byte_swap.h revision 1.2.6.2 1 1.2.6.2 jdolecek /* $NetBSD: byte_swap.h,v 1.2.6.2 2002/09/06 08:32:35 jdolecek Exp $ */
2 1.2.6.2 jdolecek
3 1.2.6.2 jdolecek /*-
4 1.2.6.2 jdolecek * Copyright (c) 1997, 1999, 2002 The NetBSD Foundation, Inc.
5 1.2.6.2 jdolecek * All rights reserved.
6 1.2.6.2 jdolecek *
7 1.2.6.2 jdolecek * This code is derived from software contributed to The NetBSD Foundation
8 1.2.6.2 jdolecek * by Charles M. Hannum, Neil A. Carson, and Jason R. Thorpe.
9 1.2.6.2 jdolecek *
10 1.2.6.2 jdolecek * Redistribution and use in source and binary forms, with or without
11 1.2.6.2 jdolecek * modification, are permitted provided that the following conditions
12 1.2.6.2 jdolecek * are met:
13 1.2.6.2 jdolecek * 1. Redistributions of source code must retain the above copyright
14 1.2.6.2 jdolecek * notice, this list of conditions and the following disclaimer.
15 1.2.6.2 jdolecek * 2. Redistributions in binary form must reproduce the above copyright
16 1.2.6.2 jdolecek * notice, this list of conditions and the following disclaimer in the
17 1.2.6.2 jdolecek * documentation and/or other materials provided with the distribution.
18 1.2.6.2 jdolecek * 3. All advertising materials mentioning features or use of this software
19 1.2.6.2 jdolecek * must display the following acknowledgement:
20 1.2.6.2 jdolecek * This product includes software developed by the NetBSD
21 1.2.6.2 jdolecek * Foundation, Inc. and its contributors.
22 1.2.6.2 jdolecek * 4. Neither the name of The NetBSD Foundation nor the names of its
23 1.2.6.2 jdolecek * contributors may be used to endorse or promote products derived
24 1.2.6.2 jdolecek * from this software without specific prior written permission.
25 1.2.6.2 jdolecek *
26 1.2.6.2 jdolecek * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 1.2.6.2 jdolecek * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 1.2.6.2 jdolecek * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 1.2.6.2 jdolecek * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 1.2.6.2 jdolecek * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 1.2.6.2 jdolecek * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 1.2.6.2 jdolecek * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 1.2.6.2 jdolecek * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 1.2.6.2 jdolecek * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 1.2.6.2 jdolecek * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 1.2.6.2 jdolecek * POSSIBILITY OF SUCH DAMAGE.
37 1.2.6.2 jdolecek */
38 1.2.6.2 jdolecek
39 1.2.6.2 jdolecek #ifndef _ARM_BYTE_SWAP_H_
40 1.2.6.2 jdolecek #define _ARM_BYTE_SWAP_H_
41 1.2.6.2 jdolecek
42 1.2.6.2 jdolecek #include <sys/types.h>
43 1.2.6.2 jdolecek
44 1.2.6.2 jdolecek static __inline u_int32_t
45 1.2.6.2 jdolecek __byte_swap_32_variable(u_int32_t v)
46 1.2.6.2 jdolecek {
47 1.2.6.2 jdolecek u_int32_t t1;
48 1.2.6.2 jdolecek
49 1.2.6.2 jdolecek t1 = v ^ ((v << 16) | (v >> 16));
50 1.2.6.2 jdolecek t1 &= 0xff00ffff;
51 1.2.6.2 jdolecek v = (v >> 8) | (v << 24);
52 1.2.6.2 jdolecek v ^= (t1 >> 8);
53 1.2.6.2 jdolecek
54 1.2.6.2 jdolecek return (v);
55 1.2.6.2 jdolecek }
56 1.2.6.2 jdolecek
57 1.2.6.2 jdolecek static __inline u_int16_t
58 1.2.6.2 jdolecek __byte_swap_16_variable(u_int16_t v)
59 1.2.6.2 jdolecek {
60 1.2.6.2 jdolecek
61 1.2.6.2 jdolecek __asm __volatile(
62 1.2.6.2 jdolecek "mov %0, %1, ror #8\n"
63 1.2.6.2 jdolecek "orr %0, %0, %0, lsr #16\n"
64 1.2.6.2 jdolecek "bic %0, %0, %0, lsl #16"
65 1.2.6.2 jdolecek : "=r" (v)
66 1.2.6.2 jdolecek : "0" (v));
67 1.2.6.2 jdolecek
68 1.2.6.2 jdolecek return (v);
69 1.2.6.2 jdolecek }
70 1.2.6.2 jdolecek
71 1.2.6.2 jdolecek #ifdef __OPTIMIZE__
72 1.2.6.2 jdolecek
73 1.2.6.2 jdolecek #define __byte_swap_32_constant(x) \
74 1.2.6.2 jdolecek ((((x) & 0xff000000) >> 24) | \
75 1.2.6.2 jdolecek (((x) & 0x00ff0000) >> 8) | \
76 1.2.6.2 jdolecek (((x) & 0x0000ff00) << 8) | \
77 1.2.6.2 jdolecek (((x) & 0x000000ff) << 24))
78 1.2.6.2 jdolecek
79 1.2.6.2 jdolecek #define __byte_swap_16_constant(x) \
80 1.2.6.2 jdolecek ((((x) & 0xff00) >> 8) | \
81 1.2.6.2 jdolecek (((x) & 0x00ff) << 8))
82 1.2.6.2 jdolecek
83 1.2.6.2 jdolecek #define __byte_swap_32(x) \
84 1.2.6.2 jdolecek (__builtin_constant_p((x)) ? \
85 1.2.6.2 jdolecek __byte_swap_32_constant(x) : __byte_swap_32_variable(x))
86 1.2.6.2 jdolecek
87 1.2.6.2 jdolecek #define __byte_swap_16(x) \
88 1.2.6.2 jdolecek (__builtin_constant_p((x)) ? \
89 1.2.6.2 jdolecek __byte_swap_16_constant(x) : __byte_swap_16_variable(x))
90 1.2.6.2 jdolecek
91 1.2.6.2 jdolecek #else
92 1.2.6.2 jdolecek
93 1.2.6.2 jdolecek #define __byte_swap_32(x) __byte_swap_32_variable(x)
94 1.2.6.2 jdolecek #define __byte_swap_16(x) __byte_swap_16_variable(x)
95 1.2.6.2 jdolecek
96 1.2.6.2 jdolecek #endif /* __OPTIMIZE__ */
97 1.2.6.2 jdolecek
98 1.2.6.2 jdolecek #endif /* _ARM_BYTE_SWAP_H_ */
99