xref: /linux/drivers/crypto/caam/caampkc.c (revision 0e9ab8e4d44ae9d9aaf213bfd2c90bbe7289337b)
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 #include <linux/dma-mapping.h>
20 #include <linux/kernel.h>
21 
22 #define DESC_RSA_PUB_LEN	(2 * CAAM_CMD_SZ + SIZEOF_RSA_PUB_PDB)
23 #define DESC_RSA_PRIV_F1_LEN	(2 * CAAM_CMD_SZ + \
24 				 SIZEOF_RSA_PRIV_F1_PDB)
25 #define DESC_RSA_PRIV_F2_LEN	(2 * CAAM_CMD_SZ + \
26 				 SIZEOF_RSA_PRIV_F2_PDB)
27 #define DESC_RSA_PRIV_F3_LEN	(2 * CAAM_CMD_SZ + \
28 				 SIZEOF_RSA_PRIV_F3_PDB)
29 #define CAAM_RSA_MAX_INPUT_SIZE	512 /* for a 4096-bit modulus */
30 
31 /* buffer filled with zeros, used for padding */
32 static u8 *zero_buffer;
33 
34 /*
35  * variable used to avoid double free of resources in case
36  * algorithm registration was unsuccessful
37  */
38 static bool init_done;
39 
40 struct caam_akcipher_alg {
41 	struct akcipher_alg akcipher;
42 	bool registered;
43 };
44 
45 static void rsa_io_unmap(struct device *dev, struct rsa_edesc *edesc,
46 			 struct akcipher_request *req)
47 {
48 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
49 
50 	dma_unmap_sg(dev, req->dst, edesc->dst_nents, DMA_FROM_DEVICE);
51 	dma_unmap_sg(dev, req_ctx->fixup_src, edesc->src_nents, DMA_TO_DEVICE);
52 
53 	if (edesc->sec4_sg_bytes)
54 		dma_unmap_single(dev, edesc->sec4_sg_dma, edesc->sec4_sg_bytes,
55 				 DMA_TO_DEVICE);
56 }
57 
58 static void rsa_pub_unmap(struct device *dev, struct rsa_edesc *edesc,
59 			  struct akcipher_request *req)
60 {
61 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
62 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
63 	struct caam_rsa_key *key = &ctx->key;
64 	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
65 
66 	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
67 	dma_unmap_single(dev, pdb->e_dma, key->e_sz, DMA_TO_DEVICE);
68 }
69 
70 static void rsa_priv_f1_unmap(struct device *dev, struct rsa_edesc *edesc,
71 			      struct akcipher_request *req)
72 {
73 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
74 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
75 	struct caam_rsa_key *key = &ctx->key;
76 	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
77 
78 	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
79 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
80 }
81 
82 static void rsa_priv_f2_unmap(struct device *dev, struct rsa_edesc *edesc,
83 			      struct akcipher_request *req)
84 {
85 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
86 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
87 	struct caam_rsa_key *key = &ctx->key;
88 	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
89 	size_t p_sz = key->p_sz;
90 	size_t q_sz = key->q_sz;
91 
92 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
93 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
94 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
95 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
96 	dma_unmap_single(dev, pdb->tmp2_dma, q_sz, DMA_BIDIRECTIONAL);
97 }
98 
99 static void rsa_priv_f3_unmap(struct device *dev, struct rsa_edesc *edesc,
100 			      struct akcipher_request *req)
101 {
102 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
103 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
104 	struct caam_rsa_key *key = &ctx->key;
105 	struct rsa_priv_f3_pdb *pdb = &edesc->pdb.priv_f3;
106 	size_t p_sz = key->p_sz;
107 	size_t q_sz = key->q_sz;
108 
109 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
110 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
111 	dma_unmap_single(dev, pdb->dp_dma, p_sz, DMA_TO_DEVICE);
112 	dma_unmap_single(dev, pdb->dq_dma, q_sz, DMA_TO_DEVICE);
113 	dma_unmap_single(dev, pdb->c_dma, p_sz, DMA_TO_DEVICE);
114 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
115 	dma_unmap_single(dev, pdb->tmp2_dma, q_sz, DMA_BIDIRECTIONAL);
116 }
117 
118 /* RSA Job Completion handler */
119 static void rsa_pub_done(struct device *dev, u32 *desc, u32 err, void *context)
120 {
121 	struct akcipher_request *req = context;
122 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
123 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
124 	struct rsa_edesc *edesc;
125 	int ecode = 0;
126 	bool has_bklog;
127 
128 	if (err)
129 		ecode = caam_jr_strstatus(dev, err);
130 
131 	edesc = req_ctx->edesc;
132 	has_bklog = edesc->bklog;
133 
134 	rsa_pub_unmap(dev, edesc, req);
135 	rsa_io_unmap(dev, edesc, req);
136 	kfree(edesc);
137 
138 	/*
139 	 * If no backlog flag, the completion of the request is done
140 	 * by CAAM, not crypto engine.
141 	 */
142 	if (!has_bklog)
143 		akcipher_request_complete(req, ecode);
144 	else
145 		crypto_finalize_akcipher_request(jrp->engine, req, ecode);
146 }
147 
148 static void rsa_priv_f_done(struct device *dev, u32 *desc, u32 err,
149 			    void *context)
150 {
151 	struct akcipher_request *req = context;
152 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
153 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
154 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
155 	struct caam_rsa_key *key = &ctx->key;
156 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
157 	struct rsa_edesc *edesc;
158 	int ecode = 0;
159 	bool has_bklog;
160 
161 	if (err)
162 		ecode = caam_jr_strstatus(dev, err);
163 
164 	edesc = req_ctx->edesc;
165 	has_bklog = edesc->bklog;
166 
167 	switch (key->priv_form) {
168 	case FORM1:
169 		rsa_priv_f1_unmap(dev, edesc, req);
170 		break;
171 	case FORM2:
172 		rsa_priv_f2_unmap(dev, edesc, req);
173 		break;
174 	case FORM3:
175 		rsa_priv_f3_unmap(dev, edesc, req);
176 	}
177 
178 	rsa_io_unmap(dev, edesc, req);
179 	kfree(edesc);
180 
181 	/*
182 	 * If no backlog flag, the completion of the request is done
183 	 * by CAAM, not crypto engine.
