drivers: crypto: add it51xxx sha256 driver

Yunshao-Chiang · kartben · commit 8f8b223ff2c3 · 2025-05-16T19:07:37.000+02:00
Implement a crypto sha256 driver for it51xxx series.

Signed-off-by: Yunshao Chiang &lt;Yunshao.Chiang@ite.com.tw&gt;
diff --git a/boards/ite/it515xx_evb/it515xx_evb.dts b/boards/ite/it515xx_evb/it515xx_evb.dts
@@ -149,3 +149,7 @@
 	pinctrl-0 = <&tach0a_gpd6_default>;
 	pinctrl-names = "default";
 };
+
+&sha256 {
+	status = "okay";
+};
diff --git a/drivers/crypto/CMakeLists.txt b/drivers/crypto/CMakeLists.txt
@@ -10,6 +10,7 @@ zephyr_library_sources_ifdef(CONFIG_CRYPTO_NRF_ECB		crypto_nrf_ecb.c)
 zephyr_library_sources_ifdef(CONFIG_CRYPTO_INTEL_SHA		crypto_intel_sha.c)
 zephyr_library_sources_ifdef(CONFIG_CRYPTO_NPCX_SHA		crypto_npcx_sha.c)
 zephyr_library_sources_ifdef(CONFIG_CRYPTO_MCHP_XEC_SYMCR	crypto_mchp_xec_symcr.c)
+zephyr_library_sources_ifdef(CONFIG_CRYPTO_IT51XXX_SHA		crypto_it51xxx_sha.c)
 zephyr_library_sources_ifdef(CONFIG_CRYPTO_IT8XXX2_SHA		crypto_it8xxx2_sha.c)
 zephyr_library_sources_ifdef(CONFIG_CRYPTO_IT8XXX2_SHA_V2	crypto_it8xxx2_sha_v2.c)
 zephyr_library_sources_ifdef(CONFIG_CRYPTO_MCUX_DCP		crypto_mcux_dcp.c)
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
@@ -80,6 +80,7 @@ source "drivers/crypto/Kconfig.nrf_ecb"
 source "drivers/crypto/Kconfig.intel"
 source "drivers/crypto/Kconfig.npcx"
 source "drivers/crypto/Kconfig.xec"
+source "drivers/crypto/Kconfig.it51xxx"
 source "drivers/crypto/Kconfig.it8xxx2"
 source "drivers/crypto/Kconfig.mcux_dcp"
 source "drivers/crypto/Kconfig.si32"
diff --git a/drivers/crypto/Kconfig.it51xxx b/drivers/crypto/Kconfig.it51xxx
@@ -0,0 +1,11 @@
+# Copyright (c) 2025 ITE Corporation.
+# SPDX-License-Identifier: Apache-2.0
+
+config CRYPTO_IT51XXX_SHA
+	bool "ITE IT51XXX SHA driver"
+	default y
+	depends on DT_HAS_ITE_IT51XXX_SHA_ENABLED
+	select SOC_IT51XXX_SHA256_HW_ACCELERATE
+	help
+	  The IT51XXX hardware supports SHA-256 calculation, which is faster than
+	  the firmware implementation.
