InOsEmuPkg: Unix emulator now compiles for IA-32.

[mirror_edk2.git] / InOsEmuPkg / Sec / Ia32 / SwitchRam.S

#------------------------------------------------------------------------------\r
#\r
# Copyright (c) 2007, Intel Corporation. All rights reserved.<BR>\r
# This program and the accompanying materials\r
# are licensed and made available under the terms and conditions of the BSD License\r
# which accompanies this distribution.  The full text of the license may be found at\r
# http:#opensource.org/licenses/bsd-license.php\r
#\r
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
#\r
# Module Name:\r
#\r
#   Stack.asm\r
#\r
# Abstract:\r
#\r
#   Switch the stack from temporary memory to permenent memory.\r
#\r
#------------------------------------------------------------------------------\r
\r
 .text\r
 \r
\r
//  EFI_STATUS\r
//  EFIAPI\r
//  SecTemporaryRamSupport (\r
//    IN CONST EFI_PEI_SERVICES   **PeiServices,         // %rcx\r
//    IN EFI_PHYSICAL_ADDRESS     TemporaryMemoryBase,   // %rdx\r
//    IN EFI_PHYSICAL_ADDRESS     PermanentMemoryBase,   // %r8 \r
//    IN UINTN                    CopySize               // %r9\r
//    )\r
//\r
ASM_GLOBAL ASM_PFX(SecTemporaryRamSupport)\r
ASM_PFX(SecTemporaryRamSupport):\r
//------------------------------------------------------------------------------\r
// VOID\r
// EFIAPI\r
// SecSwitchStack (\r
//   UINT32   TemporaryMemoryBase,\r
//   UINT32   PermenentMemoryBase\r
//   )//\r
//------------------------------------------------------------------------------    \r
\r
    //\r
    // Save three register: eax, ebx, ecx\r
    //\r
    push  %eax\r
    push  %ebx\r
    push  %ecx\r
    push  %edx\r
\r
#if 0    \r
// Port me to GAS syntax\r
    //\r
    // !!CAUTION!! this function addresss is pushed into stack after\r
    // migration of whole temporary memory, so need save it to permenent\r
    // memory at first!\r
    //\r
    \r
    mov   ebx, [esp + 20]          // Save the first parameter\r
    mov   ecx, [esp + 24]          // Save the second parameter\r
    \r
    //\r
    // Save this functions return address into permenent memory at first.\r
    // Then, Fixup the esp point to permenent memory\r
    //\r
    mov   eax, esp\r
    sub   eax, ebx\r
    add   eax, ecx\r
    mov   edx, dword ptr [esp]         // copy pushed registers value to permenent memory\r
    mov   dword ptr [eax], edx    \r
    mov   edx, dword ptr [esp + 4]\r
    mov   dword ptr [eax + 4], edx    \r
    mov   edx, dword ptr [esp + 8]\r
    mov   dword ptr [eax + 8], edx    \r
    mov   edx, dword ptr [esp + 12]\r
    mov   dword ptr [eax + 12], edx    \r
    mov   edx, dword ptr [esp + 16]    // Update this functions return address into permenent memory\r
    mov   dword ptr [eax + 16], edx    \r
    mov   esp, eax                     // From now, esp is pointed to permenent memory\r
        \r
    //\r
    // Fixup the ebp point to permenent memory\r
    //\r
    mov   eax, ebp\r
    sub   eax, ebx\r
    add   eax, ecx\r
    mov   ebp, eax                // From now, ebp is pointed to permenent memory\r
    \r
    //\r
    // Fixup callees ebp point for PeiDispatch\r
    //\r
    mov   eax, dword ptr [ebp]\r
    sub   eax, ebx\r
    add   eax, ecx\r
    mov   dword ptr [ebp], eax    // From now, Temporarys PPI callers stack is in permenent memory\r
#endif\r
    pop   %edx\r
    pop   %ecx\r
    pop   %ebx\r
    pop   %eax\r
    ret\r