path: root/drivers/crypto/mediatek/mtk-sha.c

/*
 * Cryptographic API.
 *
 * Driver for EIP97 SHA1/SHA2(HMAC) acceleration.
 *
 * Copyright (c) 2016 Ryder Lee <ryder.lee@mediatek.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Some ideas are from atmel-sha.c and omap-sham.c drivers.
 */

#include <crypto/hmac.h>
#include <crypto/sha.h>
#include "mtk-platform.h"

#define SHA_ALIGN_MSK		(sizeof(u32) - 1)
#define SHA_QUEUE_SIZE		512
#define SHA_BUF_SIZE		((u32)PAGE_SIZE)

#define SHA_OP_UPDATE		1
#define SHA_OP_FINAL		2

#define SHA_DATA_LEN_MSK	cpu_to_le32(GENMASK(16, 0))
#define SHA_MAX_DIGEST_BUF_SIZE	32

/* SHA command token */
#define SHA_CT_SIZE		5
#define SHA_CT_CTRL_HDR		cpu_to_le32(0x02220000)
#define SHA_CMD0		cpu_to_le32(0x03020000)
#define SHA_CMD1		cpu_to_le32(0x21060000)
#define SHA_CMD2		cpu_to_le32(0xe0e63802)

/* SHA transform information */
#define SHA_TFM_HASH		cpu_to_le32(0x2 << 0)
#define SHA_TFM_SIZE(x)		cpu_to_le32((x) << 8)
#define SHA_TFM_START		cpu_to_le32(0x1 << 4)
#define SHA_TFM_CONTINUE	cpu_to_le32(0x1 << 5)
#define SHA_TFM_HASH_STORE	cpu_to_le32(0x1 << 19)
#define SHA_TFM_SHA1		cpu_to_le32(0x2 << 23)
#define SHA_TFM_SHA256		cpu_to_le32(0x3 << 23)
#define SHA_TFM_SHA224		cpu_to_le32(0x4 << 23)
#define SHA_TFM_SHA512		cpu_to_le32(0x5 << 23)
#define SHA_TFM_SHA384		cpu_to_le32(0x6 << 23)
#define SHA_TFM_DIGEST(x)	cpu_to_le32(((x) & GENMASK(3, 0)) << 24)

/* SHA flags */
#define SHA_FLAGS_BUSY		BIT(0)
#define	SHA_FLAGS_FINAL		BIT(1)
#define SHA_FLAGS_FINUP		BIT(2)
#define SHA_FLAGS_SG		BIT(3)
#define SHA_FLAGS_ALGO_MSK	GENMASK(8, 4)
#define SHA_FLAGS_SHA1		BIT(4)
#define SHA_FLAGS_SHA224	BIT(5)
#define SHA_FLAGS_SHA256	BIT(6)
#define SHA_FLAGS_SHA384	BIT(7)
#define SHA_FLAGS_SHA512	BIT(8)
#define SHA_FLAGS_HMAC		BIT(9)
#define SHA_FLAGS_PAD		BIT(10)

/**
 * mtk_sha_info - hardware information of AES
 * @cmd:	command token, hardware instruction
 * @tfm:	transform state of cipher algorithm.
 * @state:	contains keys and initial vectors.
 *
 */
struct mtk_sha_info {
	__le32 ctrl[2];
	__le32 cmd[3];
	__le32 tfm[2];
	__le32 digest[SHA_MAX_DIGEST_BUF_SIZE];
};

struct mtk_sha_reqctx {
	struct mtk_sha_info info;
	unsigned long flags;
	unsigned long op;

	u64 digcnt;
	size_t bufcnt;
	dma_addr_t dma_addr;

	__le32 ct_hdr;
	u32 ct_size;
	dma_addr_t ct_dma;
	dma_addr_t tfm_dma;

	/* Walk state */
	struct scatterlist *sg;
	u32 offset;	/* Offset in current sg */
	u32 total;	/* Total request */
	size_t ds;
	size_t bs;

	u8 *buffer;
};

struct mtk_sha_hmac_ctx {
	struct crypto_shash	*shash;
	u8 ipad[SHA512_BLOCK_SIZE] __aligned(sizeof(u32));
	u8 opad[SHA512_BLOCK_SIZE] __aligned(sizeof(u32));
};

struct mtk_sha_ctx {
	struct mtk_cryp *cryp;
	unsigned long flags;
	u8 id;
	u8 buf[SHA_BUF_SIZE] __aligned(sizeof(u32));

	struct mtk_sha_hmac_ctx	base[0];
};

struct mtk_sha_drv {
	struct list_head dev_list;
	/* Device list lock */
	spinlock_t lock;
};

static struct mtk_sha_drv mtk_sha = {
	.dev_list = LIST_HEAD_INIT(mtk_sha.dev_list),
	.lock = __SPIN_LOCK_UNLOCKED(mtk_sha.lock),
};

static int mtk_sha_handle_queue(struct mtk_cryp *cryp, u8 id,
				struct ahash_request *req);

static inline u32 mtk_sha_read(struct mtk_cryp *cryp, u32 offset)
{
	return readl_relaxed(cryp->base + offset);
}

