We’re proud to share an important update that will foster the RISC-V ecosystem’s continued growth: the open source Supervisor Binary Interface (OpenSBI) version 0.1 has been released. OpenSBI version 0.1 is now publicly available at GitHub. OpenSBI is an open source implementation of the RISC-V Supervisor Binary Interface (SBI). SBI serves a critical purpose, enabling an operating system to interact with the supervisor execution environment (SEE). The RISC-V ISA has defined SBI to provide a cleaner interface for the supervisor OS, streamlining the process of virtualizing and bringing up new hardware platforms. Furthermore, there’s no longer a need for the Berkeley bootloader (BBL), making it much easier to use upstream OS kernels and device data. The RISC-V SBI specifications, maintained as an independent project by the RISC-V Foundation at GitHub, define the legacy SBI interface currently in use by various products as well as by RISC-V QEMU virtual machines. OpenSBI also implements SBI compliant early boot firmwares capable of handling various boot flows and payloads on various environments. OpenSBI firmwares have been tested with payloads such as U-Boot and Linux kernel, showing that these open firmwares can fully replace the legacy non-standard BBL intermediate boot loader. The OpenSBI version 0.1 release supports the following platforms:
- SiFive’s HiFive Unleashed board
- RISC-V QEMU virt and sifive_u virtual machines
- Kendryte K210 SoC based boards