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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * sun4i-ss-hash.c - hardware cryptographic accelerator for Allwinner A20 SoC4 *5 * Copyright (C) 2013-2015 Corentin LABBE <clabbe.montjoie@gmail.com>6 *7 * This file add support for MD5 and SHA1.8 *9 * You could find the datasheet in Documentation/arch/arm/sunxi.rst10 */11#include "sun4i-ss.h"12#include <linux/unaligned.h>13#include <linux/scatterlist.h>14 15/* This is a totally arbitrary value */16#define SS_TIMEOUT 10017 18int sun4i_hash_crainit(struct crypto_tfm *tfm)19{20	struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm);21	struct ahash_alg *alg = __crypto_ahash_alg(tfm->__crt_alg);22	struct sun4i_ss_alg_template *algt;23	int err;24 25	memset(op, 0, sizeof(struct sun4i_tfm_ctx));26 27	algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash);28	op->ss = algt->ss;29 30	err = pm_runtime_resume_and_get(op->ss->dev);31	if (err < 0)32		return err;33 34	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),35				 sizeof(struct sun4i_req_ctx));36	return 0;37}38 39void sun4i_hash_craexit(struct crypto_tfm *tfm)40{41	struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm);42 43	pm_runtime_put(op->ss->dev);44}45 46/* sun4i_hash_init: initialize request context */47int sun4i_hash_init(struct ahash_request *areq)48{49	struct sun4i_req_ctx *op = ahash_request_ctx(areq);50	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);51	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);52	struct sun4i_ss_alg_template *algt;53 54	memset(op, 0, sizeof(struct sun4i_req_ctx));55 56	algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash);57	op->mode = algt->mode;58 59	return 0;60}61 62int sun4i_hash_export_md5(struct ahash_request *areq, void *out)63{64	struct sun4i_req_ctx *op = ahash_request_ctx(areq);65	struct md5_state *octx = out;66	int i;67 68	octx->byte_count = op->byte_count + op->len;69 70	memcpy(octx->block, op->buf, op->len);71 72	if (op->byte_count) {73		for (i = 0; i < 4; i++)74			octx->hash[i] = op->hash[i];75	} else {76		octx->hash[0] = SHA1_H0;77		octx->hash[1] = SHA1_H1;78		octx->hash[2] = SHA1_H2;79		octx->hash[3] = SHA1_H3;80	}81 82	return 0;83}84 85int sun4i_hash_import_md5(struct ahash_request *areq, const void *in)86{87	struct sun4i_req_ctx *op = ahash_request_ctx(areq);88	const struct md5_state *ictx = in;89	int i;90 91	sun4i_hash_init(areq);92 93	op->byte_count = ictx->byte_count & ~0x3F;94	op->len = ictx->byte_count & 0x3F;95 96	memcpy(op->buf, ictx->block, op->len);97 98	for (i = 0; i < 4; i++)99		op->hash[i] = ictx->hash[i];100 101	return 0;102}103 104int sun4i_hash_export_sha1(struct ahash_request *areq, void *out)105{106	struct sun4i_req_ctx *op = ahash_request_ctx(areq);107	struct sha1_state *octx = out;108	int i;109 110	octx->count = op->byte_count + op->len;111 112	memcpy(octx->buffer, op->buf, op->len);113 114	if (op->byte_count) {115		for (i = 0; i < 5; i++)116			octx->state[i] = op->hash[i];117	} else {118		octx->state[0] = SHA1_H0;119		octx->state[1] = SHA1_H1;120		octx->state[2] = SHA1_H2;121		octx->state[3] = SHA1_H3;122		octx->state[4] = SHA1_H4;123	}124 125	return 0;126}127 128int sun4i_hash_import_sha1(struct ahash_request *areq, const void *in)129{130	struct sun4i_req_ctx *op = ahash_request_ctx(areq);131	const struct sha1_state *ictx = in;132	int i;133 134	sun4i_hash_init(areq);135 136	op->byte_count = ictx->count & ~0x3F;137	op->len = ictx->count & 0x3F;138 139	memcpy(op->buf, ictx->buffer, op->len);140 141	for (i = 0; i < 5; i++)142		op->hash[i] = ictx->state[i];143 144	return 0;145}146 147#define SS_HASH_UPDATE 1148#define SS_HASH_FINAL 2149 150/*151 * sun4i_hash_update: update hash engine152 *153 * Could be used for both SHA1 and MD5154 * Write data by step of 32bits and put then in the SS.155 *156 * Since we cannot leave partial data