hw/core/split-irq.c

   1 /*
   2  * IRQ splitter device.
   3  *
   4  * Copyright (c) 2018 Linaro Limited.
   5  * Written by Peter Maydell
   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 "hw/core/split-irq.h"
  28 #include "qapi/error.h"
  29
  30 static void split_irq_handler(void *opaque, int n, int level)
  31 {
  32     SplitIRQ *s = SPLIT_IRQ(opaque);
  33     int i;
  34
  35     for (i = 0; i < s->num_lines; i++) {
  36         qemu_set_irq(s->out_irq[i], level);
  37     }
  38 }
  39
  40 static void split_irq_init(Object *obj)
  41 {
  42     qdev_init_gpio_in(DEVICE(obj), split_irq_handler, 1);
  43 }
  44
  45 static void split_irq_realize(DeviceState *dev, Error **errp)
  46 {
  47     SplitIRQ *s = SPLIT_IRQ(dev);
  48
  49     if (s->num_lines < 1 || s->num_lines >= MAX_SPLIT_LINES) {
  50         error_setg(errp,
  51                    "IRQ splitter number of lines %d is not between 1 and %d",
  52                    s->num_lines, MAX_SPLIT_LINES);
  53         return;
  54     }
  55
  56     qdev_init_gpio_out(dev, s->out_irq, s->num_lines);
  57 }
  58
  59 static Property split_irq_properties[] = {
  60     DEFINE_PROP_UINT16("num-lines", SplitIRQ, num_lines, 1),
  61     DEFINE_PROP_END_OF_LIST(),
  62 };
  63
  64 static void split_irq_class_init(ObjectClass *klass, void *data)
  65 {
  66     DeviceClass *dc = DEVICE_CLASS(klass);
  67
  68     /* No state to reset or migrate */
  69     dc->props = split_irq_properties;
  70     dc->realize = split_irq_realize;
  71
  72     /* Reason: Needs to be wired up to work */
  73     dc->user_creatable = false;
  74 }
  75
  76 static const TypeInfo split_irq_type_info = {
  77    .name = TYPE_SPLIT_IRQ,
  78    .parent = TYPE_DEVICE,
  79    .instance_size = sizeof(SplitIRQ),
  80    .instance_init = split_irq_init,
  81    .class_init = split_irq_class_init,
  82 };
  83
  84 static void split_irq_register_types(void)
  85 {
  86     type_register_static(&split_irq_type_info);
  87 }
  88
  89 type_init(split_irq_register_types)