[PATCH v1 1/4] crypto: aspeed: Add ACRY RSA driver

Neal Liu
2022-09-02T06:00:37Z

ACRY Engine is designed to accelerate the throughput of
ECDSA/RSA signature and verification.

This patch aims to add ACRY RSA engine driver for hardware
acceleration.

Signed-off-by: Neal Liu <neal_liu@aspeedtech.com>
---
drivers/crypto/aspeed/Kconfig | 11 +
drivers/crypto/aspeed/Makefile | 5 +-
drivers/crypto/aspeed/aspeed-acry.c | 848 ++++++++++++++++++++++++++++
3 files changed, 863 insertions(+), 1 deletion(-)
create mode 100644 drivers/crypto/aspeed/aspeed-acry.c

diff --git a/drivers/crypto/aspeed/Kconfig b/drivers/crypto/aspeed/Kconfig
index 001bf2e09a72..d0d88196ccc1 100644
--- a/drivers/crypto/aspeed/Kconfig
+++ b/drivers/crypto/aspeed/Kconfig
@@ -47,3 +47,14 @@ config CRYPTO_DEV_ASPEED_HACE_CRYPTO
crypto driver.
Supports AES/DES symmetric-key encryption and decryption
with ECB/CBC/CFB/OFB/CTR options.
+
+config CRYPTO_DEV_ASPEED_ACRY
+ bool "Enable Aspeed ACRY RSA Engine"
+ depends on CRYPTO_DEV_ASPEED
+ select CRYPTO_ENGINE
+ select CRYPTO_RSA
+ help
+ Select here to enable Aspeed ECC/RSA Engine (ACRY)
+ RSA driver.
+ Supports 256 bits to 4096 bits RSA encryption/decryption
+ and signature/verification.
diff --git a/drivers/crypto/aspeed/Makefile b/drivers/crypto/aspeed/Makefile
index 4cc1a7ad3652..8a2a8c905860 100644
--- a/drivers/crypto/aspeed/Makefile
+++ b/drivers/crypto/aspeed/Makefile
@@ -2,8 +2,11 @@ obj-$(CONFIG_CRYPTO_DEV_ASPEED_HACE_HASH) += aspeed-hace-hash.o
hace-hash-$(CONFIG_CRYPTO_DEV_ASPEED_HACE_HASH) := aspeed-hace-hash.o
obj-$(CONFIG_CRYPTO_DEV_ASPEED_HACE_CRYPTO) += aspeed-hace-crypto.o
hace-crypto-$(CONFIG_CRYPTO_DEV_ASPEED_HACE_CRYPTO) := aspeed-hace-crypto.o
+obj-$(CONFIG_CRYPTO_DEV_ASPEED_ACRY) += aspeed-acry.o
+hace-crypto-$(CONFIG_CRYPTO_DEV_ACRY) := aspeed-acry.o

obj-$(CONFIG_CRYPTO_DEV_ASPEED) += aspeed_crypto.o
aspeed_crypto-objs := aspeed-hace.o \
$(hace-hash-y) \
- $(hace-crypto-y)
+ $(hace-crypto-y) \
+ $(acry-y)
diff --git a/drivers/crypto/aspeed/aspeed-acry.c b/drivers/crypto/aspeed/aspeed-acry.c
new file mode 100644
index 000000000000..1d9a9b71afca
--- /dev/null
+++ b/drivers/crypto/aspeed/aspeed-acry.c
@@ -0,0 +1,848 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021 Aspeed Technology Inc.
