xref: /linux/drivers/crypto/caam/caampkc.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
2 /*
3  * caam - Freescale FSL CAAM support for Public Key Cryptography
4  *
5  * Copyright 2016 Freescale Semiconductor, Inc.
6  * Copyright 2018-2019 NXP
7  *
8  * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
9  * all the desired key parameters, input and output pointers.
10  */
11 #include "compat.h"
12 #include "regs.h"
13 #include "intern.h"
14 #include "jr.h"
15 #include "error.h"
16 #include "desc_constr.h"
17 #include "sg_sw_sec4.h"
18 #include "caampkc.h"
19 
20 #define DESC_RSA_PUB_LEN	(2 * CAAM_CMD_SZ + SIZEOF_RSA_PUB_PDB)
21 #define DESC_RSA_PRIV_F1_LEN	(2 * CAAM_CMD_SZ + \
22 				 SIZEOF_RSA_PRIV_F1_PDB)
23 #define DESC_RSA_PRIV_F2_LEN	(2 * CAAM_CMD_SZ + \
24 				 SIZEOF_RSA_PRIV_F2_PDB)
25 #define DESC_RSA_PRIV_F3_LEN	(2 * CAAM_CMD_SZ + \
26 				 SIZEOF_RSA_PRIV_F3_PDB)
27 #define CAAM_RSA_MAX_INPUT_SIZE	512 /* for a 4096-bit modulus */
28 
29 /* buffer filled with zeros, used for padding */
30 static u8 *zero_buffer;
31 
32 /*
33  * variable used to avoid double free of resources in case
34  * algorithm registration was unsuccessful
35  */
36 static bool init_done;
37 
38 struct caam_akcipher_alg {
39 	struct akcipher_alg akcipher;
40 	bool registered;
41 };
42 
43 static void rsa_io_unmap(struct device *dev, struct rsa_edesc *edesc,
44 			 struct akcipher_request *req)
45 {
46 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
47 
48 	dma_unmap_sg(dev, req->dst, edesc->dst_nents, DMA_FROM_DEVICE);
49 	dma_unmap_sg(dev, req_ctx->fixup_src, edesc->src_nents, DMA_TO_DEVICE);
50 
51 	if (edesc->sec4_sg_bytes)
52 		dma_unmap_single(dev, edesc->sec4_sg_dma, edesc->sec4_sg_bytes,
53 				 DMA_TO_DEVICE);
54 }
55 
56 static void rsa_pub_unmap(struct device *dev, struct rsa_edesc *edesc,
57 			  struct akcipher_request *req)
58 {
59 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
60 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
61 	struct caam_rsa_key *key = &ctx->key;
62 	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
63 
64 	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
65 	dma_unmap_single(dev, pdb->e_dma, key->e_sz, DMA_TO_DEVICE);
66 }
67 
68 static void rsa_priv_f1_unmap(struct device *dev, struct rsa_edesc *edesc,
69 			      struct akcipher_request *req)
70 {
71 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
72 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
73 	struct caam_rsa_key *key = &ctx->key;
74 	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
75 
76 	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
77 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
78 }
79 
80 static void rsa_priv_f2_unmap(struct device *dev, struct rsa_edesc *edesc,
81 			      struct akcipher_request *req)
82 {
83 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
84 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
85 	struct caam_rsa_key *key = &ctx->key;
86 	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
87 	size_t p_sz = key->p_sz;
88 	size_t q_sz = key->q_sz;
89 
90 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
91 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
92 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
93 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
94 	dma_unmap_single(dev, pdb->tmp2_dma, q_sz, DMA_BIDIRECTIONAL);
95 }
96 
97 static void rsa_priv_f3_unmap(struct device *dev, struct rsa_edesc *edesc,
98 			      struct akcipher_request *req)
99 {
100 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
101 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
102 	struct caam_rsa_key *key = &ctx->key;
103 	struct rsa_priv_f3_pdb *pdb = &edesc->pdb.priv_f3;
104 	size_t p_sz = key->p_sz;
105 	size_t q_sz = key->q_sz;
106 
107 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
108 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
109 	dma_unmap_single(dev, pdb->dp_dma, p_sz, DMA_TO_DEVICE);
110 	dma_unmap_single(dev, pdb->dq_dma, q_sz, DMA_TO_DEVICE);
111 	dma_unmap_single(dev, pdb->c_dma, p_sz, DMA_TO_DEVICE);
112 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
113 	dma_unmap_single(dev, pdb->tmp2_dma, q_sz, DMA_BIDIRECTIONAL);
114 }
115 
116 /* RSA Job Completion handler */
117 static void rsa_pub_done(struct device *dev, u32 *desc, u32 err, void *context)
118 {
119 	struct akcipher_request *req = context;
120 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
121 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
122 	struct rsa_edesc *edesc;
123 	int ecode = 0;
124 	bool has_bklog;
125 
126 	if (err)
127 		ecode = caam_jr_strstatus(dev, err);
128 
129 	edesc = req_ctx->edesc;
130 	has_bklog = edesc->bklog;
131 
132 	rsa_pub_unmap(dev, edesc, req);
133 	rsa_io_unmap(dev, edesc, req);
134 	kfree(edesc);
135 
136 	/*
137 	 * If no backlog flag, the completion of the request is done
138 	 * by CAAM, not crypto engine.
