xref: /openbmc/qemu/hw/core/or-irq.c (revision 6a0acfff)
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 "qemu/module.h"
29 
30 static void or_irq_handler(void *opaque, int n, int level)
31 {
32     qemu_or_irq *s = OR_IRQ(opaque);
33     int or_level = 0;
34     int i;
35 
36     s->levels[n] = level;
37 
38     for (i = 0; i < s->num_lines; i++) {
39         or_level |= s->levels[i];
40     }
41 
42     qemu_set_irq(s->out_irq, or_level);
43 }
44 
45 static void or_irq_reset(DeviceState *dev)
46 {
47     qemu_or_irq *s = OR_IRQ(dev);
48     int i;
49 
50     for (i = 0; i < MAX_OR_LINES; i++) {
51         s->levels[i] = false;
52     }
53 }
54 
55 static void or_irq_realize(DeviceState *dev, Error **errp)
56 {
57     qemu_or_irq *s = OR_IRQ(dev);
58 
59     assert(s->num_lines < MAX_OR_LINES);
60 
61     qdev_init_gpio_in(dev, or_irq_handler, s->num_lines);
62 }
63 
64 static void or_irq_init(Object *obj)
65 {
66     qemu_or_irq *s = OR_IRQ(obj);
67 
68     qdev_init_gpio_out(DEVICE(obj), &s->out_irq, 1);
69 }
70 
71 /* The original version of this device had a fixed 16 entries in its
72  * VMState array; devices with more inputs than this need to
73  * migrate the extra lines via a subsection.
74  * The subsection migrates as much of the levels[] array as is needed
75  * (including repeating the first 16 elements), to avoid the awkwardness
76  * of splitting it in two to meet the requirements of VMSTATE_VARRAY_UINT16.
77  */
78 #define OLD_MAX_OR_LINES 16
79 #if MAX_OR_LINES < OLD_MAX_OR_LINES
80 #error MAX_OR_LINES must be at least 16 for migration compatibility
81 #endif
82 
83 static bool vmstate_extras_needed(void *opaque)
84 {
85     qemu_or_irq *s = OR_IRQ(opaque);
86 
87     return s->num_lines >= OLD_MAX_OR_LINES;
88 }
89 
90 static const VMStateDescription vmstate_or_irq_extras = {
91     .name = "or-irq-extras",
92     .version_id = 1,
93     .minimum_version_id = 1,
94     .needed = vmstate_extras_needed,
95     .fields = (VMStateField[]) {
96         VMSTATE_VARRAY_UINT16_UNSAFE(levels, qemu_or_irq, num_lines, 0,
97                                      vmstate_info_bool, bool),
98         VMSTATE_END_OF_LIST(),
99     },
100 };
101 
102 static const VMStateDescription vmstate_or_irq = {
103     .name = TYPE_OR_IRQ,
104     .version_id = 1,
105     .minimum_version_id = 1,
106     .fields = (VMStateField[]) {
107         VMSTATE_BOOL_SUB_ARRAY(levels, qemu_or_irq, 0, OLD_MAX_OR_LINES),
108         VMSTATE_END_OF_LIST(),
109     },
110     .subsections = (const VMStateDescription*[]) {
111         &vmstate_or_irq_extras,
112         NULL
113     },
114 };
115 
116 static Property or_irq_properties[] = {
117     DEFINE_PROP_UINT16("num-lines", qemu_or_irq, num_lines, 1),
118     DEFINE_PROP_END_OF_LIST(),
119 };
120 
121 static void or_irq_class_init(ObjectClass *klass, void *data)
122 {
123     DeviceClass *dc = DEVICE_CLASS(klass);
124 
125     dc->reset = or_irq_reset;
126     dc->props = or_irq_properties;
127     dc->realize = or_irq_realize;
128     dc->vmsd = &vmstate_or_irq;
129 
130     /* Reason: Needs to be wired up to work, e.g. see stm32f205_soc.c */
131     dc->user_creatable = false;
132 }
133 
134 static const TypeInfo or_irq_type_info = {
135    .name = TYPE_OR_IRQ,
136    .parent = TYPE_DEVICE,
137    .instance_size = sizeof(qemu_or_irq),
138    .instance_init = or_irq_init,
139    .class_init = or_irq_class_init,
140 };
141 
142 static void or_irq_register_types(void)
143 {
144     type_register_static(&or_irq_type_info);
145 }
146 
147 type_init(or_irq_register_types)
148