+ */
+#include <crypto/akcipher.h>
+#include <crypto/algapi.h>
+#include <crypto/engine.h>
+#include <crypto/internal/akcipher.h>
+#include <crypto/internal/rsa.h>
+#include <crypto/scatterwalk.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/interrupt.h>
+#include <linux/count_zeros.h>
+#include <linux/err.h>
+#include <linux/dma-mapping.h>
+#include <linux/regmap.h>
+
+#ifdef CONFIG_CRYPTO_DEV_ASPEED_DEBUG
+#define ACRY_DBG(d, fmt, ...) \
+ dev_info((d)->dev, "%s() " fmt, __func__, ##__VA_ARGS__)
+#else
+#define ACRY_DBG(d, fmt, ...) \
+ dev_dbg((d)->dev, "%s() " fmt, __func__, ##__VA_ARGS__)
+#endif
+
+/*****************************
+ * *
+ * ACRY register definitions *
+ * *
+ * ***************************/
+#define ASPEED_ACRY_TRIGGER 0x000 /* ACRY Engine Control: trigger */
+#define ASPEED_ACRY_DMA_CMD 0x048 /* ACRY Engine Control: Command */
+#define ASPEED_ACRY_DMA_SRC_BASE 0x04C /* ACRY DRAM base address for DMA */
+#define ASPEED_ACRY_DMA_LEN 0x050 /* ACRY Data Length of DMA */
+#define ASPEED_ACRY_RSA_KEY_LEN 0x058 /* ACRY RSA Exp/Mod Key Length (Bits) */
+#define ASPEED_ACRY_INT_MASK 0x3F8 /* ACRY Interrupt Mask */
+#define ASPEED_ACRY_STATUS 0x3FC /* ACRY Interrupt Status */
+
+/* rsa trigger */
+#define ACRY_CMD_RSA_TRIGGER BIT(0)
+#define ACRY_CMD_DMA_RSA_TRIGGER BIT(1)
+
+/* rsa dma cmd */
+#define ACRY_CMD_DMA_SRAM_MODE_RSA (0x3 << 4)
+#define ACRY_CMD_DMEM_AHB BIT(8)
+#define ACRY_CMD_DMA_SRAM_AHB_ENGINE 0
+
+/* rsa key len */
+#define RSA_E_BITS_LEN(x) (x << 16)
+#define RSA_M_BITS_LEN(x) (x)
+
+/* acry isr */
+#define ACRY_RSA_ISR BIT(1)
+
+#define ASPEED_ACRY_BUFF_SIZE 0x1800 /* DMA buffer size */
+#define ASPEED_ACRY_SRAM_MAX_LEN 2048 /* ACRY SRAM maximum length (Bytes) */
+#define ASPEED_ACRY_RSA_MAX_KEY_LEN 512 /* ACRY RSA maximum key length (Bytes) */
+
+#define CRYPTO_FLAGS_BUSY BIT(1)
+#define BYTES_PER_DWORD 4
+
+/*****************************
+ * *
+ * AHBC register definitions *
+ * *
+ * ***************************/
+#define AHBC_REGION_PROT 0x240
+#define REGION_ACRYM BIT(23)
+
+#define ast_acry_write(acry, val, offset) \
+ writel((val), (acry)->regs + (offset))
+
+#define ast_acry_read(acry, offset) \
+ readl((acry)->regs + (offset))
+
+struct aspeed_acry_dev;
+
+typedef int (*aspeed_acry_fn_t)(struct aspeed_acry_dev *);
+
+struct aspeed_acry_dev {
+ void __iomem *regs;
+ struct device *dev;
+ int irq;
+ struct clk *clk;
+ struct regmap *ahbc;
+
+ struct akcipher_request *req;
+ struct tasklet_struct done_task;
+ aspeed_acry_fn_t resume;
+ unsigned long flags;
+
+ /* ACRY output SRAM buffer */
+ void __iomem *acry_sram;
+
+ /* ACRY input DMA buffer */
+ void *buf_addr;
+ dma_addr_t buf_dma_addr;
+
+ struct crypto_engine *crypt_engine_rsa;
+
+ /* ACRY SRAM memory mapped */
+ int exp_dw_mapping[ASPEED_ACRY_RSA_MAX_KEY_LEN];
+ int mod_dw_mapping[ASPEED_ACRY_RSA_MAX_KEY_LEN];
+ int data_byte_mapping[ASPEED_ACRY_SRAM_MAX_LEN];
+};
+
+struct aspeed_acry_ctx {
+ struct crypto_engine_ctx enginectx;
+ struct aspeed_acry_dev *acry_dev;
+
