crypto: stm32 - Support for STM32 CRYP crypto module

This module registers block cipher algorithms that make use of the
STMicroelectronics STM32 crypto "CRYP1" hardware.
The following algorithms are supported:
- aes: ecb, cbc, ctr
- des: ecb, cbc
- tdes: ecb, cbc
Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/stm32/Kconfig

@@ -18,3 +18,12 @@ config HASH_DEV_STM32
 	help
           This enables support for the HASH hw accelerator which can be found
 	  on STMicroelectronics STM32 SOC.
+
+config CRYP_DEV_STM32
+	tristate "Support for STM32 cryp accelerators"
+	depends on ARCH_STM32
+	select CRYPTO_HASH
+	select CRYPTO_ENGINE
+	help
+          This enables support for the CRYP (AES/DES/TDES) hw accelerator which
+	  can be found on STMicroelectronics STM32 SOC.

drivers/crypto/stm32/Makefile

 obj-$(CONFIG_CRC_DEV_STM32) += stm32_crc32.o
-obj-$(CONFIG_HASH_DEV_STM32) += stm32-hash.o
+obj-$(CONFIG_HASH_DEV_STM32) += stm32-hash.o
\ No newline at end of file
+obj-$(CONFIG_CRYP_DEV_STM32) += stm32-cryp.o

drivers/crypto/stm32/stm32-cryp.c

+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ * Author: Fabien Dessenne <fabien.dessenne@st.com>
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+#include <crypto/aes.h>
+#include <crypto/des.h>
+#include <crypto/engine.h>
+#include <crypto/scatterwalk.h>
+
+#define DRIVER_NAME             "stm32-cryp"
+
+/* Bit [0] encrypt / decrypt */
+#define FLG_ENCRYPT             BIT(0)
+/* Bit [8..1] algo & operation mode */
+#define FLG_AES                 BIT(1)
+#define FLG_DES                 BIT(2)
+#define FLG_TDES                BIT(3)
+#define FLG_ECB                 BIT(4)
+#define FLG_CBC                 BIT(5)
+#define FLG_CTR                 BIT(6)
+/* Mode mask = bits [15..0] */
+#define FLG_MODE_MASK           GENMASK(15, 0)
+
+/* Registers */
+#define CRYP_CR                 0x00000000
+#define CRYP_SR                 0x00000004
+#define CRYP_DIN                0x00000008
+#define CRYP_DOUT               0x0000000C
+#define CRYP_DMACR              0x00000010
+#define CRYP_IMSCR              0x00000014
+#define CRYP_RISR               0x00000018
+#define CRYP_MISR               0x0000001C
+#define CRYP_K0LR               0x00000020
+#define CRYP_K0RR               0x00000024
+#define CRYP_K1LR               0x00000028
+#define CRYP_K1RR               0x0000002C
+#define CRYP_K2LR               0x00000030
+#define CRYP_K2RR               0x00000034
+#define CRYP_K3LR               0x00000038
+#define CRYP_K3RR               0x0000003C
+#define CRYP_IV0LR              0x00000040
+#define CRYP_IV0RR              0x00000044
+#define CRYP_IV1LR              0x00000048
+#define CRYP_IV1RR              0x0000004C
+
+/* Registers values */
+#define CR_DEC_NOT_ENC          0x00000004
+#define CR_TDES_ECB             0x00000000
+#define CR_TDES_CBC             0x00000008
+#define CR_DES_ECB              0x00000010
+#define CR_DES_CBC              0x00000018
+#define CR_AES_ECB              0x00000020
+#define CR_AES_CBC              0x00000028
+#define CR_AES_CTR              0x00000030
+#define CR_AES_KP               0x00000038
+#define CR_AES_UNKNOWN          0xFFFFFFFF
+#define CR_ALGO_MASK            0x00080038
+#define CR_DATA32               0x00000000
+#define CR_DATA16               0x00000040
+#define CR_DATA8                0x00000080
+#define CR_DATA1                0x000000C0
+#define CR_KEY128               0x00000000
+#define CR_KEY192               0x00000100
+#define CR_KEY256               0x00000200
+#define CR_FFLUSH               0x00004000
+#define CR_CRYPEN               0x00008000
+
+#define SR_BUSY                 0x00000010
+#define SR_OFNE                 0x00000004
+
+#define IMSCR_IN                BIT(0)
+#define IMSCR_OUT               BIT(1)
