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 /* 12 * References: 13 * Nubus Specification (TI) 14 * http://www.bitsavers.org/pdf/ti/nubus/2242825-0001_NuBus_Spec1983.pdf 15 * 16 * Designing Cards and Drivers for the Macintosh Family (Apple) 17 */ 18 19 #include "qemu/osdep.h" 20 #include "hw/nubus/nubus.h" 21 #include "qapi/error.h" 22 23 24 static NubusBus *nubus_find(void) 25 { 26 /* Returns NULL unless there is exactly one nubus device */ 27 return NUBUS_BUS(object_resolve_path_type("", TYPE_NUBUS_BUS, NULL)); 28 } 29 30 static void nubus_slot_write(void *opaque, hwaddr addr, uint64_t val, 31 unsigned int size) 32 { 33 /* read only */ 34 } 35 36 37 static uint64_t nubus_slot_read(void *opaque, hwaddr addr, 38 unsigned int size) 39 { 40 return 0; 41 } 42 43 static const MemoryRegionOps nubus_slot_ops = { 44 .read = nubus_slot_read, 45 .write = nubus_slot_write, 46 .endianness = DEVICE_BIG_ENDIAN, 47 .valid = { 48 .min_access_size = 1, 49 .max_access_size = 1, 50 }, 51 }; 52 53 static void nubus_super_slot_write(void *opaque, hwaddr addr, uint64_t val, 54 unsigned int size) 55 { 56 /* read only */ 57 } 58 59 static uint64_t nubus_super_slot_read(void *opaque, hwaddr addr, 60 unsigned int size) 61 { 62 return 0; 63 } 64 65 static const MemoryRegionOps nubus_super_slot_ops = { 66 .read = nubus_super_slot_read, 67 .write = nubus_super_slot_write, 68 .endianness = DEVICE_BIG_ENDIAN, 69 .valid = { 70 .min_access_size = 1, 71 .max_access_size = 1, 72 }, 73 }; 74 75 static void nubus_realize(BusState *bus, Error **errp) 76 { 77 if (!nubus_find()) { 78 error_setg(errp, "at most one %s device is permitted", TYPE_NUBUS_BUS); 79 return; 80 } 81 } 82 83 static void nubus_init(Object *obj) 84 { 85 NubusBus *nubus = NUBUS_BUS(obj); 86 87 memory_region_init_io(&nubus->super_slot_io, obj, &nubus_super_slot_ops, 88 nubus, "nubus-super-slots", 89 (NUBUS_SUPER_SLOT_NB + 1) * NUBUS_SUPER_SLOT_SIZE); 90 91 memory_region_init_io(&nubus->slot_io, obj, &nubus_slot_ops, 92 nubus, "nubus-slots", 93 NUBUS_SLOT_NB * NUBUS_SLOT_SIZE); 94 95 nubus->slot_available_mask = MAKE_64BIT_MASK(NUBUS_FIRST_SLOT, 96 NUBUS_SLOT_NB); 97 } 98 99 static char *nubus_get_dev_path(DeviceState *dev) 100 { 101 NubusDevice *nd = NUBUS_DEVICE(dev); 102 BusState *bus = qdev_get_parent_bus(dev); 103 char *p = qdev_get_dev_path(bus->parent); 104 105 if (p) { 106 char *ret = g_strdup_printf("%s/%s/%02x", p, bus->name, nd->slot); 107 g_free(p); 108 return ret; 109 } else { 110 return g_strdup_printf("%s/%02x", bus->name, nd->slot); 111 } 112 } 113 114 static bool nubus_check_address(BusState *bus, DeviceState *dev, Error **errp) 115 { 116 NubusDevice *nd = NUBUS_DEVICE(dev); 117 NubusBus *nubus = NUBUS_BUS(bus); 118 119 if (nd->slot == -1) { 120 /* No slot specified, find first available free slot */ 121 int s = ctz32(nubus->slot_available_mask); 122 if (s != 32) { 123 nd->slot = s; 124 } else { 125 error_setg(errp, "Cannot register nubus card, no free slot " 126 "available"); 127 return false; 128 } 129 } else { 130 /* Slot specified, make sure the slot is available */ 131 if (!(nubus->slot_available_mask & BIT(nd->slot))) { 132 error_setg(errp, "Cannot register nubus card, slot %d is " 133 "unavailable or already occupied", nd->slot); 134 return false; 135 } 136 } 137 138 nubus->slot_available_mask &= ~BIT(nd->slot); 139 return true; 140 } 141 142 static void nubus_class_init(ObjectClass *oc, void *data) 143 { 144 BusClass *bc = BUS_CLASS(oc); 145 146 bc->realize = nubus_realize; 147 bc->check_address = nubus_check_address; 148 bc->get_dev_path = nubus_get_dev_path; 149 } 150 151 static const TypeInfo nubus_bus_info = { 152 .name = TYPE_NUBUS_BUS, 153 .parent = TYPE_BUS, 154 .instance_size = sizeof(NubusBus), 155 .instance_init = nubus_init, 156 .class_init = nubus_class_init, 157 }; 158 159 static void nubus_register_types(void) 160 { 161 type_register_static(&nubus_bus_info); 162 } 163 164 type_init(nubus_register_types) 165