+ struct rsa_key key;
+ int enc;
+ u8 *n;
+ u8 *e;
+ u8 *d;
+ size_t n_sz;
+ size_t e_sz;
+ size_t d_sz;
+
+ aspeed_acry_fn_t trigger;
+
+ struct crypto_akcipher *fallback_tfm;
+};
+
+struct aspeed_acry_alg {
+ struct aspeed_acry_dev *acry_dev;
+ struct akcipher_alg akcipher;
+};
+
+enum aspeed_rsa_key_mode {
+ ASPEED_RSA_EXP_MODE = 0,
+ ASPEED_RSA_MOD_MODE,
+ ASPEED_RSA_DATA_MODE,
+};
+
+static inline struct akcipher_request *akcipher_request_cast(
+ struct crypto_async_request *req)
+{
+ return container_of(req, struct akcipher_request, base);
+}
+
+static int aspeed_acry_do_fallback(struct akcipher_request *req)
+{
+ struct crypto_akcipher *cipher = crypto_akcipher_reqtfm(req);
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(cipher);
+ int err;
+
+ akcipher_request_set_tfm(req, ctx->fallback_tfm);
+
+ if (ctx->enc)
+ err = crypto_akcipher_encrypt(req);
+ else
+ err = crypto_akcipher_decrypt(req);
+
+ akcipher_request_set_tfm(req, cipher);
+
+ return err;
+}
+
+static bool aspeed_acry_need_fallback(struct akcipher_request *req)
+{
+ struct crypto_akcipher *cipher = crypto_akcipher_reqtfm(req);
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(cipher);
+
+ if (ctx->key.n_sz > ASPEED_ACRY_RSA_MAX_KEY_LEN)
+ return true;
+
+ return false;
+}
+
+static int aspeed_acry_handle_queue(struct aspeed_acry_dev *acry_dev,
+ struct akcipher_request *req)
+{
+ if (aspeed_acry_need_fallback(req)) {
+ ACRY_DBG(acry_dev, "SW fallback\n");
+ return aspeed_acry_do_fallback(req);
+ }
+
+ return crypto_transfer_akcipher_request_to_engine(
+ acry_dev->crypt_engine_rsa, req);
+}
+
+static int aspeed_acry_do_request(struct crypto_engine *engine, void *areq)
+{
+ struct akcipher_request *req = akcipher_request_cast(areq);
+ struct crypto_akcipher *cipher = crypto_akcipher_reqtfm(req);
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(cipher);
+ struct aspeed_acry_dev *acry_dev = ctx->acry_dev;
+ int rc;
+
+ acry_dev->req = req;
+ acry_dev->flags |= CRYPTO_FLAGS_BUSY;
+ rc = ctx->trigger(acry_dev);
+
+ if (rc != -EINPROGRESS)
+ return -EIO;
+
+ return 0;
+}
+
+static int aspeed_acry_complete(struct aspeed_acry_dev *acry_dev, int err)
+{
+ struct akcipher_request *req = acry_dev->req;
+
+ acry_dev->flags &= ~CRYPTO_FLAGS_BUSY;
+
+ crypto_finalize_akcipher_request(acry_dev->crypt_engine_rsa, req, err);
+
+ return err;
+}
+
+/*
+ * Copy Data to DMA buffer for engine used.
+ */
+static void aspeed_acry_rsa_sg_copy_to_buffer(struct aspeed_acry_dev *acry_dev,
+ u8 *buf, struct scatterlist *src,
+ size_t nbytes)
+{
+ static u8 dram_buffer[ASPEED_ACRY_SRAM_MAX_LEN];
+ int i = 0, j;
+ int data_idx;
+
+ ACRY_DBG(acry_dev, "\n");
+
+ scatterwalk_map_and_copy(dram_buffer, src, 0, nbytes, 0);
+
+ for (j = nbytes - 1; j >= 0; j--) {
+ data_idx = acry_dev->data_byte_mapping[i];
+ buf[data_idx] = dram_buffer[j];
+ i++;
+ }
+
+ for (; i < ASPEED_ACRY_SRAM_MAX_LEN; i++) {
+ data_idx = acry_dev->data_byte_mapping[i];
+ buf[data_idx] = 0;
+ }
+}
+
+/*
+ * Copy Exp/Mod to DMA buffer for engine used.
