drivers/crypto/xilinx/zynqmp-aes-gcm.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Xilinx ZynqMP AES Driver.
  * Copyright (c) 2020 Xilinx Inc.
  */

 #include <crypto/aes.h>
 #include <crypto/engine.h>
 #include <crypto/gcm.h>
 #include <crypto/internal/aead.h>
 #include <crypto/scatterwalk.h>
 #include <linux/dma-mapping.h>
 #include <linux/err.h>
 #include <linux/firmware/xlnx-zynqmp.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
 #include <linux/platform_device.h>
 #include <linux/string.h>

 #define ZYNQMP_DMA_BIT_MASK	32U

 #define ZYNQMP_AES_KEY_SIZE		AES_KEYSIZE_256
 #define ZYNQMP_AES_AUTH_SIZE		16U
 #define ZYNQMP_KEY_SRC_SEL_KEY_LEN	1U
 #define ZYNQMP_AES_BLK_SIZE		1U
 #define ZYNQMP_AES_MIN_INPUT_BLK_SIZE	4U
 #define ZYNQMP_AES_WORD_LEN		4U

 #define ZYNQMP_AES_GCM_TAG_MISMATCH_ERR		0x01
 #define ZYNQMP_AES_WRONG_KEY_SRC_ERR		0x13
 #define ZYNQMP_AES_PUF_NOT_PROGRAMMED		0xE300

 enum zynqmp_aead_op {
 	ZYNQMP_AES_DECRYPT = 0,
 	ZYNQMP_AES_ENCRYPT
 };

 enum zynqmp_aead_keysrc {
 	ZYNQMP_AES_KUP_KEY = 0,
 	ZYNQMP_AES_DEV_KEY,
 	ZYNQMP_AES_PUF_KEY
 };

 struct zynqmp_aead_drv_ctx {
 	union {
 		struct aead_engine_alg aead;
 	} alg;
 	struct device *dev;
 	struct crypto_engine *engine;
 };

 struct zynqmp_aead_hw_req {
 	u64 src;
 	u64 iv;
 	u64 key;
 	u64 dst;
 	u64 size;
 	u64 op;
 	u64 keysrc;
 };

 struct zynqmp_aead_tfm_ctx {
 	struct device *dev;
 	u8 key[ZYNQMP_AES_KEY_SIZE];
 	u8 *iv;
 	u32 keylen;
 	u32 authsize;
 	enum zynqmp_aead_keysrc keysrc;
 	struct crypto_aead *fbk_cipher;
 };

 struct zynqmp_aead_req_ctx {
 	enum zynqmp_aead_op op;
 };

 static int zynqmp_aes_aead_cipher(struct aead_request *req)
 {
 	struct crypto_aead *aead = crypto_aead_reqtfm(req);
 	struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead);
 	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
 	struct device *dev = tfm_ctx->dev;
 	struct zynqmp_aead_hw_req *hwreq;
 	dma_addr_t dma_addr_data, dma_addr_hw_req;
 	unsigned int data_size;
 	unsigned int status;
 	int ret;
 	size_t dma_size;
 	char *kbuf;
 	int err;

 	if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY)
 		dma_size = req->cryptlen + ZYNQMP_AES_KEY_SIZE
 			   + GCM_AES_IV_SIZE;
 	else
 		dma_size = req->cryptlen + GCM_AES_IV_SIZE;

 	kbuf = dma_alloc_coherent(dev, dma_size, &dma_addr_data, GFP_KERNEL);
 	if (!kbuf)
 		return -ENOMEM;

 	hwreq = dma_alloc_coherent(dev, sizeof(struct zynqmp_aead_hw_req),
 				   &dma_addr_hw_req, GFP_KERNEL);
 	if (!hwreq) {
 		dma_free_coherent(dev, dma_size, kbuf, dma_addr_data);
 		return -ENOMEM;
 	}

 	data_size = req->cryptlen;
 	scatterwalk_map_and_copy(kbuf, req->src, 0, req->cryptlen, 0);
 	memcpy(kbuf + data_size, req->iv, GCM_AES_IV_SIZE);

