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#include <crypto/scatterwalk.h>
24
25#define DCP_MAX_CHANS	4
26#define DCP_BUF_SZ	PAGE_SIZE
27#define DCP_SHA_PAY_SZ  64
28
29#define DCP_ALIGNMENT	64
30
31/*
32 * Null hashes to align with hw behavior on imx6sl and ull
33 * these are flipped for consistency with hw output
34 */
35static const uint8_t sha1_null_hash[] =
36	"\x09\x07\xd8\xaf\x90\x18\x60\x95\xef\xbf"
37	"\x55\x32\x0d\x4b\x6b\x5e\xee\xa3\x39\xda";
38
39static const uint8_t sha256_null_hash[] =
40	"\x55\xb8\x52\x78\x1b\x99\x95\xa4"
41	"\x4c\x93\x9b\x64\xe4\x41\xae\x27"
42	"\x24\xb9\x6f\x99\xc8\xf4\xfb\x9a"
43	"\x14\x1c\xfc\x98\x42\xc4\xb0\xe3";
44
45/* DCP DMA descriptor. */
46struct dcp_dma_desc {
47	uint32_t	next_cmd_addr;
48	uint32_t	control0;
49	uint32_t	control1;
50	uint32_t	source;
51	uint32_t	destination;
52	uint32_t	size;
53	uint32_t	payload;
54	uint32_t	status;
55};
56
57/* Coherent aligned block for bounce buffering. */
58struct dcp_coherent_block {
59	uint8_t			aes_in_buf[DCP_BUF_SZ];
60	uint8_t			aes_out_buf[DCP_BUF_SZ];
61	uint8_t			sha_in_buf[DCP_BUF_SZ];
62	uint8_t			sha_out_buf[DCP_SHA_PAY_SZ];
63
64	uint8_t			aes_key[2 * AES_KEYSIZE_128];
65
66	struct dcp_dma_desc	desc[DCP_MAX_CHANS];
67};
68
69struct dcp {
70	struct device			*dev;
71	void __iomem			*base;
72
73	uint32_t			caps;
74
75	struct dcp_coherent_block	*coh;
76
77	struct completion		completion[DCP_MAX_CHANS];
78	spinlock_t			lock[DCP_MAX_CHANS];
79	struct task_struct		*thread[DCP_MAX_CHANS];
80	struct crypto_queue		queue[DCP_MAX_CHANS];
81	struct clk			*dcp_clk;
82};
83
84enum dcp_chan {
85	DCP_CHAN_HASH_SHA	= 0,
86	DCP_CHAN_CRYPTO		= 2,
87};
88
89struct dcp_async_ctx {
90	/* Common context */
91	enum dcp_chan	chan;
92	uint32_t	fill;
93
94	/* SHA Hash-specific context */
95	struct mutex			mutex;
96	uint32_t			alg;
97	unsigned int			hot:1;
98
99	/* Crypto-specific context */
100	struct crypto_skcipher		*fallback;
101	unsigned int			key_len;
102	uint8_t				key[AES_KEYSIZE_128];
103};
104
105struct dcp_aes_req_ctx {
106	unsigned int	enc:1;
107	unsigned int	ecb:1;
108	struct skcipher_request fallback_req;	// keep at the end
109};
110
111struct dcp_sha_req_ctx {
112	unsigned int	init:1;
113	unsigned int	fini:1;
114};
115
116struct dcp_export_state {
117	struct dcp_sha_req_ctx req_ctx;
118	struct dcp_async_ctx async_ctx;
119};
120
121/*
122 * There can even be only one instance of the MXS DCP due to the
123 * design of Linux Crypto API.
