1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * sun8i-ss-hash.c - hardware cryptographic offloader for
4  * Allwinner A80/A83T SoC
5  *
6  * Copyright (C) 2015-2020 Corentin Labbe <clabbe@baylibre.com>
7  *
8  * This file add support for MD5 and SHA1/SHA224/SHA256.
9  *
10  * You could find the datasheet in Documentation/arch/arm/sunxi.rst
11  */
12 
13 #include <crypto/hmac.h>
14 #include <crypto/internal/hash.h>
15 #include <crypto/md5.h>
16 #include <crypto/scatterwalk.h>
17 #include <crypto/sha1.h>
18 #include <crypto/sha2.h>
19 #include <linux/bottom_half.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/err.h>
22 #include <linux/kernel.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/scatterlist.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27 #include "sun8i-ss.h"
28 
29 static int sun8i_ss_hashkey(struct sun8i_ss_hash_tfm_ctx *tfmctx, const u8 *key,
30 			    unsigned int keylen)
31 {
32 	struct crypto_shash *xtfm;
33 	struct shash_desc *sdesc;
34 	size_t len;
35 	int ret = 0;
36 
37 	xtfm = crypto_alloc_shash("sha1", 0, CRYPTO_ALG_NEED_FALLBACK);
38 	if (IS_ERR(xtfm))
39 		return PTR_ERR(xtfm);
40 
41 	len = sizeof(*sdesc) + crypto_shash_descsize(xtfm);
42 	sdesc = kmalloc(len, GFP_KERNEL);
43 	if (!sdesc) {
44 		ret = -ENOMEM;
45 		goto err_hashkey_sdesc;
46 	}
47 	sdesc->tfm = xtfm;
48 
49 	ret = crypto_shash_init(sdesc);
50 	if (ret) {
51 		dev_err(tfmctx->ss->dev, "shash init error ret=%d\n", ret);
52 		goto err_hashkey;
53 	}
54 	ret = crypto_shash_finup(sdesc, key, keylen, tfmctx->key);
55 	if (ret)
56 		dev_err(tfmctx->ss->dev, "shash finup error\n");
57 err_hashkey:
58 	kfree(sdesc);
59 err_hashkey_sdesc:
60 	crypto_free_shash(xtfm);
61 	return ret;
62 }
63 
64 int sun8i_ss_hmac_setkey(struct crypto_ahash *ahash, const u8 *key,
65 			 unsigned int keylen)
66 {
67 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(ahash);
68 	int digestsize, i;
69 	int bs = crypto_ahash_blocksize(ahash);
70 	int ret;
71 
72 	digestsize = crypto_ahash_digestsize(ahash);
73 
74 	if (keylen > bs) {
75 		ret = sun8i_ss_hashkey(tfmctx, key, keylen);
76 		if (ret)
77 			return ret;
78 		tfmctx->keylen = digestsize;
79 	} else {
80 		tfmctx->keylen = keylen;
81 		memcpy(tfmctx->key, key, keylen);
82 	}
83 
84 	tfmctx->ipad = kzalloc(bs, GFP_KERNEL);
85 	if (!tfmctx->ipad)
86 		return -ENOMEM;
87 	tfmctx->opad = kzalloc(bs, GFP_KERNEL);
88 	if (!tfmctx->opad) {
89 		ret = -ENOMEM;
90 		goto err_opad;
91 	}
92 
93 	memset(tfmctx->key + tfmctx->keylen, 0, bs - tfmctx->keylen);
94 	memcpy(tfmctx->ipad, tfmctx->key, tfmctx->keylen);
95 	memcpy(tfmctx->opad, tfmctx->key, tfmctx->keylen);
96 	for (i = 0; i < bs; i++) {
97 		tfmctx->ipad[i] ^= HMAC_IPAD_VALUE;
98 		tfmctx->opad[i] ^= HMAC_OPAD_VALUE;
99 	}
100 
101 	ret = crypto_ahash_setkey(tfmctx->fallback_tfm, key, keylen);
102 	if (!ret)
103 		return 0;
104 
105 	memzero_explicit(tfmctx->key, keylen);
106 	kfree_sensitive(tfmctx->opad);
107 err_opad:
108 	kfree_sensitive(tfmctx->ipad);
109 	return ret;
110 }
111 
112 int sun8i_ss_hash_init_tfm(struct crypto_ahash *tfm)
113 {
114 	struct sun8i_ss_hash_tfm_ctx *op = crypto_ahash_ctx(tfm);
115 	struct ahash_alg *alg = crypto_ahash_alg(tfm);
116 	struct sun8i_ss_alg_template *algt;
117 	int err;
118 
119 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash.base);
120 	op->ss = algt->ss;
121 
122 	/* FALLBACK */
123 	op->fallback_tfm = crypto_alloc_ahash(crypto_ahash_alg_name(tfm), 0,
124 					      CRYPTO_ALG_NEED_FALLBACK);
125 	if (IS_ERR(op->fallback_tfm)) {
