With the first of RISC-V RVA23-compatible hardware expected to be released in 2026, we are beginning to see more Linux developers prepare for this RVA23 profile and the now-mandated extensions. Sent out this week was an initial “request for comments” patch series on RVA23 adjustments for the Linux kernel.
Charlie Jenkins of Rivos sent out a set of ten patches for supporting the RVA23 profile in the Linux kernel. The work includes Kconfig adjustments around RISC-V CPU extension handling,adding the ZVE23X vector extension subset, building optimized kernels by passing enabled extensions as compiler flags, and adding the RVA23 profile as a Kconfig option to select all the extensions mandated by it. RVA23 as a reminder most notably mandates the “V” vector extensions as well as other newer extensions that will help in delivering high performance RISC-V processor implementations. With the RFC patches, the RVA23 profile is exposed via the RISCV_ISA_RVA23 Kconfig option.
For adding enabled RISC-V extensions to the compiler flags for building the kernel, for CPU extensions that might be supported by the hardware and detected just at run-time, they will be added to the Assembler flags but not to the compiler flags to avoid any issues.
Those interested in these RISC-V RVA23 RFC patches for the Linux kernel can find them out for review on the Linux kernel mailing list. RVA23 and other RISC-V kernel topics are also being discussed further this week at the Linux Plumbers Conference in Japan.
