1 /* 2 * Helper routines to scan the device tree for PCI devices and busses 3 * 4 * Migrated out of PowerPC architecture pci_64.c file by Grant Likely 5 * <grant.likely@secretlab.ca> so that these routines are available for 6 * 32 bit also. 7 * 8 * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM 9 * Rework, based on alpha PCI code. 10 * Copyright (c) 2009 Secret Lab Technologies Ltd. 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License 14 * version 2 as published by the Free Software Foundation. 15 */ 16 17 #include <linux/pci.h> 18 #include <asm/pci-bridge.h> 19 #include <asm/prom.h> 20 21 /** 22 * get_int_prop - Decode a u32 from a device tree property 23 */ 24 static u32 get_int_prop(struct device_node *np, const char *name, u32 def) 25 { 26 const u32 *prop; 27 int len; 28 29 prop = of_get_property(np, name, &len); 30 if (prop && len >= 4) 31 return *prop; 32 return def; 33 } 34 35 /** 36 * pci_parse_of_flags - Parse the flags cell of a device tree PCI address 37 * @addr0: value of 1st cell of a device tree PCI address. 38 * @bridge: Set this flag if the address is from a bridge 'ranges' property 39 */ 40 unsigned int pci_parse_of_flags(u32 addr0, int bridge) 41 { 42 unsigned int flags = 0; 43 44 if (addr0 & 0x02000000) { 45 flags = IORESOURCE_MEM | PCI_BASE_ADDRESS_SPACE_MEMORY; 46 flags |= (addr0 >> 22) & PCI_BASE_ADDRESS_MEM_TYPE_64; 47 flags |= (addr0 >> 28) & PCI_BASE_ADDRESS_MEM_TYPE_1M; 48 if (addr0 & 0x40000000) 49 flags |= IORESOURCE_PREFETCH 50 | PCI_BASE_ADDRESS_MEM_PREFETCH; 51 /* Note: We don't know whether the ROM has been left enabled 52 * by the firmware or not. We mark it as disabled (ie, we do 53 * not set the IORESOURCE_ROM_ENABLE flag) for now rather than 54 * do a config space read, it will be force-enabled if needed 55 */ 56 if (!bridge && (addr0 & 0xff) == 0x30) 57 flags |= IORESOURCE_READONLY; 58 } else if (addr0 & 0x01000000) 59 flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO; 60 if (flags) 61 flags |= IORESOURCE_SIZEALIGN; 62 return flags; 63 } 64 65 /** 66 * of_pci_parse_addrs - Parse PCI addresses assigned in the device tree node 67 * @node: device tree node for the PCI device 68 * @dev: pci_dev structure for the device 69 * 70 * This function parses the 'assigned-addresses' property of a PCI devices' 71 * device tree node and writes them into the associated pci_dev structure. 72 */ 73 static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev) 74 { 75 u64 base, size; 76 unsigned int flags; 77 struct resource *res; 78 const u32 *addrs; 79 u32 i; 80 int proplen; 81 82 addrs = of_get_property(node, "assigned-addresses", &proplen); 83 if (!addrs) 84 return; 85 pr_debug(" parse addresses (%d bytes) @ %p\n", proplen, addrs); 86 for (; proplen >= 20; proplen -= 20, addrs += 5) { 87 flags = pci_parse_of_flags(addrs[0], 0); 88 if (!flags) 89 continue; 90 base = of_read_number(&addrs[1], 2); 91 size = of_read_number(&addrs[3], 2); 92 if (!size) 93 continue; 94 i = addrs[0] & 0xff; 95 pr_debug(" base: %llx, size: %llx, i: %x\n", 96 (unsigned long long)base, 97 (unsigned long long)size, i); 98 99 if (PCI_BASE_ADDRESS_0 <= i && i <= PCI_BASE_ADDRESS_5) { 100 res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2]; 101 } else if (i == dev->rom_base_reg) { 102 res = &dev->resource[PCI_ROM_RESOURCE]; 103 flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE; 104 } else { 105 printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i); 106 continue; 107 } 108 res->start = base; 109 res->end = base + size - 1; 110 res->flags = flags; 111 res->name = pci_name(dev); 112 } 113 } 114 115 /** 116 * of_create_pci_dev - Given a device tree node on a pci bus, create a pci_dev 117 * @node: device tree node pointer 118 * @bus: bus the device is sitting on 119 * @devfn: PCI function number, extracted from device tree by caller. 