124 */
125static struct dcp *global_sdcp;
126
127/* DCP register layout. */
128#define MXS_DCP_CTRL				0x00
129#define MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES	(1 << 23)
130#define MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING	(1 << 22)
131
132#define MXS_DCP_STAT				0x10
133#define MXS_DCP_STAT_CLR			0x18
134#define MXS_DCP_STAT_IRQ_MASK			0xf
135
136#define MXS_DCP_CHANNELCTRL			0x20
137#define MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK	0xff
138
139#define MXS_DCP_CAPABILITY1			0x40
140#define MXS_DCP_CAPABILITY1_SHA256		(4 << 16)
141#define MXS_DCP_CAPABILITY1_SHA1		(1 << 16)
142#define MXS_DCP_CAPABILITY1_AES128		(1 << 0)
143
144#define MXS_DCP_CONTEXT				0x50
145
146#define MXS_DCP_CH_N_CMDPTR(n)			(0x100 + ((n) * 0x40))
147
148#define MXS_DCP_CH_N_SEMA(n)			(0x110 + ((n) * 0x40))
149
150#define MXS_DCP_CH_N_STAT(n)			(0x120 + ((n) * 0x40))
151#define MXS_DCP_CH_N_STAT_CLR(n)		(0x128 + ((n) * 0x40))
152
153/* DMA descriptor bits. */
154#define MXS_DCP_CONTROL0_HASH_TERM		(1 << 13)
155#define MXS_DCP_CONTROL0_HASH_INIT		(1 << 12)
156#define MXS_DCP_CONTROL0_PAYLOAD_KEY		(1 << 11)
157#define MXS_DCP_CONTROL0_CIPHER_ENCRYPT		(1 << 8)
158#define MXS_DCP_CONTROL0_CIPHER_INIT		(1 << 9)
159#define MXS_DCP_CONTROL0_ENABLE_HASH		(1 << 6)
160#define MXS_DCP_CONTROL0_ENABLE_CIPHER		(1 << 5)
161#define MXS_DCP_CONTROL0_DECR_SEMAPHORE		(1 << 1)
162#define MXS_DCP_CONTROL0_INTERRUPT		(1 << 0)
163
164#define MXS_DCP_CONTROL1_HASH_SELECT_SHA256	(2 << 16)
165#define MXS_DCP_CONTROL1_HASH_SELECT_SHA1	(0 << 16)
166#define MXS_DCP_CONTROL1_CIPHER_MODE_CBC	(1 << 4)
167#define MXS_DCP_CONTROL1_CIPHER_MODE_ECB	(0 << 4)
168#define MXS_DCP_CONTROL1_CIPHER_SELECT_AES128	(0 << 0)
169
170static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
171{
172	int dma_err;
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	dma_addr_t desc_phys = dma_map_single(sdcp->dev, desc, sizeof(*desc),
179					      DMA_TO_DEVICE);
180
181	dma_err = dma_mapping_error(sdcp->dev, desc_phys);
182	if (dma_err)
183		return dma_err;
184
185	reinit_completion(&sdcp->completion[chan]);
186
187	/* Clear status register. */
188	writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(chan));
189
190	/* Load the DMA descriptor. */
191	writel(desc_phys, sdcp->base + MXS_DCP_CH_N_CMDPTR(chan));
192
193	/* Increment the semaphore to start the DMA transfer. */
194	writel(1, sdcp->base + MXS_DCP_CH_N_SEMA(chan));
195
196	ret = wait_for_completion_timeout(&sdcp->completion[chan],
197					  msecs_to_jiffies(1000));
198	if (!ret) {
199		dev_err(sdcp->dev, "Channel %i timeout (DCP_STAT=0x%08x)\n",
200			chan, readl(sdcp->base + MXS_DCP_STAT));
201		return -ETIMEDOUT;
202	}
203
204	stat = readl(sdcp->base + MXS_DCP_CH_N_STAT(chan));
205	if (stat & 0xff) {
206		dev_err(sdcp->dev, "Channel %i error (CH_STAT=0x%08x)\n",
207			chan, stat);
208		return -EINVAL;
209	}
210
211	dma_unmap_single(sdcp->dev, desc_phys, sizeof(*desc), DMA_TO_DEVICE);
212
213	return 0;
214}
215
216/*
217 * Encryption (AES128)
218 */
219static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
220			   struct skcipher_request *req, int init)
221{
222	dma_addr_t key_phys, src_phys, dst_phys;
223	struct dcp *sdcp = global_sdcp;
224	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
225	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
226	int ret;
227
228	key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
229				  2 * AES_KEYSIZE_128, DMA_TO_DEVICE);
230	ret = dma_mapping_error(sdcp->dev, key_phys);
231	if (ret)
232		return ret;
233
234	src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
235				  DCP_BUF_SZ, DMA_TO_DEVICE);
236	ret = dma_mapping_error(sdcp->dev, src_phys);
237	if (ret)
238		goto err_src;
239
240	dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
241				  DCP_BUF_SZ, DMA_FROM_DEVICE);
242	ret = dma_mapping_error(sdcp->dev, dst_phys);
243	if (ret)
244		goto err_dst;
245
246	if (actx->fill % AES_BLOCK_SIZE) {
247		dev_err(sdcp->dev, "Invalid block size!\n");
248		ret = -EINVAL;
249		goto aes_done_run;
250	}
251
252	/* Fill in the DMA descriptor. */
253	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
254		    MXS_DCP_CONTROL0_INTERRUPT |
255		    MXS_DCP_CONTROL0_ENABLE_CIPHER;
256
257	/* Payload contains the key. */
258	desc->control0 |= MXS_DCP_CONTROL0_PAYLOAD_KEY;
259
260	if (rctx->enc)
261		desc->control0 |= MXS_DCP_CONTROL0_CIPHER_ENCRYPT;
262	if (init)
263		desc->control0 |= MXS_DCP_CONTROL0_CIPHER_INIT;
264
265	desc->control1 = MXS_DCP_CONTROL1_CIPHER_SELECT_AES128;
266
267	if (rctx->ecb)
