3.5.1.18.2 Scalar Argument

Scalar arguments of the top-level function (e.g., void MyTopFunc(int MyScalarArg);) can also be configured via an interface pragma, with the two supported interface types, simple (default) or axi_target.

// Add at the beginning of the function definition
// Note that the stable option is only available for simple type.
#pragma HLS interface argument(<SCALAR_ARGUMENT_NAME>) type(<simple|axi_target>) stable(<false|true>)