 	hwreq->src = dma_addr_data;
 	hwreq->dst = dma_addr_data;
 	hwreq->iv = hwreq->src + data_size;
 	hwreq->keysrc = tfm_ctx->keysrc;
 	hwreq->op = rq_ctx->op;

 	if (hwreq->op == ZYNQMP_AES_ENCRYPT)
 		hwreq->size = data_size;
 	else
 		hwreq->size = data_size - ZYNQMP_AES_AUTH_SIZE;

 	if (hwreq->keysrc == ZYNQMP_AES_KUP_KEY) {
 		memcpy(kbuf + data_size + GCM_AES_IV_SIZE,
 		       tfm_ctx->key, ZYNQMP_AES_KEY_SIZE);

 		hwreq->key = hwreq->src + data_size + GCM_AES_IV_SIZE;
 	} else {
 		hwreq->key = 0;
 	}

 	ret = zynqmp_pm_aes_engine(dma_addr_hw_req, &status);

 	if (ret) {
 		dev_err(dev, "ERROR: AES PM API failed\n");
 		err = ret;
 	} else if (status) {
 		switch (status) {
 		case ZYNQMP_AES_GCM_TAG_MISMATCH_ERR:
 			dev_err(dev, "ERROR: Gcm Tag mismatch\n");
 			break;
 		case ZYNQMP_AES_WRONG_KEY_SRC_ERR:
 			dev_err(dev, "ERROR: Wrong KeySrc, enable secure mode\n");
 			break;
 		case ZYNQMP_AES_PUF_NOT_PROGRAMMED:
 			dev_err(dev, "ERROR: PUF is not registered\n");
 			break;
 		default:
 			dev_err(dev, "ERROR: Unknown error\n");
 			break;
 		}
 		err = -status;
 	} else {
 		if (hwreq->op == ZYNQMP_AES_ENCRYPT)
 			data_size = data_size + ZYNQMP_AES_AUTH_SIZE;
 		else
 			data_size = data_size - ZYNQMP_AES_AUTH_SIZE;

 		sg_copy_from_buffer(req->dst, sg_nents(req->dst),
 				    kbuf, data_size);
 		err = 0;
 	}

 	if (kbuf) {
 		memzero_explicit(kbuf, dma_size);
 		dma_free_coherent(dev, dma_size, kbuf, dma_addr_data);
 	}
 	if (hwreq) {
 		memzero_explicit(hwreq, sizeof(struct zynqmp_aead_hw_req));
 		dma_free_coherent(dev, sizeof(struct zynqmp_aead_hw_req),
 				  hwreq, dma_addr_hw_req);
 	}
 	return err;
 }

 static int zynqmp_fallback_check(struct zynqmp_aead_tfm_ctx *tfm_ctx,
 				 struct aead_request *req)
 {
 	int need_fallback = 0;
 	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);

 	if (tfm_ctx->authsize != ZYNQMP_AES_AUTH_SIZE)
 		need_fallback = 1;

 	if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY &&
 	    tfm_ctx->keylen != ZYNQMP_AES_KEY_SIZE) {
 		need_fallback = 1;
 	}
 	if (req->assoclen != 0 ||
 	    req->cryptlen < ZYNQMP_AES_MIN_INPUT_BLK_SIZE) {
 		need_fallback = 1;
 	}
 	if ((req->cryptlen % ZYNQMP_AES_WORD_LEN) != 0)
 		need_fallback = 1;

 	if (rq_ctx->op == ZYNQMP_AES_DECRYPT &&
 	    req->cryptlen <= ZYNQMP_AES_AUTH_SIZE) {
 		need_fallback = 1;
 	}
 	return need_fallback;
 }

 static int zynqmp_handle_aes_req(struct crypto_engine *engine,
 				 void *req)
 {
 	struct aead_request *areq =
 				container_of(req, struct aead_request, base);
 	struct crypto_aead *aead = crypto_aead_reqtfm(req);
 	struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead);
 	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(areq);
 	struct aead_request *subreq = aead_request_ctx(req);
 	int need_fallback;
 	int err;

 	need_fallback = zynqmp_fallback_check(tfm_ctx, areq);

 	if (need_fallback) {
 		aead_request_set_tfm(subreq, tfm_ctx->fbk_cipher);

