RISC-V is officially supported by NetBSD (Tier II). I have not tried to install it yet (files @ Index of pub/NetBSD/NetBSD-11.0/riscv-riscv64/) , but hardware supported looks to be enough for basic headless operation.
Here is a link to the announcement (That I have quoted below): Announcing NetBSD 11.0 (July 30, 2026)
- New port to the RISC-V architecture:
- riscv - Initial support for QEMU, including Google Goldfish RTC, VirtIO (network, disk, etc) devices, virtualized audio.
- riscv - Initial basic support for the Allwinner D1 SoC (used on e.g. MangoPi MQ Pro, Allwinner Nezha), including support for GPIO and UART serial console.
- riscv - Support for the StarFive JH7110 SoC (used on e.g. VisionFive 2, STAR64), including PCI/PCIe, TRNG, pins, temperature sensors, etc.
- riscv - Support for the crash(8) kernel debugger