diff options
| -rw-r--r-- | arch/arm/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm/include/asm/bitrev.h | 20 |
2 files changed, 21 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 97d07ed60a0b..c3a986d45125 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -29,6 +29,7 @@ config ARM select HANDLE_DOMAIN_IRQ select HARDIRQS_SW_RESEND select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT) + select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL select HAVE_ARCH_KGDB select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT) diff --git a/arch/arm/include/asm/bitrev.h b/arch/arm/include/asm/bitrev.h new file mode 100644 index 000000000000..ec291c350ea3 --- /dev/null +++ b/arch/arm/include/asm/bitrev.h @@ -0,0 +1,20 @@ +#ifndef __ASM_BITREV_H +#define __ASM_BITREV_H + +static __always_inline __attribute_const__ u32 __arch_bitrev32(u32 x) +{ + __asm__ ("rbit %0, %1" : "=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 |