 		aead_request_set_callback(subreq, areq->base.flags,
 					  NULL, NULL);
 		aead_request_set_crypt(subreq, areq->src, areq->dst,
 				       areq->cryptlen, areq->iv);
 		aead_request_set_ad(subreq, areq->assoclen);
 		if (rq_ctx->op == ZYNQMP_AES_ENCRYPT)
 			err = crypto_aead_encrypt(subreq);
 		else
 			err = crypto_aead_decrypt(subreq);
 	} else {
 		err = zynqmp_aes_aead_cipher(areq);
 	}

 	local_bh_disable();
 	crypto_finalize_aead_request(engine, areq, err);
 	local_bh_enable();

 	return 0;
 }

 static int zynqmp_aes_aead_setkey(struct crypto_aead *aead, const u8 *key,
 				  unsigned int keylen)
 {
 	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
 	struct zynqmp_aead_tfm_ctx *tfm_ctx =
 			(struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
 	unsigned char keysrc;

 	if (keylen == ZYNQMP_KEY_SRC_SEL_KEY_LEN) {
 		keysrc = *key;
 		if (keysrc == ZYNQMP_AES_KUP_KEY ||
 		    keysrc == ZYNQMP_AES_DEV_KEY ||
 		    keysrc == ZYNQMP_AES_PUF_KEY) {
 			tfm_ctx->keysrc = (enum zynqmp_aead_keysrc)keysrc;
 		} else {
 			tfm_ctx->keylen = keylen;
 		}
 	} else {
 		tfm_ctx->keylen = keylen;
 		if (keylen == ZYNQMP_AES_KEY_SIZE) {
 			tfm_ctx->keysrc = ZYNQMP_AES_KUP_KEY;
 			memcpy(tfm_ctx->key, key, keylen);
 		}
 	}

 	tfm_ctx->fbk_cipher->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
 	tfm_ctx->fbk_cipher->base.crt_flags |= (aead->base.crt_flags &
 					CRYPTO_TFM_REQ_MASK);

 	return crypto_aead_setkey(tfm_ctx->fbk_cipher, key, keylen);
 }

 static int zynqmp_aes_aead_setauthsize(struct crypto_aead *aead,
 				       unsigned int authsize)
 {
 	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
 	struct zynqmp_aead_tfm_ctx *tfm_ctx =
 			(struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);

 	tfm_ctx->authsize = authsize;
 	return crypto_aead_setauthsize(tfm_ctx->fbk_cipher, authsize);
 }

 static int zynqmp_aes_aead_encrypt(struct aead_request *req)
 {
 	struct zynqmp_aead_drv_ctx *drv_ctx;
 	struct crypto_aead *aead = crypto_aead_reqtfm(req);
 	struct aead_alg *alg = crypto_aead_alg(aead);
 	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);

 	rq_ctx->op = ZYNQMP_AES_ENCRYPT;
 	drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead.base);

 	return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req);
 }

 static int zynqmp_aes_aead_decrypt(struct aead_request *req)
 {
 	struct zynqmp_aead_drv_ctx *drv_ctx;
 	struct crypto_aead *aead = crypto_aead_reqtfm(req);
 	struct aead_alg *alg = crypto_aead_alg(aead);
 	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);

 	rq_ctx->op = ZYNQMP_AES_DECRYPT;
 	drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead.base);

 	return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req);
 }

 static int zynqmp_aes_aead_init(struct crypto_aead *aead)
 {
 	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
 	struct zynqmp_aead_tfm_ctx *tfm_ctx =
 		(struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
 	struct zynqmp_aead_drv_ctx *drv_ctx;
 	struct aead_alg *alg = crypto_aead_alg(aead);

 	drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead.base);
 	tfm_ctx->dev = drv_ctx->dev;

 	tfm_ctx->fbk_cipher = crypto_alloc_aead(drv_ctx->alg.aead.base.base.cra_name,
 						0,
 						CRYPTO_ALG_NEED_FALLBACK);

 	if (IS_ERR(tfm_ctx->fbk_cipher)) {
 		pr_err("%s() Error: failed to allocate fallback for %s\n",
 		       __func__, drv_ctx->alg.aead.base.base.cra_name);
 		return PTR_ERR(tfm_ctx->fbk_cipher);
 	}

