1 /* 2 * ARM Versatile/PB PCI host controller 3 * 4 * Copyright (c) 2006-2009 CodeSourcery. 5 * Written by Paul Brook 6 * 7 * This code is licensed under the LGPL. 8 */ 9 10 #include "hw/sysbus.h" 11 #include "hw/pci/pci.h" 12 #include "hw/pci/pci_bus.h" 13 #include "hw/pci/pci_host.h" 14 #include "exec/address-spaces.h" 15 16 /* Old and buggy versions of QEMU used the wrong mapping from 17 * PCI IRQs to system interrupt lines. Unfortunately the Linux 18 * kernel also had the corresponding bug in setting up interrupts 19 * (so older kernels work on QEMU and not on real hardware). 20 * We automatically detect these broken kernels and flip back 21 * to the broken irq mapping by spotting guest writes to the 22 * PCI_INTERRUPT_LINE register to see where the guest thinks 23 * interrupts are going to be routed. So we start in state 24 * ASSUME_OK on reset, and transition to either BROKEN or 25 * FORCE_OK at the first write to an INTERRUPT_LINE register for 26 * a slot where broken and correct interrupt mapping would differ. 27 * Once in either BROKEN or FORCE_OK we never transition again; 28 * this allows a newer kernel to use the INTERRUPT_LINE 29 * registers arbitrarily once it has indicated that it isn't 30 * broken in its init code somewhere. 31 * 32 * Unfortunately we have to cope with multiple different 33 * variants on the broken kernel behaviour: 34 * phase I (before kernel commit 1bc39ac5d) kernels assume old 35 * QEMU behaviour, so they use IRQ 27 for all slots 36 * phase II (1bc39ac5d and later, but before e3e92a7be6) kernels 37 * swizzle IRQs between slots, but do it wrongly, so they 38 * work only for every fourth PCI card, and only if (like old 39 * QEMU) the PCI host device is at slot 0 rather than where 40 * the h/w actually puts it 41 * phase III (e3e92a7be6 and later) kernels still swizzle IRQs between 42 * slots wrongly, but add a fixed offset of 64 to everything 43 * they write to PCI_INTERRUPT_LINE. 44 * 45 * We live in hope of a mythical phase IV kernel which might 46 * actually behave in ways that work on the hardware. Such a 47 * kernel should probably start off by writing some value neither 48 * 27 nor 91 to slot zero's PCI_INTERRUPT_LINE register to 49 * disable the autodetection. After that it can do what it likes. 50 * 51 * Slot % 4 | hw | I | II | III 52 * ------------------------------- 53 * 0 | 29 | 27 | 27 | 91 54 * 1 | 30 | 27 | 28 | 92 55 * 2 | 27 | 27 | 29 | 93 56 * 3 | 28 | 27 | 30 | 94 57 * 58 * Since our autodetection is not perfect we also provide a 59 * property so the user can make us start in BROKEN or FORCE_OK 60 * on reset if they know they have a bad or good kernel. 61 */ 62 enum { 63 PCI_VPB_IRQMAP_ASSUME_OK, 64 PCI_VPB_IRQMAP_BROKEN, 65 PCI_VPB_IRQMAP_FORCE_OK, 66 }; 67 68 typedef struct { 69 PCIHostState parent_obj; 70 71 qemu_irq irq[4]; 72 MemoryRegion controlregs; 73 MemoryRegion mem_config; 74 MemoryRegion mem_config2; 75 /* Containers representing the PCI address spaces */ 76 MemoryRegion pci_io_space; 77 MemoryRegion pci_mem_space; 78 /* Alias regions into PCI address spaces which we expose as sysbus regions. 79 * The offsets into pci_mem_space are controlled by the imap registers. 