static inline void mtk_sha_write(struct mtk_cryp *cryp,
				 u32 offset, u32 value)
{
	writel_relaxed(value, cryp->base + offset);
}

static inline void mtk_sha_ring_shift(struct mtk_ring *ring,
				      struct mtk_desc **cmd_curr,
				      struct mtk_desc **res_curr,
				      int *count)
{
	*cmd_curr = ring->cmd_next++;
	*res_curr = ring->res_next++;
	(*count)++;

	if (ring->cmd_next == ring->cmd_base + MTK_DESC_NUM) {
		ring->cmd_next = ring->cmd_base;
		ring->res_next = ring->res_base;
	}
}

static struct mtk_cryp *mtk_sha_find_dev(struct mtk_sha_ctx *tctx)
{
	struct mtk_cryp *cryp = NULL;
	struct mtk_cryp *tmp;

	spin_lock_bh(&mtk_sha.lock);
	if (!tctx->cryp) {
		list_for_each_entry(tmp, &mtk_sha.dev_list, sha_list) {
			cryp = tmp;
			break;
		}
		tctx->cryp = cryp;
	} else {
		cryp = tctx->cryp;
	}

	/*
	 * Assign record id to tfm in round-robin fashion, and this
	 * will help tfm to bind  to corresponding descriptor rings.
	 */
	tctx->id = cryp->rec;
	cryp->rec = !cryp->rec;

	spin_unlock_bh(&mtk_sha.lock);

	return cryp;
}

static int mtk_sha_append_sg(struct mtk_sha_reqctx *ctx)
{
	size_t count;

	while ((ctx->bufcnt < SHA_BUF_SIZE) && ctx->total) {
		count = min(ctx->sg->length - ctx->offset, ctx->total);
		count = min(count, SHA_BUF_SIZE - ctx->bufcnt);

		if (count <= 0) {
			/*
			 * Check if count <= 0 because the buffer is full or
			 * because the sg length is 0. In the latest case,
			 * check if there is another sg in the list, a 0 length
			 * sg doesn't necessarily mean the end of the sg list.
			 */
			if ((ctx->sg->length == 0) && !sg_is_last(ctx->sg)) {
				ctx->sg = sg_next(ctx->sg);
				continue;
			} else {
				break;
			}
		}

		scatterwalk_map_and_copy(ctx->buffer + ctx->bufcnt, ctx->sg,
					 ctx->offset, count, 0);

		ctx->bufcnt += count;
		ctx->offset += count;
		ctx->total -= count;

		if (ctx->offset == ctx->sg->length) {
			ctx->sg = sg_next(ctx->sg);
			if (ctx->sg)
				ctx->offset = 0;
			else
				ctx->total = 0;
		}
	}

	return 0;
}

/*
 * The purpose of this padding is to ensure that the padded message is a
 * multiple of 512 bits (SHA1/SHA224/SHA256) or 1024 bits (SHA384/SHA512).
 * The bit "1" is appended at the end of the message followed by
 * "padlen-1" zero bits. Then a 64 bits block (SHA1/SHA224/SHA256) or
 * 128 bits block (SHA384/SHA512) equals to the message length in bits
 * is appended.
 *
 * For SHA1/SHA224/SHA256, padlen is calculated as followed:
 *  - if message length < 56 bytes then padlen = 56 - message length
 *  - else padlen = 64 + 56 - message length
 *
 * For SHA384/SHA512, padlen is calculated as followed:
 *  - if message length < 112 bytes then padlen = 112 - message length
 *  - else padlen = 128 + 112 - message length
 */
static void mtk_sha_fill_padding(struct mtk_sha_reqctx *ctx, u32 len)
{
	u32 index, padlen;
	u64 bits[2];
	u64 size = ctx->digcnt;

	size += ctx->bufcnt;
	size += len;

	bits[1] = cpu_to_be64(size << 3);
	bits[0] = cpu_to_be64(size >> 61);

	switch (ctx->flags & SHA_FLAGS_ALGO_MSK) {
	case SHA_FLAGS_SHA384:
	case SHA_FLAGS_SHA512:
		index = ctx->bufcnt & 0x7f;
		padlen = (index < 112) ? (112 - index) : ((128 + 112) - index);
		*(ctx->buffer + ctx->bufcnt) = 0x80;
		memset(ctx->buffer + ctx->bufcnt + 1, 0, padlen - 1);
		memcpy(ctx->buffer + ctx->bufcnt + padlen, bits, 16);
		ctx->bufcnt += padlen + 16;
		ctx->flags |= SHA_FLAGS_PAD;
		break;

	default:
		index = ctx->bufcnt & 0x3f;
		padlen = (index < 56) ? (56 - index) : ((64 + 56) - index);
		*(ctx->buffer + ctx->bufcnt) = 0x80;
		memset(ctx->buffer + ctx->bufcnt + 1, 0, padlen - 1);
		memcpy(ctx->buffer + ctx->bufcnt + padlen, &bits[1], 8);
		ctx->bufcnt += padlen + 8;
		ctx->flags |= SHA_FLAGS_PAD;
		break;
	}
}