 	crypto_aead_set_reqsize(aead,
 				max(sizeof(struct zynqmp_aead_req_ctx),
 				    sizeof(struct aead_request) +
 				    crypto_aead_reqsize(tfm_ctx->fbk_cipher)));
 	return 0;
 }

 static void zynqmp_aes_aead_exit(struct crypto_aead *aead)
 {
 	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
 	struct zynqmp_aead_tfm_ctx *tfm_ctx =
 			(struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);

 	if (tfm_ctx->fbk_cipher) {
 		crypto_free_aead(tfm_ctx->fbk_cipher);
 		tfm_ctx->fbk_cipher = NULL;
 	}
 	memzero_explicit(tfm_ctx, sizeof(struct zynqmp_aead_tfm_ctx));
 }

 static struct zynqmp_aead_drv_ctx aes_drv_ctx = {
 	.alg.aead.base = {
 		.setkey		= zynqmp_aes_aead_setkey,
 		.setauthsize	= zynqmp_aes_aead_setauthsize,
 		.encrypt	= zynqmp_aes_aead_encrypt,
 		.decrypt	= zynqmp_aes_aead_decrypt,
 		.init		= zynqmp_aes_aead_init,
 		.exit		= zynqmp_aes_aead_exit,
 		.ivsize		= GCM_AES_IV_SIZE,
 		.maxauthsize	= ZYNQMP_AES_AUTH_SIZE,
 		.base = {
 		.cra_name		= "gcm(aes)",
 		.cra_driver_name	= "xilinx-zynqmp-aes-gcm",
 		.cra_priority		= 200,
 		.cra_flags		= CRYPTO_ALG_TYPE_AEAD |
 					  CRYPTO_ALG_ASYNC |
 					  CRYPTO_ALG_ALLOCATES_MEMORY |
 					  CRYPTO_ALG_KERN_DRIVER_ONLY |
 					  CRYPTO_ALG_NEED_FALLBACK,
 		.cra_blocksize		= ZYNQMP_AES_BLK_SIZE,
 		.cra_ctxsize		= sizeof(struct zynqmp_aead_tfm_ctx),
 		.cra_module		= THIS_MODULE,
 		}
 	},
 	.alg.aead.op = {
 		.do_one_request = zynqmp_handle_aes_req,
 	},
 };

 static int zynqmp_aes_aead_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	int err;

 	/* ZynqMP AES driver supports only one instance */
 	if (!aes_drv_ctx.dev)
 		aes_drv_ctx.dev = dev;
 	else
 		return -ENODEV;

 	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(ZYNQMP_DMA_BIT_MASK));
 	if (err < 0) {
 		dev_err(dev, "No usable DMA configuration\n");
 		return err;
 	}

 	aes_drv_ctx.engine = crypto_engine_alloc_init(dev, 1);
 	if (!aes_drv_ctx.engine) {
 		dev_err(dev, "Cannot alloc AES engine\n");
 		err = -ENOMEM;
 		goto err_engine;
 	}

 	err = crypto_engine_start(aes_drv_ctx.engine);
 	if (err) {
 		dev_err(dev, "Cannot start AES engine\n");
 		goto err_engine;
 	}

 	err = crypto_engine_register_aead(&aes_drv_ctx.alg.aead);
 	if (err < 0) {
 		dev_err(dev, "Failed to register AEAD alg.\n");
 		goto err_aead;
 	}
 	return 0;

 err_aead:
 	crypto_engine_unregister_aead(&aes_drv_ctx.alg.aead);

 err_engine:
 	if (aes_drv_ctx.engine)
 		crypto_engine_exit(aes_drv_ctx.engine);

 	return err;
 }

 static void zynqmp_aes_aead_remove(struct platform_device *pdev)
 {
 	crypto_engine_exit(aes_drv_ctx.engine);
 	crypto_engine_unregister_aead(&aes_drv_ctx.alg.aead);
 }

 static const struct of_device_id zynqmp_aes_dt_ids[] = {
 	{ .compatible = "xlnx,zynqmp-aes" },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, zynqmp_aes_dt_ids);

 static struct platform_driver zynqmp_aes_driver = {
 	.probe	= zynqmp_aes_aead_probe,
 	.remove_new = zynqmp_aes_aead_remove,
 	.driver = {
 		.name		= "zynqmp-aes",
 		.of_match_table = zynqmp_aes_dt_ids,
 	},
 };

 module_platform_driver(zynqmp_aes_driver);
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Xilinx ZynqMP AES Driver.
	* Copyright (c) 2020 Xilinx Inc.
	*/