80 */ 81 MemoryRegion pci_io_window; 82 MemoryRegion pci_mem_window[3]; 83 PCIBus pci_bus; 84 PCIDevice pci_dev; 85 86 /* Constant for life of device: */ 87 int realview; 88 uint32_t mem_win_size[3]; 89 uint8_t irq_mapping_prop; 90 91 /* Variable state: */ 92 uint32_t imap[3]; 93 uint32_t smap[3]; 94 uint32_t selfid; 95 uint32_t flags; 96 uint8_t irq_mapping; 97 } PCIVPBState; 98 99 static void pci_vpb_update_window(PCIVPBState *s, int i) 100 { 101 /* Adjust the offset of the alias region we use for 102 * the memory window i to account for a change in the 103 * value of the corresponding IMAP register. 104 * Note that the semantics of the IMAP register differ 105 * for realview and versatile variants of the controller. 106 */ 107 hwaddr offset; 108 if (s->realview) { 109 /* Top bits of register (masked according to window size) provide 110 * top bits of PCI address. 111 */ 112 offset = s->imap[i] & ~(s->mem_win_size[i] - 1); 113 } else { 114 /* Bottom 4 bits of register provide top 4 bits of PCI address */ 115 offset = s->imap[i] << 28; 116 } 117 memory_region_set_alias_offset(&s->pci_mem_window[i], offset); 118 } 119 120 static void pci_vpb_update_all_windows(PCIVPBState *s) 121 { 122 /* Update all alias windows based on the current register state */ 123 int i; 124 125 for (i = 0; i < 3; i++) { 126 pci_vpb_update_window(s, i); 127 } 128 } 129 130 static int pci_vpb_post_load(void *opaque, int version_id) 131 { 132 PCIVPBState *s = opaque; 133 pci_vpb_update_all_windows(s); 134 return 0; 135 } 136 137 static const VMStateDescription pci_vpb_vmstate = { 138 .name = "versatile-pci", 139 .version_id = 1, 140 .minimum_version_id = 1, 141 .post_load = pci_vpb_post_load, 142 .fields = (VMStateField[]) { 143 VMSTATE_UINT32_ARRAY(imap, PCIVPBState, 3), 144 VMSTATE_UINT32_ARRAY(smap, PCIVPBState, 3), 145 VMSTATE_UINT32(selfid, PCIVPBState), 146 VMSTATE_UINT32(flags, PCIVPBState), 147 VMSTATE_UINT8(irq_mapping, PCIVPBState), 148 VMSTATE_END_OF_LIST() 149 } 150 }; 151 152 #define TYPE_VERSATILE_PCI "versatile_pci" 153 #define PCI_VPB(obj) \ 154 OBJECT_CHECK(PCIVPBState, (obj), TYPE_VERSATILE_PCI) 155 156 #define TYPE_VERSATILE_PCI_HOST "versatile_pci_host" 157 #define PCI_VPB_HOST(obj) \ 158 OBJECT_CHECK(PCIDevice, (obj), TYPE_VERSATILE_PCIHOST) 159 160 typedef enum { 161 PCI_IMAP0 = 0x0, 162 PCI_IMAP1 = 0x4, 163 PCI_IMAP2 = 0x8, 164 PCI_SELFID = 0xc, 165 PCI_FLAGS = 0x10, 166 PCI_SMAP0 = 0x14, 167 PCI_SMAP1 = 0x18, 168 PCI_SMAP2 = 0x1c, 169 } PCIVPBControlRegs; 170 171 static void pci_vpb_reg_write(void *opaque, hwaddr addr, 172 uint64_t val, unsigned size) 173 { 174 PCIVPBState *s = opaque; 175 176 switch (addr) { 177 case PCI_IMAP0: 178 case PCI_IMAP1: 179 case PCI_IMAP2: 180 { 181 int win = (addr - PCI_IMAP0) >> 2; 182 s->imap[win] = val; 183 pci_vpb_update_window(s, win); 184 break; 185 } 186 case PCI_SELFID: 187 s->selfid = val; 188 break; 189 case PCI_FLAGS: 190 s->flags = val; 191 break; 192 case PCI_SMAP0: 193 case PCI_SMAP1: 194 case PCI_SMAP2: 195 { 196 int win = (addr - PCI_SMAP0) >> 2; 197 s->smap[win] = val; 198 break; 199 } 200 default: 201 qemu_log_mask(LOG_GUEST_ERROR, 202 "pci_vpb_reg_write: Bad offset %x\n", (int)addr); 203 break; 204 } 205 } 206 207 static uint64_t pci_vpb_reg_read(void *opaque, hwaddr addr, 208 unsigned size) 209 { 210 PCIVPBState *s = opaque; 211 212 switch (addr) { 213 case PCI_IMAP0: 214 case PCI_IMAP1: 215 case PCI_IMAP2: 