/* Initialize basic transform information of SHA */
static void mtk_sha_info_init(struct mtk_sha_reqctx *ctx)
{
	struct mtk_sha_info *info = &ctx->info;

	ctx->ct_hdr = SHA_CT_CTRL_HDR;
	ctx->ct_size = SHA_CT_SIZE;

	info->tfm[0] = SHA_TFM_HASH | SHA_TFM_SIZE(SIZE_IN_WORDS(ctx->ds));

	switch (ctx->flags & SHA_FLAGS_ALGO_MSK) {
	case SHA_FLAGS_SHA1:
		info->tfm[0] |= SHA_TFM_SHA1;
		break;
	case SHA_FLAGS_SHA224:
		info->tfm[0] |= SHA_TFM_SHA224;
		break;
	case SHA_FLAGS_SHA256:
		info->tfm[0] |= SHA_TFM_SHA256;
		break;
	case SHA_FLAGS_SHA384:
		info->tfm[0] |= SHA_TFM_SHA384;
		break;
	case SHA_FLAGS_SHA512:
		info->tfm[0] |= SHA_TFM_SHA512;
		break;

	default:
		/* Should not happen... */
		return;
	}

	info->tfm[1] = SHA_TFM_HASH_STORE;
	info->ctrl[0] = info->tfm[0] | SHA_TFM_CONTINUE | SHA_TFM_START;
	info->ctrl[1] = info->tfm[1];

	info->cmd[0] = SHA_CMD0;
	info->cmd[1] = SHA_CMD1;
	info->cmd[2] = SHA_CMD2 | SHA_TFM_DIGEST(SIZE_IN_WORDS(ctx->ds));
}

/*
 * Update input data length field of transform information and
 * map it to DMA region.
 */
static int mtk_sha_info_update(struct mtk_cryp *cryp,
			       struct mtk_sha_rec *sha,
			       size_t len1, size_t len2)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(sha->req);
	struct mtk_sha_info *info = &ctx->info;

	ctx->ct_hdr &= ~SHA_DATA_LEN_MSK;
	ctx->ct_hdr |= cpu_to_le32(len1 + len2);
	info->cmd[0] &= ~SHA_DATA_LEN_MSK;
	info->cmd[0] |= cpu_to_le32(len1 + len2);

	/* Setting SHA_TFM_START only for the first iteration */
	if (ctx->digcnt)
		info->ctrl[0] &= ~SHA_TFM_START;

	ctx->digcnt += len1;

	ctx->ct_dma = dma_map_single(cryp->dev, info, sizeof(*info),
				     DMA_BIDIRECTIONAL);
	if (unlikely(dma_mapping_error(cryp->dev, ctx->ct_dma))) {
		dev_err(cryp->dev, "dma %zu bytes error\n", sizeof(*info));
		return -EINVAL;
	}

	ctx->tfm_dma = ctx->ct_dma + sizeof(info->ctrl) + sizeof(info->cmd);

	return 0;
}

/*
 * Because of hardware limitation, we must pre-calculate the inner
 * and outer digest that need to be processed firstly by engine, then
 * apply the result digest to the input message. These complex hashing
 * procedures limits HMAC performance, so we use fallback SW encoding.
 */
static int mtk_sha_finish_hmac(struct ahash_request *req)
{
	struct mtk_sha_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
	struct mtk_sha_hmac_ctx *bctx = tctx->base;
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);

	SHASH_DESC_ON_STACK(shash, bctx->shash);

	shash->tfm = bctx->shash;
	shash->flags = 0; /* not CRYPTO_TFM_REQ_MAY_SLEEP */

	return crypto_shash_init(shash) ?:
	       crypto_shash_update(shash, bctx->opad, ctx->bs) ?:
	       crypto_shash_finup(shash, req->result, ctx->ds, req->result);
}

/* Initialize request context */
static int mtk_sha_init(struct ahash_request *req)
{
	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
	struct mtk_sha_ctx *tctx = crypto_ahash_ctx(tfm);
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);

	ctx->flags = 0;
	ctx->ds = crypto_ahash_digestsize(tfm);

	switch (ctx->ds) {
	case SHA1_DIGEST_SIZE:
		ctx->flags |= SHA_FLAGS_SHA1;
		ctx->bs = SHA1_BLOCK_SIZE;
		break;
	case SHA224_DIGEST_SIZE:
		ctx->flags |= SHA_FLAGS_SHA224;
		ctx->bs = SHA224_BLOCK_SIZE;
		break;
	case SHA256_DIGEST_SIZE:
		ctx->flags |= SHA_FLAGS_SHA256;
		ctx->bs = SHA256_BLOCK_SIZE;
		break;
	case SHA384_DIGEST_SIZE:
		ctx->flags |= SHA_FLAGS_SHA384;
		ctx->bs = SHA384_BLOCK_SIZE;
		break;
	case SHA512_DIGEST_SIZE:
		ctx->flags |= SHA_FLAGS_SHA512;
		ctx->bs = SHA512_BLOCK_SIZE;
		break;
	default:
		return -EINVAL;
	}

	ctx->bufcnt = 0;
	ctx->digcnt = 0;
	ctx->buffer = tctx->buf;

	if (tctx->flags & SHA_FLAGS_HMAC) {
		struct mtk_sha_hmac_ctx *bctx = tctx->base;

		memcpy(ctx->buffer, bctx->ipad, ctx->bs);
		ctx->bufcnt = ctx->bs;
		ctx->flags |= SHA_FLAGS_HMAC;
	}

	return 0;
}

static int mtk_sha_xmit(struct mtk_cryp *cryp, struct mtk_sha_rec *sha,
			dma_addr_t addr1, size_t len1,
			dma_addr_t addr2, size_t len2)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(sha->req);
	struct mtk_ring *ring = cryp->ring[sha->id];
	struct mtk_desc *cmd, *res;
	int err, count = 0;

	err = mtk_sha_info_update(cryp, sha, len1, len2);
	if (err)
		return err;

