projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| a33a2f62 JY |
1 | ;------------------------------------------------------------------------------\r |
| 2 | ;\r | |
| 3 | ; Copyright (c) 2014, Intel Corporation. All rights reserved.<BR>\r | |
| 19486360 | 4 | ; SPDX-License-Identifier: BSD-2-Clause-Patent\r |
| a33a2f62 JY |
5 | ;\r |
| 6 | ; Abstract:\r | |
| 7 | ;\r | |
| 8 | ; Switch the stack from temporary memory to permenent memory.\r | |
| 9 | ;\r | |
| 10 | ;------------------------------------------------------------------------------\r | |
| 11 | \r | |
| 12 | .586p\r | |
| 13 | .model flat,C\r | |
| 14 | .code\r | |
| 15 | \r | |
| 16 | ;------------------------------------------------------------------------------\r | |
| 17 | ; VOID\r | |
| 18 | ; EFIAPI\r | |
| 19 | ; SecSwitchStack (\r | |
| 20 | ; UINT32 TemporaryMemoryBase,\r | |
| 21 | ; UINT32 PermenentMemoryBase\r | |
| 22 | ; );\r | |
| 23 | ;------------------------------------------------------------------------------\r | |
| 24 | SecSwitchStack PROC\r | |
| 25 | ;\r | |
| 26 | ; Save three register: eax, ebx, ecx\r | |
| 27 | ;\r | |
| 28 | push eax\r | |
| 29 | push ebx\r | |
| 30 | push ecx\r | |
| 31 | push edx\r | |
| 32 | \r | |
| 33 | ;\r | |
| 34 | ; !!CAUTION!! this function address's is pushed into stack after\r | |
| 35 | ; migration of whole temporary memory, so need save it to permenent\r | |
| 36 | ; memory at first!\r | |
| 37 | ;\r | |
| 38 | \r | |
| 39 | mov ebx, [esp + 20] ; Save the first parameter\r | |
| 40 | mov ecx, [esp + 24] ; Save the second parameter\r | |
| 41 | \r | |
| 42 | ;\r | |
| 43 | ; Save this function's return address into permenent memory at first.\r | |
| 44 | ; Then, Fixup the esp point to permenent memory\r | |
| 45 | ;\r | |
| 46 | mov eax, esp\r | |
| 47 | sub eax, ebx\r | |
| 48 | add eax, ecx\r | |
| 49 | mov edx, dword ptr [esp] ; copy pushed register's value to permenent memory\r | |
| 50 | mov dword ptr [eax], edx\r | |
| 51 | mov edx, dword ptr [esp + 4]\r | |
| 52 | mov dword ptr [eax + 4], edx\r | |
| 53 | mov edx, dword ptr [esp + 8]\r | |
| 54 | mov dword ptr [eax + 8], edx\r | |
| 55 | mov edx, dword ptr [esp + 12]\r | |
| 56 | mov dword ptr [eax + 12], edx\r | |
| 57 | mov edx, dword ptr [esp + 16] ; Update this function's return address into permenent memory\r | |
| 58 | mov dword ptr [eax + 16], edx\r | |
| 59 | mov esp, eax ; From now, esp is pointed to permenent memory\r | |
| 60 | \r | |
| 61 | ;\r | |
| 62 | ; Fixup the ebp point to permenent memory\r | |
| 63 | ;\r | |
| 64 | mov eax, ebp\r | |
| 65 | sub eax, ebx\r | |
| 66 | add eax, ecx\r | |
| 67 | mov ebp, eax ; From now, ebp is pointed to permenent memory\r | |
| 68 | \r | |
| 69 | pop edx\r | |
| 70 | pop ecx\r | |
| 71 | pop ebx\r | |
| 72 | pop eax\r | |
| 73 | ret\r | |
| 74 | SecSwitchStack ENDP\r | |
| 75 | \r | |
| 76 | END\r |