drivers/crypto/geode-aes.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
  /* Copyright (C) 2004-2006, Advanced Micro Devices, Inc.
   */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/pci.h>
 #include <linux/pci_ids.h>
 #include <linux/crypto.h>
 #include <linux/spinlock.h>
 #include <crypto/algapi.h>
 #include <crypto/aes.h>
 #include <crypto/internal/cipher.h>
 #include <crypto/internal/skcipher.h>

 #include <linux/io.h>
 #include <linux/delay.h>

 #include "geode-aes.h"

 /* Static structures */

 static void __iomem *_iobase;
 static DEFINE_SPINLOCK(lock);

 /* Write a 128 bit field (either a writable key or IV) */
 static inline void
 _writefield(u32 offset, const void *value)
 {
 	int i;

 	for (i = 0; i < 4; i++)
 		iowrite32(((const u32 *) value)[i], _iobase + offset + (i * 4));
 }

 /* Read a 128 bit field (either a writable key or IV) */
 static inline void
 _readfield(u32 offset, void *value)
 {
 	int i;

 	for (i = 0; i < 4; i++)
 		((u32 *) value)[i] = ioread32(_iobase + offset + (i * 4));
 }

 static int
 do_crypt(const void *src, void *dst, u32 len, u32 flags)
 {
 	u32 status;
 	u32 counter = AES_OP_TIMEOUT;

 	iowrite32(virt_to_phys((void *)src), _iobase + AES_SOURCEA_REG);
 	iowrite32(virt_to_phys(dst), _iobase + AES_DSTA_REG);
 	iowrite32(len,  _iobase + AES_LENA_REG);

 	/* Start the operation */
 	iowrite32(AES_CTRL_START | flags, _iobase + AES_CTRLA_REG);

 	do {
 		status = ioread32(_iobase + AES_INTR_REG);
 		cpu_relax();
 	} while (!(status & AES_INTRA_PENDING) && --counter);

 	/* Clear the event */
 	iowrite32((status & 0xFF) | AES_INTRA_PENDING, _iobase + AES_INTR_REG);
 	return counter ? 0 : 1;
 }

 static void
 geode_aes_crypt(const struct geode_aes_tfm_ctx *tctx, const void *src,
 		void *dst, u32 len, u8 *iv, int mode, int dir)
 {
 	u32 flags = 0;
 	unsigned long iflags;
 	int ret;

 	/* If the source and destination is the same, then
 	 * we need to turn on the coherent flags, otherwise
 	 * we don't need to worry
 	 */

 	flags |= (AES_CTRL_DCA | AES_CTRL_SCA);

 	if (dir == AES_DIR_ENCRYPT)
 		flags |= AES_CTRL_ENCRYPT;

 	/* Start the critical section */

 	spin_lock_irqsave(&lock, iflags);

 	if (mode == AES_MODE_CBC) {
 		flags |= AES_CTRL_CBC;
 		_writefield(AES_WRITEIV0_REG, iv);
 	}

 	flags |= AES_CTRL_WRKEY;
 	_writefield(AES_WRITEKEY0_REG, tctx->key);

 	ret = do_crypt(src, dst, len, flags);
 	BUG_ON(ret);

 	if (mode == AES_MODE_CBC)
 		_readfield(AES_WRITEIV0_REG, iv);

 	spin_unlock_irqrestore(&lock, iflags);
 }

 /* CRYPTO-API Functions */

 static int geode_setkey_cip(struct crypto_tfm *tfm, const u8 *key,
 		unsigned int len)
 {
 	struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

 	tctx->keylen = len;

 	if (len == AES_KEYSIZE_128) {
 		memcpy(tctx->key, key, len);
 		return 0;
 	}

 	if (len != AES_KEYSIZE_192 && len != AES_KEYSIZE_256)
 		/* not supported at all */
 		return -EINVAL;