268		desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_ECB;
269	else
270		desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_CBC;
271
272	desc->next_cmd_addr = 0;
273	desc->source = src_phys;
274	desc->destination = dst_phys;
275	desc->size = actx->fill;
276	desc->payload = key_phys;
277	desc->status = 0;
278
279	ret = mxs_dcp_start_dma(actx);
280
281aes_done_run:
282	dma_unmap_single(sdcp->dev, dst_phys, DCP_BUF_SZ, DMA_FROM_DEVICE);
283err_dst:
284	dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
285err_src:
286	dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
287			 DMA_TO_DEVICE);
288
289	return ret;
290}
291
292static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
293{
294	struct dcp *sdcp = global_sdcp;
295
296	struct skcipher_request *req = skcipher_request_cast(arq);
297	struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
298	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
299
300	struct scatterlist *dst = req->dst;
301	struct scatterlist *src = req->src;
302	int dst_nents = sg_nents(dst);
303
304	const int out_off = DCP_BUF_SZ;
305	uint8_t *in_buf = sdcp->coh->aes_in_buf;
306	uint8_t *out_buf = sdcp->coh->aes_out_buf;
307
308	uint32_t dst_off = 0;
309	uint8_t *src_buf = NULL;
310	uint32_t last_out_len = 0;
311
312	uint8_t *key = sdcp->coh->aes_key;
313
314	int ret = 0;
315	unsigned int i, len, clen, tlen = 0;
316	int init = 0;
317	bool limit_hit = false;
318
319	actx->fill = 0;
320
321	/* Copy the key from the temporary location. */
322	memcpy(key, actx->key, actx->key_len);
323
324	if (!rctx->ecb) {
325		/* Copy the CBC IV just past the key. */
326		memcpy(key + AES_KEYSIZE_128, req->iv, AES_KEYSIZE_128);
327		/* CBC needs the INIT set. */
328		init = 1;
329	} else {
330		memset(key + AES_KEYSIZE_128, 0, AES_KEYSIZE_128);
331	}
332
333	for_each_sg(req->src, src, sg_nents(req->src), i) {
334		src_buf = sg_virt(src);
335		len = sg_dma_len(src);
336		tlen += len;
337		limit_hit = tlen > req->cryptlen;
338
339		if (limit_hit)
340			len = req->cryptlen - (tlen - len);
341
342		do {
343			if (actx->fill + len > out_off)
344				clen = out_off - actx->fill;
345			else
346				clen = len;
347
348			memcpy(in_buf + actx->fill, src_buf, clen);
349			len -= clen;
350			src_buf += clen;
351			actx->fill += clen;
352
353			/*
354			 * If we filled the buffer or this is the last SG,
355			 * submit the buffer.
356			 */
357			if (actx->fill == out_off || sg_is_last(src) ||
358			    limit_hit) {
359				ret = mxs_dcp_run_aes(actx, req, init);
360				if (ret)
361					return ret;
362				init = 0;
363
364				sg_pcopy_from_buffer(dst, dst_nents, out_buf,
365						     actx->fill, dst_off);
366				dst_off += actx->fill;
367				last_out_len = actx->fill;
368				actx->fill = 0;
369			}
370		} while (len);
371
372		if (limit_hit)
373			break;
374	}
375
376	/* Copy the IV for CBC for chaining */
377	if (!rctx->ecb) {
378		if (rctx->enc)
379			memcpy(req->iv, out_buf+(last_out_len-AES_BLOCK_SIZE),
380				AES_BLOCK_SIZE);
381		else
382			memcpy(req->iv, in_buf+(last_out_len-AES_BLOCK_SIZE),
383				AES_BLOCK_SIZE);
384	}
385
386	return ret;
387}
388
389static int dcp_chan_thread_aes(void *data)
390{
391	struct dcp *sdcp = global_sdcp;
392	const int chan = DCP_CHAN_CRYPTO;
393
394	struct crypto_async_request *backlog;
395	struct crypto_async_request *arq;
396
397	int ret;
398
399	while (!kthread_should_stop()) {
400		set_current_state(TASK_INTERRUPTIBLE);
401
402		spin_lock(&sdcp->lock[chan]);
403		backlog = crypto_get_backlog(&sdcp->queue[chan]);
404		arq = crypto_dequeue_request(&sdcp->queue[chan]);
405		spin_unlock(&sdcp->lock[chan]);
406
407		if (!backlog && !arq) {
408			schedule();
409			continue;
410		}
411
412		set_current_state(TASK_RUNNING);
413
414		if (backlog)
415			backlog->complete(backlog, -EINPROGRESS);
416
417		if (arq) {
418			ret = mxs_dcp_aes_block_crypt(arq);
419			arq->complete(arq, ret);
420		}
421	}
422
423	return 0;
424}
425
426static int mxs_dcp_block_fallback(struct skcipher_request *req, int enc)
427{
428	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
429	struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
430	struct dcp_async_ctx *ctx = crypto_skcipher_ctx(tfm);
431	int ret;
432
433	skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback);
434	skcipher_request_set_callback(&rctx->fallback_req, req->base.flags,
435				      req->base.complete, req->base.data);
436	skcipher_request_set_crypt(&rctx->fallback_req, req->src, req->dst,
437				   req->cryptlen, req->iv);
438
439	if (enc)
440		ret = crypto_skcipher_encrypt(&rctx->fallback_req);
441	else
