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1// SPDX-License-Identifier: GPL-2.02/*3 * sun8i-ss-hash.c - hardware cryptographic offloader for4 * Allwinner A80/A83T SoC5 *6 * Copyright (C) 2015-2020 Corentin Labbe <clabbe@baylibre.com>7 *8 * This file add support for MD5 and SHA1/SHA224/SHA256.9 *10 * You could find the datasheet in Documentation/arch/arm/sunxi.rst11 */12 13#include <crypto/hmac.h>14#include <crypto/internal/hash.h>15#include <crypto/md5.h>16#include <crypto/scatterwalk.h>17#include <crypto/sha1.h>18#include <crypto/sha2.h>19#include <linux/bottom_half.h>20#include <linux/dma-mapping.h>21#include <linux/err.h>22#include <linux/kernel.h>23#include <linux/pm_runtime.h>24#include <linux/scatterlist.h>25#include <linux/slab.h>26#include <linux/string.h>27#include "sun8i-ss.h"28 29static int sun8i_ss_hashkey(struct sun8i_ss_hash_tfm_ctx *tfmctx, const u8 *key,30			    unsigned int keylen)31{32	struct crypto_shash *xtfm;33	int ret;34 35	xtfm = crypto_alloc_shash("sha1", 0, CRYPTO_ALG_NEED_FALLBACK);36	if (IS_ERR(xtfm))37		return PTR_ERR(xtfm);38 39	ret = crypto_shash_tfm_digest(xtfm, key, keylen, tfmctx->key);40	if (ret)41		dev_err(tfmctx->ss->dev, "shash digest error ret=%d\n", ret);42 43	crypto_free_shash(xtfm);44	return ret;45}46 47int sun8i_ss_hmac_setkey(struct crypto_ahash *ahash, const u8 *key,48			 unsigned int keylen)49{50	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(ahash);51	int digestsize, i;52	int bs = crypto_ahash_blocksize(ahash);53	int ret;54 55	digestsize = crypto_ahash_digestsize(ahash);56 57	if (keylen > bs) {58		ret = sun8i_ss_hashkey(tfmctx, key, keylen);59		if (ret)60			return ret;61		tfmctx->keylen = digestsize;62	} else {63		tfmctx->keylen = keylen;64		memcpy(tfmctx->key, key, keylen);65	}66 67	tfmctx->ipad = kzalloc(bs, GFP_KERNEL);68	if (!tfmctx->ipad)69		return -ENOMEM;70	tfmctx->opad = kzalloc(bs, GFP_KERNEL);71	if (!tfmctx->opad) {72		ret = -ENOMEM;73		goto err_opad;74	}75 76	memset(tfmctx->key + tfmctx->keylen, 0, bs - tfmctx->keylen);77	memcpy(tfmctx->ipad, tfmctx->key, tfmctx->keylen);78	memcpy(tfmctx->opad, tfmctx->key, tfmctx->keylen);79	for (i = 0; i < bs; i++) {80		tfmctx->ipad[i] ^= HMAC_IPAD_VALUE;81		tfmctx->opad[i] ^= HMAC_OPAD_VALUE;82	}83 84	ret = crypto_ahash_setkey(tfmctx->fallback_tfm, key, keylen);85	if (!ret)86		return 0;87 88	memzero_explicit(tfmctx->key, keylen);89	kfree_sensitive(tfmctx->opad);90err_opad:91	kfree_sensitive(tfmctx->ipad);92	return ret;93}94 95int sun8i_ss_hash_init_tfm(struct crypto_ahash *tfm)96{97	struct sun8i_ss_hash_tfm_ctx *op = crypto_ahash_ctx(tfm);98	struct ahash_alg *alg = crypto_ahash_alg(tfm);99	struct sun8i_ss_alg_template *algt;100	int err;101 102	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash.base);103	op->ss = algt->ss;104 105	/* FALLBACK */106	op->fallback_tfm = crypto_alloc_ahash(crypto_ahash_alg_name(tfm), 0,107					      CRYPTO_ALG_NEED_FALLBACK);108	if (IS_ERR(op->fallback_tfm)) {109		dev_err(algt->ss->dev, "Fallback driver could no be loaded\n");110		return PTR_ERR(op->fallback_tfm);111	}112 113	crypto_ahash_set_statesize(tfm,114				   crypto_ahash_statesize(op->fallback_tfm));115 116	crypto_ahash_set_reqsize(tfm,117				 sizeof(struct sun8i_ss_hash_reqctx) +118				 crypto_ahash_reqsize(op->fallback_tfm));119 