	#include <crypto/aes.h>
	#include <crypto/engine.h>
	#include <crypto/gcm.h>
	#include <crypto/internal/aead.h>
	#include <crypto/scatterwalk.h>
	#include <linux/dma-mapping.h>
	#include <linux/err.h>
	#include <linux/firmware/xlnx-zynqmp.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/mod_devicetable.h>
	#include <linux/platform_device.h>
	#include <linux/string.h>

	#define ZYNQMP_DMA_BIT_MASK 32U

	#define ZYNQMP_AES_KEY_SIZE AES_KEYSIZE_256
	#define ZYNQMP_AES_AUTH_SIZE 16U
	#define ZYNQMP_KEY_SRC_SEL_KEY_LEN 1U
	#define ZYNQMP_AES_BLK_SIZE 1U
	#define ZYNQMP_AES_MIN_INPUT_BLK_SIZE 4U
	#define ZYNQMP_AES_WORD_LEN 4U

	#define ZYNQMP_AES_GCM_TAG_MISMATCH_ERR 0x01
	#define ZYNQMP_AES_WRONG_KEY_SRC_ERR 0x13
	#define ZYNQMP_AES_PUF_NOT_PROGRAMMED 0xE300

	enum zynqmp_aead_op {
	ZYNQMP_AES_DECRYPT = 0,
	ZYNQMP_AES_ENCRYPT
	};

	enum zynqmp_aead_keysrc {
	ZYNQMP_AES_KUP_KEY = 0,
	ZYNQMP_AES_DEV_KEY,
	ZYNQMP_AES_PUF_KEY
	};

	struct zynqmp_aead_drv_ctx {
	union {
	struct aead_engine_alg aead;
	} alg;
	struct device *dev;
	struct crypto_engine *engine;
	};

	struct zynqmp_aead_hw_req {
	u64 src;
	u64 iv;
	u64 key;
	u64 dst;
	u64 size;
	u64 op;
	u64 keysrc;
	};

	struct zynqmp_aead_tfm_ctx {
	struct device *dev;
	u8 key[ZYNQMP_AES_KEY_SIZE];
	u8 *iv;
	u32 keylen;
	u32 authsize;
	enum zynqmp_aead_keysrc keysrc;
	struct crypto_aead *fbk_cipher;
	};

	struct zynqmp_aead_req_ctx {
	enum zynqmp_aead_op op;
	};

	static int zynqmp_aes_aead_cipher(struct aead_request *req)
	{
	struct crypto_aead *aead = crypto_aead_reqtfm(req);
	struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead);
	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
	struct device *dev = tfm_ctx->dev;
	struct zynqmp_aead_hw_req *hwreq;
	dma_addr_t dma_addr_data, dma_addr_hw_req;
	unsigned int data_size;
	unsigned int status;
	int ret;
	size_t dma_size;
	char *kbuf;
	int err;

	if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY)
	dma_size = req->cryptlen + ZYNQMP_AES_KEY_SIZE
	+ GCM_AES_IV_SIZE;
	else
	dma_size = req->cryptlen + GCM_AES_IV_SIZE;

	kbuf = dma_alloc_coherent(dev, dma_size, &dma_addr_data, GFP_KERNEL);
	if (!kbuf)
	return -ENOMEM;

	hwreq = dma_alloc_coherent(dev, sizeof(struct zynqmp_aead_hw_req),
	&dma_addr_hw_req, GFP_KERNEL);
	if (!hwreq) {
	dma_free_coherent(dev, dma_size, kbuf, dma_addr_data);
	return -ENOMEM;
	}

	data_size = req->cryptlen;
	scatterwalk_map_and_copy(kbuf, req->src, 0, req->cryptlen, 0);
	memcpy(kbuf + data_size, req->iv, GCM_AES_IV_SIZE);

