xref: /openbmc/qemu/hw/core/or-irq.c (revision 650d103d)
1 /*
2  * QEMU IRQ/GPIO common code.
3  *
4  * Copyright (c) 2016 Alistair Francis <alistair@alistair23.me>.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "hw/irq.h"
27 #include "hw/or-irq.h"
28 #include "migration/vmstate.h"
29 #include "qemu/module.h"
30 
31 static void or_irq_handler(void *opaque, int n, int level)
32 {
33     qemu_or_irq *s = OR_IRQ(opaque);
34     int or_level = 0;
35     int i;
36 
37     s->levels[n] = level;
38 
39     for (i = 0; i < s->num_lines; i++) {
40         or_level |= s->levels[i];
41     }
42 
43     qemu_set_irq(s->out_irq, or_level);
44 }
45 
46 static void or_irq_reset(DeviceState *dev)
47 {
48     qemu_or_irq *s = OR_IRQ(dev);
49     int i;
50 
51     for (i = 0; i < MAX_OR_LINES; i++) {
52         s->levels[i] = false;
53     }
54 }
55 
56 static void or_irq_realize(DeviceState *dev, Error **errp)
57 {
58     qemu_or_irq *s = OR_IRQ(dev);
59 
60     assert(s->num_lines < MAX_OR_LINES);
61 
62     qdev_init_gpio_in(dev, or_irq_handler, s->num_lines);
63 }
64 
65 static void or_irq_init(Object *obj)
66 {
67     qemu_or_irq *s = OR_IRQ(obj);
68 
69     qdev_init_gpio_out(DEVICE(obj), &s->out_irq, 1);
70 }
71 
72 /* The original version of this device had a fixed 16 entries in its
73  * VMState array; devices with more inputs than this need to
74  * migrate the extra lines via a subsection.
75  * The subsection migrates as much of the levels[] array as is needed
76  * (including repeating the first 16 elements), to avoid the awkwardness
77  * of splitting it in two to meet the requirements of VMSTATE_VARRAY_UINT16.
78  */
79 #define OLD_MAX_OR_LINES 16
80 #if MAX_OR_LINES < OLD_MAX_OR_LINES
81 #error MAX_OR_LINES must be at least 16 for migration compatibility
82 #endif
83 
84 static bool vmstate_extras_needed(void *opaque)
85 {
86     qemu_or_irq *s = OR_IRQ(opaque);
87 
88     return s->num_lines >= OLD_MAX_OR_LINES;
89 }
90 
91 static const VMStateDescription vmstate_or_irq_extras = {
92     .name = "or-irq-extras",
93     .version_id = 1,
94     .minimum_version_id = 1,
95     .needed = vmstate_extras_needed,
96     .fields = (VMStateField[]) {
97         VMSTATE_VARRAY_UINT16_UNSAFE(levels, qemu_or_irq, num_lines, 0,
98                                      vmstate_info_bool, bool),
99         VMSTATE_END_OF_LIST(),
100     },
101 };
102 
103 static const VMStateDescription vmstate_or_irq = {
104     .name = TYPE_OR_IRQ,
105     .version_id = 1,
106     .minimum_version_id = 1,
107     .fields = (VMStateField[]) {
108         VMSTATE_BOOL_SUB_ARRAY(levels, qemu_or_irq, 0, OLD_MAX_OR_LINES),
109         VMSTATE_END_OF_LIST(),
110     },
111     .subsections = (const VMStateDescription*[]) {
112         &vmstate_or_irq_extras,
113         NULL
114     },
115 };
116 
117 static Property or_irq_properties[] = {
118     DEFINE_PROP_UINT16("num-lines", qemu_or_irq, num_lines, 1),
119     DEFINE_PROP_END_OF_LIST(),
120 };
121 
122 static void or_irq_class_init(ObjectClass *klass, void *data)
123 {
124     DeviceClass *dc = DEVICE_CLASS(klass);
125 
126     dc->reset = or_irq_reset;
127     dc->props = or_irq_properties;
128     dc->realize = or_irq_realize;
129     dc->vmsd = &vmstate_or_irq;
130 
131     /* Reason: Needs to be wired up to work, e.g. see stm32f205_soc.c */
132     dc->user_creatable = false;
133 }
134 
135 static const TypeInfo or_irq_type_info = {
136    .name = TYPE_OR_IRQ,
137    .parent = TYPE_DEVICE,
138    .instance_size = sizeof(qemu_or_irq),
139    .instance_init = or_irq_init,
140    .class_init = or_irq_class_init,
141 };
142 
143 static void or_irq_register_types(void)
144 {
145     type_register_static(&or_irq_type_info);
146 }
147 
148 type_init(or_irq_register_types)
149