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/bottom_half.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/scatterlist.h>
16 #include <crypto/internal/hash.h>
17 #include <crypto/sha1.h>
18 #include <crypto/sha2.h>
19 #include <crypto/md5.h>
20 #include "sun8i-ss.h"
21 
22 int sun8i_ss_hash_crainit(struct crypto_tfm *tfm)
23 {
24 	struct sun8i_ss_hash_tfm_ctx *op = crypto_tfm_ctx(tfm);
25 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->__crt_alg);
26 	struct sun8i_ss_alg_template *algt;
27 	int err;
28 
29 	memset(op, 0, sizeof(struct sun8i_ss_hash_tfm_ctx));
30 
31 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
32 	op->ss = algt->ss;
33 
34 	op->enginectx.op.do_one_request = sun8i_ss_hash_run;
35 	op->enginectx.op.prepare_request = NULL;
36 	op->enginectx.op.unprepare_request = NULL;
37 
38 	/* FALLBACK */
39 	op->fallback_tfm = crypto_alloc_ahash(crypto_tfm_alg_name(tfm), 0,
40 					      CRYPTO_ALG_NEED_FALLBACK);
41 	if (IS_ERR(op->fallback_tfm)) {
42 		dev_err(algt->ss->dev, "Fallback driver could no be loaded\n");
43 		return PTR_ERR(op->fallback_tfm);
44 	}
45 
46 	if (algt->alg.hash.halg.statesize < crypto_ahash_statesize(op->fallback_tfm))
47 		algt->alg.hash.halg.statesize = crypto_ahash_statesize(op->fallback_tfm);
48 
49 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
50 				 sizeof(struct sun8i_ss_hash_reqctx) +
51 				 crypto_ahash_reqsize(op->fallback_tfm));
52 
53 	dev_info(op->ss->dev, "Fallback for %s is %s\n",
54 		 crypto_tfm_alg_driver_name(tfm),
55 		 crypto_tfm_alg_driver_name(&op->fallback_tfm->base));
56 	err = pm_runtime_get_sync(op->ss->dev);
57 	if (err < 0)
58 		goto error_pm;
59 	return 0;
60 error_pm:
61 	pm_runtime_put_noidle(op->ss->dev);
62 	crypto_free_ahash(op->fallback_tfm);
63 	return err;
64 }
65 
66 void sun8i_ss_hash_craexit(struct crypto_tfm *tfm)
67 {
68 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_tfm_ctx(tfm);
69 
70 	crypto_free_ahash(tfmctx->fallback_tfm);
71 	pm_runtime_put_sync_suspend(tfmctx->ss->dev);
72 }
73 
74 int sun8i_ss_hash_init(struct ahash_request *areq)
75 {
76 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
77 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
78 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
79 
80 	memset(rctx, 0, sizeof(struct sun8i_ss_hash_reqctx));
81 
82 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
83 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
84 
85 	return crypto_ahash_init(&rctx->fallback_req);
86 }
87 
88 int sun8i_ss_hash_export(struct ahash_request *areq, void *out)
89 {
90 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
91 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
92 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
93 
94 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
95 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
96 
97 	return crypto_ahash_export(&rctx->fallback_req, out);
98 }
99 
100 int sun8i_ss_hash_import(struct ahash_request *areq, const void *in)
101 {
102 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
103 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
104 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
105 
106 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
107 	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;
108 
109 	return crypto_ahash_import(&rctx->fallback_req, in);
110 }
111 
112 int sun8i_ss_hash_final(struct ahash_request *areq)
113 {
114 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
