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    Subject[PATCH -next v2 0/3] RISC-V: Add Bitmanip/Scalar Crypto HWCAP
    This patchset proposes a currently viable and forward
    compatible way to expose the bitmanip/scalar crypto
    capability of the platform to the userspace.

    Currently viable refers to the property that hardware
    platforms can easily modify the riscv,isa field in DT to
    tell the kernel it has the capability. Note that QEMU
    has already done so in its device tree.

    Forward compatible refers to the property that userspace
    can still detect the capability of the environment by
    using HWCAP regardless of how the mechanism changes
    below kernel in the future. I do know that it has not
    been settled how to discover a capability, but I think
    kernel has to offer some API after all, and HWCAP
    is the preferred way among other mechanisms for now.

    A note here is that the draft riscv-platform spec
    considers DT as mandatory discovery mechanism for embedded platform
    For other discovery mechanism like ACPI/SMBIOS, similar
    code path can be added but the HWCAP interface could
    remain unchanged

    More discussion on userspace discovering
    can be found on my PR to openssl
    https://github.com/openssl/openssl/pull/18197

    ---
    v2:
    * Fixed checkpatch problem found by Heiko Stuebner
    * rebased on riscv/for-next as that branch has merged
    the support of Svpbmt extension
    * Changed the order of logical ids in riscv_isa_ext_id
    to the order specified in riscv-isa-manual
    * added note on riscv-platform-spec


    Hongren (Zenithal) Zheng (3):
    RISC-V: add Bitmanip/Scalar Crypto parsing from DT
    RISC-V: uapi: add HWCAP for Bitmanip/Scalar Crypto
    RISC-V: HWCAP: parse Bitmanip/Scalar Crypto HWCAP from DT

    arch/riscv/include/asm/elf.h | 2 +
    arch/riscv/include/asm/hwcap.h | 22 +++++++-
    arch/riscv/include/uapi/asm/hwcap.h | 22 ++++++++
    arch/riscv/kernel/cpu.c | 14 +++++
    arch/riscv/kernel/cpufeature.c | 81 +++++++++++++++++++++++++----
    5 files changed, 129 insertions(+), 12 deletions(-)

    --
    2.35.1

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