/** @file | |
GCC inline implementation of BaseSynchronizationLib processor specific functions. | |
Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR> | |
Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR> | |
SPDX-License-Identifier: BSD-2-Clause-Patent | |
**/ | |
/** | |
Performs an atomic increment of an 32-bit unsigned integer. | |
Performs an atomic increment of the 32-bit unsigned integer specified by | |
Value and returns the incremented value. The increment operation must be | |
performed using MP safe mechanisms. | |
@param Value A pointer to the 32-bit value to increment. | |
@return The incremented value. | |
**/ | |
UINT32 | |
EFIAPI | |
InternalSyncIncrement ( | |
IN volatile UINT32 *Value | |
) | |
{ | |
UINT32 Result; | |
__asm__ __volatile__ ( | |
"movl $1, %%eax \n\t" | |
"lock \n\t" | |
"xadd %%eax, %1 \n\t" | |
"inc %%eax \n\t" | |
: "=&a" (Result), // %0 | |
"+m" (*Value) // %1 | |
: // no inputs that aren't also outputs | |
: "memory", | |
"cc" | |
); | |
return Result; | |
} | |
/** | |
Performs an atomic decrement of an 32-bit unsigned integer. | |
Performs an atomic decrement of the 32-bit unsigned integer specified by | |
Value and returns the decremented value. The decrement operation must be | |
performed using MP safe mechanisms. | |
@param Value A pointer to the 32-bit value to decrement. | |
@return The decremented value. | |
**/ | |
UINT32 | |
EFIAPI | |
InternalSyncDecrement ( | |
IN volatile UINT32 *Value | |
) | |
{ | |
UINT32 Result; | |
__asm__ __volatile__ ( | |
"movl $-1, %%eax \n\t" | |
"lock \n\t" | |
"xadd %%eax, %1 \n\t" | |
"dec %%eax \n\t" | |
: "=&a" (Result), // %0 | |
"+m" (*Value) // %1 | |
: // no inputs that aren't also outputs | |
: "memory", | |
"cc" | |
); | |
return Result; | |
} | |
/** | |
Performs an atomic compare exchange operation on a 16-bit unsigned integer. | |
Performs an atomic compare exchange operation on the 16-bit unsigned integer | |
specified by Value. If Value is equal to CompareValue, then Value is set to | |
ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue, | |
then Value is returned. The compare exchange operation must be performed using | |
MP safe mechanisms. | |
@param Value A pointer to the 16-bit value for the compare exchange | |
operation. | |
@param CompareValue 16-bit value used in compare operation. | |
@param ExchangeValue 16-bit value used in exchange operation. | |
@return The original *Value before exchange. | |
**/ | |
UINT16 | |
EFIAPI | |
InternalSyncCompareExchange16 ( | |
IN OUT volatile UINT16 *Value, | |
IN UINT16 CompareValue, | |
IN UINT16 ExchangeValue | |
) | |
{ | |
__asm__ __volatile__ ( | |
"lock \n\t" | |
"cmpxchgw %2, %1 \n\t" | |
: "+a" (CompareValue), // %0 | |
"+m" (*Value) // %1 | |
: "r" (ExchangeValue) // %2 | |
: "memory", | |
"cc" | |
); | |
return CompareValue; | |
} | |
/** | |
Performs an atomic compare exchange operation on a 32-bit unsigned integer. | |
Performs an atomic compare exchange operation on the 32-bit unsigned integer | |
specified by Value. If Value is equal to CompareValue, then Value is set to | |
ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue, | |
then Value is returned. The compare exchange operation must be performed using | |
MP safe mechanisms. | |
@param Value A pointer to the 32-bit value for the compare exchange | |
operation. | |
@param CompareValue 32-bit value used in compare operation. | |
@param ExchangeValue 32-bit value used in exchange operation. | |
@return The original *Value before exchange. | |
**/ | |
UINT32 | |
EFIAPI | |
InternalSyncCompareExchange32 ( | |
IN OUT volatile UINT32 *Value, | |
IN UINT32 CompareValue, | |
IN UINT32 ExchangeValue | |
) | |
{ | |
__asm__ __volatile__ ( | |
"lock \n\t" | |
"cmpxchgl %2, %1 \n\t" | |
: "+a" (CompareValue), // %0 | |
"+m" (*Value) // %1 | |
: "r" (ExchangeValue) // %2 | |
: "memory", | |
"cc" | |
); | |
return CompareValue; | |
} | |
/** | |
Performs an atomic compare exchange operation on a 64-bit unsigned integer. | |
Performs an atomic compare exchange operation on the 64-bit unsigned integer specified | |
by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and | |
CompareValue is returned. If Value is not equal to CompareValue, then Value is returned. | |
The compare exchange operation must be performed using MP safe mechanisms. | |
@param Value A pointer to the 64-bit value for the compare exchange | |
operation. | |
@param CompareValue 64-bit value used in compare operation. | |
@param ExchangeValue 64-bit value used in exchange operation. | |
@return The original *Value before exchange. | |
**/ | |
UINT64 | |
EFIAPI | |
InternalSyncCompareExchange64 ( | |
IN OUT volatile UINT64 *Value, | |
IN UINT64 CompareValue, | |
IN UINT64 ExchangeValue | |
) | |
{ | |
__asm__ __volatile__ ( | |
"lock \n\t" | |
"cmpxchgq %2, %1 \n\t" | |
: "+a" (CompareValue), // %0 | |
"+m" (*Value) // %1 | |
: "r" (ExchangeValue) // %2 | |
: "memory", | |
"cc" | |
); | |
return CompareValue; | |
} |