1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2014, Neel Natu (neel@freebsd.org)
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 unmodified, this list of conditions, and the following
12 * disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 #include "opt_bhyve_snapshot.h"
31
32 #include <sys/param.h>
33 #include <sys/queue.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/systm.h>
37
38 #include <machine/vmm.h>
39 #include <machine/vmm_snapshot.h>
40
41 #include "vpmtmr.h"
42
43 /*
44 * The ACPI Power Management timer is a free-running 24- or 32-bit
45 * timer with a frequency of 3.579545MHz
46 *
47 * This implementation will be 32-bits
48 */
49
50 #define PMTMR_FREQ 3579545 /* 3.579545MHz */
51
52 struct vpmtmr {
53 sbintime_t freq_sbt;
54 sbintime_t baseuptime;
55 uint32_t baseval;
56 };
57
58 static MALLOC_DEFINE(M_VPMTMR, "vpmtmr", "bhyve virtual acpi timer");
59
60 struct vpmtmr *
vpmtmr_init(struct vm * vm)61 vpmtmr_init(struct vm *vm)
62 {
63 struct vpmtmr *vpmtmr;
64 struct bintime bt;
65
66 vpmtmr = malloc(sizeof(struct vpmtmr), M_VPMTMR, M_WAITOK | M_ZERO);
67 vpmtmr->baseuptime = sbinuptime();
68 vpmtmr->baseval = 0;
69
70 FREQ2BT(PMTMR_FREQ, &bt);
71 vpmtmr->freq_sbt = bttosbt(bt);
72
73 return (vpmtmr);
74 }
75
76 void
vpmtmr_cleanup(struct vpmtmr * vpmtmr)77 vpmtmr_cleanup(struct vpmtmr *vpmtmr)
78 {
79
80 free(vpmtmr, M_VPMTMR);
81 }
82
83 int
vpmtmr_handler(struct vm * vm,bool in,int port,int bytes,uint32_t * val)84 vpmtmr_handler(struct vm *vm, bool in, int port, int bytes, uint32_t *val)
85 {
86 struct vpmtmr *vpmtmr;
87 sbintime_t now, delta;
88
89 if (!in || bytes != 4)
90 return (-1);
91
92 vpmtmr = vm_pmtmr(vm);
93
94 /*
95 * No locking needed because 'baseuptime' and 'baseval' are
96 * written only during initialization.
97 */
98 now = sbinuptime();
99 delta = now - vpmtmr->baseuptime;
100 KASSERT(delta >= 0, ("vpmtmr_handler: uptime went backwards: "
101 "%#lx to %#lx", vpmtmr->baseuptime, now));
102 *val = vpmtmr->baseval + delta / vpmtmr->freq_sbt;
103
104 return (0);
105 }
106
107 #ifdef BHYVE_SNAPSHOT
108 int
vpmtmr_snapshot(struct vpmtmr * vpmtmr,struct vm_snapshot_meta * meta)109 vpmtmr_snapshot(struct vpmtmr *vpmtmr, struct vm_snapshot_meta *meta)
110 {
111 int ret;
112
113 SNAPSHOT_VAR_OR_LEAVE(vpmtmr->baseval, meta, ret, done);
114
115 done:
116 return (ret);
117 }
118 #endif
119