diff --git a/drivers/crypto/crypto_it51xxx_sha.c b/drivers/crypto/crypto_it51xxx_sha.c
@@ -0,0 +1,276 @@
+/*
+ * Copyright (c) 2025 ITE Corporation.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT ite_it51xxx_sha
+
+#include <errno.h>
+#include <it51xxx/chip_chipregs.h>
+#include <zephyr/crypto/crypto.h>
+#include <zephyr/kernel.h>
+#include <zephyr/sys/byteorder.h>
+
+#include <zephyr/logging/log.h>
+LOG_MODULE_REGISTER(crypto_it51xxx_sha, CONFIG_CRYPTO_LOG_LEVEL);
+
+#define IT51XXX_SHA_REGS_BASE DT_REG_ADDR(DT_NODELABEL(sha256))
+
+/* 0x00: SHA Control Register (SHACR) */
+#define IT51XXX_SHACR           (IT51XXX_SHA_REGS_BASE + 0x00)
+#define IT51XXX_SHAWB           BIT(2)
+#define IT51XXX_SHAINI          BIT(1)
+#define IT51XXX_SHAEXE          BIT(0)
+/* 0x01: SHA Status Register (SHASR)*/
+#define IT51XXX_SHASR           (IT51XXX_SHA_REGS_BASE + 0x01)
+#define IT51XXX_SHAIE           BIT(3)
+#define IT51XXX_SHAIS           BIT(2)
+#define IT51XXX_SHABUSY         BIT(0)
+/* 0x02: SHA Execution Counter Register (SHAECR) */
+#define IT51XXX_SHAECR          (IT51XXX_SHA_REGS_BASE + 0x02)
+#define IT51XXX_SHAEXEC_64_BYTE 0x00
+#define IT51XXX_SHAEXEC_1K_BYTE 0x0F
+/* 0x03: SHA DLM Base Address 0 Register (SHADBA0R) */
+#define IT51XXX_SHADBA0R        (IT51XXX_SHA_REGS_BASE + 0x03)
+/* 0x04: SHA DLM Base Address 1 Register (SHADBA1R) */
+#define IT51XXX_SHADBA1R        (IT51XXX_SHA_REGS_BASE + 0x04)
+/* 0x05: SHA Setting Register (SHASETR) */
+#define IT51XXX_SHASETR         (IT51XXX_SHA_REGS_BASE + 0x05)
+#define IT51XXX_SHA256          0x00
+/* 0x06: SHA DLM Base Address 2 Register (SHADBA2R) */
+#define IT51XXX_SHADBA2R        (IT51XXX_SHA_REGS_BASE + 0x06)
+
+#define SHA_SHA256_HASH_LEN        32
+#define SHA_SHA256_BLOCK_LEN       64
+#define SHA_SHA256_HASH_LEN_WORDS  (SHA_SHA256_HASH_LEN / sizeof(uint32_t))
+#define SHA_SHA256_BLOCK_LEN_WORDS (SHA_SHA256_BLOCK_LEN / sizeof(uint32_t))
+
+/*
+ * If the input message is more than 1K bytes, taking 10K bytes for example,
+ * it should run 10 times SHA hardwired loading and execution, and process 1K bytes each time.
+ */
+#define SHA_HW_MAX_INPUT_LEN       1024
+#define SHA_HW_MAX_INPUT_LEN_WORDS (SHA_HW_MAX_INPUT_LEN / sizeof(uint32_t))
+
+/*
+ * This struct is used by the hardware and must be stored in RAM first 4k-byte
+ * and aligned on a 256-byte boundary.
+ */
+struct chip_sha256_ctx {
+	union {
+		/* SHA data buffer */
+		uint32_t w_sha[SHA_HW_MAX_INPUT_LEN_WORDS];
+		uint8_t w_input[SHA_HW_MAX_INPUT_LEN];
+	};
+	/* H[0] ~ H[7] */
+	uint32_t h[SHA_SHA256_HASH_LEN_WORDS];
+	uint32_t sha_init;
+	uint32_t w_input_index;
+	uint32_t total_len;
+} __aligned(256);
+
+Z_GENERIC_SECTION(.__sha256_ram_block) struct chip_sha256_ctx chip_ctx;
+
+static void it51xxx_sha256_init(bool init_k)
+{
+	chip_ctx.sha_init = init_k;
+	chip_ctx.total_len = 0;
+	chip_ctx.w_input_index = 0;
+
+	/* Set DLM address for input data */
+	sys_write8(((uint32_t)&chip_ctx) & 0xC0, IT51XXX_SHADBA0R);
+	sys_write8(((uint32_t)&chip_ctx) >> 8, IT51XXX_SHADBA1R);
+	sys_write8(((uint32_t)&chip_ctx) >> 16, IT51XXX_SHADBA2R);
+}
+
+static void it51xxx_sha256_module_calculation(void)
+{
+	uint32_t key;
+
+	/*
+	 * Global interrupt is disabled because the CPU cannot access memory
+	 * via the DLM (Data Local Memory) bus while HW module is computing
+	 * hash.
