/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* * @OSF_COPYRIGHT@ */ /* * Mach Operating System * Copyright (c) 1991,1990 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. */ #include #include #define CR0_PE_ON 0x1 #define CR0_PE_OFF 0xfffffffe .file "slave_boot.s" .text #define LJMP(segment,address) \ .byte 0xea ;\ .long address-EXT(slave_boot_base) ;\ .word segment #define LGDT(address) \ .word 0x010f ;\ .byte 0x15 ;\ .long address-EXT(slave_boot_base) Entry(slave_boot_base) /* code is loaded at 0x0:0x1000 */ /* ljmp to the next instruction to set up %cs */ data16 LJMP(MP_BOOTSEG, EXT(slave_pstart)) Entry(slave_pstart) /* set up %ds */ mov %cs, %ax mov %ax, %ds /* set up %ss and %esp */ data16 mov $(MP_BOOTSEG), %eax mov %ax, %ss data16 mov $(MP_BOOTSTACK), %esp /*set up %es */ mov %ax, %es /* change to protected mode */ data16 call EXT(real_to_prot) push MP_MACH_START call EXT(startprog) /* real_to_prot() transfer from real mode to protected mode. */ Entry(real_to_prot) /* guarantee that interrupt is disabled when in prot mode */ cli /* load the gdtr */ addr16 data16 LGDT(EXT(gdtr)) /* set the PE bit of CR0 */ mov %cr0, %eax data16 or $(CR0_PE_ON), %eax mov %eax, %cr0 /* make intrasegment jump to flush the processor pipeline and */ /* reload CS register */ data16 LJMP(0x08, xprot) xprot: /* we are in USE32 mode now */ /* set up the protective mode segment registers : DS, SS, ES */ mov $0x10, %eax movw %ax, %ds movw %ax, %ss movw %ax, %es ret /* startprog(phyaddr) start the program on protected mode where phyaddr is the entry point */ Entry(startprog) push %ebp mov %esp, %ebp mov 0x8(%ebp), %ecx /* entry offset */ mov $0x28, %ebx /* segment */ push %ebx push %ecx /* set up %ds and %es */ mov $0x20, %ebx movw %bx, %ds movw %bx, %es lret . = MP_GDT-MP_BOOT /* GDT location */ Entry(Gdt) /* 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 | * | | | * ------------------------------------------------------------ */ .word 0,0 /* 0x0 : null */ .byte 0,0,0,0 .word 0xffff,MP_BOOT /* 0x8 : boot code */ .byte 0,0x9e,0x40,0 .word 0xffff,MP_BOOT /* 0x10 : boot data */ .byte 0,0x92,0x40,0 .word 0xffff,MP_BOOT /* 0x18 : boot code, 16 bits */ .byte 0,0x9e,0x0,0 .word 0xffff,0 /* 0x20 : init data */ .byte 0,0x92,0xcf,0 .word 0xffff,0 /* 0x28 : init code */ .byte 0,0x9e,0xcf,0 Entry(gdtr) .short 48 /* limit (8*6 segs) */ .short MP_GDT /* base low */ .short 0 /* base high */ Entry(slave_boot_end)