1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * arch/arm/include/asm/byteorder.h
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * ARM Endian-ness. In little endian mode, the data bus is connected such
6*4882a593Smuzhiyun * that byte accesses appear as:
7*4882a593Smuzhiyun * 0 = d0...d7, 1 = d8...d15, 2 = d16...d23, 3 = d24...d31
8*4882a593Smuzhiyun * and word accesses (data or instruction) appear as:
9*4882a593Smuzhiyun * d0...d31
10*4882a593Smuzhiyun *
11*4882a593Smuzhiyun * When in big endian mode, byte accesses appear as:
12*4882a593Smuzhiyun * 0 = d24...d31, 1 = d16...d23, 2 = d8...d15, 3 = d0...d7
13*4882a593Smuzhiyun * and word accesses (data or instruction) appear as:
14*4882a593Smuzhiyun * d0...d31
15*4882a593Smuzhiyun */
16*4882a593Smuzhiyun #ifndef __ASM_ARM_SWAB_H
17*4882a593Smuzhiyun #define __ASM_ARM_SWAB_H
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun #include <uapi/asm/swab.h>
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun #if __LINUX_ARM_ARCH__ >= 6
22*4882a593Smuzhiyun
__arch_swahb32(__u32 x)23*4882a593Smuzhiyun static inline __attribute_const__ __u32 __arch_swahb32(__u32 x)
24*4882a593Smuzhiyun {
25*4882a593Smuzhiyun __asm__ ("rev16 %0, %1" : "=r" (x) : "r" (x));
26*4882a593Smuzhiyun return x;
27*4882a593Smuzhiyun }
28*4882a593Smuzhiyun #define __arch_swahb32 __arch_swahb32
29*4882a593Smuzhiyun #define __arch_swab16(x) ((__u16)__arch_swahb32(x))
30*4882a593Smuzhiyun
__arch_swab32(__u32 x)31*4882a593Smuzhiyun static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
32*4882a593Smuzhiyun {
33*4882a593Smuzhiyun __asm__ ("rev %0, %1" : "=r" (x) : "r" (x));
34*4882a593Smuzhiyun return x;
35*4882a593Smuzhiyun }
36*4882a593Smuzhiyun #define __arch_swab32 __arch_swab32
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun #endif
39*4882a593Smuzhiyun #endif
40