1 /* $NetBSD: byte_swap.h,v 1.5 2020/04/04 21:13:20 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2014 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matt Thomas of 3am Software Foundry.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #ifndef _RISCV_BYTE_SWAP_H_
33 #define _RISCV_BYTE_SWAP_H_
34
35 #ifdef _LOCORE
36
37 #define BSWAP16(_src, _dst, _tmp) \
38 andi _dst, _src, 0xff ;\
39 slli _dst, _dst, 8 ;\
40 srli _tmp, _src, 8 ;\
41 and _tmp, _tmp, 0xff ;\
42 ori _dst, _dst, _tmp
43
44 #define BSWAP32(_src, _dst, _tmp) \
45 li v1, 0xff00 ;\
46 slli _dst, _src, 24 ;\
47 srli _tmp, _src, 24 ;\
48 ori _dst, _dst, _tmp ;\
49 and _tmp, _src, v1 ;\
50 slli _tmp, _src, 8 ;\
51 ori _dst, _dst, _tmp ;\
52 srli _tmp, _src, 8 ;\
53 and _tmp, _tmp, v1 ;\
54 ori _dst, _dst, _tmp
55
56 #else
57
58 #include <sys/types.h>
59 __BEGIN_DECLS
60
61 #define __BYTE_SWAP_U64_VARIABLE __byte_swap_u64_variable
62 static __inline uint64_t
__byte_swap_u64_variable(uint64_t v)63 __byte_swap_u64_variable(uint64_t v)
64 {
65 const uint64_t m1 = 0x0000ffff0000ffffull;
66 const uint64_t m0 = 0x00ff00ff00ff00ffull;
67
68 v = (v >> 32) | (v << 32);
69 v = ((v >> 16) & m1) | ((v & m1) << 16);
70 v = ((v >> 8) & m0) | ((v & m0) << 8);
71
72 return v;
73 }
74
75 #define __BYTE_SWAP_U32_VARIABLE __byte_swap_u32_variable
76 static __inline uint32_t
__byte_swap_u32_variable(uint32_t v)77 __byte_swap_u32_variable(uint32_t v)
78 {
79 const uint32_t m = 0xff00ff;
80
81 v = (v >> 16) | (v << 16);
82 v = ((v >> 8) & m) | ((v & m) << 8);
83
84 return v;
85 }
86
87 #define __BYTE_SWAP_U16_VARIABLE __byte_swap_u16_variable
88 static __inline uint16_t
__byte_swap_u16_variable(uint16_t v)89 __byte_swap_u16_variable(uint16_t v)
90 {
91 /*LINTED*/
92 return (uint16_t)((v >> 8) | (v << 8));
93 }
94
95 __END_DECLS
96
97 #endif /* _LOCORE */
98
99 #endif /* _RISCV_BYTE_SWAP_H_ */
100