libkern/libkern/ppc/OSByteOrder.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #ifndef _OS_OSBYTEORDERPPC_H
  30 #define _OS_OSBYTEORDERPPC_H
  31
  32 #include <stdint.h>
  33
  34 #if !defined(OS_INLINE)
  35 # if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
  36 #        define OS_INLINE static inline
  37 # elif defined(__MWERKS__) || defined(__cplusplus)
  38 #        define OS_INLINE static inline
  39 # else
  40 #        define OS_INLINE static __inline__
  41 # endif
  42 #endif
  43
  44 /* Functions for byte reversed loads. */
  45
  46 OS_INLINE
  47 uint16_t
  48 OSReadSwapInt16(
  49     const volatile void * base,
  50     uintptr_t             byteOffset
  51 )
  52 {
  53     uint16_t result;
  54     volatile uint16_t *addr = (volatile uint16_t *)((uintptr_t)base + byteOffset);
  55
  56     __asm__ ("lhbrx %0, %2, %1"
  57              : "=r" (result)
  58              : "r"  (base), "bO" (byteOffset), "m" (*addr));
  59     return result;
  60 }
  61
  62 OS_INLINE
  63 uint32_t
  64 OSReadSwapInt32(
  65     const volatile void * base,
  66     uintptr_t             byteOffset
  67 )
  68 {
  69     uint32_t result;
  70     volatile uint32_t *addr = (volatile uint32_t *)((uintptr_t)base + byteOffset);
  71
  72     __asm__ ("lwbrx %0, %2, %1"
  73              : "=r" (result)
  74              : "r"  (base), "bO" (byteOffset), "m" (*addr));
  75     return result;
  76 }
  77
  78 OS_INLINE
  79 uint64_t
  80 OSReadSwapInt64(
  81     const volatile void * base,
  82     uintptr_t             byteOffset
  83 )
  84 {
  85     volatile uint64_t *addr = (volatile uint64_t *)((uintptr_t)base + byteOffset);
  86     union {
  87         uint64_t u64;
  88         uint32_t u32[2];
  89     } u;
  90
  91     __asm__ ("lwbrx %0, %3, %2\n\t"
  92              "lwbrx %1, %4, %2"
  93              : "=&r" (u.u32[1]), "=r" (u.u32[0])
  94              : "r"  (base), "bO" (byteOffset), "b" (byteOffset + 4), "m" (*addr));
  95     return u.u64;
  96 }
  97
  98 /* Functions for byte reversed stores. */
  99
 100 OS_INLINE
 101 void
 102 OSWriteSwapInt16(
 103     volatile void * base,
 104     uintptr_t       byteOffset,
 105     uint16_t        data
 106 )
 107 {
 108     volatile uint16_t *addr = (volatile uint16_t *)((uintptr_t)base + byteOffset);
 109
 110     __asm__ ("sthbrx %1, %3, %2"
 111              : "=m" (*addr)
 112              : "r" (data), "r" (base), "bO" (byteOffset));
 113 }
 114
 115 OS_INLINE
 116 void
 117 OSWriteSwapInt32(
 118     volatile void * base,
 119     uintptr_t       byteOffset,
 120     uint32_t        data
 121 )
 122 {
 123     volatile uint32_t *addr = (volatile uint32_t *)((uintptr_t)base + byteOffset);
 124
 125     __asm__ ("stwbrx %1, %3, %2"
 126              : "=m" (*addr)
 127              : "r" (data), "r" (base), "bO" (byteOffset));
 128 }
 129
 130 OS_INLINE
 131 void
 132 OSWriteSwapInt64(
 133     volatile void * base,
 134     uintptr_t       byteOffset,
 135     uint64_t        data
 136 )
 137 {
 138     volatile uint64_t *addr = (volatile uint64_t *)((uintptr_t)base + byteOffset);
 139     uint32_t hi = data >> 32;
 140     uint32_t lo = data & 0xffffffff;
 141
 142     __asm__ ("stwbrx %1, %4, %3\n\t"
 143              "stwbrx %2, %5, %3"
 144              : "=m" (*addr)
 145              : "r" (lo), "r" (hi), "r" (base), "bO" (byteOffset), "b" (byteOffset + 4));
 146 }
 147
 148 /* Generic byte swapping functions. */
 149
 150 OS_INLINE
 151 uint16_t
 152 _OSSwapInt16(
 153     uint16_t data
 154 )
 155 {
 156     return OSReadSwapInt16(&data, 0);
 157 }
 158
 159 OS_INLINE
 160 uint32_t
 161 _OSSwapInt32(
 162     uint32_t data
 163 )
 164 {
 165     return OSReadSwapInt32(&data, 0);
 166 }
 167
 168 OS_INLINE
 169 uint64_t
 170 _OSSwapInt64(
 171     uint64_t data
 172 )
 173 {
 174     return OSReadSwapInt64(&data, 0);
 175 }
 176
 177 #endif /* ! _OS_OSBYTEORDERPPC_H */