120 */ 121 struct pci_dev *of_create_pci_dev(struct device_node *node, 122 struct pci_bus *bus, int devfn) 123 { 124 struct pci_dev *dev; 125 const char *type; 126 struct pci_slot *slot; 127 128 dev = alloc_pci_dev(); 129 if (!dev) 130 return NULL; 131 type = of_get_property(node, "device_type", NULL); 132 if (type == NULL) 133 type = ""; 134 135 pr_debug(" create device, devfn: %x, type: %s\n", devfn, type); 136 137 dev->bus = bus; 138 dev->dev.of_node = of_node_get(node); 139 dev->dev.parent = bus->bridge; 140 dev->dev.bus = &pci_bus_type; 141 dev->devfn = devfn; 142 dev->multifunction = 0; /* maybe a lie? */ 143 dev->needs_freset = 0; /* pcie fundamental reset required */ 144 set_pcie_port_type(dev); 145 146 list_for_each_entry(slot, &dev->bus->slots, list) 147 if (PCI_SLOT(dev->devfn) == slot->number) 148 dev->slot = slot; 149 150 dev->vendor = get_int_prop(node, "vendor-id", 0xffff); 151 dev->device = get_int_prop(node, "device-id", 0xffff); 152 dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0); 153 dev->subsystem_device = get_int_prop(node, "subsystem-id", 0); 154 155 dev->cfg_size = pci_cfg_space_size(dev); 156 157 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(bus), 158 dev->bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn)); 159 dev->class = get_int_prop(node, "class-code", 0); 160 dev->revision = get_int_prop(node, "revision-id", 0); 161 162 pr_debug(" class: 0x%x\n", dev->class); 163 pr_debug(" revision: 0x%x\n", dev->revision); 164 165 dev->current_state = 4; /* unknown power state */ 166 dev->error_state = pci_channel_io_normal; 167 dev->dma_mask = 0xffffffff; 168 169 /* Early fixups, before probing the BARs */ 170 pci_fixup_device(pci_fixup_early, dev); 171 172 if (!strcmp(type, "pci") || !strcmp(type, "pciex")) { 173 /* a PCI-PCI bridge */ 174 dev->hdr_type = PCI_HEADER_TYPE_BRIDGE; 175 dev->rom_base_reg = PCI_ROM_ADDRESS1; 176 set_pcie_hotplug_bridge(dev); 177 } else if (!strcmp(type, "cardbus")) { 178 dev->hdr_type = PCI_HEADER_TYPE_CARDBUS; 179 } else { 180 dev->hdr_type = PCI_HEADER_TYPE_NORMAL; 181 dev->rom_base_reg = PCI_ROM_ADDRESS; 182 /* Maybe do a default OF mapping here */ 183 dev->irq = NO_IRQ; 184 } 185 186 of_pci_parse_addrs(node, dev); 187 188 pr_debug(" adding to system ...\n"); 189 190 pci_device_add(dev, bus); 191 192 return dev; 193 } 194 EXPORT_SYMBOL(of_create_pci_dev); 195 196 /** 197 * of_scan_pci_bridge - Set up a PCI bridge and scan for child nodes 198 * @node: device tree node of bridge 199 * @dev: pci_dev structure for the bridge 200 * 201 * of_scan_bus() calls this routine for each PCI bridge that it finds, and 202 * this routine in turn call of_scan_bus() recusively to scan for more child 203 * devices. 204 */ 205 void __devinit of_scan_pci_bridge(struct pci_dev *dev) 206 { 207 struct device_node *node = dev->dev.of_node; 208 struct pci_bus *bus; 209 const u32 *busrange, *ranges; 210 int len, i, mode; 211 struct resource *res; 212 unsigned int flags; 213 u64 size; 214 215 pr_debug("of_scan_pci_bridge(%s)\n", node->full_name); 216 217 /* parse bus-range property */ 218 busrange = of_get_property(node, "bus-range", &len); 219 if (busrange == NULL || len != 8) { 220 printk(KERN_DEBUG "Can't get bus-range for PCI-PCI bridge %s\n", 221 node->full_name); 222 return; 223 } 224 ranges = of_get_property(node, "ranges", &len); 225 if (ranges == NULL) { 226 printk(KERN_DEBUG "Can't get ranges for PCI-PCI bridge %s\n", 227 node->full_name); 228 return; 229 } 230 231 bus = pci_add_new_bus(dev->bus, dev, busrange[0]); 232 if (!bus) { 233 printk(KERN_ERR "Failed to create pci bus for %s\n", 234 node->full_name); 235 return; 236 } 237 238 bus->primary = dev->bus->number; 239 bus->subordinate = busrange[1]; 240 bus->bridge_ctl = 0; 241 242 /* parse ranges property */ 243 /* PCI #address-cells == 3 and #size-cells == 2 always */ 244 res = &dev->resource[PCI_BRIDGE_RESOURCES]; 245 for (i = 0; i < PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES; ++i) { 246 res->flags = 0; 247 bus->resource[i] = res; 248 ++res; 249 } 250 i = 1; 251 for (; len >= 32; len -= 32, ranges += 8) { 252 flags = pci_parse_of_flags(ranges[0], 1); 253 size = of_read_number(&ranges[6], 2); 254 if (flags == 0 || size == 0) 255 continue; 256 if (flags & IORESOURCE_IO) { 257 res = bus->resource[0]; 258 if (res->flags) { 259 printk(KERN_ERR "PCI: ignoring extra I/O range" 260 " for bridge %s\n", node->full_name); 261 continue; 262 } 263 } else { 264 if (i >= PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES) { 265 printk(KERN_ERR "PCI: too many memory ranges" 266 " for bridge %s\n", node->full_name); 267 continue; 268 } 269 res = bus->resource[i]; 270 ++i; 271 } 272 res->start = of_read_number(&ranges[1], 2); 273 res->end = res->start + size - 1; 274 res->flags = flags; 275 } 276 sprintf(bus->name, "PCI Bus %04x:%02x", pci_domain_nr(bus), 277 bus->number); 278 pr_debug(" bus name: %s\n", bus->name); 279 280 mode = PCI_PROBE_NORMAL; 281 if (ppc_md.pci_probe_mode) 282 mode = ppc_md.pci_probe_mode(bus); 283 pr_debug(" probe mode: %d\n", mode); 284 285 if (mode == PCI_PROBE_DEVTREE) 286 of_scan_bus(node, bus); 287 else if (mode == PCI_PROBE_NORMAL) 288 pci_scan_child_bus(bus); 289 } 290 EXPORT_SYMBOL(of_scan_pci_bridge); 291 292 /** 293 * __of_scan_bus - given a PCI bus node, setup bus and scan for child devices 294 * @node: device tree node for the PCI bus 295 * @bus: pci_bus structure for the PCI bus 296 * @rescan_existing: Flag indicating bus has already been set up 297 */ 298 static void __devinit __of_scan_bus(struct device_node *node, 299 struct pci_bus *bus, int rescan_existing) 300 { 301 struct device_node *child; 302 const u32 *reg; 303 int reglen, devfn; 304 struct pci_dev *dev; 305 306 pr_debug("of_scan_bus(%s) bus no %d...\n", 307 node->full_name, bus->number); 308 309 /* Scan direct children */ 310 for_each_child_of_node(node, child) { 311 pr_debug(" * %s\n", child->full_name); 312 if (!of_device_is_available(child)) 313 continue; 314 reg = of_get_property(child, "reg", ®len); 315 if (reg == NULL || reglen < 20) 316 continue; 317 devfn = (reg[0] >> 8) & 0xff; 318 319 /* create a new pci_dev for this device */ 320 dev = of_create_pci_dev(child, bus, devfn); 321 if (!dev) 322 continue; 323 pr_debug(" dev header type: %x\n", dev->hdr_type); 324 } 325 326 /* Apply all fixups necessary. We don't fixup the bus "self" 327 * for an existing bridge that is being rescanned 328 */ 329 if (!rescan_existing) 330 pcibios_setup_bus_self(bus); 331 pcibios_setup_bus_devices(bus); 332 333 /* Now scan child busses */ 334 list_for_each_entry(dev, &bus->devices, bus_list) { 335 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE || 336 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) { 337 of_scan_pci_bridge(dev); 338 } 339 } 340 } 341 342 /** 343 * of_scan_bus - given a PCI bus node, setup bus and scan for child devices 344 * @node: device tree node for the PCI bus 345 * @bus: pci_bus structure for the PCI bus 346 */ 347 void __devinit of_scan_bus(struct device_node *node, 348 struct pci_bus *bus) 349 { 350 __of_scan_bus(node, bus, 0); 351 } 352 EXPORT_SYMBOL_GPL(of_scan_bus); 353 354 /** 355 * of_rescan_bus - given a PCI bus node, scan for child devices 356 * @node: device tree node for the PCI bus 357 * @bus: pci_bus structure for the PCI bus 358 * 359 * Same as of_scan_bus, but for a pci_bus structure that has already been 360 * setup. 361 */ 362 void __devinit of_rescan_bus(struct device_node *node, 363 struct pci_bus *bus) 364 { 365 __of_scan_bus(node, bus, 1); 366 } 367 EXPORT_SYMBOL_GPL(of_rescan_bus); 368 369