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