diff options
| author |   Angelos Mouzakitis <a.mouzakitis@virtualopensystems.com> | 2023-10-10 14:33:42 +0000 |
|---|---|---|
| committer | Angelos Mouzakitis <a.mouzakitis@virtualopensystems.com> | 2023-10-10 14:33:42 +0000 |
| commit | af1a266670d040d2f4083ff309d732d648afba2a (patch) | |
| tree | 2fc46203448ddcc6f81546d379abfaeb323575e9 /roms/edk2/MdePkg/Library/BaseLib/Arm/SwitchStack.S | |
| parent | e02cda008591317b1625707ff8e115a4841aa889 (diff) | |
Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
Diffstat (limited to 'roms/edk2/MdePkg/Library/BaseLib/Arm/SwitchStack.S')
| -rw-r--r-- | roms/edk2/MdePkg/Library/BaseLib/Arm/SwitchStack.S | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/roms/edk2/MdePkg/Library/BaseLib/Arm/SwitchStack.S b/roms/edk2/MdePkg/Library/BaseLib/Arm/SwitchStack.S new file mode 100644 index 000000000..844c9a27f --- /dev/null +++ b/roms/edk2/MdePkg/Library/BaseLib/Arm/SwitchStack.S @@ -0,0 +1,62 @@ +//------------------------------------------------------------------------------
+//
+// Copyright (c) 2006 - 2018, 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>
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+//------------------------------------------------------------------------------
+
+.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
|