139 	 */
140 	if (!has_bklog)
141 		akcipher_request_complete(req, ecode);
142 	else
143 		crypto_finalize_akcipher_request(jrp->engine, req, ecode);
144 }
145 
146 static void rsa_priv_f_done(struct device *dev, u32 *desc, u32 err,
147 			    void *context)
148 {
149 	struct akcipher_request *req = context;
150 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
151 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
152 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
153 	struct caam_rsa_key *key = &ctx->key;
154 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
155 	struct rsa_edesc *edesc;
156 	int ecode = 0;
157 	bool has_bklog;
158 
159 	if (err)
160 		ecode = caam_jr_strstatus(dev, err);
161 
162 	edesc = req_ctx->edesc;
163 	has_bklog = edesc->bklog;
164 
165 	switch (key->priv_form) {
166 	case FORM1:
167 		rsa_priv_f1_unmap(dev, edesc, req);
168 		break;
169 	case FORM2:
170 		rsa_priv_f2_unmap(dev, edesc, req);
171 		break;
172 	case FORM3:
173 		rsa_priv_f3_unmap(dev, edesc, req);
174 	}
175 
176 	rsa_io_unmap(dev, edesc, req);
177 	kfree(edesc);
178 
179 	/*
180 	 * If no backlog flag, the completion of the request is done
181 	 * by CAAM, not crypto engine.
182 	 */
183 	if (!has_bklog)
184 		akcipher_request_complete(req, ecode);
185 	else
186 		crypto_finalize_akcipher_request(jrp->engine, req, ecode);
187 }
188 
189 /**
190  * caam_rsa_count_leading_zeros - Count leading zeros, need it to strip,
191  *                                from a given scatterlist
192  *
193  * @sgl   : scatterlist to count zeros from
194  * @nbytes: number of zeros, in bytes, to strip
195  * @flags : operation flags
196  */
197 static int caam_rsa_count_leading_zeros(struct scatterlist *sgl,
198 					unsigned int nbytes,
199 					unsigned int flags)
200 {
201 	struct sg_mapping_iter miter;
202 	int lzeros, ents;
203 	unsigned int len;
204 	unsigned int tbytes = nbytes;
205 	const u8 *buff;
206 
207 	ents = sg_nents_for_len(sgl, nbytes);
208 	if (ents < 0)
209 		return ents;
210 
211 	sg_miter_start(&miter, sgl, ents, SG_MITER_FROM_SG | flags);
212 
213 	lzeros = 0;
214 	len = 0;
215 	while (nbytes > 0) {
216 		/* do not strip more than given bytes */
217 		while (len && !*buff && lzeros < nbytes) {
218 			lzeros++;
219 			len--;
220 			buff++;
221 		}
222 
223 		if (len && *buff)
224 			break;
225 
226 		sg_miter_next(&miter);
227 		buff = miter.addr;
228 		len = miter.length;
229 
230 		nbytes -= lzeros;
231 		lzeros = 0;
232 	}
233 
234 	miter.consumed = lzeros;
235 	sg_miter_stop(&miter);
236 	nbytes -= lzeros;
237 
238 	return tbytes - nbytes;
239 }
240 
241 static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req,
242 					 size_t desclen)
243 {
244 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
245 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
246 	struct device *dev = ctx->dev;
247 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
248 	struct caam_rsa_key *key = &ctx->key;
249 	struct rsa_edesc *edesc;
250 	gfp_t flags = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
251 		       GFP_KERNEL : GFP_ATOMIC;
252 	int sg_flags = (flags == GFP_ATOMIC) ? SG_MITER_ATOMIC : 0;
253 	int sec4_sg_index, sec4_sg_len = 0, sec4_sg_bytes;
254 	int src_nents, dst_nents;
255 	int mapped_src_nents, mapped_dst_nents;
256 	unsigned int diff_size = 0;
257 	int lzeros;
258 
259 	if (req->src_len > key->n_sz) {
260 		/*
261 		 * strip leading zeros and
262 		 * return the number of zeros to skip
263 		 */
264 		lzeros = caam_rsa_count_leading_zeros(req->src, req->src_len -
265 						      key->n_sz, sg_flags);
266 		if (lzeros < 0)
267 			return ERR_PTR(lzeros);
268 
269 		req_ctx->fixup_src = scatterwalk_ffwd(req_ctx->src, req->src,
270 						      lzeros);
271 		req_ctx->fixup_src_len = req->src_len - lzeros;
272 	} else {
273 		/*
274 		 * input src is less then n key modulus,
275 		 * so there will be zero padding
276 		 */
277 		diff_size = key->n_sz - req->src_len;
278 		req_ctx->fixup_src = req->src;
279 		req_ctx->fixup_src_len = req->src_len;
280 	}
281 
282 	src_nents = sg_nents_for_len(req_ctx->fixup_src,
283 				     req_ctx->fixup_src_len);
284 	dst_nents = sg_nents_for_len(req->dst, req->dst_len);
285 
286 	mapped_src_nents = dma_map_sg(dev, req_ctx->fixup_src, src_nents,
287 				      DMA_TO_DEVICE);
288 	if (unlikely(!mapped_src_nents)) {
289 		dev_err(dev, "unable to map source\n");
290 		return ERR_PTR(-ENOMEM);
291 	}
292 	mapped_dst_nents = dma_map_sg(dev, req->dst, dst_nents,
293 				      DMA_FROM_DEVICE);
294 	if (unlikely(!mapped_dst_nents)) {
295 		dev_err(dev, "unable to map destination\n");
296 		goto src_fail;
297 	}
298 
299 	if (!diff_size && mapped_src_nents == 1)
300 		sec4_sg_len = 0; /* no need for an input hw s/g table */
301 	else
302 		sec4_sg_len = mapped_src_nents + !!diff_size;