+
+#define MISR_IN                 BIT(0)
+#define MISR_OUT                BIT(1)
+
+/* Misc */
+#define AES_BLOCK_32            (AES_BLOCK_SIZE / sizeof(u32))
+#define _walked_in              (cryp->in_walk.offset - cryp->in_sg->offset)
+#define _walked_out             (cryp->out_walk.offset - cryp->out_sg->offset)
+
+struct stm32_cryp_ctx {
+	struct stm32_cryp       *cryp;
+	int                     keylen;
+	u32                     key[AES_KEYSIZE_256 / sizeof(u32)];
+	unsigned long           flags;
+};
+
+struct stm32_cryp_reqctx {
+	unsigned long mode;
+};
+
+struct stm32_cryp {
+	struct list_head        list;
+	struct device           *dev;
+	void __iomem            *regs;
+	struct clk              *clk;
+	unsigned long           flags;
+	u32                     irq_status;
+	struct stm32_cryp_ctx   *ctx;
+
+	struct crypto_engine    *engine;
+
+	struct mutex            lock; /* protects req */
+	struct ablkcipher_request *req;
+
+	size_t                  hw_blocksize;
+
+	size_t                  total_in;
+	size_t                  total_in_save;
+	size_t                  total_out;
+	size_t                  total_out_save;
+
+	struct scatterlist      *in_sg;
+	struct scatterlist      *out_sg;
+	struct scatterlist      *out_sg_save;
+
+	struct scatterlist      in_sgl;
+	struct scatterlist      out_sgl;
+	bool                    sgs_copied;
+
+	int                     in_sg_len;
+	int                     out_sg_len;
+
+	struct scatter_walk     in_walk;
+	struct scatter_walk     out_walk;
+
+	u32                     last_ctr[4];
+};
+
+struct stm32_cryp_list {
+	struct list_head        dev_list;
+	spinlock_t              lock; /* protect dev_list */
+};
+
+static struct stm32_cryp_list cryp_list = {
+	.dev_list = LIST_HEAD_INIT(cryp_list.dev_list),
+	.lock     = __SPIN_LOCK_UNLOCKED(cryp_list.lock),
+};
+
+static inline bool is_aes(struct stm32_cryp *cryp)
+{
+	return cryp->flags & FLG_AES;
+}
+
+static inline bool is_des(struct stm32_cryp *cryp)
+{
+	return cryp->flags & FLG_DES;
+}
+
+static inline bool is_tdes(struct stm32_cryp *cryp)
+{
+	return cryp->flags & FLG_TDES;
+}
+
+static inline bool is_ecb(struct stm32_cryp *cryp)
+{
+	return cryp->flags & FLG_ECB;
+}
+
+static inline bool is_cbc(struct stm32_cryp *cryp)
+{
+	return cryp->flags & FLG_CBC;
+}
+
+static inline bool is_ctr(struct stm32_cryp *cryp)
+{
+	return cryp->flags & FLG_CTR;
+}
+
+static inline bool is_encrypt(struct stm32_cryp *cryp)
+{
+	return cryp->flags & FLG_ENCRYPT;
+}
+
+static inline bool is_decrypt(struct stm32_cryp *cryp)
+{
+	return !is_encrypt(cryp);
+}
+
+static inline u32 stm32_cryp_read(struct stm32_cryp *cryp, u32 ofst)
+{
+	return readl_relaxed(cryp->regs + ofst);
+}
+
+static inline void stm32_cryp_write(struct stm32_cryp *cryp, u32 ofst, u32 val)
+{
+	writel_relaxed(val, cryp->regs + ofst);
+}
+
+static inline int stm32_cryp_wait_busy(struct stm32_cryp *cryp)
+{
+	u32 status;
+
+	return readl_relaxed_poll_timeout(cryp->regs + CRYP_SR, status,
+			!(status & SR_BUSY), 10, 100000);
+}
+
+static struct stm32_cryp *stm32_cryp_find_dev(struct stm32_cryp_ctx *ctx)
+{
+	struct stm32_cryp *tmp, *cryp = NULL;
+
+	spin_lock_bh(&cryp_list.lock);
+	if (!ctx->cryp) {
+		list_for_each_entry(tmp, &cryp_list.dev_list, list) {
+			cryp = tmp;
+			break;
+		}
+		ctx->cryp = cryp;
+	} else {
+		cryp = ctx->cryp;
+	}
+
+	spin_unlock_bh(&cryp_list.lock);
+
+	return cryp;
+}
+
+static int stm32_cryp_check_aligned(struct scatterlist *sg, size_t total,
+				    size_t align)
+{
+	int len = 0;
+
+	if (!total)
+		return 0;
+
+	if (!IS_ALIGNED(total, align))
+		return -EINVAL;
+
+	while (sg) {
+		if (!IS_ALIGNED(sg->offset, sizeof(u32)))
+			return -EINVAL;
+
+		if (!IS_ALIGNED(sg->length, align))
+			return -EINVAL;
+
+		len += sg->length;
+		sg = sg_next(sg);
