xref: /freebsd/usr.sbin/bhyve/amd64/spinup_ap.c (revision 1631382cf2820245cc72965498ff174bb548dd63)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2012 NetApp, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/types.h>
31 
32 #include <machine/vmm.h>
33 #include <vmmapi.h>
34 
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <assert.h>
38 
39 #include "bhyverun.h"
40 #include "spinup_ap.h"
41 
42 static void
43 spinup_ap_realmode(struct vcpu *newcpu, uint64_t rip)
44 {
45 	int vector, error;
46 	uint16_t cs;
47 	uint64_t desc_base;
48 	uint32_t desc_limit, desc_access;
49 
50 	vector = rip >> PAGE_SHIFT;
51 
52 	/*
53 	 * Update the %cs and %rip of the guest so that it starts
54 	 * executing real mode code at at 'vector << 12'.
55 	 */
56 	error = vm_set_register(newcpu, VM_REG_GUEST_RIP, 0);
57 	assert(error == 0);
58 
59 	error = vm_get_desc(newcpu, VM_REG_GUEST_CS, &desc_base,
60 			    &desc_limit, &desc_access);
61 	assert(error == 0);
62 
63 	desc_base = vector << PAGE_SHIFT;
64 	error = vm_set_desc(newcpu, VM_REG_GUEST_CS,
65 			    desc_base, desc_limit, desc_access);
66 	assert(error == 0);
67 
68 	cs = (vector << PAGE_SHIFT) >> 4;
69 	error = vm_set_register(newcpu, VM_REG_GUEST_CS, cs);
70 	assert(error == 0);
71 }
72 
73 void
74 spinup_ap(struct vcpu *newcpu, uint64_t rip)
75 {
76 	int error;
77 
78 	error = vcpu_reset(newcpu);
79 	assert(error == 0);
80 
81 	spinup_ap_realmode(newcpu, rip);
82 
83 	vm_resume_cpu(newcpu);
84 }
85