xref: /openbmc/linux/drivers/crypto/mxs-dcp.c (revision 35267cea)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Freescale i.MX23/i.MX28 Data Co-Processor driver
4  *
5  * Copyright (C) 2013 Marek Vasut <marex@denx.de>
6  */
7 
8 #include <linux/dma-mapping.h>
9 #include <linux/interrupt.h>
10 #include <linux/io.h>
11 #include <linux/kernel.h>
12 #include <linux/kthread.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/stmp_device.h>
17 #include <linux/clk.h>
18 
19 #include <crypto/aes.h>
20 #include <crypto/sha1.h>
21 #include <crypto/sha2.h>
22 #include <crypto/internal/hash.h>
23 #include <crypto/internal/skcipher.h>
24 #include <crypto/scatterwalk.h>
25 
26 #define DCP_MAX_CHANS	4
27 #define DCP_BUF_SZ	PAGE_SIZE
28 #define DCP_SHA_PAY_SZ  64
29 
30 #define DCP_ALIGNMENT	64
31 
32 /*
33  * Null hashes to align with hw behavior on imx6sl and ull
34  * these are flipped for consistency with hw output
35  */
36 static const uint8_t sha1_null_hash[] =
37 	"\x09\x07\xd8\xaf\x90\x18\x60\x95\xef\xbf"
38 	"\x55\x32\x0d\x4b\x6b\x5e\xee\xa3\x39\xda";
39 
40 static const uint8_t sha256_null_hash[] =
41 	"\x55\xb8\x52\x78\x1b\x99\x95\xa4"
42 	"\x4c\x93\x9b\x64\xe4\x41\xae\x27"
43 	"\x24\xb9\x6f\x99\xc8\xf4\xfb\x9a"
44 	"\x14\x1c\xfc\x98\x42\xc4\xb0\xe3";
45 
46 /* DCP DMA descriptor. */
47 struct dcp_dma_desc {
48 	uint32_t	next_cmd_addr;
49 	uint32_t	control0;
50 	uint32_t	control1;
51 	uint32_t	source;
52 	uint32_t	destination;
53 	uint32_t	size;
54 	uint32_t	payload;
55 	uint32_t	status;
56 };
57 
58 /* Coherent aligned block for bounce buffering. */
59 struct dcp_coherent_block {
60 	uint8_t			aes_in_buf[DCP_BUF_SZ];
61 	uint8_t			aes_out_buf[DCP_BUF_SZ];
62 	uint8_t			sha_in_buf[DCP_BUF_SZ];
63 	uint8_t			sha_out_buf[DCP_SHA_PAY_SZ];
64 
65 	uint8_t			aes_key[2 * AES_KEYSIZE_128];
66 
67 	struct dcp_dma_desc	desc[DCP_MAX_CHANS];
68 };
69 
70 struct dcp {
71 	struct device			*dev;
72 	void __iomem			*base;
73 
74 	uint32_t			caps;
75 
76 	struct dcp_coherent_block	*coh;
77 
78 	struct completion		completion[DCP_MAX_CHANS];
79 	spinlock_t			lock[DCP_MAX_CHANS];
80 	struct task_struct		*thread[DCP_MAX_CHANS];
81 	struct crypto_queue		queue[DCP_MAX_CHANS];
82 	struct clk			*dcp_clk;
83 };
84 
85 enum dcp_chan {
86 	DCP_CHAN_HASH_SHA	= 0,
87 	DCP_CHAN_CRYPTO		= 2,
88 };
89 
90 struct dcp_async_ctx {
91 	/* Common context */
92 	enum dcp_chan	chan;
93 	uint32_t	fill;
94 
95 	/* SHA Hash-specific context */
96 	struct mutex			mutex;
97 	uint32_t			alg;
98 	unsigned int			hot:1;
99 
100 	/* Crypto-specific context */
101 	struct crypto_skcipher		*fallback;
102 	unsigned int			key_len;
103 	uint8_t				key[AES_KEYSIZE_128];
104 };
105 
106 struct dcp_aes_req_ctx {
107 	unsigned int	enc:1;
108 	unsigned int	ecb:1;
109 	struct skcipher_request fallback_req;	// keep at the end
110 };
111 
112 struct dcp_sha_req_ctx {
113 	unsigned int	init:1;
114 	unsigned int	fini:1;
115 };
116 
117 struct dcp_export_state {
118 	struct dcp_sha_req_ctx req_ctx;
119 	struct dcp_async_ctx async_ctx;
120 };
121 
122 /*
123  * There can even be only one instance of the MXS DCP due to the
124  * design of Linux Crypto API.
