Schism - Splitting RV32 from arch/riscv - We Could Both Be Better as We Part Ways

Explore a proof-of-concept proposal for splitting the Linux kernel's RISC-V architecture support into separate 32-bit and 64-bit implementations during this 30-minute conference talk from the Linux Plumbers Conference. Learn about the current challenges facing RV32 (RISC-V 32-bit) support in the Linux kernel, where RV64 has become significantly more popular and better supported, leading to discussions about potentially dropping RV32 support entirely. Discover how this situation creates difficulties for companies manufacturing RV32 Linux integrated circuits, such as HPMicro's HPM63xx series and Allwinner's V821, and understand the unique requirements of RV32 users who often operate without MMU or Atomic Extension support. Examine the proposed solution of creating separate arch/riscv32 and arch/riscv64 directories, similar to the existing arm and arm64 split, which could enable features like HIGHMEM for RV32 and mechanisms comparable to ARM's kuser_helpers for pre-v5 and SuperH architectures. Gain insights into how this architectural separation could benefit both RV32 and RV64 development while addressing the production needs of companies actively using RISC-V 32-bit Linux systems.