RustSBI Project Adds SpacemiT K1 (Ky X1) Processor Support

The RISC-V firmware ecosystem continues to expand as a community contributor submitted support for the SpacemiT K1 processor to the RustSBI project. This is a significant milestone for K1 platform adoption in the RISC-V bare-metal and firmware development community.

What is RustSBI?

RustSBI is a RISC-V Supervisor Binary Interface (SBI) implementation written in Rust. It provides the firmware layer between the hardware and the operating system, handling privileged operations such as timer interrupts, IPI (Inter-Processor Interrupts), and hart management. RustSBI is part of the broader RISC-V firmware ecosystem alongside OpenSBI and other SBI implementations.

K1 Support Details

The contribution adds SpacemiT K1 support to the RustSBI prototyper component. Key highlights:

• Target Board: Orange Pi RV2 (labeled SoC: Ky X1, confirmed as SpacemiT K1)
• GitHub Issue: rustsbi/rustsbi#214
• Pull Request: rustsbi/rustsbi#217
• Implementation: Based on vendor source code and DTS file analysis

Important Finding: UART Clock Rate Discrepancy

During the porting process, the contributor discovered a clock rate discrepancy:

• Orange Pi vendor DTS specifies UART clock as 1,400,000 Hz
• SpacemiT official DTSI specifies 148,570,000 Hz
• The correct value is 148,570,000 Hz (as per SpacemiT documentation)

This is an important note for anyone working with the Orange Pi RV2 board or adapting K1-based designs. Always cross-reference with the official SpacemiT DTSI files.

Why This Matters

The addition of RustSBI support for K1 means:

1. Firmware Choice: Developers can now choose between OpenSBI (default in Bianbu Linux) and RustSBI for K1-based designs
2. Bare-Metal Development: RustSBI enables Rust-based bare-metal development on K1 with memory safety guarantees
3. Ecosystem Growth: K1 joins the list of RISC-V platforms with multiple SBI implementation support
4. Community Validation: This contribution validates that the K1 platform documentation is sufficient for independent firmware porting

How to Try It

1. Clone the RustSBI repository
2. Check out the PR #217 branch
3. Build the prototyper for K1
4. Flash to your Orange Pi RV2 or K1 MUSE Pi Pro board
5. Boot your preferred RISC-V OS with RustSBI as the firmware layer

Product Relevance

The SpacemiT K1 is our flagship RISC-V SoC for networking and edge computing, featuring 8x X60 cores at 1.6GHz with 50K DMIPS performance. The growing firmware ecosystem (now including RustSBI) makes it an increasingly attractive platform for embedded developers.

For K1 development boards and technical support, visit our product page or contact us at contact@open-riscv.com.

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Source: SpacemiT Forum - RustSBI K1 Support GitHub: rustsbi/rustsbi#214 | PR #217