	hwreq->src = dma_addr_data;
	hwreq->dst = dma_addr_data;
	hwreq->iv = hwreq->src + data_size;
	hwreq->keysrc = tfm_ctx->keysrc;
	hwreq->op = rq_ctx->op;

	if (hwreq->op == ZYNQMP_AES_ENCRYPT)
	hwreq->size = data_size;
	else
	hwreq->size = data_size - ZYNQMP_AES_AUTH_SIZE;

	if (hwreq->keysrc == ZYNQMP_AES_KUP_KEY) {
	memcpy(kbuf + data_size + GCM_AES_IV_SIZE,
	tfm_ctx->key, ZYNQMP_AES_KEY_SIZE);

	hwreq->key = hwreq->src + data_size + GCM_AES_IV_SIZE;
	} else {
	hwreq->key = 0;
	}

	ret = zynqmp_pm_aes_engine(dma_addr_hw_req, &status);

	if (ret) {
	dev_err(dev, "ERROR: AES PM API failed\n");
	err = ret;
	} else if (status) {
	switch (status) {
	case ZYNQMP_AES_GCM_TAG_MISMATCH_ERR:
	dev_err(dev, "ERROR: Gcm Tag mismatch\n");
	break;
	case ZYNQMP_AES_WRONG_KEY_SRC_ERR:
	dev_err(dev, "ERROR: Wrong KeySrc, enable secure mode\n");
	break;
	case ZYNQMP_AES_PUF_NOT_PROGRAMMED:
	dev_err(dev, "ERROR: PUF is not registered\n");
	break;
	default:
	dev_err(dev, "ERROR: Unknown error\n");
	break;
	}
	err = -status;
	} else {
	if (hwreq->op == ZYNQMP_AES_ENCRYPT)
	data_size = data_size + ZYNQMP_AES_AUTH_SIZE;
	else
	data_size = data_size - ZYNQMP_AES_AUTH_SIZE;

	sg_copy_from_buffer(req->dst, sg_nents(req->dst),
	kbuf, data_size);
	err = 0;
	}

	if (kbuf) {
	memzero_explicit(kbuf, dma_size);
	dma_free_coherent(dev, dma_size, kbuf, dma_addr_data);
	}
	if (hwreq) {
	memzero_explicit(hwreq, sizeof(struct zynqmp_aead_hw_req));
	dma_free_coherent(dev, sizeof(struct zynqmp_aead_hw_req),
	hwreq, dma_addr_hw_req);
	}
	return err;
	}

	static int zynqmp_fallback_check(struct zynqmp_aead_tfm_ctx *tfm_ctx,
	struct aead_request *req)
	{
	int need_fallback = 0;
	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);

	if (tfm_ctx->authsize != ZYNQMP_AES_AUTH_SIZE)
	need_fallback = 1;

	if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY &&
	tfm_ctx->keylen != ZYNQMP_AES_KEY_SIZE) {
	need_fallback = 1;
	}
	if (req->assoclen != 0 \|\|
	req->cryptlen < ZYNQMP_AES_MIN_INPUT_BLK_SIZE) {
	need_fallback = 1;
	}
	if ((req->cryptlen % ZYNQMP_AES_WORD_LEN) != 0)
	need_fallback = 1;

	if (rq_ctx->op == ZYNQMP_AES_DECRYPT &&
	req->cryptlen <= ZYNQMP_AES_AUTH_SIZE) {
	need_fallback = 1;
	}
	return need_fallback;
	}

	static int zynqmp_handle_aes_req(struct crypto_engine *engine,
	void *req)
	{
	struct aead_request *areq =
	container_of(req, struct aead_request, base);
	struct crypto_aead *aead = crypto_aead_reqtfm(req);
	struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead);
	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(areq);
	struct aead_request *subreq = aead_request_ctx(req);
	int need_fallback;
	int err;

	need_fallback = zynqmp_fallback_check(tfm_ctx, areq);

	if (need_fallback) {
	aead_request_set_tfm(subreq, tfm_ctx->fbk_cipher);

