diff options
| author | Jiri Kosina <jkosina@suse.cz> | 2012-10-28 19:28:52 +0100 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2012-10-28 19:29:19 +0100 |
| commit | 3bd7bf1f0fe14f591c089ae61bbfa9bd356f178a (patch) | |
| tree | 0058693cc9e70b7461dae551f8a19aff2efd13ca /arch/arm/include/uapi/asm/swab.h | |
| parent | f16f84937d769c893492160b1a8c3672e3992beb (diff) | |
| parent | e657e078d3dfa9f96976db7a2b5fd7d7c9f1f1a6 (diff) | |
Merge branch 'master' into for-next
Sync up with Linus' tree to be able to apply Cesar's patch
against newer version of the code.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'arch/arm/include/uapi/asm/swab.h')
| -rw-r--r-- | arch/arm/include/uapi/asm/swab.h | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/arm/include/uapi/asm/swab.h b/arch/arm/include/uapi/asm/swab.h new file mode 100644 index 00000000000..6fcb32a5c45 --- /dev/null +++ b/arch/arm/include/uapi/asm/swab.h @@ -0,0 +1,53 @@ +/* + * arch/arm/include/asm/byteorder.h + * + * ARM Endian-ness. In little endian mode, the data bus is connected such + * that byte accesses appear as: + * 0 = d0...d7, 1 = d8...d15, 2 = d16...d23, 3 = d24...d31 + * and word accesses (data or instruction) appear as: + * d0...d31 + * + * When in big endian mode, byte accesses appear as: + * 0 = d24...d31, 1 = d16...d23, 2 = d8...d15, 3 = d0...d7 + * and word accesses (data or instruction) appear as: + * d0...d31 + */ +#ifndef _UAPI__ASM_ARM_SWAB_H +#define _UAPI__ASM_ARM_SWAB_H + +#include <linux/compiler.h> +#include <linux/types.h> + +#if !defined(__STRICT_ANSI__) || defined(__KERNEL__) +# define __SWAB_64_THRU_32__ +#endif + + +#if !defined(__KERNEL__) || __LINUX_ARM_ARCH__ < 6 +static inline __attribute_const__ __u32 __arch_swab32(__u32 x) +{ + __u32 t; + +#ifndef __thumb__ + if (!__builtin_constant_p(x)) { + /* + * The compiler needs a bit of a hint here to always do the + * right thing and not screw it up to different degrees + * depending on the gcc version. + */ + asm ("eor\t%0, %1, %1, ror #16" : "=r" (t) : "r" (x)); + } else +#endif + t = x ^ ((x << 16) | (x >> 16)); /* eor r1,r0,r0,ror #16 */ + + x = (x << 24) | (x >> 8); /* mov r0,r0,ror #8 */ + t &= ~0x00FF0000; /* bic r1,r1,#0x00FF0000 */ + x ^= (t >> 8); /* eor r0,r0,r1,lsr #8 */ + + return x; +} +#define __arch_swab32 __arch_swab32 + +#endif + +#endif /* _UAPI__ASM_ARM_SWAB_H */ |
