audk/MdePkg/Library/BaseLib/Arm/SwitchStack.S

69 lines
1.9 KiB
ArmAsm

//------------------------------------------------------------------------------
//
// Copyright (c) 2006 - 2009, Intel Corporation. All rights reserved.<BR>
// Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
// Portions copyright (c) 2011, ARM Limited. All rights reserved.<BR>
// This program and the accompanying materials
// are licensed and made available under the terms and conditions of the BSD License
// which accompanies this distribution. The full text of the license may be found at
// http://opensource.org/licenses/bsd-license.php.
//
// THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
// WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
//
//------------------------------------------------------------------------------
.text
.align 5
GCC_ASM_EXPORT(InternalSwitchStackAsm)
GCC_ASM_EXPORT(CpuPause)
/**
//
// This allows the caller to switch the stack and goes to the new entry point
//
// @param EntryPoint The pointer to the location to enter
// @param Context Parameter to pass in
// @param Context2 Parameter2 to pass in
// @param NewStack New Location of the stack
//
// @return Nothing. Goes to the Entry Point passing in the new parameters
//
VOID
EFIAPI
InternalSwitchStackAsm (
SWITCH_STACK_ENTRY_POINT EntryPoint,
VOID *Context,
VOID *Context2,
VOID *NewStack
);
**/
ASM_PFX(InternalSwitchStackAsm):
MOV LR, R0
MOV SP, R3
MOV R0, R1
MOV R1, R2
BX LR
/**
//
// Requests CPU to pause for a short period of time.
//
// Requests CPU to pause for a short period of time. Typically used in MP
// systems to prevent memory starvation while waiting for a spin lock.
//
VOID
EFIAPI
CpuPause (
VOID
)
**/
ASM_PFX(CpuPause):
nop
nop
nop
nop
nop
BX LR