How do I reset the ARM Cortex-M3 in the Microsemi SmartFusion2 MSS Reset Controller?

[McLondyn]

Resetting the ARM Cortex-M3 microcontroller within the Microsemi SmartFusion2 MSS Reset Controller is achieved using the M3_RESET_N signal. This signal acts as an active-low reset input, originating from the FPGA fabric. Setting M3_RESET_N to '0' initiates the reset of the Cortex-M3. This capability allows for an extended system reset specifically for the Cortex-M3, even after the rest of the MSS has been released from reset. Implementing this extended reset, by asserting the M3_RESET_N signal, facilitates secure hardware-based code shadowing, potentially reducing boot times. Upon release from this extended reset, the Cortex-M3 begins execution of a minimal boot loader, typically sourced from the eNVM block. If code shadowing isn't being used and access to the rest of the MSS is desired, the M3_RESET_N signal can be statically tied high within the FPGA fabric. For comprehensive details on configuring and utilizing the M3_RESET_N signal in the Microsemi SmartFusion2 MSS Reset Controller, consult the Microsemi SmartFusion2 User's Guide.