Commit 40f5b078 authored by Rabin Vincent's avatar Rabin Vincent Committed by Russell King

ARM: 5772/1: Use REV and REV16 for byte swapping on ARMv6+

ARMv6 introduced the REV and REV16 instructions that reverse bytes in
words and halfwords.  Use them for the arch-specific implementation of
the byte swapping helpers on ARMv6+.
Signed-off-by: default avatarRabin Vincent <rabin@rab.in>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent a8cf81ff
...@@ -22,6 +22,24 @@ ...@@ -22,6 +22,24 @@
# define __SWAB_64_THRU_32__ # define __SWAB_64_THRU_32__
#endif #endif
#if defined(__KERNEL__) && __LINUX_ARM_ARCH__ >= 6
static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
{
__asm__ ("rev16 %0, %1" : "=r" (x) : "r" (x));
return x;
}
#define __arch_swab16 __arch_swab16
static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
{
__asm__ ("rev %0, %1" : "=r" (x) : "r" (x));
return x;
}
#define __arch_swab32 __arch_swab32
#else
static inline __attribute_const__ __u32 __arch_swab32(__u32 x) static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
{ {
__u32 t; __u32 t;
...@@ -48,3 +66,4 @@ static inline __attribute_const__ __u32 __arch_swab32(__u32 x) ...@@ -48,3 +66,4 @@ static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
#endif #endif
#endif
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