1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/arch/arm/kernel/bios32.c 4 * 5 * PCI bios-type initialisation for PCI machines 6 * 7 * Bits taken from various places. 8 */ 9 #include <linux/export.h> 10 #include <linux/kernel.h> 11 #include <linux/pci.h> 12 #include <linux/slab.h> 13 #include <linux/init.h> 14 #include <linux/io.h> 15 16 #include <asm/mach-types.h> 17 #include <asm/mach/map.h> 18 #include <asm/mach/pci.h> 19 20 static int debug_pci; 21 22 /* 23 * We can't use pci_get_device() here since we are 24 * called from interrupt context. 25 */ 26 static void pcibios_bus_report_status(struct pci_bus *bus, u_int status_mask, int warn) 27 { 28 struct pci_dev *dev; 29 30 list_for_each_entry(dev, &bus->devices, bus_list) { 31 u16 status; 32 33 /* 34 * ignore host bridge - we handle 35 * that separately 36 */ 37 if (dev->bus->number == 0 && dev->devfn == 0) 38 continue; 39 40 pci_read_config_word(dev, PCI_STATUS, &status); 41 if (status == 0xffff) 42 continue; 43 44 if ((status & status_mask) == 0) 45 continue; 46 47 /* clear the status errors */ 48 pci_write_config_word(dev, PCI_STATUS, status & status_mask); 49 50 if (warn) 51 printk("(%s: %04X) ", pci_name(dev), status); 52 } 53 54 list_for_each_entry(dev, &bus->devices, bus_list) 55 if (dev->subordinate) 56 pcibios_bus_report_status(dev->subordinate, status_mask, warn); 57 } 58 59 void pcibios_report_status(u_int status_mask, int warn) 60 { 61 struct pci_bus *bus; 62 63 list_for_each_entry(bus, &pci_root_buses, node) 64 pcibios_bus_report_status(bus, status_mask, warn); 65 } 66 67 /* 68 * We don't use this to fix the device, but initialisation of it. 69 * It's not the correct use for this, but it works. 70 * Note that the arbiter/ISA bridge appears to be buggy, specifically in 71 * the following area: 72 * 1. park on CPU 73 * 2. ISA bridge ping-pong 74 * 3. ISA bridge master handling of target RETRY 75 * 76 * Bug 3 is responsible for the sound DMA grinding to a halt. We now 77 * live with bug 2. 78 */ 79 static void pci_fixup_83c553(struct pci_dev *dev) 80 { 81 /* 82 * Set memory region to start at address 0, and enable IO 83 */ 84 pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, PCI_BASE_ADDRESS_SPACE_MEMORY); 85 pci_write_config_word(dev, PCI_COMMAND, PCI_COMMAND_IO); 86 87 dev->resource[0].end -= dev->resource[0].start; 88 dev->resource[0].start = 0; 89 90 /* 91 * All memory requests from ISA to be channelled to PCI 92 */ 93 pci_write_config_byte(dev, 0x48, 0xff); 94 95 /* 96 * Enable ping-pong on bus master to ISA bridge transactions. 97 * This improves the sound DMA substantially. The fixed 98 * priority arbiter also helps (see below). 99 */ 100 pci_write_config_byte(dev, 0x42, 0x01); 101 102 /* 103 * Enable PCI retry 104 */ 105 pci_write_config_byte(dev, 0x40, 0x22); 106 107 /* 108 * We used to set the arbiter to "park on last master" (bit 109 * 1 set), but unfortunately the CyberPro does not park the 110 * bus. We must therefore park on CPU. Unfortunately, this 111 * may trigger yet another bug in the 553. 112 */ 113 pci_write_config_byte(dev, 0x83, 0x02); 114 115 /* 116 * Make the ISA DMA request lowest priority, and disable 117 * rotating priorities completely. 118 */ 119 pci_write_config_byte(dev, 0x80, 0x11); 120 pci_write_config_byte(dev, 0x81, 0x00); 121 122 /* 123 * Route INTA input to IRQ 11, and set IRQ11 to be level 124 * sensitive. 