+	}
+
+	if (len != total)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int stm32_cryp_check_io_aligned(struct stm32_cryp *cryp)
+{
+	int ret;
+
+	ret = stm32_cryp_check_aligned(cryp->in_sg, cryp->total_in,
+				       cryp->hw_blocksize);
+	if (ret)
+		return ret;
+
+	ret = stm32_cryp_check_aligned(cryp->out_sg, cryp->total_out,
+				       cryp->hw_blocksize);
+
+	return ret;
+}
+
+static void sg_copy_buf(void *buf, struct scatterlist *sg,
+			unsigned int start, unsigned int nbytes, int out)
+{
+	struct scatter_walk walk;
+
+	if (!nbytes)
+		return;
+
+	scatterwalk_start(&walk, sg);
+	scatterwalk_advance(&walk, start);
+	scatterwalk_copychunks(buf, &walk, nbytes, out);
+	scatterwalk_done(&walk, out, 0);
+}
+
+static int stm32_cryp_copy_sgs(struct stm32_cryp *cryp)
+{
+	void *buf_in, *buf_out;
+	int pages, total_in, total_out;
+
+	if (!stm32_cryp_check_io_aligned(cryp)) {
+		cryp->sgs_copied = 0;
+		return 0;
+	}
+
+	total_in = ALIGN(cryp->total_in, cryp->hw_blocksize);
+	pages = total_in ? get_order(total_in) : 1;
+	buf_in = (void *)__get_free_pages(GFP_ATOMIC, pages);
+
+	total_out = ALIGN(cryp->total_out, cryp->hw_blocksize);
+	pages = total_out ? get_order(total_out) : 1;
+	buf_out = (void *)__get_free_pages(GFP_ATOMIC, pages);
+
+	if (!buf_in || !buf_out) {
+		dev_err(cryp->dev, "Can't allocate pages when unaligned\n");
+		cryp->sgs_copied = 0;
+		return -EFAULT;
+	}
+
+	sg_copy_buf(buf_in, cryp->in_sg, 0, cryp->total_in, 0);
+
+	sg_init_one(&cryp->in_sgl, buf_in, total_in);
+	cryp->in_sg = &cryp->in_sgl;
+	cryp->in_sg_len = 1;
+
+	sg_init_one(&cryp->out_sgl, buf_out, total_out);
+	cryp->out_sg_save = cryp->out_sg;
+	cryp->out_sg = &cryp->out_sgl;
+	cryp->out_sg_len = 1;
+
+	cryp->sgs_copied = 1;
+
+	return 0;
+}
+
+static void stm32_cryp_hw_write_iv(struct stm32_cryp *cryp, u32 *iv)
+{
+	if (!iv)
+		return;
+
+	stm32_cryp_write(cryp, CRYP_IV0LR, cpu_to_be32(*iv++));
+	stm32_cryp_write(cryp, CRYP_IV0RR, cpu_to_be32(*iv++));
+
+	if (is_aes(cryp)) {
+		stm32_cryp_write(cryp, CRYP_IV1LR, cpu_to_be32(*iv++));
+		stm32_cryp_write(cryp, CRYP_IV1RR, cpu_to_be32(*iv++));
+	}
+}
+
+static void stm32_cryp_hw_write_key(struct stm32_cryp *c)
+{
+	unsigned int i;
+	int r_id;
+
+	if (is_des(c)) {
+		stm32_cryp_write(c, CRYP_K1LR, cpu_to_be32(c->ctx->key[0]));
+		stm32_cryp_write(c, CRYP_K1RR, cpu_to_be32(c->ctx->key[1]));
+	} else {
+		r_id = CRYP_K3RR;
+		for (i = c->ctx->keylen / sizeof(u32); i > 0; i--, r_id -= 4)
+			stm32_cryp_write(c, r_id,
+					 cpu_to_be32(c->ctx->key[i - 1]));
+	}
+}
+
+static u32 stm32_cryp_get_hw_mode(struct stm32_cryp *cryp)
+{
+	if (is_aes(cryp) && is_ecb(cryp))
+		return CR_AES_ECB;
+
+	if (is_aes(cryp) && is_cbc(cryp))
+		return CR_AES_CBC;
+
+	if (is_aes(cryp) && is_ctr(cryp))
+		return CR_AES_CTR;
+
+	if (is_des(cryp) && is_ecb(cryp))
+		return CR_DES_ECB;
+
+	if (is_des(cryp) && is_cbc(cryp))
+		return CR_DES_CBC;
+
+	if (is_tdes(cryp) && is_ecb(cryp))
+		return CR_TDES_ECB;
+
+	if (is_tdes(cryp) && is_cbc(cryp))
+		return CR_TDES_CBC;
+
+	dev_err(cryp->dev, "Unknown mode\n");
+	return CR_AES_UNKNOWN;
+}
+
+static int stm32_cryp_hw_init(struct stm32_cryp *cryp)
+{
+	int ret;
+	u32 cfg, hw_mode;
+
+	/* Disable interrupt */
+	stm32_cryp_write(cryp, CRYP_IMSCR, 0);
+
+	/* Set key */
+	stm32_cryp_hw_write_key(cryp);
+
+	/* Set configuration */
+	cfg = CR_DATA8 | CR_FFLUSH;
+
+	switch (cryp->ctx->keylen) {
+	case AES_KEYSIZE_128:
+		cfg |= CR_KEY128;
+		break;
+
+	case AES_KEYSIZE_192:
+		cfg |= CR_KEY192;
+		break;
+
+	default:
+	case AES_KEYSIZE_256:
+		cfg |= CR_KEY256;
+		break;
+	}
+
+	hw_mode = stm32_cryp_get_hw_mode(cryp);
+	if (hw_mode == CR_AES_UNKNOWN)
+		return -EINVAL;
+
+	/* AES ECB/CBC decrypt: run key preparation first */
+	if (is_decrypt(cryp) &&
