1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
|
/*
* linux/include/asm-arm/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_BYTEORDER_H
#define __ASM_ARM_BYTEORDER_H
#include <linux/compiler.h>
#include <asm/types.h>
static inline __attribute_const__ __u32 ___arch__swab32(__u32 x)
{
__u32 t;
if (__builtin_constant_p(x)) {
t = x ^ ((x << 16) | (x >> 16)); /* eor r1,r0,r0,ror #16 */
} else {
/*
* 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));
}
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(x) ___arch__swab32(x)
#if !defined(__STRICT_ANSI__) || defined(__KERNEL__)
# define __BYTEORDER_HAS_U64__
# define __SWAB_64_THRU_32__
#endif
#ifdef __ARMEB__
#include <linux/byteorder/big_endian.h>
#else
#include <linux/byteorder/little_endian.h>
#endif
#endif
|
