie, txstate);
556 	if (ret == DMA_COMPLETE)
557 		return ret;
558 
559 	mbox_client_peek_data(sba->mchan);
560 
561 	return dma_cookie_status(dchan, cookie, txstate);
562 }
563 
564 static void sba_fillup_interrupt_msg(struct sba_request *req,
565 				     struct brcm_sba_command *cmds,
566 				     struct brcm_message *msg)
567 {
568 	u64 cmd;
569 	u32 c_mdata;
570 	dma_addr_t resp_dma = req->tx.phys;
571 	struct brcm_sba_command *cmdsp = cmds;
572 
573 	/* Type-B command to load dummy data into buf0 */
574 	cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
575 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
576 	cmd = sba_cmd_enc(cmd, req->sba->hw_resp_size,
577 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
578 	c_mdata = sba_cmd_load_c_mdata(0);
579 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
580 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
581 	cmd = sba_cmd_enc(cmd, SBA_CMD_LOAD_BUFFER,
582 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
583 	cmdsp->cmd = cmd;
584 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
585 	cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
586 	cmdsp->data = resp_dma;
587 	cmdsp->data_len = req->sba->hw_resp_size;
588 	cmdsp++;
589 
590 	/* Type-A command to write buf0 to dummy location */
591 	cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
592 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
593 	cmd = sba_cmd_enc(cmd, req->sba->hw_resp_size,
594 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
595 	cmd = sba_cmd_enc(cmd, 0x1,
596 			  SBA_RESP_SHIFT, SBA_RESP_MASK);
597 	c_mdata = sba_cmd_write_c_mdata(0);
598 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
599 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
600 	cmd = sba_cmd_enc(cmd, SBA_CMD_WRITE_BUFFER,
601 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
602 	cmdsp->cmd = cmd;
603 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
604 	cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
605 	if (req->sba->hw_resp_size) {
606 		cmdsp->flags |= BRCM_SBA_CMD_HAS_RESP;
607 		cmdsp->resp = resp_dma;
608 		cmdsp->resp_len = req->sba->hw_resp_size;
609 	}
610 	cmdsp->flags |= BRCM_SBA_CMD_HAS_OUTPUT;
611 	cmdsp->data = resp_dma;
612 	cmdsp->data_len = req->sba->hw_resp_size;
613 	cmdsp++;
614 
615 	/* Fillup brcm_message */
616 	msg->type = BRCM_MESSAGE_SBA;
617 	msg->sba.cmds = cmds;
618 	msg->sba.cmds_count = cmdsp - cmds;
619 	msg->ctx = req;
620 	msg->error = 0;
621 }
622 
623 static struct dma_async_tx_descriptor *
624 sba_prep_dma_interrupt(struct dma_chan *dchan, unsigned long flags)
625 {
626 	struct sba_request *req = NULL;
627 	struct sba_device *sba = to_sba_device(dchan);
628 
629 	/* Alloc new request */
630 	req = sba_alloc_request(sba);
631 	if (!req)
632 		return NULL;
633 
634 	/*
635 	 * Force fence so that no requests are submitted
636 	 * until DMA callback for this request is invoked.
637 	 */
638 	req->flags |= SBA_REQUEST_FENCE;
639 
640 	/* Fillup request message */
641 	sba_fillup_interrupt_msg(req, req->cmds, &req->msg);
642 
643 	/* Init async_tx descriptor */
644 	req->tx.flags = flags;
645 	req->tx.cookie = -EBUSY;
646 
647 	return &req->tx;
648 }
649 
650 static void sba_fillup_memcpy_msg(struct sba_request *req,
651 				  struct brcm_sba_command *cmds,
652 				  struct brcm_message *msg,
653 				  dma_addr_t msg_offset, size_t msg_len,
654 				  dma_addr_t dst, dma_addr_t src)
655 {
656 	u64 cmd;
657 	u32 c_mdata;
658 	dma_addr_t resp_dma = req->tx.phys;
659 	struct brcm_sba_command *cmdsp = cmds;
660 
661 	/* Type-B command to load data into buf0 */
662 	cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
663 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
664 	cmd = sba_cmd_enc(cmd, msg_len,
665 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
666 	c_mdata = sba_cmd_load_c_mdata(0);
667 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
668 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
669 	cmd = sba_cmd_enc(cmd, SBA_CMD_LOAD_BUFFER,
670 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
671 	cmdsp->cmd = cmd;
672 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
673 	cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
674 	cmdsp->data = src + msg_offset;
675 	cmdsp->data_len = msg_len;
676 	cmdsp++;
677 
678 	/* Type-A command to write buf0 */
679 	cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
680 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
681 	cmd = sba_cmd_enc(cmd, msg_len,
682 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
683 	cmd = sba_cmd_enc(cmd, 0x1,
684 			  SBA_RESP_SHIFT, SBA_RESP_MASK);
685 	c_mdata = sba_cmd_write_c_mdata(0);
686 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
687 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
688 	cmd = sba_cmd_enc(cmd, SBA_CMD_WRITE_BUFFER,
689 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
690 	cmdsp->cmd = cmd;
691 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
692 	cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
693 	if (req->sba->hw_resp_size) {
694 		cmdsp->flags |= BRCM_SBA_CMD_HAS_RESP;
695 		cmdsp->resp = resp_dma;
696 		cmdsp->resp_len = req->sba->hw_resp_size;
697 	}
698 	cmdsp->flags |= BRCM_SBA_CMD_HAS_OUTPUT;
699 	cmdsp->data = dst + msg_offset;
700 	cmdsp->data_len = msg_len;
701 	cmdsp++;
702 
703 	/* Fillup brcm_message */
704 	msg->type = BRCM_MESSAGE_SBA;
705 	msg->sba.cmds = cmds;
706 	msg->sba.cmds_count = cmdsp - cmds;
707 	msg->ctx = req;
708 	msg->error = 0;
709 }
710 
711 static struct sba_request *
712 sba_prep_dma_memcpy_req(struct sba_device *sba,
713 			dma_addr_t off, dma_addr_t dst, dma_addr_t src,
714 			size_t len, unsigned long flags)
715 {
716 	struct sba_request *req = NULL;
717 
718 	/* Alloc new request */
719 	req = sba_alloc_request(sba);
