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 "qemu/osdep.h" 13 #include "hw/sysbus.h" 14 #include "qemu/module.h" 15 #include "hw/qdev-properties.h" 16 #include "hw/empty_slot.h" 17 18 //#define DEBUG_EMPTY_SLOT 19 20 #ifdef DEBUG_EMPTY_SLOT 21 #define DPRINTF(fmt, ...) \ 22 do { printf("empty_slot: " fmt , ## __VA_ARGS__); } while (0) 23 #else 24 #define DPRINTF(fmt, ...) do {} while (0) 25 #endif 26 27 #define TYPE_EMPTY_SLOT "empty_slot" 28 #define EMPTY_SLOT(obj) OBJECT_CHECK(EmptySlot, (obj), TYPE_EMPTY_SLOT) 29 30 typedef struct EmptySlot { 31 SysBusDevice parent_obj; 32 33 MemoryRegion iomem; 34 char *name; 35 uint64_t size; 36 } EmptySlot; 37 38 static uint64_t empty_slot_read(void *opaque, hwaddr addr, 39 unsigned size) 40 { 41 DPRINTF("read from " TARGET_FMT_plx "\n", addr); 42 return 0; 43 } 44 45 static void empty_slot_write(void *opaque, hwaddr addr, 46 uint64_t val, unsigned size) 47 { 48 DPRINTF("write 0x%x to " TARGET_FMT_plx "\n", (unsigned)val, addr); 49 } 50 51 static const MemoryRegionOps empty_slot_ops = { 52 .read = empty_slot_read, 53 .write = empty_slot_write, 54 .endianness = DEVICE_NATIVE_ENDIAN, 55 }; 56 57 void empty_slot_init(hwaddr addr, uint64_t slot_size) 58 { 59 if (slot_size > 0) { 60 /* Only empty slots larger than 0 byte need handling. */ 61 DeviceState *dev; 62 63 dev = qdev_create(NULL, TYPE_EMPTY_SLOT); 64 65 qdev_prop_set_uint64(dev, "size", slot_size); 66 qdev_init_nofail(dev); 67 68 sysbus_mmio_map_overlap(SYS_BUS_DEVICE(dev), 0, addr, -10000); 69 } 70 } 71 72 static void empty_slot_realize(DeviceState *dev, Error **errp) 73 { 74 EmptySlot *s = EMPTY_SLOT(dev); 75 76 if (s->name == NULL) { 77 s->name = g_strdup("empty-slot"); 78 } 79 memory_region_init_io(&s->iomem, OBJECT(s), &empty_slot_ops, s, 80 s->name, s->size); 81 sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem); 82 } 83 84 static Property empty_slot_properties[] = { 85 DEFINE_PROP_UINT64("size", EmptySlot, size, 0), 86 DEFINE_PROP_STRING("name", EmptySlot, name), 87 DEFINE_PROP_END_OF_LIST(), 88 }; 89 90 static void empty_slot_class_init(ObjectClass *klass, void *data) 91 { 92 DeviceClass *dc = DEVICE_CLASS(klass); 93 94 dc->realize = empty_slot_realize; 95 device_class_set_props(dc, empty_slot_properties); 96 } 97 98 static const TypeInfo empty_slot_info = { 99 .name = TYPE_EMPTY_SLOT, 100 .parent = TYPE_SYS_BUS_DEVICE, 101 .instance_size = sizeof(EmptySlot), 102 .class_init = empty_slot_class_init, 103 }; 104 105 static void empty_slot_register_types(void) 106 { 107 type_register_static(&empty_slot_info); 108 } 109 110 type_init(empty_slot_register_types) 111