184 	 */
185 	if (!has_bklog)
186 		akcipher_request_complete(req, ecode);
187 	else
188 		crypto_finalize_akcipher_request(jrp->engine, req, ecode);
189 }
190 
191 /**
192  * caam_rsa_count_leading_zeros - Count leading zeros, need it to strip,
193  *                                from a given scatterlist
194  *
195  * @sgl   : scatterlist to count zeros from
196  * @nbytes: number of zeros, in bytes, to strip
197  * @flags : operation flags
198  */
199 static int caam_rsa_count_leading_zeros(struct scatterlist *sgl,
200 					unsigned int nbytes,
201 					unsigned int flags)
202 {
203 	struct sg_mapping_iter miter;
204 	int lzeros, ents;
205 	unsigned int len;
206 	unsigned int tbytes = nbytes;
207 	const u8 *buff;
208 
209 	ents = sg_nents_for_len(sgl, nbytes);
210 	if (ents < 0)
211 		return ents;
212 
213 	sg_miter_start(&miter, sgl, ents, SG_MITER_FROM_SG | flags);
214 
215 	lzeros = 0;
216 	len = 0;
217 	while (nbytes > 0) {
218 		/* do not strip more than given bytes */
219 		while (len && !*buff && lzeros < nbytes) {
220 			lzeros++;
221 			len--;
222 			buff++;
223 		}
224 
225 		if (len && *buff)
226 			break;
227 
228 		sg_miter_next(&miter);
229 		buff = miter.addr;
230 		len = miter.length;
231 
232 		nbytes -= lzeros;
233 		lzeros = 0;
234 	}
235 
236 	miter.consumed = lzeros;
237 	sg_miter_stop(&miter);
238 	nbytes -= lzeros;
239 
240 	return tbytes - nbytes;
241 }
242 
243 static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req,
244 					 size_t desclen)
245 {
246 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
247 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
248 	struct device *dev = ctx->dev;
249 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
250 	struct caam_rsa_key *key = &ctx->key;
251 	struct rsa_edesc *edesc;
252 	gfp_t flags = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
253 		       GFP_KERNEL : GFP_ATOMIC;
254 	int sg_flags = (flags == GFP_ATOMIC) ? SG_MITER_ATOMIC : 0;
255 	int sec4_sg_index, sec4_sg_len = 0, sec4_sg_bytes;
256 	int src_nents, dst_nents;
257 	int mapped_src_nents, mapped_dst_nents;
258 	unsigned int diff_size = 0;
259 	int lzeros;
260 
261 	if (req->src_len > key->n_sz) {
262 		/*
263 		 * strip leading zeros and
264 		 * return the number of zeros to skip
265 		 */
266 		lzeros = caam_rsa_count_leading_zeros(req->src, req->src_len -
267 						      key->n_sz, sg_flags);
268 		if (lzeros < 0)
269 			return ERR_PTR(lzeros);
270 
271 		req_ctx->fixup_src = scatterwalk_ffwd(req_ctx->src, req->src,
272 						      lzeros);
273 		req_ctx->fixup_src_len = req->src_len - lzeros;
274 	} else {
275 		/*
276 		 * input src is less then n key modulus,
277 		 * so there will be zero padding
278 		 */
279 		diff_size = key->n_sz - req->src_len;
280 		req_ctx->fixup_src = req->src;
281 		req_ctx->fixup_src_len = req->src_len;
282 	}
283 
284 	src_nents = sg_nents_for_len(req_ctx->fixup_src,
285 				     req_ctx->fixup_src_len);
286 	dst_nents = sg_nents_for_len(req->dst, req->dst_len);
287 
288 	mapped_src_nents = dma_map_sg(dev, req_ctx->fixup_src, src_nents,
289 				      DMA_TO_DEVICE);
290 	if (unlikely(!mapped_src_nents)) {
291 		dev_err(dev, "unable to map source\n");
292 		return ERR_PTR(-ENOMEM);
293 	}
294 	mapped_dst_nents = dma_map_sg(dev, req->dst, dst_nents,
295 				      DMA_FROM_DEVICE);
296 	if (unlikely(!mapped_dst_nents)) {
297 		dev_err(dev, "unable to map destination\n");
298 		goto src_fail;
299 	}
300 
301 	if (!diff_size && mapped_src_nents == 1)
302 		sec4_sg_len = 0; /* no need for an input hw s/g table */
303 	else
304 		sec4_sg_len = mapped_src_nents + !!diff_size;
305 	sec4_sg_index = sec4_sg_len;
306 
307 	if (mapped_dst_nents > 1)
308 		sec4_sg_len += pad_sg_nents(mapped_dst_nents);
309 	else
310 		sec4_sg_len = pad_sg_nents(sec4_sg_len);
311 
312 	sec4_sg_bytes = sec4_sg_len * sizeof(struct sec4_sg_entry);
313 
314 	/* allocate space for base edesc, hw desc commands and link tables */
315 	edesc = kzalloc(sizeof(*edesc) + desclen + sec4_sg_bytes, flags);
316 	if (!edesc)
317 		goto dst_fail;
318 
319 	edesc->sec4_sg = (void *)edesc + sizeof(*edesc) + desclen;
320 	if (diff_size)
321 		dma_to_sec4_sg_one(edesc->sec4_sg, ctx->padding_dma, diff_size,
322 				   0);
323 
324 	if (sec4_sg_index)
325 		sg_to_sec4_sg_last(req_ctx->fixup_src, req_ctx->fixup_src_len,
326 				   edesc->sec4_sg + !!diff_size, 0);
327 
328 	if (mapped_dst_nents > 1)
329 		sg_to_sec4_sg_last(req->dst, req->dst_len,
330 				   edesc->sec4_sg + sec4_sg_index, 0);
331 
332 	/* Save nents for later use in Job Descriptor */
333 	edesc->src_nents = src_nents;