126 		dev_err(algt->ss->dev, "Fallback driver could no be loaded\n");
127 		return PTR_ERR(op->fallback_tfm);
128 	}
129 
130 	crypto_ahash_set_statesize(tfm,
131 				   crypto_ahash_statesize(op->fallback_tfm));
132 
133 	crypto_ahash_set_reqsize(tfm,
134 				 sizeof(struct sun8i_ss_hash_reqctx) +
135 				 crypto_ahash_reqsize(op->fallback_tfm));
136 
137 	memcpy(algt->fbname, crypto_ahash_driver_name(op->fallback_tfm),
138 	       CRYPTO_MAX_ALG_NAME);
139 
140 	err = pm_runtime_get_sync(op->ss->dev);
141 	if (err < 0)
142 		goto error_pm;
143 	return 0;
144 error_pm:
145 	pm_runtime_put_noidle(op->ss->dev);
146 	crypto_free_ahash(op->fallback_tfm);
147 	return err;
148 }
149 
150 void sun8i_ss_hash_exit_tfm(struct crypto_ahash *tfm)
151 {
152 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
153 
154 	kfree_sensitive(tfmctx->ipad);
155 	kfree_sensitive(tfmctx->opad);
156 
157 	crypto_free_ahash(tfmctx->fallback_tfm);
158 	pm_runtime_put_sync_suspend(tfmctx->ss->dev);
159 }
160 
161 int sun8i_ss_hash_init(struct ahash_request *areq)
162 {
163 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
164 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
165 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
166 
167 	memset(rctx, 0, sizeof(struct sun8i_ss_hash_reqctx));
168 
169 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
170 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
171 
172 	return crypto_ahash_init(&rctx->fallback_req);
173 }
174 
175 int sun8i_ss_hash_export(struct ahash_request *areq, void *out)
176 {
177 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
178 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
179 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
180 
181 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
182 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
183 
184 	return crypto_ahash_export(&rctx->fallback_req, out);
185 }
186 
187 int sun8i_ss_hash_import(struct ahash_request *areq, const void *in)
188 {
189 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
190 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
191 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
192 
193 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
194 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
195 
196 	return crypto_ahash_import(&rctx->fallback_req, in);
197 }
198 
199 int sun8i_ss_hash_final(struct ahash_request *areq)
200 {
201 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
202 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
203 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
204 
205 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
206 	rctx->fallback_req.base.flags = areq->base.flags &
207 					CRYPTO_TFM_REQ_MAY_SLEEP;
208 	rctx->fallback_req.result = areq->result;
209 
210 	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG)) {
211 		struct ahash_alg *alg = crypto_ahash_alg(tfm);
212 		struct sun8i_ss_alg_template *algt __maybe_unused;
213 
214 		algt = container_of(alg, struct sun8i_ss_alg_template,
215 				    alg.hash.base);
216 
217 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
218 		algt->stat_fb++;
219 #endif
220 	}
221 
222 	return crypto_ahash_final(&rctx->fallback_req);
223 }
224 
225 int sun8i_ss_hash_update(struct ahash_request *areq)
226 {
227 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
228 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
229 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
230 