and hash state in the engine,157 * we need to get the hash state at the end of this function.158 * We can get the hash state every 64 bytes159 *160 * So the first work is to get the number of bytes to write to SS modulo 64161 * The extra bytes will go to a temporary buffer op->buf storing op->len bytes162 *163 * So at the begin of update()164 * if op->len + areq->nbytes < 64165 * => all data will be written to wait buffer (op->buf) and end=0166 * if not, write all data from op->buf to the device and position end to167 * complete to 64bytes168 *169 * example 1:170 * update1 60o => op->len=60171 * update2 60o => need one more word to have 64 bytes172 * end=4173 * so write all data from op->buf and one word of SGs174 * write remaining data in op->buf175 * final state op->len=56176 */177static int sun4i_hash(struct ahash_request *areq)178{179	/*180	 * i is the total bytes read from SGs, to be compared to areq->nbytes181	 * i is important because we cannot rely on SG length since the sum of182	 * SG->length could be greater than areq->nbytes183	 *184	 * end is the position when we need to stop writing to the device,185	 * to be compared to i186	 *187	 * in_i: advancement in the current SG188	 */189	unsigned int i = 0, end, fill, min_fill, nwait, nbw = 0, j = 0, todo;190	unsigned int in_i = 0;191	u32 spaces, rx_cnt = SS_RX_DEFAULT, bf[32] = {0}, v, ivmode = 0;192	struct sun4i_req_ctx *op = ahash_request_ctx(areq);193	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);194	struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg);195	struct sun4i_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);196	struct sun4i_ss_ctx *ss = tfmctx->ss;197	struct sun4i_ss_alg_template *algt;198	struct scatterlist *in_sg = areq->src;199	struct sg_mapping_iter mi;200	int in_r, err = 0;201	size_t copied = 0;202	u32 wb = 0;203 204	dev_dbg(ss->dev, "%s %s bc=%llu len=%u mode=%x wl=%u h0=%0x",205		__func__, crypto_tfm_alg_name(areq->base.tfm),206		op->byte_count, areq->nbytes, op->mode,207		op->len, op->hash[0]);208 209	if (unlikely(!areq->nbytes) && !(op->flags & SS_HASH_FINAL))210		return 0;211 212	/* protect against overflow */213	if (unlikely(areq->nbytes > UINT_MAX - op->len)) {214		dev_err(ss->dev, "Cannot process too large request\n");215		return -EINVAL;216	}217 218	if (op->len + areq->nbytes < 64 && !(op->flags & SS_HASH_FINAL)) {219		/* linearize data to op->buf */220		copied = sg_pcopy_to_buffer(areq->src, sg_nents(areq->src),221					    op->buf + op->len, areq->nbytes, 0);222		op->len += copied;223		return 0;224	}225 226	spin_lock_bh(&ss->slock);227 228	/*229	 * if some data have been processed before,230	 * we need to restore the partial hash state231	 */232	if (op->byte_count) {233		ivmode = SS_IV_ARBITRARY;234		for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++)235			writel(op->hash[i], ss->base + SS_IV0 + i * 4);236	}237	/* Enable the device */238	writel(op->mode | SS_ENABLED | ivmode, ss->base + SS_CTL);239 240	if (!(op->flags & SS_HASH_UPDATE))241		goto hash_final;242 243	/* start of handling data */244	if (!(op->flags & SS_HASH_FINAL)) {245		end = ((areq->nbytes + op->len) / 64) * 64 - op->len;246 247		if (end > areq->nbytes || areq->nbytes - end > 63) {248			dev_err(ss->dev, "ERROR: Bound error %u %u\n",249				end, areq->nbytes);250			err = -EINVAL;251			goto release_ss;252		}253	} else {254		/* Since we have the flag final, we can go up to modulo 4 */255		if (areq->nbytes < 4)256			end = 0;257		else258			end = ((areq->nbytes + op->len) / 4) * 4 - op->len;259	}260 261	/* TODO if SGlen % 4 and !op->len then DMA */262	i = 1;263	while (in_sg && i == 1) {264		if (in_sg->length % 4)265			i = 0;266		in_sg = sg_next(in_sg);267	}268	if (i == 1 && !op->len && areq->nbytes)269		dev_dbg(ss->dev, "We can DMA\n");270 271	i = 0;272	sg_miter_start(&mi, areq->src, sg_nents(areq->src),273		       