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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/proc_reg.h>
#include "vm_param.h"
/* Code segment we originally had when we started in real mode. */
unsigned short real_cs;
/* Virtual address of physical memory. */
vm_offset_t phys_mem_va;
/* Physical address of start of boot image. */
vm_offset_t boot_image_pa;
/* Upper limit of known physical memory. */
vm_offset_t phys_mem_max;
CODE16
#include "i16_bios.h"
/* Called by i16_crt0 (or the equivalent)
to set up our basic 16-bit runtime environment
before calling i16_main(). */
void i16_init(void)
{
/* Find our code/data/everything segment. */
real_cs = get_cs();
/* Find out where in physical memory we got loaded. */
boot_image_pa = real_cs << 4;
/* Find out where the bottom of physical memory is.
(We won't be able to directly use it for 32-bit accesses
until we actually get into 32-bit mode.) */
phys_mem_va = -boot_image_pa;
/* The base of linear memory is at the same place,
at least until we turn paging on. */
linear_base_va = phys_mem_va;
}
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