projects / apple / boot.git / blame
| Commit | Line | Data |
|---|---|---|
| 14c7c974 A |
1 | /* |
| 2 | * Copyright (c) 1999 Apple Computer, Inc. All rights reserved. | |
| 3 | * | |
| 4 | * @APPLE_LICENSE_HEADER_START@ | |
| 5 | * | |
| 4f6e3300 A |
6 | * Portions Copyright (c) 1999 Apple Computer, Inc. All Rights |
| 7 | * Reserved. This file contains Original Code and/or Modifications of | |
| 8 | * Original Code as defined in and that are subject to the Apple Public | |
| 9 | * Source License Version 1.1 (the "License"). You may not use this file | |
| 10 | * except in compliance with the License. Please obtain a copy of the | |
| 11 | * License at http://www.apple.com/publicsource and read it before using | |
| 12 | * this file. | |
| 14c7c974 A |
13 | * |
| 14 | * The Original Code and all software distributed under the License are | |
| 4f6e3300 | 15 | * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
| 14c7c974 A |
16 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
| 17 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 4f6e3300 A |
18 | * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT. Please see the |
| 19 | * License for the specific language governing rights and limitations | |
| 20 | * under the License. | |
| 14c7c974 A |
21 | * |
| 22 | * @APPLE_LICENSE_HEADER_END@ | |
| 23 | */ | |
| 24 | /* | |
| 25 | * Mach Operating System | |
| 26 | * Copyright (c) 1990 Carnegie-Mellon University | |
| 27 | * Copyright (c) 1989 Carnegie-Mellon University | |
| 28 | * All rights reserved. The CMU software License Agreement specifies | |
| 29 | * the terms and conditions for use and redistribution. | |
| 30 | */ | |
| 31 | ||
| 32 | /* | |
| 33 | * INTEL CORPORATION PROPRIETARY INFORMATION | |
| 34 | * | |
| 35 | * This software is supplied under the terms of a license agreement or | |
| 36 | * nondisclosure agreement with Intel Corporation and may not be copied | |
| 37 | * nor disclosed except in accordance with the terms of that agreement. | |
| 38 | * | |
| 39 | * Copyright 1988, 1989 Intel Corporation | |
| 40 | */ | |
| 41 | ||
| 42 | /* | |
| 43 | * Copyright 1993 NeXT, Inc. | |
| 44 | * All rights reserved. | |
| 45 | */ | |
| 46 | ||
| 47 | #include "memory.h" | |
| 48 | ||
| 49 | #define NGDTENT 6 | |
| 50 | #define GDTLIMIT 48 /* NGDTENT * 8 */ | |
| 51 | ||
| 52 | /* Segment Descriptor | |
| 53 | * | |
| 54 | * 31 24 19 16 7 0 | |
| 55 | * ------------------------------------------------------------ | |
| 56 | * | | |B| |A| | | |1|0|E|W|A| | | |
| 57 | * | BASE 31..24 |G|/|0|V| LIMIT |P|DPL| TYPE | BASE 23:16 | | |
| 58 | * | | |D| |L| 19..16| | |1|1|C|R|A| | | |
| 59 | * ------------------------------------------------------------ | |
| 60 | * | | | | |
| 61 | * | BASE 15..0 | LIMIT 15..0 | | |
| 62 | * | | | | |
| 63 | * ------------------------------------------------------------ | |
| 64 | */ | |
| 65 | ||
| 66 | struct seg_desc { | |
| 67 | unsigned short limit_15_0; | |
| 68 | unsigned short base_15_0; | |
| 69 | unsigned char base_23_16; | |
| 70 | unsigned char bit_15_8; | |
| 71 | unsigned char bit_23_16; | |
| 72 | unsigned char base_31_24; | |
| 73 | }; | |
| 74 | ||
| 75 | ||
| 76 | struct seg_desc Gdt[NGDTENT] = { | |
| 77 | {0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, /* 0x0 : null */ | |
| 78 | // byte granularity, 1Mb limit, MEMBASE offset | |
| 79 | {0xFFFF, MEMBASE, 0x0, 0x9E, 0x4F, 0x0}, /* 0x8 : boot code */ | |
| 80 | // dword granularity, 2Gb limit, MEMBASE offset | |
| 81 | {0xFFFF, MEMBASE, 0x0, 0x92, 0xCF, 0x0}, /* 0x10 : boot data */ | |
| 82 | {0xFFFF, MEMBASE, 0x0, 0x9E, 0xF, 0x0}, /* 0x18 : boot code, 16 bits */ | |
| 83 | {0xFFFF, 0x0, 0x0, 0x92, 0xCF, 0x0}, /* 0x20 : init data */ | |
| 84 | {0xFFFF, 0x0, 0x0, 0x9E, 0xCF, 0x0} /* 0x28 : init code */ | |
| 85 | }; | |
| 86 |