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 "qemu/osdep.h" 11 #include "hw/sysbus.h" 12 #include "hw/pci/pci.h" 13 #include "hw/pci/pci_bus.h" 14 #include "hw/pci/pci_host.h" 15 #include "exec/address-spaces.h" 16 #include "qemu/log.h" 17 18 /* Old and buggy versions of QEMU used the wrong mapping from 19 * PCI IRQs to system interrupt lines. Unfortunately the Linux 20 * kernel also had the corresponding bug in setting up interrupts 21 * (so older kernels work on QEMU and not on real hardware). 22 * We automatically detect these broken kernels and flip back 23 * to the broken irq mapping by spotting guest writes to the 24 * PCI_INTERRUPT_LINE register to see where the guest thinks 25 * interrupts are going to be routed. So we start in state 26 * ASSUME_OK on reset, and transition to either BROKEN or 27 * FORCE_OK at the first write to an INTERRUPT_LINE register for 28 * a slot where broken and correct interrupt mapping would differ. 29 * Once in either BROKEN or FORCE_OK we never transition again; 30 * this allows a newer kernel to use the INTERRUPT_LINE 31 * registers arbitrarily once it has indicated that it isn't 32 * broken in its init code somewhere. 33 * 34 * Unfortunately we have to cope with multiple different 35 * variants on the broken kernel behaviour: 36 * phase I (before kernel commit 1bc39ac5d) kernels assume old 37 * QEMU behaviour, so they use IRQ 27 for all slots 38 * phase II (1bc39ac5d and later, but before e3e92a7be6) kernels 39 * swizzle IRQs between slots, but do it wrongly, so they 40 * work only for every fourth PCI card, and only if (like old 41 * QEMU) the PCI host device is at slot 0 rather than where 42 * the h/w actually puts it 43 * phase III (e3e92a7be6 and later) kernels still swizzle IRQs between 44 * slots wrongly, but add a fixed offset of 64 to everything 45 * they write to PCI_INTERRUPT_LINE. 46 * 47 * We live in hope of a mythical phase IV kernel which might 48 * actually behave in ways that work on the hardware. Such a 49 * kernel should probably start off by writing some value neither 50 * 27 nor 91 to slot zero's PCI_INTERRUPT_LINE register to 51 * disable the autodetection. After that it can do what it likes. 52 * 53 * Slot % 4 | hw | I | II | III 54 * ------------------------------- 55 * 0 | 29 | 27 | 27 | 91 56 * 1 | 30 | 27 | 28 | 92 57 * 2 | 27 | 27 | 29 | 93 58 * 3 | 28 | 27 | 30 | 94 59 * 60 * Since our autodetection is not perfect we also provide a 61 * property so the user can make us start in BROKEN or FORCE_OK 62 * on reset if they know they have a bad or good kernel. 63 */ 64 enum { 65 PCI_VPB_IRQMAP_ASSUME_OK, 66 PCI_VPB_IRQMAP_BROKEN, 67 PCI_VPB_IRQMAP_FORCE_OK, 68 }; 69 70 typedef struct { 71 PCIHostState parent_obj; 72 73 qemu_irq irq[4]; 74 MemoryRegion controlregs; 75 MemoryRegion mem_config; 76 MemoryRegion mem_config2; 77 /* Containers representing the PCI address spaces */ 78 MemoryRegion pci_io_space; 79 MemoryRegion pci_mem_space; 80 /* Alias regions into PCI address spaces which we expose as sysbus regions. 81 * The offsets into pci_mem_space are controlled by the imap registers. 