SG_MITER_FROM_SG | SG_MITER_ATOMIC);274	sg_miter_next(&mi);275	in_i = 0;276 277	do {278		/*279		 * we need to linearize in two case:280		 * - the buffer is already used281		 * - the SG does not have enough byte remaining ( < 4)282		 */283		if (op->len || (mi.length - in_i) < 4) {284			/*285			 * if we have entered here we have two reason to stop286			 * - the buffer is full287			 * - reach the end288			 */289			while (op->len < 64 && i < end) {290				/* how many bytes we can read from current SG */291				in_r = min(end - i, 64 - op->len);292				in_r = min_t(size_t, mi.length - in_i, in_r);293				memcpy(op->buf + op->len, mi.addr + in_i, in_r);294				op->len += in_r;295				i += in_r;296				in_i += in_r;297				if (in_i == mi.length) {298					sg_miter_next(&mi);299					in_i = 0;300				}301			}302			if (op->len > 3 && !(op->len % 4)) {303				/* write buf to the device */304				writesl(ss->base + SS_RXFIFO, op->buf,305					op->len / 4);306				op->byte_count += op->len;307				op->len = 0;308			}309		}310		if (mi.length - in_i > 3 && i < end) {311			/* how many bytes we can read from current SG */312			in_r = min_t(size_t, mi.length - in_i, areq->nbytes - i);313			in_r = min_t(size_t, ((mi.length - in_i) / 4) * 4, in_r);314			/* how many bytes we can write in the device*/315			todo = min3((u32)(end - i) / 4, rx_cnt, (u32)in_r / 4);316			writesl(ss->base + SS_RXFIFO, mi.addr + in_i, todo);317			op->byte_count += todo * 4;318			i += todo * 4;319			in_i += todo * 4;320			rx_cnt -= todo;321			if (!rx_cnt) {322				spaces = readl(ss->base + SS_FCSR);323				rx_cnt = SS_RXFIFO_SPACES(spaces);324			}325			if (in_i == mi.length) {326				sg_miter_next(&mi);327				in_i = 0;328			}329		}330	} while (i < end);331 332	/*333	 * Now we have written to the device all that we can,334	 * store the remaining bytes in op->buf335	 */336	if ((areq->nbytes - i) < 64) {337		while (i < areq->nbytes && in_i < mi.length && op->len < 64) {338			/* how many bytes we can read from current SG */339			in_r = min(areq->nbytes - i, 64 - op->len);340			in_r = min_t(size_t, mi.length - in_i, in_r);341			memcpy(op->buf + op->len, mi.addr + in_i, in_r);342			op->len += in_r;343			i += in_r;344			in_i += in_r;345			if (in_i == mi.length) {346				sg_miter_next(&mi);347				in_i = 0;348			}349		}350	}351 352	sg_miter_stop(&mi);353 354	/*355	 * End of data process356	 * Now if we have the flag final go to finalize part357	 * If not, store the partial hash358	 */359	if (op->flags & SS_HASH_FINAL)360		goto hash_final;361 362	writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL);363	i = 0;364	do {365		v = readl(ss->base + SS_CTL);366		i++;367	} while (i < SS_TIMEOUT && (v & SS_DATA_END));368	if (unlikely(i >= SS_TIMEOUT)) {369		dev_err_ratelimited(ss->dev,370				    "ERROR: hash end timeout %d>%d ctl=%x len=%u\n",371				    i, SS_TIMEOUT, v, areq->nbytes);372		err = -EIO;373		goto release_ss;374	}375 376	/*377	 * The datasheet isn't very clear about when to retrieve the digest. The378	 * bit SS_DATA_END is cleared when the engine has processed the data and379	 * when the digest is computed *but* it doesn't mean the digest is380	 * available in the digest registers. Hence the delay to be sure we can381	 * read it.382	 */383	ndelay(1);384 385	for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++)386		op->hash[i] = readl(ss->base + SS_MD0 + i * 4);387 388	goto release_ss;389 390/*391 * hash_final: finalize hashing operation392 *393 * If we have some remaining bytes, we write them.394 * Then ask the SS for finalizing the hashing operation395 *396 * I do not check RX FIFO size in this function since the size is 32397 * after each enabling and this function neither write more than 32 words.398 * If we come from the update part, we cannot have more than399 * 3 remaining bytes to write and SS is fast enough to not care about it.400 */401 402hash_final:403	