720 	if (!req)
721 		return NULL;
722 	if (flags & DMA_PREP_FENCE)
723 		req->flags |= SBA_REQUEST_FENCE;
724 
725 	/* Fillup request message */
726 	sba_fillup_memcpy_msg(req, req->cmds, &req->msg,
727 			      off, len, dst, src);
728 
729 	/* Init async_tx descriptor */
730 	req->tx.flags = flags;
731 	req->tx.cookie = -EBUSY;
732 
733 	return req;
734 }
735 
736 static struct dma_async_tx_descriptor *
737 sba_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst, dma_addr_t src,
738 		    size_t len, unsigned long flags)
739 {
740 	size_t req_len;
741 	dma_addr_t off = 0;
742 	struct sba_device *sba = to_sba_device(dchan);
743 	struct sba_request *first = NULL, *req;
744 
745 	/* Create chained requests where each request is upto hw_buf_size */
746 	while (len) {
747 		req_len = (len < sba->hw_buf_size) ? len : sba->hw_buf_size;
748 
749 		req = sba_prep_dma_memcpy_req(sba, off, dst, src,
750 					      req_len, flags);
751 		if (!req) {
752 			if (first)
753 				sba_free_chained_requests(first);
754 			return NULL;
755 		}
756 
757 		if (first)
758 			sba_chain_request(first, req);
759 		else
760 			first = req;
761 
762 		off += req_len;
763 		len -= req_len;
764 	}
765 
766 	return (first) ? &first->tx : NULL;
767 }
768 
769 static void sba_fillup_xor_msg(struct sba_request *req,
770 				struct brcm_sba_command *cmds,
771 				struct brcm_message *msg,
772 				dma_addr_t msg_offset, size_t msg_len,
773 				dma_addr_t dst, dma_addr_t *src, u32 src_cnt)
774 {
775 	u64 cmd;
776 	u32 c_mdata;
777 	unsigned int i;
778 	dma_addr_t resp_dma = req->tx.phys;
779 	struct brcm_sba_command *cmdsp = cmds;
780 
781 	/* Type-B command to load data into buf0 */
782 	cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
783 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
784 	cmd = sba_cmd_enc(cmd, msg_len,
785 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
786 	c_mdata = sba_cmd_load_c_mdata(0);
787 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
788 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
789 	cmd = sba_cmd_enc(cmd, SBA_CMD_LOAD_BUFFER,
790 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
791 	cmdsp->cmd = cmd;
792 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
793 	cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
794 	cmdsp->data = src[0] + msg_offset;
795 	cmdsp->data_len = msg_len;
796 	cmdsp++;
797 
798 	/* Type-B commands to xor data with buf0 and put it back in buf0 */
799 	for (i = 1; i < src_cnt; i++) {
800 		cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
801 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
802 		cmd = sba_cmd_enc(cmd, msg_len,
803 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
804 		c_mdata = sba_cmd_xor_c_mdata(0, 0);
805 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
806 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
807 		cmd = sba_cmd_enc(cmd, SBA_CMD_XOR,
808 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
809 		cmdsp->cmd = cmd;
810 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
811 		cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
812 		cmdsp->data = src[i] + msg_offset;
813 		cmdsp->data_len = msg_len;
814 		cmdsp++;
815 	}
816 
817 	/* Type-A command to write buf0 */
818 	cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
819 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
820 	cmd = sba_cmd_enc(cmd, msg_len,
821 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
822 	cmd = sba_cmd_enc(cmd, 0x1,
823 			  SBA_RESP_SHIFT, SBA_RESP_MASK);
824 	c_mdata = sba_cmd_write_c_mdata(0);
825 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
826 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
827 	cmd = sba_cmd_enc(cmd, SBA_CMD_WRITE_BUFFER,
828 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
829 	cmdsp->cmd = cmd;
830 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
831 	cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
832 	if (req->sba->hw_resp_size) {
833 		cmdsp->flags |= BRCM_SBA_CMD_HAS_RESP;
834 		cmdsp->resp = resp_dma;
835 		cmdsp->resp_len = req->sba->hw_resp_size;
836 	}
837 	cmdsp->flags |= BRCM_SBA_CMD_HAS_OUTPUT;
838 	cmdsp->data = dst + msg_offset;
839 	cmdsp->data_len = msg_len;
840 	cmdsp++;
841 
842 	/* Fillup brcm_message */
843 	msg->type = BRCM_MESSAGE_SBA;
844 	msg->sba.cmds = cmds;
845 	msg->sba.cmds_count = cmdsp - cmds;
846 	msg->ctx = req;
847 	msg->error = 0;
848 }
849 
850 static struct sba_request *
851 sba_prep_dma_xor_req(struct sba_device *sba,
852 		     dma_addr_t off, dma_addr_t dst, dma_addr_t *src,
853 		     u32 src_cnt, size_t len, unsigned long flags)
854 {
855 	struct sba_request *req = NULL;
856 
857 	/* Alloc new request */
858 	req = sba_alloc_request(sba);
859 	if (!req)
860 		return NULL;
861 	if (flags & DMA_PREP_FENCE)
862 		req->flags |= SBA_REQUEST_FENCE;
863 
864 	/* Fillup request message */
865 	sba_fillup_xor_msg(req, req->cmds, &req->msg,
866 			   off, len, dst, src, src_cnt);
867 
868 	/* Init async_tx descriptor */
869 	req->tx.flags = flags;
870 	req->tx.cookie = -EBUSY;
871 
872 	return req;
873 }
874 
875 static struct dma_async_tx_descriptor *
876 sba_prep_dma_xor(struct dma_chan *dchan, dma_addr_t dst, dma_addr_t *src,
877 		 u32 src_cnt, size_t len, unsigned long flags)
878 {
879 	size_t req_len;
880 	dma_addr_t off = 0;
881 	struct sba_device *sba = to_sba_device(dchan);
882 	struct sba_request *first = NULL, *req;
883 
884 	/* Sanity checks */
885 	if (unlikely(src_cnt > sba->max_xor_srcs))
886 		return NULL;
887 
888 	/* Create chained requests where each request is upto hw_buf_size */
889 	while (len) {
890 		req_len = (len < sba->hw_buf_size) ? len : sba->hw_buf_size;
891 
892 		req = sba_prep_dma_xor_req(sba, off, dst, src, src_cnt,
893 					   req_len, flags);
894 		if (!req) {
895 			if (first)
