xref: /openbmc/qemu/hw/core/or-irq.c (revision 988717b46b6424907618cb845ace9d69062703af)
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 "hw/qdev-properties.h"
29  #include "migration/vmstate.h"
30  #include "qemu/module.h"
31  
32  static void or_irq_handler(void *opaque, int n, int level)
33  {
34      qemu_or_irq *s = OR_IRQ(opaque);
35      int or_level = 0;
36      int i;
37  
38      s->levels[n] = level;
39  
40      for (i = 0; i < s->num_lines; i++) {
41          or_level |= s->levels[i];
42      }
43  
44      qemu_set_irq(s->out_irq, or_level);
45  }
46  
47  static void or_irq_reset(DeviceState *dev)
48  {
49      qemu_or_irq *s = OR_IRQ(dev);
50      int i;
51  
52      for (i = 0; i < MAX_OR_LINES; i++) {
53          s->levels[i] = false;
54      }
55  }
56  
57  static void or_irq_realize(DeviceState *dev, Error **errp)
58  {
59      qemu_or_irq *s = OR_IRQ(dev);
60  
61      assert(s->num_lines <= MAX_OR_LINES);
62  
63      qdev_init_gpio_in(dev, or_irq_handler, s->num_lines);
64  }
65  
66  static void or_irq_init(Object *obj)
67  {
68      qemu_or_irq *s = OR_IRQ(obj);
69  
70      qdev_init_gpio_out(DEVICE(obj), &s->out_irq, 1);
71  }
72  
73  /* The original version of this device had a fixed 16 entries in its
74   * VMState array; devices with more inputs than this need to
75   * migrate the extra lines via a subsection.
76   * The subsection migrates as much of the levels[] array as is needed
77   * (including repeating the first 16 elements), to avoid the awkwardness
78   * of splitting it in two to meet the requirements of VMSTATE_VARRAY_UINT16.
79   */
80  #define OLD_MAX_OR_LINES 16
81  #if MAX_OR_LINES < OLD_MAX_OR_LINES
82  #error MAX_OR_LINES must be at least 16 for migration compatibility
83  #endif
84  
85  static bool vmstate_extras_needed(void *opaque)
86  {
87      qemu_or_irq *s = OR_IRQ(opaque);
88  
89      return s->num_lines >= OLD_MAX_OR_LINES;
90  }
91  
92  static const VMStateDescription vmstate_or_irq_extras = {
93      .name = "or-irq-extras",
94      .version_id = 1,
95      .minimum_version_id = 1,
96      .needed = vmstate_extras_needed,
97      .fields = (VMStateField[]) {
98          VMSTATE_VARRAY_UINT16_UNSAFE(levels, qemu_or_irq, num_lines, 0,
99                                       vmstate_info_bool, bool),
100          VMSTATE_END_OF_LIST(),
101      },
102  };
103  
104  static const VMStateDescription vmstate_or_irq = {
105      .name = TYPE_OR_IRQ,
106      .version_id = 1,
107      .minimum_version_id = 1,
108      .fields = (VMStateField[]) {
109          VMSTATE_BOOL_SUB_ARRAY(levels, qemu_or_irq, 0, OLD_MAX_OR_LINES),
110          VMSTATE_END_OF_LIST(),
111      },
112      .subsections = (const VMStateDescription*[]) {
113          &vmstate_or_irq_extras,
114          NULL
115      },
116  };
117  
118  static Property or_irq_properties[] = {
119      DEFINE_PROP_UINT16("num-lines", qemu_or_irq, num_lines, 1),
120      DEFINE_PROP_END_OF_LIST(),
121  };
122  
123  static void or_irq_class_init(ObjectClass *klass, void *data)
124  {
125      DeviceClass *dc = DEVICE_CLASS(klass);
126  
127      dc->reset = or_irq_reset;
128      device_class_set_props(dc, or_irq_properties);
129      dc->realize = or_irq_realize;
130      dc->vmsd = &vmstate_or_irq;
131  
132      /* Reason: Needs to be wired up to work, e.g. see stm32f205_soc.c */
133      dc->user_creatable = false;
134  }
135  
136  static const TypeInfo or_irq_type_info = {
137     .name = TYPE_OR_IRQ,
138     .parent = TYPE_DEVICE,
139     .instance_size = sizeof(qemu_or_irq),
140     .instance_init = or_irq_init,
141     .class_init = or_irq_class_init,
142  };
143  
144  static void or_irq_register_types(void)
145  {
146      type_register_static(&or_irq_type_info);
147  }
148  
149  type_init(or_irq_register_types)
150