	/* Fill in the command/result descriptors */
	mtk_sha_ring_shift(ring, &cmd, &res, &count);

	res->hdr = MTK_DESC_FIRST | MTK_DESC_BUF_LEN(len1);
	cmd->hdr = MTK_DESC_FIRST | MTK_DESC_BUF_LEN(len1) |
		   MTK_DESC_CT_LEN(ctx->ct_size);
	cmd->buf = cpu_to_le32(addr1);
	cmd->ct = cpu_to_le32(ctx->ct_dma);
	cmd->ct_hdr = ctx->ct_hdr;
	cmd->tfm = cpu_to_le32(ctx->tfm_dma);

	if (len2) {
		mtk_sha_ring_shift(ring, &cmd, &res, &count);

		res->hdr = MTK_DESC_BUF_LEN(len2);
		cmd->hdr = MTK_DESC_BUF_LEN(len2);
		cmd->buf = cpu_to_le32(addr2);
	}

	cmd->hdr |= MTK_DESC_LAST;
	res->hdr |= MTK_DESC_LAST;

	/*
	 * Make sure that all changes to the DMA ring are done before we
	 * start engine.
	 */
	wmb();
	/* Start DMA transfer */
	mtk_sha_write(cryp, RDR_PREP_COUNT(sha->id), MTK_DESC_CNT(count));
	mtk_sha_write(cryp, CDR_PREP_COUNT(sha->id), MTK_DESC_CNT(count));

	return -EINPROGRESS;
}

static int mtk_sha_dma_map(struct mtk_cryp *cryp,
			   struct mtk_sha_rec *sha,
			   struct mtk_sha_reqctx *ctx,
			   size_t count)
{
	ctx->dma_addr = dma_map_single(cryp->dev, ctx->buffer,
				       SHA_BUF_SIZE, DMA_TO_DEVICE);
	if (unlikely(dma_mapping_error(cryp->dev, ctx->dma_addr))) {
		dev_err(cryp->dev, "dma map error\n");
		return -EINVAL;
	}

	ctx->flags &= ~SHA_FLAGS_SG;

	return mtk_sha_xmit(cryp, sha, ctx->dma_addr, count, 0, 0);
}

static int mtk_sha_update_slow(struct mtk_cryp *cryp,
			       struct mtk_sha_rec *sha)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(sha->req);
	size_t count;
	u32 final;

	mtk_sha_append_sg(ctx);

	final = (ctx->flags & SHA_FLAGS_FINUP) && !ctx->total;

	dev_dbg(cryp->dev, "slow: bufcnt: %zu\n", ctx->bufcnt);

	if (final) {
		sha->flags |= SHA_FLAGS_FINAL;
		mtk_sha_fill_padding(ctx, 0);
	}

	if (final || (ctx->bufcnt == SHA_BUF_SIZE && ctx->total)) {
		count = ctx->bufcnt;
		ctx->bufcnt = 0;

		return mtk_sha_dma_map(cryp, sha, ctx, count);
	}
	return 0;
}

static int mtk_sha_update_start(struct mtk_cryp *cryp,
				struct mtk_sha_rec *sha)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(sha->req);
	u32 len, final, tail;
	struct scatterlist *sg;

	if (!ctx->total)
		return 0;

	if (ctx->bufcnt || ctx->offset)
		return mtk_sha_update_slow(cryp, sha);

	sg = ctx->sg;

	if (!IS_ALIGNED(sg->offset, sizeof(u32)))
		return mtk_sha_update_slow(cryp, sha);

	if (!sg_is_last(sg) && !IS_ALIGNED(sg->length, ctx->bs))
		/* size is not ctx->bs aligned */
		return mtk_sha_update_slow(cryp, sha);

	len = min(ctx->total, sg->length);

	if (sg_is_last(sg)) {
		if (!(ctx->flags & SHA_FLAGS_FINUP)) {
			/* not last sg must be ctx->bs aligned */
			tail = len & (ctx->bs - 1);
			len -= tail;
		}
	}

	ctx->total -= len;
	ctx->offset = len; /* offset where to start slow */

	final = (ctx->flags & SHA_FLAGS_FINUP) && !ctx->total;