896 				sba_free_chained_requests(first);
897 			return NULL;
898 		}
899 
900 		if (first)
901 			sba_chain_request(first, req);
902 		else
903 			first = req;
904 
905 		off += req_len;
906 		len -= req_len;
907 	}
908 
909 	return (first) ? &first->tx : NULL;
910 }
911 
912 static void sba_fillup_pq_msg(struct sba_request *req,
913 				bool pq_continue,
914 				struct brcm_sba_command *cmds,
915 				struct brcm_message *msg,
916 				dma_addr_t msg_offset, size_t msg_len,
917 				dma_addr_t *dst_p, dma_addr_t *dst_q,
918 				const u8 *scf, dma_addr_t *src, u32 src_cnt)
919 {
920 	u64 cmd;
921 	u32 c_mdata;
922 	unsigned int i;
923 	dma_addr_t resp_dma = req->tx.phys;
924 	struct brcm_sba_command *cmdsp = cmds;
925 
926 	if (pq_continue) {
927 		/* Type-B command to load old P into buf0 */
928 		if (dst_p) {
929 			cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
930 				SBA_TYPE_SHIFT, SBA_TYPE_MASK);
931 			cmd = sba_cmd_enc(cmd, msg_len,
932 				SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
933 			c_mdata = sba_cmd_load_c_mdata(0);
934 			cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
935 				SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
936 			cmd = sba_cmd_enc(cmd, SBA_CMD_LOAD_BUFFER,
937 				SBA_CMD_SHIFT, SBA_CMD_MASK);
938 			cmdsp->cmd = cmd;
939 			*cmdsp->cmd_dma = cpu_to_le64(cmd);
940 			cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
941 			cmdsp->data = *dst_p + msg_offset;
942 			cmdsp->data_len = msg_len;
943 			cmdsp++;
944 		}
945 
946 		/* Type-B command to load old Q into buf1 */
947 		if (dst_q) {
948 			cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
949 				SBA_TYPE_SHIFT, SBA_TYPE_MASK);
950 			cmd = sba_cmd_enc(cmd, msg_len,
951 				SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
952 			c_mdata = sba_cmd_load_c_mdata(1);
953 			cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
954 				SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
955 			cmd = sba_cmd_enc(cmd, SBA_CMD_LOAD_BUFFER,
956 				SBA_CMD_SHIFT, SBA_CMD_MASK);
957 			cmdsp->cmd = cmd;
958 			*cmdsp->cmd_dma = cpu_to_le64(cmd);
959 			cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
960 			cmdsp->data = *dst_q + msg_offset;
961 			cmdsp->data_len = msg_len;
962 			cmdsp++;
963 		}
964 	} else {
965 		/* Type-A command to zero all buffers */
966 		cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
967 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
968 		cmd = sba_cmd_enc(cmd, msg_len,
969 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
970 		cmd = sba_cmd_enc(cmd, SBA_CMD_ZERO_ALL_BUFFERS,
971 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
972 		cmdsp->cmd = cmd;
973 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
974 		cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
975 		cmdsp++;
976 	}
977 
978 	/* Type-B commands for generate P onto buf0 and Q onto buf1 */
979 	for (i = 0; i < src_cnt; i++) {
980 		cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
981 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
982 		cmd = sba_cmd_enc(cmd, msg_len,
983 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
984 		c_mdata = sba_cmd_pq_c_mdata(raid6_gflog[scf[i]], 1, 0);
985 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
986 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
987 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_MS(c_mdata),
988 				  SBA_C_MDATA_MS_SHIFT, SBA_C_MDATA_MS_MASK);
989 		cmd = sba_cmd_enc(cmd, SBA_CMD_GALOIS_XOR,
990 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
991 		cmdsp->cmd = cmd;
992 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
993 		cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
994 		cmdsp->data = src[i] + msg_offset;
995 		cmdsp->data_len = msg_len;
996 		cmdsp++;
997 	}
998 
999 	/* Type-A command to write buf0 */
1000 	if (dst_p) {
1001 		cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
1002 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1003 		cmd = sba_cmd_enc(cmd, msg_len,
1004 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1005 		cmd = sba_cmd_enc(cmd, 0x1,
1006 				  SBA_RESP_SHIFT, SBA_RESP_MASK);
1007 		c_mdata = sba_cmd_write_c_mdata(0);
1008 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1009 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1010 		cmd = sba_cmd_enc(cmd, SBA_CMD_WRITE_BUFFER,
1011 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
1012 		cmdsp->cmd = cmd;
1013 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
1014 		cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
1015 		if (req->sba->hw_resp_size) {
1016 			cmdsp->flags |= BRCM_SBA_CMD_HAS_RESP;
1017 			cmdsp->resp = resp_dma;
1018 			cmdsp->resp_len = req->sba->hw_resp_size;
1019 		}
1020 		cmdsp->flags |= BRCM_SBA_CMD_HAS_OUTPUT;
1021 		cmdsp->data = *dst_p + msg_offset;
1022 		cmdsp->data_len = msg_len;
1023 		cmdsp++;
1024 	}
1025 
1026 	/* Type-A command to write buf1 */
1027 	if (dst_q) {
1028 		cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
1029 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1030 		cmd = sba_cmd_enc(cmd, msg_len,
1031 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1032 		cmd = sba_cmd_enc(cmd, 0x1,
1033 				  SBA_RESP_SHIFT, SBA_RESP_MASK);
1034 		c_mdata = sba_cmd_write_c_mdata(1);
1035 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1036 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1037 		cmd = sba_cmd_enc(cmd, SBA_CMD_WRITE_BUFFER,
1038 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
1039 		cmdsp->cmd = cmd;
1040 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
1041 		cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
1042 		if (req->sba->hw_resp_size) {
1043 			cmdsp->flags |= BRCM_SBA_CMD_HAS_RESP;
1044 			cmdsp->resp = resp_dma;
1045 			cmdsp->resp_len = req->sba->hw_resp_size;