+ *
+ * Params:
+ * - mode 0 : Exponential
+ * - mode 1 : Modulus
+ *
+ * Example:
+ * - DRAM memory layout:
+ * D[0], D[4], D[8], D[12]
+ * - ACRY SRAM memory layout should reverse the order of source data:
+ * D[12], D[8], D[4], D[0]
+ */
+static int aspeed_acry_rsa_ctx_copy(struct aspeed_acry_dev *acry_dev, void *buf,
+ const void *xbuf, size_t nbytes,
+ enum aspeed_rsa_key_mode mode)
+{
+ const uint8_t *src = xbuf;
+ u32 *dw_buf = (u32 *)buf;
+ int nbits, ndw;
+ int i, j, idx;
+ u32 data;
+
+ ACRY_DBG(acry_dev, "nbytes:0x%x, mode:%d\n", nbytes, mode);
+
+ if (nbytes > ASPEED_ACRY_RSA_MAX_KEY_LEN)
+ return -ENOMEM;
+
+ /* Remove the leading zeros */
+ while (nbytes > 0 && src[0] == 0) {
+ src++;
+ nbytes--;
+ }
+
+ nbits = nbytes * 8;
+ if (nbytes > 0)
+ nbits -= count_leading_zeros(src[0]) - (BITS_PER_LONG - 8);
+
+ /* double-world alignment */
+ ndw = DIV_ROUND_UP(nbytes, BYTES_PER_DWORD);
+
+ if (nbytes > 0) {
+ i = BYTES_PER_DWORD - nbytes % BYTES_PER_DWORD;
+ i %= BYTES_PER_DWORD;
+
+ for (j = ndw; j > 0; j--) {
+ for (; i < BYTES_PER_DWORD; i++) {
+ data <<= 8;
+ data |= *src++;
+ }
+
+ i = 0;
+
+ if (mode == ASPEED_RSA_EXP_MODE)
+ idx = acry_dev->exp_dw_mapping[j - 1];
+ else if (mode == ASPEED_RSA_MOD_MODE)
+ idx = acry_dev->mod_dw_mapping[j - 1];
+
+ dw_buf[idx] = cpu_to_le32(data);
+ }
+ }
+
+ return nbits;
+}
+
+static int aspeed_acry_rsa_transfer(struct aspeed_acry_dev *acry_dev)
+{
+ struct akcipher_request *req = acry_dev->req;
+ u8 *sram_buffer = (u8 *)acry_dev->acry_sram;
+ struct scatterlist *out_sg = req->dst;
+ static u8 dram_buffer[ASPEED_ACRY_SRAM_MAX_LEN];
+ int leading_zero = 1;
+ int result_nbytes;
+ int i = 0, j;
+ int data_idx;
+
+ /* Set Data Memory to AHB(CPU) Access Mode */
+ ast_acry_write(acry_dev, ACRY_CMD_DMEM_AHB, ASPEED_ACRY_DMA_CMD);
+
+ /* Disable ACRY SRAM protection */
+ regmap_update_bits(acry_dev->ahbc, AHBC_REGION_PROT,
+ REGION_ACRYM, 0);
+
+ result_nbytes = ASPEED_ACRY_SRAM_MAX_LEN;
+
+ for (j = ASPEED_ACRY_SRAM_MAX_LEN - 1; j >= 0; j--) {
+ data_idx = acry_dev->data_byte_mapping[j];
+ if (sram_buffer[data_idx] == 0 && leading_zero) {
+ result_nbytes--;
+ } else {
+ leading_zero = 0;
+ dram_buffer[i] = sram_buffer[data_idx];
+ i++;
+ }
+ }
+
+ ACRY_DBG(acry_dev, "result_nbytes:%d, req->dst_len:%d\n",
+ result_nbytes, req->dst_len);
+
+ if (result_nbytes <= req->dst_len) {
+ scatterwalk_map_and_copy(dram_buffer, out_sg, 0, result_nbytes,
+ 1);
+ req->dst_len = result_nbytes;
+
+ } else {
+ dev_err(acry_dev->dev, "RSA engine error!\n");
+ }
+
+ memzero_explicit(acry_dev->buf_addr, ASPEED_ACRY_BUFF_SIZE);
+
+ return aspeed_acry_complete(acry_dev, 0);
+}
+
+static int aspeed_acry_rsa_trigger(struct aspeed_acry_dev *acry_dev)
+{
+ struct akcipher_request *req = acry_dev->req;
+ struct crypto_akcipher *cipher = crypto_akcipher_reqtfm(req);
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(cipher);
+ int ne, nm;
+
+ if (!ctx->n || !ctx->n_sz) {
+ dev_err(acry_dev->dev, "%s: key n is not set\n", __func__);
+ return -EINVAL;
+ }
+
+ memzero_explicit(acry_dev->buf_addr, ASPEED_ACRY_BUFF_SIZE);
+
+ /* Copy source data to DMA buffer */
+ aspeed_acry_rsa_sg_copy_to_buffer(acry_dev, acry_dev->buf_addr,
+ req->src, req->src_len);
+
+ nm = aspeed_acry_rsa_ctx_copy(acry_dev, acry_dev->buf_addr, ctx->n,
+ ctx->n_sz, ASPEED_RSA_MOD_MODE);
+ if (ctx->enc) {
+ if (!ctx->e || !ctx->e_sz) {
+ dev_err(acry_dev->dev, "%s: key e is not set\n",