120	memcpy(algt->fbname, crypto_ahash_driver_name(op->fallback_tfm),121	       CRYPTO_MAX_ALG_NAME);122 123	err = pm_runtime_get_sync(op->ss->dev);124	if (err < 0)125		goto error_pm;126	return 0;127error_pm:128	pm_runtime_put_noidle(op->ss->dev);129	crypto_free_ahash(op->fallback_tfm);130	return err;131}132 133void sun8i_ss_hash_exit_tfm(struct crypto_ahash *tfm)134{135	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);136 137	kfree_sensitive(tfmctx->ipad);138	kfree_sensitive(tfmctx->opad);139 140	crypto_free_ahash(tfmctx->fallback_tfm);141	pm_runtime_put_sync_suspend(tfmctx->ss->dev);142}143 144int sun8i_ss_hash_init(struct ahash_request *areq)145{146	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);147	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);148	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);149 150	memset(rctx, 0, sizeof(struct sun8i_ss_hash_reqctx));151 152	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);153	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;154 155	return crypto_ahash_init(&rctx->fallback_req);156}157 158int sun8i_ss_hash_export(struct ahash_request *areq, void *out)159{160	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);161	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);162	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);163 164	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);165	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;166 167	return crypto_ahash_export(&rctx->fallback_req, out);168}169 170int sun8i_ss_hash_import(struct ahash_request *areq, const void *in)171{172	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);173	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);174	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);175 176	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);177	rctx->fallback_req.base.flags = areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP;178 179	return crypto_ahash_import(&rctx->fallback_req, in);180}181 182int sun8i_ss_hash_final(struct ahash_request *areq)183{184	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);185	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);186	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);187 188	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);189	rctx->fallback_req.base.flags = areq->base.flags &190					CRYPTO_TFM_REQ_MAY_SLEEP;191	rctx->fallback_req.result = areq->result;192 193	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG)) {194		struct ahash_alg *alg = crypto_ahash_alg(tfm);195		struct sun8i_ss_alg_template *algt __maybe_unused;196 197		algt = container_of(alg, struct sun8i_ss_alg_template,198				    alg.hash.base);199 200#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG201		algt->stat_fb++;202#endif203	}204 205	return crypto_ahash_final(&rctx->fallback_req);206}207 208int sun8i_ss_hash_update(struct ahash_request *areq)209{210	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);211	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);212	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);213 214	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);215	rctx->fallback_req.base.flags = areq->base.flags &216					CRYPTO_TFM_REQ_MAY_SLEEP;217	rctx->fallback_req.nbytes = areq->nbytes;218	rctx->fallback_req.src = areq->src;219 220	return crypto_ahash_update(&rctx->fallback_req);221}222 223int sun8i_ss_hash_finup(struct ahash_request *areq)224{225	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);226	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);227	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);228 229	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);230	rctx->fallback_req.base.flags = areq->base.flags &231					CRYPTO_TFM_REQ_MAY_SLEEP;232 233	rctx->fallback_req.nbytes = areq->nbytes;234	rctx->fallback_req.src = areq->src;235	rctx->fallback_req.result = areq->result;236 237	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG)) {238		struct ahash_alg *alg = crypto_ahash_alg(tfm);239		struct sun8i_ss_alg_template *algt __maybe_unused;240 241		algt = container_of(alg, struct sun8i_ss_alg_template,242				    alg.hash.base);243 244#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG245		algt->stat_fb++;246#endif247	}248 249	return crypto_ahash_finup(&rctx->fallback_req);250}251 252static int sun8i_ss_hash_digest_fb(struct ahash_request *areq)253{254	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);255	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);256	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);257 258	ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);259	rctx->fallback_req.base.flags = areq->base.flags &260					CRYPTO_TFM_REQ_MAY_SLEEP;261 262	rctx->fallback_req.nbytes = areq->nbytes;263	rctx->fallback_req.src = areq->src;264	rctx->fallback_req.result = areq->result;265 266	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG)) {267		struct ahash_alg *alg = crypto_ahash_alg(tfm);268		struct sun8i_ss_alg_template *algt __maybe_unused;269 270		algt = container_of(alg, struct sun8i_ss_alg_template,271				    alg.hash.base);272 273#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG274		algt->stat_fb++;275#endif276	}277 278	return crypto_ahash_digest(&rctx->fallback_req);279}280 281static int sun8i_ss_run_hash_task(struct sun8i_ss_dev *ss,282				  struct sun8i_ss_hash_reqctx *rctx,283				  const char *name)284{285	int flow = rctx->flow;286	u32 v = SS_START;287	int i;288 289#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG290	ss->flows[flow].stat_req++;291#endif292 293	/* choose between stream0/stream1 */294	if (flow)295		v |= SS_FLOW1;296	else297		v |= SS_FLOW0;298 299	v |= rctx->method;300 301	for (i = 0; i < MAX_SG; i++) {302		if (!rctx->t_dst[i].addr)303			break;304 305		mutex_lock(&ss->mlock);306		if (i > 0) {307			v |= BIT(17);308			writel(rctx->t_dst[i - 1].addr, ss->base + SS_KEY_ADR_REG);309			writel(rctx->t_dst[i - 1].addr, ss->base + SS_IV_ADR_REG);310		}311 312		dev_dbg(ss->dev,313			"Processing SG %d on flow %d %s ctl=%x %d to %d method=%x src=%x dst=%x\n",314			i, flow, name, v,315			rctx->t_src[i].len, rctx->t_dst[i].len,316			rctx->method, rctx->t_src[i].addr, rctx->t_dst[i].addr);317 318		writel(rctx->t_src[i].addr, ss->base + SS_SRC_ADR_REG);319		writel(rctx->t_dst[i].addr, ss->base + SS_DST_ADR_REG);320		writel(rctx->t_src[i].len, ss->base + SS_LEN_ADR_REG);321		writel(BIT(0) | BIT(1), ss->base + SS_INT_CTL_REG);322 323		reinit_completion(&ss->flows[flow].complete);324		ss->flows[flow].status = 0;325		