xref: /openbmc/linux/drivers/crypto/mxs-dcp.c (revision 3e30a927)
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/sha.h>
21 #include <crypto/internal/hash.h>
22 #include <crypto/internal/skcipher.h>
23 
24 #define DCP_MAX_CHANS	4
25 #define DCP_BUF_SZ	PAGE_SIZE
26 #define DCP_SHA_PAY_SZ  64
27 
28 #define DCP_ALIGNMENT	64
29 
30 /*
31  * Null hashes to align with hw behavior on imx6sl and ull
32  * these are flipped for consistency with hw output
33  */
34 static const uint8_t sha1_null_hash[] =
35 	"\x09\x07\xd8\xaf\x90\x18\x60\x95\xef\xbf"
36 	"\x55\x32\x0d\x4b\x6b\x5e\xee\xa3\x39\xda";
37 
38 static const uint8_t sha256_null_hash[] =
39 	"\x55\xb8\x52\x78\x1b\x99\x95\xa4"
40 	"\x4c\x93\x9b\x64\xe4\x41\xae\x27"
41 	"\x24\xb9\x6f\x99\xc8\xf4\xfb\x9a"
42 	"\x14\x1c\xfc\x98\x42\xc4\xb0\xe3";
43 
44 /* DCP DMA descriptor. */
45 struct dcp_dma_desc {
46 	uint32_t	next_cmd_addr;
47 	uint32_t	control0;
48 	uint32_t	control1;
49 	uint32_t	source;
50 	uint32_t	destination;
51 	uint32_t	size;
52 	uint32_t	payload;
53 	uint32_t	status;
54 };
55 
56 /* Coherent aligned block for bounce buffering. */
57 struct dcp_coherent_block {
58 	uint8_t			aes_in_buf[DCP_BUF_SZ];
59 	uint8_t			aes_out_buf[DCP_BUF_SZ];
60 	uint8_t			sha_in_buf[DCP_BUF_SZ];
61 	uint8_t			sha_out_buf[DCP_SHA_PAY_SZ];
62 
63 	uint8_t			aes_key[2 * AES_KEYSIZE_128];
64 
65 	struct dcp_dma_desc	desc[DCP_MAX_CHANS];
66 };
67 
68 struct dcp {
69 	struct device			*dev;
70 	void __iomem			*base;
71 
72 	uint32_t			caps;
73 
74 	struct dcp_coherent_block	*coh;
75 
76 	struct completion		completion[DCP_MAX_CHANS];
77 	spinlock_t			lock[DCP_MAX_CHANS];
78 	struct task_struct		*thread[DCP_MAX_CHANS];
79 	struct crypto_queue		queue[DCP_MAX_CHANS];
80 	struct clk			*dcp_clk;
81 };
82 
83 enum dcp_chan {
84 	DCP_CHAN_HASH_SHA	= 0,
85 	DCP_CHAN_CRYPTO		= 2,
86 };
87 
88 struct dcp_async_ctx {
89 	/* Common context */
90 	enum dcp_chan	chan;
91 	uint32_t	fill;
92 
93 	/* SHA Hash-specific context */
94 	struct mutex			mutex;
95 	uint32_t			alg;
96 	unsigned int			hot:1;
97 
98 	/* Crypto-specific context */
99 	struct crypto_sync_skcipher	*fallback;
100 	unsigned int			key_len;
101 	uint8_t				key[AES_KEYSIZE_128];
102 };
103 
104 struct dcp_aes_req_ctx {
105 	unsigned int	enc:1;
106 	unsigned int	ecb:1;
107 };
108 
109 struct dcp_sha_req_ctx {
110 	unsigned int	init:1;
111 	unsigned int	fini:1;
112 };
113 
114 struct dcp_export_state {
115 	struct dcp_sha_req_ctx req_ctx;
116 	struct dcp_async_ctx async_ctx;
117 };
118 
119 /*
120  * There can even be only one instance of the MXS DCP due to the
121  * design of Linux Crypto API.