 	/*
 	 * The requested key size is not supported by HW, do a fallback
 	 */
 	tctx->fallback.cip->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
 	tctx->fallback.cip->base.crt_flags |=
 		(tfm->crt_flags & CRYPTO_TFM_REQ_MASK);

 	return crypto_cipher_setkey(tctx->fallback.cip, key, len);
 }

 static int geode_setkey_skcipher(struct crypto_skcipher *tfm, const u8 *key,
 				 unsigned int len)
 {
 	struct geode_aes_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);

 	tctx->keylen = len;

 	if (len == AES_KEYSIZE_128) {
 		memcpy(tctx->key, key, len);
 		return 0;
 	}

 	if (len != AES_KEYSIZE_192 && len != AES_KEYSIZE_256)
 		/* not supported at all */
 		return -EINVAL;

 	/*
 	 * The requested key size is not supported by HW, do a fallback
 	 */
 	crypto_skcipher_clear_flags(tctx->fallback.skcipher,
 				    CRYPTO_TFM_REQ_MASK);
 	crypto_skcipher_set_flags(tctx->fallback.skcipher,
 				  crypto_skcipher_get_flags(tfm) &
 				  CRYPTO_TFM_REQ_MASK);
 	return crypto_skcipher_setkey(tctx->fallback.skcipher, key, len);
 }

 static void
 geode_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	const struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

 	if (unlikely(tctx->keylen != AES_KEYSIZE_128)) {
 		crypto_cipher_encrypt_one(tctx->fallback.cip, out, in);
 		return;
 	}

 	geode_aes_crypt(tctx, in, out, AES_BLOCK_SIZE, NULL,
 			AES_MODE_ECB, AES_DIR_ENCRYPT);
 }


 static void
 geode_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
 {
 	const struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

 	if (unlikely(tctx->keylen != AES_KEYSIZE_128)) {
 		crypto_cipher_decrypt_one(tctx->fallback.cip, out, in);
 		return;
 	}

 	geode_aes_crypt(tctx, in, out, AES_BLOCK_SIZE, NULL,
 			AES_MODE_ECB, AES_DIR_DECRYPT);
 }

 static int fallback_init_cip(struct crypto_tfm *tfm)
 {
 	const char *name = crypto_tfm_alg_name(tfm);
 	struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

 	tctx->fallback.cip = crypto_alloc_cipher(name, 0,
 						 CRYPTO_ALG_NEED_FALLBACK);

 	if (IS_ERR(tctx->fallback.cip)) {
 		printk(KERN_ERR "Error allocating fallback algo %s\n", name);
 		return PTR_ERR(tctx->fallback.cip);
 	}

 	return 0;
 }

 static void fallback_exit_cip(struct crypto_tfm *tfm)
 {
 	struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

 	crypto_free_cipher(tctx->fallback.cip);
 }

 static struct crypto_alg geode_alg = {
 	.cra_name			=	"aes",
 	.cra_driver_name	=	"geode-aes",
 	.cra_priority		=	300,
 	.cra_alignmask		=	15,
 	.cra_flags			=	CRYPTO_ALG_TYPE_CIPHER |
 							CRYPTO_ALG_NEED_FALLBACK,
 	.cra_init			=	fallback_init_cip,
 	.cra_exit			=	fallback_exit_cip,
 	.cra_blocksize		=	AES_BLOCK_SIZE,
 	.cra_ctxsize		=	sizeof(struct geode_aes_tfm_ctx),
 	.cra_module			=	THIS_MODULE,
 	.cra_u				=	{
 		.cipher	=	{
 			.cia_min_keysize	=	AES_MIN_KEY_SIZE,
 			.cia_max_keysize	=	AES_MAX_KEY_SIZE,
 			.cia_setkey			=	geode_setkey_cip,
 			.cia_encrypt		=	geode_encrypt,
 			.cia_decrypt		=	geode_decrypt
 		}
 	}
 };

 static int geode_init_skcipher(struct crypto_skcipher *tfm)
 {
 	const char *name = crypto_tfm_alg_name(&tfm->base);
 	struct geode_aes_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);

 	tctx->fallback.skcipher =
 		crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK |
 				      CRYPTO_ALG_ASYNC);
 	if (IS_ERR(tctx->fallback.skcipher)) {
 		printk(KERN_ERR "Error allocating fallback algo %s\n", name);
 		return PTR_ERR(tctx->fallback.skcipher);
 	}

 	crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
 				    crypto_skcipher_reqsize(tctx->fallback.skcipher));
 	return 0;
 }

 static void geode_exit_skcipher(struct crypto_skcipher *tfm)
 {
 	struct geode_aes_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);

 	crypto_free_skcipher(tctx->fallback.skcipher);
 }

 static int geode_skcipher_crypt(struct skcipher_request *req, int mode, int dir)
 {
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	const struct geode_aes_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
 	struct skcipher_walk walk;
 	unsigned int nbytes;
 	int err;

 	if (unlikely(tctx->keylen != AES_KEYSIZE_128)) {
 		struct skcipher_request *subreq = skcipher_request_ctx(req);