+	    ((hw_mode == CR_AES_ECB) || (hw_mode == CR_AES_CBC))) {
+		stm32_cryp_write(cryp, CRYP_CR, cfg | CR_AES_KP | CR_CRYPEN);
+
+		/* Wait for end of processing */
+		ret = stm32_cryp_wait_busy(cryp);
+		if (ret) {
+			dev_err(cryp->dev, "Timeout (key preparation)\n");
+			return ret;
+		}
+	}
+
+	cfg |= hw_mode;
+
+	if (is_decrypt(cryp))
+		cfg |= CR_DEC_NOT_ENC;
+
+	/* Apply config and flush (valid when CRYPEN = 0) */
+	stm32_cryp_write(cryp, CRYP_CR, cfg);
+
+	switch (hw_mode) {
+	case CR_DES_CBC:
+	case CR_TDES_CBC:
+	case CR_AES_CBC:
+	case CR_AES_CTR:
+		stm32_cryp_hw_write_iv(cryp, (u32 *)cryp->req->info);
+		break;
+
+	default:
+		break;
+	}
+
+	/* Enable now */
+	cfg |= CR_CRYPEN;
+
+	stm32_cryp_write(cryp, CRYP_CR, cfg);
+
+	return 0;
+}
+
+static void stm32_cryp_finish_req(struct stm32_cryp *cryp)
+{
+	int err = 0;
+
+	if (cryp->sgs_copied) {
+		void *buf_in, *buf_out;
+		int pages, len;
+
+		buf_in = sg_virt(&cryp->in_sgl);
+		buf_out = sg_virt(&cryp->out_sgl);
+
+		sg_copy_buf(buf_out, cryp->out_sg_save, 0,
+			    cryp->total_out_save, 1);
+
+		len = ALIGN(cryp->total_in_save, cryp->hw_blocksize);
+		pages = len ? get_order(len) : 1;
+		free_pages((unsigned long)buf_in, pages);
+
+		len = ALIGN(cryp->total_out_save, cryp->hw_blocksize);
+		pages = len ? get_order(len) : 1;
+		free_pages((unsigned long)buf_out, pages);
+	}
+
+	crypto_finalize_cipher_request(cryp->engine, cryp->req, err);
+	cryp->req = NULL;
+
+	memset(cryp->ctx->key, 0, cryp->ctx->keylen);
+
+	mutex_unlock(&cryp->lock);
+}
+
+static int stm32_cryp_cpu_start(struct stm32_cryp *cryp)
+{
+	/* Enable interrupt and let the IRQ handler do everything */
+	stm32_cryp_write(cryp, CRYP_IMSCR, IMSCR_IN | IMSCR_OUT);
+
+	return 0;
+}
+
+static int stm32_cryp_cra_init(struct crypto_tfm *tfm)
+{
+	tfm->crt_ablkcipher.reqsize = sizeof(struct stm32_cryp_reqctx);
+
+	return 0;
+}
+
+static int stm32_cryp_crypt(struct ablkcipher_request *req, unsigned long mode)
+{
+	struct stm32_cryp_ctx *ctx = crypto_ablkcipher_ctx(
+			crypto_ablkcipher_reqtfm(req));
+	struct stm32_cryp_reqctx *rctx = ablkcipher_request_ctx(req);
+	struct stm32_cryp *cryp = stm32_cryp_find_dev(ctx);
+
+	if (!cryp)
+		return -ENODEV;
+
+	rctx->mode = mode;
+
+	return crypto_transfer_cipher_request_to_engine(cryp->engine, req);
+}
+
+static int stm32_cryp_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+			     unsigned int keylen)
+{
+	struct stm32_cryp_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+
+	memcpy(ctx->key, key, keylen);
+	ctx->keylen = keylen;
+
+	return 0;
+}
+
+static int stm32_cryp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+				 unsigned int keylen)
+{
+	if (keylen != AES_KEYSIZE_128 && keylen != AES_KEYSIZE_192 &&
+	    keylen != AES_KEYSIZE_256)
+		return -EINVAL;
+	else
+		return stm32_cryp_setkey(tfm, key, keylen);
+}
+
+static int stm32_cryp_des_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+				 unsigned int keylen)
+{
+	if (keylen != DES_KEY_SIZE)
+		return -EINVAL;
+	else
+		return stm32_cryp_setkey(tfm, key, keylen);
+}
+
+static int stm32_cryp_tdes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+				  unsigned int keylen)
+{
+	if (keylen != (3 * DES_KEY_SIZE))
+		return -EINVAL;
+	else
+		return stm32_cryp_setkey(tfm, key, keylen);
+}
+
+static int stm32_cryp_aes_ecb_encrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_AES | FLG_ECB | FLG_ENCRYPT);
+}
+
+static int stm32_cryp_aes_ecb_decrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_AES | FLG_ECB);
+}
+
+static int stm32_cryp_aes_cbc_encrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_AES | FLG_CBC | FLG_ENCRYPT);
+}
+
+static int stm32_cryp_aes_cbc_decrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_AES | FLG_CBC);
+}
+