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN4I_SS_DEBUG)) {404		algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash);405		algt->stat_req++;406	}407 408	/* write the remaining words of the wait buffer */409	if (op->len) {410		nwait = op->len / 4;411		if (nwait) {412			writesl(ss->base + SS_RXFIFO, op->buf, nwait);413			op->byte_count += 4 * nwait;414		}415 416		nbw = op->len - 4 * nwait;417		if (nbw) {418			wb = le32_to_cpup((__le32 *)(op->buf + nwait * 4));419			wb &= GENMASK((nbw * 8) - 1, 0);420 421			op->byte_count += nbw;422		}423	}424 425	/* write the remaining bytes of the nbw buffer */426	wb |= ((1 << 7) << (nbw * 8));427	((__le32 *)bf)[j++] = cpu_to_le32(wb);428 429	/*430	 * number of space to pad to obtain 64o minus 8(size) minus 4 (final 1)431	 * I take the operations from other MD5/SHA1 implementations432	 */433 434	/* last block size */435	fill = 64 - (op->byte_count % 64);436	min_fill = 2 * sizeof(u32) + (nbw ? 0 : sizeof(u32));437 438	/* if we can't fill all data, jump to the next 64 block */439	if (fill < min_fill)440		fill += 64;441 442	j += (fill - min_fill) / sizeof(u32);443 444	/* write the length of data */445	if (op->mode == SS_OP_SHA1) {446		__be64 *bits = (__be64 *)&bf[j];447		*bits = cpu_to_be64(op->byte_count << 3);448		j += 2;449	} else {450		__le64 *bits = (__le64 *)&bf[j];451		*bits = cpu_to_le64(op->byte_count << 3);452		j += 2;453	}454	writesl(ss->base + SS_RXFIFO, bf, j);455 456	/* Tell the SS to stop the hashing */457	writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL);458 459	/*460	 * Wait for SS to finish the hash.461	 * The timeout could happen only in case of bad overclocking462	 * or driver bug.463	 */464	i = 0;465	do {466		v = readl(ss->base + SS_CTL);467		i++;468	} while (i < SS_TIMEOUT && (v & SS_DATA_END));469	if (unlikely(i >= SS_TIMEOUT)) {470		dev_err_ratelimited(ss->dev,471				    "ERROR: hash end timeout %d>%d ctl=%x len=%u\n",472				    i, SS_TIMEOUT, v, areq->nbytes);473		err = -EIO;474		goto release_ss;475	}476 477	/*478	 * The datasheet isn't very clear about when to retrieve the digest. The479	 * bit SS_DATA_END is cleared when the engine has processed the data and480	 * when the digest is computed *but* it doesn't mean the digest is481	 * available in the digest registers. Hence the delay to be sure we can482	 * read it.483	 */484	ndelay(1);485 486	/* Get the hash from the device */487	if (op->mode == SS_OP_SHA1) {488		for (i = 0; i < 5; i++) {489			v = readl(ss->base + SS_MD0 + i * 4);490			if (ss->variant->sha1_in_be)491				put_unaligned_le32(v, areq->result + i * 4);492			else493				put_unaligned_be32(v, areq->result + i * 4);494		}495	} else {496		for (i = 0; i < 4; i++) {497			v = readl(ss->base + SS_MD0 + i * 4);498			put_unaligned_le32(v, areq->result + i * 4);499		}500	}501 502release_ss:503	writel(0, ss->base + SS_CTL);504	spin_unlock_bh(&ss->slock);505	return err;506}507 508int sun4i_hash_final(struct ahash_request *areq)509{510	struct sun4i_req_ctx *op = ahash_request_ctx(areq);511 512	op->flags = SS_HASH_FINAL;513	return sun4i_hash(areq);514}515 516int sun4i_hash_update(struct ahash_request *areq)517{518	struct sun4i_req_ctx *op = ahash_request_ctx(areq);519 520	op->flags = SS_HASH_UPDATE;521	return sun4i_hash(areq);522}523 524/* sun4i_hash_finup: finalize hashing operation after an update */525int sun4i_hash_finup(struct ahash_request *areq)526{527	struct sun4i_req_ctx *op = ahash_request_ctx(areq);528 529	op->flags = SS_HASH_UPDATE | SS_HASH_FINAL;530	return sun4i_hash(areq);531}532 533/* combo of init/update/final functions */534int sun4i_hash_digest(struct ahash_request *areq)535{536	int err;537	struct sun4i_req_ctx *op = ahash_request_ctx(areq);538 539	err = sun4i_hash_init(areq);540	if (err)541		return err;542 543	op->flags = SS_HASH_UPDATE | SS_HASH_FINAL;544	return sun4i_hash(areq);545}546