Early in the year with Linux 4.17 the kernel saw a port to the Andes NDS32 CPU architecture. With Linux 4.21, that CPU architecture is seeing a number of improvements.

AndesCore NDS32 is a 32-bit RISC-like architecture with clock rates hovering around 1GHz and these CPUs used by IoT applications, wearables, medical devices, and other low-power devices. Open-source support for NDS32 has existed for years by the company albeit out of tree until the kernel support landed in Linux 4.17.

With Linux 4.21, there are a number of big additions for NDS32 including support for perf, power management, FPU, hardware prefetcher, and rounding out things are also performance enhancements.

It's quite a big addition for this niche CPU architecture with more than 4,400 lines of new kernel code as part of this pull request.