125  */
126 static struct dcp *global_sdcp;
127 
128 /* DCP register layout. */
129 #define MXS_DCP_CTRL				0x00
130 #define MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES	(1 << 23)
131 #define MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING	(1 << 22)
132 
133 #define MXS_DCP_STAT				0x10
134 #define MXS_DCP_STAT_CLR			0x18
135 #define MXS_DCP_STAT_IRQ_MASK			0xf
136 
137 #define MXS_DCP_CHANNELCTRL			0x20
138 #define MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK	0xff
139 
140 #define MXS_DCP_CAPABILITY1			0x40
141 #define MXS_DCP_CAPABILITY1_SHA256		(4 << 16)
142 #define MXS_DCP_CAPABILITY1_SHA1		(1 << 16)
143 #define MXS_DCP_CAPABILITY1_AES128		(1 << 0)
144 
145 #define MXS_DCP_CONTEXT				0x50
146 
147 #define MXS_DCP_CH_N_CMDPTR(n)			(0x100 + ((n) * 0x40))
148 
149 #define MXS_DCP_CH_N_SEMA(n)			(0x110 + ((n) * 0x40))
150 
151 #define MXS_DCP_CH_N_STAT(n)			(0x120 + ((n) * 0x40))
152 #define MXS_DCP_CH_N_STAT_CLR(n)		(0x128 + ((n) * 0x40))
153 
154 /* DMA descriptor bits. */
155 #define MXS_DCP_CONTROL0_HASH_TERM		(1 << 13)
156 #define MXS_DCP_CONTROL0_HASH_INIT		(1 << 12)
157 #define MXS_DCP_CONTROL0_PAYLOAD_KEY		(1 << 11)
158 #define MXS_DCP_CONTROL0_CIPHER_ENCRYPT		(1 << 8)
159 #define MXS_DCP_CONTROL0_CIPHER_INIT		(1 << 9)
160 #define MXS_DCP_CONTROL0_ENABLE_HASH		(1 << 6)
161 #define MXS_DCP_CONTROL0_ENABLE_CIPHER		(1 << 5)
162 #define MXS_DCP_CONTROL0_DECR_SEMAPHORE		(1 << 1)
163 #define MXS_DCP_CONTROL0_INTERRUPT		(1 << 0)
164 
165 #define MXS_DCP_CONTROL1_HASH_SELECT_SHA256	(2 << 16)
166 #define MXS_DCP_CONTROL1_HASH_SELECT_SHA1	(0 << 16)
167 #define MXS_DCP_CONTROL1_CIPHER_MODE_CBC	(1 << 4)
168 #define MXS_DCP_CONTROL1_CIPHER_MODE_ECB	(0 << 4)
169 #define MXS_DCP_CONTROL1_CIPHER_SELECT_AES128	(0 << 0)
170 
171 static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
172 {
173 	struct dcp *sdcp = global_sdcp;
174 	const int chan = actx->chan;
175 	uint32_t stat;
176 	unsigned long ret;
177 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
178 
179 	dma_addr_t desc_phys = dma_map_single(sdcp->dev, desc, sizeof(*desc),
180 					      DMA_TO_DEVICE);
181 
182 	reinit_completion(&sdcp->completion[chan]);
183 
184 	/* Clear status register. */
185 	writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(chan));
186 
187 	/* Load the DMA descriptor. */
188 	writel(desc_phys, sdcp->base + MXS_DCP_CH_N_CMDPTR(chan));
189 
190 	/* Increment the semaphore to start the DMA transfer. */
191 	writel(1, sdcp->base + MXS_DCP_CH_N_SEMA(chan));
192 
193 	ret = wait_for_completion_timeout(&sdcp->completion[chan],
194 					  msecs_to_jiffies(1000));
195 	if (!ret) {
196 		dev_err(sdcp->dev, "Channel %i timeout (DCP_STAT=0x%08x)\n",
197 			chan, readl(sdcp->base + MXS_DCP_STAT));
198 		return -ETIMEDOUT;
199 	}
200 
201 	stat = readl(sdcp->base + MXS_DCP_CH_N_STAT(chan));
202 	if (stat & 0xff) {
203 		dev_err(sdcp->dev, "Channel %i error (CH_STAT=0x%08x)\n",
204 			chan, stat);
205 		return -EINVAL;
206 	}
207 
208 	dma_unmap_single(sdcp->dev, desc_phys, sizeof(*desc), DMA_TO_DEVICE);
209 
210 	return 0;
211 }
212 
213 /*
214  * Encryption (AES128)
215  */
216 static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
217 			   struct skcipher_request *req, int init)
218 {
219 	struct dcp *sdcp = global_sdcp;
220 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
221 	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
222 	int ret;
223 
224 	dma_addr_t key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
225 					     2 * AES_KEYSIZE_128,
226 					     DMA_TO_DEVICE);
227 	dma_addr_t src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
228 					     DCP_BUF_SZ, DMA_TO_DEVICE);
229 	dma_addr_t dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
230 					     DCP_BUF_SZ, DMA_FROM_DEVICE);
231 
232 	if (actx->fill % AES_BLOCK_SIZE) {
233 		dev_err(sdcp->dev, "Invalid block size!\n");
234 		ret = -EINVAL;
235 		goto aes_done_run;
236 	}
237 
238 	/* Fill in the DMA descriptor. */
239 	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
240 		    MXS_DCP_CONTROL0_INTERRUPT |
241 		    MXS_DCP_CONTROL0_ENABLE_CIPHER;
242 
243 	/* Payload contains the key. */
244 	desc->control0 |= MXS_DCP_CONTROL0_PAYLOAD_KEY;
245 
246 	if (rctx->enc)
247 		desc->control0 |= MXS_DCP_CONTROL0_CIPHER_ENCRYPT;
248 	if (init)
249 		desc->control0 |= MXS_DCP_CONTROL0_CIPHER_INIT;
250 
251 	desc->control1 = MXS_DCP_CONTROL1_CIPHER_SELECT_AES128;
252 
253 	if (rctx->ecb)
254 		desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_ECB;
255 	else
256 		desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_CBC;
257 
258 	desc->next_cmd_addr = 0;
