lkml.org 
[lkml]   [2020]   [May]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[RFC PATCH v4 04/13] riscv: Extending cpufeature.c to detect V-extension
    Date
    From: Guo Ren <guoren@linux.alibaba.com>

    From: Guo Ren <ren_guo@c-sky.com>

    Current cpufeature.c doesn't support detecting V-extension, because
    "rv64" also contain a 'v' letter and we need to skip it.

    Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
    Reviewed-by: Anup Patel <anup@brainfault.org>
    ---
    arch/riscv/include/uapi/asm/hwcap.h | 1 +
    arch/riscv/kernel/cpufeature.c | 4 +++-
    2 files changed, 4 insertions(+), 1 deletion(-)

    diff --git a/arch/riscv/include/uapi/asm/hwcap.h b/arch/riscv/include/uapi/asm/hwcap.h
    index dee98ee28318..a913e9a38819 100644
    --- a/arch/riscv/include/uapi/asm/hwcap.h
    +++ b/arch/riscv/include/uapi/asm/hwcap.h
    @@ -21,5 +21,6 @@
    #define COMPAT_HWCAP_ISA_F (1 << ('F' - 'A'))
    #define COMPAT_HWCAP_ISA_D (1 << ('D' - 'A'))
    #define COMPAT_HWCAP_ISA_C (1 << ('C' - 'A'))
    +#define COMPAT_HWCAP_ISA_V (1 << ('V' - 'A'))

    #endif /* _UAPI_ASM_RISCV_HWCAP_H */
    diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
    index a5ad00043104..c8527d770c98 100644
    --- a/arch/riscv/kernel/cpufeature.c
    +++ b/arch/riscv/kernel/cpufeature.c
    @@ -30,6 +30,7 @@ void riscv_fill_hwcap(void)
    isa2hwcap['f'] = isa2hwcap['F'] = COMPAT_HWCAP_ISA_F;
    isa2hwcap['d'] = isa2hwcap['D'] = COMPAT_HWCAP_ISA_D;
    isa2hwcap['c'] = isa2hwcap['C'] = COMPAT_HWCAP_ISA_C;
    + isa2hwcap['v'] = isa2hwcap['V'] = COMPAT_HWCAP_ISA_V;

    elf_hwcap = 0;

    @@ -44,7 +45,8 @@ void riscv_fill_hwcap(void)
    continue;
    }

    - for (i = 0; i < strlen(isa); ++i)
    + /* Skip rv64/rv32 to support v/V:vector */
    + for (i = 4; i < strlen(isa); ++i)
    this_hwcap |= isa2hwcap[(unsigned char)(isa[i])];

    /*
    --
    2.26.2
    \
     
     \ /
      Last update: 2020-05-26 09:03    [W:4.029 / U:0.172 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site