| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051 |
- /*
- * 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 /* __ASM_ARM_SWAB_H */
|