231 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
232 	rctx->fallback_req.base.flags = areq->base.flags &
233 					CRYPTO_TFM_REQ_MAY_SLEEP;
234 	rctx->fallback_req.nbytes = areq->nbytes;
235 	rctx->fallback_req.src = areq->src;
236 
237 	return crypto_ahash_update(&rctx->fallback_req);
238 }
239 
240 int sun8i_ss_hash_finup(struct ahash_request *areq)
241 {
242 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
243 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
244 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
245 
246 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
247 	rctx->fallback_req.base.flags = areq->base.flags &
248 					CRYPTO_TFM_REQ_MAY_SLEEP;
249 
250 	rctx->fallback_req.nbytes = areq->nbytes;
251 	rctx->fallback_req.src = areq->src;
252 	rctx->fallback_req.result = areq->result;
253 
254 	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG)) {
255 		struct ahash_alg *alg = crypto_ahash_alg(tfm);
256 		struct sun8i_ss_alg_template *algt __maybe_unused;
257 
258 		algt = container_of(alg, struct sun8i_ss_alg_template,
259 				    alg.hash.base);
260 
261 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
262 		algt->stat_fb++;
263 #endif
264 	}
265 
266 	return crypto_ahash_finup(&rctx->fallback_req);
267 }
268 
269 static int sun8i_ss_hash_digest_fb(struct ahash_request *areq)
270 {
271 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
272 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
273 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
274 
275 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
276 	rctx->fallback_req.base.flags = areq->base.flags &
277 					CRYPTO_TFM_REQ_MAY_SLEEP;
278 
279 	rctx->fallback_req.nbytes = areq->nbytes;
280 	rctx->fallback_req.src = areq->src;
281 	rctx->fallback_req.result = areq->result;
282 
283 	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG)) {
284 		struct ahash_alg *alg = crypto_ahash_alg(tfm);
285 		struct sun8i_ss_alg_template *algt __maybe_unused;
286 
287 		algt = container_of(alg, struct sun8i_ss_alg_template,
288 				    alg.hash.base);
289 
290 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
291 		algt->stat_fb++;
292 #endif
293 	}
294 
295 	return crypto_ahash_digest(&rctx->fallback_req);
296 }
297 
298 static int sun8i_ss_run_hash_task(struct sun8i_ss_dev *ss,
299 				  struct sun8i_ss_hash_reqctx *rctx,
300 				  const char *name)
301 {
302 	int flow = rctx->flow;
303 	u32 v = SS_START;
304 	int i;
305 
306 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
307 	ss->flows[flow].stat_req++;
308 #endif
309 
310 	/* choose between stream0/stream1 */
311 	if (flow)
312 		v |= SS_FLOW1;
313 	else
314 		v |= SS_FLOW0;
315 
316 	v |= rctx->method;
317 
318 	for (i = 0; i < MAX_SG; i++) {
319 		if (!rctx->t_dst[i].addr)
320 			break;
321 
322 		mutex_lock(&ss->mlock);
323 		if (i > 0) {
324 			v |= BIT(17);
325 			writel(rctx->t_dst[i - 1].addr, ss->base + SS_KEY_ADR_REG);
326 			writel(rctx->t_dst[i - 1].addr, ss->base + SS_IV_ADR_REG);
327 		}
328 
329 		dev_dbg(ss->dev,
330 			"Processing SG %d on flow %d %s ctl=%x %d to %d method=%x src=%x dst=%x\n",
331 			i, flow, name, v,
332 			rctx->t_src[i].len, rctx->t_dst[i].len,
333 			rctx->method, rctx->t_src[i].addr, rctx->t_dst[i].addr);
334 
335 		writel(rctx->t_src[i].addr, ss->base + SS_SRC_ADR_REG);
336 		writel(rctx->t_dst[i].addr, ss->base + SS_DST_ADR_REG);
337 		writel(rctx->t_src[i].len, ss->base + SS_LEN_ADR_REG);
338 		writel(BIT(0) | BIT(1), ss->base + SS_INT_CTL_REG);
339 