216 { 217 int win = (addr - PCI_IMAP0) >> 2; 218 return s->imap[win]; 219 } 220 case PCI_SELFID: 221 return s->selfid; 222 case PCI_FLAGS: 223 return s->flags; 224 case PCI_SMAP0: 225 case PCI_SMAP1: 226 case PCI_SMAP2: 227 { 228 int win = (addr - PCI_SMAP0) >> 2; 229 return s->smap[win]; 230 } 231 default: 232 qemu_log_mask(LOG_GUEST_ERROR, 233 "pci_vpb_reg_read: Bad offset %x\n", (int)addr); 234 return 0; 235 } 236 } 237 238 static const MemoryRegionOps pci_vpb_reg_ops = { 239 .read = pci_vpb_reg_read, 240 .write = pci_vpb_reg_write, 241 .endianness = DEVICE_NATIVE_ENDIAN, 242 .valid = { 243 .min_access_size = 4, 244 .max_access_size = 4, 245 }, 246 }; 247 248 static int pci_vpb_broken_irq(int slot, int irq) 249 { 250 /* Determine whether this IRQ value for this slot represents a 251 * known broken Linux kernel behaviour for this slot. 252 * Return one of the PCI_VPB_IRQMAP_ constants: 253 * BROKEN : if this definitely looks like a broken kernel 254 * FORCE_OK : if this definitely looks good 255 * ASSUME_OK : if we can't tell 256 */ 257 slot %= PCI_NUM_PINS; 258 259 if (irq == 27) { 260 if (slot == 2) { 261 /* Might be a Phase I kernel, or might be a fixed kernel, 262 * since slot 2 is where we expect this IRQ. 263 */ 264 return PCI_VPB_IRQMAP_ASSUME_OK; 265 } 266 /* Phase I kernel */ 267 return PCI_VPB_IRQMAP_BROKEN; 268 } 269 if (irq == slot + 27) { 270 /* Phase II kernel */ 271 return PCI_VPB_IRQMAP_BROKEN; 272 } 273 if (irq == slot + 27 + 64) { 274 /* Phase III kernel */ 275 return PCI_VPB_IRQMAP_BROKEN; 276 } 277 /* Anything else must be a fixed kernel, possibly using an 278 * arbitrary irq map. 279 */ 280 return PCI_VPB_IRQMAP_FORCE_OK; 281 } 282 283 static void pci_vpb_config_write(void *opaque, hwaddr addr, 284 uint64_t val, unsigned size) 285 { 286 PCIVPBState *s = opaque; 287 if (!s->realview && (addr & 0xff) == PCI_INTERRUPT_LINE 288 && s->irq_mapping == PCI_VPB_IRQMAP_ASSUME_OK) { 289 uint8_t devfn = addr >> 8; 290 s->irq_mapping = pci_vpb_broken_irq(PCI_SLOT(devfn), val); 291 } 292 pci_data_write(&s->pci_bus, addr, val, size); 293 } 294 295 static uint64_t pci_vpb_config_read(void *opaque, hwaddr addr, 296 unsigned size) 297 { 298 PCIVPBState *s = opaque; 299 uint32_t val; 300 val = pci_data_read(&s->pci_bus, addr, size); 301 return val; 302 } 303 304 static const MemoryRegionOps pci_vpb_config_ops = { 305 .read = pci_vpb_config_read, 306 .write = pci_vpb_config_write, 307 .endianness = DEVICE_NATIVE_ENDIAN, 308 }; 309 310 static int pci_vpb_map_irq(PCIDevice *d, int irq_num) 311 { 312 PCIVPBState *s = container_of(d->bus, PCIVPBState, pci_bus); 313 314 if (s->irq_mapping == PCI_VPB_IRQMAP_BROKEN) { 315 /* Legacy broken IRQ mapping for compatibility with old and 316 * buggy Linux guests 317 */ 318 return irq_num; 319 } 320 321 /* Slot to IRQ mapping for RealView Platform Baseboard 926 backplane 322 * name slot IntA IntB IntC IntD 323 * A 31 IRQ28 IRQ29 IRQ30 IRQ27 324 * B 30 IRQ27 IRQ28 IRQ29 IRQ30 325 * C 29 IRQ30 IRQ27 IRQ28 IRQ29 326 * Slot C is for the host bridge; A and B the peripherals. 327 * Our output irqs 0..3 correspond to the baseboard's 27..30. 328 * 329 * This mapping function takes account of an oddity in the PB926 330 * board wiring, where the FPGA's P_nINTA input is connected to 331 * the INTB connection on the board PCI edge connector, P_nINTB 332 * is connected to INTC, and so on, so everything is one number 333 * further round from where you might expect. 