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 #include "trace.h" 23 24 25 static NubusBus *nubus_find(void) 26 { 27 /* Returns NULL unless there is exactly one nubus device */ 28 return NUBUS_BUS(object_resolve_path_type("", TYPE_NUBUS_BUS, NULL)); 29 } 30 31 static void nubus_slot_write(void *opaque, hwaddr addr, uint64_t val, 32 unsigned int size) 33 { 34 /* read only */ 35 trace_nubus_slot_write(addr, val, size); 36 } 37 38 static uint64_t nubus_slot_read(void *opaque, hwaddr addr, 39 unsigned int size) 40 { 41 trace_nubus_slot_read(addr, size); 42 return 0; 43 } 44 45 static const MemoryRegionOps nubus_slot_ops = { 46 .read = nubus_slot_read, 47 .write = nubus_slot_write, 48 .endianness = DEVICE_BIG_ENDIAN, 49 .valid = { 50 .min_access_size = 1, 51 .max_access_size = 4, 52 }, 53 }; 54 55 static void nubus_super_slot_write(void *opaque, hwaddr addr, uint64_t val, 56 unsigned int size) 57 { 58 /* read only */ 59 trace_nubus_super_slot_write(addr, val, size); 60 } 61 62 static uint64_t nubus_super_slot_read(void *opaque, hwaddr addr, 63 unsigned int size) 64 { 65 trace_nubus_super_slot_read(addr, size); 66 return 0; 67 } 68 69 static const MemoryRegionOps nubus_super_slot_ops = { 70 .read = nubus_super_slot_read, 71 .write = nubus_super_slot_write, 72 .endianness = DEVICE_BIG_ENDIAN, 73 .valid = { 74 .min_access_size = 1, 75 .max_access_size = 4, 76 }, 77 }; 78 79 static void nubus_realize(BusState *bus, Error **errp) 80 { 81 if (!nubus_find()) { 82 error_setg(errp, "at most one %s device is permitted", TYPE_NUBUS_BUS); 83 return; 84 } 85 } 86 87 static void nubus_init(Object *obj) 88 { 89 NubusBus *nubus = NUBUS_BUS(obj); 90 91 memory_region_init_io(&nubus->super_slot_io, obj, &nubus_super_slot_ops, 92 nubus, "nubus-super-slots", 93 (NUBUS_SUPER_SLOT_NB + 1) * NUBUS_SUPER_SLOT_SIZE); 94 95 memory_region_init_io(&nubus->slot_io, obj, &nubus_slot_ops, 96 nubus, "nubus-slots", 97 NUBUS_SLOT_NB * NUBUS_SLOT_SIZE); 98 99 nubus->slot_available_mask = MAKE_64BIT_MASK(NUBUS_FIRST_SLOT, 100 NUBUS_SLOT_NB); 101 } 102 103 static char *nubus_get_dev_path(DeviceState *dev) 104 { 105 NubusDevice *nd = NUBUS_DEVICE(dev); 106 BusState *bus = qdev_get_parent_bus(dev); 107 char *p = qdev_get_dev_path(bus->parent); 108 109 if (p) { 110 char *ret = g_strdup_printf("%s/%s/%02x", p, bus->name, nd->slot); 111 g_free(p); 112 return ret; 113 } else { 114 return g_strdup_printf("%s/%02x", bus->name, nd->slot); 115 } 116 } 117 118 static bool nubus_check_address(BusState *bus, DeviceState *dev, Error **errp) 119 { 120 NubusDevice *nd = NUBUS_DEVICE(dev); 121 NubusBus *nubus = NUBUS_BUS(bus); 122 123 if (nd->slot == -1) { 124 /* No slot specified, find first available free slot */ 125 int s = ctz32(nubus->slot_available_mask); 126 if (s != 32) { 127 nd->slot = s; 128 } else { 129 error_setg(errp, "Cannot register nubus card, no free slot " 130 "available"); 131 return false; 132 } 133 } else { 134 /* Slot specified, make sure the slot is available */ 135 if (!(nubus->slot_available_mask & BIT(nd->slot))) { 136 error_setg(errp, "Cannot register nubus card, slot %d is " 137 "unavailable or already occupied", nd->slot); 138 return false; 139 } 140 } 141 142 nubus->slot_available_mask &= ~BIT(nd->slot); 143 return true; 144 } 145 146 static void nubus_class_init(ObjectClass *oc, void *data) 147 { 148 BusClass *bc = BUS_CLASS(oc); 149 150 bc->realize = nubus_realize; 151 bc->check_address = nubus_check_address; 152 bc->get_dev_path = nubus_get_dev_path; 153 } 154 155 static const TypeInfo nubus_bus_info = { 156 .name = TYPE_NUBUS_BUS, 157 .parent = TYPE_BUS, 158 .instance_size = sizeof(NubusBus), 159 .instance_init = nubus_init, 160 .class_init = nubus_class_init, 161 }; 162 163 static void nubus_register_types(void) 164 { 165 type_register_static(&nubus_bus_info); 166 } 167 168 type_init(nubus_register_types) 169