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/arm/sunxi.rst
11  */
12 #include <linux/dma-mapping.h>
13 #include <linux/pm_runtime.h>
14 #include <linux/scatterlist.h>
15 #include <crypto/internal/hash.h>
16 #include <crypto/sha.h>
17 #include <crypto/md5.h>
18 #include "sun8i-ss.h"
19 
20 int sun8i_ss_hash_crainit(struct crypto_tfm *tfm)
21 {
22 	struct sun8i_ss_hash_tfm_ctx *op = crypto_tfm_ctx(tfm);
23 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->__crt_alg);
24 	struct sun8i_ss_alg_template *algt;
25 	int err;
26 
27 	memset(op, 0, sizeof(struct sun8i_ss_hash_tfm_ctx));
28 
29 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
30 	op->ss = algt->ss;
31 
32 	op->enginectx.op.do_one_request = sun8i_ss_hash_run;
33 	op->enginectx.op.prepare_request = NULL;
34 	op->enginectx.op.unprepare_request = NULL;
35 
36 	/* FALLBACK */
37 	op->fallback_tfm = crypto_alloc_ahash(crypto_tfm_alg_name(tfm), 0,
38 					      CRYPTO_ALG_NEED_FALLBACK);
39 	if (IS_ERR(op->fallback_tfm)) {
40 		dev_err(algt->ss->dev, "Fallback driver could no be loaded\n");
41 		return PTR_ERR(op->fallback_tfm);
42 	}
43 
44 	if (algt->alg.hash.halg.statesize < crypto_ahash_statesize(op->fallback_tfm))
45 		algt->alg.hash.halg.statesize = crypto_ahash_statesize(op->fallback_tfm);
46 
47 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
48 				 sizeof(struct sun8i_ss_hash_reqctx) +
49 				 crypto_ahash_reqsize(op->fallback_tfm));
50 
51 	dev_info(op->ss->dev, "Fallback for %s is %s\n",
52 		 crypto_tfm_alg_driver_name(tfm),
53 		 crypto_tfm_alg_driver_name(&op->fallback_tfm->base));
54 	err = pm_runtime_get_sync(op->ss->dev);
55 	if (err < 0)
56 		goto error_pm;
57 	return 0;
58 error_pm:
59 	pm_runtime_put_noidle(op->ss->dev);
60 	crypto_free_ahash(op->fallback_tfm);
61 	return err;
62 }
63 
64 void sun8i_ss_hash_craexit(struct crypto_tfm *tfm)
65 {
66 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_tfm_ctx(tfm);
67 
68 	crypto_free_ahash(tfmctx->fallback_tfm);
69 	pm_runtime_put_sync_suspend(tfmctx->ss->dev);
70 }
71 
72 int sun8i_ss_hash_init(struct ahash_request *areq)
73 {
74 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
75 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
76 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
77 
78 	memset(rctx, 0, sizeof(struct sun8i_ss_hash_reqctx));
79 
80 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
81 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
82 
83 	return crypto_ahash_init(&rctx->fallback_req);
84 }
85 
86 int sun8i_ss_hash_export(struct ahash_request *areq, void *out)
87 {
88 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
89 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
90 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
91 
92 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
93 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
94 
95 	return crypto_ahash_export(&rctx->fallback_req, out);
96 }
97 
98 int sun8i_ss_hash_import(struct ahash_request *areq, const void *in)
99 {
100 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
101 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
102 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
103 
104 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
105 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
106 
107 	return crypto_ahash_import(&rctx->fallback_req, in);
108 }
109 
110 int sun8i_ss_hash_final(struct ahash_request *areq)
111 {
112 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