334 	edesc->dst_nents = dst_nents;
335 
336 	req_ctx->edesc = edesc;
337 
338 	if (!sec4_sg_bytes)
339 		return edesc;
340 
341 	edesc->mapped_src_nents = mapped_src_nents;
342 	edesc->mapped_dst_nents = mapped_dst_nents;
343 
344 	edesc->sec4_sg_dma = dma_map_single(dev, edesc->sec4_sg,
345 					    sec4_sg_bytes, DMA_TO_DEVICE);
346 	if (dma_mapping_error(dev, edesc->sec4_sg_dma)) {
347 		dev_err(dev, "unable to map S/G table\n");
348 		goto sec4_sg_fail;
349 	}
350 
351 	edesc->sec4_sg_bytes = sec4_sg_bytes;
352 
353 	print_hex_dump_debug("caampkc sec4_sg@" __stringify(__LINE__) ": ",
354 			     DUMP_PREFIX_ADDRESS, 16, 4, edesc->sec4_sg,
355 			     edesc->sec4_sg_bytes, 1);
356 
357 	return edesc;
358 
359 sec4_sg_fail:
360 	kfree(edesc);
361 dst_fail:
362 	dma_unmap_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
363 src_fail:
364 	dma_unmap_sg(dev, req_ctx->fixup_src, src_nents, DMA_TO_DEVICE);
365 	return ERR_PTR(-ENOMEM);
366 }
367 
368 static int akcipher_do_one_req(struct crypto_engine *engine, void *areq)
369 {
370 	struct akcipher_request *req = container_of(areq,
371 						    struct akcipher_request,
372 						    base);
373 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
374 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
375 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
376 	struct device *jrdev = ctx->dev;
377 	u32 *desc = req_ctx->edesc->hw_desc;
378 	int ret;
379 
380 	req_ctx->edesc->bklog = true;
381 
382 	ret = caam_jr_enqueue(jrdev, desc, req_ctx->akcipher_op_done, req);
383 
384 	if (ret == -ENOSPC && engine->retry_support)
385 		return ret;
386 
387 	if (ret != -EINPROGRESS) {
388 		rsa_pub_unmap(jrdev, req_ctx->edesc, req);
389 		rsa_io_unmap(jrdev, req_ctx->edesc, req);
390 		kfree(req_ctx->edesc);
391 	} else {
392 		ret = 0;
393 	}
394 
395 	return ret;
396 }
397 
398 static int set_rsa_pub_pdb(struct akcipher_request *req,
399 			   struct rsa_edesc *edesc)
400 {
401 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
402 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
403 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
404 	struct caam_rsa_key *key = &ctx->key;
405 	struct device *dev = ctx->dev;
406 	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
407 	int sec4_sg_index = 0;
408 
409 	pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
410 	if (dma_mapping_error(dev, pdb->n_dma)) {
411 		dev_err(dev, "Unable to map RSA modulus memory\n");
412 		return -ENOMEM;
413 	}
414 
415 	pdb->e_dma = dma_map_single(dev, key->e, key->e_sz, DMA_TO_DEVICE);
416 	if (dma_mapping_error(dev, pdb->e_dma)) {
417 		dev_err(dev, "Unable to map RSA public exponent memory\n");
418 		dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
419 		return -ENOMEM;
420 	}
421 
422 	if (edesc->mapped_src_nents > 1) {
423 		pdb->sgf |= RSA_PDB_SGF_F;
424 		pdb->f_dma = edesc->sec4_sg_dma;
425 		sec4_sg_index += edesc->mapped_src_nents;
426 	} else {
427 		pdb->f_dma = sg_dma_address(req_ctx->fixup_src);
428 	}
429 
430 	if (edesc->mapped_dst_nents > 1) {
431 		pdb->sgf |= RSA_PDB_SGF_G;
432 		pdb->g_dma = edesc->sec4_sg_dma +
433 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
434 	} else {
435 		pdb->g_dma = sg_dma_address(req->dst);
436 	}
437 
438 	pdb->sgf |= (key->e_sz << RSA_PDB_E_SHIFT) | key->n_sz;
439 	pdb->f_len = req_ctx->fixup_src_len;
440 
441 	return 0;
442 }
443 
444 static int set_rsa_priv_f1_pdb(struct akcipher_request *req,
445 			       struct rsa_edesc *edesc)
446 {
447 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
448 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
449 	struct caam_rsa_key *key = &ctx->key;
450 	struct device *dev = ctx->dev;
451 	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
452 	int sec4_sg_index = 0;
453 
454 	pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
455 	if (dma_mapping_error(dev, pdb->n_dma)) {
456 		dev_err(dev, "Unable to map modulus memory\n");
457 		return -ENOMEM;
458 	}
459 
460 	pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
461 	if (dma_mapping_error(dev, pdb->d_dma)) {
462 		dev_err(dev, "Unable to map RSA private exponent memory\n");
463 		dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
464 		return -ENOMEM;
465 	}
466 
467 	if (edesc->mapped_src_nents > 1) {
468 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
469 		pdb->g_dma = edesc->sec4_sg_dma;
470 		sec4_sg_index += edesc->mapped_src_nents;
471 
472 	} else {
473 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
474 
475 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