125 */ 126 pci_write_config_word(dev, 0x44, 0xb000); 127 outb(0x08, 0x4d1); 128 } 129 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_83C553, pci_fixup_83c553); 130 131 static void pci_fixup_unassign(struct pci_dev *dev) 132 { 133 dev->resource[0].end -= dev->resource[0].start; 134 dev->resource[0].start = 0; 135 } 136 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND2, PCI_DEVICE_ID_WINBOND2_89C940F, pci_fixup_unassign); 137 138 /* 139 * Prevent the PCI layer from seeing the resources allocated to this device 140 * if it is the host bridge by marking it as such. These resources are of 141 * no consequence to the PCI layer (they are handled elsewhere). 142 */ 143 static void pci_fixup_dec21285(struct pci_dev *dev) 144 { 145 if (dev->devfn == 0) { 146 struct resource *r; 147 148 dev->class &= 0xff; 149 dev->class |= PCI_CLASS_BRIDGE_HOST << 8; 150 pci_dev_for_each_resource(dev, r) { 151 r->start = 0; 152 r->end = 0; 153 r->flags = 0; 154 } 155 } 156 } 157 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_21285, pci_fixup_dec21285); 158 159 /* 160 * PCI IDE controllers use non-standard I/O port decoding, respect it. 161 */ 162 static void pci_fixup_ide_bases(struct pci_dev *dev) 163 { 164 struct resource *r; 165 166 if ((dev->class >> 8) != PCI_CLASS_STORAGE_IDE) 167 return; 168 169 pci_dev_for_each_resource(dev, r) { 170 if ((r->start & ~0x80) == 0x374) { 171 r->start |= 2; 172 r->end = r->start; 173 } 174 } 175 } 176 DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pci_fixup_ide_bases); 177 178 /* 179 * Put the DEC21142 to sleep 180 */ 181 static void pci_fixup_dec21142(struct pci_dev *dev) 182 { 183 pci_write_config_dword(dev, 0x40, 0x80000000); 184 } 185 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC, PCI_DEVICE_ID_DEC_21142, pci_fixup_dec21142); 186 187 /* 188 * The CY82C693 needs some rather major fixups to ensure that it does 189 * the right thing. Idea from the Alpha people, with a few additions. 190 * 191 * We ensure that the IDE base registers are set to 1f0/3f4 for the 192 * primary bus, and 170/374 for the secondary bus. Also, hide them 193 * from the PCI subsystem view as well so we won't try to perform 194 * our own auto-configuration on them. 195 * 196 * In addition, we ensure that the PCI IDE interrupts are routed to 197 * IRQ 14 and IRQ 15 respectively. 198 * 199 * The above gets us to a point where the IDE on this device is 200 * functional. However, The CY82C693U _does not work_ in bus 201 * master mode without locking the PCI bus solid. 202 */ 203 static void pci_fixup_cy82c693(struct pci_dev *dev) 204 { 205 if ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE) { 206 u32 base0, base1; 207 208 if (dev->class & 0x80) { /* primary */ 209 base0 = 0x1f0; 210 base1 = 0x3f4; 211 } else { /* secondary */ 212 base0 = 0x170; 213 base1 = 0x374; 214 } 215 216 pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, 217 base0 | PCI_BASE_ADDRESS_SPACE_IO); 218 pci_write_config_dword(dev, PCI_BASE_ADDRESS_1, 219 base1 | PCI_BASE_ADDRESS_SPACE_IO); 220 221 dev->resource[0].start = 0; 222 dev->resource[0].end = 0; 223 dev->resource[0].flags = 0; 224 225 dev->resource[1].start = 0; 226 dev->resource[1].end = 0; 227 dev->resource[1].flags = 0; 228 } else if (PCI_FUNC(dev->devfn) == 0) { 229 /* 230 * Setup IDE IRQ routing. 