This patch add bitrev.h file to support rbit instruction, so that we can do bitrev operation by hardware. Signed-off-by: Yalin Wang <yalin.w...@sonymobile.com> --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/bitrev.h | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+) create mode 100644 arch/arm64/include/asm/bitrev.h
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 9532f8d..b1ec1dd 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -35,6 +35,7 @@ config ARM64 select HANDLE_DOMAIN_IRQ select HARDIRQS_SW_RESEND select HAVE_ARCH_AUDITSYSCALL + select HAVE_ARCH_BITREVERSE select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_KGDB select HAVE_ARCH_TRACEHOOK diff --git a/arch/arm64/include/asm/bitrev.h b/arch/arm64/include/asm/bitrev.h new file mode 100644 index 0000000..706a209 --- /dev/null +++ b/arch/arm64/include/asm/bitrev.h @@ -0,0 +1,21 @@ +#ifndef __ASM_ARM64_BITREV_H +#define __ASM_ARM64_BITREV_H + +static __always_inline __attribute_const__ u32 __arch_bitrev32(u32 x) +{ + __asm__ ("rbit %w0, %w1" : "=r" (x) : "r" (x)); + return x; +} + +static __always_inline __attribute_const__ u16 __arch_bitrev16(u16 x) +{ + return __arch_bitrev32((u32)x) >> 16; +} + +static __always_inline __attribute_const__ u8 __arch_bitrev8(u8 x) +{ + return __arch_bitrev32((u32)x) >> 24; +} + +#endif + -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/