1 /** @file 2 GCC inline implementation of BaseSynchronizationLib processor specific functions. 3 4 Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR> 5 Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR> 6 This program and the accompanying materials 7 are licensed and made available under the terms and conditions of the BSD License 8 which accompanies this distribution. The full text of the license may be found at 9 http://opensource.org/licenses/bsd-license.php. 10 11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 13 14 **/ 15 16 17 18 /** 19 Performs an atomic increment of an 32-bit unsigned integer. 20 21 Performs an atomic increment of the 32-bit unsigned integer specified by 22 Value and returns the incremented value. The increment operation must be 23 performed using MP safe mechanisms. The state of the return value is not 24 guaranteed to be MP safe. 25 26 @param Value A pointer to the 32-bit value to increment. 27 28 @return The incremented value. 29 30 **/ 31 UINT32 32 EFIAPI 33 InternalSyncIncrement ( 34 IN volatile UINT32 *Value 35 ) 36 { 37 UINT32 Result; 38 39 __asm__ __volatile__ ( 40 "lock \n\t" 41 "incl %2 \n\t" 42 "movl %2, %%eax " 43 : "=a" (Result), // %0 44 "=m" (*Value) // %1 45 : "m" (*Value) // %2 46 : "memory", 47 "cc" 48 ); 49 50 return Result; 51 52 } 53 54 55 /** 56 Performs an atomic decrement of an 32-bit unsigned integer. 57 58 Performs an atomic decrement of the 32-bit unsigned integer specified by 59 Value and returns the decremented value. The decrement operation must be 60 performed using MP safe mechanisms. The state of the return value is not 61 guaranteed to be MP safe. 62 63 @param Value A pointer to the 32-bit value to decrement. 64 65 @return The decremented value. 66 67 **/ 68 UINT32 69 EFIAPI 70 InternalSyncDecrement ( 71 IN volatile UINT32 *Value 72 ) 73 { 74 UINT32 Result; 75 76 __asm__ __volatile__ ( 77 "lock \n\t" 78 "decl %2 \n\t" 79 "movl %2, %%eax " 80 : "=a" (Result), // %0 81 "=m" (*Value) // %1 82 : "m" (*Value) // %2 83 : "memory", 84 "cc" 85 ); 86 87 return Result; 88 } 89 90 /** 91 Performs an atomic compare exchange operation on a 16-bit unsigned integer. 92 93 Performs an atomic compare exchange operation on the 16-bit unsigned integer 94 specified by Value. If Value is equal to CompareValue, then Value is set to 95 ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue, 96 then Value is returned. The compare exchange operation must be performed using 97 MP safe mechanisms. 98 99 100 @param Value A pointer to the 16-bit value for the compare exchange 101 operation. 102 @param CompareValue 16-bit value used in compare operation. 103 @param ExchangeValue 16-bit value used in exchange operation. 104 105 @return The original *Value before exchange. 106 107 **/ 108 UINT16 109 EFIAPI 110 InternalSyncCompareExchange16 ( 111 IN OUT volatile UINT16 *Value, 112 IN UINT16 CompareValue, 113 IN UINT16 ExchangeValue 114 ) 115 { 116 117 __asm__ __volatile__ ( 118 " \n\t" 119 "lock \n\t" 120 "cmpxchgw %1, %2 \n\t" 121 : "=a" (CompareValue) 122 : "q" (ExchangeValue), 123 "m" (*Value), 124 "0" (CompareValue) 125 : "memory", 126 "cc" 127 ); 128 129 return CompareValue; 130 } 131 132 /** 133 Performs an atomic compare exchange operation on a 32-bit unsigned integer. 134 135 Performs an atomic compare exchange operation on the 32-bit unsigned integer 136 specified by Value. If Value is equal to CompareValue, then Value is set to 137 ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue, 138 then Value is returned. The compare exchange operation must be performed using 139 MP safe mechanisms. 140 141 142 @param Value A pointer to the 32-bit value for the compare exchange 143 operation. 144 @param CompareValue 32-bit value used in compare operation. 145 @param ExchangeValue 32-bit value used in exchange operation. 146 147 @return The original *Value before exchange. 148 149 **/ 150 UINT32 151 EFIAPI 152 InternalSyncCompareExchange32 ( 153 IN OUT volatile UINT32 *Value, 154 IN UINT32 CompareValue, 155 IN UINT32 ExchangeValue 156 ) 157 { 158 159 __asm__ __volatile__ ( 160 " \n\t" 161 "lock \n\t" 162 "cmpxchgl %1, %2 \n\t" 163 : "=a" (CompareValue) // %0 164 : "q" (ExchangeValue), // %1 165 "m" (*Value), // %2 166 "0" (CompareValue) // %4 167 : "memory", 168 "cc" 169 ); 170 171 return CompareValue; 172 } 173 174 /** 175 Performs an atomic compare exchange operation on a 64-bit unsigned integer. 176 177 Performs an atomic compare exchange operation on the 64-bit unsigned integer specified 178 by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and 179 CompareValue is returned. If Value is not equal to CompareValue, then Value is returned. 180 The compare exchange operation must be performed using MP safe mechanisms. 181 182 183 @param Value A pointer to the 64-bit value for the compare exchange 184 operation. 185 @param CompareValue 64-bit value used in compare operation. 186 @param ExchangeValue 64-bit value used in exchange operation. 187 188 @return The original *Value before exchange. 189 190 **/ 191 UINT64 192 EFIAPI 193 InternalSyncCompareExchange64 ( 194 IN OUT volatile UINT64 *Value, 195 IN UINT64 CompareValue, 196 IN UINT64 ExchangeValue 197 ) 198 { 199 __asm__ __volatile__ ( 200 " \n\t" 201 "push %%ebx \n\t" 202 "movl %2,%%ebx \n\t" 203 "lock \n\t" 204 "cmpxchg8b (%1) \n\t" 205 "pop %%ebx \n\t" 206 : "+A" (CompareValue) // %0 207 : "S" (Value), // %1 208 "r" ((UINT32) ExchangeValue), // %2 209 "c" ((UINT32) (ExchangeValue >> 32)) // %3 210 : "memory", 211 "cc" 212 ); 213 214 return CompareValue; 215 } 216