231 */ 232 pci_write_config_byte(dev, 0x4b, 14); 233 pci_write_config_byte(dev, 0x4c, 15); 234 235 /* 236 * Disable FREQACK handshake, enable USB. 237 */ 238 pci_write_config_byte(dev, 0x4d, 0x41); 239 240 /* 241 * Enable PCI retry, and PCI post-write buffer. 242 */ 243 pci_write_config_byte(dev, 0x44, 0x17); 244 245 /* 246 * Enable ISA master and DMA post write buffering. 247 */ 248 pci_write_config_byte(dev, 0x45, 0x03); 249 } 250 } 251 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CONTAQ, PCI_DEVICE_ID_CONTAQ_82C693, pci_fixup_cy82c693); 252 253 /* 254 * If the bus contains any of these devices, then we must not turn on 255 * parity checking of any kind. Currently this is CyberPro 20x0 only. 256 */ 257 static inline int pdev_bad_for_parity(struct pci_dev *dev) 258 { 259 return ((dev->vendor == PCI_VENDOR_ID_INTERG && 260 (dev->device == PCI_DEVICE_ID_INTERG_2000 || 261 dev->device == PCI_DEVICE_ID_INTERG_2010)) || 262 (dev->vendor == PCI_VENDOR_ID_ITE && 263 dev->device == PCI_DEVICE_ID_ITE_8152)); 264 265 } 266 267 /* 268 * pcibios_fixup_bus - Called after each bus is probed, 269 * but before its children are examined. 270 */ 271 void pcibios_fixup_bus(struct pci_bus *bus) 272 { 273 struct pci_dev *dev; 274 u16 features = PCI_COMMAND_SERR | PCI_COMMAND_PARITY | PCI_COMMAND_FAST_BACK; 275 276 /* 277 * Walk the devices on this bus, working out what we can 278 * and can't support. 279 */ 280 list_for_each_entry(dev, &bus->devices, bus_list) { 281 u16 status; 282 283 pci_read_config_word(dev, PCI_STATUS, &status); 284 285 /* 286 * If any device on this bus does not support fast back 287 * to back transfers, then the bus as a whole is not able 288 * to support them. Having fast back to back transfers 289 * on saves us one PCI cycle per transaction. 290 */ 291 if (!(status & PCI_STATUS_FAST_BACK)) 292 features &= ~PCI_COMMAND_FAST_BACK; 293 294 if (pdev_bad_for_parity(dev)) 295 features &= ~(PCI_COMMAND_SERR | PCI_COMMAND_PARITY); 296 297 switch (dev->class >> 8) { 298 case PCI_CLASS_BRIDGE_PCI: 299 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &status); 300 status |= PCI_BRIDGE_CTL_PARITY|PCI_BRIDGE_CTL_MASTER_ABORT; 301 status &= ~(PCI_BRIDGE_CTL_BUS_RESET|PCI_BRIDGE_CTL_FAST_BACK); 302 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, status); 303 break; 304 305 case PCI_CLASS_BRIDGE_CARDBUS: 306 pci_read_config_word(dev, PCI_CB_BRIDGE_CONTROL, &status); 307 status |= PCI_CB_BRIDGE_CTL_PARITY|PCI_CB_BRIDGE_CTL_MASTER_ABORT; 308 pci_write_config_word(dev, PCI_CB_BRIDGE_CONTROL, status); 309 break; 310 } 311 } 312 313 /* 314 * Now walk the devices again, this time setting them up. 315 */ 316 list_for_each_entry(dev, &bus->devices, bus_list) { 317 u16 cmd; 318 319 pci_read_config_word(dev, PCI_COMMAND, &cmd); 320 cmd |= features; 321 pci_write_config_word(dev, PCI_COMMAND, cmd); 322 323 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 324 L1_CACHE_BYTES >> 2); 325 } 326 327 /* 328 * Propagate the flags to the PCI bridge. 329 */ 330 if (bus->self && bus->self->hdr_type == PCI_HEADER_TYPE_BRIDGE) { 331 if (features & PCI_COMMAND_FAST_BACK) 332 bus->bridge_ctl |= PCI_BRIDGE_CTL_FAST_BACK; 333 if (features & PCI_COMMAND_PARITY) 334 bus->bridge_ctl |= PCI_BRIDGE_CTL_PARITY; 335 } 336 337 /* 338 * Report what we did for this bus 339 */ 340 pr_info("PCI: bus%d: Fast back to back transfers %sabled\n", 341 bus->number, (features & PCI_COMMAND_FAST_BACK) ? "en" : "dis"); 342 } 343 EXPORT_SYMBOL(pcibios_fixup_bus); 344 345 /* 346 * Swizzle the device pin each time we cross a bridge. If a platform does 347 * not provide a swizzle function, we perform the standard PCI swizzling. 