audk/MdePkg/Library/BaseSynchronizationLib/RiscV64/Synchronization.S

79 lines
1.9 KiB
ArmAsm

//------------------------------------------------------------------------------
//
// RISC-V synchronization functions.
//
// Copyright (c) 2020, Hewlett Packard Enterprise Development LP. All rights reserved.<BR>
//
// SPDX-License-Identifier: BSD-2-Clause-Patent
//
//------------------------------------------------------------------------------
#include <Base.h>
.data
.text
.align 3
.global ASM_PFX(InternalSyncCompareExchange32)
.global ASM_PFX(InternalSyncCompareExchange64)
.global ASM_PFX(InternalSyncIncrement)
.global ASM_PFX(InternalSyncDecrement)
//
// ompare and xchange a 32-bit value.
//
// @param a0 : Pointer to 32-bit value.
// @param a1 : Compare value.
// @param a2 : Exchange value.
//
ASM_PFX (InternalSyncCompareExchange32):
lr.w a3, (a0) // Load the value from a0 and make
// the reservation of address.
bne a3, a1, exit
sc.w a3, a2, (a0) // Write the value back to the address.
mv a3, a1
exit:
mv a0, a3
ret
.global ASM_PFX(InternalSyncCompareExchange64)
//
// Compare and xchange a 64-bit value.
//
// @param a0 : Pointer to 64-bit value.
// @param a1 : Compare value.
// @param a2 : Exchange value.
//
ASM_PFX (SyncCompareExchange64):
lr.d a3, (a0) // Load the value from a0 and make
// the reservation of address.
bne a3, a1, exit
sc.d a3, a2, (a0) // Write the value back to the address.
mv a3, a1
exit2:
mv a0, a3
ret
//
// Performs an atomic increment of an 32-bit unsigned integer.
//
// @param a0 : Pointer to 32-bit value.
//
ASM_PFX (InternalSyncIncrement):
li a1, 1
amoadd.w a2, a1, (a0)
mv a0, a2
ret
//
// Performs an atomic decrement of an 32-bit unsigned integer.
//
// @param a0 : Pointer to 32-bit value.
//
ASM_PFX (InternalSyncDecrement):
li a1, -1
amoadd.w a2, a1, (a0)
mv a0, a2
ret