1046 		}
1047 		cmdsp->flags |= BRCM_SBA_CMD_HAS_OUTPUT;
1048 		cmdsp->data = *dst_q + msg_offset;
1049 		cmdsp->data_len = msg_len;
1050 		cmdsp++;
1051 	}
1052 
1053 	/* Fillup brcm_message */
1054 	msg->type = BRCM_MESSAGE_SBA;
1055 	msg->sba.cmds = cmds;
1056 	msg->sba.cmds_count = cmdsp - cmds;
1057 	msg->ctx = req;
1058 	msg->error = 0;
1059 }
1060 
1061 static struct sba_request *
1062 sba_prep_dma_pq_req(struct sba_device *sba, dma_addr_t off,
1063 		    dma_addr_t *dst_p, dma_addr_t *dst_q, dma_addr_t *src,
1064 		    u32 src_cnt, const u8 *scf, size_t len, unsigned long flags)
1065 {
1066 	struct sba_request *req = NULL;
1067 
1068 	/* Alloc new request */
1069 	req = sba_alloc_request(sba);
1070 	if (!req)
1071 		return NULL;
1072 	if (flags & DMA_PREP_FENCE)
1073 		req->flags |= SBA_REQUEST_FENCE;
1074 
1075 	/* Fillup request messages */
1076 	sba_fillup_pq_msg(req, dmaf_continue(flags),
1077 			  req->cmds, &req->msg,
1078 			  off, len, dst_p, dst_q, scf, src, src_cnt);
1079 
1080 	/* Init async_tx descriptor */
1081 	req->tx.flags = flags;
1082 	req->tx.cookie = -EBUSY;
1083 
1084 	return req;
1085 }
1086 
1087 static void sba_fillup_pq_single_msg(struct sba_request *req,
1088 				bool pq_continue,
1089 				struct brcm_sba_command *cmds,
1090 				struct brcm_message *msg,
1091 				dma_addr_t msg_offset, size_t msg_len,
1092 				dma_addr_t *dst_p, dma_addr_t *dst_q,
1093 				dma_addr_t src, u8 scf)
1094 {
1095 	u64 cmd;
1096 	u32 c_mdata;
1097 	u8 pos, dpos = raid6_gflog[scf];
1098 	dma_addr_t resp_dma = req->tx.phys;
1099 	struct brcm_sba_command *cmdsp = cmds;
1100 
1101 	if (!dst_p)
1102 		goto skip_p;
1103 
1104 	if (pq_continue) {
1105 		/* Type-B command to load old P into buf0 */
1106 		cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
1107 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1108 		cmd = sba_cmd_enc(cmd, msg_len,
1109 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1110 		c_mdata = sba_cmd_load_c_mdata(0);
1111 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1112 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1113 		cmd = sba_cmd_enc(cmd, SBA_CMD_LOAD_BUFFER,
1114 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
1115 		cmdsp->cmd = cmd;
1116 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
1117 		cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
1118 		cmdsp->data = *dst_p + msg_offset;
1119 		cmdsp->data_len = msg_len;
1120 		cmdsp++;
1121 
1122 		/*
1123 		 * Type-B commands to xor data with buf0 and put it
1124 		 * back in buf0
1125 		 */
1126 		cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
1127 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1128 		cmd = sba_cmd_enc(cmd, msg_len,
1129 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1130 		c_mdata = sba_cmd_xor_c_mdata(0, 0);
1131 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1132 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1133 		cmd = sba_cmd_enc(cmd, SBA_CMD_XOR,
1134 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
1135 		cmdsp->cmd = cmd;
1136 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
1137 		cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
1138 		cmdsp->data = src + msg_offset;
1139 		cmdsp->data_len = msg_len;
1140 		cmdsp++;
1141 	} else {
1142 		/* Type-B command to load old P into buf0 */
1143 		cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
1144 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1145 		cmd = sba_cmd_enc(cmd, msg_len,
1146 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1147 		c_mdata = sba_cmd_load_c_mdata(0);
1148 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1149 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1150 		cmd = sba_cmd_enc(cmd, SBA_CMD_LOAD_BUFFER,
1151 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
1152 		cmdsp->cmd = cmd;
1153 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
1154 		cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
1155 		cmdsp->data = src + msg_offset;
1156 		cmdsp->data_len = msg_len;
1157 		cmdsp++;
1158 	}
1159 
1160 	/* Type-A command to write buf0 */
1161 	cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
1162 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1163 	cmd = sba_cmd_enc(cmd, msg_len,
1164 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1165 	cmd = sba_cmd_enc(cmd, 0x1,
1166 			  SBA_RESP_SHIFT, SBA_RESP_MASK);
1167 	c_mdata = sba_cmd_write_c_mdata(0);
1168 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1169 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1170 	cmd = sba_cmd_enc(cmd, SBA_CMD_WRITE_BUFFER,
1171 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
1172 	cmdsp->cmd = cmd;
1173 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
1174 	cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
1175 	if (req->sba->hw_resp_size) {
1176 		cmdsp->flags |= BRCM_SBA_CMD_HAS_RESP;
1177 		cmdsp->resp = resp_dma;
1178 		cmdsp->resp_len = req->sba->hw_resp_size;
1179 	}
1180 	cmdsp->flags |= BRCM_SBA_CMD_HAS_OUTPUT;
1181 	cmdsp->data = *dst_p + msg_offset;
1182 	cmdsp->data_len = msg_len;
1183 	cmdsp++;
1184 
1185 skip_p:
1186 	if (!dst_q)
1187 		goto skip_q;
1188 
1189 	/* Type-A command to zero all buffers */
1190 	cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
1191 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1192 	cmd = sba_cmd_enc(cmd, msg_len,
1193 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1194 	cmd = sba_cmd_enc(cmd, SBA_CMD_ZERO_ALL_BUFFERS,
1195 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
1196 	cmdsp->cmd = cmd;
1197 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
1198 	cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
1199 	cmdsp++;
1200 
1201 	if (dpos == 255)
1202 		goto skip_q_computation;
1203 	pos = (dpos < req->sba->max_pq_coefs) ?