442		ret = crypto_skcipher_decrypt(&rctx->fallback_req);
443
444	return ret;
445}
446
447static 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
471static int mxs_dcp_aes_ecb_decrypt(struct skcipher_request *req)
472{
473	return mxs_dcp_aes_enqueue(req, 0, 1);
474}
475
476static int mxs_dcp_aes_ecb_encrypt(struct skcipher_request *req)
477{
478	return mxs_dcp_aes_enqueue(req, 1, 1);
479}
480
481static int mxs_dcp_aes_cbc_decrypt(struct skcipher_request *req)
482{
483	return mxs_dcp_aes_enqueue(req, 0, 0);
484}
485
486static int mxs_dcp_aes_cbc_encrypt(struct skcipher_request *req)
487{
488	return mxs_dcp_aes_enqueue(req, 1, 0);
489}
490
491static 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_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK);
513	crypto_skcipher_set_flags(actx->fallback,
514				  tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
515	return crypto_skcipher_setkey(actx->fallback, key, len);
516}
517
518static 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_skcipher *blk;
523
524	blk = crypto_alloc_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					 crypto_skcipher_reqsize(blk));
531	return 0;
532}
533
534static void mxs_dcp_aes_fallback_exit_tfm(struct crypto_skcipher *tfm)
535{
536	struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
537
538	crypto_free_skcipher(actx->fallback);
539}
540
541/*
542 * Hashing (SHA1/SHA256)
543 */
544static int mxs_dcp_run_sha(struct ahash_request *req)
545{
546	struct dcp *sdcp = global_sdcp;
547	int ret;
548
549	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
550	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
551	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
552	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
553
554	dma_addr_t digest_phys = 0;
555	dma_addr_t buf_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_in_buf,
556					     DCP_BUF_SZ, DMA_TO_DEVICE);
557
558	ret = dma_mapping_error(sdcp->dev, buf_phys);
559	if (ret)
560		return ret;
561
562	/* Fill in the DMA descriptor. */
563	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
564		    MXS_DCP_CONTROL0_INTERRUPT |
565		    MXS_DCP_CONTROL0_ENABLE_HASH;
566	if (rctx->init)
567		desc->control0 |= MXS_DCP_CONTROL0_HASH_INIT;
568
569	desc->control1 = actx->alg;
570	desc->next_cmd_addr = 0;
571	desc->source = buf_phys;
572	desc->destination = 0;
573	desc->size = actx->fill;
574	desc->payload = 0;
575	desc->status = 0;
576
577	/*
578	 * Align driver with hw behavior when generating null hashes
579	 */
580	if (rctx->init && rctx->fini && desc->size == 0) {
581		struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
582		const uint8_t *sha_buf =
583			(actx->alg == MXS_DCP_CONTROL1_HASH_SELECT_SHA1) ?
584			sha1_null_hash : sha256_null_hash;
585		memcpy(sdcp->coh->sha_out_buf, sha_buf, halg->digestsize);
586		ret = 0;
587		goto done_run;
588	}
589
590	/* Set HASH_TERM bit for last transfer block. */
591	if (rctx->fini) {
592		digest_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_out_buf,
593					     DCP_SHA_PAY_SZ, DMA_FROM_DEVICE);
594		ret = dma_mapping_error(sdcp->dev, digest_phys);
595		if (ret)
596			goto done_run;
597
598		desc->control0 |= MXS_DCP_CONTROL0_HASH_TERM;
599		desc->payload = digest_phys;
600	}
601
602	ret = mxs_dcp_start_dma(actx);
603
604	if (rctx->fini)
605		dma_unmap_single(sdcp->dev, digest_phys, DCP_SHA_PAY_SZ,
606				 DMA_FROM_DEVICE);
607
608done_run:
609	dma_unmap_single(sdcp->dev, buf_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
610
611	return ret;
612}
613
614static int dcp_sha_req_to_buf(struct crypto_async_request *arq)
615{
616	struct dcp *sdcp = global_sdcp;
617
618	struct ahash_request *req = ahash_request_cast(arq);
619	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
620	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
621	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
622	struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
623
624	uint8_t *in_buf = sdcp->coh->sha_in_buf;
625	uint8_t *out_buf = sdcp->coh->sha_out_buf;
626
627	struct scatterlist *src;
628
629	unsigned int i, len, clen, oft = 0;
630	int ret;
631
632	int fin = rctx->fini;
633	if (fin)
634		rctx->fini = 0;
635
636	src = req->src;
637	len = req->nbytes;
638
639	while (len) {
640		if (actx->fill + len > DCP_BUF_SZ)
641			clen = DCP_BUF_SZ - actx->fill;
642		else
643			clen = len;
644
645		scatterwalk_map_and_copy(in_buf + actx->fill, src, oft, clen,
646					 0);
647
648		len -= clen;
649		oft += clen;
650		actx->fill += clen;
651
652		/*
653		 * If we filled the buffer and still have some
654		 * more data, submit the buffer.
