driver: hwinfo: npcx: Add hwinfo driver support in npcx family.

boards/arm/npcx7m6fb_evb/npcx7m6fb_evb_defconfig

@@ -48,6 +48,9 @@ CONFIG_ESPI=y
 # I2C Driver
 CONFIG_I2C=y
 
+# HWINFO Driver
+CONFIG_HWINFO=y
+
 # Console Driver
 CONFIG_CONSOLE=y
 CONFIG_UART_CONSOLE=y

drivers/hwinfo/CMakeLists.txt

@@ -14,4 +14,5 @@ zephyr_sources_ifdef(CONFIG_HWINFO_SAM0       hwinfo_sam0.c)
 zephyr_sources_ifdef(CONFIG_HWINFO_LITEX      hwinfo_litex.c)
 zephyr_sources_ifdef(CONFIG_HWINFO_PSOC6      hwinfo_psoc6.c)
 zephyr_sources_ifdef(CONFIG_HWINFO_GECKO      hwinfo_gecko.c)
+zephyr_sources_ifdef(CONFIG_HWINFO_NPCX       hwinfo_npcx.c)
 zephyr_sources_ifdef(CONFIG_HWINFO_SHELL hwinfo_shell.c)

drivers/hwinfo/Kconfig

@@ -108,4 +108,12 @@ config HWINFO_GECKO
 	help
 	  Enable Silabs GECKO hwinfo driver.
 
+config HWINFO_NPCX
+	bool "Nuvoton NPCX embedded controller (EC) hwinfo driver"
+	default y
+	depends on SOC_FAMILY_NPCX
+	select HWINFO_HAS_DRIVER
+	help
+	  Enable hwinfo driver for NPCX family of processors.
+
 endif

drivers/hwinfo/hwinfo_npcx.c

@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2021 Nuvoton Technology Corporation.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <device.h>
+#include <drivers/hwinfo.h>
+#include <soc.h>
+#include <string.h>
+
+/* host module instances for hardware info */
+static struct mswc_reg *const inst_mswc = (struct mswc_reg *)
+	DT_REG_ADDR_BY_NAME(DT_INST(0, nuvoton_npcx_host_sub), mswc);
+
+/**
+ * @brief Receive 8-bit value that identifies a family of devices with similar
+ *        functionality.
+ *
+ * @retval value that identifies a family of devices with similar functionality.
+ */
+static uint8_t npcx_hwinfo_family_id(void)
+{
+	return inst_mswc->SID_CR;
+}
+
+/**
+ * @brief Receive 8-bit value that identifies a device group of the family.
+ *
+ * @retval value that identifies a device group of the family.
+ */
+static uint8_t npcx_hwinfo_chip_id(void)
+{
+	return inst_mswc->SRID_CR;
+}
+
+/**
+ * @brief Receive 8-bit value that identifies a specific device of a group.
+ *
+ * @retval value that identifies a specific device of a group.
+ */
+static uint8_t npcx_hwinfo_device_id(void)
+{
+	return inst_mswc->DEVICE_ID_CR;
+}
+
+/**
+ * @brief Receive 8-bit value that identifies the device revision.
+ *
+ * @retval value that identifies the device revision.
+ */
+static uint8_t npcx_hwinfo_revision(void)
+{
+	return inst_mswc->CHPREV_CR;
+}
+
+ssize_t z_impl_hwinfo_get_device_id(uint8_t *buffer, size_t length)
+{
+	uint8_t chip_info[4];
+
+	chip_info[0] = npcx_hwinfo_family_id();
+	chip_info[1] = npcx_hwinfo_chip_id();
+	chip_info[2] = npcx_hwinfo_device_id();
+	chip_info[3] = npcx_hwinfo_revision();
+
+	if (length > sizeof(chip_info)) {
+		length = sizeof(chip_info);
+	}
+
+	memcpy(buffer, chip_info, length);
+
+	return length;
+}