startprog.S revision 1.1.1.1
1 /* $NetBSD: startprog.S,v 1.1.1.1 1997/03/14 02:40:33 perry Exp $ */ 2 3 /* starts program in protected mode / flat space 4 with given stackframe 5 needs global variables flatcodeseg and flatdataseg 6 (gdt offsets) 7 derivied from: NetBSD:sys/arch/i386/boot/asm.S 8 */ 9 10 /* 11 * Ported to boot 386BSD by Julian Elischer (julian (at) tfs.com) Sept 1992 12 * 13 * Mach Operating System 14 * Copyright (c) 1992, 1991 Carnegie Mellon University 15 * All Rights Reserved. 16 * 17 * Permission to use, copy, modify and distribute this software and its 18 * documentation is hereby granted, provided that both the copyright 19 * notice and this permission notice appear in all copies of the 20 * software, derivative works or modified versions, and any portions 21 * thereof, and that both notices appear in supporting documentation. 22 * 23 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 24 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 25 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 26 * 27 * Carnegie Mellon requests users of this software to return to 28 * 29 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU 30 * School of Computer Science 31 * Carnegie Mellon University 32 * Pittsburgh PA 15213-3890 33 * 34 * any improvements or extensions that they make and grant Carnegie Mellon 35 * the rights to redistribute these changes. 36 */ 37 38 /* 39 Copyright 1988, 1989, 1990, 1991, 1992 40 by Intel Corporation, Santa Clara, California. 41 42 All Rights Reserved 43 44 Permission to use, copy, modify, and distribute this software and 45 its documentation for any purpose and without fee is hereby 46 granted, provided that the above copyright notice appears in all 47 copies and that both the copyright notice and this permission notice 48 appear in supporting documentation, and that the name of Intel 49 not be used in advertising or publicity pertaining to distribution 50 of the software without specific, written prior permission. 51 52 INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE 53 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, 54 IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR 55 CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 56 LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT, 57 NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 58 WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 59 */ 60 61 #include <machine/asm.h> 62 63 /* 64 * startprog(phyaddr,argc,argv,stack) 65 * start the program on protected mode where phyaddr is the entry point 66 */ 67 ENTRY(startprog) 68 pushl %ebp 69 movl %esp, %ebp 70 71 # prepare a new stack 72 movl $flatdataseg, %ebx 73 movw %bx, %es # for arg copy 74 movl 20(%ebp), %eax # stack 75 subl $4,%eax 76 movl %eax, %edi 77 78 # push some number of args onto the stack 79 movl 12(%ebp), %ecx # argc 80 81 movl %ecx, %eax 82 decl %eax 83 shl $2, %eax 84 addl 16(%ebp), %eax # ptr to last arg 85 movl %eax, %esi 86 87 std # backwards 88 rep 89 movsl 90 91 cld # LynxOS depends on it 92 93 movl 8(%ebp), %ecx # entry 94 95 # set new stackptr (movsl decd sp 1 more -> dummy return address) 96 movw %bx, %ss 97 movl %edi, %esp 98 99 # push on our entry address 100 movl $flatcodeseg, %ebx # segment 101 pushl %ebx 102 pushl %ecx #entry 103 104 # convert over the other data segs 105 movl $flatdataseg, %ebx 106 movl %bx, %ds 107 movl %bx, %es 108 109 # convert the PC (and code seg) 110 lret 111
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