82 */ 83 MemoryRegion pci_io_window; 84 MemoryRegion pci_mem_window[3]; 85 PCIBus pci_bus; 86 PCIDevice pci_dev; 87 88 /* Constant for life of device: */ 89 int realview; 90 uint32_t mem_win_size[3]; 91 uint8_t irq_mapping_prop; 92 93 /* Variable state: */ 94 uint32_t imap[3]; 95 uint32_t smap[3]; 96 uint32_t selfid; 97 uint32_t flags; 98 uint8_t irq_mapping; 99 } PCIVPBState; 100 101 static void pci_vpb_update_window(PCIVPBState *s, int i) 102 { 103 /* Adjust the offset of the alias region we use for 104 * the memory window i to account for a change in the 105 * value of the corresponding IMAP register. 106 * Note that the semantics of the IMAP register differ 107 * for realview and versatile variants of the controller. 108 */ 109 hwaddr offset; 110 if (s->realview) { 111 /* Top bits of register (masked according to window size) provide 112 * top bits of PCI address. 113 */ 114 offset = s->imap[i] & ~(s->mem_win_size[i] - 1); 115 } else { 116 /* Bottom 4 bits of register provide top 4 bits of PCI address */ 117 offset = s->imap[i] << 28; 118 } 119 memory_region_set_alias_offset(&s->pci_mem_window[i], offset); 120 } 121 122 static void pci_vpb_update_all_windows(PCIVPBState *s) 123 { 124 /* Update all alias windows based on the current register state */ 125 int i; 126 127 for (i = 0; i < 3; i++) { 128 pci_vpb_update_window(s, i); 129 } 130 } 131 132 static int pci_vpb_post_load(void *opaque, int version_id) 133 { 134 PCIVPBState *s = opaque; 135 pci_vpb_update_all_windows(s); 136 return 0; 137 } 138 139 static const VMStateDescription pci_vpb_vmstate = { 140 .name = "versatile-pci", 141 .version_id = 1, 142 .minimum_version_id = 1, 143 .post_load = pci_vpb_post_load, 144 .fields = (VMStateField[]) { 145 VMSTATE_UINT32_ARRAY(imap, PCIVPBState, 3), 146 VMSTATE_UINT32_ARRAY(smap, PCIVPBState, 3), 147 VMSTATE_UINT32(selfid, PCIVPBState), 148 VMSTATE_UINT32(flags, PCIVPBState), 149 VMSTATE_UINT8(irq_mapping, PCIVPBState), 150 VMSTATE_END_OF_LIST() 151 } 152 }; 153 154 #define TYPE_VERSATILE_PCI "versatile_pci" 155 #define PCI_VPB(obj) \ 156 OBJECT_CHECK(PCIVPBState, (obj), TYPE_VERSATILE_PCI) 157 158 #define TYPE_VERSATILE_PCI_HOST "versatile_pci_host" 159 #define PCI_VPB_HOST(obj) \ 160 OBJECT_CHECK(PCIDevice, (obj), TYPE_VERSATILE_PCIHOST) 161 162 typedef enum { 163 PCI_IMAP0 = 0x0, 164 PCI_IMAP1 = 0x4, 165 PCI_IMAP2 = 0x8, 166 PCI_SELFID = 0xc, 167 PCI_FLAGS = 0x10, 168 PCI_SMAP0 = 0x14, 169 PCI_SMAP1 = 0x18, 170 PCI_SMAP2 = 0x1c, 171 } PCIVPBControlRegs; 172 173 static void pci_vpb_reg_write(void *opaque, hwaddr addr, 174 uint64_t val, unsigned size) 175 { 176 PCIVPBState *s = opaque; 177 178 switch (addr) { 179 case PCI_IMAP0: 180 case PCI_IMAP1: 181 case PCI_IMAP2: 182 { 183 int win = (addr - PCI_IMAP0) >> 2; 184 s->imap[win] = val; 185 pci_vpb_update_window(s, win); 186 break; 187 } 188 case PCI_SELFID: 189 s->selfid = val; 190 break; 191 case PCI_FLAGS: 192 s->flags = val; 193 break; 194 case PCI_SMAP0: 195 case PCI_SMAP1: 196 case PCI_SMAP2: 197 { 198 int win = (addr - PCI_SMAP0) >> 2; 199 s->smap[win] = val; 200 break; 201 } 202 default: 203 qemu_log_mask(LOG_GUEST_ERROR, 204 "pci_vpb_reg_write: Bad offset %x\n", (int)addr); 205 break; 206 } 207 } 208 209 static uint64_t pci_vpb_reg_read(void *opaque, hwaddr addr, 210 unsigned size) 211 { 212 PCIVPBState *s = opaque; 213 214 switch (addr) { 215 case PCI_IMAP0: 216 case PCI_IMAP1: 217 case PCI_IMAP2: 218 { 219 int win = (addr - PCI_IMAP0) >> 2; 220 return s->imap[win]; 