drivers: crc: create ambiq crc driver

boards/ambiq/apollo4p_blue_kxr_evb/apollo4p_blue_kxr_evb.dts

@@ -28,6 +28,7 @@
 		sw1 = &button1;
 		rtc = &rtc0;
 		pwm-led0 = &pwm_led0;
+		crc0 = &crc32;
 	};
 
 	leds {
@@ -189,6 +190,10 @@ zephyr_udc0: &usb {
 	status = "okay";
 };
 
+&crc32 {
+	status = "okay";
+};
+
 &gpio0_31 {
 	status = "okay";
 };

boards/ambiq/apollo4p_evb/apollo4p_evb-pinctrl.dtsi

@@ -222,11 +222,4 @@
 				 ambiq,pull-up-ohms = <12000>;
 		};
 	};
-	pwm2_default: pwm2_default{
-		group1 {
-			pinmux = <CT30_P30>;
-			drive-open-drain;
-			drive-strength = "0.5";
-		};
-	};
 };

boards/ambiq/apollo4p_evb/apollo4p_evb.dts

@@ -28,6 +28,7 @@
 		rtc = &rtc0;
 		sdhc0 = &sdio0;
 		pwm-led0 = &pwm_led0;
+		crc0 = &crc32;
 	};
 
 	leds {
@@ -187,6 +188,10 @@
 	};
 };
 
+&crc32 {
+	status = "okay";
+};
+
 zephyr_udc0: &usb {
 	vddusb33-gpios = <&gpio96_127 7 (GPIO_PULL_UP)>;
 	vddusb0p9-gpios = <&gpio96_127 5 (GPIO_PULL_UP)>;

boards/ambiq/apollo510_eb/apollo510_eb.dts

@@ -28,6 +28,7 @@
 		sdhc0 = &sdio0;
 		sdhc1 = &sdio1;
 		eeprom-0 = &i2c_eeprom;
+		crc0 = &crc32;
 	};
 
 	sram0: memory@SSRAM_BASE_NAME {
@@ -354,3 +355,7 @@ zephyr_udc0: &usb {
 		};
 	};
 };
+
+&crc32 {
+	status = "okay";
+};

boards/ambiq/apollo510_evb/apollo510_evb.dts

@@ -32,6 +32,7 @@
 		sw0 = &button0;
 		sw1 = &button1;
 		pwm-led0 = &pwm_led0;
+		crc0 = &crc32;
 	};
 
 	sram0: memory@SSRAM_BASE_NAME {
@@ -341,3 +342,7 @@ zephyr_udc0: &usb {
 		};
 	};
 };
+
+&crc32 {
+	status = "okay";
+};

drivers/CMakeLists.txt

@@ -28,6 +28,7 @@ add_subdirectory_ifdef(CONFIG_COMPARATOR comparator)
 add_subdirectory_ifdef(CONFIG_CONSOLE console)
 add_subdirectory_ifdef(CONFIG_COREDUMP_DEVICE coredump)
 add_subdirectory_ifdef(CONFIG_COUNTER counter)
+add_subdirectory_ifdef(CONFIG_CRC crc)
 add_subdirectory_ifdef(CONFIG_CRYPTO crypto)
 add_subdirectory_ifdef(CONFIG_DAC dac)
 add_subdirectory_ifdef(CONFIG_DAI dai)

drivers/Kconfig

@@ -20,6 +20,7 @@ source "drivers/comparator/Kconfig"
 source "drivers/console/Kconfig"
 source "drivers/coredump/Kconfig"
 source "drivers/counter/Kconfig"
+source "drivers/crc/Kconfig"
 source "drivers/crypto/Kconfig"
 source "drivers/dac/Kconfig"
 source "drivers/dai/Kconfig"

drivers/crc/CMakeLists.txt

@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_library()
+zephyr_library_sources_ifdef(CONFIG_CRC_AMBIQ crc_ambiq.c)

drivers/crc/Kconfig

@@ -0,0 +1,26 @@
+# CRC configuration options
+
+# Copyright (c) 2025, Ambiq
+# SPDX-License-Identifier: Apache-2.0
+
+menuconfig CRC
+	bool "CRC drivers"
+	help
+	  Enable CRC (Cyclic Redundancy Check) driver support.
+
+if CRC
+
+# Ensure Ambiq-specific CRC Kconfig is included
+source "drivers/crc/Kconfig.ambiq"
+
+config CRC_INIT_PRIORITY
+	int "CRC devices init priority"
+	default 90
+	help
+	  CRC devices initialization priority.
+
+module = CRC
+module-str = CRC
+source "subsys/logging/Kconfig.template.log_config"
+
+endif # CRC

