This change detects the presence of Zba, Zbb, and Zbs extensions and exports them per-hart to userspace via the hwprobe mechanism. Glibc can then use these in setting up hwcaps-based library search paths. There's a little bit of extra housekeeping here: the first change adds Zba and Zbs to the set of extensions the kernel recognizes, and the second change starts tracking ISA features per-hart (in addition to the ANDed mask of features across all harts which the kernel uses to make decisions). Now that we track the ISA information per-hart, we could even fix up /proc/cpuinfo to accurately report extension per-hart, though I've left that out of this series for now. Changes in v2: - Add Zbs as well - Add blank line before if in riscv_fill_hwcap() (Conor) - Fixed typo s/supporte/supported/ (Conor) - Fixed copypasta s/IMA_ZBB/EXT_ZBB/ (Conor) - Added Zbs Evan Green (3): RISC-V: Add Zba, Zbs extension probing RISC-V: Track ISA extensions per hart RISC-V: hwprobe: Expose Zba, Zbb, and Zbs Documentation/riscv/hwprobe.rst | 10 ++++++ arch/riscv/include/asm/cpufeature.h | 10 ++++++ arch/riscv/include/asm/hwcap.h | 2 ++ arch/riscv/include/uapi/asm/hwprobe.h | 3 ++ arch/riscv/kernel/cpu.c | 2 ++ arch/riscv/kernel/cpufeature.c | 20 +++++++---- arch/riscv/kernel/sys_riscv.c | 48 +++++++++++++++++++++++---- 7 files changed, 82 insertions(+), 13 deletions(-) -- 2.25.1