221 } 222 case PCI_SELFID: 223 return s->selfid; 224 case PCI_FLAGS: 225 return s->flags; 226 case PCI_SMAP0: 227 case PCI_SMAP1: 228 case PCI_SMAP2: 229 { 230 int win = (addr - PCI_SMAP0) >> 2; 231 return s->smap[win]; 232 } 233 default: 234 qemu_log_mask(LOG_GUEST_ERROR, 235 "pci_vpb_reg_read: Bad offset %x\n", (int)addr); 236 return 0; 237 } 238 } 239 240 static const MemoryRegionOps pci_vpb_reg_ops = { 241 .read = pci_vpb_reg_read, 242 .write = pci_vpb_reg_write, 243 .endianness = DEVICE_NATIVE_ENDIAN, 244 .valid = { 245 .min_access_size = 4, 246 .max_access_size = 4, 247 }, 248 }; 249 250 static int pci_vpb_broken_irq(int slot, int irq) 251 { 252 /* Determine whether this IRQ value for this slot represents a 253 * known broken Linux kernel behaviour for this slot. 254 * Return one of the PCI_VPB_IRQMAP_ constants: 255 * BROKEN : if this definitely looks like a broken kernel 256 * FORCE_OK : if this definitely looks good 257 * ASSUME_OK : if we can't tell 258 */ 259 slot %= PCI_NUM_PINS; 260 261 if (irq == 27) { 262 if (slot == 2) { 263 /* Might be a Phase I kernel, or might be a fixed kernel, 264 * since slot 2 is where we expect this IRQ. 265 */ 266 return PCI_VPB_IRQMAP_ASSUME_OK; 267 } 268 /* Phase I kernel */ 269 return PCI_VPB_IRQMAP_BROKEN; 270 } 271 if (irq == slot + 27) { 272 /* Phase II kernel */ 273 return PCI_VPB_IRQMAP_BROKEN; 274 } 275 if (irq == slot + 27 + 64) { 276 /* Phase III kernel */ 277 return PCI_VPB_IRQMAP_BROKEN; 278 } 279 /* Anything else must be a fixed kernel, possibly using an 280 * arbitrary irq map. 281 */ 282 return PCI_VPB_IRQMAP_FORCE_OK; 283 } 284 285 static void pci_vpb_config_write(void *opaque, hwaddr addr, 286 uint64_t val, unsigned size) 287 { 288 PCIVPBState *s = opaque; 289 if (!s->realview && (addr & 0xff) == PCI_INTERRUPT_LINE 290 && s->irq_mapping == PCI_VPB_IRQMAP_ASSUME_OK) { 291 uint8_t devfn = addr >> 8; 292 s->irq_mapping = pci_vpb_broken_irq(PCI_SLOT(devfn), val); 293 } 294 pci_data_write(&s->pci_bus, addr, val, size); 295 } 296 297 static uint64_t pci_vpb_config_read(void *opaque, hwaddr addr, 298 unsigned size) 299 { 300 PCIVPBState *s = opaque; 301 uint32_t val; 302 val = pci_data_read(&s->pci_bus, addr, size); 303 return val; 304 } 305 306 static const MemoryRegionOps pci_vpb_config_ops = { 307 .read = pci_vpb_config_read, 308 .write = pci_vpb_config_write, 309 .endianness = DEVICE_NATIVE_ENDIAN, 310 }; 311 312 static int pci_vpb_map_irq(PCIDevice *d, int irq_num) 313 { 314 PCIVPBState *s = container_of(d->bus, PCIVPBState, pci_bus); 315 316 if (s->irq_mapping == PCI_VPB_IRQMAP_BROKEN) { 317 /* Legacy broken IRQ mapping for compatibility with old and 318 * buggy Linux guests 319 */ 320 return irq_num; 321 } 322 323 /* Slot to IRQ mapping for RealView Platform Baseboard 926 backplane 324 * name slot IntA IntB IntC IntD 325 * A 31 IRQ28 IRQ29 IRQ30 IRQ27 326 * B 30 IRQ27 IRQ28 IRQ29 IRQ30 327 * C 29 IRQ30 IRQ27 IRQ28 IRQ29 328 * Slot C is for the host bridge; A and B the peripherals. 329 * Our output irqs 0..3 correspond to the baseboard's 27..30. 330 * 331 * This mapping function takes account of an oddity in the PB926 332 * board wiring, where the FPGA's P_nINTA input is connected to 333 * the INTB connection on the board PCI edge connector, P_nINTB 334 * is connected to INTC, and so on, so everything is one number 335 * further round from where you might expect. 