259 	desc->source = src_phys;
260 	desc->destination = dst_phys;
261 	desc->size = actx->fill;
262 	desc->payload = key_phys;
263 	desc->status = 0;
264 
265 	ret = mxs_dcp_start_dma(actx);
266 
267 aes_done_run:
268 	dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
269 			 DMA_TO_DEVICE);
270 	dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
271 	dma_unmap_single(sdcp->dev, dst_phys, DCP_BUF_SZ, DMA_FROM_DEVICE);
272 
273 	return ret;
274 }
275 
276 static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
277 {
278 	struct dcp *sdcp = global_sdcp;
279 
280 	struct skcipher_request *req = skcipher_request_cast(arq);
281 	struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
282 	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
283 
284 	struct scatterlist *dst = req->dst;
285 	struct scatterlist *src = req->src;
286 	const int nents = sg_nents(req->src);
287 
288 	const int out_off = DCP_BUF_SZ;
289 	uint8_t *in_buf = sdcp->coh->aes_in_buf;
290 	uint8_t *out_buf = sdcp->coh->aes_out_buf;
291 
292 	uint8_t *out_tmp, *src_buf, *dst_buf = NULL;
293 	uint32_t dst_off = 0;
294 	uint32_t last_out_len = 0;
295 
296 	uint8_t *key = sdcp->coh->aes_key;
297 
298 	int ret = 0;
299 	int split = 0;
300 	unsigned int i, len, clen, rem = 0, tlen = 0;
301 	int init = 0;
302 	bool limit_hit = false;
303 
304 	actx->fill = 0;
305 
306 	/* Copy the key from the temporary location. */
307 	memcpy(key, actx->key, actx->key_len);
308 
309 	if (!rctx->ecb) {
310 		/* Copy the CBC IV just past the key. */
311 		memcpy(key + AES_KEYSIZE_128, req->iv, AES_KEYSIZE_128);
312 		/* CBC needs the INIT set. */
313 		init = 1;
314 	} else {
315 		memset(key + AES_KEYSIZE_128, 0, AES_KEYSIZE_128);
316 	}
317 
318 	for_each_sg(req->src, src, nents, i) {
319 		src_buf = sg_virt(src);
320 		len = sg_dma_len(src);
321 		tlen += len;
322 		limit_hit = tlen > req->cryptlen;
323 
324 		if (limit_hit)
325 			len = req->cryptlen - (tlen - len);
326 
327 		do {
328 			if (actx->fill + len > out_off)
329 				clen = out_off - actx->fill;
330 			else
331 				clen = len;
332 
333 			memcpy(in_buf + actx->fill, src_buf, clen);
334 			len -= clen;
335 			src_buf += clen;
336 			actx->fill += clen;
337 
338 			/*
339 			 * If we filled the buffer or this is the last SG,
340 			 * submit the buffer.
341 			 */
342 			if (actx->fill == out_off || sg_is_last(src) ||
343 				limit_hit) {
344 				ret = mxs_dcp_run_aes(actx, req, init);
345 				if (ret)
346 					return ret;
347 				init = 0;
348 
349 				out_tmp = out_buf;
350 				last_out_len = actx->fill;
351 				while (dst && actx->fill) {
352 					if (!split) {
353 						dst_buf = sg_virt(dst);
354 						dst_off = 0;
355 					}
356 					rem = min(sg_dma_len(dst) - dst_off,
357 						  actx->fill);
358 
359 					memcpy(dst_buf + dst_off, out_tmp, rem);
360 					out_tmp += rem;
361 					dst_off += rem;
362 					actx->fill -= rem;
363 
364 					if (dst_off == sg_dma_len(dst)) {
365 						dst = sg_next(dst);
366 						split = 0;
367 					} else {
368 						split = 1;
369 					}
370 				}
371 			}
372 		} while (len);
373 
374 		if (limit_hit)
375 			break;
376 	}
377 
378 	/* Copy the IV for CBC for chaining */
379 	if (!rctx->ecb) {
380 		if (rctx->enc)
381 			memcpy(req->iv, out_buf+(last_out_len-AES_BLOCK_SIZE),
382 				AES_BLOCK_SIZE);
383 		else
384 			memcpy(req->iv, in_buf+(last_out_len-AES_BLOCK_SIZE),
385 				AES_BLOCK_SIZE);
386 	}
387 
388 	return ret;
389 }
390 
391 static int dcp_chan_thread_aes(void *data)
392 {
393 	struct dcp *sdcp = global_sdcp;
394 	const int chan = DCP_CHAN_CRYPTO;
395 
396 	struct crypto_async_request *backlog;
397 	struct crypto_async_request *arq;
398 
399 	int ret;
400 
401 	while (!kthread_should_stop()) {
402 		set_current_state(TASK_INTERRUPTIBLE);
403 
404 		spin_lock(&sdcp->lock[chan]);
405 		backlog = crypto_get_backlog(&sdcp->queue[chan]);
406 		arq = crypto_dequeue_request(&sdcp->queue[chan]);
407 		spin_unlock(&sdcp->lock[chan]);
408 
409 		if (!backlog && !arq) {
410 			schedule();
411 			continue;
412 		}
413 
414 		set_current_state(TASK_RUNNING);
415 
416 		if (backlog)
417 			backlog->complete(backlog, -EINPROGRESS);
418 
419 		if (arq) {
420 			ret = mxs_dcp_aes_block_crypt(arq);
421 			arq->complete(arq, ret);
422 		}
423 	}
424 
425 	return 0;
426 }
427 
428 static int mxs_dcp_block_fallback(struct skcipher_request *req, int enc)
429 {
430 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
431 	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
432 	struct dcp_async_ctx *ctx = crypto_skcipher_ctx(tfm);
433 	int ret;
434 
435 	skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback);