113 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
114 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
115 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
116 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
117 	struct sun8i_ss_alg_template *algt;
118 #endif
119 
120 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
121 	rctx->fallback_req.base.flags = areq->base.flags &
122 					CRYPTO_TFM_REQ_MAY_SLEEP;
123 	rctx->fallback_req.result = areq->result;
124 
125 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
126 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
127 	algt->stat_fb++;
128 #endif
129 
130 	return crypto_ahash_final(&rctx->fallback_req);
131 }
132 
133 int sun8i_ss_hash_update(struct ahash_request *areq)
134 {
135 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
136 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
137 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
138 
139 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
140 	rctx->fallback_req.base.flags = areq->base.flags &
141 					CRYPTO_TFM_REQ_MAY_SLEEP;
142 	rctx->fallback_req.nbytes = areq->nbytes;
143 	rctx->fallback_req.src = areq->src;
144 
145 	return crypto_ahash_update(&rctx->fallback_req);
146 }
147 
148 int sun8i_ss_hash_finup(struct ahash_request *areq)
149 {
150 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
151 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
152 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
153 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
154 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
155 	struct sun8i_ss_alg_template *algt;
156 #endif
157 
158 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
159 	rctx->fallback_req.base.flags = areq->base.flags &
160 					CRYPTO_TFM_REQ_MAY_SLEEP;
161 
162 	rctx->fallback_req.nbytes = areq->nbytes;
163 	rctx->fallback_req.src = areq->src;
164 	rctx->fallback_req.result = areq->result;
165 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
166 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
167 	algt->stat_fb++;
168 #endif
169 
170 	return crypto_ahash_finup(&rctx->fallback_req);
171 }
172 
173 static int sun8i_ss_hash_digest_fb(struct ahash_request *areq)
174 {
175 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
176 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
177 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
178 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
179 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
180 	struct sun8i_ss_alg_template *algt;
181 #endif
182 
183 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
184 	rctx->fallback_req.base.flags = areq->base.flags &
185 					CRYPTO_TFM_REQ_MAY_SLEEP;
186 
187 	rctx->fallback_req.nbytes = areq->nbytes;
188 	rctx->fallback_req.src = areq->src;
189 	rctx->fallback_req.result = areq->result;
190 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
191 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
192 	algt->stat_fb++;
193 #endif
194 
195 	return crypto_ahash_digest(&rctx->fallback_req);
196 }
197 
198 static int sun8i_ss_run_hash_task(struct sun8i_ss_dev *ss,
199 				  struct sun8i_ss_hash_reqctx *rctx,
200 				  const char *name)
201 {
202 	int flow = rctx->flow;
203 	u32 v = SS_START;
204 	int i;
205 
206 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
207 	ss->flows[flow].stat_req++;
208 #endif
209 
210 	/* choose between stream0/stream1 */
211 	if (flow)
212 		v |= SS_FLOW1;
213 	else
214 		v |= SS_FLOW0;
215 
