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/* $NetBSD: table.c,v 1.6 1994/10/27 04:14:42 cgd Exp $ */
/*
* Ported to boot 386BSD by Julian Elischer (julian@tfs.com) Sept 1992
*
* Mach Operating System
* Copyright (c) 1992, 1991 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
Copyright 1988, 1989, 1990, 1991, 1992
by Intel Corporation, Santa Clara, California.
All Rights Reserved
Permission to use, copy, modify, and distribute this software and
its documentation for any purpose and without fee is hereby
granted, provided that the above copyright notice appears in all
copies and that both the copyright notice and this permission notice
appear in supporting documentation, and that the name of Intel
not be used in advertising or publicity pertaining to distribution
of the software without specific, written prior permission.
INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* Segment Descriptor
*
* 31 24 19 16 7 0
* ------------------------------------------------------------
* | | |B| |A| | | |1|0|E|W|A| |
* | BASE 31..24 |G|/|0|V| LIMIT |P|DPL| TYPE | BASE 23:16 |
* | | |D| |L| 19..16| | |1|1|C|R|A| |
* ------------------------------------------------------------
* | | |
* | BASE 15..0 | LIMIT 15..0 |
* | | |
* ------------------------------------------------------------
*/
struct seg_desc {
unsigned short limit_15_0;
unsigned short base_15_0;
unsigned char base_23_16;
unsigned char p_dpl_type;
unsigned char g_b_a_limit;
unsigned char base_31_24;
};
#define RUN 0 /* not really 0, but filled in at boot time */
struct seg_desc Gdt[] = {
{0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, /* 0x0 : null */
{0xFFFF, 0x0, 0x0, 0x9F, 0xCF, 0x0}, /* 0x08 : kernel code */
/* 0x9E? */
{0xFFFF, 0x0, 0x0, 0x93, 0xCF, 0x0}, /* 0x10 : kernel data */
/* 0x92? */
{0xFFFF, RUN, RUN, 0x9E, 0xCF, 0x0}, /* 0x18 : boot code */
{0xFFFF, RUN, RUN, 0x92, 0xCF, 0x0}, /* 0x20 : boot data */
{0xFFFF, RUN, RUN, 0x9E, 0x0, 0x0}, /* 0x28 : boot code, 16 bits */
};
struct pseudo_desc {
unsigned short limit;
unsigned short base_low;
unsigned short base_high;
};
struct pseudo_desc Gdtr = { sizeof Gdt - 1, RUN, RUN };
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