655		 */
656		if (len && actx->fill == DCP_BUF_SZ) {
657			ret = mxs_dcp_run_sha(req);
658			if (ret)
659				return ret;
660			actx->fill = 0;
661			rctx->init = 0;
662		}
663	}
664
665	if (fin) {
666		rctx->fini = 1;
667
668		/* Submit whatever is left. */
669		if (!req->result)
670			return -EINVAL;
671
672		ret = mxs_dcp_run_sha(req);
673		if (ret)
674			return ret;
675
676		actx->fill = 0;
677
678		/* For some reason the result is flipped */
679		for (i = 0; i < halg->digestsize; i++)
680			req->result[i] = out_buf[halg->digestsize - i - 1];
681	}
682
683	return 0;
684}
685
686static int dcp_chan_thread_sha(void *data)
687{
688	struct dcp *sdcp = global_sdcp;
689	const int chan = DCP_CHAN_HASH_SHA;
690
691	struct crypto_async_request *backlog;
692	struct crypto_async_request *arq;
693	int ret;
694
695	while (!kthread_should_stop()) {
696		set_current_state(TASK_INTERRUPTIBLE);
697
698		spin_lock(&sdcp->lock[chan]);
699		backlog = crypto_get_backlog(&sdcp->queue[chan]);
700		arq = crypto_dequeue_request(&sdcp->queue[chan]);
701		spin_unlock(&sdcp->lock[chan]);
702
703		if (!backlog && !arq) {
704			schedule();
705			continue;
706		}
707
708		set_current_state(TASK_RUNNING);
709
710		if (backlog)
711			backlog->complete(backlog, -EINPROGRESS);
712
713		if (arq) {
714			ret = dcp_sha_req_to_buf(arq);
715			arq->complete(arq, ret);
716		}
717	}
718
719	return 0;
720}
721
722static int dcp_sha_init(struct ahash_request *req)
723{
724	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
725	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
726
727	struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
728
729	/*
730	 * Start hashing session. The code below only inits the
731	 * hashing session context, nothing more.
732	 */
733	memset(actx, 0, sizeof(*actx));
734
735	if (strcmp(halg->base.cra_name, "sha1") == 0)
736		actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA1;
737	else
738		actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA256;
739
740	actx->fill = 0;
741	actx->hot = 0;
742	actx->chan = DCP_CHAN_HASH_SHA;
743
744	mutex_init(&actx->mutex);
745
746	return 0;
747}
748
749static int dcp_sha_update_fx(struct ahash_request *req, int fini)
750{
751	struct dcp *sdcp = global_sdcp;
752
753	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
754	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
755	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
756
757	int ret;
758
759	/*
760	 * Ignore requests that have no data in them and are not
761	 * the trailing requests in the stream of requests.
762	 */
763	if (!req->nbytes && !fini)
764		return 0;
765
766	mutex_lock(&actx->mutex);
767
768	rctx->fini = fini;
769
770	if (!actx->hot) {
771		actx->hot = 1;
772		rctx->init = 1;
773	}
774
775	spin_lock(&sdcp->lock[actx->chan]);
776	ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
777	spin_unlock(&sdcp->lock[actx->chan]);
778
779	wake_up_process(sdcp->thread[actx->chan]);
780	mutex_unlock(&actx->mutex);
781
782	return ret;
783}
784
785static int dcp_sha_update(struct ahash_request *req)
786{
787	return dcp_sha_update_fx(req, 0);
788}
789
790static int dcp_sha_final(struct ahash_request *req)
791{
792	ahash_request_set_crypt(req, NULL, req->result, 0);
793	req->nbytes = 0;
794	return dcp_sha_update_fx(req, 1);
795}
796
797static int dcp_sha_finup(struct ahash_request *req)
798{
799	return dcp_sha_update_fx(req, 1);
800}
801
802static int dcp_sha_digest(struct ahash_request *req)
803{
804	int ret;
805
806	ret = dcp_sha_init(req);
807	if (ret)
808		return ret;
809
810	return dcp_sha_finup(req);
811}
812
813static int dcp_sha_import(struct ahash_request *req, const void *in)
814{