303 	sec4_sg_index = sec4_sg_len;
304 
305 	if (mapped_dst_nents > 1)
306 		sec4_sg_len += pad_sg_nents(mapped_dst_nents);
307 	else
308 		sec4_sg_len = pad_sg_nents(sec4_sg_len);
309 
310 	sec4_sg_bytes = sec4_sg_len * sizeof(struct sec4_sg_entry);
311 
312 	/* allocate space for base edesc, hw desc commands and link tables */
313 	edesc = kzalloc(sizeof(*edesc) + desclen + sec4_sg_bytes,
314 			GFP_DMA | flags);
315 	if (!edesc)
316 		goto dst_fail;
317 
318 	edesc->sec4_sg = (void *)edesc + sizeof(*edesc) + desclen;
319 	if (diff_size)
320 		dma_to_sec4_sg_one(edesc->sec4_sg, ctx->padding_dma, diff_size,
321 				   0);
322 
323 	if (sec4_sg_index)
324 		sg_to_sec4_sg_last(req_ctx->fixup_src, req_ctx->fixup_src_len,
325 				   edesc->sec4_sg + !!diff_size, 0);
326 
327 	if (mapped_dst_nents > 1)
328 		sg_to_sec4_sg_last(req->dst, req->dst_len,
329 				   edesc->sec4_sg + sec4_sg_index, 0);
330 
331 	/* Save nents for later use in Job Descriptor */
332 	edesc->src_nents = src_nents;
333 	edesc->dst_nents = dst_nents;
334 
335 	req_ctx->edesc = edesc;
336 
337 	if (!sec4_sg_bytes)
338 		return edesc;
339 
340 	edesc->mapped_src_nents = mapped_src_nents;
341 	edesc->mapped_dst_nents = mapped_dst_nents;
342 
343 	edesc->sec4_sg_dma = dma_map_single(dev, edesc->sec4_sg,
344 					    sec4_sg_bytes, DMA_TO_DEVICE);
345 	if (dma_mapping_error(dev, edesc->sec4_sg_dma)) {
346 		dev_err(dev, "unable to map S/G table\n");
347 		goto sec4_sg_fail;
348 	}
349 
350 	edesc->sec4_sg_bytes = sec4_sg_bytes;
351 
352 	print_hex_dump_debug("caampkc sec4_sg@" __stringify(__LINE__) ": ",
353 			     DUMP_PREFIX_ADDRESS, 16, 4, edesc->sec4_sg,
354 			     edesc->sec4_sg_bytes, 1);
355 
356 	return edesc;
357 
358 sec4_sg_fail:
359 	kfree(edesc);
360 dst_fail:
361 	dma_unmap_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
362 src_fail:
363 	dma_unmap_sg(dev, req_ctx->fixup_src, src_nents, DMA_TO_DEVICE);
364 	return ERR_PTR(-ENOMEM);
365 }
366 
367 static int akcipher_do_one_req(struct crypto_engine *engine, void *areq)
368 {
369 	struct akcipher_request *req = container_of(areq,
370 						    struct akcipher_request,
371 						    base);
372 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
373 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
374 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
375 	struct device *jrdev = ctx->dev;
376 	u32 *desc = req_ctx->edesc->hw_desc;
377 	int ret;
378 
379 	req_ctx->edesc->bklog = true;
380 
381 	ret = caam_jr_enqueue(jrdev, desc, req_ctx->akcipher_op_done, req);
382 
383 	if (ret == -ENOSPC && engine->retry_support)
384 		return ret;
385 
386 	if (ret != -EINPROGRESS) {
387 		rsa_pub_unmap(jrdev, req_ctx->edesc, req);
388 		rsa_io_unmap(jrdev, req_ctx->edesc, req);
389 		kfree(req_ctx->edesc);
390 	} else {
391 		ret = 0;
392 	}
393 
394 	return ret;
395 }
396 
397 static int set_rsa_pub_pdb(struct akcipher_request *req,
398 			   struct rsa_edesc *edesc)
399 {
400 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
401 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
402 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
403 	struct caam_rsa_key *key = &ctx->key;
404 	struct device *dev = ctx->dev;
405 	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
406 	int sec4_sg_index = 0;
407 
408 	pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
409 	if (dma_mapping_error(dev, pdb->n_dma)) {
410 		dev_err(dev, "Unable to map RSA modulus memory\n");
411 		return -ENOMEM;
412 	}
413 
414 	pdb->e_dma = dma_map_single(dev, key->e, key->e_sz, DMA_TO_DEVICE);
415 	if (dma_mapping_error(dev, pdb->e_dma)) {
416 		dev_err(dev, "Unable to map RSA public exponent memory\n");
417 		dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
418 		return -ENOMEM;
419 	}
420 
421 	if (edesc->mapped_src_nents > 1) {
422 		pdb->sgf |= RSA_PDB_SGF_F;
423 		pdb->f_dma = edesc->sec4_sg_dma;
424 		sec4_sg_index += edesc->mapped_src_nents;
425 	} else {
426 		pdb->f_dma = sg_dma_address(req_ctx->fixup_src);
427 	}
428 
429 	if (edesc->mapped_dst_nents > 1) {
430 		pdb->sgf |= RSA_PDB_SGF_G;
431 		pdb->g_dma = edesc->sec4_sg_dma +
432 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
433 	} else {
434 		pdb->g_dma = sg_dma_address(req->dst);
435 	}
436 
437 	pdb->sgf |= (key->e_sz << RSA_PDB_E_SHIFT) | key->n_sz;
438 	pdb->f_len = req_ctx->fixup_src_len;
439 
440 	return 0;
441 }
442 
443 static int set_rsa_priv_f1_pdb(struct akcipher_request *req,
444 			       struct rsa_edesc *edesc)
445 {
446 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
447 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
448 	struct caam_rsa_key *key = &ctx->key;
449 	struct device *dev = ctx->dev;
450 	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
451 	int sec4_sg_index = 0;
452 
453 	pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
