arch/powerpc/kernel/pci_of_scan.c

   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 <linux/export.h>
  19 #include <asm/pci-bridge.h>
  20 #include <asm/prom.h>
  21
  22 /**
  23  * get_int_prop - Decode a u32 from a device tree property
  24  */
  25 static u32 get_int_prop(struct device_node *np, const char *name, u32 def)
  26 {
  27         const __be32 *prop;
  28         int len;
  29
  30         prop = of_get_property(np, name, &len);
  31         if (prop && len >= 4)
  32                 return of_read_number(prop, 1);
  33         return def;
  34 }
  35
  36 /**
  37  * pci_parse_of_flags - Parse the flags cell of a device tree PCI address
  38  * @addr0: value of 1st cell of a device tree PCI address.
  39  * @bridge: Set this flag if the address is from a bridge 'ranges' property
  40  */
  41 unsigned int pci_parse_of_flags(u32 addr0, int bridge)
  42 {
  43         unsigned int flags = 0;
  44
  45         if (addr0 & 0x02000000) {
  46                 flags = IORESOURCE_MEM | PCI_BASE_ADDRESS_SPACE_MEMORY;
  47                 flags |= (addr0 >> 22) & PCI_BASE_ADDRESS_MEM_TYPE_64;
  48                 flags |= (addr0 >> 28) & PCI_BASE_ADDRESS_MEM_TYPE_1M;
  49                 if (addr0 & 0x40000000)
  50                         flags |= IORESOURCE_PREFETCH
  51                                  | PCI_BASE_ADDRESS_MEM_PREFETCH;
  52                 /* Note: We don't know whether the ROM has been left enabled
  53                  * by the firmware or not. We mark it as disabled (ie, we do
  54                  * not set the IORESOURCE_ROM_ENABLE flag) for now rather than
  55                  * do a config space read, it will be force-enabled if needed
  56                  */
  57                 if (!bridge && (addr0 & 0xff) == 0x30)
  58                         flags |= IORESOURCE_READONLY;
  59         } else if (addr0 & 0x01000000)
  60                 flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO;
  61         if (flags)
  62                 flags |= IORESOURCE_SIZEALIGN;
  63         return flags;
  64 }
  65
  66 /**
  67  * of_pci_parse_addrs - Parse PCI addresses assigned in the device tree node
  68  * @node: device tree node for the PCI device
  69  * @dev: pci_dev structure for the device
  70  *
  71  * This function parses the 'assigned-addresses' property of a PCI devices'
  72  * device tree node and writes them into the associated pci_dev structure.
  73  */
  74 static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev)
  75 {
  76         u64 base, size;
  77         unsigned int flags;
  78         struct pci_bus_region region;
  79         struct resource *res;
  80         const __be32 *addrs;
  81         u32 i;
  82         int proplen;
  83
  84         addrs = of_get_property(node, "assigned-addresses", &proplen);
  85         if (!addrs)
  86                 return;
  87         pr_debug("    parse addresses (%d bytes) @ %p\n", proplen, addrs);
  88         for (; proplen >= 20; proplen -= 20, addrs += 5) {
  89                 flags = pci_parse_of_flags(of_read_number(addrs, 1), 0);
  90                 if (!flags)
  91                         continue;
  92                 base = of_read_number(&addrs[1], 2);
  93                 size = of_read_number(&addrs[3], 2);
  94                 if (!size)
  95                         continue;
  96                 i = of_read_number(addrs, 1) & 0xff;
  97                 pr_debug("  base: %llx, size: %llx, i: %x\n",
  98                          (unsigned long long)base,
  99                          (unsigned long long)size, i);
 100
 101                 if (PCI_BASE_ADDRESS_0 <= i && i <= PCI_BASE_ADDRESS_5) {
 102                         res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
 103                 } else if (i == dev->rom_base_reg) {
 104                         res = &dev->resource[PCI_ROM_RESOURCE];
 105                         flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE;
 106                 } else {
 107                         printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
 108                         continue;
 109                 }
 110                 res->flags = flags;
 111                 res->name = pci_name(dev);
 112                 region.start = base;
 113                 region.end = base + size - 1;
 114                 pcibios_bus_to_resource(dev->bus, res, &region);
 115         }
 116 }
 117
 118 /**
 119  * of_create_pci_dev - Given a device tree node on a pci bus, create a pci_dev
 120  * @node: device tree node pointer
 121  * @bus: bus the device is sitting on
 122  * @devfn: PCI function number, extracted from device tree by caller.