	/* Add padding */
	if (final) {
		size_t count;

		tail = len & (ctx->bs - 1);
		len -= tail;
		ctx->total += tail;
		ctx->offset = len; /* offset where to start slow */

		sg = ctx->sg;
		mtk_sha_append_sg(ctx);
		mtk_sha_fill_padding(ctx, len);

		ctx->dma_addr = dma_map_single(cryp->dev, ctx->buffer,
					       SHA_BUF_SIZE, DMA_TO_DEVICE);
		if (unlikely(dma_mapping_error(cryp->dev, ctx->dma_addr))) {
			dev_err(cryp->dev, "dma map bytes error\n");
			return -EINVAL;
		}

		sha->flags |= SHA_FLAGS_FINAL;
		count = ctx->bufcnt;
		ctx->bufcnt = 0;

		if (len == 0) {
			ctx->flags &= ~SHA_FLAGS_SG;
			return mtk_sha_xmit(cryp, sha, ctx->dma_addr,
					    count, 0, 0);

		} else {
			ctx->sg = sg;
			if (!dma_map_sg(cryp->dev, ctx->sg, 1, DMA_TO_DEVICE)) {
				dev_err(cryp->dev, "dma_map_sg error\n");
				return -EINVAL;
			}

			ctx->flags |= SHA_FLAGS_SG;
			return mtk_sha_xmit(cryp, sha, sg_dma_address(ctx->sg),
					    len, ctx->dma_addr, count);
		}
	}

	if (!dma_map_sg(cryp->dev, ctx->sg, 1, DMA_TO_DEVICE)) {
		dev_err(cryp->dev, "dma_map_sg  error\n");
		return -EINVAL;
	}

	ctx->flags |= SHA_FLAGS_SG;

	return mtk_sha_xmit(cryp, sha, sg_dma_address(ctx->sg),
			    len, 0, 0);
}

static int mtk_sha_final_req(struct mtk_cryp *cryp,
			     struct mtk_sha_rec *sha)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(sha->req);
	size_t count;

	mtk_sha_fill_padding(ctx, 0);

	sha->flags |= SHA_FLAGS_FINAL;
	count = ctx->bufcnt;
	ctx->bufcnt = 0;

	return mtk_sha_dma_map(cryp, sha, ctx, count);
}

/* Copy ready hash (+ finalize hmac) */
static int mtk_sha_finish(struct ahash_request *req)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);
	__le32 *digest = ctx->info.digest;
	u32 *result = (u32 *)req->result;
	int i;

	/* Get the hash from the digest buffer */
	for (i = 0; i < SIZE_IN_WORDS(ctx->ds); i++)
		result[i] = le32_to_cpu(digest[i]);

	if (ctx->flags & SHA_FLAGS_HMAC)
		return mtk_sha_finish_hmac(req);

	return 0;
}

static void mtk_sha_finish_req(struct mtk_cryp *cryp,
			       struct mtk_sha_rec *sha,
			       int err)
{
	if (likely(!err && (SHA_FLAGS_FINAL & sha->flags)))
		err = mtk_sha_finish(sha->req);

	sha->flags &= ~(SHA_FLAGS_BUSY | SHA_FLAGS_FINAL);

	sha->req->base.complete(&sha->req->base, err);

	/* Handle new request */
	tasklet_schedule(&sha->queue_task);
}

static int mtk_sha_handle_queue(struct mtk_cryp *cryp, u8 id,
				struct ahash_request *req)
{
	struct mtk_sha_rec *sha = cryp->sha[id];
	struct crypto_async_request *async_req, *backlog;
	struct mtk_sha_reqctx *ctx;
	unsigned long flags;
	int err = 0, ret = 0;

	spin_lock_irqsave(&sha->lock, flags);
	if (req)
		ret = ahash_enqueue_request(&sha->queue, req);

	if (SHA_FLAGS_BUSY & sha->flags) {
		spin_unlock_irqrestore(&sha->lock, flags);
		return ret;
	}

	backlog = crypto_get_backlog(&sha->queue);
	async_req = crypto_dequeue_request(&sha->queue);
	if (async_req)
		sha->flags |= SHA_FLAGS_BUSY;
	spin_unlock_irqrestore(&sha->lock, flags);

	if (!async_req)
		return ret;

	if (backlog)
		backlog->complete(backlog, -EINPROGRESS);

	req = ahash_request_cast(async_req);
	ctx = ahash_request_ctx(req);

	sha->req = req;

	mtk_sha_info_init(ctx);

	if (ctx->op == SHA_OP_UPDATE) {
		err = mtk_sha_update_start(cryp, sha);
		if (err != -EINPROGRESS && (ctx->flags & SHA_FLAGS_FINUP))
			/* No final() after finup() */
			err = mtk_sha_final_req(cryp, sha);
	} else if (ctx->op == SHA_OP_FINAL) {
		err = mtk_sha_final_req(cryp, sha);
	}

	if (unlikely(err != -EINPROGRESS))
		/* Task will not finish it, so do it here */
		mtk_sha_finish_req(cryp, sha, err);

	return ret;
}

static int mtk_sha_enqueue(struct ahash_request *req, u32 op)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);
	struct mtk_sha_ctx *tctx = crypto_tfm_ctx(req->base.tfm);

	ctx->op = op;

	return mtk_sha_handle_queue(tctx->cryp, tctx->id, req);
}

static void mtk_sha_unmap(struct mtk_cryp *cryp, struct mtk_sha_rec *sha)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(sha->req);

	dma_unmap_single(cryp->dev, ctx->ct_dma, sizeof(ctx->info),
			 DMA_BIDIRECTIONAL);

