API Reference

This section describes the kernel APIs and NSH commands available for RPTUN operations.

Kernel API

rptun_initialize

int rptun_initialize(FAR struct rptun_dev_s *dev)

Initialize and register an RPTUN device.

Parameters:

dev – Pointer to the RPTUN device structure with ops configured

Returns:

OK on success; a negated errno value on failure

This function creates an RPTUN instance and registers it with the system. If the device is configured for auto-start, it will also start the remote core.

rptun_boot

int rptun_boot(FAR const char *cpuname)

Start the remote CPU.

Parameters:

cpuname – Name of the remote CPU to start

Returns:

OK on success; a negated errno value on failure

Example:

/* Start remote CPU named "M33" */
ret = rptun_boot("M33");
if (ret < 0)
  {
    syslog(LOG_ERR, "Failed to boot remote CPU: %d\n", ret);
  }

rptun_poweroff

int rptun_poweroff(FAR const char *cpuname)

Stop the remote CPU.

Parameters:

cpuname – Name of the remote CPU to stop

Returns:

OK on success; a negated errno value on failure

Example:

/* Stop remote CPU named "M33" */
ret = rptun_poweroff("M33");

rptun_reset

int rptun_reset(FAR const char *cpuname, int value)

Reset the remote CPU.

Parameters:

cpuname – Name of the remote CPU to reset
value – Reset value (implementation-specific)

Returns:

OK on success; a negated errno value on failure

Example:

/* Reset remote CPU named "M33" */
ret = rptun_reset("M33", 0);

IOCTL Commands

The RPTUN character device supports the following ioctl commands:

RPTUNIOC_START

Start the remote CPU associated with this RPTUN device.

int fd = open("/dev/rptun/remote", O_RDWR);
ret = ioctl(fd, RPTUNIOC_START, 0);

RPTUNIOC_STOP

Stop the remote CPU associated with this RPTUN device.

ret = ioctl(fd, RPTUNIOC_STOP, 0);

RPTUNIOC_RESET

Reset the remote CPU associated with this RPTUN device.

int reset_value = 0;
ret = ioctl(fd, RPTUNIOC_RESET, reset_value);

NSH Commands

The rptun NSH command provides user-space control over RPTUN devices.

rptun start

Start the remote core.

nsh> rptun start /dev/rptun/<cpuname>

Example:

nsh> rptun start /dev/rptun/M33

rptun stop

Stop the remote core.

nsh> rptun stop /dev/rptun/<cpuname>

Example:

nsh> rptun stop /dev/rptun/M33

Configuration Options

The following Kconfig options are available for RPTUN:

CONFIG_RPTUN

Enable RPTUN driver support.

CONFIG_RPTUN_PRIORITY

RPTUN thread priority. Default is 224.

CONFIG_RPTUN_STACKSIZE

RPTUN thread stack size. Default is 4096.

Header Files

include/nuttx/rptun/rptun.h - Main RPTUN header file containing all structures, macros, and function prototypes.

Access Macros

The following macros are provided for accessing RPTUN operations:

/* Get local CPU name */
RPTUN_GET_LOCAL_CPUNAME(dev)

/* Get remote CPU name */
RPTUN_GET_CPUNAME(dev)

/* Get firmware path */
RPTUN_GET_FIRMWARE(dev)

/* Get address environment */
RPTUN_GET_ADDRENV(dev)

/* Get resource table */
RPTUN_GET_RESOURCE(dev)

/* Check if auto-start is enabled */
RPTUN_IS_AUTOSTART(dev)

/* Check if this is the master core */
RPTUN_IS_MASTER(dev)

/* Configure remote core */
RPTUN_CONFIG(dev, data)

/* Start remote core */
RPTUN_START(dev)

/* Stop remote core */
RPTUN_STOP(dev)

/* Send notification to remote core */
RPTUN_NOTIFY(dev, vqid)

/* Register callback for remote notifications */
RPTUN_REGISTER_CALLBACK(dev, callback, arg)

/* Unregister callback */
RPTUN_UNREGISTER_CALLBACK(dev)

/* Reset remote core */
RPTUN_RESET(dev, value)

/* Trigger panic on remote core */
RPTUN_PANIC(dev)