+ __func__);
+ return -EINVAL;
+ }
+ /* Copy key e to DMA buffer */
+ ne = aspeed_acry_rsa_ctx_copy(acry_dev, acry_dev->buf_addr,
+ ctx->e, ctx->e_sz,
+ ASPEED_RSA_EXP_MODE);
+ } else {
+ if (!ctx->d || !ctx->d_sz) {
+ dev_err(acry_dev->dev, "%s: key d is not set\n",
+ __func__);
+ return -EINVAL;
+ }
+ /* Copy key d to DMA buffer */
+ ne = aspeed_acry_rsa_ctx_copy(acry_dev, acry_dev->buf_addr,
+ ctx->key.d, ctx->key.d_sz,
+ ASPEED_RSA_EXP_MODE);
+ }
+
+ ast_acry_write(acry_dev, acry_dev->buf_dma_addr,
+ ASPEED_ACRY_DMA_SRC_BASE);
+ ast_acry_write(acry_dev, (ne << 16) + nm,
+ ASPEED_ACRY_RSA_KEY_LEN);
+ ast_acry_write(acry_dev, ASPEED_ACRY_BUFF_SIZE,
+ ASPEED_ACRY_DMA_LEN);
+
+ acry_dev->resume = aspeed_acry_rsa_transfer;
+
+ /* Enable ACRY SRAM protection */
+ regmap_update_bits(acry_dev->ahbc, AHBC_REGION_PROT,
+ REGION_ACRYM, REGION_ACRYM);
+
+ ast_acry_write(acry_dev, ACRY_RSA_ISR, ASPEED_ACRY_INT_MASK);
+ ast_acry_write(acry_dev, ACRY_CMD_DMA_SRAM_MODE_RSA |
+ ACRY_CMD_DMA_SRAM_AHB_ENGINE, ASPEED_ACRY_DMA_CMD);
+
+ /* Trigger RSA engines */
+ ast_acry_write(acry_dev, ACRY_CMD_RSA_TRIGGER |
+ ACRY_CMD_DMA_RSA_TRIGGER, ASPEED_ACRY_TRIGGER);
+
+ return -EINPROGRESS;
+}
+
+static int aspeed_acry_rsa_enc(struct akcipher_request *req)
+{
+ struct crypto_akcipher *cipher = crypto_akcipher_reqtfm(req);
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(cipher);
+ struct aspeed_acry_dev *acry_dev = ctx->acry_dev;
+
+ ctx->trigger = aspeed_acry_rsa_trigger;
+ ctx->enc = 1;
+
+ return aspeed_acry_handle_queue(acry_dev, req);
+}
+
+static int aspeed_acry_rsa_dec(struct akcipher_request *req)
+{
+ struct crypto_akcipher *cipher = crypto_akcipher_reqtfm(req);
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(cipher);
+ struct aspeed_acry_dev *acry_dev = ctx->acry_dev;
+
+ ctx->trigger = aspeed_acry_rsa_trigger;
+ ctx->enc = 0;
+
+ return aspeed_acry_handle_queue(acry_dev, req);
+}
+
+static u8 *aspeed_rsa_key_copy(u8 *src, size_t len)
+{
+ u8 *dst;
+
+ dst = kmemdup(src, len, GFP_DMA | GFP_KERNEL);
+ return dst;
+}
+
+static int aspeed_rsa_set_n(struct aspeed_acry_ctx *ctx, u8 *value,
+ size_t len)
+{
+ ctx->n_sz = len;
+ ctx->n = aspeed_rsa_key_copy(value, len);
+ if (!ctx->n)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int aspeed_rsa_set_e(struct aspeed_acry_ctx *ctx, u8 *value,
+ size_t len)
+{
+ ctx->e_sz = len;
+ ctx->e = aspeed_rsa_key_copy(value, len);
+ if (!ctx->e)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int aspeed_rsa_set_d(struct aspeed_acry_ctx *ctx, u8 *value,
+ size_t len)
+{
+ ctx->d_sz = len;
+ ctx->d = aspeed_rsa_key_copy(value, len);
+ if (!ctx->d)
+ return -EINVAL;
+
+ return 0;
+}
+
+static void aspeed_rsa_key_free(struct aspeed_acry_ctx *ctx)
+{
+ kfree_sensitive(ctx->n);
+ kfree_sensitive(ctx->e);
+ kfree_sensitive(ctx->d);
+ ctx->n_sz = 0;
+ ctx->e_sz = 0;
+ ctx->d_sz = 0;
+}
+
+static int aspeed_acry_rsa_setkey(struct crypto_akcipher *tfm, const void *key,
+ unsigned int keylen, int priv)
+{
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct aspeed_acry_dev *acry_dev = ctx->acry_dev;
+ int ret;
+
+ if (priv)
+ ret = rsa_parse_priv_key(&ctx->key, key, keylen);
+ else
+ ret = rsa_parse_pub_key(&ctx->key, key, keylen);
+
+ if (ret) {
+ dev_err(acry_dev->dev, "rsa parse key failed, ret:0x%x\n",
+ ret);
+ return ret;
+ }
+
+ /* Aspeed engine supports up to 4096 bits,
+ * Use software fallback instead.
