[PATCH V2 4/4] crypto: Add Xilinx AES driver

Kalyani Akula
2019-09-01T13:55:39Z

This patch adds AES driver support for the Xilinx
ZynqMP SoC.

Signed-off-by: Kalyani Akula <kalyani.akula@xilinx.com>
---
drivers/crypto/Kconfig | 11 ++
drivers/crypto/Makefile | 1 +
drivers/crypto/zynqmp-aes-gcm.c | 297 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 309 insertions(+)
create mode 100644 drivers/crypto/zynqmp-aes-gcm.c

diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 603413f..a0d058a 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -677,6 +677,17 @@ config CRYPTO_DEV_ROCKCHIP
This driver interfaces with the hardware crypto accelerator.
Supporting cbc/ecb chainmode, and aes/des/des3_ede cipher mode.

+config CRYPTO_DEV_ZYNQMP_AES
+ tristate "Support for Xilinx ZynqMP AES hw accelerator"
+ depends on ARCH_ZYNQMP || COMPILE_TEST
+ select CRYPTO_AES
+ select CRYPTO_SKCIPHER
+ help
+ Xilinx ZynqMP has AES-GCM engine used for symmetric key
+ encryption and decryption. This driver interfaces with AES hw
+ accelerator. Select this if you want to use the ZynqMP module
+ for AES algorithms.
+
config CRYPTO_DEV_MEDIATEK
tristate "MediaTek's EIP97 Cryptographic Engine driver"
depends on (ARM && ARCH_MEDIATEK) || COMPILE_TEST
diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
index afc4753..c99663a 100644
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -48,3 +48,4 @@ obj-$(CONFIG_CRYPTO_DEV_BCM_SPU) += bcm/
obj-$(CONFIG_CRYPTO_DEV_SAFEXCEL) += inside-secure/
obj-$(CONFIG_CRYPTO_DEV_ARTPEC6) += axis/
obj-y += hisilicon/
+obj-$(CONFIG_CRYPTO_DEV_ZYNQMP_AES) += zynqmp-aes-gcm.o
diff --git a/drivers/crypto/zynqmp-aes-gcm.c b/drivers/crypto/zynqmp-aes-gcm.c
new file mode 100644
index 0000000..d65f038
--- /dev/null
+++ b/drivers/crypto/zynqmp-aes-gcm.c
@@ -0,0 +1,297 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx ZynqMP AES Driver.
+ * Copyright (c) 2019 Xilinx Inc.
+ */
+
+#include <crypto/aes.h>
+#include <crypto/scatterwalk.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/scatterlist.h>
+#include <linux/firmware/xlnx-zynqmp.h>
+
+#define ZYNQMP_AES_IV_SIZE 12
+#define ZYNQMP_AES_GCM_SIZE 16
+#define ZYNQMP_AES_KEY_SIZE 32
+
+#define ZYNQMP_AES_DECRYPT 0
+#define ZYNQMP_AES_ENCRYPT 1
+
+#define ZYNQMP_AES_KUP_KEY 0
+#define ZYNQMP_AES_DEVICE_KEY 1
+#define ZYNQMP_AES_PUF_KEY 2
+
+#define ZYNQMP_AES_GCM_TAG_MISMATCH_ERR 0x01
+#define ZYNQMP_AES_SIZE_ERR 0x06
+#define ZYNQMP_AES_WRONG_KEY_SRC_ERR 0x13
+#define ZYNQMP_AES_PUF_NOT_PROGRAMMED 0xE300
+
+#define ZYNQMP_AES_BLOCKSIZE 0x04
+
+static const struct zynqmp_eemi_ops *eemi_ops;
+struct zynqmp_aes_dev *aes_dd;
+
+struct zynqmp_aes_dev {
+ struct device *dev;
+};
+
+struct zynqmp_aes_op {
+ struct zynqmp_aes_dev *dd;
+ void *src;
+ void *dst;
+ int len;
+ u8 key[ZYNQMP_AES_KEY_SIZE];
+ u8 *iv;
+ u32 keylen;
+ u32 keytype;
+};
+
+struct zynqmp_aes_data {
+ u64 src;
+ u64 iv;
+ u64 key;
+ u64 dst;
+ u64 size;
+ u64 optype;
+ u64 keysrc;
+};
+