115 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
116 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
117 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
118 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
119 	struct sun8i_ss_alg_template *algt;
120 #endif
121 
122 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
123 	rctx->fallback_req.base.flags = areq->base.flags &
124 					CRYPTO_TFM_REQ_MAY_SLEEP;
125 	rctx->fallback_req.result = areq->result;
126 
127 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
128 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
129 	algt->stat_fb++;
130 #endif
131 
132 	return crypto_ahash_final(&rctx->fallback_req);
133 }
134 
135 int sun8i_ss_hash_update(struct ahash_request *areq)
136 {
137 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
138 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
139 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
140 
141 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
142 	rctx->fallback_req.base.flags = areq->base.flags &
143 					CRYPTO_TFM_REQ_MAY_SLEEP;
144 	rctx->fallback_req.nbytes = areq->nbytes;
145 	rctx->fallback_req.src = areq->src;
146 
147 	return crypto_ahash_update(&rctx->fallback_req);
148 }
149 
150 int sun8i_ss_hash_finup(struct ahash_request *areq)
151 {
152 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
153 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
154 	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
155 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
156 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
157 	struct sun8i_ss_alg_template *algt;
158 #endif
159 
160 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
161 	rctx->fallback_req.base.flags = areq->base.flags &
162 					CRYPTO_TFM_REQ_MAY_SLEEP;
163 
164 	rctx->fallback_req.nbytes = areq->nbytes;
165 	rctx->fallback_req.src = areq->src;
166 	rctx->fallback_req.result = areq->result;
167 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
168 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
169 	algt->stat_fb++;
170 #endif
171 
172 	return crypto_ahash_finup(&rctx->fallback_req);
173 }
174 
175 static int sun8i_ss_hash_digest_fb(struct ahash_request *areq)
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 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
181 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
182 	struct sun8i_ss_alg_template *algt;
183 #endif
184 
185 	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
186 	rctx->fallback_req.base.flags = areq->base.flags &
187 					CRYPTO_TFM_REQ_MAY_SLEEP;
188 
189 	rctx->fallback_req.nbytes = areq->nbytes;
190 	rctx->fallback_req.src = areq->src;
191 	rctx->fallback_req.result = areq->result;
192 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
193 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
194 	algt->stat_fb++;
195 #endif
196 
197 	return crypto_ahash_digest(&rctx->fallback_req);
198 }
199 
200 static int sun8i_ss_run_hash_task(struct sun8i_ss_dev *ss,
201 				  struct sun8i_ss_hash_reqctx *rctx,
202 				  const char *name)
203 {
204 	int flow = rctx->flow;
205 	u32 v = SS_START;
206 	int i;
207 
208 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
209 	ss->flows[flow].stat_req++;
210 #endif
211 
212 	/* choose between stream0/stream1 */
213 	if (flow)
214 		v |= SS_FLOW1;
215 	else
216 		v |= SS_FLOW0;
217 
218 	v |= rctx->method;
219 
220 	for (i = 0; i < MAX_SG; i++) {
221 		if (!rctx->t_dst[i].addr)
222 			break;