 		*subreq = *req;
 		skcipher_request_set_tfm(subreq, tctx->fallback.skcipher);
 		if (dir == AES_DIR_DECRYPT)
 			return crypto_skcipher_decrypt(subreq);
 		else
 			return crypto_skcipher_encrypt(subreq);
 	}

 	err = skcipher_walk_virt(&walk, req, false);

 	while ((nbytes = walk.nbytes) != 0) {
 		geode_aes_crypt(tctx, walk.src.virt.addr, walk.dst.virt.addr,
 				round_down(nbytes, AES_BLOCK_SIZE),
 				walk.iv, mode, dir);
 		err = skcipher_walk_done(&walk, nbytes % AES_BLOCK_SIZE);
 	}

 	return err;
 }

 static int geode_cbc_encrypt(struct skcipher_request *req)
 {
 	return geode_skcipher_crypt(req, AES_MODE_CBC, AES_DIR_ENCRYPT);
 }

 static int geode_cbc_decrypt(struct skcipher_request *req)
 {
 	return geode_skcipher_crypt(req, AES_MODE_CBC, AES_DIR_DECRYPT);
 }

 static int geode_ecb_encrypt(struct skcipher_request *req)
 {
 	return geode_skcipher_crypt(req, AES_MODE_ECB, AES_DIR_ENCRYPT);
 }

 static int geode_ecb_decrypt(struct skcipher_request *req)
 {
 	return geode_skcipher_crypt(req, AES_MODE_ECB, AES_DIR_DECRYPT);
 }

 static struct skcipher_alg geode_skcipher_algs[] = {
 	{
 		.base.cra_name		= "cbc(aes)",
 		.base.cra_driver_name	= "cbc-aes-geode",
 		.base.cra_priority	= 400,
 		.base.cra_flags		= CRYPTO_ALG_KERN_DRIVER_ONLY |
 					  CRYPTO_ALG_NEED_FALLBACK,
 		.base.cra_blocksize	= AES_BLOCK_SIZE,
 		.base.cra_ctxsize	= sizeof(struct geode_aes_tfm_ctx),
 		.base.cra_alignmask	= 15,
 		.base.cra_module	= THIS_MODULE,
 		.init			= geode_init_skcipher,
 		.exit			= geode_exit_skcipher,
 		.setkey			= geode_setkey_skcipher,
 		.encrypt		= geode_cbc_encrypt,
 		.decrypt		= geode_cbc_decrypt,
 		.min_keysize		= AES_MIN_KEY_SIZE,
 		.max_keysize		= AES_MAX_KEY_SIZE,
 		.ivsize			= AES_BLOCK_SIZE,
 	}, {
 		.base.cra_name		= "ecb(aes)",
 		.base.cra_driver_name	= "ecb-aes-geode",
 		.base.cra_priority	= 400,
 		.base.cra_flags		= CRYPTO_ALG_KERN_DRIVER_ONLY |
 					  CRYPTO_ALG_NEED_FALLBACK,
 		.base.cra_blocksize	= AES_BLOCK_SIZE,
 		.base.cra_ctxsize	= sizeof(struct geode_aes_tfm_ctx),
 		.base.cra_alignmask	= 15,
 		.base.cra_module	= THIS_MODULE,
 		.init			= geode_init_skcipher,
 		.exit			= geode_exit_skcipher,
 		.setkey			= geode_setkey_skcipher,
 		.encrypt		= geode_ecb_encrypt,
 		.decrypt		= geode_ecb_decrypt,
 		.min_keysize		= AES_MIN_KEY_SIZE,
 		.max_keysize		= AES_MAX_KEY_SIZE,
 	},
 };

 static void geode_aes_remove(struct pci_dev *dev)
 {
 	crypto_unregister_alg(&geode_alg);
 	crypto_unregister_skciphers(geode_skcipher_algs,
 				    ARRAY_SIZE(geode_skcipher_algs));

 	pci_iounmap(dev, _iobase);
 	_iobase = NULL;

 	pci_release_regions(dev);
 	pci_disable_device(dev);
 }


 static int geode_aes_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
 	int ret;

 	ret = pci_enable_device(dev);
 	if (ret)
 		return ret;

 	ret = pci_request_regions(dev, "geode-aes");
 	if (ret)
 		goto eenable;