+	 */
+	key = irq_lock();
+
+	if (chip_ctx.sha_init) {
+		chip_ctx.sha_init = 0;
+		sys_write8(IT51XXX_SHAINI | IT51XXX_SHAEXE, IT51XXX_SHACR);
+	} else {
+		sys_write8(IT51XXX_SHAEXE, IT51XXX_SHACR);
+	}
+
+	while (sys_read8(IT51XXX_SHASR) & IT51XXX_SHABUSY) {
+	};
+	sys_write8(IT51XXX_SHAIS, IT51XXX_SHASR);
+
+	irq_unlock(key);
+
+	chip_ctx.w_input_index = 0;
+}
+
+static int it51xxx_hash_handler(struct hash_ctx *ctx, struct hash_pkt *pkt, bool finish)
+{
+	uint32_t i;
+	uint32_t in_buf_idx = 0;
+	uint32_t key;
+	uint32_t rem_len = pkt->in_len;
+
+	/* data length >= 1KiB */
+	while (rem_len >= SHA_HW_MAX_INPUT_LEN) {
+		rem_len = rem_len - SHA_HW_MAX_INPUT_LEN;
+
+		for (i = 0; i < SHA_HW_MAX_INPUT_LEN; i++) {
+			chip_ctx.w_input[chip_ctx.w_input_index++] = pkt->in_buf[in_buf_idx++];
+		}
+
+		/* HW automatically load 1KB data from DLM */
+		sys_write8(IT51XXX_SHAEXEC_1K_BYTE, IT51XXX_SHAECR);
+		while (sys_read8(IT51XXX_SHASR) & IT51XXX_SHABUSY) {
+		};
+
+		it51xxx_sha256_module_calculation();
+	}
+
+	/* 0 <= data length < 1KiB */
+	while (rem_len) {
+		rem_len--;
+		chip_ctx.w_input[chip_ctx.w_input_index++] = pkt->in_buf[in_buf_idx++];
+
+		/*
+		 * If fill full 64byte then execute HW calculation.
+		 * If not, will execute in later finish block.
+		 */
+		if (chip_ctx.w_input_index >= SHA_SHA256_BLOCK_LEN) {
+			/* HW automatically load 64 bytes data from DLM */
+			sys_write8(IT51XXX_SHAEXEC_64_BYTE, IT51XXX_SHAECR);
+			while (sys_read8(IT51XXX_SHASR) & IT51XXX_SHABUSY) {
+			};
+
+			it51xxx_sha256_module_calculation();
+		}
+	}
+
+	chip_ctx.total_len += pkt->in_len;
+
+	if (finish) {
+		uint32_t *out_buf_ptr = (uint32_t *)pkt->out_buf;
+
+		/* Pre-processing (Padding) */
+		chip_ctx.w_input[chip_ctx.w_input_index++] = 0x80;
+		memset(&chip_ctx.w_input[chip_ctx.w_input_index], 0,
+		       SHA_SHA256_BLOCK_LEN - chip_ctx.w_input_index);
+
+		/*
+		 * Handles the boundary case of rest data:
+		 * Because the last eight bytes are bit length field of SHA256 rule.
+		 * If the data index >= 56, it needs to trigger HW to calculate,
+		 * then fill 0 data and the last eight bytes bit length, and calculate
+		 * again.
+		 */
+		if (chip_ctx.w_input_index >= 56) {
+			/* HW automatically load 64Bytes data from DLM */
+			sys_write8(IT51XXX_SHAEXEC_64_BYTE, IT51XXX_SHAECR);
+			while (sys_read8(IT51XXX_SHASR) & IT51XXX_SHABUSY) {
+			};
+
+			it51xxx_sha256_module_calculation();
+
+			memset(&chip_ctx.w_input[chip_ctx.w_input_index], 0,
+			       SHA_SHA256_BLOCK_LEN - chip_ctx.w_input_index);
+		}
+
+		/*
+		 * Since input data (big-endian) are copied 1byte by 1byte to
+		 * it51xxx memory (little-endian), so the bit length needs to
+		 * be transformed into big-endian format and then write to memory.