454 	if (dma_mapping_error(dev, pdb->n_dma)) {
455 		dev_err(dev, "Unable to map modulus memory\n");
456 		return -ENOMEM;
457 	}
458 
459 	pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
460 	if (dma_mapping_error(dev, pdb->d_dma)) {
461 		dev_err(dev, "Unable to map RSA private exponent memory\n");
462 		dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
463 		return -ENOMEM;
464 	}
465 
466 	if (edesc->mapped_src_nents > 1) {
467 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
468 		pdb->g_dma = edesc->sec4_sg_dma;
469 		sec4_sg_index += edesc->mapped_src_nents;
470 
471 	} else {
472 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
473 
474 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
475 	}
476 
477 	if (edesc->mapped_dst_nents > 1) {
478 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
479 		pdb->f_dma = edesc->sec4_sg_dma +
480 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
481 	} else {
482 		pdb->f_dma = sg_dma_address(req->dst);
483 	}
484 
485 	pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
486 
487 	return 0;
488 }
489 
490 static int set_rsa_priv_f2_pdb(struct akcipher_request *req,
491 			       struct rsa_edesc *edesc)
492 {
493 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
494 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
495 	struct caam_rsa_key *key = &ctx->key;
496 	struct device *dev = ctx->dev;
497 	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
498 	int sec4_sg_index = 0;
499 	size_t p_sz = key->p_sz;
500 	size_t q_sz = key->q_sz;
501 
502 	pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
503 	if (dma_mapping_error(dev, pdb->d_dma)) {
504 		dev_err(dev, "Unable to map RSA private exponent memory\n");
505 		return -ENOMEM;
506 	}
507 
508 	pdb->p_dma = dma_map_single(dev, key->p, p_sz, DMA_TO_DEVICE);
509 	if (dma_mapping_error(dev, pdb->p_dma)) {
510 		dev_err(dev, "Unable to map RSA prime factor p memory\n");
511 		goto unmap_d;
512 	}
513 
514 	pdb->q_dma = dma_map_single(dev, key->q, q_sz, DMA_TO_DEVICE);
515 	if (dma_mapping_error(dev, pdb->q_dma)) {
516 		dev_err(dev, "Unable to map RSA prime factor q memory\n");
517 		goto unmap_p;
518 	}
519 
520 	pdb->tmp1_dma = dma_map_single(dev, key->tmp1, p_sz, DMA_BIDIRECTIONAL);
521 	if (dma_mapping_error(dev, pdb->tmp1_dma)) {
522 		dev_err(dev, "Unable to map RSA tmp1 memory\n");
523 		goto unmap_q;
524 	}
525 
526 	pdb->tmp2_dma = dma_map_single(dev, key->tmp2, q_sz, DMA_BIDIRECTIONAL);
527 	if (dma_mapping_error(dev, pdb->tmp2_dma)) {
528 		dev_err(dev, "Unable to map RSA tmp2 memory\n");
529 		goto unmap_tmp1;
530 	}
531 
532 	if (edesc->mapped_src_nents > 1) {
533 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
534 		pdb->g_dma = edesc->sec4_sg_dma;
535 		sec4_sg_index += edesc->mapped_src_nents;
536 	} else {
537 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
538 
539 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
540 	}
541 
542 	if (edesc->mapped_dst_nents > 1) {
543 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
544 		pdb->f_dma = edesc->sec4_sg_dma +
545 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
546 	} else {
547 		pdb->f_dma = sg_dma_address(req->dst);
548 	}
549 
550 	pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
551 	pdb->p_q_len = (q_sz << RSA_PDB_Q_SHIFT) | p_sz;
552 
553 	return 0;
554 
555 unmap_tmp1:
556 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
557 unmap_q:
558 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
559 unmap_p:
560 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
561 unmap_d:
562 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
563 
564 	return -ENOMEM;
565 }
566 
567 static int set_rsa_priv_f3_pdb(struct akcipher_request *req,
568 			       struct rsa_edesc *edesc)
569 {
570 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
571 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
572 	struct caam_rsa_key *key = &ctx->key;
573 	struct device *dev = ctx->dev;
574 	struct rsa_priv_f3_pdb *pdb = &edesc->pdb.priv_f3;
575 	int sec4_sg_index = 0;
576 	size_t p_sz = key->p_sz;
577 	size_t q_sz = key->q_sz;
578 
579 	pdb->p_dma = dma_map_single(dev, key->p, p_sz, DMA_TO_DEVICE);
580 	if (dma_mapping_error(dev, pdb->p_dma)) {
581 		dev_err(dev, "Unable to map RSA prime factor p memory\n");
582 		return -ENOMEM;
583 	}
584 
585 	pdb->q_dma = dma_map_single(dev, key->q, q_sz, DMA_TO_DEVICE);
586 	if (dma_mapping_error(dev, pdb->q_dma)) {
587 		dev_err(dev, "Unable to map RSA prime factor q memory\n");
588 		goto unmap_p;
589 	}
590 
591 	pdb->dp_dma = dma_map_single(dev, key->dp, p_sz, DMA_TO_DEVICE);
592 	if (dma_mapping_error(dev, pdb->dp_dma)) {
593 		dev_err(dev, "Unable to map RSA exponent dp memory\n");
594 		goto unmap_q;
595 	}
596 
597 	pdb->dq_dma = dma_map_single(dev, key->dq, q_sz, DMA_TO_DEVICE);