wmb();326 327		writel(v, ss->base + SS_CTL_REG);328		mutex_unlock(&ss->mlock);329		wait_for_completion_interruptible_timeout(&ss->flows[flow].complete,330							  msecs_to_jiffies(2000));331		if (ss->flows[flow].status == 0) {332			dev_err(ss->dev, "DMA timeout for %s\n", name);333			return -EFAULT;334		}335	}336 337	return 0;338}339 340static bool sun8i_ss_hash_need_fallback(struct ahash_request *areq)341{342	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);343	struct ahash_alg *alg = crypto_ahash_alg(tfm);344	struct sun8i_ss_alg_template *algt;345	struct scatterlist *sg;346 347	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash.base);348 349	if (areq->nbytes == 0) {350		algt->stat_fb_len++;351		return true;352	}353 354	if (areq->nbytes >= MAX_PAD_SIZE - 64) {355		algt->stat_fb_len++;356		return true;357	}358 359	/* we need to reserve one SG for the padding one */360	if (sg_nents(areq->src) > MAX_SG - 1) {361		algt->stat_fb_sgnum++;362		return true;363	}364 365	sg = areq->src;366	while (sg) {367		/* SS can operate hash only on full block size368		 * since SS support only MD5,sha1,sha224 and sha256, blocksize369		 * is always 64370		 */371		/* Only the last block could be bounced to the pad buffer */372		if (sg->length % 64 && sg_next(sg)) {373			algt->stat_fb_sglen++;374			return true;375		}376		if (!IS_ALIGNED(sg->offset, sizeof(u32))) {377			algt->stat_fb_align++;378			return true;379		}380		if (sg->length % 4) {381			algt->stat_fb_sglen++;382			return true;383		}384		sg = sg_next(sg);385	}386	return false;387}388 389int sun8i_ss_hash_digest(struct ahash_request *areq)390{391	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);392	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);393	struct ahash_alg *alg = crypto_ahash_alg(tfm);394	struct sun8i_ss_alg_template *algt;395	struct sun8i_ss_dev *ss;396	struct crypto_engine *engine;397	int e;398 399	if (sun8i_ss_hash_need_fallback(areq))400		return sun8i_ss_hash_digest_fb(areq);401 402	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash.base);403	ss = algt->ss;404 405	e = sun8i_ss_get_engine_number(ss);406	rctx->flow = e;407	engine = ss->flows[e].engine;408 409	return crypto_transfer_hash_request_to_engine(engine, areq);410}411 412static u64 hash_pad(__le32 *buf, unsigned int bufsize, u64 padi, u64 byte_count, bool le, int bs)413{414	u64 fill, min_fill, j, k;415	__be64 *bebits;416	__le64 *lebits;417 418	j = padi;419	buf[j++] = cpu_to_le32(0x80);420 421	if (bs == 64) {422		fill = 64 - (byte_count % 64);423		min_fill = 2 * sizeof(u32) + sizeof(u32);424	} else {425		fill = 128 - (byte_count % 128);426		min_fill = 4 * sizeof(u32) + sizeof(u32);427	}428 429	if (fill < min_fill)430		fill += bs;431 432	k = j;433	j += (fill - min_fill) / sizeof(u32);434	if (j * 4 > bufsize) {435		pr_err("%s OVERFLOW %llu\n", __func__, j);436		return 0;437	}438	for (; k < j; k++)439		buf[k] = 0;440 441	if (le) {442		/* MD5 */443		lebits = (__le64 *)&buf[j];444		*lebits = cpu_to_le64(byte_count << 3);445		j += 2;446	} else {447		if (bs == 64) {448			/* sha1 sha224 sha256 */449			bebits = (__be64 *)&buf[j];450			*bebits = cpu_to_be64(byte_count << 3);451			j += 2;452		} else {453			/* sha384 sha512*/454			bebits = (__be64 *)&buf[j];455			*bebits = cpu_to_be64(byte_count >> 