1/*
2 * TOD (Time Of Day) clock
3 *
4 * Copyright 2018 Red Hat, Inc.
5 * Author(s): David Hildenbrand <david@redhat.com>
6 *
7 * This work is licensed under the terms of the GNU GPL, version 2 or later.
8 * See the COPYING file in the top-level directory.
9 */
10
11#include "qemu/osdep.h"
12#include "hw/s390x/tod.h"
13#include "qapi/error.h"
14#include "qemu/error-report.h"
15#include "qemu/module.h"
16#include "sysemu/kvm.h"
17#include "migration/qemu-file-types.h"
18#include "migration/register.h"
19
20void s390_init_tod(void)
21{
22 Object *obj;
23
24 if (kvm_enabled()) {
25 obj = object_new(TYPE_KVM_S390_TOD);
26 } else {
27 obj = object_new(TYPE_QEMU_S390_TOD);
28 }
29 object_property_add_child(qdev_get_machine(), TYPE_S390_TOD, obj, NULL);
30 object_unref(obj);
31
32 qdev_init_nofail(DEVICE(obj));
33}
34
35S390TODState *s390_get_todstate(void)
36{
37 static S390TODState *ts;
38
39 if (!ts) {
40 ts = S390_TOD(object_resolve_path_type("", TYPE_S390_TOD, NULL));
41 }
42
43 return ts;
44}
45
46#define S390_TOD_CLOCK_VALUE_MISSING 0x00
47#define S390_TOD_CLOCK_VALUE_PRESENT 0x01
48
49static void s390_tod_save(QEMUFile *f, void *opaque)
50{
51 S390TODState *td = opaque;
52 S390TODClass *tdc = S390_TOD_GET_CLASS(td);
53 Error *err = NULL;
54 S390TOD tod;
55
56 tdc->get(td, &tod, &err);
57 if (err) {
58 warn_report_err(err);
59 error_printf("Guest clock will not be migrated "
60 "which could cause the guest to hang.");
61 qemu_put_byte(f, S390_TOD_CLOCK_VALUE_MISSING);
62 return;
63 }
64
65 qemu_put_byte(f, S390_TOD_CLOCK_VALUE_PRESENT);
66 qemu_put_byte(f, tod.high);
67 qemu_put_be64(f, tod.low);
68}
69
70static int s390_tod_load(QEMUFile *f, void *opaque, int version_id)
71{
72 S390TODState *td = opaque;
73 S390TODClass *tdc = S390_TOD_GET_CLASS(td);
74 Error *err = NULL;
75 S390TOD tod;
76
77 if (qemu_get_byte(f) == S390_TOD_CLOCK_VALUE_MISSING) {
78 warn_report("Guest clock was not migrated. This could "
79 "cause the guest to hang.");
80 return 0;
81 }
82
83 tod.high = qemu_get_byte(f);
84 tod.low = qemu_get_be64(f);
85
86 tdc->set(td, &tod, &err);
87 if (err) {
88 error_report_err(err);
89 return -1;
90 }
91 return 0;
92}
93
94static SaveVMHandlers savevm_tod = {
95 .save_state = s390_tod_save,
96 .load_state = s390_tod_load,
97};
98
99static void s390_tod_realize(DeviceState *dev, Error **errp)
100{
101 S390TODState *td = S390_TOD(dev);
102
103 /* Legacy migration interface */
104 register_savevm_live(NULL, "todclock", 0, 1, &savevm_tod, td);
105}
106
107static void s390_tod_class_init(ObjectClass *oc, void *data)
108{
109 DeviceClass *dc = DEVICE_CLASS(oc);
110
111 dc->desc = "TOD (Time Of Day) Clock";
112 dc->realize = s390_tod_realize;
113 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
114
115 /* We only have one TOD clock in the system attached to the machine */
116 dc->user_creatable = false;
117}
118
119static TypeInfo s390_tod_info = {
120 .name = TYPE_S390_TOD,
121 .parent = TYPE_DEVICE,
122 .instance_size = sizeof(S390TODState),
123 .class_init = s390_tod_class_init,
124 .class_size = sizeof(S390TODClass),
125 .abstract = true,
126};
127
128static void register_types(void)
129{
130 type_register_static(&s390_tod_info);
131}
132type_init(register_types);
133