xref: /openbsd/sys/arch/amd64/amd64/gdt.c (revision b767b017)
1 /*	$OpenBSD: gdt.c,v 1.26 2018/02/21 19:24:15 guenther Exp $	*/
2 /*	$NetBSD: gdt.c,v 1.1 2003/04/26 18:39:28 fvdl Exp $	*/
3 
4 /*-
5  * Copyright (c) 1996, 1997 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by John T. Kohl and Charles M. Hannum.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/mutex.h>
36 
37 #include <uvm/uvm_extern.h>
38 
39 #include <machine/tss.h>
40 #include <machine/pcb.h>
41 
42 /*
43  * Load appropriate gdt descriptor; we better be running on *ci
44  */
45 void
gdt_init_cpu(struct cpu_info * ci)46 gdt_init_cpu(struct cpu_info *ci)
47 {
48 	struct region_descriptor region;
49 
50 	set_sys_segment(GDT_ADDR_SYS(ci->ci_gdt, GPROC0_SEL), ci->ci_tss,
51 	    sizeof (struct x86_64_tss)-1, SDT_SYS386TSS, SEL_KPL, 0);
52 
53 	setregion(&region, ci->ci_gdt, GDT_SIZE - 1);
54 	lgdt(&region);
55 	ltr(GSYSSEL(GPROC0_SEL, SEL_KPL));
56 }
57