223 
224 		mutex_lock(&ss->mlock);
225 		if (i > 0) {
226 			v |= BIT(17);
227 			writel(rctx->t_dst[i - 1].addr, ss->base + SS_KEY_ADR_REG);
228 			writel(rctx->t_dst[i - 1].addr, ss->base + SS_IV_ADR_REG);
229 		}
230 
231 		dev_dbg(ss->dev,
232 			"Processing SG %d on flow %d %s ctl=%x %d to %d method=%x src=%x dst=%x\n",
233 			i, flow, name, v,
234 			rctx->t_src[i].len, rctx->t_dst[i].len,
235 			rctx->method, rctx->t_src[i].addr, rctx->t_dst[i].addr);
236 
237 		writel(rctx->t_src[i].addr, ss->base + SS_SRC_ADR_REG);
238 		writel(rctx->t_dst[i].addr, ss->base + SS_DST_ADR_REG);
239 		writel(rctx->t_src[i].len, ss->base + SS_LEN_ADR_REG);
240 		writel(BIT(0) | BIT(1), ss->base + SS_INT_CTL_REG);
241 
242 		reinit_completion(&ss->flows[flow].complete);
243 		ss->flows[flow].status = 0;
244 		wmb();
245 
246 		writel(v, ss->base + SS_CTL_REG);
247 		mutex_unlock(&ss->mlock);
248 		wait_for_completion_interruptible_timeout(&ss->flows[flow].complete,
249 							  msecs_to_jiffies(2000));
250 		if (ss->flows[flow].status == 0) {
251 			dev_err(ss->dev, "DMA timeout for %s\n", name);
252 			return -EFAULT;
253 		}
254 	}
255 
256 	return 0;
257 }
258 
259 static bool sun8i_ss_hash_need_fallback(struct ahash_request *areq)
260 {
261 	struct scatterlist *sg;
262 
263 	if (areq->nbytes == 0)
264 		return true;
265 	/* we need to reserve one SG for the padding one */
266 	if (sg_nents(areq->src) > MAX_SG - 1)
267 		return true;
268 	sg = areq->src;
269 	while (sg) {
270 		/* SS can operate hash only on full block size
271 		 * since SS support only MD5,sha1,sha224 and sha256, blocksize
272 		 * is always 64
273 		 * TODO: handle request if last SG is not len%64
274 		 * but this will need to copy data on a new SG of size=64
275 		 */
276 		if (sg->length % 64 || !IS_ALIGNED(sg->offset, sizeof(u32)))
277 			return true;
278 		sg = sg_next(sg);
279 	}
280 	return false;
281 }
282 
283 int sun8i_ss_hash_digest(struct ahash_request *areq)
284 {
285 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
286 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
287 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
288 	struct sun8i_ss_alg_template *algt;
289 	struct sun8i_ss_dev *ss;
290 	struct crypto_engine *engine;
291 	struct scatterlist *sg;
292 	int nr_sgs, e, i;
293 
294 	if (sun8i_ss_hash_need_fallback(areq))
295 		return sun8i_ss_hash_digest_fb(areq);
296 
297 	nr_sgs = sg_nents(areq->src);
298 	if (nr_sgs > MAX_SG - 1)
299 		return sun8i_ss_hash_digest_fb(areq);
300 
301 	for_each_sg(areq->src, sg, nr_sgs, i) {
302 		if (sg->length % 4 || !IS_ALIGNED(sg->offset, sizeof(u32)))
303 			return sun8i_ss_hash_digest_fb(areq);
304 	}
305 
306 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
307 	ss = algt->ss;
308 
309 	e = sun8i_ss_get_engine_number(ss);
310 	rctx->flow = e;
311 	engine = ss->flows[e].engine;
312 
313 	return crypto_transfer_hash_request_to_engine(engine, areq);
314 }
315 
316 /* sun8i_ss_hash_run - run an ahash request
317  * Send the data of the request to the SS along with an extra SG with padding
318  */
319 int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq)
320 {
321 	struct ahash_request *areq = container_of(breq, struct ahash_request, base);
322 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
323 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);
324 	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);
325 	struct sun8i_ss_alg_template *algt;
326 	struct sun8i_ss_dev *ss;
327 	struct scatterlist *sg;