122  */
123 static struct dcp *global_sdcp;
124 
125 /* DCP register layout. */
126 #define MXS_DCP_CTRL				0x00
127 #define MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES	(1 << 23)
128 #define MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING	(1 << 22)
129 
130 #define MXS_DCP_STAT				0x10
131 #define MXS_DCP_STAT_CLR			0x18
132 #define MXS_DCP_STAT_IRQ_MASK			0xf
133 
134 #define MXS_DCP_CHANNELCTRL			0x20
135 #define MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK	0xff
136 
137 #define MXS_DCP_CAPABILITY1			0x40
138 #define MXS_DCP_CAPABILITY1_SHA256		(4 << 16)
139 #define MXS_DCP_CAPABILITY1_SHA1		(1 << 16)
140 #define MXS_DCP_CAPABILITY1_AES128		(1 << 0)
141 
142 #define MXS_DCP_CONTEXT				0x50
143 
144 #define MXS_DCP_CH_N_CMDPTR(n)			(0x100 + ((n) * 0x40))
145 
146 #define MXS_DCP_CH_N_SEMA(n)			(0x110 + ((n) * 0x40))
147 
148 #define MXS_DCP_CH_N_STAT(n)			(0x120 + ((n) * 0x40))
149 #define MXS_DCP_CH_N_STAT_CLR(n)		(0x128 + ((n) * 0x40))
150 
151 /* DMA descriptor bits. */
152 #define MXS_DCP_CONTROL0_HASH_TERM		(1 << 13)
153 #define MXS_DCP_CONTROL0_HASH_INIT		(1 << 12)
154 #define MXS_DCP_CONTROL0_PAYLOAD_KEY		(1 << 11)
155 #define MXS_DCP_CONTROL0_CIPHER_ENCRYPT		(1 << 8)
156 #define MXS_DCP_CONTROL0_CIPHER_INIT		(1 << 9)
157 #define MXS_DCP_CONTROL0_ENABLE_HASH		(1 << 6)
158 #define MXS_DCP_CONTROL0_ENABLE_CIPHER		(1 << 5)
159 #define MXS_DCP_CONTROL0_DECR_SEMAPHORE		(1 << 1)
160 #define MXS_DCP_CONTROL0_INTERRUPT		(1 << 0)
161 
162 #define MXS_DCP_CONTROL1_HASH_SELECT_SHA256	(2 << 16)
163 #define MXS_DCP_CONTROL1_HASH_SELECT_SHA1	(0 << 16)
164 #define MXS_DCP_CONTROL1_CIPHER_MODE_CBC	(1 << 4)
165 #define MXS_DCP_CONTROL1_CIPHER_MODE_ECB	(0 << 4)
166 #define MXS_DCP_CONTROL1_CIPHER_SELECT_AES128	(0 << 0)
167 
168 static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
169 {
170 	struct dcp *sdcp = global_sdcp;
171 	const int chan = actx->chan;
172 	uint32_t stat;
173 	unsigned long ret;
174 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
175 
176 	dma_addr_t desc_phys = dma_map_single(sdcp->dev, desc, sizeof(*desc),
177 					      DMA_TO_DEVICE);
178 
179 	reinit_completion(&sdcp->completion[chan]);
180 
181 	/* Clear status register. */
182 	writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(chan));
183 
184 	/* Load the DMA descriptor. */
185 	writel(desc_phys, sdcp->base + MXS_DCP_CH_N_CMDPTR(chan));
186 
187 	/* Increment the semaphore to start the DMA transfer. */
188 	writel(1, sdcp->base + MXS_DCP_CH_N_SEMA(chan));
189 
190 	ret = wait_for_completion_timeout(&sdcp->completion[chan],
191 					  msecs_to_jiffies(1000));
192 	if (!ret) {
193 		dev_err(sdcp->dev, "Channel %i timeout (DCP_STAT=0x%08x)\n",
194 			chan, readl(sdcp->base + MXS_DCP_STAT));
195 		return -ETIMEDOUT;
196 	}
197 
198 	stat = readl(sdcp->base + MXS_DCP_CH_N_STAT(chan));
199 	if (stat & 0xff) {
200 		dev_err(sdcp->dev, "Channel %i error (CH_STAT=0x%08x)\n",
201 			chan, stat);
202 		return -EINVAL;
203 	}
204 
205 	dma_unmap_single(sdcp->dev, desc_phys, sizeof(*desc), DMA_TO_DEVICE);
206 
207 	return 0;
208 }
209 
210 /*
211  * Encryption (AES128)
212  */
213 static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
214 			   struct skcipher_request *req, int init)
215 {
216 	struct dcp *sdcp = global_sdcp;
217 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
218 	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
219 	int ret;
220 
221 	dma_addr_t key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
