mirror of
https://github.com/CloverHackyColor/CloverBootloader.git
synced 2024-12-04 13:23:26 +01:00
208 lines
6.0 KiB
ArmAsm
208 lines
6.0 KiB
ArmAsm
|
// Implementation of synchronization functions for ARM architecture
|
||
|
//
|
||
|
// Copyright (c) 2012-2015, ARM Limited. All rights reserved.
|
||
|
// Copyright (c) 2015, Linaro Limited. All rights reserved.
|
||
|
//
|
||
|
// SPDX-License-Identifier: BSD-2-Clause-Patent
|
||
|
//
|
||
|
//
|
||
|
|
||
|
.text
|
||
|
.align 3
|
||
|
|
||
|
GCC_ASM_EXPORT(InternalSyncCompareExchange16)
|
||
|
GCC_ASM_EXPORT(InternalSyncCompareExchange32)
|
||
|
GCC_ASM_EXPORT(InternalSyncCompareExchange64)
|
||
|
GCC_ASM_EXPORT(InternalSyncIncrement)
|
||
|
GCC_ASM_EXPORT(InternalSyncDecrement)
|
||
|
|
||
|
/**
|
||
|
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 volatile UINT16 *Value,
|
||
|
// IN UINT16 CompareValue,
|
||
|
// IN UINT16 ExchangeValue
|
||
|
// )
|
||
|
ASM_PFX(InternalSyncCompareExchange16):
|
||
|
dmb
|
||
|
|
||
|
InternalSyncCompareExchange16Again:
|
||
|
ldrexh r3, [r0]
|
||
|
cmp r3, r1
|
||
|
bne InternalSyncCompareExchange16Fail
|
||
|
|
||
|
InternalSyncCompareExchange16Exchange:
|
||
|
strexh ip, r2, [r0]
|
||
|
cmp ip, #0
|
||
|
bne InternalSyncCompareExchange16Again
|
||
|
|
||
|
InternalSyncCompareExchange16Fail:
|
||
|
dmb
|
||
|
mov r0, r3
|
||
|
bx lr
|
||
|
|
||
|
/**
|
||
|
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 volatile UINT32 *Value,
|
||
|
// IN UINT32 CompareValue,
|
||
|
// IN UINT32 ExchangeValue
|
||
|
// )
|
||
|
ASM_PFX(InternalSyncCompareExchange32):
|
||
|
dmb
|
||
|
|
||
|
InternalSyncCompareExchange32Again:
|
||
|
ldrex r3, [r0]
|
||
|
cmp r3, r1
|
||
|
bne InternalSyncCompareExchange32Fail
|
||
|
|
||
|
InternalSyncCompareExchange32Exchange:
|
||
|
strex ip, r2, [r0]
|
||
|
cmp ip, #0
|
||
|
bne InternalSyncCompareExchange32Again
|
||
|
|
||
|
InternalSyncCompareExchange32Fail:
|
||
|
dmb
|
||
|
mov r0, r3
|
||
|
bx lr
|
||
|
|
||
|
/**
|
||
|
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 volatile UINT64 *Value, // r0
|
||
|
// IN UINT64 CompareValue, // r2-r3
|
||
|
// IN UINT64 ExchangeValue // stack
|
||
|
// )
|
||
|
ASM_PFX(InternalSyncCompareExchange64):
|
||
|
push { r4-r7 }
|
||
|
ldrd r4, r5, [sp, #16]
|
||
|
dmb
|
||
|
|
||
|
InternalSyncCompareExchange64Again:
|
||
|
ldrexd r6, r7, [r0]
|
||
|
cmp r6, r2
|
||
|
cmpeq r7, r3
|
||
|
bne InternalSyncCompareExchange64Fail
|
||
|
|
||
|
InternalSyncCompareExchange64Exchange:
|
||
|
strexd ip, r4, r5, [r0]
|
||
|
cmp ip, #0
|
||
|
bne InternalSyncCompareExchange64Again
|
||
|
|
||
|
InternalSyncCompareExchange64Fail:
|
||
|
dmb
|
||
|
mov r0, r6
|
||
|
mov r1, r7
|
||
|
pop { r4-r7 }
|
||
|
bx lr
|
||
|
|
||
|
/**
|
||
|
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. The state of the return value is not
|
||
|
guaranteed to be MP safe.
|
||
|
|
||
|
@param Value A pointer to the 32-bit value to increment.
|
||
|
|
||
|
@return The incremented value.
|
||
|
|
||
|
**/
|
||
|
//UINT32
|
||
|
//EFIAPI
|
||
|
//InternalSyncIncrement (
|
||
|
// IN volatile UINT32 *Value
|
||
|
// )
|
||
|
ASM_PFX(InternalSyncIncrement):
|
||
|
dmb
|
||
|
TryInternalSyncIncrement:
|
||
|
ldrex r1, [r0]
|
||
|
add r1, r1, #1
|
||
|
strex r2, r1, [r0]
|
||
|
cmp r2, #0
|
||
|
bne TryInternalSyncIncrement
|
||
|
dmb
|
||
|
mov r0, r1
|
||
|
bx lr
|
||
|
|
||
|
/**
|
||
|
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 decrement value. The decrement operation must be
|
||
|
performed using MP safe mechanisms. The state of the return value is not
|
||
|
guaranteed to be MP safe.
|
||
|
|
||
|
@param Value A pointer to the 32-bit value to decrement.
|
||
|
|
||
|
@return The decrement value.
|
||
|
|
||
|
**/
|
||
|
//UINT32
|
||
|
//EFIAPI
|
||
|
//InternalSyncDecrement (
|
||
|
// IN volatile UINT32 *Value
|
||
|
// )
|
||
|
ASM_PFX(InternalSyncDecrement):
|
||
|
dmb
|
||
|
TryInternalSyncDecrement:
|
||
|
ldrex r1, [r0]
|
||
|
sub r1, r1, #1
|
||
|
strex r2, r1, [r0]
|
||
|
cmp r2, #0
|
||
|
bne TryInternalSyncDecrement
|
||
|
dmb
|
||
|
mov r0, r1
|
||
|
bx lr
|