 123  */
 124 struct pci_dev *of_create_pci_dev(struct device_node *node,
 125                                  struct pci_bus *bus, int devfn)
 126 {
 127         struct pci_dev *dev;
 128         const char *type;
 129         struct pci_slot *slot;
 130
 131         dev = pci_alloc_dev(bus);
 132         if (!dev)
 133                 return NULL;
 134         type = of_get_property(node, "device_type", NULL);
 135         if (type == NULL)
 136                 type = "";
 137
 138         pr_debug("    create device, devfn: %x, type: %s\n", devfn, type);
 139
 140         dev->dev.of_node = of_node_get(node);
 141         dev->dev.parent = bus->bridge;
 142         dev->dev.bus = &pci_bus_type;
 143         dev->devfn = devfn;
 144         dev->multifunction = 0;         /* maybe a lie? */
 145         dev->needs_freset = 0;          /* pcie fundamental reset required */
 146         set_pcie_port_type(dev);
 147
 148         list_for_each_entry(slot, &dev->bus->slots, list)
 149                 if (PCI_SLOT(dev->devfn) == slot->number)
 150                         dev->slot = slot;
 151
 152         dev->vendor = get_int_prop(node, "vendor-id", 0xffff);
 153         dev->device = get_int_prop(node, "device-id", 0xffff);
 154         dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0);
 155         dev->subsystem_device = get_int_prop(node, "subsystem-id", 0);
 156
 157         dev->cfg_size = pci_cfg_space_size(dev);
 158
 159         dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(bus),
 160                 dev->bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn));
 161         dev->class = get_int_prop(node, "class-code", 0);
 162         dev->revision = get_int_prop(node, "revision-id", 0);
 163
 164         pr_debug("    class: 0x%x\n", dev->class);
 165         pr_debug("    revision: 0x%x\n", dev->revision);
 166
 167         dev->current_state = PCI_UNKNOWN;       /* unknown power state */
 168         dev->error_state = pci_channel_io_normal;
 169         dev->dma_mask = 0xffffffff;
 170
 171         /* Early fixups, before probing the BARs */
 172         pci_fixup_device(pci_fixup_early, dev);
 173
 174         if (!strcmp(type, "pci") || !strcmp(type, "pciex")) {
 175                 /* a PCI-PCI bridge */
 176                 dev->hdr_type = PCI_HEADER_TYPE_BRIDGE;
 177                 dev->rom_base_reg = PCI_ROM_ADDRESS1;
 178                 set_pcie_hotplug_bridge(dev);
 179         } else if (!strcmp(type, "cardbus")) {
 180                 dev->hdr_type = PCI_HEADER_TYPE_CARDBUS;
 181         } else {
 182                 dev->hdr_type = PCI_HEADER_TYPE_NORMAL;
 183                 dev->rom_base_reg = PCI_ROM_ADDRESS;
 184                 /* Maybe do a default OF mapping here */
 185                 dev->irq = NO_IRQ;
 186         }
 187
 188         of_pci_parse_addrs(node, dev);
 189
 190         pr_debug("    adding to system ...\n");
 191
 192         pci_device_add(dev, bus);
 193
 194         return dev;
 195 }
 196 EXPORT_SYMBOL(of_create_pci_dev);
 197
 198 /**
 199  * of_scan_pci_bridge - Set up a PCI bridge and scan for child nodes
 200  * @dev: pci_dev structure for the bridge
 201  *
 202  * of_scan_bus() calls this routine for each PCI bridge that it finds, and
 203  * this routine in turn call of_scan_bus() recusively to scan for more child
 204  * devices.