436 	skcipher_request_set_callback(&rctx->fallback_req, req->base.flags,
437 				      req->base.complete, req->base.data);
438 	skcipher_request_set_crypt(&rctx->fallback_req, req->src, req->dst,
439 				   req->cryptlen, req->iv);
440 
441 	if (enc)
442 		ret = crypto_skcipher_encrypt(&rctx->fallback_req);
443 	else
444 		ret = crypto_skcipher_decrypt(&rctx->fallback_req);
445 
446 	return ret;
447 }
448 
449 static int mxs_dcp_aes_enqueue(struct skcipher_request *req, int enc, int ecb)
450 {
451 	struct dcp *sdcp = global_sdcp;
452 	struct crypto_async_request *arq = &req->base;
453 	struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
454 	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
455 	int ret;
456 
457 	if (unlikely(actx->key_len != AES_KEYSIZE_128))
458 		return mxs_dcp_block_fallback(req, enc);
459 
460 	rctx->enc = enc;
461 	rctx->ecb = ecb;
462 	actx->chan = DCP_CHAN_CRYPTO;
463 
464 	spin_lock(&sdcp->lock[actx->chan]);
465 	ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
466 	spin_unlock(&sdcp->lock[actx->chan]);
467 
468 	wake_up_process(sdcp->thread[actx->chan]);
469 
470 	return ret;
471 }
472 
473 static int mxs_dcp_aes_ecb_decrypt(struct skcipher_request *req)
474 {
475 	return mxs_dcp_aes_enqueue(req, 0, 1);
476 }
477 
478 static int mxs_dcp_aes_ecb_encrypt(struct skcipher_request *req)
479 {
480 	return mxs_dcp_aes_enqueue(req, 1, 1);
481 }
482 
483 static int mxs_dcp_aes_cbc_decrypt(struct skcipher_request *req)
484 {
485 	return mxs_dcp_aes_enqueue(req, 0, 0);
486 }
487 
488 static int mxs_dcp_aes_cbc_encrypt(struct skcipher_request *req)
489 {
490 	return mxs_dcp_aes_enqueue(req, 1, 0);
491 }
492 
493 static int mxs_dcp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
494 			      unsigned int len)
495 {
496 	struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
497 
498 	/*
499 	 * AES 128 is supposed by the hardware, store key into temporary
500 	 * buffer and exit. We must use the temporary buffer here, since
501 	 * there can still be an operation in progress.
502 	 */
503 	actx->key_len = len;
504 	if (len == AES_KEYSIZE_128) {
505 		memcpy(actx->key, key, len);
506 		return 0;
507 	}
508 
509 	/*
510 	 * If the requested AES key size is not supported by the hardware,
511 	 * but is supported by in-kernel software implementation, we use
512 	 * software fallback.
513 	 */
514 	crypto_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK);
515 	crypto_skcipher_set_flags(actx->fallback,
516 				  tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
517 	return crypto_skcipher_setkey(actx->fallback, key, len);
518 }
519 
520 static int mxs_dcp_aes_fallback_init_tfm(struct crypto_skcipher *tfm)
521 {
522 	const char *name = crypto_tfm_alg_name(crypto_skcipher_tfm(tfm));
523 	struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
524 	struct crypto_skcipher *blk;
525 
526 	blk = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
527 	if (IS_ERR(blk))
528 		return PTR_ERR(blk);
529 
530 	actx->fallback = blk;
531 	crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx) +
532 					 crypto_skcipher_reqsize(blk));
533 	return 0;
534 }
535 
536 static void mxs_dcp_aes_fallback_exit_tfm(struct crypto_skcipher *tfm)
537 {
538 	struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
539 
540 	crypto_free_skcipher(actx->fallback);
541 }
542 
543 /*
544  * Hashing (SHA1/SHA256)
545  */
546 static int mxs_dcp_run_sha(struct ahash_request *req)
547 {
548 	struct dcp *sdcp = global_sdcp;
549 	int ret;
550 
551 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
552 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
553 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
554 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
555 
556 	dma_addr_t digest_phys = 0;
557 	dma_addr_t buf_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_in_buf,
558 					     DCP_BUF_SZ, DMA_TO_DEVICE);
559 
560 	/* Fill in the DMA descriptor. */
561 	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
562 		    MXS_DCP_CONTROL0_INTERRUPT |
563 		    MXS_DCP_CONTROL0_ENABLE_HASH;
564 	if (rctx->init)
565 		desc->control0 |= MXS_DCP_CONTROL0_HASH_INIT;
566 
567 	desc->control1 = actx->alg;
568 	desc->next_cmd_addr = 0;
569 	desc->source = buf_phys;
570 	desc->destination = 0;
571 	desc->size = actx->fill;
572 	desc->payload = 0;
573 	desc->status = 0;
574 
575 	/*
576 	 * Align driver with hw behavior when generating null hashes
577 	 */
578 	if (rctx->init && rctx->fini && desc->size == 0) {
579 		struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
580 		const uint8_t *sha_buf =
581 			(actx->alg == MXS_DCP_CONTROL1_HASH_SELECT_SHA1) ?