+static int stm32_cryp_aes_ctr_encrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_AES | FLG_CTR | FLG_ENCRYPT);
+}
+
+static int stm32_cryp_aes_ctr_decrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_AES | FLG_CTR);
+}
+
+static int stm32_cryp_des_ecb_encrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_DES | FLG_ECB | FLG_ENCRYPT);
+}
+
+static int stm32_cryp_des_ecb_decrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_DES | FLG_ECB);
+}
+
+static int stm32_cryp_des_cbc_encrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_DES | FLG_CBC | FLG_ENCRYPT);
+}
+
+static int stm32_cryp_des_cbc_decrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_DES | FLG_CBC);
+}
+
+static int stm32_cryp_tdes_ecb_encrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_TDES | FLG_ECB | FLG_ENCRYPT);
+}
+
+static int stm32_cryp_tdes_ecb_decrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_TDES | FLG_ECB);
+}
+
+static int stm32_cryp_tdes_cbc_encrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_TDES | FLG_CBC | FLG_ENCRYPT);
+}
+
+static int stm32_cryp_tdes_cbc_decrypt(struct ablkcipher_request *req)
+{
+	return stm32_cryp_crypt(req, FLG_TDES | FLG_CBC);
+}
+
+static int stm32_cryp_prepare_req(struct crypto_engine *engine,
+				  struct ablkcipher_request *req)
+{
+	struct stm32_cryp_ctx *ctx;
+	struct stm32_cryp *cryp;
+	struct stm32_cryp_reqctx *rctx;
+	int ret;
+
+	if (!req)
+		return -EINVAL;
+
+	ctx = crypto_ablkcipher_ctx(crypto_ablkcipher_reqtfm(req));
+
+	cryp = ctx->cryp;
+
+	if (!cryp)
+		return -ENODEV;
+
+	mutex_lock(&cryp->lock);
+
+	rctx = ablkcipher_request_ctx(req);
+	rctx->mode &= FLG_MODE_MASK;
+
+	ctx->cryp = cryp;
+
+	cryp->flags = (cryp->flags & ~FLG_MODE_MASK) | rctx->mode;
+	cryp->hw_blocksize = is_aes(cryp) ? AES_BLOCK_SIZE : DES_BLOCK_SIZE;
+	cryp->ctx = ctx;
+
+	cryp->req = req;
+	cryp->total_in = req->nbytes;
+	cryp->total_out = cryp->total_in;
+
+	cryp->total_in_save = cryp->total_in;
+	cryp->total_out_save = cryp->total_out;
+
+	cryp->in_sg = req->src;
+	cryp->out_sg = req->dst;
+	cryp->out_sg_save = cryp->out_sg;
+
+	cryp->in_sg_len = sg_nents_for_len(cryp->in_sg, cryp->total_in);
+	if (cryp->in_sg_len < 0) {
+		dev_err(cryp->dev, "Cannot get in_sg_len\n");
+		ret = cryp->in_sg_len;
+		goto out;
+	}
+
+	cryp->out_sg_len = sg_nents_for_len(cryp->out_sg, cryp->total_out);
+	if (cryp->out_sg_len < 0) {
+		dev_err(cryp->dev, "Cannot get out_sg_len\n");
+		ret = cryp->out_sg_len;
+		goto out;
+	}
+
+	ret = stm32_cryp_copy_sgs(cryp);
+	if (ret)
+		goto out;
+
+	scatterwalk_start(&cryp->in_walk, cryp->in_sg);
+	scatterwalk_start(&cryp->out_walk, cryp->out_sg);
+
+	ret = stm32_cryp_hw_init(cryp);
+out:
+	if (ret)
+		mutex_unlock(&cryp->lock);
+
+	return ret;
+}
+
+static int stm32_cryp_prepare_cipher_req(struct crypto_engine *engine,
+					 struct ablkcipher_request *req)
+{
+	return stm32_cryp_prepare_req(engine, req);
+}
+
+static int stm32_cryp_cipher_one_req(struct crypto_engine *engine,
+				     struct ablkcipher_request *req)
+{
+	struct stm32_cryp_ctx *ctx = crypto_ablkcipher_ctx(
+			crypto_ablkcipher_reqtfm(req));
+	struct stm32_cryp *cryp = ctx->cryp;
+
+	if (!cryp)
+		return -ENODEV;
+
+	return stm32_cryp_cpu_start(cryp);
+}
+
+static u32 *stm32_cryp_next_out(struct stm32_cryp *cryp, u32 *dst,
+				unsigned int n)
+{
+	scatterwalk_advance(&cryp->out_walk, n);
+
+	if (unlikely(cryp->out_sg->length == _walked_out)) {
+		cryp->out_sg = sg_next(cryp->out_sg);
+		if (cryp->out_sg) {
+			scatterwalk_start(&cryp->out_walk, cryp->out_sg);
+			return (sg_virt(cryp->out_sg) + _walked_out);
+		}
+	}
+
+	return (u32 *)((u8 *)dst + n);
+}
+
+static u32 *stm32_cryp_next_in(struct stm32_cryp *cryp, u32 *src,
+			       unsigned int n)
+{
+	scatterwalk_advance(&cryp->in_walk, n);
+
+	if (unlikely(cryp->in_sg->length == _walked_in)) {
