add mbox backend for eGPIO

drivers/gpio/CMakeLists.txt

@@ -5,4 +5,13 @@
 #
 
 zephyr_library_amend()
-zephyr_library_sources_ifdef(CONFIG_GPIO_NRFE gpio_nrfe.c)
+
+if(CONFIG_GPIO_NRFE)
+  if(CONFIG_GPIO_NRFE_EGPIO_BACKEND_ICMSG)
+    zephyr_library_sources(gpio_nrfe_icmsg.c)
+  elseif(CONFIG_GPIO_NRFE_EGPIO_BACKEND_MBOX)
+    zephyr_library_sources(gpio_nrfe_mbox.c)
+  endif()
+
+  zephyr_library_sources(gpio_nrfe.c)
+endif()

drivers/gpio/Kconfig

@@ -18,3 +18,23 @@ config GPIO_NRFE_INIT_PRIORITY
 	  eGPIO driver device initialization priority.
 	  eGPIO initialization depends on IPC initialization which is done at the same init level and
 	  has init priority equal to 46.
+
+choice GPIO_NRFE_EGPIO_BACKEND
+	prompt "eGPIO driver backend type"
+	default GPIO_NRFE_EGPIO_BACKEND_ICMSG
+	help
+	  Select the backend type for the eGPIO driver and application.
+
+config GPIO_NRFE_EGPIO_BACKEND_MBOX
+	bool "MBOX"
+	help
+	  Use MBOX backend driver for eGPIO.
+	  The MBOX version is more resource-efficient than the ICMSG backend,
+	  but needs to have a shared structure defined as a communication channel.
+
+config GPIO_NRFE_EGPIO_BACKEND_ICMSG
+	bool "ICMSG"
+	help
+	  Use ICMSG backend driver for eGPIO.
+
+endchoice

drivers/gpio/gpio_nrfe.c

@@ -6,29 +6,10 @@
 
 #define DT_DRV_COMPAT nordic_nrf_egpio
 
-#include <drivers/gpio/nrfe_gpio.h>
 #include <zephyr/drivers/gpio.h>
 #include <zephyr/drivers/gpio/gpio_utils.h>
 
-#include <zephyr/device.h>
-
-#include <zephyr/ipc/ipc_service.h>
-
-K_SEM_DEFINE(bound_sem, 0, 1);
-
-static void ep_bound(void *priv)
-{
-	k_sem_give(&bound_sem);
-}
-
-static struct ipc_ept_cfg ep_cfg = {
-	.cb = {
-			.bound = ep_bound,
-			.received = NULL,
-		},
-};
-
-static struct ipc_ept ep;
+#include "gpio_nrfe.h"
 
 struct gpio_nrfe_data {
 	/* gpio_driver_data needs to be first */
@@ -46,16 +27,6 @@ static inline const struct gpio_nrfe_cfg *get_port_cfg(const struct device *port
 	return port->config;
 }
 
-static int gpio_send(nrfe_gpio_data_packet_t *msg)
-{
-	if (ipc_service_send(&ep, (void *)(&msg), sizeof(nrfe_gpio_data_packet_t))
-		== sizeof(nrfe_gpio_data_packet_t)) {
-		return 0;
-	} else {
-		return -EIO;
-	}
-}
-
 static int gpio_nrfe_pin_configure(const struct device *port, gpio_pin_t pin, gpio_flags_t flags)
 {
 	nrfe_gpio_data_packet_t msg = {.opcode = NRFE_GPIO_PIN_CONFIGURE,
@@ -112,25 +83,6 @@ static int gpio_nrfe_port_toggle_bits(const struct device *port, gpio_port_pins_
 	return gpio_send(&msg);
 }
 
-static int gpio_nrfe_init(const struct device *port)
-{
-	const struct device *ipc0_instance = DEVICE_DT_GET(DT_NODELABEL(ipc0));
-	int ret = ipc_service_open_instance(ipc0_instance);
-
-	if ((ret < 0) && (ret != -EALREADY)) {
-		return ret;
-	}
-
-	ret = ipc_service_register_endpoint(ipc0_instance, &ep, &ep_cfg);
-	if (ret < 0) {
-		return ret;
-	}
-
-	k_sem_take(&bound_sem, K_FOREVER);
-
-	return 0;
-}
-
 static const struct gpio_driver_api gpio_nrfe_drv_api_funcs = {
 	.pin_configure = gpio_nrfe_pin_configure,
 	.port_set_masked_raw = gpio_nrfe_port_set_masked_raw,

drivers/gpio/gpio_nrfe.h

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2024, Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#ifndef GPIO_NRFE_H__
+#define GPIO_NRFE_H__
+
+#include <drivers/gpio/nrfe_gpio.h>
+#include <zephyr/device.h>
+
+#if !defined(CONFIG_GPIO_NRFE_EGPIO_BACKEND_ICMSG) && !defined(CONFIG_GPIO_NRFE_EGPIO_BACKEND_MBOX)
+#error "Configure communication backend type"
+#endif
+
+int gpio_send(nrfe_gpio_data_packet_t *msg);
+int gpio_nrfe_init(const struct device *port);
+
+#endif /* GPIO_NRFE_H__ */