334 */ 335 return pci_swizzle_map_irq_fn(d, irq_num + 2); 336 } 337 338 static int pci_vpb_rv_map_irq(PCIDevice *d, int irq_num) 339 { 340 /* Slot to IRQ mapping for RealView EB and PB1176 backplane 341 * name slot IntA IntB IntC IntD 342 * A 31 IRQ50 IRQ51 IRQ48 IRQ49 343 * B 30 IRQ49 IRQ50 IRQ51 IRQ48 344 * C 29 IRQ48 IRQ49 IRQ50 IRQ51 345 * Slot C is for the host bridge; A and B the peripherals. 346 * Our output irqs 0..3 correspond to the baseboard's 48..51. 347 * 348 * The PB1176 and EB boards don't have the PB926 wiring oddity 349 * described above; P_nINTA connects to INTA, P_nINTB to INTB 350 * and so on, which is why this mapping function is different. 351 */ 352 return pci_swizzle_map_irq_fn(d, irq_num + 3); 353 } 354 355 static void pci_vpb_set_irq(void *opaque, int irq_num, int level) 356 { 357 qemu_irq *pic = opaque; 358 359 qemu_set_irq(pic[irq_num], level); 360 } 361 362 static void pci_vpb_reset(DeviceState *d) 363 { 364 PCIVPBState *s = PCI_VPB(d); 365 366 s->imap[0] = 0; 367 s->imap[1] = 0; 368 s->imap[2] = 0; 369 s->smap[0] = 0; 370 s->smap[1] = 0; 371 s->smap[2] = 0; 372 s->selfid = 0; 373 s->flags = 0; 374 s->irq_mapping = s->irq_mapping_prop; 375 376 pci_vpb_update_all_windows(s); 377 } 378 379 static void pci_vpb_init(Object *obj) 380 { 381 PCIHostState *h = PCI_HOST_BRIDGE(obj); 382 PCIVPBState *s = PCI_VPB(obj); 383 384 memory_region_init(&s->pci_io_space, OBJECT(s), "pci_io", 1ULL << 32); 385 memory_region_init(&s->pci_mem_space, OBJECT(s), "pci_mem", 1ULL << 32); 386 387 pci_bus_new_inplace(&s->pci_bus, sizeof(s->pci_bus), DEVICE(obj), "pci", 388 &s->pci_mem_space, &s->pci_io_space, 389 PCI_DEVFN(11, 0), TYPE_PCI_BUS); 390 h->bus = &s->pci_bus; 391 392 object_initialize(&s->pci_dev, sizeof(s->pci_dev), TYPE_VERSATILE_PCI_HOST); 393 qdev_set_parent_bus(DEVICE(&s->pci_dev), BUS(&s->pci_bus)); 394 395 /* Window sizes for VersatilePB; realview_pci's init will override */ 396 s->mem_win_size[0] = 0x0c000000; 397 s->mem_win_size[1] = 0x10000000; 398 s->mem_win_size[2] = 0x10000000; 399 } 400 401 static void pci_vpb_realize(DeviceState *dev, Error **errp) 402 { 403 PCIVPBState *s = PCI_VPB(dev); 404 SysBusDevice *sbd = SYS_BUS_DEVICE(dev); 405 pci_map_irq_fn mapfn; 406 int i; 407 408 for (i = 0; i < 4; i++) { 409 sysbus_init_irq(sbd, &s->irq[i]); 410 } 411 412 if (s->realview) { 413 mapfn = pci_vpb_rv_map_irq; 414 } else { 415 mapfn = pci_vpb_map_irq; 416 } 417 418 pci_bus_irqs(&s->pci_bus, pci_vpb_set_irq, mapfn, s->irq, 4); 419 420 /* Our memory regions are: 421 * 0 : our control registers 422 * 1 : PCI self config window 423 * 2 : PCI config window 424 * 3 : PCI IO window 425 * 4..6 : PCI memory windows 426 */ 427 memory_region_init_io(&s->controlregs, OBJECT(s), &pci_vpb_reg_ops, s, 428 "pci-vpb-regs", 0x1000); 429 sysbus_init_mmio(sbd, &s->controlregs); 430 memory_region_init_io(&s->mem_config, OBJECT(s), &pci_vpb_config_ops, s, 431 "pci-vpb-selfconfig", 0x1000000); 432 sysbus_init_mmio(sbd, &s->mem_config); 433 memory_region_init_io(&s->mem_config2, OBJECT(s), &pci_vpb_config_ops, s, 434 "pci-vpb-config", 0x1000000); 435 sysbus_init_mmio(sbd, &s->mem_config2); 436 437 /* The window into I/O space is always into a fixed base address; 438 * its size is the same for both realview and versatile. 