libkern/libkern/ppc/OSByteOrder.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30
  31 #ifndef _OS_OSBYTEORDERPPC_H
  32 #define _OS_OSBYTEORDERPPC_H
  33
  34 #include <stdint.h>
  35
  36 #if !defined(OS_INLINE)
  37 # if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
  38 #        define OS_INLINE static inline
  39 # elif defined(__MWERKS__) || defined(__cplusplus)
  40 #        define OS_INLINE static inline
  41 # else
  42 #        define OS_INLINE static __inline__
  43 # endif
  44 #endif
  45
  46 /* Functions for byte reversed loads. */
  47
  48 OS_INLINE
  49 uint16_t
  50 OSReadSwapInt16(
  51     const volatile void * base,
  52     uintptr_t             byteOffset
  53 )
  54 {
  55     uint16_t result;
  56     volatile uint16_t *addr = (volatile uint16_t *)((uintptr_t)base + byteOffset);
  57
  58     __asm__ ("lhbrx %0, %2, %1"
  59              : "=r" (result)
  60              : "r"  (base), "bO" (byteOffset), "m" (*addr));
  61     return result;
  62 }
  63
  64 OS_INLINE
  65 uint32_t
  66 OSReadSwapInt32(
  67     const volatile void * base,
  68     uintptr_t             byteOffset
  69 )
  70 {
  71     uint32_t result;
  72     volatile uint32_t *addr = (volatile uint32_t *)((uintptr_t)base + byteOffset);
  73
  74     __asm__ ("lwbrx %0, %2, %1"
  75              : "=r" (result)
  76              : "r"  (base), "bO" (byteOffset), "m" (*addr));
  77     return result;
  78 }
  79
  80 OS_INLINE
  81 uint64_t
  82 OSReadSwapInt64(
  83     const volatile void * base,
  84     uintptr_t             byteOffset
  85 )
  86 {
  87     volatile uint64_t *addr = (volatile uint64_t *)((uintptr_t)base + byteOffset);
  88     union {
  89         uint64_t u64;
  90         uint32_t u32[2];
  91     } u;
  92
  93     __asm__ ("lwbrx %0, %3, %2\n\t"
  94              "lwbrx %1, %4, %2"
  95              : "=&r" (u.u32[1]), "=r" (u.u32[0])
  96              : "r"  (base), "bO" (byteOffset), "b" (byteOffset + 4), "m" (*addr));
  97     return u.u64;
  98 }
  99
 100 /* Functions for byte reversed stores. */
 101
 102 OS_INLINE
 103 void
 104 OSWriteSwapInt16(
 105     volatile void * base,
 106     uintptr_t       byteOffset,
 107     uint16_t        data
 108 )
 109 {
 110     volatile uint16_t *addr = (volatile uint16_t *)((uintptr_t)base + byteOffset);
 111
 112     __asm__ ("sthbrx %1, %3, %2"
 113              : "=m" (*addr)
 114              : "r" (data), "r" (base), "bO" (byteOffset));
 115 }
 116
 117 OS_INLINE
 118 void
 119 OSWriteSwapInt32(
 120     volatile void * base,
 121     uintptr_t       byteOffset,
 122     uint32_t        data
 123 )
 124 {
 125     volatile uint32_t *addr = (volatile uint32_t *)((uintptr_t)base + byteOffset);
 126
 127     __asm__ ("stwbrx %1, %3, %2"
 128              : "=m" (*addr)
 129              : "r" (data), "r" (base), "bO" (byteOffset));
 130 }
 131
 132 OS_INLINE
 133 void
 134 OSWriteSwapInt64(
 135     volatile void * base,
 136     uintptr_t       byteOffset,
 137     uint64_t        data
 138 )
 139 {
 140     volatile uint64_t *addr = (volatile uint64_t *)((uintptr_t)base + byteOffset);
 141     uint32_t hi = data >> 32;
 142     uint32_t lo = data & 0xffffffff;
 143
 144     __asm__ ("stwbrx %1, %4, %3\n\t"
 145              "stwbrx %2, %5, %3"
 146              : "=m" (*addr)
 147              : "r" (lo), "r" (hi), "r" (base), "bO" (byteOffset), "b" (byteOffset + 4));
 148 }
 149
 150 /* Generic byte swapping functions. */
 151
 152 OS_INLINE
 153 uint16_t
 154 _OSSwapInt16(
 155     uint16_t data
 156 )
 157 {
 158     return OSReadSwapInt16(&data, 0);
 159 }
 160
 161 OS_INLINE
 162 uint32_t
 163 _OSSwapInt32(
 164     uint32_t data
 165 )
 166 {
 167     return OSReadSwapInt32(&data, 0);
 168 }
 169
 170 OS_INLINE
 171 uint64_t
 172 _OSSwapInt64(
 173     uint64_t data
 174 )
 175 {
 176     return OSReadSwapInt64(&data, 0);
 177 }
 178
 179 #endif /* ! _OS_OSBYTEORDERPPC_H */