2 * Copyright (c) 2003 Peter Wemm <peter@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/sys/boot/i386/libi386/amd64_tramp.S,v 1.2 2003/05/17 00:30:51 peter Exp $
27 * $DragonFly: src/sys/boot/pc32/libi386/amd64_tramp.S,v 1.3 2004/07/19 23:30:37 dillon Exp $
30 #include "../bootasm.h"
33 * Quick and dirty trampoline to get into 64 bit (long) mode and running
34 * with paging enabled so that we enter the kernel at its linked address.
36 #define MSR_EFER 0xc0000080
37 #define EFER_LME 0x00000100
38 #define CR4_PAE 0x00000020
39 #define CR4_PSE 0x00000010
40 #define CR0_PG 0x80000000
42 /* GRRR. Deal with BTX that links us for a non-zero location */
43 #define VTOP(x) ((x) + MEM_BTX_USR)
65 .long 0 # null descriptor
67 .long 0x00000000 # %cs
69 .long 0x00000000 # %ds
78 /* Be sure that interrupts are disabled */
81 /* Turn on EFER.LME */
89 orl $(CR4_PAE | CR4_PSE), %eax
92 /* Set %cr3 for PT4 */
96 /* Turn on paging (implicitly sets EFER.LMA) */
101 /* Now we're in compatibility mode. set %cs for long mode */
102 movl $VTOP(gdtdesc), %eax
103 movl VTOP(entry_hi), %esi
104 movl VTOP(entry_lo), %edi
106 ljmp $0x8, $VTOP(longmode)
110 /* We're still running V=P, jump to entry point */