+static int zynqmp_setkey_blk(struct crypto_tfm *tfm, const u8 *key,
+ unsigned int len)
+{
+ struct zynqmp_aes_op *op = crypto_tfm_ctx(tfm);
+
+ if (((len != 1) && (len != ZYNQMP_AES_KEY_SIZE)) || (!key))
+ return -EINVAL;
+
+ if (len == 1) {
+ op->keytype = *key;
+
+ if ((op->keytype < ZYNQMP_AES_KUP_KEY) ||
+ (op->keytype > ZYNQMP_AES_PUF_KEY))
+ return -EINVAL;
+
+ } else if (len == ZYNQMP_AES_KEY_SIZE) {
+ op->keytype = ZYNQMP_AES_KUP_KEY;
+ op->keylen = len;
+ memcpy(op->key, key, len);
+ }
+
+ return 0;
+}
+
+static int zynqmp_aes_xcrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes,
+ unsigned int flags)
+{
+ struct zynqmp_aes_op *op = crypto_blkcipher_ctx(desc->tfm);
+ struct zynqmp_aes_dev *dd = aes_dd;
+ int err, ret, copy_bytes, src_data = 0, dst_data = 0;
+ dma_addr_t dma_addr, dma_addr_buf;
+ struct zynqmp_aes_data *abuf;
+ struct blkcipher_walk walk;
+ unsigned int data_size;
+ size_t dma_size;
+ char *kbuf;
+
+ if (!eemi_ops->aes)
+ return -ENOTSUPP;
+
+ if (op->keytype == ZYNQMP_AES_KUP_KEY)
+ dma_size = nbytes + ZYNQMP_AES_KEY_SIZE
+ + ZYNQMP_AES_IV_SIZE;
+ else
+ dma_size = nbytes + ZYNQMP_AES_IV_SIZE;
+
+ kbuf = dma_alloc_coherent(dd->dev, dma_size, &dma_addr, GFP_KERNEL);
+ if (!kbuf)
+ return -ENOMEM;
+
+ abuf = dma_alloc_coherent(dd->dev, sizeof(struct zynqmp_aes_data),
+ &dma_addr_buf, GFP_KERNEL);
+ if (!abuf) {
+ dma_free_coherent(dd->dev, dma_size, kbuf, dma_addr);
+ return -ENOMEM;
+ }
+
+ data_size = nbytes;
+ blkcipher_walk_init(&walk, dst, src, data_size);
+ err = blkcipher_walk_virt(desc, &walk);
+ op->iv = walk.iv;
+
+ while ((nbytes = walk.nbytes)) {
+ op->src = walk.src.virt.addr;
+ memcpy(kbuf + src_data, op->src, nbytes);
+ src_data = src_data + nbytes;
+ nbytes &= (ZYNQMP_AES_BLOCKSIZE - 1);
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+ memcpy(kbuf + data_size, op->iv, ZYNQMP_AES_IV_SIZE);
+ abuf->src = dma_addr;
+ abuf->dst = dma_addr;
+ abuf->iv = abuf->src + data_size;
+ abuf->size = data_size - ZYNQMP_AES_GCM_SIZE;
+ abuf->optype = flags;
+ abuf->keysrc = op->keytype;
+
+ if (op->keytype == ZYNQMP_AES_KUP_KEY) {
+ memcpy(kbuf + data_size + ZYNQMP_AES_IV_SIZE,
+ op->key, ZYNQMP_AES_KEY_SIZE);
+
+ abuf->key = abuf->src + data_size + ZYNQMP_AES_IV_SIZE;
+ } else {
+ abuf->key = 0;
+ }
+ eemi_ops->aes(dma_addr_buf, &ret);
+
+ if (ret != 0) {
+ switch (ret) {
+ case ZYNQMP_AES_GCM_TAG_MISMATCH_ERR:
+ dev_err(dd->dev, "ERROR: Gcm Tag mismatch\n\r");
+ break;
+ case ZYNQMP_AES_SIZE_ERR:
+ dev_err(dd->dev, "ERROR : Non word aligned data\n\r");
+ break;
+ case ZYNQMP_AES_WRONG_KEY_SRC_ERR:
+ dev_err(dd->dev, "ERROR: Wrong KeySrc, enable secure mode\n\r");
+ break;
+ case ZYNQMP_AES_PUF_NOT_PROGRAMMED:
+ dev_err(dd->dev, "ERROR: PUF is not registered\r\n");
+ break;
+ default:
+ dev_err(dd->dev, "ERROR: Invalid");
+ break;
+ }
+ goto END;
+ }
+ if (flags)
+ copy_bytes = data_size;
+ else
+ copy_bytes = data_size - ZYNQMP_AES_GCM_SIZE;
+
+ blkcipher_walk_init(&walk, dst, src, copy_bytes);