340 		reinit_completion(&ss->flows[flow].complete);
341 		ss->flows[flow].status = 0;
342 		wmb();
343 
344 		writel(v, ss->base + SS_CTL_REG);
345 		mutex_unlock(&ss->mlock);
346 		wait_for_completion_interruptible_timeout(&ss->flows[flow].complete,
347 							  msecs_to_jiffies(2000));
348 		if (ss->flows[flow].status == 0) {
349 			dev_err(ss->dev, "DMA timeout for %s\n", name);
350 			return -EFAULT;
351 		}
352 	}
353 
354 	return 0;
355 }
356 
357 static bool sun8i_ss_hash_need_fallback(struct ahash_request *areq)
358 {
359 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
360 	struct ahash_alg *alg = crypto_ahash_alg(tfm);
361 	struct sun8i_ss_alg_template *algt;
362 	struct scatterlist *sg;
363 
364 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash.base);
365 
366 	if (areq->nbytes == 0) {
367 		algt->stat_fb_len++;
368 		return true;
369 	}
370 
371 	if (areq->nbytes >= MAX_PAD_SIZE - 64) {
372 		algt->stat_fb_len++;
373 		return true;
374 	}
375 
376 	/* we need to reserve one SG for the padding one */
377 	if (sg_nents(areq->src) > MAX_SG - 1) {
378 		algt->stat_fb_sgnum++;
379 		return true;
380 	}
381 
382 	sg = areq->src;
383 	while (sg) {
384 		/* SS can operate hash only on full block size
385 		 * since SS support only MD5,sha1,sha224 and sha256, blocksize
386 		 * is always 64
387 		 */
388 		/* Only the last block could be bounced to the pad buffer */
389 		if (sg->length % 64 && sg_next(sg)) {
390 			algt->stat_fb_sglen++;
391 			return true;
392 		}
393 		if (!IS_ALIGNED(sg->offset, sizeof(u32))) {
394 			algt->stat_fb_align++;
395 			return true;
396 		}
397 		if (sg->length % 4) {
398 			algt->stat_fb_sglen++;
399 			return true;
400 		}
401 		sg = sg_next(sg);
402 	}
403 	return false;
404 }
405 
406 int sun8i_ss_hash_digest(struct ahash_request *areq)
407 {
408 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
409 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
410 	struct ahash_alg *alg = crypto_ahash_alg(tfm);
411 	struct sun8i_ss_alg_template *algt;
412 	struct sun8i_ss_dev *ss;
413 	struct crypto_engine *engine;
414 	int e;
415 
416 	if (sun8i_ss_hash_need_fallback(areq))
417 		return sun8i_ss_hash_digest_fb(areq);
418 
419 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash.base);
420 	ss = algt->ss;
421 
422 	e = sun8i_ss_get_engine_number(ss);
423 	rctx->flow = e;
424 	engine = ss->flows[e].engine;
425 
426 	return crypto_transfer_hash_request_to_engine(engine, areq);
427 }
428 
429 static u64 hash_pad(__le32 *buf, unsigned int bufsize, u64 padi, u64 byte_count, bool le, int bs)
430 {
431 	u64 fill, min_fill, j, k;
432 	__be64 *bebits;
433 	__le64 *lebits;
434 
435 	j = padi;
436 	buf[j++] = cpu_to_le32(0x80);
437 
438 	if (bs == 64) {
439 		fill = 64 - (byte_count % 64);
440 		min_fill = 2 * sizeof(u32) + sizeof(u32);
441 	} else {
442 		fill = 128 - (byte_count % 128);
443 		min_fill = 4 * sizeof(u32) + sizeof(u32);
444 	}
445 
446 	if (fill < min_fill)
447 		fill += bs;
448 
449 	k = j;
450 	j += (fill - min_fill) / sizeof(u32);
451 	if (j * 4 > bufsize) {
452 		pr_err("%s OVERFLOW %llu\n", __func__, j);
453 		return 0;
454 	}
455 	for (; k < j; k++)
456 		buf[k] = 0;
457 
458 	if (le) {
459 		/* MD5 */
460 		lebits = (__le64 *)&buf[j];
461 		*lebits = cpu_to_le64(byte_count << 3);
462 		j += 2;
463 	} else {
464 		if (bs == 64) {
465 			/* sha1 sha224 sha256 */
466 			bebits = (__be64 *)&buf[j];
467 			*bebits = cpu_to_be64(byte_count << 3);
468 			j += 2;
469 		} else {
470 			/* sha384 sha512*/
471 			bebits = (__be64 *)&buf[j];