1204 		dpos : (req->sba->max_pq_coefs - 1);
1205 
1206 	/*
1207 	 * Type-B command to generate initial Q from data
1208 	 * and store output into buf0
1209 	 */
1210 	cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
1211 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1212 	cmd = sba_cmd_enc(cmd, msg_len,
1213 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1214 	c_mdata = sba_cmd_pq_c_mdata(pos, 0, 0);
1215 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1216 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1217 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_MS(c_mdata),
1218 			  SBA_C_MDATA_MS_SHIFT, SBA_C_MDATA_MS_MASK);
1219 	cmd = sba_cmd_enc(cmd, SBA_CMD_GALOIS,
1220 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
1221 	cmdsp->cmd = cmd;
1222 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
1223 	cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
1224 	cmdsp->data = src + msg_offset;
1225 	cmdsp->data_len = msg_len;
1226 	cmdsp++;
1227 
1228 	dpos -= pos;
1229 
1230 	/* Multiple Type-A command to generate final Q */
1231 	while (dpos) {
1232 		pos = (dpos < req->sba->max_pq_coefs) ?
1233 			dpos : (req->sba->max_pq_coefs - 1);
1234 
1235 		/*
1236 		 * Type-A command to generate Q with buf0 and
1237 		 * buf1 store result in buf0
1238 		 */
1239 		cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
1240 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1241 		cmd = sba_cmd_enc(cmd, msg_len,
1242 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1243 		c_mdata = sba_cmd_pq_c_mdata(pos, 0, 1);
1244 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1245 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1246 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_MS(c_mdata),
1247 				  SBA_C_MDATA_MS_SHIFT, SBA_C_MDATA_MS_MASK);
1248 		cmd = sba_cmd_enc(cmd, SBA_CMD_GALOIS,
1249 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
1250 		cmdsp->cmd = cmd;
1251 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
1252 		cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
1253 		cmdsp++;
1254 
1255 		dpos -= pos;
1256 	}
1257 
1258 skip_q_computation:
1259 	if (pq_continue) {
1260 		/*
1261 		 * Type-B command to XOR previous output with
1262 		 * buf0 and write it into buf0
1263 		 */
1264 		cmd = sba_cmd_enc(0x0, SBA_TYPE_B,
1265 				  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1266 		cmd = sba_cmd_enc(cmd, msg_len,
1267 				  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1268 		c_mdata = sba_cmd_xor_c_mdata(0, 0);
1269 		cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1270 				  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1271 		cmd = sba_cmd_enc(cmd, SBA_CMD_XOR,
1272 				  SBA_CMD_SHIFT, SBA_CMD_MASK);
1273 		cmdsp->cmd = cmd;
1274 		*cmdsp->cmd_dma = cpu_to_le64(cmd);
1275 		cmdsp->flags = BRCM_SBA_CMD_TYPE_B;
1276 		cmdsp->data = *dst_q + msg_offset;
1277 		cmdsp->data_len = msg_len;
1278 		cmdsp++;
1279 	}
1280 
1281 	/* Type-A command to write buf0 */
1282 	cmd = sba_cmd_enc(0x0, SBA_TYPE_A,
1283 			  SBA_TYPE_SHIFT, SBA_TYPE_MASK);
1284 	cmd = sba_cmd_enc(cmd, msg_len,
1285 			  SBA_USER_DEF_SHIFT, SBA_USER_DEF_MASK);
1286 	cmd = sba_cmd_enc(cmd, 0x1,
1287 			  SBA_RESP_SHIFT, SBA_RESP_MASK);
1288 	c_mdata = sba_cmd_write_c_mdata(0);
1289 	cmd = sba_cmd_enc(cmd, SBA_C_MDATA_LS(c_mdata),
1290 			  SBA_C_MDATA_SHIFT, SBA_C_MDATA_MASK);
1291 	cmd = sba_cmd_enc(cmd, SBA_CMD_WRITE_BUFFER,
1292 			  SBA_CMD_SHIFT, SBA_CMD_MASK);
1293 	cmdsp->cmd = cmd;
1294 	*cmdsp->cmd_dma = cpu_to_le64(cmd);
1295 	cmdsp->flags = BRCM_SBA_CMD_TYPE_A;
1296 	if (req->sba->hw_resp_size) {
1297 		cmdsp->flags |= BRCM_SBA_CMD_HAS_RESP;
1298 		cmdsp->resp = resp_dma;
1299 		cmdsp->resp_len = req->sba->hw_resp_size;
1300 	}
1301 	cmdsp->flags |= BRCM_SBA_CMD_HAS_OUTPUT;
1302 	cmdsp->data = *dst_q + msg_offset;
1303 	cmdsp->data_len = msg_len;
1304 	cmdsp++;
1305 
1306 skip_q:
1307 	/* Fillup brcm_message */
1308 	msg->type = BRCM_MESSAGE_SBA;
1309 	msg->sba.cmds = cmds;
1310 	msg->sba.cmds_count = cmdsp - cmds;
1311 	msg->ctx = req;
1312 	msg->error = 0;
1313 }
1314 
1315 static struct sba_request *
1316 sba_prep_dma_pq_single_req(struct sba_device *sba, dma_addr_t off,
1317 			   dma_addr_t *dst_p, dma_addr_t *dst_q,
1318 			   dma_addr_t src, u8 scf, size_t len,
1319 			   unsigned long flags)
1320 {
1321 	struct sba_request *req = NULL;
1322 
1323 	/* Alloc new request */
1324 	req = sba_alloc_request(sba);
1325 	if (!req)
1326 		return NULL;
1327 	if (flags & DMA_PREP_FENCE)
1328 		req->flags |= SBA_REQUEST_FENCE;
1329 
1330 	/* Fillup request messages */
1331 	sba_fillup_pq_single_msg(req,  dmaf_continue(flags),
1332 				 req->cmds, &req->msg, off, len,
1333 				 dst_p, dst_q, src, scf);
1334 
1335 	/* Init async_tx descriptor */
1336 	req->tx.flags = flags;
1337 	req->tx.cookie = -EBUSY;
1338 
1339 	return req;
1340 }
1341 
1342 static struct dma_async_tx_descriptor *
1343 sba_prep_dma_pq(struct dma_chan *dchan, dma_addr_t *dst, dma_addr_t *src,
1344 		u32 src_cnt, const u8 *scf, size_t len, unsigned long flags)
1345 {
1346 	u32 i, dst_q_index;