61);456			j += 2;457			bebits = (__be64 *)&buf[j];458			*bebits = cpu_to_be64(byte_count << 3);459			j += 2;460		}461	}462	if (j * 4 > bufsize) {463		pr_err("%s OVERFLOW %llu\n", __func__, j);464		return 0;465	}466 467	return j;468}469 470/* sun8i_ss_hash_run - run an ahash request471 * Send the data of the request to the SS along with an extra SG with padding472 */473int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq)474{475	struct ahash_request *areq = container_of(breq, struct ahash_request, base);476	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);477	struct sun8i_ss_hash_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);478	struct sun8i_ss_hash_reqctx *rctx = ahash_request_ctx(areq);479	struct ahash_alg *alg = crypto_ahash_alg(tfm);480	struct sun8i_ss_alg_template *algt;481	struct sun8i_ss_dev *ss;482	struct scatterlist *sg;483	int bs = crypto_ahash_blocksize(tfm);484	int nr_sgs, err, digestsize;485	unsigned int len;486	u64 byte_count;487	void *pad, *result;488	int j, i, k, todo;489	dma_addr_t addr_res, addr_pad, addr_xpad;490	__le32 *bf;491	/* HMAC step:492	 * 0: normal hashing493	 * 1: IPAD494	 * 2: OPAD495	 */496	int hmac = 0;497 498	algt = container_of(alg, struct sun8i_ss_alg_template, alg.hash.base);499	ss = algt->ss;500 501	digestsize = crypto_ahash_digestsize(tfm);502	if (digestsize == SHA224_DIGEST_SIZE)503		digestsize = SHA256_DIGEST_SIZE;504 505	result = ss->flows[rctx->flow].result;506	pad = ss->flows[rctx->flow].pad;507	bf = (__le32 *)pad;508 509	for (i = 0; i < MAX_SG; i++) {510		rctx->t_dst[i].addr = 0;511		rctx->t_dst[i].len = 0;512	}513 514#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG515	algt->stat_req++;516#endif517 518	rctx->method = ss->variant->alg_hash[algt->ss_algo_id];519 520	nr_sgs = dma_map_sg(ss->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);521	if (nr_sgs <= 0 || nr_sgs > MAX_SG) {522		dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);523		err = -EINVAL;524		goto theend;525	}526 527	addr_res = dma_map_single(ss->dev, result, digestsize, DMA_FROM_DEVICE);528	if (dma_mapping_error(ss->dev, addr_res)) {529		dev_err(ss->dev, "DMA map dest\n");530		err = -EINVAL;531		goto err_dma_result;532	}533 534	j = 0;535	len = areq->nbytes;536	sg = areq->src;537	i = 0;538	while (len > 0 && sg) {539		if (sg_dma_len(sg) == 0) {540			sg = sg_next(sg);541			continue;542		}543		todo = min(len, sg_dma_len(sg));544		/* only the last SG could be with a size not modulo64 */545		if (todo % 64 == 0) {546			rctx->t_src[i].addr = sg_dma_address(sg);547			rctx->t_src[i].len = todo / 4;548			rctx->t_dst[i].addr = addr_res;549			rctx->t_dst[i].len = digestsize / 4;550			len -= todo;551		} else {552			scatterwalk_map_and_copy(bf, sg, 0, todo, 0);553			j += todo / 4;554			len -= todo;555		}556		sg = sg_next(sg);557		i++;558	}559	if (len > 0) {560		dev_err(ss->dev, "remaining len %d\n", len);561		err = -EINVAL;562		goto theend;563	}564 565	if (j > 0)566		i--;567 568retry:569	byte_count = areq->nbytes;570	if (tfmctx->keylen && hmac == 0) {571		hmac = 1;572		/* shift all SG one slot up, to free slot 0 for IPAD */573		for (k = 6; k >= 0; k--) {574			rctx->t_src[k + 1].addr = rctx->t_src[k].addr;575			rctx->t_src[k + 1].len = rctx->t_src[k].len;576			rctx->t_dst[k + 1].addr = rctx->t_dst[k].addr;577			rctx->t_dst[k + 1].len = rctx->t_dst[k].len;578		}579		addr_xpad = dma_map_single(ss->dev, tfmctx->ipad, bs, DMA_TO_DEVICE);580		err = dma_mapping_error(ss->dev, addr_xpad);581		if (err) {582			dev_err(ss->dev, "Fail to create DMA mapping of ipad\n");583			goto err_dma_xpad;584		}585		rctx->t_src[0].addr = addr_xpad;586		rctx->t_src[0].len = bs / 4;587		rctx->t_dst[0].addr = addr_res;588		rctx->t_dst[0].len = digestsize / 4;589		i++;590		byte_count = areq->nbytes + bs;591	}592	if (tfmctx->keylen && hmac == 2) {593		for (i = 0; i < MAX_SG; i++) {594			rctx->t_src[i].addr = 0;595			rctx->t_src[i].len = 0;596			rctx->t_dst[i].addr = 0;597			rctx->t_dst[i].len = 0;598		}599 600		addr_res = dma_map_single(ss->dev, result, digestsize, DMA_FROM_DEVICE);601		if (dma_mapping_error(ss->dev, addr_res)) {602			dev_err(ss->dev, "Fail to create DMA mapping of result\n");603			err = -EINVAL;604			goto err_dma_result;605		}606		addr_xpad = dma_map_single(ss->dev, tfmctx->opad, bs, DMA_TO_DEVICE);607		err = dma_mapping_error(ss->dev, addr_xpad);608		if (err) {609			dev_err(ss->dev, "Fail to create DMA mapping of opad\n");610			goto err_dma_xpad;611		}612		rctx->t_src[0].addr = addr_xpad;613		rctx->t_src[0].len = bs / 4;614 615		memcpy(bf, result, digestsize);616		j = digestsize / 4;617		i = 1;618		byte_count = digestsize + bs;619 620		rctx->t_dst[0].addr = addr_res;621		rctx->t_dst[0].len = digestsize / 4;622	}623 624	switch (algt->ss_algo_id) {625	case SS_ID_HASH_MD5:626		j = hash_pad(bf, 4096, j, byte_count, true, bs);627		break;628	case SS_ID_HASH_SHA1:629	case SS_ID_HASH_SHA224:630	case SS_ID_HASH_SHA256:631		j = hash_pad(bf, 4096, j, byte_count, false, bs);632		break;633	}634	if (!j) {635		err = -EINVAL;636		goto theend;637	}638 639	addr_pad = dma_map_single(ss->dev, pad, j * 4, DMA_TO_DEVICE);640	if (dma_mapping_error(ss->dev, addr_pad)) {641		dev_err(ss->dev, "DMA error on padding SG\n");642		err = -EINVAL;643		goto err_dma_pad;644	}645	rctx->t_src[i].addr = addr_pad;646	rctx->t_src[i].len = j;647	rctx->t_dst[i].addr = addr_res;648	rctx->t_dst[i].len = digestsize / 4;649 650	err = sun8i_ss_run_hash_task(ss, rctx, crypto_tfm_alg_name(areq->base.tfm));651 652	/*653	 * mini helper for checking dma map/unmap654	 * flow start for hmac = 0 (and HMAC = 1)655	 * HMAC = 0656	 * MAP src657	 * MAP res658	 *659	 * retry:660	 * if hmac then hmac = 1661	 *	MAP xpad (ipad)662	 * if hmac == 2663	 *	MAP res664	 *	MAP xpad (opad)665	 * MAP pad666	 * ACTION!667	 * UNMAP pad668	 * if hmac669	 *	UNMAP xpad670	 * UNMAP res671	 * if hmac < 2672	 *	UNMAP SRC673	 *674	 * if hmac = 1 then hmac = 2 goto retry675	 */676 677	dma_unmap_single(ss->dev, addr_pad, j * 4, DMA_TO_DEVICE);678 679err_dma_pad:680	if (hmac > 0)681		dma_unmap_single(ss->dev, addr_xpad, bs, DMA_TO_DEVICE);682err_dma_xpad:683	dma_unmap_single(ss->dev, addr_res, digestsize, DMA_FROM_DEVICE);684err_dma_result:685	if (hmac < 2)686		dma_unmap_sg(ss->dev, areq->src, sg_nents(areq->src),687			     DMA_TO_DEVICE);688	if (hmac == 1 && !err) {689		hmac = 2;690		goto retry;691	}692 693	if (!err)694		memcpy(areq->result, result, crypto_ahash_digestsize(tfm));695theend:696	local_bh_disable();697	crypto_finalize_hash_request(engine, breq, err);698	local_bh_enable();699	return 0;700}701