222 					     2 * AES_KEYSIZE_128,
223 					     DMA_TO_DEVICE);
224 	dma_addr_t src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
225 					     DCP_BUF_SZ, DMA_TO_DEVICE);
226 	dma_addr_t dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
227 					     DCP_BUF_SZ, DMA_FROM_DEVICE);
228 
229 	if (actx->fill % AES_BLOCK_SIZE) {
230 		dev_err(sdcp->dev, "Invalid block size!\n");
231 		ret = -EINVAL;
232 		goto aes_done_run;
233 	}
234 
235 	/* Fill in the DMA descriptor. */
236 	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
237 		    MXS_DCP_CONTROL0_INTERRUPT |
238 		    MXS_DCP_CONTROL0_ENABLE_CIPHER;
239 
240 	/* Payload contains the key. */
241 	desc->control0 |= MXS_DCP_CONTROL0_PAYLOAD_KEY;
242 
243 	if (rctx->enc)
244 		desc->control0 |= MXS_DCP_CONTROL0_CIPHER_ENCRYPT;
245 	if (init)
246 		desc->control0 |= MXS_DCP_CONTROL0_CIPHER_INIT;
247 
248 	desc->control1 = MXS_DCP_CONTROL1_CIPHER_SELECT_AES128;
249 
250 	if (rctx->ecb)
251 		desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_ECB;
252 	else
253 		desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_CBC;
254 
255 	desc->next_cmd_addr = 0;
256 	desc->source = src_phys;
257 	desc->destination = dst_phys;
258 	desc->size = actx->fill;
259 	desc->payload = key_phys;
260 	desc->status = 0;
261 
262 	ret = mxs_dcp_start_dma(actx);
263 
264 aes_done_run:
265 	dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
266 			 DMA_TO_DEVICE);
267 	dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
268 	dma_unmap_single(sdcp->dev, dst_phys, DCP_BUF_SZ, DMA_FROM_DEVICE);
269 
270 	return ret;
271 }
272 
273 static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
274 {
275 	struct dcp *sdcp = global_sdcp;
276 
277 	struct skcipher_request *req = skcipher_request_cast(arq);
278 	struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
279 	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
280 
281 	struct scatterlist *dst = req->dst;
282 	struct scatterlist *src = req->src;
283 	const int nents = sg_nents(req->src);
284 
285 	const int out_off = DCP_BUF_SZ;
286 	uint8_t *in_buf = sdcp->coh->aes_in_buf;
287 	uint8_t *out_buf = sdcp->coh->aes_out_buf;
288 
289 	uint8_t *out_tmp, *src_buf, *dst_buf = NULL;
290 	uint32_t dst_off = 0;
291 	uint32_t last_out_len = 0;
292 
293 	uint8_t *key = sdcp->coh->aes_key;
294 
295 	int ret = 0;
296 	int split = 0;
297 	unsigned int i, len, clen, rem = 0, tlen = 0;
298 	int init = 0;
299 	bool limit_hit = false;
300 
301 	actx->fill = 0;
302 
303 	/* Copy the key from the temporary location. */
304 	memcpy(key, actx->key, actx->key_len);
305 
306 	if (!rctx->ecb) {
307 		/* Copy the CBC IV just past the key. */
308 		memcpy(key + AES_KEYSIZE_128, req->iv, AES_KEYSIZE_128);
309 		/* CBC needs the INIT set. */
310 		init = 1;
311 	} else {
312 		memset(key + AES_KEYSIZE_128, 0, AES_KEYSIZE_128);
313 	}
314 
315 	for_each_sg(req->src, src, nents, i) {
316 		src_buf = sg_virt(src);
317 		len = sg_dma_len(src);
318 		tlen += len;
319 		limit_hit = tlen > req->cryptlen;
320 
321 		if (limit_hit)
322 			len = req->cryptlen - (tlen - len);
323 
324 		do {
325 			if (actx->fill + len > out_off)
326 				clen = out_off - actx->fill;
327 			else
328 				clen = len;
329 
330 			memcpy(in_buf + actx->fill, src_buf, clen);
331 			len -= clen;
332 			src_buf += clen;
333 			actx->fill += clen;
334 
335 			/*
336 			 * If we filled the buffer or this is the last SG,
337 			 * submit the buffer.
