| /* |
| * 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 __ASM_ARM_SWAB_H |
| #define __ASM_ARM_SWAB_H |
| |
| |
| #include <linux/types.h> |
| |
| #if !defined(__STRICT_ANSI__) || defined(__KERNEL__) |
| # define __SWAB_64_THRU_32__ |
| #endif |
| |
| |
| static __inline__ __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 |