216 	v |= rctx->method;
217 
218 	for (i = 0; i < MAX_SG; i++) {
219 		if (!rctx->t_dst[i].addr)
220 			break;
221 
222 		mutex_lock(&ss->mlock);
223 		if (i > 0) {
224 			v |= BIT(17);
225 			writel(rctx->t_dst[i - 1].addr, ss->base + SS_KEY_ADR_REG);
226 			writel(rctx->t_dst[i - 1].addr, ss->base + SS_IV_ADR_REG);
227 		}
228 
229 		dev_dbg(ss->dev,
230 			"Processing SG %d on flow %d %s ctl=%x %d to %d method=%x src=%x dst=%x\n",
231 			i, flow, name, v,
232 			rctx->t_src[i].len, rctx->t_dst[i].len,
233 			rctx->method, rctx->t_src[i].addr, rctx->t_dst[i].addr);
234 
235 		writel(rctx->t_src[i].addr, ss->base + SS_SRC_ADR_REG);
236 		writel(rctx->t_dst[i].addr, ss->base + SS_DST_ADR_REG);
237 		writel(rctx->t_src[i].len, ss->base + SS_LEN_ADR_REG);
238 		writel(BIT(0) | BIT(1), ss->base + SS_INT_CTL_REG);
239 
240 		reinit_completion(&ss->flows[flow].complete);
241 		ss->flows[flow].status = 0;
242 		wmb();
243 
244 		writel(v, ss->base + SS_CTL_REG);
245 		mutex_unlock(&ss->mlock);
246 		wait_for_completion_interruptible_timeout(&ss->flows[flow].complete,
247 							  msecs_to_jiffies(2000));
248 		if (ss->flows[flow].status == 0) {
249 			dev_err(ss->dev, "DMA timeout for %s\n", name);
250 			return -EFAULT;
251 		}
252 	}
253 
254 	return 0;
255 }
256 
257 static bool sun8i_ss_hash_need_fallback(struct ahash_request *areq)
258 {
259 	struct scatterlist *sg;
260 
261 	if (areq->nbytes == 0)
262 		return true;
263 	/* we need to reserve one SG for the padding one */
264 	if (sg_nents(areq->src) > MAX_SG - 1)
265 		return true;
266 	sg = areq->src;
267 	while (sg) {
268 		/* SS can operate hash only on full block size
269 		 * since SS support only MD5,sha1,sha224 and sha256, blocksize
270 		 * is always 64
271 		 * TODO: handle request if last SG is not len%64
272 		 * but this will need to copy data on a new SG of size=64
273 		 */
274 		if (sg->length % 64 || !IS_ALIGNED(sg->offset, sizeof(u32)))
275 			return true;
276 		sg = sg_next(sg);
277 	}
278 	return false;
279 }
280 
281 int sun8i_ss_hash_digest(struct ahash_request *areq)
282 {
283 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
284 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
285 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
286 	struct sun8i_ss_alg_template *algt;
287 	struct sun8i_ss_dev *ss;
288 	struct crypto_engine *engine;
289 	struct scatterlist *sg;
290 	int nr_sgs, e, i;
291 
292 	if (sun8i_ss_hash_need_fallback(areq))
293 		return sun8i_ss_hash_digest_fb(areq);
294 
295 	nr_sgs = sg_nents(areq->src);
296 	if (nr_sgs > MAX_SG - 1)
297 		return sun8i_ss_hash_digest_fb(areq);
298 
299 	for_each_sg(areq->src, sg, nr_sgs, i) {
300 		if (sg->length % 4 || !IS_ALIGNED(sg->offset, sizeof(u32)))
301 			return sun8i_ss_hash_digest_fb(areq);
302 	}
303 
304 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
305 	ss = algt->ss;
306 
307 	e = sun8i_ss_get_engine_number(ss);
308 	rctx->flow = e;
309 	engine = ss->flows[e].engine;
310 
311 	return crypto_transfer_hash_request_to_engine(engine, areq);
312 }
313 
314 /* sun8i_ss_hash_run - run an ahash request
315  * Send the data of the request to the SS along with an extra SG with padding
316  */
317 int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq)
318 {
319 	struct ahash_request *areq = container_of(breq, struct ahash_request, base);
320 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
321 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
322 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
