hw/core/or-irq.c

   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)