From 8e7a4cef71790d9406a7bd85aea6cfb12bc07d3c Mon Sep 17 00:00:00 2001 From: Yalin Wang Date: Mon, 3 Nov 2014 03:02:23 +0100 Subject: [PATCH] ARM: 8189/1: arm64:add bitrev.h file to support rbit instruction This patch add bitrev.h file to support rbit instruction, so that we can do bitrev operation by hardware. Signed-off-by: Yalin Wang Acked-by: Will Deacon Signed-off-by: Russell King --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/bitrev.h | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+) create mode 100644 arch/arm64/include/asm/bitrev.h diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index b1f9a20a3677..0ed36d1f536d 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -39,6 +39,7 @@ config ARM64 select HARDIRQS_SW_RESEND select HAVE_ALIGNED_STRUCT_PAGE if SLUB select HAVE_ARCH_AUDITSYSCALL + select HAVE_ARCH_BITREVERSE select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_KGDB select HAVE_ARCH_SECCOMP_FILTER diff --git a/arch/arm64/include/asm/bitrev.h b/arch/arm64/include/asm/bitrev.h new file mode 100644 index 000000000000..a5a0c3660137 --- /dev/null +++ b/arch/arm64/include/asm/bitrev.h @@ -0,0 +1,19 @@ +#ifndef __ASM_BITREV_H +#define __ASM_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 -- 2.45.2