+ */
+ if (ctx->key.n_sz > ASPEED_ACRY_RSA_MAX_KEY_LEN)
+ return 0;
+
+ ret = aspeed_rsa_set_n(ctx, (u8 *)ctx->key.n, ctx->key.n_sz);
+ if (ret)
+ goto err;
+
+ ret = aspeed_rsa_set_e(ctx, (u8 *)ctx->key.e, ctx->key.e_sz);
+ if (ret)
+ goto err;
+
+ if (priv) {
+ ret = aspeed_rsa_set_d(ctx, (u8 *)ctx->key.d, ctx->key.d_sz);
+ if (ret)
+ goto err;
+ }
+
+ return 0;
+
+err:
+ dev_err(acry_dev->dev, "rsa set key failed\n");
+ aspeed_rsa_key_free(ctx);
+
+ return ret;
+}
+
+static int aspeed_acry_rsa_set_pub_key(struct crypto_akcipher *tfm,
+ const void *key,
+ unsigned int keylen)
+{
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(tfm);
+ int ret;
+
+ ret = crypto_akcipher_set_pub_key(ctx->fallback_tfm, key, keylen);
+ if (ret)
+ return ret;
+
+ return aspeed_acry_rsa_setkey(tfm, key, keylen, 0);
+}
+
+static int aspeed_acry_rsa_set_priv_key(struct crypto_akcipher *tfm,
+ const void *key,
+ unsigned int keylen)
+{
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(tfm);
+ int ret;
+
+ ret = crypto_akcipher_set_priv_key(ctx->fallback_tfm, key, keylen);
+ if (ret)
+ return ret;
+
+ return aspeed_acry_rsa_setkey(tfm, key, keylen, 1);
+}
+
+static unsigned int aspeed_acry_rsa_max_size(struct crypto_akcipher *tfm)
+{
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(tfm);
+
+ if (ctx->key.n_sz > ASPEED_ACRY_RSA_MAX_KEY_LEN)
+ return crypto_akcipher_maxsize(ctx->fallback_tfm);
+
+ return ctx->n_sz;
+}
+
+static int aspeed_acry_rsa_init_tfm(struct crypto_akcipher *tfm)
+{
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(tfm);
+ struct akcipher_alg *alg = crypto_akcipher_alg(tfm);
+ const char *name = crypto_tfm_alg_name(&tfm->base);
+ struct aspeed_acry_alg *acry_alg;
+
+ acry_alg = container_of(alg, struct aspeed_acry_alg, akcipher);
+
+ ctx->acry_dev = acry_alg->acry_dev;
+
+ ctx->fallback_tfm = crypto_alloc_akcipher(name, 0, CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_NEED_FALLBACK);
+ if (IS_ERR(ctx->fallback_tfm)) {
+ dev_err(ctx->acry_dev->dev, "ERROR: Cannot allocate fallback for %s %ld\n",
+ name, PTR_ERR(ctx->fallback_tfm));
+ return PTR_ERR(ctx->fallback_tfm);
+ }
+
+ ctx->enginectx.op.do_one_request = aspeed_acry_do_request;
+ ctx->enginectx.op.prepare_request = NULL;
+ ctx->enginectx.op.unprepare_request = NULL;
+
+ return 0;
+}
+
+static void aspeed_acry_rsa_exit_tfm(struct crypto_akcipher *tfm)
+{
+ struct aspeed_acry_ctx *ctx = akcipher_tfm_ctx(tfm);
+
+ crypto_free_akcipher(ctx->fallback_tfm);
+}
+
+struct aspeed_acry_alg aspeed_acry_akcipher_algs[] = {
+ {
+ .akcipher = {
+ .encrypt = aspeed_acry_rsa_enc,
+ .decrypt = aspeed_acry_rsa_dec,
+ .sign = aspeed_acry_rsa_dec,
+ .verify = aspeed_acry_rsa_enc,
+ .set_pub_key = aspeed_acry_rsa_set_pub_key,
+ .set_priv_key = aspeed_acry_rsa_set_priv_key,
+ .max_size = aspeed_acry_rsa_max_size,
+ .init = aspeed_acry_rsa_init_tfm,
+ .exit = aspeed_acry_rsa_exit_tfm,
+ .base = {
