1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Helper routines to scan the device tree for PCI devices and busses 4 * 5 * Migrated out of PowerPC architecture pci_64.c file by Grant Likely 6 * <grant.likely@secretlab.ca> so that these routines are available for 7 * 32 bit also. 8 * 9 * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM 10 * Rework, based on alpha PCI code. 11 * Copyright (c) 2009 Secret Lab Technologies Ltd. 12 */ 13 14 #include <linux/pci.h> 15 #include <linux/export.h> 16 #include <linux/of.h> 17 #include <asm/pci-bridge.h> 18 19 /** 20 * get_int_prop - Decode a u32 from a device tree property 21 */ 22 static u32 get_int_prop(struct device_node *np, const char *name, u32 def) 23 { 24 const __be32 *prop; 25 int len; 26 27 prop = of_get_property(np, name, &len); 28 if (prop && len >= 4) 29 return of_read_number(prop, 1); 30 return def; 31 } 32 33 /** 34 * pci_parse_of_flags - Parse the flags cell of a device tree PCI address 35 * @addr0: value of 1st cell of a device tree PCI address. 36 * @bridge: Set this flag if the address is from a bridge 'ranges' property 37 * 38 * PCI Bus Binding to IEEE Std 1275-1994 39 * 40 * Bit# 33222222 22221111 11111100 00000000 41 * 10987654 32109876 54321098 76543210 42 * phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr 43 * phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh 44 * phys.lo cell: llllllll llllllll llllllll llllllll 45 * 46 * where: 47 * n is 0 if the address is relocatable, 1 otherwise 48 * p is 1 if the addressable region is "prefetchable", 0 otherwise 49 * t is 1 if the address is aliased (for non-relocatable I/O), 50 * below 1 MB (for Memory),or below 64 KB (for relocatable I/O). 51 * ss is the space code, denoting the address space: 52 * 00 denotes Configuration Space 53 * 01 denotes I/O Space 54 * 10 denotes 32-bit-address Memory Space 55 * 11 denotes 64-bit-address Memory Space 56 * bbbbbbbb is the 8-bit Bus Number 57 * ddddd is the 5-bit Device Number 58 * fff is the 3-bit Function Number 59 * rrrrrrrr is the 8-bit Register Number 60 */ 61 #define OF_PCI_ADDR0_SPACE(ss) (((ss)&3)<<24) 62 #define OF_PCI_ADDR0_SPACE_CFG OF_PCI_ADDR0_SPACE(0) 63 #define OF_PCI_ADDR0_SPACE_IO OF_PCI_ADDR0_SPACE(1) 64 #define OF_PCI_ADDR0_SPACE_MMIO32 OF_PCI_ADDR0_SPACE(2) 65 #define OF_PCI_ADDR0_SPACE_MMIO64 OF_PCI_ADDR0_SPACE(3) 66 #define OF_PCI_ADDR0_SPACE_MASK OF_PCI_ADDR0_SPACE(3) 67 #define OF_PCI_ADDR0_RELOC (1UL<<31) 68 #define OF_PCI_ADDR0_PREFETCH (1UL<<30) 69 #define OF_PCI_ADDR0_ALIAS (1UL<<29) 70 #define OF_PCI_ADDR0_BUS 0x00FF0000UL 71 #define OF_PCI_ADDR0_DEV 0x0000F800UL 72 #define OF_PCI_ADDR0_FN 0x00000700UL 73 #define OF_PCI_ADDR0_BARREG 0x000000FFUL 74 75 unsigned int pci_parse_of_flags(u32 addr0, int bridge) 76 { 77 unsigned int flags = 0, as = addr0 & OF_PCI_ADDR0_SPACE_MASK; 78 79 if (as == OF_PCI_ADDR0_SPACE_MMIO32 || as == OF_PCI_ADDR0_SPACE_MMIO64) { 80 flags = IORESOURCE_MEM | PCI_BASE_ADDRESS_SPACE_MEMORY; 81 82 if (as == OF_PCI_ADDR0_SPACE_MMIO64) 83 flags |= PCI_BASE_ADDRESS_MEM_TYPE_64 | IORESOURCE_MEM_64; 84 85 if (addr0 & OF_PCI_ADDR0_ALIAS) 86 flags |= PCI_BASE_ADDRESS_MEM_TYPE_1M; 87 88 if (addr0 & OF_PCI_ADDR0_PREFETCH) 89 flags |= IORESOURCE_PREFETCH | 90 PCI_BASE_ADDRESS_MEM_PREFETCH; 91 92 /* Note: We don't know whether the ROM has been left enabled 93 * by the firmware or not. We mark it as disabled (ie, we do 94 * not set the IORESOURCE_ROM_ENABLE flag) for now rather than 95 * do a config space read, it will be force-enabled if needed 96 */ 97 if (!bridge && (addr0 & OF_PCI_ADDR0_BARREG) == PCI_ROM_ADDRESS) 98 flags |= IORESOURCE_READONLY; 99 100 } else if (as == OF_PCI_ADDR0_SPACE_IO) 101 flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO; 102 103 if (flags) 104 flags |= IORESOURCE_SIZEALIGN; 105 106 return flags; 107 } 108 109 /** 110 * of_pci_parse_addrs - Parse PCI addresses assigned in the device tree node 111 * @node: device tree node for the PCI device 112 * @dev: pci_dev structure for the device 113 * 114 * This function parses the 'assigned-addresses' property of a PCI devices' 115 * device tree node and writes them into the associated pci_dev structure. 116 */ 117 static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev) 118 { 119 u64 base, size; 120 unsigned int flags; 121 struct pci_bus_region region; 122 struct resource *res; 123 const __be32 *addrs; 124 u32 i; 125 int proplen; 126 bool mark_unset = false; 127 128 addrs = of_get_property(node, "assigned-addresses", &proplen); 129 if (!addrs || !proplen) { 130 addrs = of_get_property(node, "reg", &proplen); 131 if (!addrs || !proplen) 132 return; 133 mark_unset = true; 134 } 135 136 pr_debug(" parse addresses (%d bytes) @ %p\n", proplen, addrs); 137 for (; proplen >= 20; proplen -= 20, addrs += 5) { 138 flags = pci_parse_of_flags(of_read_number(addrs, 1), 0); 139 if (!flags) 140 continue; 141 base = of_read_number(&addrs[1], 2); 142 size = of_read_number(&addrs[3], 2); 143 if (!size) 144 continue; 145 i = of_read_number(addrs, 1) & 0xff; 146 pr_debug(" base: %llx, size: %llx, i: %x\n", 147 (unsigned long long)base, 148 (unsigned long long)size, i); 149 150 if (PCI_BASE_ADDRESS_0 <= i && i <= PCI_BASE_ADDRESS_5) { 151 res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2]; 152 } else if (i == dev->rom_base_reg) { 153 res = &dev->resource[PCI_ROM_RESOURCE]; 154 flags |= IORESOURCE_READONLY; 155 } else { 156 printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i); 157 continue; 158 } 159 res->flags = flags; 160 if (mark_unset) 161 res->flags |= IORESOURCE_UNSET; 162 res->name = pci_name(dev); 163 region.start = base; 164 region.end = base + size - 1; 165 pcibios_bus_to_resource(dev->bus, res, ®ion); 166 } 167 } 168 169 /** 170 * of_create_pci_dev - Given a device tree node on a pci bus, create a pci_dev 171 * @node: device tree node pointer 172 * @bus: bus the device is sitting on 173 * @devfn: PCI function number, extracted from device tree by caller. 174 */ 175 struct pci_dev *of_create_pci_dev(struct device_node *node, 176 struct pci_bus *bus, int devfn) 177 { 178 struct pci_dev *dev; 179 180 dev = pci_alloc_dev(bus); 181 if (!dev) 182 return NULL; 183 184 pr_debug(" create device, devfn: %x, type: %s\n", devfn, 185 of_node_get_device_type(node)); 186 187 dev->dev.of_node = of_node_get(node); 188 dev->dev.parent = bus->bridge; 189 dev->dev.bus = &pci_bus_type; 190 dev->devfn = devfn; 191 dev->multifunction = 0; /* maybe a lie? */ 192 dev->needs_freset = 0; /* pcie fundamental reset required */ 193 set_pcie_port_type(dev); 194 195 pci_dev_assign_slot(dev); 196 dev->vendor = get_int_prop(node, "vendor-id", 0xffff); 197 dev->device = get_int_prop(node, "device-id", 0xffff); 198 dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0); 199 dev->subsystem_device = get_int_prop(node, "subsystem-id", 0); 200 201 dev->cfg_size = pci_cfg_space_size(dev); 202 203 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(bus), 204 dev->bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn)); 205 dev->class = get_int_prop(node, "class-code", 0); 206 dev->revision = get_int_prop(node, "revision-id", 0); 207 208 pr_debug(" class: 0x%x\n", dev->class); 209 pr_debug(" revision: 0x%x\n", dev->revision); 210 211 dev->current_state = PCI_UNKNOWN; /* unknown power state */ 212 dev->error_state = pci_channel_io_normal; 213 dev->dma_mask = 0xffffffff; 214 215 /* Early fixups, before probing the BARs */ 216 pci_fixup_device(pci_fixup_early, dev); 217 218 if (of_node_is_type(node, "pci") || of_node_is_type(node, "pciex")) { 219 /* a PCI-PCI bridge */ 220 dev->hdr_type = PCI_HEADER_TYPE_BRIDGE; 221 dev->rom_base_reg = PCI_ROM_ADDRESS1; 222 set_pcie_hotplug_bridge(dev); 223 } else if (of_node_is_type(node, "cardbus")) { 224 dev->hdr_type = PCI_HEADER_TYPE_CARDBUS; 225 } else { 226 dev->hdr_type = PCI_HEADER_TYPE_NORMAL; 227 dev->rom_base_reg = PCI_ROM_ADDRESS; 228 /* Maybe do a default OF mapping here */ 229 dev->irq = 0; 230 } 231 232 of_pci_parse_addrs(node, dev); 233 234 pr_debug(" adding to system ...\n"); 235 236 pci_device_add(dev, bus); 237 238 return dev; 239 } 240 EXPORT_SYMBOL(of_create_pci_dev); 241 242 /** 243 * of_scan_pci_bridge - Set up a PCI bridge and scan for child nodes 244 * @dev: pci_dev structure for the bridge 245 * 246 * of_scan_bus() calls this routine for each PCI bridge that it finds, and 247 * this routine in turn call of_scan_bus() recursively to scan for more child 248 * devices. 249 */ 250 void of_scan_pci_bridge(struct pci_dev *dev) 251 { 252 struct device_node *node = dev->dev.of_node; 253 struct pci_bus *bus; 254 struct pci_controller *phb; 255 const __be32 *busrange, *ranges; 256 int len, i, mode; 257 struct pci_bus_region region; 258 struct resource *res; 259 unsigned int flags; 260 u64 size; 261 262 pr_debug("of_scan_pci_bridge(%pOF)\n", node); 263 264 /* parse bus-range property */ 265 busrange = of_get_property(node, "bus-range", &len); 266 if (busrange == NULL || len != 8) { 267 printk(KERN_DEBUG "Can't get bus-range for PCI-PCI bridge %pOF\n", 268 node); 269 return; 270 } 271 ranges = of_get_property(node, "ranges", &len); 272 if (ranges == NULL) { 273 printk(KERN_DEBUG "Can't get ranges for PCI-PCI bridge %pOF\n", 274 node); 275 return; 276 } 277 278 bus = pci_find_bus(pci_domain_nr(dev->bus), 279 of_read_number(busrange, 1)); 280 if (!bus) { 281 bus = pci_add_new_bus(dev->bus, dev, 282 of_read_number(busrange, 1)); 283 if (!bus) { 284 printk(KERN_ERR "Failed to create pci bus for %pOF\n", 285 node); 286 return; 287 } 288 } 289 290 bus->primary = dev->bus->number; 291 pci_bus_insert_busn_res(bus, of_read_number(busrange, 1), 292 of_read_number(busrange+1, 1)); 293 bus->bridge_ctl = 0; 294 295 /* parse ranges property */ 296 /* PCI #address-cells == 3 and #size-cells == 2 always */ 297 res = &dev->resource[PCI_BRIDGE_RESOURCES]; 298 for (i = 0; i < PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES; ++i) { 299 res->flags = 0; 300 bus->resource[i] = res; 301 ++res; 302 } 303 i = 1; 304 for (; len >= 32; len -= 32, ranges += 8) { 305 flags = pci_parse_of_flags(of_read_number(ranges, 1), 1); 306 size = of_read_number(&ranges[6], 2); 307 if (flags == 0 || size == 0) 308 continue; 309 if (flags & IORESOURCE_IO) { 310 res = bus->resource[0]; 311 if (res->flags) { 312 printk(KERN_ERR "PCI: ignoring extra I/O range" 313 " for bridge %pOF\n", node); 314 continue; 315 } 316 } else { 317 if (i >= PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES) { 318 printk(KERN_ERR "PCI: too many memory ranges" 319 " for bridge %pOF\n", node); 320 