598 	if (dma_mapping_error(dev, pdb->dq_dma)) {
599 		dev_err(dev, "Unable to map RSA exponent dq memory\n");
600 		goto unmap_dp;
601 	}
602 
603 	pdb->c_dma = dma_map_single(dev, key->qinv, p_sz, DMA_TO_DEVICE);
604 	if (dma_mapping_error(dev, pdb->c_dma)) {
605 		dev_err(dev, "Unable to map RSA CRT coefficient qinv memory\n");
606 		goto unmap_dq;
607 	}
608 
609 	pdb->tmp1_dma = dma_map_single(dev, key->tmp1, p_sz, DMA_BIDIRECTIONAL);
610 	if (dma_mapping_error(dev, pdb->tmp1_dma)) {
611 		dev_err(dev, "Unable to map RSA tmp1 memory\n");
612 		goto unmap_qinv;
613 	}
614 
615 	pdb->tmp2_dma = dma_map_single(dev, key->tmp2, q_sz, DMA_BIDIRECTIONAL);
616 	if (dma_mapping_error(dev, pdb->tmp2_dma)) {
617 		dev_err(dev, "Unable to map RSA tmp2 memory\n");
618 		goto unmap_tmp1;
619 	}
620 
621 	if (edesc->mapped_src_nents > 1) {
622 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
623 		pdb->g_dma = edesc->sec4_sg_dma;
624 		sec4_sg_index += edesc->mapped_src_nents;
625 	} else {
626 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
627 
628 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
629 	}
630 
631 	if (edesc->mapped_dst_nents > 1) {
632 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
633 		pdb->f_dma = edesc->sec4_sg_dma +
634 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
635 	} else {
636 		pdb->f_dma = sg_dma_address(req->dst);
637 	}
638 
639 	pdb->sgf |= key->n_sz;
640 	pdb->p_q_len = (q_sz << RSA_PDB_Q_SHIFT) | p_sz;
641 
642 	return 0;
643 
644 unmap_tmp1:
645 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
646 unmap_qinv:
647 	dma_unmap_single(dev, pdb->c_dma, p_sz, DMA_TO_DEVICE);
648 unmap_dq:
649 	dma_unmap_single(dev, pdb->dq_dma, q_sz, DMA_TO_DEVICE);
650 unmap_dp:
651 	dma_unmap_single(dev, pdb->dp_dma, p_sz, DMA_TO_DEVICE);
652 unmap_q:
653 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
654 unmap_p:
655 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
656 
657 	return -ENOMEM;
658 }
659 
660 static int akcipher_enqueue_req(struct device *jrdev,
661 				void (*cbk)(struct device *jrdev, u32 *desc,
662 					    u32 err, void *context),
663 				struct akcipher_request *req)
664 {
665 	struct caam_drv_private_jr *jrpriv = dev_get_drvdata(jrdev);
666 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
667 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
668 	struct caam_rsa_key *key = &ctx->key;
669 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
670 	struct rsa_edesc *edesc = req_ctx->edesc;
671 	u32 *desc = edesc->hw_desc;
672 	int ret;
673 
674 	req_ctx->akcipher_op_done = cbk;
675 	/*
676 	 * Only the backlog request are sent to crypto-engine since the others
677 	 * can be handled by CAAM, if free, especially since JR has up to 1024
678 	 * entries (more than the 10 entries from crypto-engine).
679 	 */
680 	if (req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG)
681 		ret = crypto_transfer_akcipher_request_to_engine(jrpriv->engine,
682 								 req);
683 	else
684 		ret = caam_jr_enqueue(jrdev, desc, cbk, req);
685 
686 	if ((ret != -EINPROGRESS) && (ret != -EBUSY)) {
687 		switch (key->priv_form) {
688 		case FORM1:
689 			rsa_priv_f1_unmap(jrdev, edesc, req);
690 			break;
691 		case FORM2:
692 			rsa_priv_f2_unmap(jrdev, edesc, req);
693 			break;
694 		case FORM3:
695 			rsa_priv_f3_unmap(jrdev, edesc, req);
696 			break;
697 		default:
698 			rsa_pub_unmap(jrdev, edesc, req);
699 		}
700 		rsa_io_unmap(jrdev, edesc, req);
701 		kfree(edesc);
702 	}
703 
704 	return ret;
705 }
706 
707 static int caam_rsa_enc(struct akcipher_request *req)
708 {
709 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
710 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
711 	struct caam_rsa_key *key = &ctx->key;
712 	struct device *jrdev = ctx->dev;
713 	struct rsa_edesc *edesc;
714 	int ret;
715 
716 	if (unlikely(!key->n || !key->e))
717 		return -EINVAL;
718 
719 	if (req->dst_len < key->n_sz) {
720 		req->dst_len = key->n_sz;
721 		dev_err(jrdev, "Output buffer length less than parameter n\n");
722 		return -EOVERFLOW;
723 	}
724 
725 	/* Allocate extended descriptor */
726 	edesc = rsa_edesc_alloc(req, DESC_RSA_PUB_LEN);
727 	if (IS_ERR(edesc))
728 		return PTR_ERR(edesc);
729 
730 	/* Set RSA Encrypt Protocol Data Block */
731 	ret = set_rsa_pub_pdb(req, edesc);
732 	if (ret)
733 		goto init_fail;
734 
735 	/* Initialize Job Descriptor */
736 	init_rsa_pub_desc(edesc->hw_desc, &edesc->pdb.pub);
737 
738 	return akcipher_enqueue_req(jrdev, rsa_pub_done, req);
739 
740 init_fail:
741 	rsa_io_unmap(jrdev, edesc, req);
742 	kfree(edesc);
743 	return ret;
744 }
745 
746 static int caam_rsa_dec_priv_f1(struct akcipher_request *req)
747 {
748 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
749 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
750 	struct device *jrdev = ctx->dev;