+		 */
+		chip_ctx.w_sha[15] = sys_cpu_to_be32(chip_ctx.total_len * 8);
+
+		/* HW automatically load 64Bytes data from DLM */
+		sys_write8(IT51XXX_SHAEXEC_64_BYTE, IT51XXX_SHAECR);
+		while (sys_read8(IT51XXX_SHASR) & IT51XXX_SHABUSY) {
+		};
+
+		it51xxx_sha256_module_calculation();
+
+		/* HW write back the hash result to DLM */
+		/* Set DLM address for input data */
+		sys_write8(((uint32_t)&chip_ctx.h) & 0xC0, IT51XXX_SHADBA0R);
+		sys_write8(((uint32_t)&chip_ctx.h) >> 8, IT51XXX_SHADBA1R);
+
+		key = irq_lock();
+
+		sys_write8(IT51XXX_SHAWB, IT51XXX_SHACR);
+		while (sys_read8(IT51XXX_SHASR) & IT51XXX_SHABUSY) {
+		};
+
+		sys_write8(IT51XXX_SHAIS, IT51XXX_SHASR);
+
+		irq_unlock(key);
+
+		for (i = 0; i < SHA_SHA256_HASH_LEN_WORDS; i++) {
+			out_buf_ptr[i] = chip_ctx.h[i];
+		}
+
+		it51xxx_sha256_init(true);
+	}
+
+	return 0;
+}
+
+static int it51xxx_hash_session_free(const struct device *dev, struct hash_ctx *ctx)
+{
+	it51xxx_sha256_init(true);
+
+	return 0;
+}
+
+static inline int it51xxx_query_hw_caps(const struct device *dev)
+{
+	return (CAP_SEPARATE_IO_BUFS | CAP_SYNC_OPS);
+}
+
+static int it51xxx_hash_begin_session(const struct device *dev, struct hash_ctx *ctx,
+				      enum hash_algo algo)
+{
+	if (algo != CRYPTO_HASH_ALGO_SHA256) {
+		LOG_ERR("Unsupported algorithm");
+		return -EINVAL;
+	}
+
+	if (ctx->flags & ~(it51xxx_query_hw_caps(dev))) {
+		LOG_ERR("Unsupported flag");
+		return -EINVAL;
+	}
+
+	it51xxx_sha256_init(true);
+	ctx->hash_hndlr = it51xxx_hash_handler;
+
+	return 0;
+}
+
+static int it51xxx_sha_init(const struct device *dev)
+{
+	it51xxx_sha256_init(true);
+
+	/* Select SHA-2 Family, SHA-256 */
+	sys_write8(IT51XXX_SHA256, IT51XXX_SHASETR);
+
+	/* SHA interrupt disable */
+	sys_write8(sys_read8(IT51XXX_SHASR) & ~IT51XXX_SHAIE, IT51XXX_SHASR);
+
+	return 0;
+}
+
+static DEVICE_API(crypto, it51xxx_crypto_api) = {
+	.hash_begin_session = it51xxx_hash_begin_session,
+	.hash_free_session = it51xxx_hash_session_free,
+	.query_hw_caps = it51xxx_query_hw_caps,
+};
+
+DEVICE_DT_INST_DEFINE(0, &it51xxx_sha_init, NULL, NULL, NULL, POST_KERNEL,
+		      CONFIG_CRYPTO_INIT_PRIORITY, &it51xxx_crypto_api);
+BUILD_ASSERT(DT_NUM_INST_STATUS_OKAY(DT_DRV_COMPAT) == 1, "support only one sha compatible node");
diff --git a/dts/bindings/crypto/ite,it51xxx-sha.yaml b/dts/bindings/crypto/ite,it51xxx-sha.yaml
@@ -0,0 +1,12 @@
+# Copyright (c) 2025 ITE Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+description: ITE IT51XXX Crypto SHA accelerator.
+
+compatible: "ite,it51xxx-sha"
+
+include: base.yaml
+
+properties:
+  reg:
+    required: true
diff --git a/dts/riscv/ite/it51xxx.dtsi b/dts/riscv/ite/it51xxx.dtsi
@@ -1315,5 +1315,11 @@
 			io-channel = <3>;
 			extern-enable = <0xf016de 1>;
 		};
+
+		sha256: crypto@f03b00 {
+			compatible = "ite,it51xxx-sha";
+			reg = <0x00f03b00 0x6>;
+			status = "disabled";
+		};
 	};
 };
diff --git a/soc/ite/ec/it51xxx/Kconfig b/soc/ite/ec/it51xxx/Kconfig
@@ -40,6 +40,19 @@ config SOC_IT51XXX_USE_ILM
 	  predictable than executing from Flash directly, and some code (such as code
 	  that writes to the internal Flash) must execute out of RAM.
 
+config SOC_IT51XXX_SHA256_HW_ACCELERATE
+	bool "HW SHA256 calculation"
+	help
+	  IT51XXX HW support sha256 calculation, and its calculation is faster than FW.
+
+config SOC_IT515XX_SHA256_DLM_OFFSET
+	hex
+	default 0x03E000
+	depends on SOC_IT51XXX_SHA256_HW_ACCELERATE
+	help
+	  Due to the hardware requirements of the IT515XX, the SHA-256 data must be
+	  placed within the specific address range (0x83E000 to 0x83EFFF by default).
+
 config ILM_MAX_SIZE
 	int "ILM Size in kB"
 	default 4
diff --git a/soc/ite/ec/it51xxx/linker.ld b/soc/ite/ec/it51xxx/linker.ld