 	_iobase = pci_iomap(dev, 0, 0);

 	if (_iobase == NULL) {
 		ret = -ENOMEM;
 		goto erequest;
 	}

 	/* Clear any pending activity */
 	iowrite32(AES_INTR_PENDING | AES_INTR_MASK, _iobase + AES_INTR_REG);

 	ret = crypto_register_alg(&geode_alg);
 	if (ret)
 		goto eiomap;

 	ret = crypto_register_skciphers(geode_skcipher_algs,
 					ARRAY_SIZE(geode_skcipher_algs));
 	if (ret)
 		goto ealg;

 	dev_notice(&dev->dev, "GEODE AES engine enabled.\n");
 	return 0;

  ealg:
 	crypto_unregister_alg(&geode_alg);

  eiomap:
 	pci_iounmap(dev, _iobase);

  erequest:
 	pci_release_regions(dev);

  eenable:
 	pci_disable_device(dev);

 	dev_err(&dev->dev, "GEODE AES initialization failed.\n");
 	return ret;
 }

 static struct pci_device_id geode_aes_tbl[] = {
 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_LX_AES), },
 	{ 0, }
 };

 MODULE_DEVICE_TABLE(pci, geode_aes_tbl);

 static struct pci_driver geode_aes_driver = {
 	.name = "Geode LX AES",
 	.id_table = geode_aes_tbl,
 	.probe = geode_aes_probe,
 	.remove = geode_aes_remove,
 };

 module_pci_driver(geode_aes_driver);

 MODULE_AUTHOR("Advanced Micro Devices, Inc.");
 MODULE_DESCRIPTION("Geode LX Hardware AES driver");
 MODULE_LICENSE("GPL");
 MODULE_IMPORT_NS(CRYPTO_INTERNAL);
	// SPDX-License-Identifier: GPL-2.0-or-later
	/* Copyright (C) 2004-2006, Advanced Micro Devices, Inc.
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/pci.h>
	#include <linux/pci_ids.h>
	#include <linux/crypto.h>
	#include <linux/spinlock.h>
	#include <crypto/algapi.h>
	#include <crypto/aes.h>
	#include <crypto/internal/cipher.h>
	#include <crypto/internal/skcipher.h>

	#include <linux/io.h>
	#include <linux/delay.h>

	#include "geode-aes.h"

	/* Static structures */

	static void __iomem *_iobase;
	static DEFINE_SPINLOCK(lock);

	/* Write a 128 bit field (either a writable key or IV) */
	static inline void
	_writefield(u32 offset, const void *value)
	{
	int i;

	for (i = 0; i < 4; i++)
	iowrite32(((const u32 ) value)[i], _iobase + offset + (i 4));
	}

	/* Read a 128 bit field (either a writable key or IV) */
	static inline void
	_readfield(u32 offset, void *value)
	{
	int i;

	for (i = 0; i < 4; i++)
	((u32 ) value)[i] = ioread32(_iobase + offset + (i 4));
	}

	static int
	do_crypt(const void src, void dst, u32 len, u32 flags)
	{
	u32 status;
	u32 counter = AES_OP_TIMEOUT;

	iowrite32(virt_to_phys((void *)src), _iobase + AES_SOURCEA_REG);
	iowrite32(virt_to_phys(dst), _iobase + AES_DSTA_REG);
	iowrite32(len, _iobase + AES_LENA_REG);

	/* Start the operation */
	iowrite32(AES_CTRL_START \| flags, _iobase + AES_CTRLA_REG);

	do {
	status = ioread32(_iobase + AES_INTR_REG);
	cpu_relax();
	} while (!(status & AES_INTRA_PENDING) && --counter);