815	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
816	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
817	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
818	const struct dcp_export_state *export = in;
819
820	memset(rctx, 0, sizeof(struct dcp_sha_req_ctx));
821	memset(actx, 0, sizeof(struct dcp_async_ctx));
822	memcpy(rctx, &export->req_ctx, sizeof(struct dcp_sha_req_ctx));
823	memcpy(actx, &export->async_ctx, sizeof(struct dcp_async_ctx));
824
825	return 0;
826}
827
828static int dcp_sha_export(struct ahash_request *req, void *out)
829{
830	struct dcp_sha_req_ctx *rctx_state = ahash_request_ctx(req);
831	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
832	struct dcp_async_ctx *actx_state = crypto_ahash_ctx(tfm);
833	struct dcp_export_state *export = out;
834
835	memcpy(&export->req_ctx, rctx_state, sizeof(struct dcp_sha_req_ctx));
836	memcpy(&export->async_ctx, actx_state, sizeof(struct dcp_async_ctx));
837
838	return 0;
839}
840
841static int dcp_sha_cra_init(struct crypto_tfm *tfm)
842{
843	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
844				 sizeof(struct dcp_sha_req_ctx));
845	return 0;
846}
847
848static void dcp_sha_cra_exit(struct crypto_tfm *tfm)
849{
850}
851
852/* AES 128 ECB and AES 128 CBC */
853static struct skcipher_alg dcp_aes_algs[] = {
854	{
855		.base.cra_name		= "ecb(aes)",
856		.base.cra_driver_name	= "ecb-aes-dcp",
857		.base.cra_priority	= 400,
858		.base.cra_alignmask	= 15,
859		.base.cra_flags		= CRYPTO_ALG_ASYNC |
860					  CRYPTO_ALG_NEED_FALLBACK,
861		.base.cra_blocksize	= AES_BLOCK_SIZE,
862		.base.cra_ctxsize	= sizeof(struct dcp_async_ctx),
863		.base.cra_module	= THIS_MODULE,
864
865		.min_keysize		= AES_MIN_KEY_SIZE,
866		.max_keysize		= AES_MAX_KEY_SIZE,
867		.setkey			= mxs_dcp_aes_setkey,
868		.encrypt		= mxs_dcp_aes_ecb_encrypt,
869		.decrypt		= mxs_dcp_aes_ecb_decrypt,
870		.init			= mxs_dcp_aes_fallback_init_tfm,
871		.exit			= mxs_dcp_aes_fallback_exit_tfm,
872	}, {
873		.base.cra_name		= "cbc(aes)",
874		.base.cra_driver_name	= "cbc-aes-dcp",
875		.base.cra_priority	= 400,
876		.base.cra_alignmask	= 15,
877		.base.cra_flags		= CRYPTO_ALG_ASYNC |
878					  CRYPTO_ALG_NEED_FALLBACK,
879		.base.cra_blocksize	= AES_BLOCK_SIZE,
880		.base.cra_ctxsize	= sizeof(struct dcp_async_ctx),
881		.base.cra_module	= THIS_MODULE,
882
883		.min_keysize		= AES_MIN_KEY_SIZE,
884		.max_keysize		= AES_MAX_KEY_SIZE,
885		.setkey			= mxs_dcp_aes_setkey,
886		.encrypt		= mxs_dcp_aes_cbc_encrypt,
887		.decrypt		= mxs_dcp_aes_cbc_decrypt,
888		.ivsize			= AES_BLOCK_SIZE,
889		.init			= mxs_dcp_aes_fallback_init_tfm,
890		.exit			= mxs_dcp_aes_fallback_exit_tfm,
891	},
892};
893
894/* SHA1 */
895static struct ahash_alg dcp_sha1_alg = {
896	.init	= dcp_sha_init,
897	.update	= dcp_sha_update,
898	.final	= dcp_sha_final,
899	.finup	= dcp_sha_finup,
900	.digest	= dcp_sha_digest,
901	.import = dcp_sha_import,
902	.export = dcp_sha_export,
903	.halg	= {
904		.digestsize	= SHA1_DIGEST_SIZE,
905		.statesize	= sizeof(struct dcp_export_state),
906		.base		= {
907			.cra_name		= "sha1",
908			.cra_driver_name	= "sha1-dcp",
909			.cra_priority		= 400,
910			.cra_alignmask		= 63,
911			.cra_flags		= CRYPTO_ALG_ASYNC,
912			.cra_blocksize		= SHA1_BLOCK_SIZE,
913			.cra_ctxsize		= sizeof(struct dcp_async_ctx),
914			.cra_module		= THIS_MODULE,
915			.cra_init		= dcp_sha_cra_init,
916			.cra_exit		= dcp_sha_cra_exit,
917		},
918	},
919};
920
921/* SHA256 */
922static struct ahash_alg dcp_sha256_alg = {
923	.init	= dcp_sha_init,
924	.update	= dcp_sha_update,
925	.final	= dcp_sha_final,
926	.finup	= dcp_sha_finup,
927	.digest	= dcp_sha_digest,
928	.import = dcp_sha_import,
929	.export = dcp_sha_export,
