blob: 3ba450e1caba88fe703df77cf27aa32d77df92cb [file] [log] [blame]
/*
* QEMU Empty Slot
*
* The empty_slot device emulates known to a bus but not connected devices.
*
* Copyright (c) 2010 Artyom Tarasenko
*
* This code is licensed under the GNU GPL v2 or (at your option) any later
* version.
*/
#include "qemu/osdep.h"
#include "hw/sysbus.h"
#include "qemu/module.h"
#include "hw/empty_slot.h"
//#define DEBUG_EMPTY_SLOT
#ifdef DEBUG_EMPTY_SLOT
#define DPRINTF(fmt, ...) \
do { printf("empty_slot: " fmt , ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) do {} while (0)
#endif
#define TYPE_EMPTY_SLOT "empty_slot"
#define EMPTY_SLOT(obj) OBJECT_CHECK(EmptySlot, (obj), TYPE_EMPTY_SLOT)
typedef struct EmptySlot {
SysBusDevice parent_obj;
MemoryRegion iomem;
uint64_t size;
} EmptySlot;
static uint64_t empty_slot_read(void *opaque, hwaddr addr,
unsigned size)
{
DPRINTF("read from " TARGET_FMT_plx "\n", addr);
return 0;
}
static void empty_slot_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
DPRINTF("write 0x%x to " TARGET_FMT_plx "\n", (unsigned)val, addr);
}
static const MemoryRegionOps empty_slot_ops = {
.read = empty_slot_read,
.write = empty_slot_write,
.endianness = DEVICE_NATIVE_ENDIAN,
};
void empty_slot_init(hwaddr addr, uint64_t slot_size)
{
if (slot_size > 0) {
/* Only empty slots larger than 0 byte need handling. */
DeviceState *dev;
SysBusDevice *s;
EmptySlot *e;
dev = qdev_create(NULL, TYPE_EMPTY_SLOT);
s = SYS_BUS_DEVICE(dev);
e = EMPTY_SLOT(dev);
e->size = slot_size;
qdev_init_nofail(dev);
sysbus_mmio_map(s, 0, addr);
}
}
static void empty_slot_realize(DeviceState *dev, Error **errp)
{
EmptySlot *s = EMPTY_SLOT(dev);
memory_region_init_io(&s->iomem, OBJECT(s), &empty_slot_ops, s,
"empty-slot", s->size);
sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
}
static void empty_slot_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = empty_slot_realize;
}
static const TypeInfo empty_slot_info = {
.name = TYPE_EMPTY_SLOT,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(EmptySlot),
.class_init = empty_slot_class_init,
};
static void empty_slot_register_types(void)
{
type_register_static(&empty_slot_info);
}
type_init(empty_slot_register_types)