	/* Clear the event */
	iowrite32((status & 0xFF) \| AES_INTRA_PENDING, _iobase + AES_INTR_REG);
	return counter ? 0 : 1;
	}

	static void
	geode_aes_crypt(const struct geode_aes_tfm_ctx tctx, const void src,
	void dst, u32 len, u8 iv, int mode, int dir)
	{
	u32 flags = 0;
	unsigned long iflags;
	int ret;

	/* If the source and destination is the same, then
	* we need to turn on the coherent flags, otherwise
	* we don't need to worry
	*/

	flags \|= (AES_CTRL_DCA \| AES_CTRL_SCA);

	if (dir == AES_DIR_ENCRYPT)
	flags \|= AES_CTRL_ENCRYPT;

	/* Start the critical section */

	spin_lock_irqsave(&lock, iflags);

	if (mode == AES_MODE_CBC) {
	flags \|= AES_CTRL_CBC;
	_writefield(AES_WRITEIV0_REG, iv);
	}

	flags \|= AES_CTRL_WRKEY;
	_writefield(AES_WRITEKEY0_REG, tctx->key);

	ret = do_crypt(src, dst, len, flags);
	BUG_ON(ret);

	if (mode == AES_MODE_CBC)
	_readfield(AES_WRITEIV0_REG, iv);

	spin_unlock_irqrestore(&lock, iflags);
	}

	/* CRYPTO-API Functions */

	static int geode_setkey_cip(struct crypto_tfm tfm, const u8 key,
	unsigned int len)
	{
	struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

	tctx->keylen = len;

	if (len == AES_KEYSIZE_128) {
	memcpy(tctx->key, key, len);
	return 0;
	}

	if (len != AES_KEYSIZE_192 && len != AES_KEYSIZE_256)
	/* not supported at all */
	return -EINVAL;

	/*
	* The requested key size is not supported by HW, do a fallback
	*/
	tctx->fallback.cip->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
	tctx->fallback.cip->base.crt_flags \|=
	(tfm->crt_flags & CRYPTO_TFM_REQ_MASK);

	return crypto_cipher_setkey(tctx->fallback.cip, key, len);
	}

	static int geode_setkey_skcipher(struct crypto_skcipher tfm, const u8 key,
	unsigned int len)
	{
	struct geode_aes_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);

	tctx->keylen = len;

	if (len == AES_KEYSIZE_128) {
	memcpy(tctx->key, key, len);
	return 0;
	}

	if (len != AES_KEYSIZE_192 && len != AES_KEYSIZE_256)
	/* not supported at all */
	return -EINVAL;

	/*
	* The requested key size is not supported by HW, do a fallback
	*/
	crypto_skcipher_clear_flags(tctx->fallback.skcipher,
	CRYPTO_TFM_REQ_MASK);
	crypto_skcipher_set_flags(tctx->fallback.skcipher,
	crypto_skcipher_get_flags(tfm) &
	CRYPTO_TFM_REQ_MASK);
	return crypto_skcipher_setkey(tctx->fallback.skcipher, key, len);
	}

	static void
	geode_encrypt(struct crypto_tfm tfm, u8 out, const u8 *in)
	{
	const struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

	if (unlikely(tctx->keylen != AES_KEYSIZE_128)) {
	crypto_cipher_encrypt_one(tctx->fallback.cip, out, in);
	return;
	}

	geode_aes_crypt(tctx, in, out, AES_BLOCK_SIZE, NULL,
	AES_MODE_ECB, AES_DIR_ENCRYPT);
	}


	static void
	geode_decrypt(struct crypto_tfm tfm, u8 out, const u8 *in)
	{
	const struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

	if (unlikely(tctx->keylen != AES_KEYSIZE_128)) {
	crypto_cipher_decrypt_one(tctx->fallback.cip, out, in);
	return;
	}

	geode_aes_crypt(tctx, in, out, AES_BLOCK_SIZE, NULL,
	AES_MODE_ECB, AES_DIR_DECRYPT);
	}

	static int fallback_init_cip(struct crypto_tfm *tfm)
	{
	const char *name = crypto_tfm_alg_name(tfm);
	struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