476 	}
477 
478 	if (edesc->mapped_dst_nents > 1) {
479 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
480 		pdb->f_dma = edesc->sec4_sg_dma +
481 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
482 	} else {
483 		pdb->f_dma = sg_dma_address(req->dst);
484 	}
485 
486 	pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
487 
488 	return 0;
489 }
490 
491 static int set_rsa_priv_f2_pdb(struct akcipher_request *req,
492 			       struct rsa_edesc *edesc)
493 {
494 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
495 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
496 	struct caam_rsa_key *key = &ctx->key;
497 	struct device *dev = ctx->dev;
498 	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
499 	int sec4_sg_index = 0;
500 	size_t p_sz = key->p_sz;
501 	size_t q_sz = key->q_sz;
502 
503 	pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
504 	if (dma_mapping_error(dev, pdb->d_dma)) {
505 		dev_err(dev, "Unable to map RSA private exponent memory\n");
506 		return -ENOMEM;
507 	}
508 
509 	pdb->p_dma = dma_map_single(dev, key->p, p_sz, DMA_TO_DEVICE);
510 	if (dma_mapping_error(dev, pdb->p_dma)) {
511 		dev_err(dev, "Unable to map RSA prime factor p memory\n");
512 		goto unmap_d;
513 	}
514 
515 	pdb->q_dma = dma_map_single(dev, key->q, q_sz, DMA_TO_DEVICE);
516 	if (dma_mapping_error(dev, pdb->q_dma)) {
517 		dev_err(dev, "Unable to map RSA prime factor q memory\n");
518 		goto unmap_p;
519 	}
520 
521 	pdb->tmp1_dma = dma_map_single(dev, key->tmp1, p_sz, DMA_BIDIRECTIONAL);
522 	if (dma_mapping_error(dev, pdb->tmp1_dma)) {
523 		dev_err(dev, "Unable to map RSA tmp1 memory\n");
524 		goto unmap_q;
525 	}
526 
527 	pdb->tmp2_dma = dma_map_single(dev, key->tmp2, q_sz, DMA_BIDIRECTIONAL);
528 	if (dma_mapping_error(dev, pdb->tmp2_dma)) {
529 		dev_err(dev, "Unable to map RSA tmp2 memory\n");
530 		goto unmap_tmp1;
531 	}
532 
533 	if (edesc->mapped_src_nents > 1) {
534 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
535 		pdb->g_dma = edesc->sec4_sg_dma;
536 		sec4_sg_index += edesc->mapped_src_nents;
537 	} else {
538 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
539 
540 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
541 	}
542 
543 	if (edesc->mapped_dst_nents > 1) {
544 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
545 		pdb->f_dma = edesc->sec4_sg_dma +
546 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
547 	} else {
548 		pdb->f_dma = sg_dma_address(req->dst);
549 	}
550 
551 	pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
552 	pdb->p_q_len = (q_sz << RSA_PDB_Q_SHIFT) | p_sz;
553 
554 	return 0;
555 
556 unmap_tmp1:
557 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
558 unmap_q:
559 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
560 unmap_p:
561 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
562 unmap_d:
563 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
564 
565 	return -ENOMEM;
566 }
567 
568 static int set_rsa_priv_f3_pdb(struct akcipher_request *req,
569 			       struct rsa_edesc *edesc)
570 {
571 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
572 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
573 	struct caam_rsa_key *key = &ctx->key;
574 	struct device *dev = ctx->dev;
575 	struct rsa_priv_f3_pdb *pdb = &edesc->pdb.priv_f3;
576 	int sec4_sg_index = 0;
577 	size_t p_sz = key->p_sz;
578 	size_t q_sz = key->q_sz;
579 
580 	pdb->p_dma = dma_map_single(dev, key->p, p_sz, DMA_TO_DEVICE);
581 	if (dma_mapping_error(dev, pdb->p_dma)) {
582 		dev_err(dev, "Unable to map RSA prime factor p memory\n");
583 		return -ENOMEM;
584 	}
585 
586 	pdb->q_dma = dma_map_single(dev, key->q, q_sz, DMA_TO_DEVICE);
587 	if (dma_mapping_error(dev, pdb->q_dma)) {
588 		dev_err(dev, "Unable to map RSA prime factor q memory\n");
589 		goto unmap_p;
590 	}
591 
592 	pdb->dp_dma = dma_map_single(dev, key->dp, p_sz, DMA_TO_DEVICE);
593 	if (dma_mapping_error(dev, pdb->dp_dma)) {
594 		dev_err(dev, "Unable to map RSA exponent dp memory\n");
595 		goto unmap_q;
596 	}
597 
598 	pdb->dq_dma = dma_map_single(dev, key->dq, q_sz, DMA_TO_DEVICE);
599 	if (dma_mapping_error(dev, pdb->dq_dma)) {
600 		dev_err(dev, "Unable to map RSA exponent dq memory\n");
601 		goto unmap_dp;
602 	}
603 
604 	pdb->c_dma = dma_map_single(dev, key->qinv, p_sz, DMA_TO_DEVICE);
605 	if (dma_mapping_error(dev, pdb->c_dma)) {
606 		dev_err(dev, "Unable to map RSA CRT coefficient qinv memory\n");
607 		goto unmap_dq;
608 	}
609 
610 	pdb->tmp1_dma = dma_map_single(dev, key->tmp1, p_sz, DMA_BIDIRECTIONAL);
611 	if (dma_mapping_error(dev, pdb->tmp1_dma)) {
