1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2001 David E. O'Brien
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  *	@(#)endian.h	8.1 (Berkeley) 6/10/93
31  * $NetBSD: endian.h,v 1.7 1999/08/21 05:53:51 simonb Exp $
32  * $FreeBSD$
33  */
34 /*
35  * Portions copyright (c) 2018, ARM Limited and Contributors.
36  * All rights reserved.
37  */
38 
39 #ifndef ENDIAN__H
40 #define ENDIAN__H
41 
42 #include <stdint.h>
43 
44 /*
45  * Definitions for byte order, according to byte significance from low
46  * address to high.
47  */
48 #define	_LITTLE_ENDIAN  1234    /* LSB first: i386, vax */
49 #define	_BIG_ENDIAN     4321    /* MSB first: 68000, ibm, net */
50 #define	_PDP_ENDIAN     3412    /* LSB first in word, MSW first in long */
51 
52 #define	_BYTE_ORDER	_LITTLE_ENDIAN
53 
54 #if __BSD_VISIBLE
55 #define	LITTLE_ENDIAN   _LITTLE_ENDIAN
56 #define	BIG_ENDIAN      _BIG_ENDIAN
57 #define	PDP_ENDIAN      _PDP_ENDIAN
58 #define	BYTE_ORDER      _BYTE_ORDER
59 #endif
60 
61 #define	_QUAD_HIGHWORD  1
62 #define	_QUAD_LOWWORD 0
63 #define	__ntohl(x)        (__bswap32(x))
64 #define	__ntohs(x)        (__bswap16(x))
65 #define	__htonl(x)        (__bswap32(x))
66 #define	__htons(x)        (__bswap16(x))
67 
68 static __inline uint64_t
__bswap64(uint64_t x)69 __bswap64(uint64_t x)
70 {
71 	uint64_t ret;
72 
73 	__asm __volatile("rev %0, %1\n"
74 			 : "=&r" (ret), "+r" (x));
75 
76 	return (ret);
77 }
78 
79 static __inline uint32_t
__bswap32_var(uint32_t v)80 __bswap32_var(uint32_t v)
81 {
82 	uint32_t ret;
83 
84 	__asm __volatile("rev32 %x0, %x1\n"
85 			 : "=&r" (ret), "+r" (v));
86 
87 	return (ret);
88 }
89 
90 static __inline uint16_t
__bswap16_var(uint16_t v)91 __bswap16_var(uint16_t v)
92 {
93 	uint32_t ret;
94 
95 	__asm __volatile("rev16 %w0, %w1\n"
96 			 : "=&r" (ret), "+r" (v));
97 
98 	return ((uint16_t)ret);
99 }
100 
101 #ifdef __OPTIMIZE__
102 
103 #define	__bswap32_constant(x)	\
104     ((((x) & 0xff000000U) >> 24) |	\
105      (((x) & 0x00ff0000U) >>  8) |	\
106      (((x) & 0x0000ff00U) <<  8) |	\
107      (((x) & 0x000000ffU) << 24))
108 
109 #define	__bswap16_constant(x)	\
110     ((((x) & 0xff00) >> 8) |		\
111      (((x) & 0x00ff) << 8))
112 
113 #define	__bswap16(x)	\
114     ((uint16_t)(__builtin_constant_p(x) ?	\
115      __bswap16_constant((uint16_t)(x)) :	\
116      __bswap16_var(x)))
117 
118 #define	__bswap32(x)	\
119     ((uint32_t)(__builtin_constant_p(x) ? 	\
120      __bswap32_constant((uint32_t)(x)) :	\
121      __bswap32_var(x)))
122 
123 #else
124 #define	__bswap16(x)	__bswap16_var(x)
125 #define	__bswap32(x)	__bswap32_var(x)
126 
127 #endif /* __OPTIMIZE__ */
128 #endif /* ENDIAN__H */
129