582 			sha1_null_hash : sha256_null_hash;
583 		memcpy(sdcp->coh->sha_out_buf, sha_buf, halg->digestsize);
584 		ret = 0;
585 		goto done_run;
586 	}
587 
588 	/* Set HASH_TERM bit for last transfer block. */
589 	if (rctx->fini) {
590 		digest_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_out_buf,
591 					     DCP_SHA_PAY_SZ, DMA_FROM_DEVICE);
592 		desc->control0 |= MXS_DCP_CONTROL0_HASH_TERM;
593 		desc->payload = digest_phys;
594 	}
595 
596 	ret = mxs_dcp_start_dma(actx);
597 
598 	if (rctx->fini)
599 		dma_unmap_single(sdcp->dev, digest_phys, DCP_SHA_PAY_SZ,
600 				 DMA_FROM_DEVICE);
601 
602 done_run:
603 	dma_unmap_single(sdcp->dev, buf_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
604 
605 	return ret;
606 }
607 
608 static int dcp_sha_req_to_buf(struct crypto_async_request *arq)
609 {
610 	struct dcp *sdcp = global_sdcp;
611 
612 	struct ahash_request *req = ahash_request_cast(arq);
613 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
614 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
615 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
616 	struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
617 
618 	uint8_t *in_buf = sdcp->coh->sha_in_buf;
619 	uint8_t *out_buf = sdcp->coh->sha_out_buf;
620 
621 	struct scatterlist *src;
622 
623 	unsigned int i, len, clen, oft = 0;
624 	int ret;
625 
626 	int fin = rctx->fini;
627 	if (fin)
628 		rctx->fini = 0;
629 
630 	src = req->src;
631 	len = req->nbytes;
632 
633 	while (len) {
634 		if (actx->fill + len > DCP_BUF_SZ)
635 			clen = DCP_BUF_SZ - actx->fill;
636 		else
637 			clen = len;
638 
639 		scatterwalk_map_and_copy(in_buf + actx->fill, src, oft, clen,
640 					 0);
641 
642 		len -= clen;
643 		oft += clen;
644 		actx->fill += clen;
645 
646 		/*
647 		 * If we filled the buffer and still have some
648 		 * more data, submit the buffer.
649 		 */
650 		if (len && actx->fill == DCP_BUF_SZ) {
651 			ret = mxs_dcp_run_sha(req);
652 			if (ret)
653 				return ret;
654 			actx->fill = 0;
655 			rctx->init = 0;
656 		}
657 	}
658 
659 	if (fin) {
660 		rctx->fini = 1;
661 
662 		/* Submit whatever is left. */
663 		if (!req->result)
664 			return -EINVAL;
665 
666 		ret = mxs_dcp_run_sha(req);
667 		if (ret)
668 			return ret;
669 
670 		actx->fill = 0;
671 
672 		/* For some reason the result is flipped */
673 		for (i = 0; i < halg->digestsize; i++)
674 			req->result[i] = out_buf[halg->digestsize - i - 1];
675 	}
676 
677 	return 0;
678 }
679 
680 static int dcp_chan_thread_sha(void *data)
681 {
682 	struct dcp *sdcp = global_sdcp;
683 	const int chan = DCP_CHAN_HASH_SHA;
684 
685 	struct crypto_async_request *backlog;
686 	struct crypto_async_request *arq;
687 	int ret;
688 
689 	while (!kthread_should_stop()) {
690 		set_current_state(TASK_INTERRUPTIBLE);
691 
692 		spin_lock(&sdcp->lock[chan]);
693 		backlog = crypto_get_backlog(&sdcp->queue[chan]);
694 		arq = crypto_dequeue_request(&sdcp->queue[chan]);
695 		spin_unlock(&sdcp->lock[chan]);
696 
697 		if (!backlog && !arq) {
698 			schedule();
699 			continue;
700 		}
701 
702 		set_current_state(TASK_RUNNING);
703 
704 		if (backlog)
705 			backlog->complete(backlog, -EINPROGRESS);
706 
707 		if (arq) {
708 			ret = dcp_sha_req_to_buf(arq);
709 			arq->complete(arq, ret);
710 		}
711 	}
712 
713 	return 0;
714 }
715 
716 static int dcp_sha_init(struct ahash_request *req)
717 {
718 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
719 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
720 
721 	struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
722 
723 	/*
724 	 * Start hashing session. The code below only inits the
725 	 * hashing session context, nothing more.
726 	 */
727 	memset(actx, 0, sizeof(*actx));
728 
729 	if (strcmp(halg->base.cra_name, "sha1") == 0)
730 		actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA1;
731 	else
732 		actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA256;
733 
734 	actx->fill = 0;
735 	actx->hot = 0;
736 	actx->chan = DCP_CHAN_HASH_SHA;
737 
738 	mutex_init(&actx->mutex);
739 
740 	return 0;
741 }
742 
743 static int dcp_sha_update_fx(struct ahash_request *req, int fini)
744 {
745 	struct dcp *sdcp = global_sdcp;
746 
747 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
748 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
749 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
750 
751 	int ret;
752 
753 	/*
754 	 * Ignore requests that have no data in them and are not
755 	 * the trailing requests in the stream of requests.