612 		dev_err(dev, "Unable to map RSA tmp1 memory\n");
613 		goto unmap_qinv;
614 	}
615 
616 	pdb->tmp2_dma = dma_map_single(dev, key->tmp2, q_sz, DMA_BIDIRECTIONAL);
617 	if (dma_mapping_error(dev, pdb->tmp2_dma)) {
618 		dev_err(dev, "Unable to map RSA tmp2 memory\n");
619 		goto unmap_tmp1;
620 	}
621 
622 	if (edesc->mapped_src_nents > 1) {
623 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
624 		pdb->g_dma = edesc->sec4_sg_dma;
625 		sec4_sg_index += edesc->mapped_src_nents;
626 	} else {
627 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
628 
629 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
630 	}
631 
632 	if (edesc->mapped_dst_nents > 1) {
633 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
634 		pdb->f_dma = edesc->sec4_sg_dma +
635 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
636 	} else {
637 		pdb->f_dma = sg_dma_address(req->dst);
638 	}
639 
640 	pdb->sgf |= key->n_sz;
641 	pdb->p_q_len = (q_sz << RSA_PDB_Q_SHIFT) | p_sz;
642 
643 	return 0;
644 
645 unmap_tmp1:
646 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
647 unmap_qinv:
648 	dma_unmap_single(dev, pdb->c_dma, p_sz, DMA_TO_DEVICE);
649 unmap_dq:
650 	dma_unmap_single(dev, pdb->dq_dma, q_sz, DMA_TO_DEVICE);
651 unmap_dp:
652 	dma_unmap_single(dev, pdb->dp_dma, p_sz, DMA_TO_DEVICE);
653 unmap_q:
654 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
655 unmap_p:
656 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
657 
658 	return -ENOMEM;
659 }
660 
661 static int akcipher_enqueue_req(struct device *jrdev,
662 				void (*cbk)(struct device *jrdev, u32 *desc,
663 					    u32 err, void *context),
664 				struct akcipher_request *req)
665 {
666 	struct caam_drv_private_jr *jrpriv = dev_get_drvdata(jrdev);
667 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
668 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
669 	struct caam_rsa_key *key = &ctx->key;
670 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
671 	struct rsa_edesc *edesc = req_ctx->edesc;
672 	u32 *desc = edesc->hw_desc;
673 	int ret;
674 
675 	req_ctx->akcipher_op_done = cbk;
676 	/*
677 	 * Only the backlog request are sent to crypto-engine since the others
678 	 * can be handled by CAAM, if free, especially since JR has up to 1024
679 	 * entries (more than the 10 entries from crypto-engine).
680 	 */
681 	if (req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG)
682 		ret = crypto_transfer_akcipher_request_to_engine(jrpriv->engine,
683 								 req);
684 	else
685 		ret = caam_jr_enqueue(jrdev, desc, cbk, req);
686 
687 	if ((ret != -EINPROGRESS) && (ret != -EBUSY)) {
688 		switch (key->priv_form) {
689 		case FORM1:
690 			rsa_priv_f1_unmap(jrdev, edesc, req);
691 			break;
692 		case FORM2:
693 			rsa_priv_f2_unmap(jrdev, edesc, req);
694 			break;
695 		case FORM3:
696 			rsa_priv_f3_unmap(jrdev, edesc, req);
697 			break;
698 		default:
699 			rsa_pub_unmap(jrdev, edesc, req);
700 		}
701 		rsa_io_unmap(jrdev, edesc, req);
702 		kfree(edesc);
703 	}
704 
705 	return ret;
706 }
707 
708 static int caam_rsa_enc(struct akcipher_request *req)
709 {
710 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
711 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
712 	struct caam_rsa_key *key = &ctx->key;
713 	struct device *jrdev = ctx->dev;
714 	struct rsa_edesc *edesc;
715 	int ret;
716 
717 	if (unlikely(!key->n || !key->e))
718 		return -EINVAL;
719 
720 	if (req->dst_len < key->n_sz) {
721 		req->dst_len = key->n_sz;
722 		dev_err(jrdev, "Output buffer length less than parameter n\n");
723 		return -EOVERFLOW;
724 	}
725 
726 	/* Allocate extended descriptor */
727 	edesc = rsa_edesc_alloc(req, DESC_RSA_PUB_LEN);
728 	if (IS_ERR(edesc))
729 		return PTR_ERR(edesc);
730 
731 	/* Set RSA Encrypt Protocol Data Block */
732 	ret = set_rsa_pub_pdb(req, edesc);
733 	if (ret)
734 		goto init_fail;
735 
736 	/* Initialize Job Descriptor */
737 	init_rsa_pub_desc(edesc->hw_desc, &edesc->pdb.pub);
738 
739 	return akcipher_enqueue_req(jrdev, rsa_pub_done, req);
740 
741 init_fail:
742 	rsa_io_unmap(jrdev, edesc, req);
743 	kfree(edesc);
744 	return ret;
745 }
746 
747 static int caam_rsa_dec_priv_f1(struct akcipher_request *req)
748 {
749 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
750 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
751 	struct device *jrdev = ctx->dev;
752 	struct rsa_edesc *edesc;
753 	int ret;
754 
755 	/* Allocate extended descriptor */
756 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F1_LEN);
757 	if (IS_ERR(edesc))
758 		return PTR_ERR(edesc);
759 