336 */ 337 return pci_swizzle_map_irq_fn(d, irq_num + 2); 338 } 339 340 static int pci_vpb_rv_map_irq(PCIDevice *d, int irq_num) 341 { 342 /* Slot to IRQ mapping for RealView EB and PB1176 backplane 343 * name slot IntA IntB IntC IntD 344 * A 31 IRQ50 IRQ51 IRQ48 IRQ49 345 * B 30 IRQ49 IRQ50 IRQ51 IRQ48 346 * C 29 IRQ48 IRQ49 IRQ50 IRQ51 347 * Slot C is for the host bridge; A and B the peripherals. 348 * Our output irqs 0..3 correspond to the baseboard's 48..51. 349 * 350 * The PB1176 and EB boards don't have the PB926 wiring oddity 351 * described above; P_nINTA connects to INTA, P_nINTB to INTB 352 * and so on, which is why this mapping function is different. 353 */ 354 return pci_swizzle_map_irq_fn(d, irq_num + 3); 355 } 356 357 static void pci_vpb_set_irq(void *opaque, int irq_num, int level) 358 { 359 qemu_irq *pic = opaque; 360 361 qemu_set_irq(pic[irq_num], level); 362 } 363 364 static void pci_vpb_reset(DeviceState *d) 365 { 366 PCIVPBState *s = PCI_VPB(d); 367 368 s->imap[0] = 0; 369 s->imap[1] = 0; 370 s->imap[2] = 0; 371 s->smap[0] = 0; 372 s->smap[1] = 0; 373 s->smap[2] = 0; 374 s->selfid = 0; 375 s->flags = 0; 376 s->irq_mapping = s->irq_mapping_prop; 377 378 pci_vpb_update_all_windows(s); 379 } 380 381 static void pci_vpb_init(Object *obj) 382 { 383 PCIVPBState *s = PCI_VPB(obj); 384 385 /* Window sizes for VersatilePB; realview_pci's init will override */ 386 s->mem_win_size[0] = 0x0c000000; 387 s->mem_win_size[1] = 0x10000000; 388 s->mem_win_size[2] = 0x10000000; 389 } 390 391 static void pci_vpb_realize(DeviceState *dev, Error **errp) 392 { 393 PCIVPBState *s = PCI_VPB(dev); 394 PCIHostState *h = PCI_HOST_BRIDGE(dev); 395 SysBusDevice *sbd = SYS_BUS_DEVICE(dev); 396 pci_map_irq_fn mapfn; 397 int i; 398 399 memory_region_init(&s->pci_io_space, OBJECT(s), "pci_io", 1ULL << 32); 400 memory_region_init(&s->pci_mem_space, OBJECT(s), "pci_mem", 1ULL << 32); 401 402 pci_bus_new_inplace(&s->pci_bus, sizeof(s->pci_bus), dev, "pci", 403 &s->pci_mem_space, &s->pci_io_space, 404 PCI_DEVFN(11, 0), TYPE_PCI_BUS); 405 h->bus = &s->pci_bus; 406 407 object_initialize(&s->pci_dev, sizeof(s->pci_dev), TYPE_VERSATILE_PCI_HOST); 408 qdev_set_parent_bus(DEVICE(&s->pci_dev), BUS(&s->pci_bus)); 409 410 for (i = 0; i < 4; i++) { 411 sysbus_init_irq(sbd, &s->irq[i]); 412 } 413 414 if (s->realview) { 415 mapfn = pci_vpb_rv_map_irq; 416 } else { 417 mapfn = pci_vpb_map_irq; 418 } 419 420 pci_bus_irqs(&s->pci_bus, pci_vpb_set_irq, mapfn, s->irq, 4); 421 422 /* Our memory regions are: 423 * 0 : our control registers 424 * 1 : PCI self config window 425 * 2 : PCI config window 426 * 3 : PCI IO window 427 * 4..6 : PCI memory windows 428 */ 429 memory_region_init_io(&s->controlregs, OBJECT(s), &pci_vpb_reg_ops, s, 430 "pci-vpb-regs", 0x1000); 431 sysbus_init_mmio(sbd, &s->controlregs); 432 memory_region_init_io(&s->mem_config, OBJECT(s), &pci_vpb_config_ops, s, 433 "pci-vpb-selfconfig", 0x1000000); 434 sysbus_init_mmio(sbd, &s->mem_config); 435 memory_region_init_io(&s->mem_config2, OBJECT(s), &pci_vpb_config_ops, s, 436 "pci-vpb-config", 0x1000000); 437 sysbus_init_mmio(sbd, &s->mem_config2); 438 439 /* The window into I/O space is always into a fixed base address; 440 * its size is the same for both realview and versatile. 