930	.halg	= {
931		.digestsize	= SHA256_DIGEST_SIZE,
932		.statesize	= sizeof(struct dcp_export_state),
933		.base		= {
934			.cra_name		= "sha256",
935			.cra_driver_name	= "sha256-dcp",
936			.cra_priority		= 400,
937			.cra_alignmask		= 63,
938			.cra_flags		= CRYPTO_ALG_ASYNC,
939			.cra_blocksize		= SHA256_BLOCK_SIZE,
940			.cra_ctxsize		= sizeof(struct dcp_async_ctx),
941			.cra_module		= THIS_MODULE,
942			.cra_init		= dcp_sha_cra_init,
943			.cra_exit		= dcp_sha_cra_exit,
944		},
945	},
946};
947
948static irqreturn_t mxs_dcp_irq(int irq, void *context)
949{
950	struct dcp *sdcp = context;
951	uint32_t stat;
952	int i;
953
954	stat = readl(sdcp->base + MXS_DCP_STAT);
955	stat &= MXS_DCP_STAT_IRQ_MASK;
956	if (!stat)
957		return IRQ_NONE;
958
959	/* Clear the interrupts. */
960	writel(stat, sdcp->base + MXS_DCP_STAT_CLR);
961
962	/* Complete the DMA requests that finished. */
963	for (i = 0; i < DCP_MAX_CHANS; i++)
964		if (stat & (1 << i))
965			complete(&sdcp->completion[i]);
966
967	return IRQ_HANDLED;
968}
969
970static int mxs_dcp_probe(struct platform_device *pdev)
971{
972	struct device *dev = &pdev->dev;
973	struct dcp *sdcp = NULL;
974	int i, ret;
975	int dcp_vmi_irq, dcp_irq;
976
977	if (global_sdcp) {
978		dev_err(dev, "Only one DCP instance allowed!\n");
979		return -ENODEV;
980	}
981
982	dcp_vmi_irq = platform_get_irq(pdev, 0);
983	if (dcp_vmi_irq < 0)
984		return dcp_vmi_irq;
985
986	dcp_irq = platform_get_irq(pdev, 1);
987	if (dcp_irq < 0)
988		return dcp_irq;
989
990	sdcp = devm_kzalloc(dev, sizeof(*sdcp), GFP_KERNEL);
991	if (!sdcp)
992		return -ENOMEM;
993
994	sdcp->dev = dev;
995	sdcp->base = devm_platform_ioremap_resource(pdev, 0);
996	if (IS_ERR(sdcp->base))
997		return PTR_ERR(sdcp->base);
998
999
1000	ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
1001			       "dcp-vmi-irq", sdcp);
1002	if (ret) {
1003		dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
1004		return ret;
1005	}
1006
1007	ret = devm_request_irq(dev, dcp_irq, mxs_dcp_irq, 0,
1008			       "dcp-irq", sdcp);
1009	if (ret) {
1010		dev_err(dev, "Failed to claim DCP IRQ!\n");
1011		return ret;
1012	}
1013
1014	/* Allocate coherent helper block. */
1015	sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh) + DCP_ALIGNMENT,
1016				   GFP_KERNEL);
1017	if (!sdcp->coh)
1018		return -ENOMEM;
1019
1020	/* Re-align the structure so it fits the DCP constraints. */
1021	sdcp->coh = PTR_ALIGN(sdcp->coh, DCP_ALIGNMENT);
1022
1023	/* DCP clock is optional, only used on some SOCs */
1024	sdcp->dcp_clk = devm_clk_get(dev, "dcp");
1025	if (IS_ERR(sdcp->dcp_clk)) {
1026		if (sdcp->dcp_clk != ERR_PTR(-ENOENT))
1027			return PTR_ERR(sdcp->dcp_clk);
1028		sdcp->dcp_clk = NULL;
1029	}
1030	ret = clk_prepare_enable(sdcp->dcp_clk);
1031	if (ret)
1032		return ret;
1033
1034	/* Restart the DCP block. */
1035	ret = stmp_reset_block(sdcp->base);
1036	if (ret) {
1037		dev_err(dev, "Failed reset\n");
1038		goto err_disable_unprepare_clk;
1039	}
1040
1041	/* Initialize control register. */
1042	writel(MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES |
1043	       MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING | 0xf,
1044	       sdcp->base + MXS_DCP_CTRL);
1045
1046	/* Enable all DCP DMA channels. */
1047	writel(MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK,
1048	       sdcp->base + MXS_DCP_CHANNELCTRL);
1049
1050	/*
1051	 * We do not enable context switching. Give the context buffer a
1052	 * pointer to an illegal address so if context switching is
1053	 * inadvertantly enabled, the DCP will return an error instead of
1054	 * trashing good memory. The DCP DMA cannot access ROM, so any ROM
1055	 * address will do.
