Statistics
| Branch: | Revision:

root / hw / empty_slot.c @ 8c43a6f0

History | View | Annotate | Download (2.3 kB)

1
/*
2
 * QEMU Empty Slot
3
 *
4
 * The empty_slot device emulates known to a bus but not connected devices.
5
 *
6
 * Copyright (c) 2010 Artyom Tarasenko
7
 *
8
 * This code is licensed under the GNU GPL v2 or (at your option) any later
9
 * version.
10
 */
11

    
12
#include "hw.h"
13
#include "sysbus.h"
14
#include "empty_slot.h"
15

    
16
//#define DEBUG_EMPTY_SLOT
17

    
18
#ifdef DEBUG_EMPTY_SLOT
19
#define DPRINTF(fmt, ...)                                       \
20
    do { printf("empty_slot: " fmt , ## __VA_ARGS__); } while (0)
21
#else
22
#define DPRINTF(fmt, ...) do {} while (0)
23
#endif
24

    
25
typedef struct EmptySlot {
26
    SysBusDevice busdev;
27
    MemoryRegion iomem;
28
    uint64_t size;
29
} EmptySlot;
30

    
31
static uint64_t empty_slot_read(void *opaque, hwaddr addr,
32
                                unsigned size)
33
{
34
    DPRINTF("read from " TARGET_FMT_plx "\n", addr);
35
    return 0;
36
}
37

    
38
static void empty_slot_write(void *opaque, hwaddr addr,
39
                             uint64_t val, unsigned size)
40
{
41
    DPRINTF("write 0x%x to " TARGET_FMT_plx "\n", (unsigned)val, addr);
42
}
43

    
44
static const MemoryRegionOps empty_slot_ops = {
45
    .read = empty_slot_read,
46
    .write = empty_slot_write,
47
    .endianness = DEVICE_NATIVE_ENDIAN,
48
};
49

    
50
void empty_slot_init(hwaddr addr, uint64_t slot_size)
51
{
52
    if (slot_size > 0) {
53
        /* Only empty slots larger than 0 byte need handling. */
54
        DeviceState *dev;
55
        SysBusDevice *s;
56
        EmptySlot *e;
57

    
58
        dev = qdev_create(NULL, "empty_slot");
59
        s = sysbus_from_qdev(dev);
60
        e = FROM_SYSBUS(EmptySlot, s);
61
        e->size = slot_size;
62

    
63
        qdev_init_nofail(dev);
64

    
65
        sysbus_mmio_map(s, 0, addr);
66
    }
67
}
68

    
69
static int empty_slot_init1(SysBusDevice *dev)
70
{
71
    EmptySlot *s = FROM_SYSBUS(EmptySlot, dev);
72

    
73
    memory_region_init_io(&s->iomem, &empty_slot_ops, s,
74
                          "empty-slot", s->size);
75
    sysbus_init_mmio(dev, &s->iomem);
76
    return 0;
77
}
78

    
79
static void empty_slot_class_init(ObjectClass *klass, void *data)
80
{
81
    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
82

    
83
    k->init = empty_slot_init1;
84
}
85

    
86
static const TypeInfo empty_slot_info = {
87
    .name          = "empty_slot",
88
    .parent        = TYPE_SYS_BUS_DEVICE,
89
    .instance_size = sizeof(EmptySlot),
90
    .class_init    = empty_slot_class_init,
91
};
92

    
93
static void empty_slot_register_types(void)
94
{
95
    type_register_static(&empty_slot_info);
96
}
97

    
98
type_init(empty_slot_register_types)