1347 	size_t req_len;
1348 	bool slow = false;
1349 	dma_addr_t off = 0;
1350 	dma_addr_t *dst_p = NULL, *dst_q = NULL;
1351 	struct sba_device *sba = to_sba_device(dchan);
1352 	struct sba_request *first = NULL, *req;
1353 
1354 	/* Sanity checks */
1355 	if (unlikely(src_cnt > sba->max_pq_srcs))
1356 		return NULL;
1357 	for (i = 0; i < src_cnt; i++)
1358 		if (sba->max_pq_coefs <= raid6_gflog[scf[i]])
1359 			slow = true;
1360 
1361 	/* Figure-out P and Q destination addresses */
1362 	if (!(flags & DMA_PREP_PQ_DISABLE_P))
1363 		dst_p = &dst[0];
1364 	if (!(flags & DMA_PREP_PQ_DISABLE_Q))
1365 		dst_q = &dst[1];
1366 
1367 	/* Create chained requests where each request is upto hw_buf_size */
1368 	while (len) {
1369 		req_len = (len < sba->hw_buf_size) ? len : sba->hw_buf_size;
1370 
1371 		if (slow) {
1372 			dst_q_index = src_cnt;
1373 
1374 			if (dst_q) {
1375 				for (i = 0; i < src_cnt; i++) {
1376 					if (*dst_q == src[i]) {
1377 						dst_q_index = i;
1378 						break;
1379 					}
1380 				}
1381 			}
1382 
1383 			if (dst_q_index < src_cnt) {
1384 				i = dst_q_index;
1385 				req = sba_prep_dma_pq_single_req(sba,
1386 					off, dst_p, dst_q, src[i], scf[i],
1387 					req_len, flags | DMA_PREP_FENCE);
1388 				if (!req)
1389 					goto fail;
1390 
1391 				if (first)
1392 					sba_chain_request(first, req);
1393 				else
1394 					first = req;
1395 
1396 				flags |= DMA_PREP_CONTINUE;
1397 			}
1398 
1399 			for (i = 0; i < src_cnt; i++) {
1400 				if (dst_q_index == i)
1401 					continue;
1402 
1403 				req = sba_prep_dma_pq_single_req(sba,
1404 					off, dst_p, dst_q, src[i], scf[i],
1405 					req_len, flags | DMA_PREP_FENCE);
1406 				if (!req)
1407 					goto fail;
1408 
1409 				if (first)
1410 					sba_chain_request(first, req);
1411 				else
1412 					first = req;
1413 
1414 				flags |= DMA_PREP_CONTINUE;
1415 			}
1416 		} else {
1417 			req = sba_prep_dma_pq_req(sba, off,
1418 						  dst_p, dst_q, src, src_cnt,
1419 						  scf, req_len, flags);
1420 			if (!req)
1421 				goto fail;
1422 
1423 			if (first)
1424 				sba_chain_request(first, req);
1425 			else
1426 				first = req;
1427 		}
1428 
1429 		off += req_len;
1430 		len -= req_len;
1431 	}
1432 
1433 	return (first) ? &first->tx : NULL;
1434 
1435 fail:
1436 	if (first)
1437 		sba_free_chained_requests(first);
1438 	return NULL;
1439 }
1440 
1441 /* ====== Mailbox callbacks ===== */
1442 
1443 static void sba_receive_message(struct mbox_client *cl, void *msg)
1444 {
1445 	struct brcm_message *m = msg;
1446 	struct sba_request *req = m->ctx;
1447 	struct sba_device *sba = req->sba;
1448 
1449 	/* Error count if message has error */
1450 	if (m->error < 0)
1451 		dev_err(sba->dev, "%s got message with error %d",
1452 			dma_chan_name(&sba->dma_chan), m->error);
1453 
1454 	/* Process received request */
1455 	sba_process_received_request(sba, req);
1456 }
1457 
1458 /* ====== Debugfs callbacks ====== */
1459 
1460 static int sba_debugfs_stats_show(struct seq_file *file, void *offset)
1461 {
1462 	struct platform_device *pdev = to_platform_device(file->private);
1463 	struct sba_device *sba = platform_get_drvdata(pdev);
1464 
1465 	/* Write stats in file */
1466 	sba_write_stats_in_seqfile(sba, file);
1467 
1468 	return 0;
1469 }
1470 
1471 /* ====== Platform driver routines ===== */
1472 
1473 static int sba_prealloc_channel_resources(struct sba_device *sba)
1474 {
1475 	int i, j, ret = 0;
1476 	struct sba_request *req = NULL;
1477 
1478 	sba->resp_base = dma_alloc_coherent(sba->mbox_dev,
1479 					    sba->max_resp_pool_size,
1480 					    &sba->resp_dma_base, GFP_KERNEL);
1481 	if (!sba->resp_base)
1482 		return -ENOMEM;
1483 
1484 	sba->cmds_base = dma_alloc_coherent(sba->mbox_dev,
1485 					    sba->max_cmds_pool_size,
1486 					    &sba->cmds_dma_base, GFP_KERNEL);
1487 	if (!sba->cmds_base) {
1488 		ret = -ENOMEM;
1489 		goto fail_free_resp_pool;
1490 	}
1491 
1492 	spin_lock_init(&sba->reqs_lock);
1493 	sba->reqs_fence = false;
1494 	INIT_LIST_HEAD(&sba->reqs_alloc_list);
1495 	INIT_LIST_HEAD(&sba->reqs_pending_list);
1496 	INIT_LIST_HEAD(&sba->reqs_active_list);
1497 	INIT_LIST_HEAD(&sba->reqs_aborted_list);
1498 	INIT_LIST_HEAD(&sba->reqs_free_list);
1499 
1500 	for (i = 0; i < sba->max_req; i++) {
1501 		req = devm_kzalloc(sba->dev,
1502 				sizeof(*req) +
1503 				sba->max_cmd_per_req * sizeof(req->cmds[0]),
1504 				GFP_KERNEL);
1505 		if (!req) {
1506 			ret = -ENOMEM;
1507 			goto fail_free_cmds_pool;
1508 		}
1509 		INIT_LIST_HEAD(&req->node);
1510 		req->sba = sba;
1511 		req->flags = SBA_REQUEST_STATE_FREE;
1512 		INIT_LIST_HEAD(&req->next);
1513 		atomic_set(&req->next_pending_count, 0);
1514 		for (j = 0; j < sba->max_cmd_per_req; j++) {
1515 			req->cmds[j].cmd = 0;
1516 			req->cmds[j].cmd_dma = sba->cmds_base +
1517 				(i * sba->max_cmd_per_req + j) * sizeof(u64);
1518 			req->cmds[j].cmd_dma_addr = sba->cmds_dma_base +
1519 				(i * sba->max_cmd_per_req + j) * sizeof(u64);
1520 			req->cmds[j].flags = 0;
1521 		}
1522 		memset(&req->msg, 0, sizeof(req->msg));
1523 		dma_async_tx_descriptor_init(&req->tx, &sba->dma_chan);
