Optional Modifications

The following are helper functions implemented by the test framework that perform common platform-specific tasks. A platform may choose to override these definitions.

Function : platform_get_stack()

Argument : unsigned long
Return   : unsigned long

This function returns the base address of the memory stack that has been allocated for the CPU specified by MPIDR. The size of the stack allocated to each CPU is specified by the platform defined constant PLATFORM_STACK_SIZE.

Common implementation of this function is provided in plat/common/aarch64/platform_mp_stack.S.

Function : tftf_platform_end()

Argument : void
Return   : void

This function performs any operation required by the platform to properly finish the test session.

The default implementation sends an EOT (End Of Transmission) character on the UART. This can be used to automatically shutdown the FVP models. When running on real hardware, the UART output may be parsed by an external tool looking for this character and rebooting the platform for example.

Function : tftf_plat_reset()

Argument : void
Return   : void

This function resets the platform.

The default implementation uses the ARM watchdog peripheral (SP805) to generate a watchdog timeout interrupt. This interrupt remains deliberately unserviced, which eventually asserts the reset signal.