qemu/hw/empty_slot.c

93 lines
2.1 KiB
C

/*
* 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 "hw.h"
#include "sysbus.h"
#include "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
typedef struct EmptySlot {
SysBusDevice busdev;
uint64_t size;
} EmptySlot;
static uint32_t empty_slot_readl(void *opaque, target_phys_addr_t addr)
{
DPRINTF("read from " TARGET_FMT_plx "\n", addr);
return 0;
}
static void empty_slot_writel(void *opaque, target_phys_addr_t addr,
uint32_t val)
{
DPRINTF("write 0x%x to " TARGET_FMT_plx "\n", val, addr);
}
CPUReadMemoryFunc * const empty_slot_read[3] = {
empty_slot_readl,
empty_slot_readl,
empty_slot_readl,
};
static CPUWriteMemoryFunc * const empty_slot_write[3] = {
empty_slot_writel,
empty_slot_writel,
empty_slot_writel,
};
void empty_slot_init(target_phys_addr_t addr, uint64_t slot_size)
{
DeviceState *dev;
SysBusDevice *s;
EmptySlot *e;
dev = qdev_create(NULL, "empty_slot");
s = sysbus_from_qdev(dev);
e = FROM_SYSBUS(EmptySlot, s);
e->size = slot_size;
qdev_init_nofail(dev);
sysbus_mmio_map(s, 0, addr);
}
static int empty_slot_init1(SysBusDevice *dev)
{
EmptySlot *s = FROM_SYSBUS(EmptySlot, dev);
ram_addr_t empty_slot_offset;
empty_slot_offset = cpu_register_io_memory(empty_slot_read,
empty_slot_write, s);
sysbus_init_mmio(dev, s->size, empty_slot_offset | IO_MEM_RAM);
return 0;
}
static SysBusDeviceInfo empty_slot_info = {
.init = empty_slot_init1,
.qdev.name = "empty_slot",
.qdev.size = sizeof(EmptySlot),
};
static void empty_slot_register_devices(void)
{
sysbus_register_withprop(&empty_slot_info);
}
device_init(empty_slot_register_devices);