338 			 */
339 			if (actx->fill == out_off || sg_is_last(src) ||
340 				limit_hit) {
341 				ret = mxs_dcp_run_aes(actx, req, init);
342 				if (ret)
343 					return ret;
344 				init = 0;
345 
346 				out_tmp = out_buf;
347 				last_out_len = actx->fill;
348 				while (dst && actx->fill) {
349 					if (!split) {
350 						dst_buf = sg_virt(dst);
351 						dst_off = 0;
352 					}
353 					rem = min(sg_dma_len(dst) - dst_off,
354 						  actx->fill);
355 
356 					memcpy(dst_buf + dst_off, out_tmp, rem);
357 					out_tmp += rem;
358 					dst_off += rem;
359 					actx->fill -= rem;
360 
361 					if (dst_off == sg_dma_len(dst)) {
362 						dst = sg_next(dst);
363 						split = 0;
364 					} else {
365 						split = 1;
366 					}
367 				}
368 			}
369 		} while (len);
370 
371 		if (limit_hit)
372 			break;
373 	}
374 
375 	/* Copy the IV for CBC for chaining */
376 	if (!rctx->ecb) {
377 		if (rctx->enc)
378 			memcpy(req->iv, out_buf+(last_out_len-AES_BLOCK_SIZE),
379 				AES_BLOCK_SIZE);
380 		else
381 			memcpy(req->iv, in_buf+(last_out_len-AES_BLOCK_SIZE),
382 				AES_BLOCK_SIZE);
383 	}
384 
385 	return ret;
386 }
387 
388 static int dcp_chan_thread_aes(void *data)
389 {
390 	struct dcp *sdcp = global_sdcp;
391 	const int chan = DCP_CHAN_CRYPTO;
392 
393 	struct crypto_async_request *backlog;
394 	struct crypto_async_request *arq;
395 
396 	int ret;
397 
398 	while (!kthread_should_stop()) {
399 		set_current_state(TASK_INTERRUPTIBLE);
400 
401 		spin_lock(&sdcp->lock[chan]);
402 		backlog = crypto_get_backlog(&sdcp->queue[chan]);
403 		arq = crypto_dequeue_request(&sdcp->queue[chan]);
404 		spin_unlock(&sdcp->lock[chan]);
405 
406 		if (!backlog && !arq) {
407 			schedule();
408 			continue;
409 		}
410 
411 		set_current_state(TASK_RUNNING);
412 
413 		if (backlog)
414 			backlog->complete(backlog, -EINPROGRESS);
415 
416 		if (arq) {
417 			ret = mxs_dcp_aes_block_crypt(arq);
418 			arq->complete(arq, ret);
419 		}
420 	}
421 
422 	return 0;
423 }
424 
425 static int mxs_dcp_block_fallback(struct skcipher_request *req, int enc)
426 {
427 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
428 	struct dcp_async_ctx *ctx = crypto_skcipher_ctx(tfm);
429 	SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback);
430 	int ret;
431 
432 	skcipher_request_set_sync_tfm(subreq, ctx->fallback);