1056	 */
1057	writel(0xffff0000, sdcp->base + MXS_DCP_CONTEXT);
1058	for (i = 0; i < DCP_MAX_CHANS; i++)
1059		writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(i));
1060	writel(0xffffffff, sdcp->base + MXS_DCP_STAT_CLR);
1061
1062	global_sdcp = sdcp;
1063
1064	platform_set_drvdata(pdev, sdcp);
1065
1066	for (i = 0; i < DCP_MAX_CHANS; i++) {
1067		spin_lock_init(&sdcp->lock[i]);
1068		init_completion(&sdcp->completion[i]);
1069		crypto_init_queue(&sdcp->queue[i], 50);
1070	}
1071
1072	/* Create the SHA and AES handler threads. */
1073	sdcp->thread[DCP_CHAN_HASH_SHA] = kthread_run(dcp_chan_thread_sha,
1074						      NULL, "mxs_dcp_chan/sha");
1075	if (IS_ERR(sdcp->thread[DCP_CHAN_HASH_SHA])) {
1076		dev_err(dev, "Error starting SHA thread!\n");
1077		ret = PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
1078		goto err_disable_unprepare_clk;
1079	}
1080
1081	sdcp->thread[DCP_CHAN_CRYPTO] = kthread_run(dcp_chan_thread_aes,
1082						    NULL, "mxs_dcp_chan/aes");
1083	if (IS_ERR(sdcp->thread[DCP_CHAN_CRYPTO])) {
1084		dev_err(dev, "Error starting SHA thread!\n");
1085		ret = PTR_ERR(sdcp->thread[DCP_CHAN_CRYPTO]);
1086		goto err_destroy_sha_thread;
1087	}
1088
1089	/* Register the various crypto algorithms. */
1090	sdcp->caps = readl(sdcp->base + MXS_DCP_CAPABILITY1);
1091
1092	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128) {
1093		ret = crypto_register_skciphers(dcp_aes_algs,
1094						ARRAY_SIZE(dcp_aes_algs));
1095		if (ret) {
1096			/* Failed to register algorithm. */
1097			dev_err(dev, "Failed to register AES crypto!\n");
1098			goto err_destroy_aes_thread;
1099		}
1100	}
1101
1102	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1) {
1103		ret = crypto_register_ahash(&dcp_sha1_alg);
1104		if (ret) {
1105			dev_err(dev, "Failed to register %s hash!\n",
1106				dcp_sha1_alg.halg.base.cra_name);
1107			goto err_unregister_aes;
1108		}
1109	}
1110
1111	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256) {
1112		ret = crypto_register_ahash(&dcp_sha256_alg);
1113		if (ret) {
1114			dev_err(dev, "Failed to register %s hash!\n",
1115				dcp_sha256_alg.halg.base.cra_name);
1116			goto err_unregister_sha1;
1117		}
1118	}
1119
1120	return 0;
1121
1122err_unregister_sha1:
1123	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1124		crypto_unregister_ahash(&dcp_sha1_alg);
1125
1126err_unregister_aes:
1127	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1128		crypto_unregister_skciphers(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1129
1130err_destroy_aes_thread:
1131	kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1132
1133err_destroy_sha_thread:
1134	kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1135
1136err_disable_unprepare_clk:
1137	clk_disable_unprepare(sdcp->dcp_clk);
1138
1139	return ret;
1140}
1141
1142static int mxs_dcp_remove(struct platform_device *pdev)
1143{
1144	struct dcp *sdcp = platform_get_drvdata(pdev);
1145
1146	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256)
1147		crypto_unregister_ahash(&dcp_sha256_alg);
1148
1149	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1150		crypto_unregister_ahash(&dcp_sha1_alg);
1151
1152	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1153		crypto_unregister_skciphers(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1154
1155	kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1156	kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1157
1158	clk_disable_unprepare(sdcp->dcp_clk);
1159
1160	platform_set_drvdata(pdev, NULL);
1161
1162	global_sdcp = NULL;
1163
1164	return 0;
1165}
1166
1167static const struct of_device_id mxs_dcp_dt_ids[] = {
1168	{ .compatible = "fsl,imx23-dcp", .data = NULL, },
1169	{ .compatible = "fsl,imx28-dcp", .data = NULL, },
1170	{ /* sentinel */ }
1171};
1172
1173MODULE_DEVICE_TABLE(of, mxs_dcp_dt_ids);
1174
1175static struct platform_driver mxs_dcp_driver = {
1176	.probe	= mxs_dcp_probe,
1177	.remove	= mxs_dcp_remove,
1178	.driver	= {
1179		.name		= "mxs-dcp",
1180		.of_match_table	= mxs_dcp_dt_ids,
1181	},
1182};
1183
1184module_platform_driver(mxs_dcp_driver);
1185
1186MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
1187MODULE_DESCRIPTION("Freescale MXS DCP Driver");
1188MODULE_LICENSE("GPL");
1189MODULE_ALIAS("platform:mxs-dcp");
1190