756 	 */
757 	if (!req->nbytes && !fini)
758 		return 0;
759 
760 	mutex_lock(&actx->mutex);
761 
762 	rctx->fini = fini;
763 
764 	if (!actx->hot) {
765 		actx->hot = 1;
766 		rctx->init = 1;
767 	}
768 
769 	spin_lock(&sdcp->lock[actx->chan]);
770 	ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
771 	spin_unlock(&sdcp->lock[actx->chan]);
772 
773 	wake_up_process(sdcp->thread[actx->chan]);
774 	mutex_unlock(&actx->mutex);
775 
776 	return ret;
777 }
778 
779 static int dcp_sha_update(struct ahash_request *req)
780 {
781 	return dcp_sha_update_fx(req, 0);
782 }
783 
784 static int dcp_sha_final(struct ahash_request *req)
785 {
786 	ahash_request_set_crypt(req, NULL, req->result, 0);
787 	req->nbytes = 0;
788 	return dcp_sha_update_fx(req, 1);
789 }
790 
791 static int dcp_sha_finup(struct ahash_request *req)
792 {
793 	return dcp_sha_update_fx(req, 1);
794 }
795 
796 static int dcp_sha_digest(struct ahash_request *req)
797 {
798 	int ret;
799 
800 	ret = dcp_sha_init(req);
801 	if (ret)
802 		return ret;
803 
804 	return dcp_sha_finup(req);
805 }
806 
807 static int dcp_sha_import(struct ahash_request *req, const void *in)
808 {
809 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
810 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
811 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
812 	const struct dcp_export_state *export = in;
813 
814 	memset(rctx, 0, sizeof(struct dcp_sha_req_ctx));
815 	memset(actx, 0, sizeof(struct dcp_async_ctx));
816 	memcpy(rctx, &export->req_ctx, sizeof(struct dcp_sha_req_ctx));
817 	memcpy(actx, &export->async_ctx, sizeof(struct dcp_async_ctx));
818 
819 	return 0;
820 }
821 
822 static int dcp_sha_export(struct ahash_request *req, void *out)
823 {
824 	struct dcp_sha_req_ctx *rctx_state = ahash_request_ctx(req);
825 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
826 	struct dcp_async_ctx *actx_state = crypto_ahash_ctx(tfm);
827 	struct dcp_export_state *export = out;
828 
829 	memcpy(&export->req_ctx, rctx_state, sizeof(struct dcp_sha_req_ctx));
830 	memcpy(&export->async_ctx, actx_state, sizeof(struct dcp_async_ctx));
831 
832 	return 0;
833 }
834 
835 static int dcp_sha_cra_init(struct crypto_tfm *tfm)
836 {
837 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
838 				 sizeof(struct dcp_sha_req_ctx));
839 	return 0;
840 }
841 
842 static void dcp_sha_cra_exit(struct crypto_tfm *tfm)
843 {
844 }
845 
846 /* AES 128 ECB and AES 128 CBC */
847 static struct skcipher_alg dcp_aes_algs[] = {
848 	{
849 		.base.cra_name		= "ecb(aes)",
850 		.base.cra_driver_name	= "ecb-aes-dcp",
851 		.base.cra_priority	= 400,
852 		.base.cra_alignmask	= 15,
853 		.base.cra_flags		= CRYPTO_ALG_ASYNC |
854 					  CRYPTO_ALG_NEED_FALLBACK,
855 		.base.cra_blocksize	= AES_BLOCK_SIZE,
856 		.base.cra_ctxsize	= sizeof(struct dcp_async_ctx),
857 		.base.cra_module	= THIS_MODULE,
858 
859 		.min_keysize		= AES_MIN_KEY_SIZE,
860 		.max_keysize		= AES_MAX_KEY_SIZE,
861 		.setkey			= mxs_dcp_aes_setkey,
862 		.encrypt		= mxs_dcp_aes_ecb_encrypt,
863 		.decrypt		= mxs_dcp_aes_ecb_decrypt,
864 		.init			= mxs_dcp_aes_fallback_init_tfm,
865 		.exit			= mxs_dcp_aes_fallback_exit_tfm,
866 	}, {
867 		.base.cra_name		= "cbc(aes)",
868 		.base.cra_driver_name	= "cbc-aes-dcp",
869 		.base.cra_priority	= 400,
870 		.base.cra_alignmask	= 15,
871 		.base.cra_flags		= CRYPTO_ALG_ASYNC |
872 					  CRYPTO_ALG_NEED_FALLBACK,
873 		.base.cra_blocksize	= AES_BLOCK_SIZE,
874 		.base.cra_ctxsize	= sizeof(struct dcp_async_ctx),
875 		.base.cra_module	= THIS_MODULE,
876 
877 		.min_keysize		= AES_MIN_KEY_SIZE,
878 		.max_keysize		= AES_MAX_KEY_SIZE,
879 		.setkey			= mxs_dcp_aes_setkey,
880 		.encrypt		= mxs_dcp_aes_cbc_encrypt,
881 		.decrypt		= mxs_dcp_aes_cbc_decrypt,
882 		.ivsize			= AES_BLOCK_SIZE,
883 		.init			= mxs_dcp_aes_fallback_init_tfm,
884 		.exit			= mxs_dcp_aes_fallback_exit_tfm,
885 	},
886 };
887 
888 /* SHA1 */
889 static struct ahash_alg dcp_sha1_alg = {
890 	.init	= dcp_sha_init,
891 	.update	= dcp_sha_update,
892 	.final	= dcp_sha_final,
893 	.finup	= dcp_sha_finup,
894 	.digest	= dcp_sha_digest,
895 	.import = dcp_sha_import,
896 	.export = dcp_sha_export,
897 	.halg	= {
898 		.digestsize	= SHA1_DIGEST_SIZE,
899 		.statesize	= sizeof(struct dcp_export_state),
900 		.base		= {
901 			.cra_name		= "sha1",
902 			.cra_driver_name	= "sha1-dcp",
903 			.cra_priority		= 400,
