FreeBSD/Linux Kernel Cross Reference
sys/i386/xen/xen_rtc.c
1 /*-
2 * Copyright (c) 2009 Adrian Chadd
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 #include <sys/clock.h>
36 #include <sys/lock.h>
37 #include <sys/mutex.h>
38 #include <sys/kernel.h>
39 #include <sys/module.h>
40 #include <sys/time.h>
41
42 #include <xen/xen_intr.h>
43 #include <vm/vm.h>
44 #include <vm/pmap.h>
45 #include <machine/pmap.h>
46 #include <xen/hypervisor.h>
47 #include <machine/xen/xen-os.h>
48 #include <machine/xen/xenfunc.h>
49 #include <xen/interface/io/xenbus.h>
50 #include <xen/interface/vcpu.h>
51 #include <machine/cpu.h>
52
53 #include <machine/xen/xen_clock_util.h>
54
55 #include "clock_if.h"
56
57 static int
58 xen_rtc_probe(device_t dev)
59 {
60 device_set_desc(dev, "Xen Hypervisor Clock");
61 printf("[XEN] xen_rtc_probe: probing Hypervisor RTC clock\n");
62 if (! HYPERVISOR_shared_info) {
63 device_printf(dev, "No hypervisor shared page found; RTC can not start.\n");
64 return (EINVAL);
65 }
66 return (0);
67 }
68
69 static int
70 xen_rtc_attach(device_t dev)
71 {
72 printf("[XEN] xen_rtc_attach: attaching Hypervisor RTC clock\n");
73 clock_register(dev, 1000000);
74 return(0);
75 }
76
77 static int
78 xen_rtc_settime(device_t dev __unused, struct timespec *ts)
79 {
80 device_printf(dev, "[XEN] xen_rtc_settime\n");
81 /*
82 * Don't return EINVAL here; just silently fail if the domain isn't privileged enough
83 * to set the TOD.
84 */
85 return(0);
86 }
87
88 /*
89 * The Xen time structures document the hypervisor start time and the
90 * uptime-since-hypervisor-start (in nsec.) They need to be combined
91 * in order to calculate a TOD clock.
92 */
93 static int
94 xen_rtc_gettime(device_t dev, struct timespec *ts)
95 {
96 struct timespec w_ts, u_ts;
97
98 device_printf(dev, "[XEN] xen_rtc_gettime\n");
99 xen_fetch_wallclock(&w_ts);
100 device_printf(dev, "[XEN] xen_rtc_gettime: wallclock %ld sec; %ld nsec\n", (long int) w_ts.tv_sec, (long int) w_ts.tv_nsec);
101 xen_fetch_uptime(&u_ts);
102 device_printf(dev, "[XEN] xen_rtc_gettime: uptime %ld sec; %ld nsec\n", (long int) u_ts.tv_sec, (long int) u_ts.tv_nsec);
103
104 timespecclear(ts);
105 timespecadd(ts, &w_ts);
106 timespecadd(ts, &u_ts);
107
108 device_printf(dev, "[XEN] xen_rtc_gettime: TOD %ld sec; %ld nsec\n", (long int) ts->tv_sec, (long int) ts->tv_nsec);
109
110 return(0);
111 }
112
113 static void
114 xen_rtc_identify(driver_t *drv, device_t parent)
115 {
116 BUS_ADD_CHILD(parent, 0, "rtc", 0);
117 }
118
119 static device_method_t xen_rtc_methods[] = {
120 /* Device interface */
121 DEVMETHOD(device_probe, xen_rtc_probe),
122 DEVMETHOD(device_attach, xen_rtc_attach),
123 DEVMETHOD(device_identify, xen_rtc_identify),
124
125 DEVMETHOD(device_detach, bus_generic_detach),
126 DEVMETHOD(device_shutdown, bus_generic_shutdown),
127
128 /* clock interface */
129 DEVMETHOD(clock_gettime, xen_rtc_gettime),
130 DEVMETHOD(clock_settime, xen_rtc_settime),
131
132 { 0, 0 }
133 };
134
135
136 static driver_t xen_rtc_driver = {
137 "rtc",
138 xen_rtc_methods,
139 0
140 };
141
142 static devclass_t xen_rtc_devclass;
143
144 DRIVER_MODULE(rtc, nexus, xen_rtc_driver, xen_rtc_devclass, 0, 0);
Cache object: 125f43f7c7b6af7d21d8df0716f38540
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