continue; 321 } 322 res = bus->resource[i]; 323 ++i; 324 } 325 res->flags = flags; 326 region.start = of_read_number(&ranges[1], 2); 327 region.end = region.start + size - 1; 328 pcibios_bus_to_resource(dev->bus, res, ®ion); 329 } 330 sprintf(bus->name, "PCI Bus %04x:%02x", pci_domain_nr(bus), 331 bus->number); 332 pr_debug(" bus name: %s\n", bus->name); 333 334 phb = pci_bus_to_host(bus); 335 336 mode = PCI_PROBE_NORMAL; 337 if (phb->controller_ops.probe_mode) 338 mode = phb->controller_ops.probe_mode(bus); 339 pr_debug(" probe mode: %d\n", mode); 340 341 if (mode == PCI_PROBE_DEVTREE) 342 of_scan_bus(node, bus); 343 else if (mode == PCI_PROBE_NORMAL) 344 pci_scan_child_bus(bus); 345 } 346 EXPORT_SYMBOL(of_scan_pci_bridge); 347 348 static struct pci_dev *of_scan_pci_dev(struct pci_bus *bus, 349 struct device_node *dn) 350 { 351 struct pci_dev *dev = NULL; 352 const __be32 *reg; 353 int reglen, devfn; 354 #ifdef CONFIG_EEH 355 struct eeh_dev *edev = pdn_to_eeh_dev(PCI_DN(dn)); 356 #endif 357 358 pr_debug(" * %pOF\n", dn); 359 if (!of_device_is_available(dn)) 360 return NULL; 361 362 reg = of_get_property(dn, "reg", ®len); 363 if (reg == NULL || reglen < 20) 364 return NULL; 365 devfn = (of_read_number(reg, 1) >> 8) & 0xff; 366 367 /* Check if the PCI device is already there */ 368 dev = pci_get_slot(bus, devfn); 369 if (dev) { 370 pci_dev_put(dev); 371 return dev; 372 } 373 374 /* Device removed permanently ? */ 375 #ifdef CONFIG_EEH 376 if (edev && (edev->mode & EEH_DEV_REMOVED)) 377 return NULL; 378 #endif 379 380 /* create a new pci_dev for this device */ 381 dev = of_create_pci_dev(dn, bus, devfn); 382 if (!dev) 383 return NULL; 384 385 pr_debug(" dev header type: %x\n", dev->hdr_type); 386 return dev; 387 } 388 389 /** 390 * __of_scan_bus - given a PCI bus node, setup bus and scan for child devices 391 * @node: device tree node for the PCI bus 392 * @bus: pci_bus structure for the PCI bus 393 * @rescan_existing: Flag indicating bus has already been set up 394 */ 395 static void __of_scan_bus(struct device_node *node, struct pci_bus *bus, 396 int rescan_existing) 397 { 398 struct device_node *child; 399 struct pci_dev *dev; 400 401 pr_debug("of_scan_bus(%pOF) bus no %d...\n", 402 node, bus->number); 403 404 /* Scan direct children */ 405 for_each_child_of_node(node, child) { 406 dev = of_scan_pci_dev(bus, child); 407 if (!dev) 408 continue; 409 pr_debug(" dev header type: %x\n", dev->hdr_type); 410 } 411 412 /* Apply all fixups necessary. We don't fixup the bus "self" 413 * for an existing bridge that is being rescanned 414 */ 415 if (!rescan_existing) 416 pcibios_setup_bus_self(bus); 417 418 /* Now scan child busses */ 419 for_each_pci_bridge(dev, bus) 420 of_scan_pci_bridge(dev); 421 } 422 423 /** 424 * of_scan_bus - given a PCI bus node, setup bus and scan for child devices 425 * @node: device tree node for the PCI bus 426 * @bus: pci_bus structure for the PCI bus 427 */ 428 void of_scan_bus(struct device_node *node, struct pci_bus *bus) 429 { 430 __of_scan_bus(node, bus, 0); 431 } 432 EXPORT_SYMBOL_GPL(of_scan_bus); 433 434 /** 435 * of_rescan_bus - given a PCI bus node, scan for child devices 436 * @node: device tree node for the PCI bus 437 * @bus: pci_bus structure for the PCI bus 438 * 439 * Same as of_scan_bus, but for a pci_bus structure that has already been 440 * setup. 441 */ 442 void of_rescan_bus(struct device_node *node, struct pci_bus *bus) 443 { 444 __of_scan_bus(node, bus, 1); 445 } 446 EXPORT_SYMBOL_GPL(of_rescan_bus); 447 448