+		cryp->in_sg = sg_next(cryp->in_sg);
+		if (cryp->in_sg) {
+			scatterwalk_start(&cryp->in_walk, cryp->in_sg);
+			return (sg_virt(cryp->in_sg) + _walked_in);
+		}
+	}
+
+	return (u32 *)((u8 *)src + n);
+}
+
+static void stm32_cryp_check_ctr_counter(struct stm32_cryp *cryp)
+{
+	u32 cr;
+
+	if (unlikely(cryp->last_ctr[3] == 0xFFFFFFFF)) {
+		cryp->last_ctr[3] = 0;
+		cryp->last_ctr[2]++;
+		if (!cryp->last_ctr[2]) {
+			cryp->last_ctr[1]++;
+			if (!cryp->last_ctr[1])
+				cryp->last_ctr[0]++;
+		}
+
+		cr = stm32_cryp_read(cryp, CRYP_CR);
+		stm32_cryp_write(cryp, CRYP_CR, cr & ~CR_CRYPEN);
+
+		stm32_cryp_hw_write_iv(cryp, (u32 *)cryp->last_ctr);
+
+		stm32_cryp_write(cryp, CRYP_CR, cr);
+	}
+
+	cryp->last_ctr[0] = stm32_cryp_read(cryp, CRYP_IV0LR);
+	cryp->last_ctr[1] = stm32_cryp_read(cryp, CRYP_IV0RR);
+	cryp->last_ctr[2] = stm32_cryp_read(cryp, CRYP_IV1LR);
+	cryp->last_ctr[3] = stm32_cryp_read(cryp, CRYP_IV1RR);
+}
+
+static bool stm32_cryp_irq_read_data(struct stm32_cryp *cryp)
+{
+	unsigned int i, j;
+	u32 d32, *dst;
+	u8 *d8;
+
+	dst = sg_virt(cryp->out_sg) + _walked_out;
+
+	for (i = 0; i < cryp->hw_blocksize / sizeof(u32); i++) {
+		if (likely(cryp->total_out >= sizeof(u32))) {
+			/* Read a full u32 */
+			*dst = stm32_cryp_read(cryp, CRYP_DOUT);
+
+			dst = stm32_cryp_next_out(cryp, dst, sizeof(u32));
+			cryp->total_out -= sizeof(u32);
+		} else if (!cryp->total_out) {
+			/* Empty fifo out (data from input padding) */
+			d32 = stm32_cryp_read(cryp, CRYP_DOUT);
+		} else {
+			/* Read less than an u32 */
+			d32 = stm32_cryp_read(cryp, CRYP_DOUT);
+			d8 = (u8 *)&d32;
+
+			for (j = 0; j < cryp->total_out; j++) {
+				*((u8 *)dst) = *(d8++);
+				dst = stm32_cryp_next_out(cryp, dst, 1);
+			}
+			cryp->total_out = 0;
+		}
+	}
+
+	return !cryp->total_out || !cryp->total_in;
+}
+
+static void stm32_cryp_irq_write_block(struct stm32_cryp *cryp)
+{
+	unsigned int i, j;
+	u32 *src;
+	u8 d8[4];
+
+	src = sg_virt(cryp->in_sg) + _walked_in;
+
+	for (i = 0; i < cryp->hw_blocksize / sizeof(u32); i++) {
+		if (likely(cryp->total_in >= sizeof(u32))) {
+			/* Write a full u32 */
+			stm32_cryp_write(cryp, CRYP_DIN, *src);
+
+			src = stm32_cryp_next_in(cryp, src, sizeof(u32));
+			cryp->total_in -= sizeof(u32);
+		} else if (!cryp->total_in) {
+			/* Write padding data */
+			stm32_cryp_write(cryp, CRYP_DIN, 0);
+		} else {
+			/* Write less than an u32 */
+			memset(d8, 0, sizeof(u32));
+			for (j = 0; j < cryp->total_in; j++) {
+				d8[j] = *((u8 *)src);
+				src = stm32_cryp_next_in(cryp, src, 1);
+			}
+
+			stm32_cryp_write(cryp, CRYP_DIN, *(u32 *)d8);
+			cryp->total_in = 0;
+		}
+	}
+}
+
+static void stm32_cryp_irq_write_data(struct stm32_cryp *cryp)
+{
+	if (unlikely(!cryp->total_in)) {
+		dev_warn(cryp->dev, "No more data to process\n");
+		return;
+	}
+
+	if (is_aes(cryp) && is_ctr(cryp))
+		stm32_cryp_check_ctr_counter(cryp);
+
+	stm32_cryp_irq_write_block(cryp);
+}
+
+static irqreturn_t stm32_cryp_irq_thread(int irq, void *arg)
+{
+	struct stm32_cryp *cryp = arg;
+
+	if (cryp->irq_status & MISR_OUT)
+		/* Output FIFO IRQ: read data */
+		if (unlikely(stm32_cryp_irq_read_data(cryp))) {
+			/* All bytes processed, finish */
+			stm32_cryp_write(cryp, CRYP_IMSCR, 0);
+			stm32_cryp_finish_req(cryp);
+			return IRQ_HANDLED;
+		}
+
+	if (cryp->irq_status & MISR_IN) {
+		/* Input FIFO IRQ: write data */
+		stm32_cryp_irq_write_data(cryp);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t stm32_cryp_irq(int irq, void *arg)
+{
+	struct stm32_cryp *cryp = arg;
+
+	cryp->irq_status = stm32_cryp_read(cryp, CRYP_MISR);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static struct crypto_alg crypto_algs[] = {
+{
+	.cra_name		= "ecb(aes)",
+	.cra_driver_name	= "stm32-ecb-aes",