+ .cra_name = "rsa",
+ .cra_driver_name = "aspeed-rsa",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_AKCIPHER |
+ CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_KERN_DRIVER_ONLY |
+ CRYPTO_ALG_NEED_FALLBACK,
+ .cra_module = THIS_MODULE,
+ .cra_ctxsize = sizeof(struct aspeed_acry_ctx),
+ },
+ },
+ },
+};
+
+static void aspeed_acry_register(struct aspeed_acry_dev *acry_dev)
+{
+ int i, rc;
+
+ for (i = 0; i < ARRAY_SIZE(aspeed_acry_akcipher_algs); i++) {
+ aspeed_acry_akcipher_algs[i].acry_dev = acry_dev;
+ rc = crypto_register_akcipher(&aspeed_acry_akcipher_algs[i].akcipher);
+ if (rc) {
+ ACRY_DBG(acry_dev, "Failed to register %s\n",
+ aspeed_acry_akcipher_algs[i].akcipher.base.cra_name);
+ }
+ }
+}
+
+static void aspeed_acry_unregister(struct aspeed_acry_dev *acry_dev)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(aspeed_acry_akcipher_algs); i++)
+ crypto_unregister_akcipher(&aspeed_acry_akcipher_algs[i].akcipher);
+}
+
+/* ACRY interrupt service routine. */
+static irqreturn_t aspeed_acry_irq(int irq, void *dev)
+{
+ struct aspeed_acry_dev *acry_dev = (struct aspeed_acry_dev *)dev;
+ u32 sts;
+
+ sts = ast_acry_read(acry_dev, ASPEED_ACRY_STATUS);
+ ast_acry_write(acry_dev, sts, ASPEED_ACRY_STATUS);
+
+ ACRY_DBG(acry_dev, "irq sts:0x%x\n", sts);
+
+ if (sts & ACRY_RSA_ISR) {
+ /* Stop RSA engine */
+ ast_acry_write(acry_dev, 0, ASPEED_ACRY_TRIGGER);
+
+ if (acry_dev->flags & CRYPTO_FLAGS_BUSY)
+ tasklet_schedule(&acry_dev->done_task);
+ else
+ dev_err(acry_dev->dev, "RSA no active requests.\n");
+ }
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * ACRY SRAM has its own memory layout.
+ * Set the DRAM to SRAM indexing for future used.
+ */
+static void aspeed_acry_sram_mapping(struct aspeed_acry_dev *acry_dev)
+{
+ int i, j = 0;
+
+ for (i = 0; i < (ASPEED_ACRY_SRAM_MAX_LEN / BYTES_PER_DWORD); i++) {
+ acry_dev->exp_dw_mapping[i] = j;
+ acry_dev->mod_dw_mapping[i] = j + 4;
+ acry_dev->data_byte_mapping[(i * 4)] = (j + 8) * 4;
+ acry_dev->data_byte_mapping[(i * 4) + 1] = (j + 8) * 4 + 1;
+ acry_dev->data_byte_mapping[(i * 4) + 2] = (j + 8) * 4 + 2;
+ acry_dev->data_byte_mapping[(i * 4) + 3] = (j + 8) * 4 + 3;
+ j++;
+ j = j % 4 ? j : j + 8;
+ }
+}
+
+static void aspeed_acry_done_task(unsigned long data)
+{
+ struct aspeed_acry_dev *acry_dev = (struct aspeed_acry_dev *)data;
+
+ (void)acry_dev->resume(acry_dev);
+}
+
+static const struct of_device_id aspeed_acry_of_matches[] = {
+ { .compatible = "aspeed,ast2600-acry", },
+ {},
+};
+
+static int aspeed_acry_probe(struct platform_device *pdev)
+{
+ struct aspeed_acry_dev *acry_dev;
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ int rc;
+
+ acry_dev = devm_kzalloc(dev, sizeof(struct aspeed_acry_dev),
+ GFP_KERNEL);
+ if (!acry_dev)
+ return -ENOMEM;
+
+ acry_dev->dev = dev;
+
+ platform_set_drvdata(pdev, acry_dev);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ acry_dev->regs = devm_ioremap_resource(dev, res);