328 	int nr_sgs, err, digestsize;
329 	unsigned int len;
330 	u64 fill, min_fill, byte_count;
331 	void *pad, *result;
332 	int j, i, todo;
333 	__be64 *bebits;
334 	__le64 *lebits;
335 	dma_addr_t addr_res, addr_pad;
336 	__le32 *bf;
337 
338 	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash);
339 	ss = algt->ss;
340 
341 	digestsize = algt->alg.hash.halg.digestsize;
342 	if (digestsize == SHA224_DIGEST_SIZE)
343 		digestsize = SHA256_DIGEST_SIZE;
344 
345 	/* the padding could be up to two block. */
346 	pad = kzalloc(algt->alg.hash.halg.base.cra_blocksize * 2, GFP_KERNEL | GFP_DMA);
347 	if (!pad)
348 		return -ENOMEM;
349 	bf = (__le32 *)pad;
350 
351 	result = kzalloc(digestsize, GFP_KERNEL | GFP_DMA);
352 	if (!result) {
353 		kfree(pad);
354 		return -ENOMEM;
355 	}
356 
357 	for (i = 0; i < MAX_SG; i++) {
358 		rctx->t_dst[i].addr = 0;
359 		rctx->t_dst[i].len = 0;
360 	}
361 
362 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
363 	algt->stat_req++;
364 #endif
365 
366 	rctx->method = ss->variant->alg_hash[algt->ss_algo_id];
367 
368 	nr_sgs = dma_map_sg(ss->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);
369 	if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
370 		dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
371 		err = -EINVAL;
372 		goto theend;
373 	}
374 
375 	addr_res = dma_map_single(ss->dev, result, digestsize, DMA_FROM_DEVICE);
376 	if (dma_mapping_error(ss->dev, addr_res)) {
377 		dev_err(ss->dev, "DMA map dest\n");
378 		err = -EINVAL;
379 		goto theend;
380 	}
381 
382 	len = areq->nbytes;
383 	for_each_sg(areq->src, sg, nr_sgs, i) {
384 		rctx->t_src[i].addr = sg_dma_address(sg);
385 		todo = min(len, sg_dma_len(sg));
386 		rctx->t_src[i].len = todo / 4;
387 		len -= todo;
388 		rctx->t_dst[i].addr = addr_res;
389 		rctx->t_dst[i].len = digestsize / 4;
390 	}
391 	if (len > 0) {
392 		dev_err(ss->dev, "remaining len %d\n", len);
393 		err = -EINVAL;
394 		goto theend;
395 	}
396 
397 	byte_count = areq->nbytes;
398 	j = 0;
399 	bf[j++] = cpu_to_le32(0x80);
400 
401 	fill = 64 - (byte_count % 64);
402 	min_fill = 3 * sizeof(u32);
403 
404 	if (fill < min_fill)
405 		fill += 64;
406 
407 	j += (fill - min_fill) / sizeof(u32);
408 
409 	switch (algt->ss_algo_id) {
410 	case SS_ID_HASH_MD5:
411 		lebits = (__le64 *)&bf[j];
412 		*lebits = cpu_to_le64(byte_count << 3);
413 		j += 2;
414 		break;
415 	case SS_ID_HASH_SHA1:
416 	case SS_ID_HASH_SHA224:
417 	case SS_ID_HASH_SHA256:
418 		bebits = (__be64 *)&bf[j];
419 		*bebits = cpu_to_be64(byte_count << 3);
420 		j += 2;
421 		break;
422 	}
423 
424 	addr_pad = dma_map_single(ss->dev, pad, j * 4, DMA_TO_DEVICE);
425 	rctx->t_src[i].addr = addr_pad;
426 	rctx->t_src[i].len = j;
427 	rctx->t_dst[i].addr = addr_res;
428 	rctx->t_dst[i].len = digestsize / 4;
429 	if (dma_mapping_error(ss->dev, addr_pad)) {
430 		dev_err(ss->dev, "DMA error on padding SG\n");
431 		err = -EINVAL;
432 		goto theend;
433 	}
434 
435 	err = sun8i_ss_run_hash_task(ss, rctx, crypto_tfm_alg_name(areq->base.tfm));
436 
437 	dma_unmap_single(ss->dev, addr_pad, j * 4, DMA_TO_DEVICE);
438 	dma_unmap_sg(ss->dev, areq->src, sg_nents(areq->src),
439 		     DMA_TO_DEVICE);
440 	dma_unmap_single(ss->dev, addr_res, digestsize, DMA_FROM_DEVICE);
441 
442 	memcpy(areq->result, result, algt->alg.hash.halg.digestsize);
443 theend:
444 	kfree(pad);
445 	kfree(result);
446 	local_bh_disable();
447 	crypto_finalize_hash_request(engine, breq, err);
448 	local_bh_enable();
449 	return 0;
450 }
451