+	.cra_priority		= 200,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
+				  CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= AES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct stm32_cryp_ctx),
+	.cra_alignmask		= 0xf,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_init		= stm32_cryp_cra_init,
+	.cra_ablkcipher = {
+		.min_keysize	= AES_MIN_KEY_SIZE,
+		.max_keysize	= AES_MAX_KEY_SIZE,
+		.setkey		= stm32_cryp_aes_setkey,
+		.encrypt	= stm32_cryp_aes_ecb_encrypt,
+		.decrypt	= stm32_cryp_aes_ecb_decrypt,
+	}
+},
+{
+	.cra_name		= "cbc(aes)",
+	.cra_driver_name	= "stm32-cbc-aes",
+	.cra_priority		= 200,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
+				  CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= AES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct stm32_cryp_ctx),
+	.cra_alignmask		= 0xf,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_init		= stm32_cryp_cra_init,
+	.cra_ablkcipher = {
+		.min_keysize	= AES_MIN_KEY_SIZE,
+		.max_keysize	= AES_MAX_KEY_SIZE,
+		.ivsize		= AES_BLOCK_SIZE,
+		.setkey		= stm32_cryp_aes_setkey,
+		.encrypt	= stm32_cryp_aes_cbc_encrypt,
+		.decrypt	= stm32_cryp_aes_cbc_decrypt,
+	}
+},
+{
+	.cra_name		= "ctr(aes)",
+	.cra_driver_name	= "stm32-ctr-aes",
+	.cra_priority		= 200,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
+				  CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= 1,
+	.cra_ctxsize		= sizeof(struct stm32_cryp_ctx),
+	.cra_alignmask		= 0xf,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_init		= stm32_cryp_cra_init,
+	.cra_ablkcipher = {
+		.min_keysize	= AES_MIN_KEY_SIZE,
+		.max_keysize	= AES_MAX_KEY_SIZE,
+		.ivsize		= AES_BLOCK_SIZE,
+		.setkey		= stm32_cryp_aes_setkey,
+		.encrypt	= stm32_cryp_aes_ctr_encrypt,
+		.decrypt	= stm32_cryp_aes_ctr_decrypt,
+	}
+},
+{
+	.cra_name		= "ecb(des)",
+	.cra_driver_name	= "stm32-ecb-des",
+	.cra_priority		= 200,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
+				  CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= DES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct stm32_cryp_ctx),
+	.cra_alignmask		= 0xf,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_init		= stm32_cryp_cra_init,
+	.cra_ablkcipher = {
+		.min_keysize	= DES_BLOCK_SIZE,
+		.max_keysize	= DES_BLOCK_SIZE,
+		.setkey		= stm32_cryp_des_setkey,
+		.encrypt	= stm32_cryp_des_ecb_encrypt,
+		.decrypt	= stm32_cryp_des_ecb_decrypt,
+	}
+},
+{
+	.cra_name		= "cbc(des)",
+	.cra_driver_name	= "stm32-cbc-des",
+	.cra_priority		= 200,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
+				  CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= DES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct stm32_cryp_ctx),
+	.cra_alignmask		= 0xf,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_init		= stm32_cryp_cra_init,
+	.cra_ablkcipher = {
+		.min_keysize	= DES_BLOCK_SIZE,
+		.max_keysize	= DES_BLOCK_SIZE,
+		.ivsize		= DES_BLOCK_SIZE,
+		.setkey		= stm32_cryp_des_setkey,
+		.encrypt	= stm32_cryp_des_cbc_encrypt,
+		.decrypt	= stm32_cryp_des_cbc_decrypt,
+	}
+},
+{
+	.cra_name		= "ecb(des3_ede)",
+	.cra_driver_name	= "stm32-ecb-des3",
+	.cra_priority		= 200,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
+				  CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= DES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct stm32_cryp_ctx),
+	.cra_alignmask		= 0xf,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_init		= stm32_cryp_cra_init,
+	.cra_ablkcipher = {
+		.min_keysize	= 3 * DES_BLOCK_SIZE,
+		.max_keysize	= 3 * DES_BLOCK_SIZE,
+		.setkey		= stm32_cryp_tdes_setkey,
+		.encrypt	= stm32_cryp_tdes_ecb_encrypt,
+		.decrypt	= stm32_cryp_tdes_ecb_decrypt,
+	}
+},
+{
+	.cra_name		= "cbc(des3_ede)",
+	.cra_driver_name	= "stm32-cbc-des3",
+	.cra_priority		= 200,
+	.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
