LoongArch Patches Updated A Tenth Time For The Linux Kernel

With the tenth iteration of the LoongArch CPU architecture patches published on Saturday, it's looking like work is settling down and this Chinese MIPS-derived, RISC-V-inspired architecture could soon be going mainline.

Just two weeks ago was the LoongArch v9 Linux kernel patches while out today is the tenth spin to address feedback and other remaining items for bringing up this code. Besides the kernel arch port maturing for LoongArch, the other prerequisite that opens up LoongArch for merging to mainline is GCC 12 having the LoongArch compiler support. Having mainline compiler support for the given CPU architecture is an obvious and necessary step before the kernel support can land for new processor architectures.

With the v10 patches, the LoongArch patches have been re-based against the latest Linux 5.18 Git state, it switches to using the generic EFI stub code, also moves over to using the generic string library and ticket spinlock implementations, drops the Zboot patch, and has other minor fixes and improvements along with updated documentation.

The Loongson 3A5000 is the first LoongArch processor but it's not too competitive against current western CPUs.

This LoongArch support is developed by Chinese vendor Loongson themselves. In its current form this CPU architecture bring-up is 23.9k lines of new code while it does also re-use some existing MIPS64 code paths too.

We'll see if LoongArch is ready for mainlining come the v5.19 kernel cycle or if it's going to bake longer or any further objections raised by upstream developers.