	tctx->fallback.cip = crypto_alloc_cipher(name, 0,
	CRYPTO_ALG_NEED_FALLBACK);

	if (IS_ERR(tctx->fallback.cip)) {
	printk(KERN_ERR "Error allocating fallback algo %s\n", name);
	return PTR_ERR(tctx->fallback.cip);
	}

	return 0;
	}

	static void fallback_exit_cip(struct crypto_tfm *tfm)
	{
	struct geode_aes_tfm_ctx *tctx = crypto_tfm_ctx(tfm);

	crypto_free_cipher(tctx->fallback.cip);
	}

	static struct crypto_alg geode_alg = {
	.cra_name = "aes",
	.cra_driver_name = "geode-aes",
	.cra_priority = 300,
	.cra_alignmask = 15,
	.cra_flags = CRYPTO_ALG_TYPE_CIPHER \|
	CRYPTO_ALG_NEED_FALLBACK,
	.cra_init = fallback_init_cip,
	.cra_exit = fallback_exit_cip,
	.cra_blocksize = AES_BLOCK_SIZE,
	.cra_ctxsize = sizeof(struct geode_aes_tfm_ctx),
	.cra_module = THIS_MODULE,
	.cra_u = {
	.cipher = {
	.cia_min_keysize = AES_MIN_KEY_SIZE,
	.cia_max_keysize = AES_MAX_KEY_SIZE,
	.cia_setkey = geode_setkey_cip,
	.cia_encrypt = geode_encrypt,
	.cia_decrypt = geode_decrypt
	}
	}
	};

	static int geode_init_skcipher(struct crypto_skcipher *tfm)
	{
	const char *name = crypto_tfm_alg_name(&tfm->base);
	struct geode_aes_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);

	tctx->fallback.skcipher =
	crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK \|
	CRYPTO_ALG_ASYNC);
	if (IS_ERR(tctx->fallback.skcipher)) {
	printk(KERN_ERR "Error allocating fallback algo %s\n", name);
	return PTR_ERR(tctx->fallback.skcipher);
	}

	crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
	crypto_skcipher_reqsize(tctx->fallback.skcipher));
	return 0;
	}

	static void geode_exit_skcipher(struct crypto_skcipher *tfm)
	{
	struct geode_aes_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);

	crypto_free_skcipher(tctx->fallback.skcipher);
	}

	static int geode_skcipher_crypt(struct skcipher_request *req, int mode, int dir)
	{
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
	const struct geode_aes_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
	struct skcipher_walk walk;
	unsigned int nbytes;
	int err;

	if (unlikely(tctx->keylen != AES_KEYSIZE_128)) {
	struct skcipher_request *subreq = skcipher_request_ctx(req);

	subreq = req;
	skcipher_request_set_tfm(subreq, tctx->fallback.skcipher);
	if (dir == AES_DIR_DECRYPT)
	return crypto_skcipher_decrypt(subreq);
	else
	return crypto_skcipher_encrypt(subreq);
	}

	err = skcipher_walk_virt(&walk, req, false);

	while ((nbytes = walk.nbytes) != 0) {
	geode_aes_crypt(tctx, walk.src.virt.addr, walk.dst.virt.addr,
	round_down(nbytes, AES_BLOCK_SIZE),
	walk.iv, mode, dir);
	err = skcipher_walk_done(&walk, nbytes % AES_BLOCK_SIZE);
	}

	return err;
	}

	static int geode_cbc_encrypt(struct skcipher_request *req)
	{
	return geode_skcipher_crypt(req, AES_MODE_CBC, AES_DIR_ENCRYPT);
	}

	static int geode_cbc_decrypt(struct skcipher_request *req)
	{
	return geode_skcipher_crypt(req, AES_MODE_CBC, AES_DIR_DECRYPT);
	}

	static int geode_ecb_encrypt(struct skcipher_request *req)
	{
	return geode_skcipher_crypt(req, AES_MODE_ECB, AES_DIR_ENCRYPT);
	}

	static int geode_ecb_decrypt(struct skcipher_request *req)
	{
	return geode_skcipher_crypt(req, AES_MODE_ECB, AES_DIR_DECRYPT);
	}