323 	struct sun8i_ss_alg_template *algt;
324 	struct sun8i_ss_dev *ss;
325 	struct scatterlist *sg;
326 	int nr_sgs, err, digestsize;
327 	unsigned int len;
328 	u64 fill, min_fill, byte_count;
329 	void *pad, *result;
330 	int j, i, todo;
331 	__be64 *bebits;
332 	__le64 *lebits;
333 	dma_addr_t addr_res, addr_pad;
334 	__le32 *bf;
335 
336 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
337 	ss = algt->ss;
338 
339 	digestsize = algt->alg.hash.halg.digestsize;
340 	if (digestsize == SHA224_DIGEST_SIZE)
341 		digestsize = SHA256_DIGEST_SIZE;
342 
343 	/* the padding could be up to two block. */
344 	pad = kzalloc(algt->alg.hash.halg.base.cra_blocksize * 2, GFP_KERNEL | GFP_DMA);
345 	if (!pad)
346 		return -ENOMEM;
347 	bf = (__le32 *)pad;
348 
349 	result = kzalloc(digestsize, GFP_KERNEL | GFP_DMA);
350 	if (!result)
351 		return -ENOMEM;
352 
353 	for (i = 0; i < MAX_SG; i++) {
354 		rctx->t_dst[i].addr = 0;
355 		rctx->t_dst[i].len = 0;
356 	}
357 
358 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
359 	algt->stat_req++;
360 #endif
361 
362 	rctx->method = ss->variant->alg_hash[algt->ss_algo_id];
363 
364 	nr_sgs = dma_map_sg(ss->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);
365 	if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
366 		dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
367 		err = -EINVAL;
368 		goto theend;
369 	}
370 
371 	addr_res = dma_map_single(ss->dev, result, digestsize, DMA_FROM_DEVICE);
372 	if (dma_mapping_error(ss->dev, addr_res)) {
373 		dev_err(ss->dev, "DMA map dest\n");
374 		err = -EINVAL;
375 		goto theend;
376 	}
377 
378 	len = areq->nbytes;
379 	for_each_sg(areq->src, sg, nr_sgs, i) {
380 		rctx->t_src[i].addr = sg_dma_address(sg);
381 		todo = min(len, sg_dma_len(sg));
382 		rctx->t_src[i].len = todo / 4;
383 		len -= todo;
384 		rctx->t_dst[i].addr = addr_res;
385 		rctx->t_dst[i].len = digestsize / 4;
386 	}
387 	if (len > 0) {
388 		dev_err(ss->dev, "remaining len %d\n", len);
389 		err = -EINVAL;
390 		goto theend;
391 	}
392 
393 	byte_count = areq->nbytes;
394 	j = 0;
395 	bf[j++] = cpu_to_le32(0x80);
396 
397 	fill = 64 - (byte_count % 64);
398 	min_fill = 3 * sizeof(u32);
399 
400 	if (fill < min_fill)
401 		fill += 64;
402 
403 	j += (fill - min_fill) / sizeof(u32);
404 
405 	switch (algt->ss_algo_id) {
406 	case SS_ID_HASH_MD5:
407 		lebits = (__le64 *)&bf[j];
408 		*lebits = cpu_to_le64(byte_count << 3);
409 		j += 2;
410 		break;
411 	case SS_ID_HASH_SHA1:
412 	case SS_ID_HASH_SHA224:
413 	case SS_ID_HASH_SHA256:
414 		bebits = (__be64 *)&bf[j];
415 		*bebits = cpu_to_be64(byte_count << 3);
416 		j += 2;
417 		break;
418 	}
419 
420 	addr_pad = dma_map_single(ss->dev, pad, j * 4, DMA_TO_DEVICE);
421 	rctx->t_src[i].addr = addr_pad;
422 	rctx->t_src[i].len = j;
423 	rctx->t_dst[i].addr = addr_res;
424 	rctx->t_dst[i].len = digestsize / 4;
425 	if (dma_mapping_error(ss->dev, addr_pad)) {
426 		dev_err(ss->dev, "DMA error on padding SG\n");
427 		err = -EINVAL;
428 		goto theend;
429 	}
430 
431 	err = sun8i_ss_run_hash_task(ss, rctx, crypto_tfm_alg_name(areq->base.tfm));
432 
433 	dma_unmap_single(ss->dev, addr_pad, j * 4, DMA_TO_DEVICE);
434 	dma_unmap_sg(ss->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
435 	dma_unmap_single(ss->dev, addr_res, digestsize, DMA_FROM_DEVICE);
436 
437 	kfree(pad);
438 
439 	memcpy(areq->result, result, algt->alg.hash.halg.digestsize);
440 	kfree(result);
441 theend:
442 	crypto_finalize_hash_request(engine, breq, err);
443 	return 0;
444 }
445