	if (ctx->flags & SHA_FLAGS_SG) {
		dma_unmap_sg(cryp->dev, ctx->sg, 1, DMA_TO_DEVICE);
		if (ctx->sg->length == ctx->offset) {
			ctx->sg = sg_next(ctx->sg);
			if (ctx->sg)
				ctx->offset = 0;
		}
		if (ctx->flags & SHA_FLAGS_PAD) {
			dma_unmap_single(cryp->dev, ctx->dma_addr,
					 SHA_BUF_SIZE, DMA_TO_DEVICE);
		}
	} else
		dma_unmap_single(cryp->dev, ctx->dma_addr,
				 SHA_BUF_SIZE, DMA_TO_DEVICE);
}

static void mtk_sha_complete(struct mtk_cryp *cryp,
			     struct mtk_sha_rec *sha)
{
	int err = 0;

	err = mtk_sha_update_start(cryp, sha);
	if (err != -EINPROGRESS)
		mtk_sha_finish_req(cryp, sha, err);
}

static int mtk_sha_update(struct ahash_request *req)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);

	ctx->total = req->nbytes;
	ctx->sg = req->src;
	ctx->offset = 0;

	if ((ctx->bufcnt + ctx->total < SHA_BUF_SIZE) &&
	    !(ctx->flags & SHA_FLAGS_FINUP))
		return mtk_sha_append_sg(ctx);

	return mtk_sha_enqueue(req, SHA_OP_UPDATE);
}

static int mtk_sha_final(struct ahash_request *req)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);

	ctx->flags |= SHA_FLAGS_FINUP;

	if (ctx->flags & SHA_FLAGS_PAD)
		return mtk_sha_finish(req);

	return mtk_sha_enqueue(req, SHA_OP_FINAL);
}

static int mtk_sha_finup(struct ahash_request *req)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);
	int err1, err2;

	ctx->flags |= SHA_FLAGS_FINUP;

	err1 = mtk_sha_update(req);
	if (err1 == -EINPROGRESS || err1 == -EBUSY)
		return err1;
	/*
	 * final() has to be always called to cleanup resources
	 * even if update() failed
	 */
	err2 = mtk_sha_final(req);

	return err1 ?: err2;
}

static int mtk_sha_digest(struct ahash_request *req)
{
	return mtk_sha_init(req) ?: mtk_sha_finup(req);
}

static int mtk_sha_setkey(struct crypto_ahash *tfm, const u8 *key,
			  u32 keylen)
{
	struct mtk_sha_ctx *tctx = crypto_ahash_ctx(tfm);
	struct mtk_sha_hmac_ctx *bctx = tctx->base;
	size_t bs = crypto_shash_blocksize(bctx->shash);
	size_t ds = crypto_shash_digestsize(bctx->shash);
	int err, i;

	SHASH_DESC_ON_STACK(shash, bctx->shash);

	shash->tfm = bctx->shash;
	shash->flags = crypto_shash_get_flags(bctx->shash) &
		       CRYPTO_TFM_REQ_MAY_SLEEP;

	if (keylen > bs) {
		err = crypto_shash_digest(shash, key, keylen, bctx->ipad);
		if (err)
			return err;
		keylen = ds;
	} else {
		memcpy(bctx->ipad, key, keylen);
	}

	memset(bctx->ipad + keylen, 0, bs - keylen);
	memcpy(bctx->opad, bctx->ipad, bs);

	for (i = 0; i < bs; i++) {
		bctx->ipad[i] ^= HMAC_IPAD_VALUE;
		bctx->opad[i] ^= HMAC_OPAD_VALUE;
	}

	return 0;
}

static int mtk_sha_export(struct ahash_request *req, void *out)
{
	const struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);

	memcpy(out, ctx, sizeof(*ctx));
	return 0;
}

static int mtk_sha_import(struct ahash_request *req, const void *in)
{
	struct mtk_sha_reqctx *ctx = ahash_request_ctx(req);

	memcpy(ctx, in, sizeof(*ctx));
	return 0;
}

static int mtk_sha_cra_init_alg(struct crypto_tfm *tfm,
				const char *alg_base)
{
	struct mtk_sha_ctx *tctx = crypto_tfm_ctx(tfm);
	struct mtk_cryp *cryp = NULL;

	cryp = mtk_sha_find_dev(tctx);
	if (!cryp)
		return -ENODEV;

	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
				 sizeof(struct mtk_sha_reqctx));

	if (alg_base) {
		struct mtk_sha_hmac_ctx *bctx = tctx->base;

		tctx->flags |= SHA_FLAGS_HMAC;
		bctx->shash = crypto_alloc_shash(alg_base, 0,
					CRYPTO_ALG_NEED_FALLBACK);
		if (IS_ERR(bctx->shash)) {
			pr_err("base driver %s could not be loaded.\n",
			       alg_base);

			return PTR_ERR(bctx->shash);
		}
	}
	return 0;
}

static int mtk_sha_cra_init(struct crypto_tfm *tfm)
{
	return mtk_sha_cra_init_alg(tfm, NULL);
}

static int mtk_sha_cra_sha1_init(struct crypto_tfm *tfm)
{
	return mtk_sha_cra_init_alg(tfm, "sha1");
}