348 * 349 * The default swizzling walks up the bus tree one level at a time, applying 350 * the standard swizzle function at each step, stopping when it finds the PCI 351 * root bus. This will return the slot number of the bridge device on the 352 * root bus and the interrupt pin on that device which should correspond 353 * with the downstream device interrupt. 354 * 355 * Platforms may override this, in which case the slot and pin returned 356 * depend entirely on the platform code. However, please note that the 357 * PCI standard swizzle is implemented on plug-in cards and Cardbus based 358 * PCI extenders, so it can not be ignored. 359 */ 360 static u8 pcibios_swizzle(struct pci_dev *dev, u8 *pin) 361 { 362 struct pci_sys_data *sys = dev->sysdata; 363 int slot, oldpin = *pin; 364 365 if (sys->swizzle) 366 slot = sys->swizzle(dev, pin); 367 else 368 slot = pci_common_swizzle(dev, pin); 369 370 if (debug_pci) 371 printk("PCI: %s swizzling pin %d => pin %d slot %d\n", 372 pci_name(dev), oldpin, *pin, slot); 373 374 return slot; 375 } 376 377 /* 378 * Map a slot/pin to an IRQ. 379 */ 380 static int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) 381 { 382 struct pci_sys_data *sys = dev->sysdata; 383 int irq = -1; 384 385 if (sys->map_irq) 386 irq = sys->map_irq(dev, slot, pin); 387 388 if (debug_pci) 389 printk("PCI: %s mapping slot %d pin %d => irq %d\n", 390 pci_name(dev), slot, pin, irq); 391 392 return irq; 393 } 394 395 static int pcibios_init_resource(int busnr, struct pci_sys_data *sys) 396 { 397 int ret; 398 struct resource_entry *window; 399 400 if (list_empty(&sys->resources)) { 401 pci_add_resource_offset(&sys->resources, 402 &iomem_resource, sys->mem_offset); 403 } 404 405 resource_list_for_each_entry(window, &sys->resources) 406 if (resource_type(window->res) == IORESOURCE_IO) 407 return 0; 408 409 sys->io_res.start = (busnr * SZ_64K) ? : pcibios_min_io; 410 sys->io_res.end = (busnr + 1) * SZ_64K - 1; 411 sys->io_res.flags = IORESOURCE_IO; 412 sys->io_res.name = sys->io_res_name; 413 sprintf(sys->io_res_name, "PCI%d I/O", busnr); 414 415 ret = request_resource(&ioport_resource, &sys->io_res); 416 if (ret) { 417 pr_err("PCI: unable to allocate I/O port region (%d)\n", ret); 418 return ret; 419 } 420 pci_add_resource_offset(&sys->resources, &sys->io_res, 421 sys->io_offset); 422 423 return 0; 424 } 425 426 static void pcibios_init_hw(struct device *parent, struct hw_pci *hw, 427 struct list_head *head) 428 { 429 struct pci_sys_data *sys = NULL; 430 int ret; 431 int nr, busnr; 432 433 for (nr = busnr = 0; nr < hw->nr_controllers; nr++) { 434 struct pci_host_bridge *bridge; 435 436 bridge = pci_alloc_host_bridge(sizeof(struct pci_sys_data)); 437 if (WARN(!bridge, "PCI: unable to allocate bridge!")) 