1 /* 2 * QEMU Macintosh Nubus 3 * 4 * Copyright (c) 2013-2018 Laurent Vivier <laurent@vivier.eu> 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 * 9 */ 10 11 #include "qemu/osdep.h" 12 #include "hw/nubus/nubus.h" 13 #include "qapi/error.h" 14 15 16 static NubusBus *nubus_find(void) 17 { 18 /* Returns NULL unless there is exactly one nubus device */ 19 return NUBUS_BUS(object_resolve_path_type("", TYPE_NUBUS_BUS, NULL)); 20 } 21 22 static void nubus_slot_write(void *opaque, hwaddr addr, uint64_t val, 23 unsigned int size) 24 { 25 /* read only */ 26 } 27 28 29 static uint64_t nubus_slot_read(void *opaque, hwaddr addr, 30 unsigned int size) 31 { 32 return 0; 33 } 34 35 static const MemoryRegionOps nubus_slot_ops = { 36 .read = nubus_slot_read, 37 .write = nubus_slot_write, 38 .endianness = DEVICE_BIG_ENDIAN, 39 .valid = { 40 .min_access_size = 1, 41 .max_access_size = 1, 42 }, 43 }; 44 45 static void nubus_super_slot_write(void *opaque, hwaddr addr, uint64_t val, 46 unsigned int size) 47 { 48 /* read only */ 49 } 50 51 static uint64_t nubus_super_slot_read(void *opaque, hwaddr addr, 52 unsigned int size) 53 { 54 return 0; 55 } 56 57 static const MemoryRegionOps nubus_super_slot_ops = { 58 .read = nubus_super_slot_read, 59 .write = nubus_super_slot_write, 60 .endianness = DEVICE_BIG_ENDIAN, 61 .valid = { 62 .min_access_size = 1, 63 .max_access_size = 1, 64 }, 65 }; 66 67 static void nubus_realize(BusState *bus, Error **errp) 68 { 69 if (!nubus_find()) { 70 error_setg(errp, "at most one %s device is permitted", TYPE_NUBUS_BUS); 71 return; 72 } 73 } 74 75 static void nubus_init(Object *obj) 76 { 77 NubusBus *nubus = NUBUS_BUS(obj); 78 79 memory_region_init_io(&nubus->super_slot_io, obj, &nubus_super_slot_ops, 80 nubus, "nubus-super-slots", 81 NUBUS_SUPER_SLOT_NB * NUBUS_SUPER_SLOT_SIZE); 82 83 memory_region_init_io(&nubus->slot_io, obj, &nubus_slot_ops, 84 nubus, "nubus-slots", 85 NUBUS_SLOT_NB * NUBUS_SLOT_SIZE); 86 87 nubus->current_slot = NUBUS_FIRST_SLOT; 88 } 89 90 static void nubus_class_init(ObjectClass *oc, void *data) 91 { 92 BusClass *bc = BUS_CLASS(oc); 93 94 bc->realize = nubus_realize; 95 } 96 97 static const TypeInfo nubus_bus_info = { 98 .name = TYPE_NUBUS_BUS, 99 .parent = TYPE_BUS, 100 .instance_size = sizeof(NubusBus), 101 .instance_init = nubus_init, 102 .class_init = nubus_class_init, 103 }; 104 105 static void nubus_register_types(void) 106 { 107 type_register_static(&nubus_bus_info); 108 } 109 110 type_init(nubus_register_types) 111