751 	struct rsa_edesc *edesc;
752 	int ret;
753 
754 	/* Allocate extended descriptor */
755 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F1_LEN);
756 	if (IS_ERR(edesc))
757 		return PTR_ERR(edesc);
758 
759 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #1 */
760 	ret = set_rsa_priv_f1_pdb(req, edesc);
761 	if (ret)
762 		goto init_fail;
763 
764 	/* Initialize Job Descriptor */
765 	init_rsa_priv_f1_desc(edesc->hw_desc, &edesc->pdb.priv_f1);
766 
767 	return akcipher_enqueue_req(jrdev, rsa_priv_f_done, req);
768 
769 init_fail:
770 	rsa_io_unmap(jrdev, edesc, req);
771 	kfree(edesc);
772 	return ret;
773 }
774 
775 static int caam_rsa_dec_priv_f2(struct akcipher_request *req)
776 {
777 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
778 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
779 	struct device *jrdev = ctx->dev;
780 	struct rsa_edesc *edesc;
781 	int ret;
782 
783 	/* Allocate extended descriptor */
784 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F2_LEN);
785 	if (IS_ERR(edesc))
786 		return PTR_ERR(edesc);
787 
788 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #2 */
789 	ret = set_rsa_priv_f2_pdb(req, edesc);
790 	if (ret)
791 		goto init_fail;
792 
793 	/* Initialize Job Descriptor */
794 	init_rsa_priv_f2_desc(edesc->hw_desc, &edesc->pdb.priv_f2);
795 
796 	return akcipher_enqueue_req(jrdev, rsa_priv_f_done, req);
797 
798 init_fail:
799 	rsa_io_unmap(jrdev, edesc, req);
800 	kfree(edesc);
801 	return ret;
802 }
803 
804 static int caam_rsa_dec_priv_f3(struct akcipher_request *req)
805 {
806 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
807 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
808 	struct device *jrdev = ctx->dev;
809 	struct rsa_edesc *edesc;
810 	int ret;
811 
812 	/* Allocate extended descriptor */
813 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F3_LEN);
814 	if (IS_ERR(edesc))
815 		return PTR_ERR(edesc);
816 
817 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #3 */
818 	ret = set_rsa_priv_f3_pdb(req, edesc);
819 	if (ret)
820 		goto init_fail;
821 
822 	/* Initialize Job Descriptor */
823 	init_rsa_priv_f3_desc(edesc->hw_desc, &edesc->pdb.priv_f3);
824 
825 	return akcipher_enqueue_req(jrdev, rsa_priv_f_done, req);
826 
827 init_fail:
828 	rsa_io_unmap(jrdev, edesc, req);
829 	kfree(edesc);
830 	return ret;
831 }
832 
833 static int caam_rsa_dec(struct akcipher_request *req)
834 {
835 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
836 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
837 	struct caam_rsa_key *key = &ctx->key;
838 	int ret;
839 
840 	if (unlikely(!key->n || !key->d))
841 		return -EINVAL;
842 
843 	if (req->dst_len < key->n_sz) {
844 		req->dst_len = key->n_sz;
845 		dev_err(ctx->dev, "Output buffer length less than parameter n\n");
846 		return -EOVERFLOW;
847 	}
848 
849 	if (key->priv_form == FORM3)
850 		ret = caam_rsa_dec_priv_f3(req);
851 	else if (key->priv_form == FORM2)
852 		ret = caam_rsa_dec_priv_f2(req);
853 	else
854 		ret = caam_rsa_dec_priv_f1(req);
855 
856 	return ret;
857 }
858 
859 static void caam_rsa_free_key(struct caam_rsa_key *key)
860 {
861 	kfree_sensitive(key->d);
862 	kfree_sensitive(key->p);
863 	kfree_sensitive(key->q);
864 	kfree_sensitive(key->dp);
865 	kfree_sensitive(key->dq);
866 	kfree_sensitive(key->qinv);
867 	kfree_sensitive(key->tmp1);
868 	kfree_sensitive(key->tmp2);
869 	kfree(key->e);
870 	kfree(key->n);
871 	memset(key, 0, sizeof(*key));
872 }
873 
874 static void caam_rsa_drop_leading_zeros(const u8 **ptr, size_t *nbytes)
875 {
876 	while (!**ptr && *nbytes) {
877 		(*ptr)++;
878 		(*nbytes)--;
879 	}
880 }
881 
882 /**
883  * caam_read_rsa_crt - Used for reading dP, dQ, qInv CRT members.
884  * dP, dQ and qInv could decode to less than corresponding p, q length, as the
885  * BER-encoding requires that the minimum number of bytes be used to encode the
886  * integer. dP, dQ, qInv decoded values have to be zero-padded to appropriate
887  * length.
888  *
889  * @ptr   : pointer to {dP, dQ, qInv} CRT member
890  * @nbytes: length in bytes of {dP, dQ, qInv} CRT member
891  * @dstlen: length in bytes of corresponding p or q prime factor
892  */
893 static u8 *caam_read_rsa_crt(const u8 *ptr, size_t nbytes, size_t dstlen)
894 {
895 	u8 *dst;
896 
897 	caam_rsa_drop_leading_zeros(&ptr, &nbytes);
898 	if (!nbytes)
899 		return NULL;
900 
901 	dst = kzalloc(dstlen, GFP_DMA | GFP_KERNEL);
902 	if (!dst)
903 		return NULL;
904 
905 	memcpy(dst + (dstlen - nbytes), ptr, nbytes);
906 
907 	return dst;
908 }
909 
910 /**
911  * caam_read_raw_data - Read a raw byte stream as a positive integer.
912  * The function skips buffer's leading zeros, copies the remained data
913  * to a buffer allocated in the GFP_DMA | GFP_KERNEL zone and returns
914  * the address of the new buffer.