drivers/gpio/gpio_nrfe_icmsg.c

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2024, Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <zephyr/drivers/gpio.h>
+#include <zephyr/drivers/gpio/gpio_utils.h>
+#include <zephyr/ipc/ipc_service.h>
+
+#include "gpio_nrfe.h"
+
+#if defined(CONFIG_MULTITHREADING)
+K_SEM_DEFINE(bound_sem, 0, 1);
+#else
+static volatile uint32_t bound_sem = 1;
+#endif
+
+static void ep_bound(void *priv)
+{
+#if defined(CONFIG_MULTITHREADING)
+	k_sem_give(&bound_sem);
+#else
+	bound_sem = 0;
+#endif
+}
+
+static struct ipc_ept_cfg ep_cfg = {
+	.cb = {
+		.bound = ep_bound,
+		.received = NULL,
+	},
+};
+
+static struct ipc_ept ep;
+
+int gpio_send(nrfe_gpio_data_packet_t *msg)
+{
+	if (ipc_service_send(&ep, (void *)msg, sizeof(nrfe_gpio_data_packet_t)) ==
+	    sizeof(nrfe_gpio_data_packet_t)) {
+		return 0;
+	} else {
+		return -EIO;
+	}
+}
+
+int gpio_nrfe_init(const struct device *port)
+{
+	const struct device *ipc0_instance = DEVICE_DT_GET(DT_NODELABEL(ipc0));
+	int ret = ipc_service_open_instance(ipc0_instance);
+
+	if ((ret < 0) && (ret != -EALREADY)) {
+		return ret;
+	}
+
+	ret = ipc_service_register_endpoint(ipc0_instance, &ep, &ep_cfg);
+	if (ret < 0) {
+		return ret;
+	}
+
+#if defined(CONFIG_MULTITHREADING)
+	k_sem_take(&bound_sem, K_FOREVER);
+#else
+	while (bound_sem != 0) {
+	}
+#endif
+
+	return 0;
+}

drivers/gpio/gpio_nrfe_mbox.c

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2024, Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <zephyr/drivers/gpio.h>
+#include <zephyr/drivers/gpio/gpio_utils.h>
+#include <zephyr/drivers/mbox.h>
+#include <zephyr/sys/printk.h>
+
+#include "gpio_nrfe.h"
+
+static const struct mbox_dt_spec tx_channel = MBOX_DT_SPEC_GET(DT_PATH(mbox_consumer), tx);
+static nrfe_gpio_mbox_data_t *tx_data =
+	(nrfe_gpio_mbox_data_t *)((uint8_t *)(DT_REG_ADDR(DT_NODELABEL(sram_tx))));
+#define MAX_MSG_SIZE (DT_REG_SIZE(DT_NODELABEL(sram_tx)))
+
+int gpio_send(nrfe_gpio_data_packet_t *msg)
+{
+	printk("Sending opcode: %d, pin %d, port %d, flag: %d\n", msg->opcode, msg->pin, msg->port,
+	       msg->flags);
+	/* Try and get lock */
+	if (atomic_flag_test_and_set(&tx_data->lock.locked)) {
+		/* Return -1 in case lock is not acquired (used by other core)*/
+		return -1;
+	}
+
+	memcpy((void *)&tx_data->data, (void *)msg, sizeof(nrfe_gpio_data_packet_t));
+	tx_data->lock.data_size = sizeof(nrfe_gpio_data_packet_t);
+
+	/* Release lock */
+	atomic_flag_clear(&tx_data->lock.locked);
+
+	return mbox_send_dt(&tx_channel, NULL);
+}
+
+int gpio_nrfe_init(const struct device *port)
+{
+	return 0;
+}

include/drivers/gpio/nrfe_gpio.h

@@ -8,6 +8,7 @@
 #define NRFE_GPIO_H
 
 #include <drivers/nrfx_common.h>
+#include <sdp/nrfe_common.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -32,6 +33,11 @@ typedef struct __packed {
 			 */
 } nrfe_gpio_data_packet_t;
 
+typedef struct __packed {
+	nrfe_shared_data_lock_t lock;
+	nrfe_gpio_data_packet_t data;
+} nrfe_gpio_mbox_data_t;
+
 #ifdef __cplusplus
 }
 #endif

include/sdp/nrfe_common.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#ifndef NRFE_COMMON_H__
+#define NRFE_COMMON_H__
+
+#include <stdatomic.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct __packed {
+	atomic_bool locked;
+	uint32_t data_size;
+} nrfe_shared_data_lock_t;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* NRFE_COMMON_H__ */