439 */ 440 memory_region_init_alias(&s->pci_io_window, OBJECT(s), "pci-vbp-io-window", 441 &s->pci_io_space, 0, 0x100000); 442 443 sysbus_init_mmio(sbd, &s->pci_io_space); 444 445 /* Create the alias regions corresponding to our three windows onto 446 * PCI memory space. The sizes vary from board to board; the base 447 * offsets are guest controllable via the IMAP registers. 448 */ 449 for (i = 0; i < 3; i++) { 450 memory_region_init_alias(&s->pci_mem_window[i], OBJECT(s), "pci-vbp-window", 451 &s->pci_mem_space, 0, s->mem_win_size[i]); 452 sysbus_init_mmio(sbd, &s->pci_mem_window[i]); 453 } 454 455 /* TODO Remove once realize propagates to child devices. */ 456 object_property_set_bool(OBJECT(&s->pci_dev), true, "realized", errp); 457 } 458 459 static int versatile_pci_host_init(PCIDevice *d) 460 { 461 pci_set_word(d->config + PCI_STATUS, 462 PCI_STATUS_66MHZ | PCI_STATUS_DEVSEL_MEDIUM); 463 pci_set_byte(d->config + PCI_LATENCY_TIMER, 0x10); 464 return 0; 465 } 466 467 static void versatile_pci_host_class_init(ObjectClass *klass, void *data) 468 { 469 PCIDeviceClass *k = PCI_DEVICE_CLASS(klass); 470 DeviceClass *dc = DEVICE_CLASS(klass); 471 472 k->init = versatile_pci_host_init; 473 k->vendor_id = PCI_VENDOR_ID_XILINX; 474 k->device_id = PCI_DEVICE_ID_XILINX_XC2VP30; 475 k->class_id = PCI_CLASS_PROCESSOR_CO; 476 /* 477 * PCI-facing part of the host bridge, not usable without the 478 * host-facing part, which can't be device_add'ed, yet. 479 */ 480 dc->cannot_instantiate_with_device_add_yet = true; 481 } 482 483 static const TypeInfo versatile_pci_host_info = { 484 .name = TYPE_VERSATILE_PCI_HOST, 485 .parent = TYPE_PCI_DEVICE, 486 .instance_size = sizeof(PCIDevice), 487 .class_init = versatile_pci_host_class_init, 488 }; 489 490 static Property pci_vpb_properties[] = { 491 DEFINE_PROP_UINT8("broken-irq-mapping", PCIVPBState, irq_mapping_prop, 492 PCI_VPB_IRQMAP_ASSUME_OK), 493 DEFINE_PROP_END_OF_LIST() 494 }; 495 496 static void pci_vpb_class_init(ObjectClass *klass, void *data) 497 { 498 DeviceClass *dc = DEVICE_CLASS(klass); 499 500 dc->realize = pci_vpb_realize; 501 dc->reset = pci_vpb_reset; 502 dc->vmsd = &pci_vpb_vmstate; 503 dc->props = pci_vpb_properties; 504 } 505 506 static const TypeInfo pci_vpb_info = { 507 .name = TYPE_VERSATILE_PCI, 508 .parent = TYPE_PCI_HOST_BRIDGE, 509 .instance_size = sizeof(PCIVPBState), 510 .instance_init = pci_vpb_init, 511 .class_init = pci_vpb_class_init, 512 }; 513 514 static void pci_realview_init(Object *obj) 515 { 516 PCIVPBState *s = PCI_VPB(obj); 517 518 s->realview = 1; 519 /* The PCI window sizes are different on Realview boards */ 520 s->mem_win_size[0] = 0x01000000; 521 s->mem_win_size[1] = 0x04000000; 522 s->mem_win_size[2] = 0x08000000; 523 } 524 525 static const TypeInfo pci_realview_info = { 526 .name = "realview_pci", 527 .parent = TYPE_VERSATILE_PCI, 528 .instance_init = pci_realview_init, 529 }; 530 531 static void versatile_pci_register_types(void) 532 { 533 type_register_static(&pci_vpb_info); 534 type_register_static(&pci_realview_info); 535 type_register_static(&versatile_pci_host_info); 536 } 537 538 type_init(versatile_pci_register_types) 539