1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _LINUX_BITREV_H |
3 | #define _LINUX_BITREV_H |
4 | |
5 | #include <linux/types.h> |
6 | |
7 | #ifdef CONFIG_HAVE_ARCH_BITREVERSE |
8 | #include <asm/bitrev.h> |
9 | |
10 | #define __bitrev32 __arch_bitrev32 |
11 | #define __bitrev16 __arch_bitrev16 |
12 | #define __bitrev8 __arch_bitrev8 |
13 | |
14 | #else |
15 | extern u8 const byte_rev_table[256]; |
16 | static inline u8 __bitrev8(u8 byte) |
17 | { |
18 | return byte_rev_table[byte]; |
19 | } |
20 | |
21 | static inline u16 __bitrev16(u16 x) |
22 | { |
23 | return (__bitrev8(byte: x & 0xff) << 8) | __bitrev8(byte: x >> 8); |
24 | } |
25 | |
26 | static inline u32 __bitrev32(u32 x) |
27 | { |
28 | return (__bitrev16(x: x & 0xffff) << 16) | __bitrev16(x: x >> 16); |
29 | } |
30 | |
31 | #endif /* CONFIG_HAVE_ARCH_BITREVERSE */ |
32 | |
33 | #define __bitrev8x4(x) (__bitrev32(swab32(x))) |
34 | |
35 | #define __constant_bitrev32(x) \ |
36 | ({ \ |
37 | u32 ___x = x; \ |
38 | ___x = (___x >> 16) | (___x << 16); \ |
39 | ___x = ((___x & (u32)0xFF00FF00UL) >> 8) | ((___x & (u32)0x00FF00FFUL) << 8); \ |
40 | ___x = ((___x & (u32)0xF0F0F0F0UL) >> 4) | ((___x & (u32)0x0F0F0F0FUL) << 4); \ |
41 | ___x = ((___x & (u32)0xCCCCCCCCUL) >> 2) | ((___x & (u32)0x33333333UL) << 2); \ |
42 | ___x = ((___x & (u32)0xAAAAAAAAUL) >> 1) | ((___x & (u32)0x55555555UL) << 1); \ |
43 | ___x; \ |
44 | }) |
45 | |
46 | #define __constant_bitrev16(x) \ |
47 | ({ \ |
48 | u16 ___x = x; \ |
49 | ___x = (___x >> 8) | (___x << 8); \ |
50 | ___x = ((___x & (u16)0xF0F0U) >> 4) | ((___x & (u16)0x0F0FU) << 4); \ |
51 | ___x = ((___x & (u16)0xCCCCU) >> 2) | ((___x & (u16)0x3333U) << 2); \ |
52 | ___x = ((___x & (u16)0xAAAAU) >> 1) | ((___x & (u16)0x5555U) << 1); \ |
53 | ___x; \ |
54 | }) |
55 | |
56 | #define __constant_bitrev8x4(x) \ |
57 | ({ \ |
58 | u32 ___x = x; \ |
59 | ___x = ((___x & (u32)0xF0F0F0F0UL) >> 4) | ((___x & (u32)0x0F0F0F0FUL) << 4); \ |
60 | ___x = ((___x & (u32)0xCCCCCCCCUL) >> 2) | ((___x & (u32)0x33333333UL) << 2); \ |
61 | ___x = ((___x & (u32)0xAAAAAAAAUL) >> 1) | ((___x & (u32)0x55555555UL) << 1); \ |
62 | ___x; \ |
63 | }) |
64 | |
65 | #define __constant_bitrev8(x) \ |
66 | ({ \ |
67 | u8 ___x = x; \ |
68 | ___x = (___x >> 4) | (___x << 4); \ |
69 | ___x = ((___x & (u8)0xCCU) >> 2) | ((___x & (u8)0x33U) << 2); \ |
70 | ___x = ((___x & (u8)0xAAU) >> 1) | ((___x & (u8)0x55U) << 1); \ |
71 | ___x; \ |
72 | }) |
73 | |
74 | #define bitrev32(x) \ |
75 | ({ \ |
76 | u32 __x = x; \ |
77 | __builtin_constant_p(__x) ? \ |
78 | __constant_bitrev32(__x) : \ |
79 | __bitrev32(__x); \ |
80 | }) |
81 | |
82 | #define bitrev16(x) \ |
83 | ({ \ |
84 | u16 __x = x; \ |
85 | __builtin_constant_p(__x) ? \ |
86 | __constant_bitrev16(__x) : \ |
87 | __bitrev16(__x); \ |
88 | }) |
89 | |
90 | #define bitrev8x4(x) \ |
91 | ({ \ |
92 | u32 __x = x; \ |
93 | __builtin_constant_p(__x) ? \ |
94 | __constant_bitrev8x4(__x) : \ |
95 | __bitrev8x4(__x); \ |
96 | }) |
97 | |
98 | #define bitrev8(x) \ |
99 | ({ \ |
100 | u8 __x = x; \ |
101 | __builtin_constant_p(__x) ? \ |
102 | __constant_bitrev8(__x) : \ |
103 | __bitrev8(__x) ; \ |
104 | }) |
105 | #endif /* _LINUX_BITREV_H */ |
106 | |