+ err = blkcipher_walk_virt(desc, &walk);
+
+ while ((nbytes = walk.nbytes)) {
+ memcpy(walk.dst.virt.addr, kbuf + dst_data, nbytes);
+ dst_data = dst_data + nbytes;
+ nbytes &= (ZYNQMP_AES_BLOCKSIZE - 1);
+ err = blkcipher_walk_done(desc, &walk, nbytes);
+ }
+END:
+ memset(kbuf, 0, dma_size);
+ memset(abuf, 0, sizeof(struct zynqmp_aes_data));
+ dma_free_coherent(dd->dev, dma_size, kbuf, dma_addr);
+ dma_free_coherent(dd->dev, sizeof(struct zynqmp_aes_data),
+ abuf, dma_addr_buf);
+ return err;
+}
+
+static int zynqmp_aes_decrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes)
+{
+ return zynqmp_aes_xcrypt(desc, dst, src, nbytes, ZYNQMP_AES_DECRYPT);
+}
+
+static int zynqmp_aes_encrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src,
+ unsigned int nbytes)
+{
+ return zynqmp_aes_xcrypt(desc, dst, src, nbytes, ZYNQMP_AES_ENCRYPT);
+}
+
+static struct crypto_alg zynqmp_alg = {
+ .cra_name = "xilinx-zynqmp-aes",
+ .cra_driver_name = "zynqmp-aes-gcm",
+ .cra_priority = 400,
+ .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
+ CRYPTO_ALG_KERN_DRIVER_ONLY,
+ .cra_blocksize = ZYNQMP_AES_BLOCKSIZE,
+ .cra_ctxsize = sizeof(struct zynqmp_aes_op),
+ .cra_alignmask = 15,
+ .cra_type = &crypto_blkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_u = {
+ .blkcipher = {
+ .min_keysize = 0,
+ .max_keysize = ZYNQMP_AES_KEY_SIZE,
+ .setkey = zynqmp_setkey_blk,
+ .encrypt = zynqmp_aes_encrypt,
+ .decrypt = zynqmp_aes_decrypt,
+ .ivsize = ZYNQMP_AES_IV_SIZE,
+ }
+ }
+};
+
+static const struct of_device_id zynqmp_aes_dt_ids[] = {
+ { .compatible = "xlnx,zynqmp-aes" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, zynqmp_aes_dt_ids);
+
+static int zynqmp_aes_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ eemi_ops = zynqmp_pm_get_eemi_ops();
+
+ if (IS_ERR(eemi_ops))
+ return PTR_ERR(eemi_ops);
+
+ aes_dd = devm_kzalloc(dev, sizeof(*aes_dd), GFP_KERNEL);
+ if (!aes_dd)
+ return -ENOMEM;
+
+ aes_dd->dev = dev;
+ platform_set_drvdata(pdev, aes_dd);
+
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(44));
+ if (ret < 0) {
+ dev_err(dev, "no usable DMA configuration");
+ return ret;
+ }
+
+ ret = crypto_register_alg(&zynqmp_alg);
+ if (ret)
+ goto err_algs;
+
+ dev_info(dev, "AES Successfully Registered\n\r");
+ return 0;
+
+err_algs:
+ return ret;
+}
+
+static int zynqmp_aes_remove(struct platform_device *pdev)
+{
+ aes_dd = platform_get_drvdata(pdev);
+ if (!aes_dd)
+ return -ENODEV;
+ crypto_unregister_alg(&zynqmp_alg);
+
+ return 0;
+}
+
+static struct platform_driver xilinx_aes_driver = {
+ .probe = zynqmp_aes_probe,
+ .remove = zynqmp_aes_remove,
+ .driver = {
+ .name = "zynqmp_aes",
+ .of_match_table = of_match_ptr(zynqmp_aes_dt_ids),
+ },
+};
+
+module_platform_driver(xilinx_aes_driver);
+
+MODULE_DESCRIPTION("Xilinx ZynqMP AES hw acceleration support.");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Nava kishore Manne <nava.manne@xilinx.com>");
+MODULE_AUTHOR("Kalyani Akula <kalyani.akula@xilinx.com>");
--
1.8.3.1