SiFive are on a path towards making libre RiscV CPUs.
RISC-V is an open, free ISA enabling a new era of processor innovation through OPEN standard collaboration.
Naturally then, these are coming with libre firmware. Rumor has it they'll be available late 2018. These should be both more libre than libreboot devices (since the hardware is o/s as well) and faster (64-bit, multicore).
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