1 | /* "Unimplemented" device |
2 | * |
3 | * This is a dummy device which accepts and logs all accesses. |
4 | * It's useful for stubbing out regions of an SoC or board |
5 | * map which correspond to devices that have not yet been |
6 | * implemented. This is often sufficient to placate initial |
7 | * guest device driver probing such that the system will |
8 | * come up. |
9 | * |
10 | * Copyright Linaro Limited, 2017 |
11 | * Written by Peter Maydell |
12 | */ |
13 | |
14 | #include "qemu/osdep.h" |
15 | #include "hw/sysbus.h" |
16 | #include "hw/misc/unimp.h" |
17 | #include "qemu/log.h" |
18 | #include "qemu/module.h" |
19 | #include "qapi/error.h" |
20 | |
21 | static uint64_t unimp_read(void *opaque, hwaddr offset, unsigned size) |
22 | { |
23 | UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(opaque); |
24 | |
25 | qemu_log_mask(LOG_UNIMP, "%s: unimplemented device read " |
26 | "(size %d, offset 0x%" HWADDR_PRIx ")\n" , |
27 | s->name, size, offset); |
28 | return 0; |
29 | } |
30 | |
31 | static void unimp_write(void *opaque, hwaddr offset, |
32 | uint64_t value, unsigned size) |
33 | { |
34 | UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(opaque); |
35 | |
36 | qemu_log_mask(LOG_UNIMP, "%s: unimplemented device write " |
37 | "(size %d, value 0x%" PRIx64 |
38 | ", offset 0x%" HWADDR_PRIx ")\n" , |
39 | s->name, size, value, offset); |
40 | } |
41 | |
42 | static const MemoryRegionOps unimp_ops = { |
43 | .read = unimp_read, |
44 | .write = unimp_write, |
45 | .impl.min_access_size = 1, |
46 | .impl.max_access_size = 8, |
47 | .valid.min_access_size = 1, |
48 | .valid.max_access_size = 8, |
49 | .endianness = DEVICE_NATIVE_ENDIAN, |
50 | }; |
51 | |
52 | static void unimp_realize(DeviceState *dev, Error **errp) |
53 | { |
54 | UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(dev); |
55 | |
56 | if (s->size == 0) { |
57 | error_setg(errp, "property 'size' not specified or zero" ); |
58 | return; |
59 | } |
60 | |
61 | if (s->name == NULL) { |
62 | error_setg(errp, "property 'name' not specified" ); |
63 | return; |
64 | } |
65 | |
66 | memory_region_init_io(&s->iomem, OBJECT(s), &unimp_ops, s, |
67 | s->name, s->size); |
68 | sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem); |
69 | } |
70 | |
71 | static Property unimp_properties[] = { |
72 | DEFINE_PROP_UINT64("size" , UnimplementedDeviceState, size, 0), |
73 | DEFINE_PROP_STRING("name" , UnimplementedDeviceState, name), |
74 | DEFINE_PROP_END_OF_LIST(), |
75 | }; |
76 | |
77 | static void unimp_class_init(ObjectClass *klass, void *data) |
78 | { |
79 | DeviceClass *dc = DEVICE_CLASS(klass); |
80 | |
81 | dc->realize = unimp_realize; |
82 | dc->props = unimp_properties; |
83 | } |
84 | |
85 | static const TypeInfo unimp_info = { |
86 | .name = TYPE_UNIMPLEMENTED_DEVICE, |
87 | .parent = TYPE_SYS_BUS_DEVICE, |
88 | .instance_size = sizeof(UnimplementedDeviceState), |
89 | .class_init = unimp_class_init, |
90 | }; |
91 | |
92 | static void unimp_register_types(void) |
93 | { |
94 | type_register_static(&unimp_info); |
95 | } |
96 | |
97 | type_init(unimp_register_types) |
98 | |