+ if (IS_ERR(acry_dev->regs))
+ return PTR_ERR(acry_dev->regs);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ acry_dev->acry_sram = devm_ioremap_resource(dev, res);
+ if (IS_ERR(acry_dev->acry_sram))
+ return PTR_ERR(acry_dev->acry_sram);
+
+ /* Get irq number and register it */
+ acry_dev->irq = platform_get_irq(pdev, 0);
+ if (!acry_dev->irq) {
+ dev_err(dev, "Failed to get interrupt\n");
+ return -ENXIO;
+ }
+
+ rc = devm_request_irq(dev, acry_dev->irq, aspeed_acry_irq, 0,
+ dev_name(dev), acry_dev);
+ if (rc) {
+ dev_err(dev, "Failed to request irq.\n");
+ return rc;
+ }
+
+ acry_dev->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(acry_dev->clk)) {
+ dev_err(dev, "Failed to get clk\n");
+ return -ENODEV;
+ }
+
+ acry_dev->ahbc = syscon_regmap_lookup_by_phandle(dev->of_node,
+ "aspeed,ahbc");
+ if (IS_ERR(acry_dev->ahbc)) {
+ dev_err(dev, "Failed to get AHBC regmap\n");
+ return -ENODEV;
+ }
+
+ rc = clk_prepare_enable(acry_dev->clk);
+ if (rc) {
+ dev_err(dev, "Failed to enable clock 0x%x\n", rc);
+ return rc;
+ }
+
+ /* Initialize crypto hardware engine structure for RSA */
+ acry_dev->crypt_engine_rsa = crypto_engine_alloc_init(dev, true);
+ if (!acry_dev->crypt_engine_rsa) {
+ rc = -ENOMEM;
+ goto clk_exit;
+ }
+
+ rc = crypto_engine_start(acry_dev->crypt_engine_rsa);
+ if (rc)
+ goto err_engine_rsa_start;
+
+ tasklet_init(&acry_dev->done_task, aspeed_acry_done_task,
+ (unsigned long)acry_dev);
+
+ /* Set Data Memory to AHB(CPU) Access Mode */
+ ast_acry_write(acry_dev, ACRY_CMD_DMEM_AHB, ASPEED_ACRY_DMA_CMD);
+
+ /* Initialize ACRY SRAM index */
+ aspeed_acry_sram_mapping(acry_dev);
+
+ acry_dev->buf_addr = dmam_alloc_coherent(dev, ASPEED_ACRY_BUFF_SIZE,
+ &acry_dev->buf_dma_addr,
+ GFP_KERNEL);
+ memzero_explicit(acry_dev->buf_addr, ASPEED_ACRY_BUFF_SIZE);
+
+ aspeed_acry_register(acry_dev);
+
+ dev_info(dev, "Aspeed ACRY Accelerator successfully registered\n");
+
+ return 0;
+
+err_engine_rsa_start:
+ crypto_engine_exit(acry_dev->crypt_engine_rsa);
+clk_exit:
+ clk_disable_unprepare(acry_dev->clk);
+
+ return rc;
+}
+
+static int aspeed_acry_remove(struct platform_device *pdev)
+{
+ struct aspeed_acry_dev *acry_dev = platform_get_drvdata(pdev);
+
+ aspeed_acry_unregister(acry_dev);
+ crypto_engine_exit(acry_dev->crypt_engine_rsa);
+ tasklet_kill(&acry_dev->done_task);
+ clk_disable_unprepare(acry_dev->clk);
+
+ return 0;
+}
+
+MODULE_DEVICE_TABLE(of, aspeed_acry_of_matches);
+
+static struct platform_driver aspeed_acry_driver = {
+ .probe = aspeed_acry_probe,
+ .remove = aspeed_acry_remove,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = aspeed_acry_of_matches,
+ },
+};
+
+module_platform_driver(aspeed_acry_driver);
+
+MODULE_AUTHOR("Neal Liu <neal_liu@aspeedtech.com>");
+MODULE_DESCRIPTION("ASPEED ACRY driver for hardware RSA Engine");
+MODULE_LICENSE("GPL");
--
2.25.1