760 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #1 */
761 	ret = set_rsa_priv_f1_pdb(req, edesc);
762 	if (ret)
763 		goto init_fail;
764 
765 	/* Initialize Job Descriptor */
766 	init_rsa_priv_f1_desc(edesc->hw_desc, &edesc->pdb.priv_f1);
767 
768 	return akcipher_enqueue_req(jrdev, rsa_priv_f_done, req);
769 
770 init_fail:
771 	rsa_io_unmap(jrdev, edesc, req);
772 	kfree(edesc);
773 	return ret;
774 }
775 
776 static int caam_rsa_dec_priv_f2(struct akcipher_request *req)
777 {
778 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
779 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
780 	struct device *jrdev = ctx->dev;
781 	struct rsa_edesc *edesc;
782 	int ret;
783 
784 	/* Allocate extended descriptor */
785 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F2_LEN);
786 	if (IS_ERR(edesc))
787 		return PTR_ERR(edesc);
788 
789 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #2 */
790 	ret = set_rsa_priv_f2_pdb(req, edesc);
791 	if (ret)
792 		goto init_fail;
793 
794 	/* Initialize Job Descriptor */
795 	init_rsa_priv_f2_desc(edesc->hw_desc, &edesc->pdb.priv_f2);
796 
797 	return akcipher_enqueue_req(jrdev, rsa_priv_f_done, req);
798 
799 init_fail:
800 	rsa_io_unmap(jrdev, edesc, req);
801 	kfree(edesc);
802 	return ret;
803 }
804 
805 static int caam_rsa_dec_priv_f3(struct akcipher_request *req)
806 {
807 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
808 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
809 	struct device *jrdev = ctx->dev;
810 	struct rsa_edesc *edesc;
811 	int ret;
812 
813 	/* Allocate extended descriptor */
814 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F3_LEN);
815 	if (IS_ERR(edesc))
816 		return PTR_ERR(edesc);
817 
818 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #3 */
819 	ret = set_rsa_priv_f3_pdb(req, edesc);
820 	if (ret)
821 		goto init_fail;
822 
823 	/* Initialize Job Descriptor */
824 	init_rsa_priv_f3_desc(edesc->hw_desc, &edesc->pdb.priv_f3);
825 
826 	return akcipher_enqueue_req(jrdev, rsa_priv_f_done, req);
827 
828 init_fail:
829 	rsa_io_unmap(jrdev, edesc, req);
830 	kfree(edesc);
831 	return ret;
832 }
833 
834 static int caam_rsa_dec(struct akcipher_request *req)
835 {
836 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
837 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
838 	struct caam_rsa_key *key = &ctx->key;
839 	int ret;
840 
841 	if (unlikely(!key->n || !key->d))
842 		return -EINVAL;
843 
844 	if (req->dst_len < key->n_sz) {
845 		req->dst_len = key->n_sz;
846 		dev_err(ctx->dev, "Output buffer length less than parameter n\n");
847 		return -EOVERFLOW;
848 	}
849 
850 	if (key->priv_form == FORM3)
851 		ret = caam_rsa_dec_priv_f3(req);
852 	else if (key->priv_form == FORM2)
853 		ret = caam_rsa_dec_priv_f2(req);
854 	else
855 		ret = caam_rsa_dec_priv_f1(req);
856 
857 	return ret;
858 }
859 
860 static void caam_rsa_free_key(struct caam_rsa_key *key)
861 {
862 	kfree_sensitive(key->d);
863 	kfree_sensitive(key->p);
864 	kfree_sensitive(key->q);
865 	kfree_sensitive(key->dp);
866 	kfree_sensitive(key->dq);
867 	kfree_sensitive(key->qinv);
868 	kfree_sensitive(key->tmp1);
869 	kfree_sensitive(key->tmp2);
870 	kfree(key->e);
871 	kfree(key->n);
872 	memset(key, 0, sizeof(*key));
873 }
874 
875 static void caam_rsa_drop_leading_zeros(const u8 **ptr, size_t *nbytes)
876 {
877 	while (!**ptr && *nbytes) {
878 		(*ptr)++;
879 		(*nbytes)--;
880 	}
881 }
882 
883 /**
884  * caam_read_rsa_crt - Used for reading dP, dQ, qInv CRT members.
885  * dP, dQ and qInv could decode to less than corresponding p, q length, as the
886  * BER-encoding requires that the minimum number of bytes be used to encode the
887  * integer. dP, dQ, qInv decoded values have to be zero-padded to appropriate
888  * length.
889  *
890  * @ptr   : pointer to {dP, dQ, qInv} CRT member
891  * @nbytes: length in bytes of {dP, dQ, qInv} CRT member
892  * @dstlen: length in bytes of corresponding p or q prime factor
893  */
894 static u8 *caam_read_rsa_crt(const u8 *ptr, size_t nbytes, size_t dstlen)
895 {
896 	u8 *dst;
897 
898 	caam_rsa_drop_leading_zeros(&ptr, &nbytes);
899 	if (!nbytes)
900 		return NULL;
901 
902 	dst = kzalloc(dstlen, GFP_KERNEL);
903 	if (!dst)
904 		return NULL;
905 
906 	memcpy(dst + (dstlen - nbytes), ptr, nbytes);
907 
908 	return dst;
909 }
910 
911 /**
912  * caam_read_raw_data - Read a raw byte stream as a positive integer.
913  * The function skips buffer's leading zeros, copies the remained data
914  * to a buffer allocated in the GFP_KERNEL zone and returns
915  * the address of the new buffer.
