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/*
* Copyright (c) 1995-1994 The University of Utah and
* the Computer Systems Laboratory at the University of Utah (CSL).
* All rights reserved.
*
* Permission to use, copy, modify and distribute this software is hereby
* granted provided that (1) source code retains these copyright, permission,
* and disclaimer notices, and (2) redistributions including binaries
* reproduce the notices in supporting documentation, and (3) all advertising
* materials mentioning features or use of this software display the following
* acknowledgement: ``This product includes software developed by the
* Computer Systems Laboratory at the University of Utah.''
*
* THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS
* IS" CONDITION. THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF
* ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* CSL requests users of this software to return to csl-dist@cs.utah.edu any
* improvements that they make and grant CSL redistribution rights.
*
* Author: Bryan Ford, University of Utah CSL
*/
#include <mach/machine/code16.h>
#include <mach/machine/seg.h>
#include "vm_param.h"
#include "cpu.h"
CODE16
/* This 16-bit function initializes CPU 0's GDT
just enough to get in and out of protected (and possibly paged) mode,
with all addresses assuming identity-mapped memory. */
void i16_gdt_init_temp()
{
/* Create temporary kernel code and data segment descriptors.
(They'll be reinitialized later after paging is enabled.) */
i16_fill_gdt_descriptor(&cpu[0], KERNEL_CS,
boot_image_pa, 0xffffffff,
ACC_PL_K|ACC_CODE_R, SZ_32);
i16_fill_gdt_descriptor(&cpu[0], KERNEL_DS,
boot_image_pa, 0xffffffff,
ACC_PL_K|ACC_DATA_W, SZ_32);
i16_fill_gdt_descriptor(&cpu[0], KERNEL_16_CS,
boot_image_pa, 0xffff,
ACC_PL_K|ACC_CODE_R, SZ_16);
i16_fill_gdt_descriptor(&cpu[0], KERNEL_16_DS,
boot_image_pa, 0xffff,
ACC_PL_K|ACC_DATA_W, SZ_16);
}
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