The XPm_ActivateSubsystem API allows the XSDB master to request PMC to activate a subsystem. See Activation of Subsystem for more details.
This API activates a subsystem by requesting all its pre-allocation devices that are essential for it to be operational. This API accepts a target subsystem ID that needs activation, as an input argument. The format for activating a subsystem is as follows:
XPm_ActivateSubsystem(u32 Subsystem ID)
This command is only allowed from the XSDB master. Currently, only the default subsystem is supported and is automatically activated before downloading any application binaries on a specific master.