genode/repos/base/src/lib/rust-targets/spec/riscv/target.json

{
    "pre-link-args": ["-mriscv=RV64IAMFD"],
    "llvm-target": "riscv-pc-genode-elf",
    "target-endian": "little",
    "target-pointer-width": "64",
    "arch": "riscv",
    "os": "genode"
}