	aead_request_set_callback(subreq, areq->base.flags,
	NULL, NULL);
	aead_request_set_crypt(subreq, areq->src, areq->dst,
	areq->cryptlen, areq->iv);
	aead_request_set_ad(subreq, areq->assoclen);
	if (rq_ctx->op == ZYNQMP_AES_ENCRYPT)
	err = crypto_aead_encrypt(subreq);
	else
	err = crypto_aead_decrypt(subreq);
	} else {
	err = zynqmp_aes_aead_cipher(areq);
	}

	local_bh_disable();
	crypto_finalize_aead_request(engine, areq, err);
	local_bh_enable();

	return 0;
	}

	static int zynqmp_aes_aead_setkey(struct crypto_aead aead, const u8 key,
	unsigned int keylen)
	{
	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
	struct zynqmp_aead_tfm_ctx *tfm_ctx =
	(struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
	unsigned char keysrc;

	if (keylen == ZYNQMP_KEY_SRC_SEL_KEY_LEN) {
	keysrc = *key;
	if (keysrc == ZYNQMP_AES_KUP_KEY \|\|
	keysrc == ZYNQMP_AES_DEV_KEY \|\|
	keysrc == ZYNQMP_AES_PUF_KEY) {
	tfm_ctx->keysrc = (enum zynqmp_aead_keysrc)keysrc;
	} else {
	tfm_ctx->keylen = keylen;
	}
	} else {
	tfm_ctx->keylen = keylen;
	if (keylen == ZYNQMP_AES_KEY_SIZE) {
	tfm_ctx->keysrc = ZYNQMP_AES_KUP_KEY;
	memcpy(tfm_ctx->key, key, keylen);
	}
	}

	tfm_ctx->fbk_cipher->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
	tfm_ctx->fbk_cipher->base.crt_flags \|= (aead->base.crt_flags &
	CRYPTO_TFM_REQ_MASK);

	return crypto_aead_setkey(tfm_ctx->fbk_cipher, key, keylen);
	}

	static int zynqmp_aes_aead_setauthsize(struct crypto_aead *aead,
	unsigned int authsize)
	{
	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
	struct zynqmp_aead_tfm_ctx *tfm_ctx =
	(struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);

	tfm_ctx->authsize = authsize;
	return crypto_aead_setauthsize(tfm_ctx->fbk_cipher, authsize);
	}

	static int zynqmp_aes_aead_encrypt(struct aead_request *req)
	{
	struct zynqmp_aead_drv_ctx *drv_ctx;
	struct crypto_aead *aead = crypto_aead_reqtfm(req);
	struct aead_alg *alg = crypto_aead_alg(aead);
	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);

	rq_ctx->op = ZYNQMP_AES_ENCRYPT;
	drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead.base);

	return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req);
	}

	static int zynqmp_aes_aead_decrypt(struct aead_request *req)
	{
	struct zynqmp_aead_drv_ctx *drv_ctx;
	struct crypto_aead *aead = crypto_aead_reqtfm(req);
	struct aead_alg *alg = crypto_aead_alg(aead);
	struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);

	rq_ctx->op = ZYNQMP_AES_DECRYPT;
	drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead.base);

	return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req);
	}

	static int zynqmp_aes_aead_init(struct crypto_aead *aead)
	{
	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
	struct zynqmp_aead_tfm_ctx *tfm_ctx =
	(struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
	struct zynqmp_aead_drv_ctx *drv_ctx;
	struct aead_alg *alg = crypto_aead_alg(aead);

	drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead.base);
	tfm_ctx->dev = drv_ctx->dev;

	tfm_ctx->fbk_cipher = crypto_alloc_aead(drv_ctx->alg.aead.base.base.cra_name,
	0,
	CRYPTO_ALG_NEED_FALLBACK);

	if (IS_ERR(tfm_ctx->fbk_cipher)) {
	pr_err("%s() Error: failed to allocate fallback for %s\n",
	__func__, drv_ctx->alg.aead.base.base.cra_name);
	return PTR_ERR(tfm_ctx->fbk_cipher);
	}

	crypto_aead_set_reqsize(aead,
	max(sizeof(struct zynqmp_aead_req_ctx),
	sizeof(struct aead_request) +
	crypto_aead_reqsize(tfm_ctx->fbk_cipher)));
	return 0;
	}