916  *
917  * @buf   : The data to read
918  * @nbytes: The amount of data to read
919  */
920 static inline u8 *caam_read_raw_data(const u8 *buf, size_t *nbytes)
921 {
922 
923 	caam_rsa_drop_leading_zeros(&buf, nbytes);
924 	if (!*nbytes)
925 		return NULL;
926 
927 	return kmemdup(buf, *nbytes, GFP_KERNEL);
928 }
929 
930 static int caam_rsa_check_key_length(unsigned int len)
931 {
932 	if (len > 4096)
933 		return -EINVAL;
934 	return 0;
935 }
936 
937 static int caam_rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key,
938 				unsigned int keylen)
939 {
940 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
941 	struct rsa_key raw_key = {NULL};
942 	struct caam_rsa_key *rsa_key = &ctx->key;
943 	int ret;
944 
945 	/* Free the old RSA key if any */
946 	caam_rsa_free_key(rsa_key);
947 
948 	ret = rsa_parse_pub_key(&raw_key, key, keylen);
949 	if (ret)
950 		return ret;
951 
952 	/* Copy key in DMA zone */
953 	rsa_key->e = kmemdup(raw_key.e, raw_key.e_sz, GFP_KERNEL);
954 	if (!rsa_key->e)
955 		goto err;
956 
957 	/*
958 	 * Skip leading zeros and copy the positive integer to a buffer
959 	 * allocated in the GFP_KERNEL zone. The decryption descriptor
960 	 * expects a positive integer for the RSA modulus and uses its length as
961 	 * decryption output length.
962 	 */
963 	rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
964 	if (!rsa_key->n)
965 		goto err;
966 
967 	if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
968 		caam_rsa_free_key(rsa_key);
969 		return -EINVAL;
970 	}
971 
972 	rsa_key->e_sz = raw_key.e_sz;
973 	rsa_key->n_sz = raw_key.n_sz;
974 
975 	return 0;
976 err:
977 	caam_rsa_free_key(rsa_key);
978 	return -ENOMEM;
979 }
980 
981 static void caam_rsa_set_priv_key_form(struct caam_rsa_ctx *ctx,
982 				       struct rsa_key *raw_key)
983 {
984 	struct caam_rsa_key *rsa_key = &ctx->key;
985 	size_t p_sz = raw_key->p_sz;
986 	size_t q_sz = raw_key->q_sz;
987 	unsigned aligned_size;
988 
989 	rsa_key->p = caam_read_raw_data(raw_key->p, &p_sz);
990 	if (!rsa_key->p)
991 		return;
992 	rsa_key->p_sz = p_sz;
993 
994 	rsa_key->q = caam_read_raw_data(raw_key->q, &q_sz);
995 	if (!rsa_key->q)
996 		goto free_p;
997 	rsa_key->q_sz = q_sz;
998 
999 	aligned_size = ALIGN(raw_key->p_sz, dma_get_cache_alignment());
1000 	rsa_key->tmp1 = kzalloc(aligned_size, GFP_KERNEL);
1001 	if (!rsa_key->tmp1)
1002 		goto free_q;
1003 
1004 	aligned_size = ALIGN(raw_key->q_sz, dma_get_cache_alignment());
1005 	rsa_key->tmp2 = kzalloc(aligned_size, GFP_KERNEL);
1006 	if (!rsa_key->tmp2)
1007 		goto free_tmp1;
1008 
1009 	rsa_key->priv_form = FORM2;
1010 
1011 	rsa_key->dp = caam_read_rsa_crt(raw_key->dp, raw_key->dp_sz, p_sz);
1012 	if (!rsa_key->dp)
1013 		goto free_tmp2;
1014 
1015 	rsa_key->dq = caam_read_rsa_crt(raw_key->dq, raw_key->dq_sz, q_sz);
1016 	if (!rsa_key->dq)
1017 		goto free_dp;
1018 
1019 	rsa_key->qinv = caam_read_rsa_crt(raw_key->qinv, raw_key->qinv_sz,
1020 					  q_sz);
1021 	if (!rsa_key->qinv)
1022 		goto free_dq;
1023 
1024 	rsa_key->priv_form = FORM3;
1025 
1026 	return;
1027 
1028 free_dq:
1029 	kfree_sensitive(rsa_key->dq);
1030 free_dp:
1031 	kfree_sensitive(rsa_key->dp);
1032 free_tmp2:
1033 	kfree_sensitive(rsa_key->tmp2);
1034 free_tmp1:
1035 	kfree_sensitive(rsa_key->tmp1);
1036 free_q:
1037 	kfree_sensitive(rsa_key->q);
1038 free_p:
1039 	kfree_sensitive(rsa_key->p);
1040 }
1041 
1042 static int caam_rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key,
1043 				 unsigned int keylen)
1044 {
1045 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
1046 	struct rsa_key raw_key = {NULL};
1047 	struct caam_rsa_key *rsa_key = &ctx->key;
1048 	int ret;
1049 
1050 	/* Free the old RSA key if any */
1051 	caam_rsa_free_key(rsa_key);
1052 
1053 	ret = rsa_parse_priv_key(&raw_key, key, keylen);
1054 	if (ret)
1055 		return ret;
1056 
1057 	/* Copy key in DMA zone */
1058 	rsa_key->d = kmemdup(raw_key.d, raw_key.d_sz, GFP_KERNEL);
1059 	if (!rsa_key->d)
1060 		goto err;
1061 
1062 	rsa_key->e = kmemdup(raw_key.e, raw_key.e_sz, GFP_KERNEL);
1063 	if (!rsa_key->e)
1064 		goto err;
1065 
1066 	/*
1067 	 * Skip leading zeros and copy the positive integer to a buffer
1068 	 * allocated in the GFP_KERNEL zone. The decryption descriptor
1069 	 * expects a positive integer for the RSA modulus and uses its length as
1070 	 * decryption output length.
