projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| b295fbba LG |
1 | ;; @file\r |
| 2 | ; This is the code that goes from real-mode to protected mode.\r | |
| 3 | ; It consumes the reset vector, configures the stack.\r | |
| 4 | ;\r | |
| e37bb20c | 5 | ; Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>\r |
| b295fbba LG |
6 | ; This program and the accompanying materials\r |
| 7 | ; are licensed and made available under the terms and conditions of the BSD License\r | |
| 8 | ; which accompanies this distribution. The full text of the license may be found at\r | |
| 9 | ; http://opensource.org/licenses/bsd-license.php.\r | |
| 10 | ;\r | |
| 11 | ; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
| 12 | ; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
| 13 | ;;\r | |
| 14 | \r | |
| 15 | ;\r | |
| 16 | ; Define assembler characteristics\r | |
| 17 | ;\r | |
| 18 | \r | |
| 19 | extern ASM_PFX(TempRamInitApi)\r | |
| 20 | \r | |
| 21 | SECTION .text\r | |
| 22 | \r | |
| 23 | %macro RET_ESI 0\r | |
| 24 | \r | |
| 25 | movd esi, mm7 ; restore ESP from MM7\r | |
| 26 | jmp esi\r | |
| 27 | \r | |
| 28 | %endmacro\r | |
| 29 | \r | |
| 30 | ;\r | |
| 31 | ; Perform early platform initialization\r | |
| 32 | ;\r | |
| 33 | global ASM_PFX(SecPlatformInit)\r | |
| 34 | ASM_PFX(SecPlatformInit):\r | |
| 35 | \r | |
| 36 | RET_ESI\r | |
| 37 | \r | |
| 38 | ;\r | |
| 39 | ; Protected mode portion initializes stack, configures cache, and calls C entry point\r | |
| 40 | ;\r | |
| 41 | \r | |
| 42 | ;----------------------------------------------------------------------------\r | |
| 43 | ;\r | |
| 44 | ; Procedure: ProtectedModeEntryPoint\r | |
| 45 | ;\r | |
| 46 | ; Input: Executing in 32 Bit Protected (flat) mode\r | |
| 47 | ; cs: 0-4GB\r | |
| 48 | ; ds: 0-4GB\r | |
| 49 | ; es: 0-4GB\r | |
| 50 | ; fs: 0-4GB\r | |
| 51 | ; gs: 0-4GB\r | |
| 52 | ; ss: 0-4GB\r | |
| 53 | ;\r | |
| 54 | ; Output: This function never returns\r | |
| 55 | ;\r | |
| 56 | ; Destroys:\r | |
| 57 | ; ecx\r | |
| 58 | ; edi\r | |
| 59 | ; esi\r | |
| 60 | ; esp\r | |
| 61 | ;\r | |
| 62 | ; Description:\r | |
| 63 | ; Perform any essential early platform initilaisation\r | |
| 64 | ; Setup a stack\r | |
| 65 | ;\r | |
| 66 | ;----------------------------------------------------------------------------\r | |
| 67 | global ASM_PFX(ProtectedModeEntryPoint)\r | |
| 68 | ASM_PFX(ProtectedModeEntryPoint):\r | |
| 69 | ;\r | |
| 70 | ; Dummy function. Consume 2 API to make sure they can be linked.\r | |
| 71 | ;\r | |
| 72 | mov eax, ASM_PFX(TempRamInitApi)\r | |
| 73 | \r | |
| 74 | ; Should never return\r | |
| 75 | jmp $\r | |
| 76 | \r | |
| 77 | ;\r | |
| 78 | ; ROM-based Global-Descriptor Table for the PEI Phase\r | |
| 79 | ;\r | |
| 80 | align 16\r | |
| 81 | global ASM_PFX(BootGdtTable)\r | |
| 82 | \r | |
| 83 | ;\r | |
| 84 | ; GDT[0]: 0x00: Null entry, never used.\r | |
| 85 | ;\r | |
| 86 | NULL_SEL equ $ - GDT_BASE ; Selector [0]\r | |
| 87 | GDT_BASE:\r | |
| 88 | ASM_PFX(BootGdtTable): DD 0\r | |
| 89 | DD 0\r | |
| 90 | ;\r | |
| 91 | ; Linear code segment descriptor\r | |
| 92 | ;\r | |
| 93 | LINEAR_CODE_SEL equ $ - GDT_BASE ; Selector [0x8]\r | |
| 94 | DW 0FFFFh ; limit 0xFFFF\r | |
| 95 | DW 0 ; base 0\r | |
| 96 | DB 0\r | |
| 97 | DB 09Bh ; present, ring 0, data, expand-up, not-writable\r | |
| 98 | DB 0CFh ; page-granular, 32-bit\r | |
| 99 | DB 0\r | |
| 100 | ;\r | |
| 101 | ; System data segment descriptor\r | |
| 102 | ;\r | |
| 103 | SYS_DATA_SEL equ $ - GDT_BASE ; Selector [0x10]\r | |
| 104 | DW 0FFFFh ; limit 0xFFFF\r | |
| 105 | DW 0 ; base 0\r | |
| 106 | DB 0\r | |
| 107 | DB 093h ; present, ring 0, data, expand-up, not-writable\r | |
| 108 | DB 0CFh ; page-granular, 32-bit\r | |
| 109 | DB 0\r | |
| 110 | \r | |
| 111 | GDT_SIZE EQU $ - GDT_BASE ; Size, in bytes\r | |
| 112 | \r | |
| 113 | ;\r | |
| 114 | ; GDT Descriptor\r | |
| 115 | ;\r | |
| 116 | GdtDesc: ; GDT descriptor\r | |
| 117 | DW GDT_SIZE - 1 ; GDT limit\r | |
| 118 | DD GDT_BASE ; GDT base address\r | |
| 119 | \r | |
| 120 | global ASM_PFX(ProtectedModeEntryLinearAddress)\r | |
| 121 | global ASM_PFX(ProtectedModeEntryLinearOffset)\r | |
| 122 | \r | |
| 123 | ASM_PFX(ProtectedModeEntryLinearAddress):\r | |
| 124 | ASM_PFX(ProtectedModeEntryLinearOffset):\r | |
| 125 | DD ASM_PFX(ProtectedModeEntryPoint) ; Offset of our 32 bit code\r | |
| 126 | DW LINEAR_CODE_SEL\r | |
| e37bb20c | 127 | \r |