904 			.cra_alignmask		= 63,
905 			.cra_flags		= CRYPTO_ALG_ASYNC,
906 			.cra_blocksize		= SHA1_BLOCK_SIZE,
907 			.cra_ctxsize		= sizeof(struct dcp_async_ctx),
908 			.cra_module		= THIS_MODULE,
909 			.cra_init		= dcp_sha_cra_init,
910 			.cra_exit		= dcp_sha_cra_exit,
911 		},
912 	},
913 };
914 
915 /* SHA256 */
916 static struct ahash_alg dcp_sha256_alg = {
917 	.init	= dcp_sha_init,
918 	.update	= dcp_sha_update,
919 	.final	= dcp_sha_final,
920 	.finup	= dcp_sha_finup,
921 	.digest	= dcp_sha_digest,
922 	.import = dcp_sha_import,
923 	.export = dcp_sha_export,
924 	.halg	= {
925 		.digestsize	= SHA256_DIGEST_SIZE,
926 		.statesize	= sizeof(struct dcp_export_state),
927 		.base		= {
928 			.cra_name		= "sha256",
929 			.cra_driver_name	= "sha256-dcp",
930 			.cra_priority		= 400,
931 			.cra_alignmask		= 63,
932 			.cra_flags		= CRYPTO_ALG_ASYNC,
933 			.cra_blocksize		= SHA256_BLOCK_SIZE,
934 			.cra_ctxsize		= sizeof(struct dcp_async_ctx),
935 			.cra_module		= THIS_MODULE,
936 			.cra_init		= dcp_sha_cra_init,
937 			.cra_exit		= dcp_sha_cra_exit,
938 		},
939 	},
940 };
941 
942 static irqreturn_t mxs_dcp_irq(int irq, void *context)
943 {
944 	struct dcp *sdcp = context;
945 	uint32_t stat;
946 	int i;
947 
948 	stat = readl(sdcp->base + MXS_DCP_STAT);
949 	stat &= MXS_DCP_STAT_IRQ_MASK;
950 	if (!stat)
951 		return IRQ_NONE;
952 
953 	/* Clear the interrupts. */
954 	writel(stat, sdcp->base + MXS_DCP_STAT_CLR);
955 
956 	/* Complete the DMA requests that finished. */
957 	for (i = 0; i < DCP_MAX_CHANS; i++)
958 		if (stat & (1 << i))
959 			complete(&sdcp->completion[i]);
960 
961 	return IRQ_HANDLED;
962 }
963 
964 static int mxs_dcp_probe(struct platform_device *pdev)
965 {
966 	struct device *dev = &pdev->dev;
967 	struct dcp *sdcp = NULL;
968 	int i, ret;
969 	int dcp_vmi_irq, dcp_irq;
970 
971 	if (global_sdcp) {
972 		dev_err(dev, "Only one DCP instance allowed!\n");
973 		return -ENODEV;
974 	}
975 
976 	dcp_vmi_irq = platform_get_irq(pdev, 0);
977 	if (dcp_vmi_irq < 0)
978 		return dcp_vmi_irq;
979 
980 	dcp_irq = platform_get_irq(pdev, 1);
981 	if (dcp_irq < 0)
982 		return dcp_irq;
983 
984 	sdcp = devm_kzalloc(dev, sizeof(*sdcp), GFP_KERNEL);
985 	if (!sdcp)
986 		return -ENOMEM;
987 
988 	sdcp->dev = dev;
989 	sdcp->base = devm_platform_ioremap_resource(pdev, 0);
990 	if (IS_ERR(sdcp->base))
991 		return PTR_ERR(sdcp->base);
992 
993 
994 	ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
995 			       "dcp-vmi-irq", sdcp);
996 	if (ret) {
997 		dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
998 		return ret;
999 	}
1000 
1001 	ret = devm_request_irq(dev, dcp_irq, mxs_dcp_irq, 0,
1002 			       "dcp-irq", sdcp);
1003 	if (ret) {
1004 		dev_err(dev, "Failed to claim DCP IRQ!\n");
1005 		return ret;
1006 	}
1007 
1008 	/* Allocate coherent helper block. */
1009 	sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh) + DCP_ALIGNMENT,
1010 				   GFP_KERNEL);
1011 	if (!sdcp->coh)
1012 		return -ENOMEM;
1013 
1014 	/* Re-align the structure so it fits the DCP constraints. */
1015 	sdcp->coh = PTR_ALIGN(sdcp->coh, DCP_ALIGNMENT);
1016 
1017 	/* DCP clock is optional, only used on some SOCs */
1018 	sdcp->dcp_clk = devm_clk_get(dev, "dcp");
1019 	if (IS_ERR(sdcp->dcp_clk)) {
1020 		if (sdcp->dcp_clk != ERR_PTR(-ENOENT))
1021 			return PTR_ERR(sdcp->dcp_clk);
1022 		sdcp->dcp_clk = NULL;
1023 	}
1024 	ret = clk_prepare_enable(sdcp->dcp_clk);
1025 	if (ret)
1026 		return ret;
1027 
1028 	/* Restart the DCP block. */
1029 	ret = stmp_reset_block(sdcp->base);
1030 	if (ret) {
1031 		dev_err(dev, "Failed reset\n");
1032 		goto err_disable_unprepare_clk;
1033 	}
1034 
1035 	/* Initialize control register. */
1036 	writel(MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES |
1037 	       MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING | 0xf,
1038 	       sdcp->base + MXS_DCP_CTRL);
1039 
1040 	/* Enable all DCP DMA channels. */
1041 	writel(MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK,
1042 	       sdcp->base + MXS_DCP_CHANNELCTRL);
1043 
1044 	/*
1045 	 * We do not enable context switching. Give the context buffer a
1046 	 * pointer to an illegal address so if context switching is
1047 	 * inadvertantly enabled, the DCP will return an error instead of
1048 	 * trashing good memory. The DCP DMA cannot access ROM, so any ROM
1049 	 * address will do.
