xref: /freebsd/usr.sbin/bhyve/amd64/spinup_ap.c (revision 4f8f43b06ed07e96a250855488cc531799d5b78f)
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/cdefs.h>
30 #include <sys/param.h>
31 #include <sys/types.h>
32 
33 #include <machine/vmm.h>
34 #include <vmmapi.h>
35 
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <assert.h>
39 
40 #include "bhyverun.h"
41 #include "spinup_ap.h"
42 
43 static void
44 spinup_ap_realmode(struct vcpu *newcpu, uint64_t rip)
45 {
46 	int vector, error;
47 	uint16_t cs;
48 	uint64_t desc_base;
49 	uint32_t desc_limit, desc_access;
50 
51 	vector = rip >> PAGE_SHIFT;
52 
53 	/*
54 	 * Update the %cs and %rip of the guest so that it starts
55 	 * executing real mode code at at 'vector << 12'.
56 	 */
57 	error = vm_set_register(newcpu, VM_REG_GUEST_RIP, 0);
58 	assert(error == 0);
59 
60 	error = vm_get_desc(newcpu, VM_REG_GUEST_CS, &desc_base,
61 			    &desc_limit, &desc_access);
62 	assert(error == 0);
63 
64 	desc_base = vector << PAGE_SHIFT;
65 	error = vm_set_desc(newcpu, VM_REG_GUEST_CS,
66 			    desc_base, desc_limit, desc_access);
67 	assert(error == 0);
68 
69 	cs = (vector << PAGE_SHIFT) >> 4;
70 	error = vm_set_register(newcpu, VM_REG_GUEST_CS, cs);
71 	assert(error == 0);
72 }
73 
74 void
75 spinup_ap(struct vcpu *newcpu, uint64_t rip)
76 {
77 	int error;
78 
79 	error = vcpu_reset(newcpu);
80 	assert(error == 0);
81 
82 	spinup_ap_realmode(newcpu, rip);
83 
84 	vm_resume_cpu(newcpu);
85 }
86