1 /* 2 * QEMU RS/6000 memory controller 3 * 4 * Copyright (c) 2017 Hervé Poussineau 5 * 6 * This program is free software: you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation, either version 2 of the License, or 9 * (at your option) version 3 or any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include "qemu/osdep.h" 21 #include "qemu/units.h" 22 #include "hw/isa/isa.h" 23 #include "hw/qdev-properties.h" 24 #include "migration/vmstate.h" 25 #include "exec/address-spaces.h" 26 #include "hw/boards.h" 27 #include "qapi/error.h" 28 #include "trace.h" 29 30 #define TYPE_RS6000MC "rs6000-mc" 31 #define RS6000MC_DEVICE(obj) \ 32 OBJECT_CHECK(RS6000MCState, (obj), TYPE_RS6000MC) 33 34 typedef struct RS6000MCState { 35 ISADevice parent_obj; 36 /* see US patent 5,684,979 for details (expired 2001-11-04) */ 37 uint32_t ram_size; 38 bool autoconfigure; 39 MemoryRegion simm[6]; 40 unsigned int simm_size[6]; 41 uint32_t end_address[8]; 42 uint8_t port0820_index; 43 PortioList portio; 44 } RS6000MCState; 45 46 /* P0RT 0803 -- SIMM ID Register (32/8 MB) (Read Only) */ 47 48 static uint32_t rs6000mc_port0803_read(void *opaque, uint32_t addr) 49 { 50 RS6000MCState *s = opaque; 51 uint32_t val = 0; 52 int socket; 53 54 /* (1 << socket) indicates 32 MB SIMM at given socket */ 55 for (socket = 0; socket < 6; socket++) { 56 if (s->simm_size[socket] == 32) { 57 val |= (1 << socket); 58 } 59 } 60 61 trace_rs6000mc_id_read(addr, val); 62 return val; 63 } 64 65 /* PORT 0804 -- SIMM Presence Register (Read Only) */ 66 67 static uint32_t rs6000mc_port0804_read(void *opaque, uint32_t addr) 68 { 69 RS6000MCState *s = opaque; 70 uint32_t val = 0xff; 71 int socket; 72 73 /* (1 << socket) indicates SIMM absence at given socket */ 74 for (socket = 0; socket < 6; socket++) { 75 if (s->simm_size[socket]) { 76 val &= ~(1 << socket); 77 } 78 } 79 s->port0820_index = 0; 80 81 trace_rs6000mc_presence_read(addr, val); 82 return val; 83 } 84 85 /* Memory Controller Size Programming Register */ 86 87 static uint32_t rs6000mc_port0820_read(void *opaque, uint32_t addr) 88 { 89 RS6000MCState *s = opaque; 90 uint32_t val = s->end_address[s->port0820_index] & 0x1f; 91 s->port0820_index = (s->port0820_index + 1) & 7; 92 trace_rs6000mc_size_read(addr, val); 93 return val; 94 } 95 96 static void rs6000mc_port0820_write(void *opaque, uint32_t addr, uint32_t val) 97 { 98 RS6000MCState *s = opaque; 99 uint8_t socket = val >> 5; 100 uint32_t end_address = val & 0x1f; 101 102 trace_rs6000mc_size_write(addr, val); 103 s->end_address[socket] = end_address; 104 if (socket > 0 && socket < 7) { 105 if (s->simm_size[socket - 1]) { 106 uint32_t size; 107 uint32_t start_address = 0; 108 if (socket > 1) { 109 start_address = s->end_address[socket - 1]; 110 } 111 112 size = end_address - start_address; 113 memory_region_set_enabled(&s->simm[socket - 1], size != 0); 114 memory_region_set_address(&s->simm[socket - 1], 115 start_address * 8 * MiB); 116 } 117 } 118 } 119 120 /* Read Memory Parity Error */ 121 122 enum { 123 PORT0841_NO_ERROR_DETECTED = 0x01, 124 }; 125 126 static uint32_t rs6000mc_port0841_read(void *opaque, uint32_t addr) 127 { 128 uint32_t val = PORT0841_NO_ERROR_DETECTED; 