Quite a lot, see item 3 below:
$ qemu-system-riscv64 -machine \?
Supported machines are:
none empty machine
sifive_e300 RISC-V Board compatible with SiFive E300 SDK
sifive_u500 RISC-V Board compatible with SiFive U500 SDK
spike_v1.10 RISC-V Spike Board (Privileged ISA v1.10)
spike_v1.9 RISC-V Spike Board (Privileged ISA v1.9.1) (default)
virt RISC-V VirtIO Board (Privileged spec v1.10)