	static void zynqmp_aes_aead_exit(struct crypto_aead *aead)
	{
	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
	struct zynqmp_aead_tfm_ctx *tfm_ctx =
	(struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);

	if (tfm_ctx->fbk_cipher) {
	crypto_free_aead(tfm_ctx->fbk_cipher);
	tfm_ctx->fbk_cipher = NULL;
	}
	memzero_explicit(tfm_ctx, sizeof(struct zynqmp_aead_tfm_ctx));
	}

	static struct zynqmp_aead_drv_ctx aes_drv_ctx = {
	.alg.aead.base = {
	.setkey = zynqmp_aes_aead_setkey,
	.setauthsize = zynqmp_aes_aead_setauthsize,
	.encrypt = zynqmp_aes_aead_encrypt,
	.decrypt = zynqmp_aes_aead_decrypt,
	.init = zynqmp_aes_aead_init,
	.exit = zynqmp_aes_aead_exit,
	.ivsize = GCM_AES_IV_SIZE,
	.maxauthsize = ZYNQMP_AES_AUTH_SIZE,
	.base = {
	.cra_name = "gcm(aes)",
	.cra_driver_name = "xilinx-zynqmp-aes-gcm",
	.cra_priority = 200,
	.cra_flags = CRYPTO_ALG_TYPE_AEAD \|
	CRYPTO_ALG_ASYNC \|
	CRYPTO_ALG_ALLOCATES_MEMORY \|
	CRYPTO_ALG_KERN_DRIVER_ONLY \|
	CRYPTO_ALG_NEED_FALLBACK,
	.cra_blocksize = ZYNQMP_AES_BLK_SIZE,
	.cra_ctxsize = sizeof(struct zynqmp_aead_tfm_ctx),
	.cra_module = THIS_MODULE,
	}
	},
	.alg.aead.op = {
	.do_one_request = zynqmp_handle_aes_req,
	},
	};

	static int zynqmp_aes_aead_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	int err;

	/* ZynqMP AES driver supports only one instance */
	if (!aes_drv_ctx.dev)
	aes_drv_ctx.dev = dev;
	else
	return -ENODEV;

	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(ZYNQMP_DMA_BIT_MASK));
	if (err < 0) {
	dev_err(dev, "No usable DMA configuration\n");
	return err;
	}

	aes_drv_ctx.engine = crypto_engine_alloc_init(dev, 1);
	if (!aes_drv_ctx.engine) {
	dev_err(dev, "Cannot alloc AES engine\n");
	err = -ENOMEM;
	goto err_engine;
	}

	err = crypto_engine_start(aes_drv_ctx.engine);
	if (err) {
	dev_err(dev, "Cannot start AES engine\n");
	goto err_engine;
	}

	err = crypto_engine_register_aead(&aes_drv_ctx.alg.aead);
	if (err < 0) {
	dev_err(dev, "Failed to register AEAD alg.\n");
	goto err_aead;
	}
	return 0;

	err_aead:
	crypto_engine_unregister_aead(&aes_drv_ctx.alg.aead);

	err_engine:
	if (aes_drv_ctx.engine)
	crypto_engine_exit(aes_drv_ctx.engine);

	return err;
	}

	static void zynqmp_aes_aead_remove(struct platform_device *pdev)
	{
	crypto_engine_exit(aes_drv_ctx.engine);
	crypto_engine_unregister_aead(&aes_drv_ctx.alg.aead);
	}

	static const struct of_device_id zynqmp_aes_dt_ids[] = {
	{ .compatible = "xlnx,zynqmp-aes" },
	{ /* sentinel */ }
	};
	MODULE_DEVICE_TABLE(of, zynqmp_aes_dt_ids);

	static struct platform_driver zynqmp_aes_driver = {
	.probe = zynqmp_aes_aead_probe,
	.remove_new = zynqmp_aes_aead_remove,
	.driver = {
	.name = "zynqmp-aes",
	.of_match_table = zynqmp_aes_dt_ids,
	},
	};

	module_platform_driver(zynqmp_aes_driver);
	MODULE_LICENSE("GPL");