Software-Defined Vehicles (SDVs) are redefining the automotive landscape by decoupling hardware from software and enabling dynamic, over-the-air updates, advanced control strategies, and real-time decision-making. To support this transformation, EV powertrain systems require high-performance computing (HPC) platforms capable of real-time control, data processing, and cross-domain communication. This paper introduces a fully SDV-compatible EV powertrain architecture built around the NXP S32E278 domain controller, which integrates a multi-core, lockstep-enabled processor specifically designed for zonal control and automotive functional safety. To meet the bandwidth and latency demands of modern SDV applications, the system replaces conventional CAN-based communication with automotive Ethernet, enabling gigabit data transfer, Time-Sensitive Networking (TSN), and low-latency coordination across software-defined control domains. The S32E executes critical functions such as field-oriented control (FOC), peak current mode control (PCMC), and dynamic power management using an autosar-compliant software stack. In addition, this work addresses emergency charging in SDVs through portable modules, mobile charging units, and over-the-air (OTA) software updates, enabled via secure real-time interfacing with the vehicle’s software stack. These emergency energy solutions are integrated into the system architecture and managed by the domain controller to ensure power restoration and vehicle operability under critical conditions. A custom hardware prototype of HPC board was developed integrating the S32E278 domain controller within a Vehicle Control Unit (VCU). The proposed architecture has been deployed and validated in a real-time vehicle environment, with experimental results demonstrating high reliability, fast control response, and seamless data synchronization between powertrain and charging modules. This work underscores the viability of domain controller–based HPC in enabling scalable, resilient, and software-centric EV powertrains—positioning it as a reference architecture for next-generation SDVs.