drivers/crc/Kconfig.ambiq

@@ -0,0 +1,11 @@
+# Ambiq CRC configuration options
+
+# Copyright (c) 2025 Ambiq
+# SPDX-License-Identifier: Apache-2.0
+
+config CRC_AMBIQ
+	bool "Ambiq Apollo4P and Apollo510 CRC support"
+	default y
+	depends on SOC_SERIES_APOLLO4X || SOC_SERIES_APOLLO5X
+	help
+	  Enable Ambiq Apollo4P and Apollo510 CRC support.

drivers/crc/crc_ambiq.c

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2025 Ambiq Micro, Inc.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT ambiq_hw_crc32
+
+#include <string.h>
+#include "soc.h"
+#include <zephyr/logging/log.h>
+#include <zephyr/device.h>
+#include <zephyr/drivers/crc/crc.h>
+
+LOG_MODULE_REGISTER(ambiq_hw_crc32, CONFIG_KERNEL_LOG_LEVEL);
+
+static int crc_ambiq_get_crc32(const struct device *dev, const void *startAddr, uint32_t sizeBytes,
+			       uint32_t *pCrc)
+{
+	ARG_UNUSED(dev);
+
+	/*
+	 * Validate input parameters
+	 */
+	if (sizeBytes == 0 || startAddr == NULL || pCrc == NULL) {
+		return -EINVAL;
+	}
+
+	/*
+	 * If the CRC is already running then return an error
+	 */
+	if (SECURITY->CTRL_b.ENABLE) {
+		return -EBUSY;
+	}
+
+	/*
+	 * Generate the CRC
+	 */
+	am_hal_crc32((uint32_t)startAddr, sizeBytes, pCrc);
+
+	return 0;
+}
+
+static int crc_ambiq_init(const struct device *dev)
+{
+	ARG_UNUSED(dev);
+
+	/* Any hardware init can be performed here if needed. */
+	return 0;
+}
+
+static const struct crc_driver_api crc_ambiq_api_funcs = {
+	.get_crc = crc_ambiq_get_crc32,
+};
+
+DEVICE_DT_INST_DEFINE(0, crc_ambiq_init, NULL, NULL, NULL, POST_KERNEL,
+					  CONFIG_KERNEL_INIT_PRIORITY_DEFAULT,
+					  &crc_ambiq_api_funcs);

dts/arm/ambiq/ambiq_apollo4p.dtsi

@@ -111,6 +111,12 @@
 			};
 		};
 
+		crc32: crc32@40030030 {
+			compatible = "ambiq,hw-crc32";
+			reg = <0x40030030 0x4>;
+			status = "disabled";
+		};
+
 		stimer0: stimer@40008800 {
 			compatible = "ambiq,stimer";
 			reg = <0x40008800 0x80>;

dts/arm/ambiq/ambiq_apollo4p_blue.dtsi

@@ -713,6 +713,12 @@
 			status = "disabled";
 		};
 
+		crc32: crc32@40030030 {
+			compatible = "ambiq,hw-crc32";
+			reg = <0x40030030 0x4>;
+			status = "disabled";
+		};
+
 	};
 };
 

dts/arm/ambiq/ambiq_apollo510.dtsi

@@ -155,6 +155,12 @@
 			status = "disabled";
 		};
 
+		crc32: crc32@40030030 {
+			compatible = "ambiq,hw-crc32";
+			reg = <0x40030030 0x4>;
+			status = "disabled";
+		};
+
 		stimer0: stimer@STIMER_BASE_NAME {
 			compatible = "ambiq,stimer";
 			reg = <STIMER_REG_BASE STIMER_REG_SIZE>;

dts/bindings/binding-types.txt

@@ -32,6 +32,7 @@ comparator	Comparator
 coredump	Core dump
 counter	Counter
 cpu	CPU (Central Processing Unit)
+crc	Cyclic Redundancy Check
 crypto	Cryptographic accelerator
 dac	DAC (Digital to Analog Converter)
 dai	DAI (Digital Audio Interface)