+				  CRYPTO_ALG_ASYNC,
+	.cra_blocksize		= DES_BLOCK_SIZE,
+	.cra_ctxsize		= sizeof(struct stm32_cryp_ctx),
+	.cra_alignmask		= 0xf,
+	.cra_type		= &crypto_ablkcipher_type,
+	.cra_module		= THIS_MODULE,
+	.cra_init		= stm32_cryp_cra_init,
+	.cra_ablkcipher = {
+		.min_keysize	= 3 * DES_BLOCK_SIZE,
+		.max_keysize	= 3 * DES_BLOCK_SIZE,
+		.ivsize		= DES_BLOCK_SIZE,
+		.setkey		= stm32_cryp_tdes_setkey,
+		.encrypt	= stm32_cryp_tdes_cbc_encrypt,
+		.decrypt	= stm32_cryp_tdes_cbc_decrypt,
+	}
+},
+};
+
+static const struct of_device_id stm32_dt_ids[] = {
+	{ .compatible = "st,stm32f756-cryp", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, sti_dt_ids);
+
+static int stm32_cryp_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct stm32_cryp *cryp;
+	struct resource *res;
+	struct reset_control *rst;
+	int irq, ret;
+
+	cryp = devm_kzalloc(dev, sizeof(*cryp), GFP_KERNEL);
+	if (!cryp)
+		return -ENOMEM;
+
+	cryp->dev = dev;
+
+	mutex_init(&cryp->lock);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	cryp->regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(cryp->regs)) {
+		dev_err(dev, "Cannot map CRYP IO\n");
+		return PTR_ERR(cryp->regs);
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "Cannot get IRQ resource\n");
+		return irq;
+	}
+
+	ret = devm_request_threaded_irq(dev, irq, stm32_cryp_irq,
+					stm32_cryp_irq_thread, IRQF_ONESHOT,
+					dev_name(dev), cryp);
+	if (ret) {
+		dev_err(dev, "Cannot grab IRQ\n");
+		return ret;
+	}
+
+	cryp->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(cryp->clk)) {
+		dev_err(dev, "Could not get clock\n");
+		return PTR_ERR(cryp->clk);
+	}
+
+	ret = clk_prepare_enable(cryp->clk);
+	if (ret) {
+		dev_err(cryp->dev, "Failed to enable clock\n");
+		return ret;
+	}
+
+	rst = devm_reset_control_get(dev, NULL);
+	if (!IS_ERR(rst)) {
+		reset_control_assert(rst);
+		udelay(2);
+		reset_control_deassert(rst);
+	}
+
+	platform_set_drvdata(pdev, cryp);
+
+	spin_lock(&cryp_list.lock);
+	list_add(&cryp->list, &cryp_list.dev_list);
+	spin_unlock(&cryp_list.lock);
+
+	/* Initialize crypto engine */
+	cryp->engine = crypto_engine_alloc_init(dev, 1);
+	if (!cryp->engine) {
+		dev_err(dev, "Could not init crypto engine\n");
+		ret = -ENOMEM;
+		goto err_engine1;
+	}
+
+	cryp->engine->prepare_cipher_request = stm32_cryp_prepare_cipher_req;
+	cryp->engine->cipher_one_request = stm32_cryp_cipher_one_req;
+
+	ret = crypto_engine_start(cryp->engine);
+	if (ret) {
+		dev_err(dev, "Could not start crypto engine\n");
+		goto err_engine2;
+	}
+
+	ret = crypto_register_algs(crypto_algs, ARRAY_SIZE(crypto_algs));
+	if (ret) {
+		dev_err(dev, "Could not register algs\n");
+		goto err_algs;
+	}
+
+	dev_info(dev, "Initialized\n");
+
+	return 0;
+
+err_algs:
+err_engine2:
+	crypto_engine_exit(cryp->engine);
+err_engine1:
+	spin_lock(&cryp_list.lock);
+	list_del(&cryp->list);
+	spin_unlock(&cryp_list.lock);
+
+	clk_disable_unprepare(cryp->clk);
+
+	return ret;
+}
+
+static int stm32_cryp_remove(struct platform_device *pdev)
+{
+	struct stm32_cryp *cryp = platform_get_drvdata(pdev);
+
+	if (!cryp)
+		return -ENODEV;
+
+	crypto_unregister_algs(crypto_algs, ARRAY_SIZE(crypto_algs));
+
+	crypto_engine_exit(cryp->engine);
+
+	spin_lock(&cryp_list.lock);
+	list_del(&cryp->list);
+	spin_unlock(&cryp_list.lock);
+
+	clk_disable_unprepare(cryp->clk);
+
+	return 0;
+}
+
+static struct platform_driver stm32_cryp_driver = {
+	.probe  = stm32_cryp_probe,
+	.remove = stm32_cryp_remove,
+	.driver = {
+		.name           = DRIVER_NAME,
+		.of_match_table = stm32_dt_ids,
+	},
+};
+
+module_platform_driver(stm32_cryp_driver);
+
+MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
+MODULE_DESCRIPTION("STMicrolectronics STM32 CRYP hardware driver");
+MODULE_LICENSE("GPL");