qemu

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/*
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 * QEMU Empty Slot
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 *
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 * The empty_slot device emulates known to a bus but not connected devices.
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 *
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 * Copyright (c) 2010 Artyom Tarasenko
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 *
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 * This code is licensed under the GNU GPL v2 or (at your option) any later
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 * version.
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 */
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#include "qemu/osdep.h"
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#include "hw/sysbus.h"
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#include "hw/qdev-properties.h"
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#include "hw/misc/empty_slot.h"
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#include "qapi/error.h"
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#include "trace.h"
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#include "qom/object.h"
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#define TYPE_EMPTY_SLOT "empty_slot"
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OBJECT_DECLARE_SIMPLE_TYPE(EmptySlot, EMPTY_SLOT)
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struct EmptySlot {
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    SysBusDevice parent_obj;
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    MemoryRegion iomem;
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    char *name;
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    uint64_t size;
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};
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static uint64_t empty_slot_read(void *opaque, hwaddr addr,
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                                unsigned size)
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{
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    EmptySlot *s = EMPTY_SLOT(opaque);
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    trace_empty_slot_write(addr, size << 1, 0, size, s->name);
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    return 0;
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}
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static void empty_slot_write(void *opaque, hwaddr addr,
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                             uint64_t val, unsigned size)
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{
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    EmptySlot *s = EMPTY_SLOT(opaque);
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    trace_empty_slot_write(addr, size << 1, val, size, s->name);
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}
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static const MemoryRegionOps empty_slot_ops = {
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    .read = empty_slot_read,
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    .write = empty_slot_write,
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    .endianness = DEVICE_NATIVE_ENDIAN,
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};
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void empty_slot_init(const char *name, hwaddr addr, uint64_t slot_size)
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{
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    if (slot_size > 0) {
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        /* Only empty slots larger than 0 byte need handling. */
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        DeviceState *dev;
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        dev = qdev_new(TYPE_EMPTY_SLOT);
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        qdev_prop_set_uint64(dev, "size", slot_size);
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        sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
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        sysbus_mmio_map_overlap(SYS_BUS_DEVICE(dev), 0, addr, -10000);
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    }
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}
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static void empty_slot_realize(DeviceState *dev, Error **errp)
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{
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    EmptySlot *s = EMPTY_SLOT(dev);
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    if (s->name == NULL) {
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        s->name = g_strdup("empty-slot");
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    }
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    memory_region_init_io(&s->iomem, OBJECT(s), &empty_slot_ops, s,
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                          s->name, s->size);
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    sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
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}
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static Property empty_slot_properties[] = {
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    DEFINE_PROP_UINT64("size", EmptySlot, size, 0),
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    DEFINE_PROP_STRING("name", EmptySlot, name),
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    DEFINE_PROP_END_OF_LIST(),
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};
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static void empty_slot_class_init(ObjectClass *klass, void *data)
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{
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    DeviceClass *dc = DEVICE_CLASS(klass);
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    dc->realize = empty_slot_realize;
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    device_class_set_props(dc, empty_slot_properties);
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    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
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}
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static const TypeInfo empty_slot_info = {
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    .name          = TYPE_EMPTY_SLOT,
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    .parent        = TYPE_SYS_BUS_DEVICE,
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    .instance_size = sizeof(EmptySlot),
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    .class_init    = empty_slot_class_init,
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};
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static void empty_slot_register_types(void)
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{
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    type_register_static(&empty_slot_info);
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}
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type_init(empty_slot_register_types)
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