static int mtk_sha_cra_sha224_init(struct crypto_tfm *tfm)
{
	return mtk_sha_cra_init_alg(tfm, "sha224");
}

static int mtk_sha_cra_sha256_init(struct crypto_tfm *tfm)
{
	return mtk_sha_cra_init_alg(tfm, "sha256");
}

static int mtk_sha_cra_sha384_init(struct crypto_tfm *tfm)
{
	return mtk_sha_cra_init_alg(tfm, "sha384");
}

static int mtk_sha_cra_sha512_init(struct crypto_tfm *tfm)
{
	return mtk_sha_cra_init_alg(tfm, "sha512");
}

static void mtk_sha_cra_exit(struct crypto_tfm *tfm)
{
	struct mtk_sha_ctx *tctx = crypto_tfm_ctx(tfm);

	if (tctx->flags & SHA_FLAGS_HMAC) {
		struct mtk_sha_hmac_ctx *bctx = tctx->base;

		crypto_free_shash(bctx->shash);
	}
}

static struct ahash_alg algs_sha1_sha224_sha256[] = {
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.halg.digestsize	= SHA1_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "sha1",
		.cra_driver_name	= "mtk-sha1",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC,
		.cra_blocksize		= SHA1_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.halg.digestsize	= SHA224_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "sha224",
		.cra_driver_name	= "mtk-sha224",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC,
		.cra_blocksize		= SHA224_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.halg.digestsize	= SHA256_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "sha256",
		.cra_driver_name	= "mtk-sha256",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC,
		.cra_blocksize		= SHA256_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.setkey		= mtk_sha_setkey,
	.halg.digestsize	= SHA1_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "hmac(sha1)",
		.cra_driver_name	= "mtk-hmac-sha1",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC |
					  CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA1_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx) +
					sizeof(struct mtk_sha_hmac_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_sha1_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.setkey		= mtk_sha_setkey,
	.halg.digestsize	= SHA224_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "hmac(sha224)",
		.cra_driver_name	= "mtk-hmac-sha224",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC |
					  CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA224_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx) +
					sizeof(struct mtk_sha_hmac_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_sha224_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.setkey		= mtk_sha_setkey,
	.halg.digestsize	= SHA256_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "hmac(sha256)",
		.cra_driver_name	= "mtk-hmac-sha256",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC |
					  CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA256_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx) +
					sizeof(struct mtk_sha_hmac_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_sha256_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
};

static struct ahash_alg algs_sha384_sha512[] = {
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.halg.digestsize	= SHA384_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "sha384",
		.cra_driver_name	= "mtk-sha384",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC,
		.cra_blocksize		= SHA384_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.halg.digestsize	= SHA512_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "sha512",
		.cra_driver_name	= "mtk-sha512",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC,
		.cra_blocksize		= SHA512_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.setkey		= mtk_sha_setkey,
	.halg.digestsize	= SHA384_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "hmac(sha384)",
		.cra_driver_name	= "mtk-hmac-sha384",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC |
					  CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA384_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx) +
					sizeof(struct mtk_sha_hmac_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_sha384_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
{
	.init		= mtk_sha_init,
	.update		= mtk_sha_update,
	.final		= mtk_sha_final,
	.finup		= mtk_sha_finup,
	.digest		= mtk_sha_digest,
	.export		= mtk_sha_export,
	.import		= mtk_sha_import,
	.setkey		= mtk_sha_setkey,
	.halg.digestsize	= SHA512_DIGEST_SIZE,
	.halg.statesize = sizeof(struct mtk_sha_reqctx),
	.halg.base	= {
		.cra_name		= "hmac(sha512)",
		.cra_driver_name	= "mtk-hmac-sha512",
		.cra_priority		= 400,
		.cra_flags		= CRYPTO_ALG_ASYNC |
					  CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		= SHA512_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(struct mtk_sha_ctx) +
					sizeof(struct mtk_sha_hmac_ctx),
		.cra_alignmask		= SHA_ALIGN_MSK,
		.cra_module		= THIS_MODULE,
		.cra_init		= mtk_sha_cra_sha512_init,
		.cra_exit		= mtk_sha_cra_exit,
	}
},
};

static void mtk_sha_queue_task(unsigned long data)
{
	struct mtk_sha_rec *sha = (struct mtk_sha_rec *)data;

	mtk_sha_handle_queue(sha->cryp, sha->id - MTK_RING2, NULL);
}

static void mtk_sha_done_task(unsigned long data)
{
	struct mtk_sha_rec *sha = (struct mtk_sha_rec *)data;
	struct mtk_cryp *cryp = sha->cryp;

	mtk_sha_unmap(cryp, sha);
	mtk_sha_complete(cryp, sha);
}

static irqreturn_t mtk_sha_irq(int irq, void *dev_id)
{
	struct mtk_sha_rec *sha = (struct mtk_sha_rec *)dev_id;
	struct mtk_cryp *cryp = sha->cryp;
	u32 val = mtk_sha_read(cryp, RDR_STAT(sha->id));

	mtk_sha_write(cryp, RDR_STAT(sha->id), val);

	if (likely((SHA_FLAGS_BUSY & sha->flags))) {
		mtk_sha_write(cryp, RDR_PROC_COUNT(sha->id), MTK_CNT_RST);
		mtk_sha_write(cryp, RDR_THRESH(sha->id),
			      MTK_RDR_PROC_THRESH | MTK_RDR_PROC_MODE);

		tasklet_schedule(&sha->done_task);
	} else {
		dev_warn(cryp->dev, "SHA interrupt when no active requests.\n");
	}
	return IRQ_HANDLED;
}

