| 1 | /*␊ |
| 2 | * Copyright (c) 1999-2003 Apple Computer, Inc. All rights reserved.␊ |
| 3 | *␊ |
| 4 | * ␊ |
| 5 | * Portions Copyright (c) 1999-2003 Apple Computer, Inc. All Rights␊ |
| 6 | * Reserved. This file contains Original Code and/or Modifications of␊ |
| 7 | * Original Code as defined in and that are subject to the Apple Public␊ |
| 8 | * Source License Version 2.0 (the "License"). You may not use this file␊ |
| 9 | * except in compliance with the License. Please obtain a copy of the␊ |
| 10 | * License at http://www.apple.com/publicsource and read it before using␊ |
| 11 | * this file.␊ |
| 12 | * ␊ |
| 13 | * The Original Code and all software distributed under the License are␊ |
| 14 | * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER␊ |
| 15 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,␊ |
| 16 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,␊ |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT. Please see the␊ |
| 18 | * License for the specific language governing rights and limitations␊ |
| 19 | * under the License.␊ |
| 20 | * ␊ |
| 21 | * ␊ |
| 22 | * Mach Operating System␊ |
| 23 | * Copyright (c) 1990 Carnegie-Mellon University␊ |
| 24 | * Copyright (c) 1989 Carnegie-Mellon University␊ |
| 25 | * All rights reserved. The CMU software License Agreement specifies␊ |
| 26 | * the terms and conditions for use and redistribution.␊ |
| 27 | *␊ |
| 28 | *␊ |
| 29 | * ␉␉␉INTEL CORPORATION PROPRIETARY INFORMATION␊ |
| 30 | *␊ |
| 31 | *␉This software is supplied under the terms of a license agreement or ␊ |
| 32 | *␉nondisclosure agreement with Intel Corporation and may not be copied ␊ |
| 33 | *␉nor disclosed except in accordance with the terms of that agreement.␊ |
| 34 | *␊ |
| 35 | *␉Copyright 1988, 1989 Intel Corporation␊ |
| 36 | *␊ |
| 37 | * Copyright 1993 NeXT, Inc.␊ |
| 38 | * All rights reserved.␊ |
| 39 | */␊ |
| 40 | ␊ |
| 41 | #include "memory.h"␊ |
| 42 | ␊ |
| 43 | /* Segment Descriptor␊ |
| 44 | *␊ |
| 45 | * 31 24 19 16 7 0␊ |
| 46 | * ------------------------------------------------------------␊ |
| 47 | * | | |B| |A| | | |1|0|E|W|A| |␊ |
| 48 | * | BASE 31..24 |G|/|0|V| LIMIT |P|DPL| TYPE | BASE 23:16 |␊ |
| 49 | * | | |D| |L| 19..16| | |1|1|C|R|A| |␊ |
| 50 | * ------------------------------------------------------------␊ |
| 51 | * | | |␊ |
| 52 | * | BASE 15..0 | LIMIT 15..0 |␊ |
| 53 | * | | |␊ |
| 54 | * ------------------------------------------------------------␊ |
| 55 | */␊ |
| 56 | ␊ |
| 57 | struct seg_desc {␊ |
| 58 | unsigned short limit_15_0;␊ |
| 59 | unsigned short base_15_0;␊ |
| 60 | unsigned char base_23_16;␊ |
| 61 | unsigned char bit_15_8;␊ |
| 62 | unsigned char bit_23_16;␊ |
| 63 | unsigned char base_31_24;␊ |
| 64 | };␊ |
| 65 | ␊ |
| 66 | // turbo - GDT must be in first 64k segment␊ |
| 67 | struct seg_desc __attribute__ ((section("__INIT,__data"))) Gdt[ NGDTENT ] = {␊ |
| 68 | /* 0x0 : null */␊ |
| 69 | {0x0000, 0x0000, 0x00, 0x00, 0x00, 0x00},␊ |
| 70 | ␊ |
| 71 | /* 0x8 : boot protected mode 32-bit code segment␊ |
| 72 | byte granularity, 1MB limit, MEMBASE offset */␊ |
| 73 | //{0xFFFF, MEMBASE, 0x00, 0x9E, 0x4F, 0x00}, ␊ |
| 74 | ␉{0xFFFF, 0x0000, 0x00, 0x9E, 0xCF, 0x00},␊ |
| 75 | ␊ |
| 76 | /* 0x10 : boot protected mode data segment␊ |
| 77 | page granularity, 4GB limit, MEMBASE offset */␊ |
| 78 | {0xFFFF, MEMBASE, 0x00, 0x92, 0xCF, 0x00},␊ |
| 79 | ␊ |
| 80 | /* 0x18 : boot protected mode 16-bit code segment␊ |
| 81 | byte granularity, 1MB limit, MEMBASE offset */␊ |
| 82 | {0xFFFF, MEMBASE, 0x00, 0x9E, 0x0F, 0x00},␊ |
| 83 | ␊ |
| 84 | /* 0x20 : kernel init 32-bit data segment␊ |
| 85 | page granularity, 4GB limit, zero offset */␊ |
| 86 | {0xFFFF, 0x0000, 0x00, 0x92, 0xCF, 0x00},␊ |
| 87 | ␊ |
| 88 | /* 0x28 : kernel init 32-bit code segment␊ |
| 89 | page granularity, 4GB limit, zero offset */␊ |
| 90 | {0xFFFF, 0x0000, 0x00, 0x9E, 0xCF, 0x00},␊ |
| 91 | ␊ |
| 92 | /* 0x30 : boot real mode data/stack segment␊ |
| 93 | byte granularity, 64K limit, MEMBASE offset, expand-up */␊ |
| 94 | {0xFFFF, MEMBASE, 0x00, 0x92, 0x00, 0x00}, ␊ |
| 95 | };␊ |
| 96 | |