1524 		async_tx_ack(&req->tx);
1525 		req->tx.tx_submit = sba_tx_submit;
1526 		req->tx.phys = sba->resp_dma_base + i * sba->hw_resp_size;
1527 		list_add_tail(&req->node, &sba->reqs_free_list);
1528 	}
1529 
1530 	return 0;
1531 
1532 fail_free_cmds_pool:
1533 	dma_free_coherent(sba->mbox_dev,
1534 			  sba->max_cmds_pool_size,
1535 			  sba->cmds_base, sba->cmds_dma_base);
1536 fail_free_resp_pool:
1537 	dma_free_coherent(sba->mbox_dev,
1538 			  sba->max_resp_pool_size,
1539 			  sba->resp_base, sba->resp_dma_base);
1540 	return ret;
1541 }
1542 
1543 static void sba_freeup_channel_resources(struct sba_device *sba)
1544 {
1545 	dmaengine_terminate_all(&sba->dma_chan);
1546 	dma_free_coherent(sba->mbox_dev, sba->max_cmds_pool_size,
1547 			  sba->cmds_base, sba->cmds_dma_base);
1548 	dma_free_coherent(sba->mbox_dev, sba->max_resp_pool_size,
1549 			  sba->resp_base, sba->resp_dma_base);
1550 	sba->resp_base = NULL;
1551 	sba->resp_dma_base = 0;
1552 }
1553 
1554 static int sba_async_register(struct sba_device *sba)
1555 {
1556 	int ret;
1557 	struct dma_device *dma_dev = &sba->dma_dev;
1558 
1559 	/* Initialize DMA channel cookie */
1560 	sba->dma_chan.device = dma_dev;
1561 	dma_cookie_init(&sba->dma_chan);
1562 
1563 	/* Initialize DMA device capability mask */
1564 	dma_cap_zero(dma_dev->cap_mask);
1565 	dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask);
1566 	dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
1567 	dma_cap_set(DMA_XOR, dma_dev->cap_mask);
1568 	dma_cap_set(DMA_PQ, dma_dev->cap_mask);
1569 
1570 	/*
1571 	 * Set mailbox channel device as the base device of
1572 	 * our dma_device because the actual memory accesses
1573 	 * will be done by mailbox controller
1574 	 */
1575 	dma_dev->dev = sba->mbox_dev;
1576 
1577 	/* Set base prep routines */
1578 	dma_dev->device_free_chan_resources = sba_free_chan_resources;
1579 	dma_dev->device_terminate_all = sba_device_terminate_all;
1580 	dma_dev->device_issue_pending = sba_issue_pending;
1581 	dma_dev->device_tx_status = sba_tx_status;
1582 
1583 	/* Set interrupt routine */
1584 	if (dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask))
1585 		dma_dev->device_prep_dma_interrupt = sba_prep_dma_interrupt;
1586 
1587 	/* Set memcpy routine */
1588 	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask))
1589 		dma_dev->device_prep_dma_memcpy = sba_prep_dma_memcpy;
1590 
1591 	/* Set xor routine and capability */
1592 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1593 		dma_dev->device_prep_dma_xor = sba_prep_dma_xor;
1594 		dma_dev->max_xor = sba->max_xor_srcs;
1595 	}
1596 
1597 	/* Set pq routine and capability */
1598 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
1599 		dma_dev->device_prep_dma_pq = sba_prep_dma_pq;
1600 		dma_set_maxpq(dma_dev, sba->max_pq_srcs, 0);
1601 	}
1602 
1603 	/* Initialize DMA device channel list */
1604 	INIT_LIST_HEAD(&dma_dev->channels);
1605 	list_add_tail(&sba->dma_chan.device_node, &dma_dev->channels);
1606 
1607 	/* Register with Linux async DMA framework*/
1608 	ret = dma_async_device_register(dma_dev);
1609 	if (ret) {
1610 		dev_err(sba->dev, "async device register error %d", ret);
1611 		return ret;
1612 	}
1613 
1614 	dev_info(sba->dev, "%s capabilities: %s%s%s%s\n",
1615 	dma_chan_name(&sba->dma_chan),
1616 	dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask) ? "interrupt " : "",
1617 	dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "memcpy " : "",
1618 	dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "",
1619 	dma_has_cap(DMA_PQ, dma_dev->cap_mask) ? "pq " : "");
1620 
1621 	return 0;
1622 }
1623 
1624 static int sba_probe(struct platform_device *pdev)
1625 {
1626 	int ret = 0;
1627 	struct sba_device *sba;
1628 	struct platform_device *mbox_pdev;
1629 	struct of_phandle_args args;
1630 
1631 	/* Allocate main SBA struct */
1632 	sba = devm_kzalloc(&pdev->dev, sizeof(*sba), GFP_KERNEL);
1633 	if (!sba)
1634 		return -ENOMEM;
1635 
1636 	sba->dev = &pdev->dev;
1637 	platform_set_drvdata(pdev, sba);
1638 
1639 	/* Number of mailbox channels should be atleast 1 */
1640 	ret = of_count_phandle_with_args(pdev->dev.of_node,
1641 					 "mboxes", "#mbox-cells");
1642 	if (ret <= 0)
1643 		return -ENODEV;
1644 
1645 	/* Determine SBA version from DT compatible string */
1646 	if (of_device_is_compatible(sba->dev->of_node, "brcm,iproc-sba"))
1647 		sba->ver = SBA_VER_1;
1648 	else if (of_device_is_compatible(sba->dev->of_node,
1649 					 "brcm,iproc-sba-v2"))
1650 		sba->ver = SBA_VER_2;
1651 	else
1652 		return -ENODEV;
1653 
1654 	/* Derived Configuration parameters */
1655 	switch (sba->ver) {
1656 	case SBA_VER_1:
1657 		sba->hw_buf_size = 4096;
1658 		sba->hw_resp_size = 8;
1659 		sba->max_pq_coefs = 6;
1660 		sba->max_pq_srcs = 6;
1661 		break;
1662 	case SBA_VER_2:
1663 		sba->hw_buf_size = 4096;
1664 		sba->hw_resp_size = 8;
1665 		sba->max_pq_coefs = 30;
1666 		/*
1667 		 * We can support max_pq_srcs == max_pq_coefs because
1668 		 * we are limited by number of SBA commands that we can
1669 		 * fit in one message for underlying ring manager HW.