/*
 * The purpose of two SHA records is used to get extra performance.
 * It is similar to mtk_aes_record_init().
 */
static int mtk_sha_record_init(struct mtk_cryp *cryp)
{
	struct mtk_sha_rec **sha = cryp->sha;
	int i, err = -ENOMEM;

	for (i = 0; i < MTK_REC_NUM; i++) {
		sha[i] = kzalloc(sizeof(**sha), GFP_KERNEL);
		if (!sha[i])
			goto err_cleanup;

		sha[i]->cryp = cryp;

		spin_lock_init(&sha[i]->lock);
		crypto_init_queue(&sha[i]->queue, SHA_QUEUE_SIZE);

		tasklet_init(&sha[i]->queue_task, mtk_sha_queue_task,
			     (unsigned long)sha[i]);
		tasklet_init(&sha[i]->done_task, mtk_sha_done_task,
			     (unsigned long)sha[i]);
	}

	/* Link to ring2 and ring3 respectively */
	sha[0]->id = MTK_RING2;
	sha[1]->id = MTK_RING3;

	cryp->rec = 1;

	return 0;

err_cleanup:
	for (; i--; )
		kfree(sha[i]);
	return err;
}

static void mtk_sha_record_free(struct mtk_cryp *cryp)
{
	int i;

	for (i = 0; i < MTK_REC_NUM; i++) {
		tasklet_kill(&cryp->sha[i]->done_task);
		tasklet_kill(&cryp->sha[i]->queue_task);

		kfree(cryp->sha[i]);
	}
}

static void mtk_sha_unregister_algs(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(algs_sha1_sha224_sha256); i++)
		crypto_unregister_ahash(&algs_sha1_sha224_sha256[i]);

	for (i = 0; i < ARRAY_SIZE(algs_sha384_sha512); i++)
		crypto_unregister_ahash(&algs_sha384_sha512[i]);
}

static int mtk_sha_register_algs(void)
{
	int err, i;

	for (i = 0; i < ARRAY_SIZE(algs_sha1_sha224_sha256); i++) {
		err = crypto_register_ahash(&algs_sha1_sha224_sha256[i]);
		if (err)
			goto err_sha_224_256_algs;
	}

	for (i = 0; i < ARRAY_SIZE(algs_sha384_sha512); i++) {
		err = crypto_register_ahash(&algs_sha384_sha512[i]);
		if (err)
			goto err_sha_384_512_algs;
	}

	return 0;

err_sha_384_512_algs:
	for (; i--; )
		crypto_unregister_ahash(&algs_sha384_sha512[i]);
	i = ARRAY_SIZE(algs_sha1_sha224_sha256);
err_sha_224_256_algs:
	for (; i--; )
		crypto_unregister_ahash(&algs_sha1_sha224_sha256[i]);

	return err;
}

int mtk_hash_alg_register(struct mtk_cryp *cryp)
{
	int err;

	INIT_LIST_HEAD(&cryp->sha_list);

	/* Initialize two hash records */
	err = mtk_sha_record_init(cryp);
	if (err)
		goto err_record;

	err = devm_request_irq(cryp->dev, cryp->irq[MTK_RING2], mtk_sha_irq,
			       0, "mtk-sha", cryp->sha[0]);
	if (err) {
		dev_err(cryp->dev, "unable to request sha irq0.\n");
		goto err_res;
	}

	err = devm_request_irq(cryp->dev, cryp->irq[MTK_RING3], mtk_sha_irq,
			       0, "mtk-sha", cryp->sha[1]);
	if (err) {
		dev_err(cryp->dev, "unable to request sha irq1.\n");
		goto err_res;
	}

	/* Enable ring2 and ring3 interrupt for hash */
	mtk_sha_write(cryp, AIC_ENABLE_SET(MTK_RING2), MTK_IRQ_RDR2);
	mtk_sha_write(cryp, AIC_ENABLE_SET(MTK_RING3), MTK_IRQ_RDR3);

	spin_lock(&mtk_sha.lock);
	list_add_tail(&cryp->sha_list, &mtk_sha.dev_list);
	spin_unlock(&mtk_sha.lock);

	err = mtk_sha_register_algs();
	if (err)
		goto err_algs;

	return 0;

err_algs:
	spin_lock(&mtk_sha.lock);
	list_del(&cryp->sha_list);
	spin_unlock(&mtk_sha.lock);
err_res:
	mtk_sha_record_free(cryp);
err_record:

	dev_err(cryp->dev, "mtk-sha initialization failed.\n");
	return err;
}

void mtk_hash_alg_release(struct mtk_cryp *cryp)
{
	spin_lock(&mtk_sha.lock);
	list_del(&cryp->sha_list);
	spin_unlock(&mtk_sha.lock);

	mtk_sha_unregister_algs();
	mtk_sha_record_free(cryp);
}