1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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__FBSDID("$FreeBSD: stable/11/sys/amd64/vmm/io/vpmtmr.c 336190 2018-07-11 07:19:42Z araujo $");
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
40#include "vpmtmr.h"
41
42/*
43 * The ACPI Power Management timer is a free-running 24- or 32-bit
44 * timer with a frequency of 3.579545MHz
45 *
46 * This implementation will be 32-bits
47 */
48
49#define PMTMR_FREQ	3579545  /* 3.579545MHz */
50
51struct vpmtmr {
52	sbintime_t	freq_sbt;
53	sbintime_t	baseuptime;
54	uint32_t	baseval;
55};
56
57static MALLOC_DEFINE(M_VPMTMR, "vpmtmr", "bhyve virtual acpi timer");
58
59struct vpmtmr *
60vpmtmr_init(struct vm *vm)
61{
62	struct vpmtmr *vpmtmr;
63	struct bintime bt;
64
65	vpmtmr = malloc(sizeof(struct vpmtmr), M_VPMTMR, M_WAITOK | M_ZERO);
66	vpmtmr->baseuptime = sbinuptime();
67	vpmtmr->baseval = 0;
68
69	FREQ2BT(PMTMR_FREQ, &bt);
70	vpmtmr->freq_sbt = bttosbt(bt);
71
72	return (vpmtmr);
73}
74
75void
76vpmtmr_cleanup(struct vpmtmr *vpmtmr)
77{
78
79	free(vpmtmr, M_VPMTMR);
80}
81
82int
83vpmtmr_handler(struct vm *vm, int vcpuid, bool in, int port, int bytes,
84    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