433 	skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL);
434 	skcipher_request_set_crypt(subreq, req->src, req->dst,
435 				   req->cryptlen, req->iv);
436 
437 	if (enc)
438 		ret = crypto_skcipher_encrypt(subreq);
439 	else
440 		ret = crypto_skcipher_decrypt(subreq);
441 
442 	skcipher_request_zero(subreq);
443 
444 	return ret;
445 }
446 
447 static int mxs_dcp_aes_enqueue(struct skcipher_request *req, int enc, int ecb)
448 {
449 	struct dcp *sdcp = global_sdcp;
450 	struct crypto_async_request *arq = &req->base;
451 	struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
452 	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
453 	int ret;
454 
455 	if (unlikely(actx->key_len != AES_KEYSIZE_128))
456 		return mxs_dcp_block_fallback(req, enc);
457 
458 	rctx->enc = enc;
459 	rctx->ecb = ecb;
460 	actx->chan = DCP_CHAN_CRYPTO;
461 
462 	spin_lock(&sdcp->lock[actx->chan]);
463 	ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
464 	spin_unlock(&sdcp->lock[actx->chan]);
465 
466 	wake_up_process(sdcp->thread[actx->chan]);
467 
468 	return ret;
469 }
470 
471 static int mxs_dcp_aes_ecb_decrypt(struct skcipher_request *req)
472 {
473 	return mxs_dcp_aes_enqueue(req, 0, 1);
474 }
475 
476 static int mxs_dcp_aes_ecb_encrypt(struct skcipher_request *req)
477 {
478 	return mxs_dcp_aes_enqueue(req, 1, 1);
479 }
480 
481 static int mxs_dcp_aes_cbc_decrypt(struct skcipher_request *req)
482 {
483 	return mxs_dcp_aes_enqueue(req, 0, 0);
484 }
485 
486 static int mxs_dcp_aes_cbc_encrypt(struct skcipher_request *req)
487 {
488 	return mxs_dcp_aes_enqueue(req, 1, 0);
489 }
490 
491 static int mxs_dcp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
492 			      unsigned int len)
493 {
494 	struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
495 
496 	/*
497 	 * AES 128 is supposed by the hardware, store key into temporary
498 	 * buffer and exit. We must use the temporary buffer here, since
499 	 * there can still be an operation in progress.
500 	 */
501 	actx->key_len = len;
502 	if (len == AES_KEYSIZE_128) {
503 		memcpy(actx->key, key, len);
504 		return 0;
505 	}
506 
507 	/*
508 	 * If the requested AES key size is not supported by the hardware,
509 	 * but is supported by in-kernel software implementation, we use
510 	 * software fallback.