915  *
916  * @buf   : The data to read
917  * @nbytes: The amount of data to read
918  */
919 static inline u8 *caam_read_raw_data(const u8 *buf, size_t *nbytes)
920 {
921 
922 	caam_rsa_drop_leading_zeros(&buf, nbytes);
923 	if (!*nbytes)
924 		return NULL;
925 
926 	return kmemdup(buf, *nbytes, GFP_DMA | GFP_KERNEL);
927 }
928 
929 static int caam_rsa_check_key_length(unsigned int len)
930 {
931 	if (len > 4096)
932 		return -EINVAL;
933 	return 0;
934 }
935 
936 static int caam_rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key,
937 				unsigned int keylen)
938 {
939 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
940 	struct rsa_key raw_key = {NULL};
941 	struct caam_rsa_key *rsa_key = &ctx->key;
942 	int ret;
943 
944 	/* Free the old RSA key if any */
945 	caam_rsa_free_key(rsa_key);
946 
947 	ret = rsa_parse_pub_key(&raw_key, key, keylen);
948 	if (ret)
949 		return ret;
950 
951 	/* Copy key in DMA zone */
952 	rsa_key->e = kmemdup(raw_key.e, raw_key.e_sz, GFP_DMA | GFP_KERNEL);
953 	if (!rsa_key->e)
954 		goto err;
955 
956 	/*
957 	 * Skip leading zeros and copy the positive integer to a buffer
958 	 * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
959 	 * expects a positive integer for the RSA modulus and uses its length as
960 	 * decryption output length.
961 	 */
962 	rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
963 	if (!rsa_key->n)
964 		goto err;
965 
966 	if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
967 		caam_rsa_free_key(rsa_key);
968 		return -EINVAL;
969 	}
970 
971 	rsa_key->e_sz = raw_key.e_sz;
972 	rsa_key->n_sz = raw_key.n_sz;
973 
974 	return 0;
975 err:
976 	caam_rsa_free_key(rsa_key);
977 	return -ENOMEM;
978 }
979 
980 static void caam_rsa_set_priv_key_form(struct caam_rsa_ctx *ctx,
981 				       struct rsa_key *raw_key)
982 {
983 	struct caam_rsa_key *rsa_key = &ctx->key;
984 	size_t p_sz = raw_key->p_sz;
985 	size_t q_sz = raw_key->q_sz;
986 
987 	rsa_key->p = caam_read_raw_data(raw_key->p, &p_sz);
988 	if (!rsa_key->p)
989 		return;
990 	rsa_key->p_sz = p_sz;
991 
992 	rsa_key->q = caam_read_raw_data(raw_key->q, &q_sz);
993 	if (!rsa_key->q)
994 		goto free_p;
995 	rsa_key->q_sz = q_sz;
996 
997 	rsa_key->tmp1 = kzalloc(raw_key->p_sz, GFP_DMA | GFP_KERNEL);
998 	if (!rsa_key->tmp1)
999 		goto free_q;
1000 
1001 	rsa_key->tmp2 = kzalloc(raw_key->q_sz, GFP_DMA | GFP_KERNEL);
1002 	if (!rsa_key->tmp2)
1003 		goto free_tmp1;
1004 
1005 	rsa_key->priv_form = FORM2;
1006 
1007 	rsa_key->dp = caam_read_rsa_crt(raw_key->dp, raw_key->dp_sz, p_sz);
1008 	if (!rsa_key->dp)
1009 		goto free_tmp2;
1010 
1011 	rsa_key->dq = caam_read_rsa_crt(raw_key->dq, raw_key->dq_sz, q_sz);
1012 	if (!rsa_key->dq)
1013 		goto free_dp;
1014 
1015 	rsa_key->qinv = caam_read_rsa_crt(raw_key->qinv, raw_key->qinv_sz,
1016 					  q_sz);
1017 	if (!rsa_key->qinv)
1018 		goto free_dq;
1019 
1020 	rsa_key->priv_form = FORM3;
1021 
1022 	return;
1023 
1024 free_dq:
1025 	kfree_sensitive(rsa_key->dq);
1026 free_dp:
1027 	kfree_sensitive(rsa_key->dp);
1028 free_tmp2:
1029 	kfree_sensitive(rsa_key->tmp2);
1030 free_tmp1:
1031 	kfree_sensitive(rsa_key->tmp1);
1032 free_q:
1033 	kfree_sensitive(rsa_key->q);
1034 free_p:
1035 	kfree_sensitive(rsa_key->p);
1036 }
1037 
1038 static int caam_rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key,
1039 				 unsigned int keylen)
1040 {
1041 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
1042 	struct rsa_key raw_key = {NULL};
1043 	struct caam_rsa_key *rsa_key = &ctx->key;
1044 	int ret;
1045 
1046 	/* Free the old RSA key if any */
1047 	caam_rsa_free_key(rsa_key);
1048 
1049 	ret = rsa_parse_priv_key(&raw_key, key, keylen);
1050 	if (ret)
1051 		return ret;
1052 
1053 	/* Copy key in DMA zone */
1054 	rsa_key->d = kmemdup(raw_key.d, raw_key.d_sz, GFP_DMA | GFP_KERNEL);
1055 	if (!rsa_key->d)
1056 		goto err;
1057 
1058 	rsa_key->e = kmemdup(raw_key.e, raw_key.e_sz, GFP_DMA | GFP_KERNEL);
1059 	if (!rsa_key->e)
1060 		goto err;
1061 
1062 	/*
1063 	 * Skip leading zeros and copy the positive integer to a buffer
1064 	 * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
1065 	 * expects a positive integer for the RSA modulus and uses its length as
1066 	 * decryption output length.