1071 	 */
1072 	rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
1073 	if (!rsa_key->n)
1074 		goto err;
1075 
1076 	if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
1077 		caam_rsa_free_key(rsa_key);
1078 		return -EINVAL;
1079 	}
1080 
1081 	rsa_key->d_sz = raw_key.d_sz;
1082 	rsa_key->e_sz = raw_key.e_sz;
1083 	rsa_key->n_sz = raw_key.n_sz;
1084 
1085 	caam_rsa_set_priv_key_form(ctx, &raw_key);
1086 
1087 	return 0;
1088 
1089 err:
1090 	caam_rsa_free_key(rsa_key);
1091 	return -ENOMEM;
1092 }
1093 
1094 static unsigned int caam_rsa_max_size(struct crypto_akcipher *tfm)
1095 {
1096 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
1097 
1098 	return ctx->key.n_sz;
1099 }
1100 
1101 /* Per session pkc's driver context creation function */
1102 static int caam_rsa_init_tfm(struct crypto_akcipher *tfm)
1103 {
1104 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
1105 
1106 	akcipher_set_reqsize(tfm, sizeof(struct caam_rsa_req_ctx));
1107 
1108 	ctx->dev = caam_jr_alloc();
1109 
1110 	if (IS_ERR(ctx->dev)) {
1111 		pr_err("Job Ring Device allocation for transform failed\n");
1112 		return PTR_ERR(ctx->dev);
1113 	}
1114 
1115 	ctx->padding_dma = dma_map_single(ctx->dev, zero_buffer,
1116 					  CAAM_RSA_MAX_INPUT_SIZE - 1,
1117 					  DMA_TO_DEVICE);
1118 	if (dma_mapping_error(ctx->dev, ctx->padding_dma)) {
1119 		dev_err(ctx->dev, "unable to map padding\n");
1120 		caam_jr_free(ctx->dev);
1121 		return -ENOMEM;
1122 	}
1123 
1124 	ctx->enginectx.op.do_one_request = akcipher_do_one_req;
1125 
1126 	return 0;
1127 }
1128 
1129 /* Per session pkc's driver context cleanup function */
1130 static void caam_rsa_exit_tfm(struct crypto_akcipher *tfm)
1131 {
1132 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx_dma(tfm);
1133 	struct caam_rsa_key *key = &ctx->key;
1134 
1135 	dma_unmap_single(ctx->dev, ctx->padding_dma, CAAM_RSA_MAX_INPUT_SIZE -
1136 			 1, DMA_TO_DEVICE);
1137 	caam_rsa_free_key(key);
1138 	caam_jr_free(ctx->dev);
1139 }
1140 
1141 static struct caam_akcipher_alg caam_rsa = {
1142 	.akcipher = {
1143 		.encrypt = caam_rsa_enc,
1144 		.decrypt = caam_rsa_dec,
1145 		.set_pub_key = caam_rsa_set_pub_key,
1146 		.set_priv_key = caam_rsa_set_priv_key,
1147 		.max_size = caam_rsa_max_size,
1148 		.init = caam_rsa_init_tfm,
1149 		.exit = caam_rsa_exit_tfm,
1150 		.base = {
1151 			.cra_name = "rsa",
1152 			.cra_driver_name = "rsa-caam",
1153 			.cra_priority = 3000,
1154 			.cra_module = THIS_MODULE,
1155 			.cra_ctxsize = sizeof(struct caam_rsa_ctx) +
1156 				       CRYPTO_DMA_PADDING,
1157 		},
1158 	}
1159 };
1160 
1161 /* Public Key Cryptography module initialization handler */
1162 int caam_pkc_init(struct device *ctrldev)
1163 {
1164 	struct caam_drv_private *priv = dev_get_drvdata(ctrldev);
1165 	u32 pk_inst, pkha;
1166 	int err;
1167 	init_done = false;
1168 
1169 	/* Determine public key hardware accelerator presence. */
1170 	if (priv->era < 10) {
1171 		pk_inst = (rd_reg32(&priv->ctrl->perfmon.cha_num_ls) &
1172 			   CHA_ID_LS_PK_MASK) >> CHA_ID_LS_PK_SHIFT;
1173 	} else {
1174 		pkha = rd_reg32(&priv->ctrl->vreg.pkha);
1175 		pk_inst = pkha & CHA_VER_NUM_MASK;
1176 
1177 		/*
1178 		 * Newer CAAMs support partially disabled functionality. If this is the
1179 		 * case, the number is non-zero, but this bit is set to indicate that
1180 		 * no encryption or decryption is supported. Only signing and verifying
1181 		 * is supported.
1182 		 */
1183 		if (pkha & CHA_VER_MISC_PKHA_NO_CRYPT)
1184 			pk_inst = 0;
1185 	}
1186 
1187 	/* Do not register algorithms if PKHA is not present. */
1188 	if (!pk_inst)
1189 		return 0;
1190 
1191 	/* allocate zero buffer, used for padding input */
1192 	zero_buffer = kzalloc(CAAM_RSA_MAX_INPUT_SIZE - 1, GFP_KERNEL);
1193 	if (!zero_buffer)
1194 		return -ENOMEM;
1195 
1196 	err = crypto_register_akcipher(&caam_rsa.akcipher);
1197 
1198 	if (err) {
1199 		kfree(zero_buffer);
1200 		dev_warn(ctrldev, "%s alg registration failed\n",
1201 			 caam_rsa.akcipher.base.cra_driver_name);
1202 	} else {
1203 		init_done = true;
1204 		caam_rsa.registered = true;
1205 		dev_info(ctrldev, "caam pkc algorithms registered in /proc/crypto\n");
1206 	}
1207 
1208 	return err;
1209 }
1210 
1211 void caam_pkc_exit(void)
1212 {
1213 	if (!init_done)
1214 		return;
1215 
1216 	if (caam_rsa.registered)
1217 		crypto_unregister_akcipher(&caam_rsa.akcipher);
1218 
1219 	kfree(zero_buffer);
1220 }
1221