/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
 *  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 */