xref: /freebsd/sys/arm/include/endian.h (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
1 /*-
2  * Copyright (c) 2001 David E. O'Brien
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  * 3. Neither the name of the University nor the names of its contributors
13  *    may be used to endorse or promote products derived from this software
14  *    without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  *	@(#)endian.h	8.1 (Berkeley) 6/10/93
29  * $NetBSD: endian.h,v 1.7 1999/08/21 05:53:51 simonb Exp $
30  * $FreeBSD$
31  */
32 
33 #ifndef _ENDIAN_H_
34 #define	_ENDIAN_H_
35 
36 #include <sys/_types.h>
37 
38 /*
39  * Definitions for byte order, according to byte significance from low
40  * address to high.
41  */
42 #define _LITTLE_ENDIAN  1234    /* LSB first: i386, vax */
43 #define _BIG_ENDIAN     4321    /* MSB first: 68000, ibm, net */
44 #define _PDP_ENDIAN     3412    /* LSB first in word, MSW first in long */
45 
46 #ifdef __ARMEB__
47 #define _BYTE_ORDER	_BIG_ENDIAN
48 #else
49 #define	_BYTE_ORDER	_LITTLE_ENDIAN
50 #endif /* __ARMEB__ */
51 
52 #if __BSD_VISIBLE
53 #define LITTLE_ENDIAN   _LITTLE_ENDIAN
54 #define BIG_ENDIAN      _BIG_ENDIAN
55 #define PDP_ENDIAN      _PDP_ENDIAN
56 #define BYTE_ORDER      _BYTE_ORDER
57 #endif
58 
59 #ifdef __ARMEB__
60 #define _QUAD_HIGHWORD 0
61 #define _QUAD_LOWWORD 1
62 #define __ntohl(x)	((__uint32_t)(x))
63 #define __ntohs(x)	((__uint16_t)(x))
64 #define __htonl(x)	((__uint32_t)(x))
65 #define __htons(x)	((__uint16_t)(x))
66 #else
67 #define _QUAD_HIGHWORD  1
68 #define _QUAD_LOWWORD 0
69 #define __ntohl(x)        (__bswap32(x))
70 #define __ntohs(x)        (__bswap16(x))
71 #define __htonl(x)        (__bswap32(x))
72 #define __htons(x)        (__bswap16(x))
73 #endif /* __ARMEB__ */
74 
75 static __inline __uint64_t
76 __bswap64(__uint64_t _x)
77 {
78 
79 	return ((_x >> 56) | ((_x >> 40) & 0xff00) | ((_x >> 24) & 0xff0000) |
80 	    ((_x >> 8) & 0xff000000) | ((_x << 8) & ((__uint64_t)0xff << 32)) |
81 	    ((_x << 24) & ((__uint64_t)0xff << 40)) |
82 	    ((_x << 40) & ((__uint64_t)0xff << 48)) | ((_x << 56)));
83 }
84 
85 static __inline __uint32_t
86 __bswap32_var(__uint32_t v)
87 {
88 	__uint32_t t1;
89 
90 	__asm __volatile("eor %1, %0, %0, ror #16\n"
91 	    		"bic %1, %1, #0x00ff0000\n"
92 			"mov %0, %0, ror #8\n"
93 			"eor %0, %0, %1, lsr #8\n"
94 			 : "+r" (v), "=r" (t1));
95 
96 	return (v);
97  }
98 
99 static __inline __uint16_t
100 __bswap16_var(__uint16_t v)
101 {
102 	__uint32_t ret = v & 0xffff;
103 
104 	__asm __volatile(
105 	    "mov    %0, %0, ror #8\n"
106 	    "orr    %0, %0, %0, lsr #16\n"
107 	    "bic    %0, %0, %0, lsl #16"
108 	    : "+r" (ret));
109 
110 	return ((__uint16_t)ret);
111 }
112 
113 #ifdef __OPTIMIZE__
114 
115 #define __bswap32_constant(x)	\
116     ((((x) & 0xff000000U) >> 24) |	\
117      (((x) & 0x00ff0000U) >>  8) |	\
118      (((x) & 0x0000ff00U) <<  8) |	\
119      (((x) & 0x000000ffU) << 24))
120 
121 #define __bswap16_constant(x)	\
122     ((((x) & 0xff00) >> 8) |		\
123      (((x) & 0x00ff) << 8))
124 
125 #define __bswap16(x)	\
126     ((__uint16_t)(__builtin_constant_p(x) ?	\
127      __bswap16_constant(x) :			\
128      __bswap16_var(x)))
129 
130 #define __bswap32(x)	\
131     ((__uint32_t)(__builtin_constant_p(x) ? 	\
132      __bswap32_constant(x) :			\
133      __bswap32_var(x)))
134 
135 #else
136 #define __bswap16(x)	__bswap16_var(x)
137 #define __bswap32(x)	__bswap32_var(x)
138 
139 #endif /* __OPTIMIZE__ */
140 #endif /* !_ENDIAN_H_ */
141