dts/bindings/crc/ambiq,hw-crc32.yaml

@@ -0,0 +1,16 @@
+# Copyright (c) 2025, Ambiq
+# Author, Richard S Wheatley
+# SPDX-License-Identifier: Apache-2.0
+
+description: |
+    Hardware CRC32 Cyclic Redundancy Check Module.
+
+    This module implements a hardware-based CRC32 calculation.
+
+compatible: "ambiq,hw-crc32"
+
+include: base.yaml
+
+properties:
+  reg:
+    required: true

include/zephyr/drivers/crc/crc.h

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2025, Ambiq Micro Inc. <www.ambiq.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_INCLUDE_DRIVERS_CRC_H_
+#define ZEPHYR_INCLUDE_DRIVERS_CRC_H_
+
+#include <zephyr/device.h>
+#include <stdint.h>
+#include <errno.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Driver callback: compute CRC32 over a memory region */
+typedef int (*crc_get_fn)(const struct device *dev,
+			  const void *start_addr,
+			  uint32_t size_bytes,
+			  uint32_t *out_crc);
+
+/* Public driver API struct */
+struct crc_driver_api {
+	crc_get_fn get_crc;
+};
+
+/* Convenience inline wrapper that calls the device API */
+static inline int crc_driver_get_crc(const struct device *dev,
+				     const void *start_addr,
+				     uint32_t size_bytes,
+				     uint32_t *out_crc)
+{
+	const struct crc_driver_api *api;
+
+	if (dev == NULL) {
+		return -EINVAL;
+	}
+
+	api = (const struct crc_driver_api *)dev->api;
+	if (!api || !api->get_crc) {
+		return -ENOSYS;
+	}
+
+	return api->get_crc(dev, start_addr, size_bytes, out_crc);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ZEPHYR_INCLUDE_DRIVERS_CRC_H_ */

samples/drivers/crc/CMakeLists.txt

@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(crc)
+
+target_sources(app PRIVATE src/main.c)

samples/drivers/crc/README.rst

@@ -0,0 +1,46 @@
+.. _crc-sample:
+
+CRC Sample
+##########
+
+Overview
+********
+
+This sample demonstrates how to use the CRC (Cyclic Redundancy Check) driver API.
+The sample calculates CRC32 checksums over test data and displays the results.
+
+Building and Running
+********************
+
+This sample can be found under :zephyr_file:`samples/drivers/crc` in the Zephyr tree.
+
+The sample will work on any board that has a CRC driver enabled and configured.
+For Ambiq Apollo4P and Apollo510 boards, the sample uses the hardware CRC32 module.
+
+Supported boards:
+- apollo4p_evb
+- apollo4p_blue_kxr_evb
+- apollo510_evb
+- apollo510_eb
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/drivers/crc
+   :board: apollo4p_evb
+   :goals: build flash
+   :compact:
+
+Sample Output
+=============
+
+.. code-block:: console
+
+    *** Booting Zephyr OS build v3.x.x ***
+    [00:00:00.000,000] <inf> crc_sample: CRC Sample starting...
+    [00:00:00.000,000] <inf> crc_sample: Testing CRC device: crc32@40030030
+    [00:00:00.001,000] <inf> crc_sample: CRC32 of 256 bytes: 0x12345678
+    [00:00:00.002,000] <inf> crc_sample: CRC test completed successfully
+
+References
+**********
+
+- :ref:`crc_api`

samples/drivers/crc/prj.conf

@@ -0,0 +1,3 @@
+CONFIG_CRC=y
+CONFIG_CRC_AMBIQ=y
+CONFIG_LOG=y

samples/drivers/crc/sample.yaml

@@ -0,0 +1,20 @@
+sample:
+  name: CRC Sample
+  description: Sample application demonstrating CRC driver usage
+common:
+  tags: crc drivers
+  platform_allow:
+    - apollo4p_evb
+    - apollo4p_blue_kxr_evb
+    - apollo510_evb
+    - apollo510_eb
+  integration_platforms:
+    - apollo4p_evb
+tests:
+  sample.drivers.crc:
+    tags: crc drivers
+    platform_allow:
+      - apollo4p_evb
+      - apollo4p_blue_kxr_evb
+      - apollo510_evb
+      - apollo510_eb