Contributed two core platform features to the flipperdevices/u-boot repository, focusing on enhancing boot security and system reliability for the Vexpress64 board. Developed and enabled the DM_RNG virtio RNG driver to provide early entropy to the kernel, supporting security mechanisms such as address layout randomization. Additionally, implemented SYSRESET and SYSRESET_PSCI support by configuring relevant kernel options and refactoring reset logic to leverage the sysreset uclass, improving system reset handling for capsule-on-disk workflows. The work was carried out in C, drawing on expertise in driver development, embedded systems, and kernel configuration, with an emphasis on maintainable, platform-specific enhancements.