511 	 */
512 	crypto_sync_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK);
513 	crypto_sync_skcipher_set_flags(actx->fallback,
514 				  tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
515 	return crypto_sync_skcipher_setkey(actx->fallback, key, len);
516 }
517 
518 static int mxs_dcp_aes_fallback_init_tfm(struct crypto_skcipher *tfm)
519 {
520 	const char *name = crypto_tfm_alg_name(crypto_skcipher_tfm(tfm));
521 	struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
522 	struct crypto_sync_skcipher *blk;
523 
524 	blk = crypto_alloc_sync_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
525 	if (IS_ERR(blk))
526 		return PTR_ERR(blk);
527 
528 	actx->fallback = blk;
529 	crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx));
530 	return 0;
531 }
532 
533 static void mxs_dcp_aes_fallback_exit_tfm(struct crypto_skcipher *tfm)
534 {
535 	struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
536 
537 	crypto_free_sync_skcipher(actx->fallback);
538 }
539 
540 /*
541  * Hashing (SHA1/SHA256)
542  */
543 static int mxs_dcp_run_sha(struct ahash_request *req)
544 {
545 	struct dcp *sdcp = global_sdcp;
546 	int ret;
547 
548 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
549 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
550 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
551 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
552 
553 	dma_addr_t digest_phys = 0;
554 	dma_addr_t buf_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_in_buf,
555 					     DCP_BUF_SZ, DMA_TO_DEVICE);
556 
557 	/* Fill in the DMA descriptor. */
558 	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
559 		    MXS_DCP_CONTROL0_INTERRUPT |
560 		    MXS_DCP_CONTROL0_ENABLE_HASH;
561 	if (rctx->init)
562 		desc->control0 |= MXS_DCP_CONTROL0_HASH_INIT;
563 
564 	desc->control1 = actx->alg;
565 	desc->next_cmd_addr = 0;
566 	desc->source = buf_phys;
567 	desc->destination = 0;
568 	desc->size = actx->fill;
569 	desc->payload = 0;
570 	desc->status = 0;
571 
572 	/*
573 	 * Align driver with hw behavior when generating null hashes
574 	 */
575 	if (rctx->init && rctx->fini && desc->size == 0) {
576 		struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
577 		const uint8_t *sha_buf =
578 			(actx->alg == MXS_DCP_CONTROL1_HASH_SELECT_SHA1) ?
579 			sha1_null_hash : sha256_null_hash;
580 		memcpy(sdcp->coh->sha_out_buf, sha_buf, halg->digestsize);
581 		ret = 0;
582 		goto done_run;
583 	}
584 
585 	/* Set HASH_TERM bit for last transfer block. */
586 	if (rctx->fini) {
587 		digest_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_out_buf,
588 					     DCP_SHA_PAY_SZ, DMA_FROM_DEVICE);
589 		desc->control0 |= MXS_DCP_CONTROL0_HASH_TERM;
590 		desc->payload = digest_phys;
591 	}
592 
593 	ret = mxs_dcp_start_dma(actx);
594 
595 	if (rctx->fini)
596 		dma_unmap_single(sdcp->dev, digest_phys, DCP_SHA_PAY_SZ,
597 				 DMA_FROM_DEVICE);
598 
599 done_run:
600 	dma_unmap_single(sdcp->dev, buf_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
601 
602 	return ret;
603 }
604 
605 static int dcp_sha_req_to_buf(struct crypto_async_request *arq)
606 {
607 	struct dcp *sdcp = global_sdcp;
608 
609 	struct ahash_request *req = ahash_request_cast(arq);
610 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
611 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
612 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
613 	struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
614 	const int nents = sg_nents(req->src);
615 
616 	uint8_t *in_buf = sdcp->coh->sha_in_buf;
617 	uint8_t *out_buf = sdcp->coh->sha_out_buf;
618 
619 	uint8_t *src_buf;
620 
621 	struct scatterlist *src;
622 
623 	unsigned int i, len, clen;
624 	int ret;
625 
626 	int fin = rctx->fini;
627 	if (fin)
628 		rctx->fini = 0;
629 
630 	for_each_sg(req->src, src, nents, i) {
631 		src_buf = sg_virt(src);
632 		len = sg_dma_len(src);
633 
634 		do {
635 			if (actx->fill + len > DCP_BUF_SZ)
636 				clen = DCP_BUF_SZ - actx->fill;
637 			else
638 				clen = len;
639 
640 			memcpy(in_buf + actx->fill, src_buf, clen);
641 			len -= clen;
642 			src_buf += clen;
643 			actx->fill += clen;
644 
645 			/*
646 			 * If we filled the buffer and still have some
647 			 * more data, submit the buffer.
648 			 */
649 			if (len && actx->fill == DCP_BUF_SZ) {
650 				ret = mxs_dcp_run_sha(req);
651 				if (ret)
652 					return ret;
653 				actx->fill = 0;
654 				rctx->init = 0;
655 			}
656 		} while (len);
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