129 trace_rs6000mc_parity_read(addr, val); 130 return val; 131 } 132 133 static const MemoryRegionPortio rs6000mc_port_list[] = { 134 { 0x803, 1, 1, .read = rs6000mc_port0803_read }, 135 { 0x804, 1, 1, .read = rs6000mc_port0804_read }, 136 { 0x820, 1, 1, .read = rs6000mc_port0820_read, 137 .write = rs6000mc_port0820_write, }, 138 { 0x841, 1, 1, .read = rs6000mc_port0841_read }, 139 PORTIO_END_OF_LIST() 140 }; 141 142 static void rs6000mc_realize(DeviceState *dev, Error **errp) 143 { 144 RS6000MCState *s = RS6000MC_DEVICE(dev); 145 int socket = 0; 146 unsigned int ram_size = s->ram_size / MiB; 147 Error *local_err = NULL; 148 149 while (socket < 6) { 150 if (ram_size >= 64) { 151 s->simm_size[socket] = 32; 152 s->simm_size[socket + 1] = 32; 153 ram_size -= 64; 154 } else if (ram_size >= 16) { 155 s->simm_size[socket] = 8; 156 s->simm_size[socket + 1] = 8; 157 ram_size -= 16; 158 } else { 159 /* Not enough memory */ 160 break; 161 } 162 socket += 2; 163 } 164 165 for (socket = 0; socket < 6; socket++) { 166 if (s->simm_size[socket]) { 167 char name[] = "simm.?"; 168 name[5] = socket + '0'; 169 memory_region_init_ram(&s->simm[socket], OBJECT(dev), name, 170 s->simm_size[socket] * MiB, &local_err); 171 if (local_err) { 172 goto out; 173 } 174 memory_region_add_subregion_overlap(get_system_memory(), 0, 175 &s->simm[socket], socket); 176 } 177 } 178 if (ram_size) { 179 /* unable to push all requested RAM in SIMMs */ 180 error_setg(&local_err, "RAM size incompatible with this board. " 181 "Try again with something else, like %" PRId64 " MB", 182 s->ram_size / MiB - ram_size); 183 goto out; 184 } 185 186 if (s->autoconfigure) { 187 uint32_t start_address = 0; 188 for (socket = 0; socket < 6; socket++) { 189 if (s->simm_size[socket]) { 190 memory_region_set_enabled(&s->simm[socket], true); 191 memory_region_set_address(&s->simm[socket], start_address); 192 start_address += memory_region_size(&s->simm[socket]); 193 } 194 } 195 } 196 197 isa_register_portio_list(ISA_DEVICE(dev), &s->portio, 0x0, 198 rs6000mc_port_list, s, "rs6000mc"); 199 out: 200 error_propagate(errp, local_err); 201 } 202 203 static const VMStateDescription vmstate_rs6000mc = { 204 .name = "rs6000-mc", 205 .version_id = 1, 206 .minimum_version_id = 1, 207 .fields = (VMStateField[]) { 208 VMSTATE_UINT8(port0820_index, RS6000MCState), 209 VMSTATE_END_OF_LIST() 210 }, 211 }; 212 213 static Property rs6000mc_properties[] = { 214 DEFINE_PROP_UINT32("ram-size", RS6000MCState, ram_size, 0), 215 DEFINE_PROP_BOOL("auto-configure", RS6000MCState, autoconfigure, true), 216 DEFINE_PROP_END_OF_LIST() 217 }; 218 219 static void rs6000mc_class_initfn(ObjectClass *klass, void *data) 220 { 221 DeviceClass *dc = DEVICE_CLASS(klass); 222 223 dc->realize = rs6000mc_realize; 224 dc->vmsd = &vmstate_rs6000mc; 225 device_class_set_props(dc, rs6000mc_properties); 226 } 227 228 static const TypeInfo rs6000mc_info = { 229 .name = TYPE_RS6000MC, 230 .parent = TYPE_ISA_DEVICE, 231 .instance_size = sizeof(RS6000MCState), 232 .class_init = rs6000mc_class_initfn, 233 }; 234 235 static void rs6000mc_types(void) 236 { 237 type_register_static(&rs6000mc_info); 238 } 239 240 type_init(rs6000mc_types) 241