ipc: Add multiple instances RPMsg

This patch implements a service that adds multiple instances
capabilities to RPMsg.
Each instance is allocated a separate piece of shared memory.
Multiple instances provide independent message processing.
Each instance has its own work_q.

Signed-off-by: Marcin Jeliński <marcin.jelinski@nordicsemi.no>

include/ipc/rpmsg_multi_instance.h

@@ -0,0 +1,193 @@
+/*
+ * Copyright (c) 2021 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_INCLUDE_RPMSG_MULTIPLE_INSTANCE_H_
+#define ZEPHYR_INCLUDE_RPMSG_MULTIPLE_INSTANCE_H_
+
+#include <openamp/open_amp.h>
+#include <metal/sys.h>
+#include <metal/device.h>
+#include <metal/alloc.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief RPMsg multiple instance API
+ * @defgroup rpmsg_multiple_instance_api RPMsg multiple instance APIs
+ * @{
+ */
+
+#define VDEV_START_ADDR     CONFIG_RPMSG_MULTI_INSTANCE_SHM_BASE_ADDRESS
+#define VDEV_SIZE           CONFIG_RPMSG_MULTI_INSTANCE_SHM_SIZE
+
+#define SHM_START_ADDR      VDEV_START_ADDR
+#define SHM_SIZE            VDEV_SIZE
+
+#define VRING_ALIGNMENT     (4)     /**< Alignment of vring buffer. */
+#define VDEV_STATUS_SIZE    (0x4)   /**< Size of status region. */
+
+/** @brief Event callback structure.
+ *
+ *  It is registered during endpoint registration.
+ *  This structure is packed into the endpoint configuration.
+ */
+struct rpmsg_mi_cb {
+	/** @brief Bind was successful.
+	 *
+	 *  @param priv Private user data.
+	 */
+	void (*bound)(void *priv);
+
+	/** @brief New packet arrived.
+	 *
+	 *  @param data Pointer to data buffer.
+	 *  @param len Length of @a data.
+	 *  @param priv Private user data.
+	 */
+	void (*received)(const void *data, size_t len, void *priv);
+};
+
+/** @brief Endpoint instance. */
+struct rpmsg_mi_ept {
+
+	/** Name of endpoint. */
+	const char *name;
+
+	/** RPMsg endpoint. */
+	struct rpmsg_endpoint ep;
+
+	/** Event callback structure. */
+	struct rpmsg_mi_cb *cb;
+
+	/** Private user data. */
+	void *priv;
+
+	/** Endpoint was bound. */
+	volatile bool bound;
+
+	/** Linked list node. */
+	sys_snode_t node;
+};
+
+/** @brief Endpoint configuration. */
+struct rpmsg_mi_ept_cfg {
+
+	/** Name of endpoint. */
+	const char *name;
+
+	/** Event callback structure. */
+	struct rpmsg_mi_cb *cb;
+
+	/** Private user data. */
+	void *priv;
+};
+
+/** @brief Struct describing the context of the RPMsg instanece. */
+struct rpmsg_mi_ctx {
+	const char *name;
+	struct k_work_q ipm_work_q;
+	struct k_work ipm_work;
+
+	const struct device *ipm_tx_handle;
+	const struct device *ipm_rx_handle;
+
+	uint32_t shm_status_reg_addr;
+	struct metal_io_region *shm_io;
+	struct metal_device shm_device;
+	metal_phys_addr_t shm_physmap[1];
+
+	struct rpmsg_virtio_device rvdev;
+	struct rpmsg_virtio_shm_pool shpool;
+	struct rpmsg_device *rdev;
+
+	struct virtqueue *vq[2];
+	struct virtio_vring_info rvrings[2];
+	struct virtio_device vdev;
+
+	uint32_t vring_tx_addr;
+	uint32_t vring_rx_addr;
+
+	sys_slist_t endpoints;
+};
+
+/** @brief Configuration of the RPMsg instance. */
+struct rpsmg_mi_ctx_cfg {
+
+	/** Name of instance. */
+	const char *name;
+
+	/** Stack area for k_work_q. */
+	k_thread_stack_t *ipm_stack_area;
+
+	/** Size of stack area. */
+	size_t ipm_stack_size;
+
+	/** Priority of work_q. */
+	int ipm_work_q_prio;
+
+	/** Name of work_q thread. */
+	const char *ipm_thread_name;
+
+	/** Name of the TX IPM channel. */
+	const char *ipm_tx_name;
+
+	/** Name of the RX IPM channel. */
+	const char *ipm_rx_name;
+};
+
+/** @brief Initialization of RPMsg instance.
+ *
+ *  Each instance has an automatically allocated area of shared memory.
+ *
+ * @param ctx Pointer to the RPMsg instance.
+ * @param cfg Pointer to the configuration structure.
+ * @retval 0 if the operation was successful.
+ *         -EINVAL when the incorrect parameters have been passed.
+ *         -EIO when the configuration is not correct.
+ *         -ENODEV failed to get TX or RX IPM handle.
+ *         -ENOMEM when there is not enough memory to register virqueue.
+ *         < 0 on other negative errno code, reported by rpmsg.
+ */
+int rpmsg_mi_ctx_init(struct rpmsg_mi_ctx *ctx, const struct rpsmg_mi_ctx_cfg *cfg);
+
+/** @brief Register IPC endpoint.
+ *
+ *  Registers IPC endpoint to enable communication with a remote device.
+ *
+ *  @param ctx Pointer to the RPMsg instance.
+ *  @param ept Pointer to endpoint object.
+ *  @param cfg Pointer to the endpoint configuration.
+ *
+ *  @retval -EINVAL One of the parameters is incorrect.
+ *  @retval other errno code reported by rpmsg.
+ */
+int rpmsg_mi_ept_register(struct rpmsg_mi_ctx *ctx,
+			  struct rpmsg_mi_ept *ept,
+			  struct rpmsg_mi_ept_cfg *cfg);
+
+/** @brief Send data using given IPC endpoint.
+ *
+ *  Note: It is not possible to send a message of zero length.
+ *
+ *  @param ept Endpoint object.
+ *  @param data Pointer to the buffer to send through RPMsg.
+ *  @param len Number of bytes to send.
+ *
+ *  @retval Number of bytes it has sent or negative error value on failure.
+ */
+int rpmsg_mi_send(struct rpmsg_mi_ept *ept, const void *data, size_t len);
+
+/**
+ * @}
+ */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ZEPHYR_INCLUDE_RPMSG_MULTIPLE_INNSTANCE_H_ */