472 			*bebits = cpu_to_be64(byte_count >> 61);
473 			j += 2;
474 			bebits = (__be64 *)&buf[j];
475 			*bebits = cpu_to_be64(byte_count << 3);
476 			j += 2;
477 		}
478 	}
479 	if (j * 4 > bufsize) {
480 		pr_err("%s OVERFLOW %llu\n", __func__, j);
481 		return 0;
482 	}
483 
484 	return j;
485 }
486 
487 /* sun8i_ss_hash_run - run an ahash request
488  * Send the data of the request to the SS along with an extra SG with padding
489  */
490 int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq)
491 {
492 	struct ahash_request *areq = container_of(breq, struct ahash_request, base);
493 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
494 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
495 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
496 	struct ahash_alg *alg = crypto_ahash_alg(tfm);
497 	struct sun8i_ss_alg_template *algt;
498 	struct sun8i_ss_dev *ss;
499 	struct scatterlist *sg;
500 	int bs = crypto_ahash_blocksize(tfm);
501 	int nr_sgs, err, digestsize;
502 	unsigned int len;
503 	u64 byte_count;
504 	void *pad, *result;
505 	int j, i, k, todo;
506 	dma_addr_t addr_res, addr_pad, addr_xpad;
507 	__le32 *bf;
508 	/* HMAC step:
509 	 * 0: normal hashing
510 	 * 1: IPAD
511 	 * 2: OPAD
512 	 */
513 	int hmac = 0;
514 
515 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash.base);
516 	ss = algt->ss;
517 
518 	digestsize = crypto_ahash_digestsize(tfm);
519 	if (digestsize == SHA224_DIGEST_SIZE)
520 		digestsize = SHA256_DIGEST_SIZE;
521 
522 	result = ss->flows[rctx->flow].result;
523 	pad = ss->flows[rctx->flow].pad;
524 	bf = (__le32 *)pad;
525 
526 	for (i = 0; i < MAX_SG; i++) {
527 		rctx->t_dst[i].addr = 0;
528 		rctx->t_dst[i].len = 0;
529 	}
530 
531 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
532 	algt->stat_req++;
533 #endif
534 
535 	rctx->method = ss->variant->alg_hash[algt->ss_algo_id];
536 
537 	nr_sgs = dma_map_sg(ss->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);
538 	if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
539 		dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
540 		err = -EINVAL;
541 		goto theend;
542 	}
543 
544 	addr_res = dma_map_single(ss->dev, result, digestsize, DMA_FROM_DEVICE);
545 	if (dma_mapping_error(ss->dev, addr_res)) {
546 		dev_err(ss->dev, "DMA map dest\n");
547 		err = -EINVAL;
548 		goto err_dma_result;
549 	}
550 
551 	j = 0;
552 	len = areq->nbytes;
553 	sg = areq->src;
554 	i = 0;
555 	while (len > 0 && sg) {
556 		if (sg_dma_len(sg) == 0) {
557 			sg = sg_next(sg);
558 			continue;
559 		}
560 		todo = min(len, sg_dma_len(sg));
561 		/* only the last SG could be with a size not modulo64 */
562 		if (todo % 64 == 0) {
563 			rctx->t_src[i].addr = sg_dma_address(sg);
564 			rctx->t_src[i].len = todo / 4;
565 			rctx->t_dst[i].addr = addr_res;
566 			rctx->t_dst[i].len = digestsize / 4;
567 			len -= todo;
568 		} else {
569 			scatterwalk_map_and_copy(bf, sg, 0, todo, 0);
570 			j += todo / 4;
571 			len -= todo;
572 		}
573 		sg = sg_next(sg);
574 		i++;
575 	}
576 	if (len > 0) {
577 		dev_err(ss->dev, "remaining len %d\n", len);
578 		err = -EINVAL;
579 		goto theend;
580 	}
581 
582 	if (j > 0)
583 		i--;
584 
585 retry:
586 	byte_count = areq->nbytes;
587 	if (tfmctx->keylen && hmac == 0) {
588 		hmac = 1;
589 		/* shift all SG one slot up, to free slot 0 for IPAD */
590 		for (k = 6; k >= 0; k--) {
591 			rctx->t_src[k + 1].addr = rctx->t_src[k].addr;
592 			rctx->t_src[k + 1].len = rctx->t_src[k].len;
593 			rctx->t_dst[k + 1].addr = rctx->t_dst[k].addr;