 205  */
 206 void of_scan_pci_bridge(struct pci_dev *dev)
 207 {
 208         struct device_node *node = dev->dev.of_node;
 209         struct pci_bus *bus;
 210         const __be32 *busrange, *ranges;
 211         int len, i, mode;
 212         struct pci_bus_region region;
 213         struct resource *res;
 214         unsigned int flags;
 215         u64 size;
 216
 217         pr_debug("of_scan_pci_bridge(%s)\n", node->full_name);
 218
 219         /* parse bus-range property */
 220         busrange = of_get_property(node, "bus-range", &len);
 221         if (busrange == NULL || len != 8) {
 222                 printk(KERN_DEBUG "Can't get bus-range for PCI-PCI bridge %s\n",
 223                        node->full_name);
 224                 return;
 225         }
 226         ranges = of_get_property(node, "ranges", &len);
 227         if (ranges == NULL) {
 228                 printk(KERN_DEBUG "Can't get ranges for PCI-PCI bridge %s\n",
 229                        node->full_name);
 230                 return;
 231         }
 232
 233         bus = pci_find_bus(pci_domain_nr(dev->bus),
 234                            of_read_number(busrange, 1));
 235         if (!bus) {
 236                 bus = pci_add_new_bus(dev->bus, dev,
 237                                       of_read_number(busrange, 1));
 238                 if (!bus) {
 239                         printk(KERN_ERR "Failed to create pci bus for %s\n",
 240                                node->full_name);
 241                         return;
 242                 }
 243         }
 244
 245         bus->primary = dev->bus->number;
 246         pci_bus_insert_busn_res(bus, of_read_number(busrange, 1),
 247                                 of_read_number(busrange+1, 1));
 248         bus->bridge_ctl = 0;
 249
 250         /* parse ranges property */
 251         /* PCI #address-cells == 3 and #size-cells == 2 always */
 252         res = &dev->resource[PCI_BRIDGE_RESOURCES];
 253         for (i = 0; i < PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES; ++i) {
 254                 res->flags = 0;
 255                 bus->resource[i] = res;
 256                 ++res;
 257         }
 258         i = 1;
 259         for (; len >= 32; len -= 32, ranges += 8) {
 260                 flags = pci_parse_of_flags(of_read_number(ranges, 1), 1);
 261                 size = of_read_number(&ranges[6], 2);
 262                 if (flags == 0 || size == 0)
 263                         continue;
 264                 if (flags & IORESOURCE_IO) {
 265                         res = bus->resource[0];
 266                         if (res->flags) {
 267                                 printk(KERN_ERR "PCI: ignoring extra I/O range"
 268                                        " for bridge %s\n", node->full_name);
 269                                 continue;
 270                         }
 271                 } else {
 272                         if (i >= PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES) {
 273                                 printk(KERN_ERR "PCI: too many memory ranges"
 274                                        " for bridge %s\n", node->full_name);
 275                                 continue;
 276                         }
 277                         res = bus->resource[i];
 278                         ++i;
 279                 }
 280                 res->flags = flags;
 281                 region.start = of_read_number(&ranges[1], 2);
 282                 region.end = region.start + size - 1;
 283                 pcibios_bus_to_resource(dev->bus, res, &region);
 284         }
 285         sprintf(bus->name, "PCI Bus %04x:%02x", pci_domain_nr(bus),
 286                 bus->number);
 287         pr_debug("    bus name: %s\n", bus->name);
 288
 289         mode = PCI_PROBE_NORMAL;
