Already there is enough trouble to get good mainline support on ARM platforms, given the vendor specific u-boot patches, kernel patches, hacks, etc.

It's interesting to see Western Digital putting their effort behind RISC-V. I will be especially interested if they release any NAS products based on RISC-V instead of ARM. However I hope that this won't mean the end of good Linux support for these devices.

If Western Digital designs and manufactures the CPUs, there is no requirement that they publish the data sheet, which could make efforts to support mainline Linux more difficult.

https://www.anandtech.com/show/12133/western-digital-to-develop-and-use-risc-v-for-controllers