1067 	 */
1068 	rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
1069 	if (!rsa_key->n)
1070 		goto err;
1071 
1072 	if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
1073 		caam_rsa_free_key(rsa_key);
1074 		return -EINVAL;
1075 	}
1076 
1077 	rsa_key->d_sz = raw_key.d_sz;
1078 	rsa_key->e_sz = raw_key.e_sz;
1079 	rsa_key->n_sz = raw_key.n_sz;
1080 
1081 	caam_rsa_set_priv_key_form(ctx, &raw_key);
1082 
1083 	return 0;
1084 
1085 err:
1086 	caam_rsa_free_key(rsa_key);
1087 	return -ENOMEM;
1088 }
1089 
1090 static unsigned int caam_rsa_max_size(struct crypto_akcipher *tfm)
1091 {
1092 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
1093 
1094 	return ctx->key.n_sz;
1095 }
1096 
1097 /* Per session pkc's driver context creation function */
1098 static int caam_rsa_init_tfm(struct crypto_akcipher *tfm)
1099 {
1100 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
1101 
1102 	ctx->dev = caam_jr_alloc();
1103 
1104 	if (IS_ERR(ctx->dev)) {
1105 		pr_err("Job Ring Device allocation for transform failed\n");
1106 		return PTR_ERR(ctx->dev);
1107 	}
1108 
1109 	ctx->padding_dma = dma_map_single(ctx->dev, zero_buffer,
1110 					  CAAM_RSA_MAX_INPUT_SIZE - 1,
1111 					  DMA_TO_DEVICE);
1112 	if (dma_mapping_error(ctx->dev, ctx->padding_dma)) {
1113 		dev_err(ctx->dev, "unable to map padding\n");
1114 		caam_jr_free(ctx->dev);
1115 		return -ENOMEM;
1116 	}
1117 
1118 	ctx->enginectx.op.do_one_request = akcipher_do_one_req;
1119 
1120 	return 0;
1121 }
1122 
1123 /* Per session pkc's driver context cleanup function */
1124 static void caam_rsa_exit_tfm(struct crypto_akcipher *tfm)
1125 {
1126 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
1127 	struct caam_rsa_key *key = &ctx->key;
1128 
1129 	dma_unmap_single(ctx->dev, ctx->padding_dma, CAAM_RSA_MAX_INPUT_SIZE -
1130 			 1, DMA_TO_DEVICE);
1131 	caam_rsa_free_key(key);
1132 	caam_jr_free(ctx->dev);
1133 }
1134 
1135 static struct caam_akcipher_alg caam_rsa = {
1136 	.akcipher = {
1137 		.encrypt = caam_rsa_enc,
1138 		.decrypt = caam_rsa_dec,
1139 		.set_pub_key = caam_rsa_set_pub_key,
1140 		.set_priv_key = caam_rsa_set_priv_key,
1141 		.max_size = caam_rsa_max_size,
1142 		.init = caam_rsa_init_tfm,
1143 		.exit = caam_rsa_exit_tfm,
1144 		.reqsize = sizeof(struct caam_rsa_req_ctx),
1145 		.base = {
1146 			.cra_name = "rsa",
1147 			.cra_driver_name = "rsa-caam",
1148 			.cra_priority = 3000,
1149 			.cra_module = THIS_MODULE,
1150 			.cra_ctxsize = sizeof(struct caam_rsa_ctx),
1151 		},
1152 	}
1153 };
1154 
1155 /* Public Key Cryptography module initialization handler */
1156 int caam_pkc_init(struct device *ctrldev)
1157 {
1158 	struct caam_drv_private *priv = dev_get_drvdata(ctrldev);
1159 	u32 pk_inst, pkha;
1160 	int err;
1161 	init_done = false;
1162 
1163 	/* Determine public key hardware accelerator presence. */
1164 	if (priv->era < 10) {
1165 		pk_inst = (rd_reg32(&priv->ctrl->perfmon.cha_num_ls) &
1166 			   CHA_ID_LS_PK_MASK) >> CHA_ID_LS_PK_SHIFT;
1167 	} else {
1168 		pkha = rd_reg32(&priv->ctrl->vreg.pkha);
1169 		pk_inst = pkha & CHA_VER_NUM_MASK;
1170 
1171 		/*
1172 		 * Newer CAAMs support partially disabled functionality. If this is the
1173 		 * case, the number is non-zero, but this bit is set to indicate that
1174 		 * no encryption or decryption is supported. Only signing and verifying
1175 		 * is supported.
1176 		 */
1177 		if (pkha & CHA_VER_MISC_PKHA_NO_CRYPT)
1178 			pk_inst = 0;
1179 	}
1180 
1181 	/* Do not register algorithms if PKHA is not present. */
1182 	if (!pk_inst)
1183 		return 0;
1184 
1185 	/* allocate zero buffer, used for padding input */
1186 	zero_buffer = kzalloc(CAAM_RSA_MAX_INPUT_SIZE - 1, GFP_DMA |
1187 			      GFP_KERNEL);
1188 	if (!zero_buffer)
1189 		return -ENOMEM;
1190 
1191 	err = crypto_register_akcipher(&caam_rsa.akcipher);
1192 
1193 	if (err) {
1194 		kfree(zero_buffer);
1195 		dev_warn(ctrldev, "%s alg registration failed\n",
1196 			 caam_rsa.akcipher.base.cra_driver_name);
1197 	} else {
1198 		init_done = true;
1199 		caam_rsa.registered = true;
1200 		dev_info(ctrldev, "caam pkc algorithms registered in /proc/crypto\n");
1201 	}
1202 
1203 	return err;
1204 }
1205 
1206 void caam_pkc_exit(void)
1207 {
1208 	if (!init_done)
1209 		return;
1210 
1211 	if (caam_rsa.registered)
1212 		crypto_unregister_akcipher(&caam_rsa.akcipher);
1213 
1214 	kfree(zero_buffer);
1215 }
1216