 290         if (ppc_md.pci_probe_mode)
 291                 mode = ppc_md.pci_probe_mode(bus);
 292         pr_debug("    probe mode: %d\n", mode);
 293
 294         if (mode == PCI_PROBE_DEVTREE)
 295                 of_scan_bus(node, bus);
 296         else if (mode == PCI_PROBE_NORMAL)
 297                 pci_scan_child_bus(bus);
 298 }
 299 EXPORT_SYMBOL(of_scan_pci_bridge);
 300
 301 static struct pci_dev *of_scan_pci_dev(struct pci_bus *bus,
 302                             struct device_node *dn)
 303 {
 304         struct pci_dev *dev = NULL;
 305         const __be32 *reg;
 306         int reglen, devfn;
 307
 308         pr_debug("  * %s\n", dn->full_name);
 309         if (!of_device_is_available(dn))
 310                 return NULL;
 311
 312         reg = of_get_property(dn, "reg", &reglen);
 313         if (reg == NULL || reglen < 20)
 314                 return NULL;
 315         devfn = (of_read_number(reg, 1) >> 8) & 0xff;
 316
 317         /* Check if the PCI device is already there */
 318         dev = pci_get_slot(bus, devfn);
 319         if (dev) {
 320                 pci_dev_put(dev);
 321                 return dev;
 322         }
 323
 324         /* create a new pci_dev for this device */
 325         dev = of_create_pci_dev(dn, bus, devfn);
 326         if (!dev)
 327                 return NULL;
 328
 329         pr_debug("  dev header type: %x\n", dev->hdr_type);
 330         return dev;
 331 }
 332
 333 /**
 334  * __of_scan_bus - given a PCI bus node, setup bus and scan for child devices
 335  * @node: device tree node for the PCI bus
 336  * @bus: pci_bus structure for the PCI bus
 337  * @rescan_existing: Flag indicating bus has already been set up
 338  */
 339 static void __of_scan_bus(struct device_node *node, struct pci_bus *bus,
 340                           int rescan_existing)
 341 {
 342         struct device_node *child;
 343         struct pci_dev *dev;
 344
 345         pr_debug("of_scan_bus(%s) bus no %d...\n",
 346                  node->full_name, bus->number);
 347
 348         /* Scan direct children */
 349         for_each_child_of_node(node, child) {
 350                 dev = of_scan_pci_dev(bus, child);
 351                 if (!dev)
 352                         continue;
 353                 pr_debug("    dev header type: %x\n", dev->hdr_type);
 354         }
 355
 356         /* Apply all fixups necessary. We don't fixup the bus "self"
 357          * for an existing bridge that is being rescanned
 358          */
 359         if (!rescan_existing)
 360                 pcibios_setup_bus_self(bus);
 361         pcibios_setup_bus_devices(bus);
 362
 363         /* Now scan child busses */
 364         list_for_each_entry(dev, &bus->devices, bus_list) {
 365                 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
 366                     dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
 367                         of_scan_pci_bridge(dev);
 368                 }
 369         }
 370 }
 371
 372 /**
 373  * of_scan_bus - given a PCI bus node, setup bus and scan for child devices
 374  * @node: device tree node for the PCI bus
 375  * @bus: pci_bus structure for the PCI bus
 376  */
 377 void of_scan_bus(struct device_node *node, struct pci_bus *bus)
 378 {
 379         __of_scan_bus(node, bus, 0);
 380 }
 381 EXPORT_SYMBOL_GPL(of_scan_bus);
 382
 383 /**
 384  * of_rescan_bus - given a PCI bus node, scan for child devices
 385  * @node: device tree node for the PCI bus
 386  * @bus: pci_bus structure for the PCI bus
 387  *
 388  * Same as of_scan_bus, but for a pci_bus structure that has already been
 389  * setup.
 390  */
 391 void of_rescan_bus(struct device_node *node, struct pci_bus *bus)
 392 {
 393         __of_scan_bus(node, bus, 1);
 394 }
 395 EXPORT_SYMBOL_GPL(of_rescan_bus);
 396