438 break; 439 440 sys = pci_host_bridge_priv(bridge); 441 442 sys->busnr = busnr; 443 sys->swizzle = hw->swizzle; 444 sys->map_irq = hw->map_irq; 445 INIT_LIST_HEAD(&sys->resources); 446 447 if (hw->private_data) 448 sys->private_data = hw->private_data[nr]; 449 450 ret = hw->setup(nr, sys); 451 452 if (ret > 0) { 453 454 ret = pcibios_init_resource(nr, sys); 455 if (ret) { 456 pci_free_host_bridge(bridge); 457 break; 458 } 459 460 bridge->map_irq = pcibios_map_irq; 461 bridge->swizzle_irq = pcibios_swizzle; 462 463 if (hw->scan) 464 ret = hw->scan(nr, bridge); 465 else { 466 list_splice_init(&sys->resources, 467 &bridge->windows); 468 bridge->dev.parent = parent; 469 bridge->sysdata = sys; 470 bridge->busnr = sys->busnr; 471 bridge->ops = hw->ops; 472 473 ret = pci_scan_root_bus_bridge(bridge); 474 } 475 476 if (WARN(ret < 0, "PCI: unable to scan bus!")) { 477 pci_free_host_bridge(bridge); 478 break; 479 } 480 481 sys->bus = bridge->bus; 482 483 busnr = sys->bus->busn_res.end + 1; 484 485 list_add(&sys->node, head); 486 } else { 487 pci_free_host_bridge(bridge); 488 if (ret < 0) 489 break; 490 } 491 } 492 } 493 494 void pci_common_init_dev(struct device *parent, struct hw_pci *hw) 495 { 496 struct pci_sys_data *sys; 497 LIST_HEAD(head); 498 499 pci_add_flags(PCI_REASSIGN_ALL_BUS); 500 if (hw->preinit) 501 hw->preinit(); 502 pcibios_init_hw(parent, hw, &head); 503 if (hw->postinit) 504 hw->postinit(); 505 506 list_for_each_entry(sys, &head, node) { 507 struct pci_bus *bus = sys->bus; 508 509 /* 510 * We insert PCI resources into the iomem_resource and 511 * ioport_resource trees in either pci_bus_claim_resources() 512 * or pci_bus_assign_resources(). 513 */ 514 if (pci_has_flag(PCI_PROBE_ONLY)) { 515 pci_bus_claim_resources(bus); 516 } else { 517 struct pci_bus *child; 518 519 pci_bus_size_bridges(bus); 520 pci_bus_assign_resources(bus); 521 522 list_for_each_entry(child, &bus->children, node) 523 pcie_bus_configure_settings(child); 524 } 525 526 pci_bus_add_devices(bus); 527 } 528 } 529 530 #ifndef CONFIG_PCI_HOST_ITE8152 531 void pcibios_set_master(struct pci_dev *dev) 532 { 533 /* No special bus mastering setup handling */ 534 } 535 #endif 536 537 char * __init pcibios_setup(char *str) 538 { 539 if (!strcmp(str, "debug")) { 540 debug_pci = 1; 541 return NULL; 542 } 543 return str; 544 } 545 546 /* 547 * From arch/i386/kernel/pci-i386.c: 548 * 549 * We need to avoid collisions with `mirrored' VGA ports 550 * and other strange ISA hardware, so we always want the 551 * addresses to be allocated in the 0x000-0x0ff region 552 * modulo 0x400. 553 * 554 * Why? Because some silly external IO cards only decode 555 * the low 10 bits of the IO address. The 0x00-0xff region 556 * is reserved for motherboard devices that decode all 16 557 * bits, so it's ok to allocate at, say, 0x2800-0x28ff, 558 * but we want to try to avoid allocating at 0x2900-0x2bff 559 * which might be mirrored at 0x0100-0x03ff.. 560 */ 561 resource_size_t pcibios_align_resource(void *data, const struct resource *res, 562 resource_size_t size, resource_size_t align) 563 { 564 struct pci_dev *dev = data; 565 resource_size_t start = res->start; 566 struct pci_host_bridge *host_bridge; 567 568 if (res->flags & IORESOURCE_IO && start & 0x300) 569 start = (start + 0x3ff) & ~0x3ff; 570 571 start = (start + align - 1) & ~(align - 1); 572 573 host_bridge = pci_find_host_bridge(dev->bus); 574 575 if (host_bridge->align_resource) 576 return host_bridge->align_resource(dev, res, 577 start, size, align); 578 579 return start; 580 } 581 582 void __init pci_map_io_early(unsigned long pfn) 583 { 584 struct map_desc pci_io_desc = { 585 .virtual = PCI_IO_VIRT_BASE, 586 .type = MT_DEVICE, 587 .length = SZ_64K, 588 }; 589 590 pci_io_desc.pfn = pfn; 591 iotable_init(&pci_io_desc, 1); 592 } 593