At the 3rd RISC-V Workshop, there have been presentations by coreboot and UEFI. The below blog has some notes on these presentations:
http://riscv.org/workshop-jan2016.html
http://www.lowrisc.org/blog/2016/01/third-risc-v-workshop-day-one/
Apparently, someone is porting UEFI to RISC-V. I wonder what company is funding/doing it??