Systems and methods for host-side configuration of a host channel adapter (HCA). An exemplary embodiment can provide a HCA, including a control circuit with a processor and a memory, and at least one port operative to connect the HCA to a network fabric. Additionally, the HCA can include a subnet management agent (SMA) that executes on the HCA, and a software driver for the HCA that includes a control application programming interface (API) that exposes functionality to hyper-privileged software executing on a host. The hyper-privileged software can set, through the control API, configurable variables stored in the memory of the HCA. Based on the value of the set variables, the HCA can operate in one of a legacy mode or one or more other modes.