xref: /openbmc/qemu/hw/core/reset.c (revision 5f69e42d)
1 /*
2  *  Reset handlers.
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  * Copyright (c) 2016 Red Hat, Inc.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "sysemu/reset.h"
28 #include "hw/resettable.h"
29 #include "hw/core/resetcontainer.h"
30 
31 /*
32  * Return a pointer to the singleton container that holds all the Resettable
33  * items that will be reset when qemu_devices_reset() is called.
34  */
35 static ResettableContainer *get_root_reset_container(void)
36 {
37     static ResettableContainer *root_reset_container;
38 
39     if (!root_reset_container) {
40         root_reset_container =
41             RESETTABLE_CONTAINER(object_new(TYPE_RESETTABLE_CONTAINER));
42     }
43     return root_reset_container;
44 }
45 
46 /*
47  * This is an Object which implements Resettable simply to call the
48  * callback function in the hold phase.
49  */
50 #define TYPE_LEGACY_RESET "legacy-reset"
51 OBJECT_DECLARE_SIMPLE_TYPE(LegacyReset, LEGACY_RESET)
52 
53 struct LegacyReset {
54     Object parent;
55     ResettableState reset_state;
56     QEMUResetHandler *func;
57     void *opaque;
58     bool skip_on_snapshot_load;
59 };
60 
61 OBJECT_DEFINE_SIMPLE_TYPE_WITH_INTERFACES(LegacyReset, legacy_reset, LEGACY_RESET, OBJECT, { TYPE_RESETTABLE_INTERFACE }, { })
62 
63 static ResettableState *legacy_reset_get_state(Object *obj)
64 {
65     LegacyReset *lr = LEGACY_RESET(obj);
66     return &lr->reset_state;
67 }
68 
69 static void legacy_reset_hold(Object *obj, ResetType type)
70 {
71     LegacyReset *lr = LEGACY_RESET(obj);
72 
73     if (type == RESET_TYPE_SNAPSHOT_LOAD && lr->skip_on_snapshot_load) {
74         return;
75     }
76     lr->func(lr->opaque);
77 }
78 
79 static void legacy_reset_init(Object *obj)
80 {
81 }
82 
83 static void legacy_reset_finalize(Object *obj)
84 {
85 }
86 
87 static void legacy_reset_class_init(ObjectClass *klass, void *data)
88 {
89     ResettableClass *rc = RESETTABLE_CLASS(klass);
90 
91     rc->get_state = legacy_reset_get_state;
92     rc->phases.hold = legacy_reset_hold;
93 }
94 
95 void qemu_register_reset(QEMUResetHandler *func, void *opaque)
96 {
97     Object *obj = object_new(TYPE_LEGACY_RESET);
98     LegacyReset *lr = LEGACY_RESET(obj);
99 
100     lr->func = func;
101     lr->opaque = opaque;
102     qemu_register_resettable(obj);
103 }
104 
105 void qemu_register_reset_nosnapshotload(QEMUResetHandler *func, void *opaque)
106 {
107     Object *obj = object_new(TYPE_LEGACY_RESET);
108     LegacyReset *lr = LEGACY_RESET(obj);
109 
110     lr->func = func;
111     lr->opaque = opaque;
112     lr->skip_on_snapshot_load = true;
113     qemu_register_resettable(obj);
114 }
115 
116 typedef struct FindLegacyInfo {
117     QEMUResetHandler *func;
118     void *opaque;
119     LegacyReset *lr;
120 } FindLegacyInfo;
121 
122 static void find_legacy_reset_cb(Object *obj, void *opaque, ResetType type)
123 {
124     LegacyReset *lr;
125     FindLegacyInfo *fli = opaque;
126 
127     /* Not everything in the ResettableContainer will be a LegacyReset */
128     lr = LEGACY_RESET(object_dynamic_cast(obj, TYPE_LEGACY_RESET));
129     if (lr && lr->func == fli->func && lr->opaque == fli->opaque) {
130         fli->lr = lr;
131     }
132 }
133 
134 static LegacyReset *find_legacy_reset(QEMUResetHandler *func, void *opaque)
135 {
136     /*
137      * Find the LegacyReset with the specified func and opaque,
138      * by getting the ResettableContainer to call our callback for
139      * every item in it.
140      */
141     ResettableContainer *rootcon = get_root_reset_container();
142     ResettableClass *rc = RESETTABLE_GET_CLASS(rootcon);
143     FindLegacyInfo fli;
144 
145     fli.func = func;
146     fli.opaque = opaque;
147     fli.lr = NULL;
148     rc->child_foreach(OBJECT(rootcon), find_legacy_reset_cb,
149                       &fli, RESET_TYPE_COLD);
150     return fli.lr;
151 }
152 
153 void qemu_unregister_reset(QEMUResetHandler *func, void *opaque)
154 {
155     Object *obj = OBJECT(find_legacy_reset(func, opaque));
156 
157     if (obj) {
158         qemu_unregister_resettable(obj);
159         object_unref(obj);
160     }
161 }
162 
163 void qemu_register_resettable(Object *obj)
164 {
165     resettable_container_add(get_root_reset_container(), obj);
166 }
167 
168 void qemu_unregister_resettable(Object *obj)
169 {
170     resettable_container_remove(get_root_reset_container(), obj);
171 }
172 
173 void qemu_devices_reset(ShutdownCause reason)
174 {
175     ResetType type = (reason == SHUTDOWN_CAUSE_SNAPSHOT_LOAD) ?
176         RESET_TYPE_SNAPSHOT_LOAD : RESET_TYPE_COLD;
177 
178     /* Reset the simulation */
179     resettable_reset(OBJECT(get_root_reset_container()), type);
180 }
181