	static struct skcipher_alg geode_skcipher_algs[] = {
	{
	.base.cra_name = "cbc(aes)",
	.base.cra_driver_name = "cbc-aes-geode",
	.base.cra_priority = 400,
	.base.cra_flags = CRYPTO_ALG_KERN_DRIVER_ONLY \|
	CRYPTO_ALG_NEED_FALLBACK,
	.base.cra_blocksize = AES_BLOCK_SIZE,
	.base.cra_ctxsize = sizeof(struct geode_aes_tfm_ctx),
	.base.cra_alignmask = 15,
	.base.cra_module = THIS_MODULE,
	.init = geode_init_skcipher,
	.exit = geode_exit_skcipher,
	.setkey = geode_setkey_skcipher,
	.encrypt = geode_cbc_encrypt,
	.decrypt = geode_cbc_decrypt,
	.min_keysize = AES_MIN_KEY_SIZE,
	.max_keysize = AES_MAX_KEY_SIZE,
	.ivsize = AES_BLOCK_SIZE,
	}, {
	.base.cra_name = "ecb(aes)",
	.base.cra_driver_name = "ecb-aes-geode",
	.base.cra_priority = 400,
	.base.cra_flags = CRYPTO_ALG_KERN_DRIVER_ONLY \|
	CRYPTO_ALG_NEED_FALLBACK,
	.base.cra_blocksize = AES_BLOCK_SIZE,
	.base.cra_ctxsize = sizeof(struct geode_aes_tfm_ctx),
	.base.cra_alignmask = 15,
	.base.cra_module = THIS_MODULE,
	.init = geode_init_skcipher,
	.exit = geode_exit_skcipher,
	.setkey = geode_setkey_skcipher,
	.encrypt = geode_ecb_encrypt,
	.decrypt = geode_ecb_decrypt,
	.min_keysize = AES_MIN_KEY_SIZE,
	.max_keysize = AES_MAX_KEY_SIZE,
	},
	};

	static void geode_aes_remove(struct pci_dev *dev)
	{
	crypto_unregister_alg(&geode_alg);
	crypto_unregister_skciphers(geode_skcipher_algs,
	ARRAY_SIZE(geode_skcipher_algs));

	pci_iounmap(dev, _iobase);
	_iobase = NULL;

	pci_release_regions(dev);
	pci_disable_device(dev);
	}


	static int geode_aes_probe(struct pci_dev dev, const struct pci_device_id id)
	{
	int ret;

	ret = pci_enable_device(dev);
	if (ret)
	return ret;

	ret = pci_request_regions(dev, "geode-aes");
	if (ret)
	goto eenable;

	_iobase = pci_iomap(dev, 0, 0);

	if (_iobase == NULL) {
	ret = -ENOMEM;
	goto erequest;
	}

	/* Clear any pending activity */
	iowrite32(AES_INTR_PENDING \| AES_INTR_MASK, _iobase + AES_INTR_REG);

	ret = crypto_register_alg(&geode_alg);
	if (ret)
	goto eiomap;

	ret = crypto_register_skciphers(geode_skcipher_algs,
	ARRAY_SIZE(geode_skcipher_algs));
	if (ret)
	goto ealg;

	dev_notice(&dev->dev, "GEODE AES engine enabled.\n");
	return 0;

	ealg:
	crypto_unregister_alg(&geode_alg);

	eiomap:
	pci_iounmap(dev, _iobase);

	erequest:
	pci_release_regions(dev);

	eenable:
	pci_disable_device(dev);

	dev_err(&dev->dev, "GEODE AES initialization failed.\n");
	return ret;
	}

	static struct pci_device_id geode_aes_tbl[] = {
	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_LX_AES), },
	{ 0, }
	};

	MODULE_DEVICE_TABLE(pci, geode_aes_tbl);

	static struct pci_driver geode_aes_driver = {
	.name = "Geode LX AES",
	.id_table = geode_aes_tbl,
	.probe = geode_aes_probe,
	.remove = geode_aes_remove,
	};

	module_pci_driver(geode_aes_driver);

	MODULE_AUTHOR("Advanced Micro Devices, Inc.");
	MODULE_DESCRIPTION("Geode LX Hardware AES driver");
	MODULE_LICENSE("GPL");
	MODULE_IMPORT_NS(CRYPTO_INTERNAL);