1050 	 */
1051 	writel(0xffff0000, sdcp->base + MXS_DCP_CONTEXT);
1052 	for (i = 0; i < DCP_MAX_CHANS; i++)
1053 		writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(i));
1054 	writel(0xffffffff, sdcp->base + MXS_DCP_STAT_CLR);
1055 
1056 	global_sdcp = sdcp;
1057 
1058 	platform_set_drvdata(pdev, sdcp);
1059 
1060 	for (i = 0; i < DCP_MAX_CHANS; i++) {
1061 		spin_lock_init(&sdcp->lock[i]);
1062 		init_completion(&sdcp->completion[i]);
1063 		crypto_init_queue(&sdcp->queue[i], 50);
1064 	}
1065 
1066 	/* Create the SHA and AES handler threads. */
1067 	sdcp->thread[DCP_CHAN_HASH_SHA] = kthread_run(dcp_chan_thread_sha,
1068 						      NULL, "mxs_dcp_chan/sha");
1069 	if (IS_ERR(sdcp->thread[DCP_CHAN_HASH_SHA])) {
1070 		dev_err(dev, "Error starting SHA thread!\n");
1071 		ret = PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
1072 		goto err_disable_unprepare_clk;
1073 	}
1074 
1075 	sdcp->thread[DCP_CHAN_CRYPTO] = kthread_run(dcp_chan_thread_aes,
1076 						    NULL, "mxs_dcp_chan/aes");
1077 	if (IS_ERR(sdcp->thread[DCP_CHAN_CRYPTO])) {
1078 		dev_err(dev, "Error starting SHA thread!\n");
1079 		ret = PTR_ERR(sdcp->thread[DCP_CHAN_CRYPTO]);
1080 		goto err_destroy_sha_thread;
1081 	}
1082 
1083 	/* Register the various crypto algorithms. */
1084 	sdcp->caps = readl(sdcp->base + MXS_DCP_CAPABILITY1);
1085 
1086 	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128) {
1087 		ret = crypto_register_skciphers(dcp_aes_algs,
1088 						ARRAY_SIZE(dcp_aes_algs));
1089 		if (ret) {
1090 			/* Failed to register algorithm. */
1091 			dev_err(dev, "Failed to register AES crypto!\n");
1092 			goto err_destroy_aes_thread;
1093 		}
1094 	}
1095 
1096 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1) {
1097 		ret = crypto_register_ahash(&dcp_sha1_alg);
1098 		if (ret) {
1099 			dev_err(dev, "Failed to register %s hash!\n",
1100 				dcp_sha1_alg.halg.base.cra_name);
1101 			goto err_unregister_aes;
1102 		}
1103 	}
1104 
1105 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256) {
1106 		ret = crypto_register_ahash(&dcp_sha256_alg);
1107 		if (ret) {
1108 			dev_err(dev, "Failed to register %s hash!\n",
1109 				dcp_sha256_alg.halg.base.cra_name);
1110 			goto err_unregister_sha1;
1111 		}
1112 	}
1113 
1114 	return 0;
1115 
1116 err_unregister_sha1:
1117 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1118 		crypto_unregister_ahash(&dcp_sha1_alg);
1119 
1120 err_unregister_aes:
1121 	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1122 		crypto_unregister_skciphers(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1123 
1124 err_destroy_aes_thread:
1125 	kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1126 
1127 err_destroy_sha_thread:
1128 	kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1129 
1130 err_disable_unprepare_clk:
1131 	clk_disable_unprepare(sdcp->dcp_clk);
1132 
1133 	return ret;
1134 }
1135 
1136 static int mxs_dcp_remove(struct platform_device *pdev)
1137 {
1138 	struct dcp *sdcp = platform_get_drvdata(pdev);
1139 
1140 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256)
1141 		crypto_unregister_ahash(&dcp_sha256_alg);
1142 
1143 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1144 		crypto_unregister_ahash(&dcp_sha1_alg);
1145 
1146 	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1147 		crypto_unregister_skciphers(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1148 
1149 	kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1150 	kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1151 
1152 	clk_disable_unprepare(sdcp->dcp_clk);
1153 
1154 	platform_set_drvdata(pdev, NULL);
1155 
1156 	global_sdcp = NULL;
1157 
1158 	return 0;
1159 }
1160 
1161 static const struct of_device_id mxs_dcp_dt_ids[] = {
1162 	{ .compatible = "fsl,imx23-dcp", .data = NULL, },
1163 	{ .compatible = "fsl,imx28-dcp", .data = NULL, },
1164 	{ /* sentinel */ }
1165 };
1166 
1167 MODULE_DEVICE_TABLE(of, mxs_dcp_dt_ids);
1168 
1169 static struct platform_driver mxs_dcp_driver = {
1170 	.probe	= mxs_dcp_probe,
1171 	.remove	= mxs_dcp_remove,
1172 	.driver	= {
1173 		.name		= "mxs-dcp",
1174 		.of_match_table	= mxs_dcp_dt_ids,
1175 	},
1176 };
1177 
1178 module_platform_driver(mxs_dcp_driver);
1179 
1180 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
1181 MODULE_DESCRIPTION("Freescale MXS DCP Driver");
1182 MODULE_LICENSE("GPL");
1183 MODULE_ALIAS("platform:mxs-dcp");
1184