drivers: Introduce a simplified remoteproc framework

Many System on Chip(SoC) solutions are complex with multiple processors
on the same die dedicated to either general purpose of specialized
functions. Many examples do exist in today's SoCs from various vendors.
Typical examples are micro controllers such as an ARM M3/M0 doing a
offload of specific function such as event integration or power
management or controlling camera etc.

Traditionally, the responsibility of loading up such a processor with a
firmware and communication has been with a High Level Operating
System(HLOS) such as Linux. However, there exists classes of products
where Linux would need to expect services from such a processor or the
delay of Linux and operating system being able to load up such a
firmware is unacceptable.

To address these needs, we need some minimal capability to load such a
system and ensure it is started prior to an Operating System(Linux or
any other) is started up.

NOTE: This is NOT meant to be a solve-all solution, instead, it tries to
address certain class of SoCs and products that need such a solution.

A very simple model is introduced here as part of the initial support
that supports microcontrollers with internal memory (no MMU, no
execution from external memory, or specific image format needs). This
basic framework can then (hopefully) be extensible to other complex SoC
processor support as need be.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Simon Glass <sjg@chromium.org>

1 files changed, 162 insertions, 0 deletions

diff --git a/include/remoteproc.h b/include/remoteproc.h
new file mode 100644
index 0000000000..c6e044d3b8
--- /dev/null
+++ b/include/remoteproc.h
@@ -0,0 +1,162 @@
+/*
+ * (C) Copyright 2015
+ * Texas Instruments Incorporated - http://www.ti.com/
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _RPROC_H_
+#define _RPROC_H_
+
+/*
+ * Note: The platform data support is not meant for use with newer
+ * platforms. This is meant only for legacy devices. This mode of
+ * initialization *will* be eventually removed once all necessary
+ * platforms have moved to dm/fdt.
+ */
+#include <dm/platdata.h>	/* For platform data support - non dt world */
+
+/**
+ * enum rproc_mem_type - What type of memory model does the rproc use
+ * @RPROC_INTERNAL_MEMORY_MAPPED: Remote processor uses own memory and is memory
+ *	mapped to the host processor over an address range.
+ *
+ * Please note that this is an enumeration of memory model of different types
+ * of remote processors. Few of the remote processors do have own internal
+ * memories, while others use external memory for instruction and data.
+ */
+enum rproc_mem_type {
+	RPROC_INTERNAL_MEMORY_MAPPED	= 0,
+};
+
+/**
+ * struct dm_rproc_uclass_pdata - platform data for a CPU
+ * @name: Platform-specific way of naming the Remote proc
+ * @mem_type: one of 'enum rproc_mem_type'
+ * @driver_plat_data: driver specific platform data that may be needed.
+ *
+ * This can be accessed with dev_get_uclass_platdata() for any UCLASS_REMOTEPROC
+ * device.
+ *
+ */
+struct dm_rproc_uclass_pdata {
+	const char *name;
+	enum rproc_mem_type mem_type;
+	void *driver_plat_data;
+};
+
+/**
+ * struct dm_rproc_ops - Operations that are provided by remote proc driver
+ * @init:	Initialize the remoteproc device invoked after probe (optional)
+ *		Return 0 on success, -ve error on fail
+ * @load:	Load the remoteproc device using data provided(mandatory)
+ *		This takes the following additional arguments.
+ *			addr- Address of the binary image to be loaded
+ *			size- Size of the binary image to be loaded
+ *		Return 0 on success, -ve error on fail
+ * @start:	Start the remoteproc device (mandatory)
+ *		Return 0 on success, -ve error on fail
+ * @stop:	Stop the remoteproc device (optional)
+ *		Return 0 on success, -ve error on fail
+ * @reset:	Reset the remote proc device (optional)
+ *		Return 0 on success, -ve error on fail
+ * @is_running:	Check if the remote processor is running(optional)
+ *		Return 0 on success, 1 if not running, -ve on others errors
+ * @ping:	Ping the remote device for basic communication check(optional)
+ *		Return 0 on success, 1 if not responding, -ve on other errors
+ */
+struct dm_rproc_ops {
+	int (*init)(struct udevice *dev);
+	int (*load)(struct udevice *dev, ulong addr, ulong size);
+	int (*start)(struct udevice *dev);
+	int (*stop)(struct udevice *dev);
+	int (*reset)(struct udevice *dev);
+	int (*is_running)(struct udevice *dev);
+	int (*ping)(struct udevice *dev);
+};
+
+/* Accessor */
+#define rproc_get_ops(dev) ((struct dm_rproc_ops *)(dev)->driver->ops)
+
+#ifdef CONFIG_REMOTEPROC
+/**
+ * rproc_init() - Initialize all bound remote proc devices
+ *
+ * Return: 0 if all ok, else appropriate error value.
+ */
+int rproc_init(void);
+
+/**
+ * rproc_is_initialized() - check to see if remoteproc devices are initialized
+ *
+ * Return: 0 if all devices are initialized, else appropriate error value.
+ */
+bool rproc_is_initialized(void);
+
+/**
+ * rproc_load() - load binary to a remote processor
+ * @id:		id of the remote processor
+ * @addr:	address in memory where the binary image is located
+ * @size:	size of the binary image
+ *
+ * Return: 0 if all ok, else appropriate error value.
+ */
+int rproc_load(int id, ulong addr, ulong size);
+
+/**
+ * rproc_start() - Start a remote processor
+ * @id:		id of the remote processor
+ *
+ * Return: 0 if all ok, else appropriate error value.
+ */
+int rproc_start(int id);
+
+/**
+ * rproc_stop() - Stop a remote processor
+ * @id:		id of the remote processor
+ *
+ * Return: 0 if all ok, else appropriate error value.
+ */
+int rproc_stop(int id);
+
+/**
+ * rproc_reset() - reset a remote processor
+ * @id:		id of the remote processor
+ *
+ * Return: 0 if all ok, else appropriate error value.
+ */
+int rproc_reset(int id);
+
+/**
+ * rproc_ping() - ping a remote processor to check if it can communicate
+ * @id:		id of the remote processor
+ *
+ * NOTE: this might need communication path available, which is not implemented
+ * as part of remoteproc framework - hook on to appropriate bus architecture to
+ * do the same
+ *
+ * Return: 0 if all ok, else appropriate error value.
+ */
+int rproc_ping(int id);
+
+/**
+ * rproc_is_running() - check to see if remote processor is running
+ * @id:		id of the remote processor
+ *
+ * NOTE: this may not involve actual communication capability of the remote
+ * processor, but just ensures that it is out of reset and executing code.
+ *
+ * Return: 0 if all ok, else appropriate error value.
+ */
+int rproc_is_running(int id);
+#else
+static inline int rproc_init(void) { return -ENOSYS; }
+static inline bool rproc_is_initialized(void) { return false; }
+static inline int rproc_load(int id, ulong addr, ulong size) { return -ENOSYS; }
+static inline int rproc_start(int id) { return -ENOSYS; }
+static inline int rproc_stop(int id) { return -ENOSYS; }
+static inline int rproc_reset(int id) { return -ENOSYS; }
+static inline int rproc_ping(int id) { return -ENOSYS; }
+static inline int rproc_is_running(int id) { return -ENOSYS; }
+#endif
+
+#endif	/* _RPROC_H_ */