Comment by aarroyoc
1 day ago
Loongson started with MIPS CPUs but current CPUs are not MIPS-compatible. LoongArch, while being very similar to MIPS, uses a different encoding. And some other details have changed. Better to say, MIPS-inspired.
1 day ago
Loongson started with MIPS CPUs but current CPUs are not MIPS-compatible. LoongArch, while being very similar to MIPS, uses a different encoding. And some other details have changed. Better to say, MIPS-inspired.
What are LoongArch's technical advantages over RISC-V? In other words, why should a company develop their own architecture (which then they need to push support for) rather than use an existing, free one?
Back when LoongArch was announced, RISC-V did not yet have enough (ratified) extensions to achieve feature-parity.
Even if it had, LoongArch is much more similar to MIPS. LoongSon would have had to make more microarchitectural changes before being able to tape out their first non-MIPS CPU.
I don't know about advantages, but lead times in the chip business are long and you're not turning around on a dime without very pressing reasons. Loongson has probably had many things in the pipeline as RISC-V started gaining steam. Their current processors are more advanced designs than the best known RISC-Vs.