594 			rctx->t_dst[k + 1].len = rctx->t_dst[k].len;
595 		}
596 		addr_xpad = dma_map_single(ss->dev, tfmctx->ipad, bs, DMA_TO_DEVICE);
597 		err = dma_mapping_error(ss->dev, addr_xpad);
598 		if (err) {
599 			dev_err(ss->dev, "Fail to create DMA mapping of ipad\n");
600 			goto err_dma_xpad;
601 		}
602 		rctx->t_src[0].addr = addr_xpad;
603 		rctx->t_src[0].len = bs / 4;
604 		rctx->t_dst[0].addr = addr_res;
605 		rctx->t_dst[0].len = digestsize / 4;
606 		i++;
607 		byte_count = areq->nbytes + bs;
608 	}
609 	if (tfmctx->keylen && hmac == 2) {
610 		for (i = 0; i < MAX_SG; i++) {
611 			rctx->t_src[i].addr = 0;
612 			rctx->t_src[i].len = 0;
613 			rctx->t_dst[i].addr = 0;
614 			rctx->t_dst[i].len = 0;
615 		}
616 
617 		addr_res = dma_map_single(ss->dev, result, digestsize, DMA_FROM_DEVICE);
618 		if (dma_mapping_error(ss->dev, addr_res)) {
619 			dev_err(ss->dev, "Fail to create DMA mapping of result\n");
620 			err = -EINVAL;
621 			goto err_dma_result;
622 		}
623 		addr_xpad = dma_map_single(ss->dev, tfmctx->opad, bs, DMA_TO_DEVICE);
624 		err = dma_mapping_error(ss->dev, addr_xpad);
625 		if (err) {
626 			dev_err(ss->dev, "Fail to create DMA mapping of opad\n");
627 			goto err_dma_xpad;
628 		}
629 		rctx->t_src[0].addr = addr_xpad;
630 		rctx->t_src[0].len = bs / 4;
631 
632 		memcpy(bf, result, digestsize);
633 		j = digestsize / 4;
634 		i = 1;
635 		byte_count = digestsize + bs;
636 
637 		rctx->t_dst[0].addr = addr_res;
638 		rctx->t_dst[0].len = digestsize / 4;
639 	}
640 
641 	switch (algt->ss_algo_id) {
642 	case SS_ID_HASH_MD5:
643 		j = hash_pad(bf, 4096, j, byte_count, true, bs);
644 		break;
645 	case SS_ID_HASH_SHA1:
646 	case SS_ID_HASH_SHA224:
647 	case SS_ID_HASH_SHA256:
648 		j = hash_pad(bf, 4096, j, byte_count, false, bs);
649 		break;
650 	}
651 	if (!j) {
652 		err = -EINVAL;
653 		goto theend;
654 	}
655 
656 	addr_pad = dma_map_single(ss->dev, pad, j * 4, DMA_TO_DEVICE);
657 	if (dma_mapping_error(ss->dev, addr_pad)) {
658 		dev_err(ss->dev, "DMA error on padding SG\n");
659 		err = -EINVAL;
660 		goto err_dma_pad;
661 	}
662 	rctx->t_src[i].addr = addr_pad;
663 	rctx->t_src[i].len = j;
664 	rctx->t_dst[i].addr = addr_res;
665 	rctx->t_dst[i].len = digestsize / 4;
666 
667 	err = sun8i_ss_run_hash_task(ss, rctx, crypto_tfm_alg_name(areq->base.tfm));
668 
669 	/*
670 	 * mini helper for checking dma map/unmap
671 	 * flow start for hmac = 0 (and HMAC = 1)
672 	 * HMAC = 0
673 	 * MAP src
674 	 * MAP res
675 	 *
676 	 * retry:
677 	 * if hmac then hmac = 1
678 	 *	MAP xpad (ipad)
679 	 * if hmac == 2
680 	 *	MAP res
681 	 *	MAP xpad (opad)
682 	 * MAP pad
683 	 * ACTION!
684 	 * UNMAP pad
685 	 * if hmac
686 	 *	UNMAP xpad
687 	 * UNMAP res
688 	 * if hmac < 2
689 	 *	UNMAP SRC
690 	 *
691 	 * if hmac = 1 then hmac = 2 goto retry
692 	 */
693 
694 	dma_unmap_single(ss->dev, addr_pad, j * 4, DMA_TO_DEVICE);
695 
696 err_dma_pad:
697 	if (hmac > 0)
698 		dma_unmap_single(ss->dev, addr_xpad, bs, DMA_TO_DEVICE);
699 err_dma_xpad:
700 	dma_unmap_single(ss->dev, addr_res, digestsize, DMA_FROM_DEVICE);
701 err_dma_result:
702 	if (hmac < 2)
703 		dma_unmap_sg(ss->dev, areq->src, sg_nents(areq->src),
704 			     DMA_TO_DEVICE);
705 	if (hmac == 1 && !err) {
706 		hmac = 2;
707 		goto retry;
708 	}
709 
710 	if (!err)
711 		memcpy(areq->result, result, crypto_ahash_digestsize(tfm));
712 theend:
713 	local_bh_disable();
714 	crypto_finalize_hash_request(engine, breq, err);
715 	local_bh_enable();
716 	return 0;
717 }
718