1670 		 */
1671 		sba->max_pq_srcs = 12;
1672 		break;
1673 	default:
1674 		return -EINVAL;
1675 	}
1676 	sba->max_req = SBA_MAX_REQ_PER_MBOX_CHANNEL;
1677 	sba->max_cmd_per_req = sba->max_pq_srcs + 3;
1678 	sba->max_xor_srcs = sba->max_cmd_per_req - 1;
1679 	sba->max_resp_pool_size = sba->max_req * sba->hw_resp_size;
1680 	sba->max_cmds_pool_size = sba->max_req *
1681 				  sba->max_cmd_per_req * sizeof(u64);
1682 
1683 	/* Setup mailbox client */
1684 	sba->client.dev			= &pdev->dev;
1685 	sba->client.rx_callback		= sba_receive_message;
1686 	sba->client.tx_block		= false;
1687 	sba->client.knows_txdone	= true;
1688 	sba->client.tx_tout		= 0;
1689 
1690 	/* Request mailbox channel */
1691 	sba->mchan = mbox_request_channel(&sba->client, 0);
1692 	if (IS_ERR(sba->mchan)) {
1693 		ret = PTR_ERR(sba->mchan);
1694 		goto fail_free_mchan;
1695 	}
1696 
1697 	/* Find-out underlying mailbox device */
1698 	ret = of_parse_phandle_with_args(pdev->dev.of_node,
1699 					 "mboxes", "#mbox-cells", 0, &args);
1700 	if (ret)
1701 		goto fail_free_mchan;
1702 	mbox_pdev = of_find_device_by_node(args.np);
1703 	of_node_put(args.np);
1704 	if (!mbox_pdev) {
1705 		ret = -ENODEV;
1706 		goto fail_free_mchan;
1707 	}
1708 	sba->mbox_dev = &mbox_pdev->dev;
1709 
1710 	/* Prealloc channel resource */
1711 	ret = sba_prealloc_channel_resources(sba);
1712 	if (ret)
1713 		goto fail_free_mchan;
1714 
1715 	/* Check availability of debugfs */
1716 	if (!debugfs_initialized())
1717 		goto skip_debugfs;
1718 
1719 	/* Create debugfs root entry */
1720 	sba->root = debugfs_create_dir(dev_name(sba->dev), NULL);
1721 	if (IS_ERR_OR_NULL(sba->root)) {
1722 		dev_err(sba->dev, "failed to create debugfs root entry\n");
1723 		sba->root = NULL;
1724 		goto skip_debugfs;
1725 	}
1726 
1727 	/* Create debugfs stats entry */
1728 	sba->stats = debugfs_create_devm_seqfile(sba->dev, "stats", sba->root,
1729 						 sba_debugfs_stats_show);
1730 	if (IS_ERR_OR_NULL(sba->stats))
1731 		dev_err(sba->dev, "failed to create debugfs stats file\n");
1732 skip_debugfs:
1733 
1734 	/* Register DMA device with Linux async framework */
1735 	ret = sba_async_register(sba);
1736 	if (ret)
1737 		goto fail_free_resources;
1738 
1739 	/* Print device info */
1740 	dev_info(sba->dev, "%s using SBAv%d mailbox channel from %s",
1741 		 dma_chan_name(&sba->dma_chan), sba->ver+1,
1742 		 dev_name(sba->mbox_dev));
1743 
1744 	return 0;
1745 
1746 fail_free_resources:
1747 	debugfs_remove_recursive(sba->root);
1748 	sba_freeup_channel_resources(sba);
1749 fail_free_mchan:
1750 	mbox_free_channel(sba->mchan);
1751 	return ret;
1752 }
1753 
1754 static int sba_remove(struct platform_device *pdev)
1755 {
1756 	struct sba_device *sba = platform_get_drvdata(pdev);
1757 
1758 	dma_async_device_unregister(&sba->dma_dev);
1759 
1760 	debugfs_remove_recursive(sba->root);
1761 
1762 	sba_freeup_channel_resources(sba);
1763 
1764 	mbox_free_channel(sba->mchan);
1765 
1766 	return 0;
1767 }
1768 
1769 static const struct of_device_id sba_of_match[] = {
1770 	{ .compatible = "brcm,iproc-sba", },
1771 	{ .compatible = "brcm,iproc-sba-v2", },
1772 	{},
1773 };
1774 MODULE_DEVICE_TABLE(of, sba_of_match);
1775 
1776 static struct platform_driver sba_driver = {
1777 	.probe = sba_probe,
1778 	.remove = sba_remove,
1779 	.driver = {
1780 		.name = "bcm-sba-raid",
1781 		.of_match_table = sba_of_match,
1782 	},
1783 };
1784 module_platform_driver(sba_driver);
1785 
1786 MODULE_DESCRIPTION("Broadcom SBA RAID driver");
1787 MODULE_AUTHOR("Anup Patel <anup.patel@broadcom.com>");
1788 MODULE_LICENSE("GPL v2");
1789