#include "interfaces-impl/arch_registers_impl.h"
The list of these registers is usually provided by the chip vendor in the form of one or more header files.
To include these registers in a portable way, here we only include arch_registers_impl.h, which will be an header file in arch/arch name/board name/interfaces_impl
The usual implementation of arch_registers_impl.h is simply to include the header files provided by the chip vendor.