This is basic abstract platform and all of RISC-V system should use platform inherit from HiFiveBase, HiFiveBase declared the common way to handle interrupt. Change-Id: I52122e1c82c200d7e6012433c2535c07d427f637 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/68199 Maintainer: Jason Lowe-Power <power.jg@gmail.com> Reviewed-by: Yu-hsin Wang <yuhsingw@google.com> Tested-by: kokoro <noreply+kokoro@google.com>