diff options
| author | Yalin Wang <Yalin.Wang@sonymobile.com> | 2015-01-16 02:45:55 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-01-16 14:06:18 +0000 |
| commit | 0b7857dbeb256d1a9c0c606ec4b5f417e159040b (patch) | |
| tree | 00d423118f36a70a1439582d316e42c1dd0bef68 /arch | |
| parent | 8e7a4cef71790d9406a7bd85aea6cfb12bc07d3c (diff) | |
| download | linux-0b7857dbeb256d1a9c0c606ec4b5f417e159040b.tar.bz2 | |
ARM: 8287/1: 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 <yalin.wang@sonymobile.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
| -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 |