[U-Boot] difference between ft_board_setup() and ft_system_setup()

[Hannes Schmelzer]

hi,

i've seen today that there is some kconfig option to switch on 
CONFIG_OF_SYSTEM_SETUP,
which turns on calling some ft_system_setup() function before booting 
the OS.

In the days before this my meaning was to implement all things which i 
have to modify dynamically within ft_board_setup().

What is the purpose of ft_system_setup, which thing should be 
implemented here and which things should stay in ft_board_setup?

many thanks and best regards,
Hannes