441 */ 442 memory_region_init_alias(&s->pci_io_window, OBJECT(s), "pci-vbp-io-window", 443 &s->pci_io_space, 0, 0x100000); 444 445 sysbus_init_mmio(sbd, &s->pci_io_space); 446 447 /* Create the alias regions corresponding to our three windows onto 448 * PCI memory space. The sizes vary from board to board; the base 449 * offsets are guest controllable via the IMAP registers. 450 */ 451 for (i = 0; i < 3; i++) { 452 memory_region_init_alias(&s->pci_mem_window[i], OBJECT(s), "pci-vbp-window", 453 &s->pci_mem_space, 0, s->mem_win_size[i]); 454 sysbus_init_mmio(sbd, &s->pci_mem_window[i]); 455 } 456 457 /* TODO Remove once realize propagates to child devices. */ 458 object_property_set_bool(OBJECT(&s->pci_bus), true, "realized", errp); 459 object_property_set_bool(OBJECT(&s->pci_dev), true, "realized", errp); 460 } 461 462 static void versatile_pci_host_realize(PCIDevice *d, Error **errp) 463 { 464 pci_set_word(d->config + PCI_STATUS, 465 PCI_STATUS_66MHZ | PCI_STATUS_DEVSEL_MEDIUM); 466 pci_set_byte(d->config + PCI_LATENCY_TIMER, 0x10); 467 } 468 469 static void versatile_pci_host_class_init(ObjectClass *klass, void *data) 470 { 471 PCIDeviceClass *k = PCI_DEVICE_CLASS(klass); 472 DeviceClass *dc = DEVICE_CLASS(klass); 473 474 k->realize = versatile_pci_host_realize; 475 k->vendor_id = PCI_VENDOR_ID_XILINX; 476 k->device_id = PCI_DEVICE_ID_XILINX_XC2VP30; 477 k->class_id = PCI_CLASS_PROCESSOR_CO; 478 /* 479 * PCI-facing part of the host bridge, not usable without the 480 * host-facing part, which can't be device_add'ed, yet. 481 */ 482 dc->cannot_instantiate_with_device_add_yet = true; 483 } 484 485 static const TypeInfo versatile_pci_host_info = { 486 .name = TYPE_VERSATILE_PCI_HOST, 487 .parent = TYPE_PCI_DEVICE, 488 .instance_size = sizeof(PCIDevice), 489 .class_init = versatile_pci_host_class_init, 490 }; 491 492 static Property pci_vpb_properties[] = { 493 DEFINE_PROP_UINT8("broken-irq-mapping", PCIVPBState, irq_mapping_prop, 494 PCI_VPB_IRQMAP_ASSUME_OK), 495 DEFINE_PROP_END_OF_LIST() 496 }; 497 498 static void pci_vpb_class_init(ObjectClass *klass, void *data) 499 { 500 DeviceClass *dc = DEVICE_CLASS(klass); 501 502 dc->realize = pci_vpb_realize; 503 dc->reset = pci_vpb_reset; 504 dc->vmsd = &pci_vpb_vmstate; 505 dc->props = pci_vpb_properties; 506 } 507 508 static const TypeInfo pci_vpb_info = { 509 .name = TYPE_VERSATILE_PCI, 510 .parent = TYPE_PCI_HOST_BRIDGE, 511 .instance_size = sizeof(PCIVPBState), 512 .instance_init = pci_vpb_init, 513 .class_init = pci_vpb_class_init, 514 }; 515 516 static void pci_realview_init(Object *obj) 517 { 518 PCIVPBState *s = PCI_VPB(obj); 519 520 s->realview = 1; 521 /* The PCI window sizes are different on Realview boards */ 522 s->mem_win_size[0] = 0x01000000; 523 s->mem_win_size[1] = 0x04000000; 524 s->mem_win_size[2] = 0x08000000; 525 } 526 527 static const TypeInfo pci_realview_info = { 528 .name = "realview_pci", 529 .parent = TYPE_VERSATILE_PCI, 530 .instance_init = pci_realview_init, 531 }; 532 533 static void versatile_pci_register_types(void) 534 { 535 type_register_static(&pci_vpb_info); 536 type_register_static(&pci_realview_info); 537 type_register_static(&versatile_pci_host_info); 538 } 539 540 type_init(versatile_pci_register_types) 541