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 <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
 127         dev = alloc_pci_dev();
 128         if (!dev)
 129                 return NULL;
 130         type = of_get_property(node, "device_type", NULL);
 131         if (type == NULL)
 132                 type = "";
 133
 134         pr_debug("    create device, devfn: %x, type: %s\n", devfn, type);
 135
 136         dev->bus = bus;
 137         dev->sysdata = node;
 138         dev->dev.parent = bus->bridge;
 139         dev->dev.bus = &pci_bus_type;
 140         dev->devfn = devfn;
 141         dev->multifunction = 0;         /* maybe a lie? */
 142         dev->needs_freset = 0;          /* pcie fundamental reset required */
 143
 144         dev->vendor = get_int_prop(node, "vendor-id", 0xffff);
 145         dev->device = get_int_prop(node, "device-id", 0xffff);
 146         dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0);
 147         dev->subsystem_device = get_int_prop(node, "subsystem-id", 0);
 148
 149         dev->cfg_size = pci_cfg_space_size(dev);
 150
 151         dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(bus),
 152                 dev->bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn));
 153         dev->class = get_int_prop(node, "class-code", 0);
 154         dev->revision = get_int_prop(node, "revision-id", 0);
 155
 156         pr_debug("    class: 0x%x\n", dev->class);
 157         pr_debug("    revision: 0x%x\n", dev->revision);
 158
 159         dev->current_state = 4;         /* unknown power state */
 160         dev->error_state = pci_channel_io_normal;
 161         dev->dma_mask = 0xffffffff;
 162
 163         if (!strcmp(type, "pci") || !strcmp(type, "pciex")) {
 164                 /* a PCI-PCI bridge */
 165                 dev->hdr_type = PCI_HEADER_TYPE_BRIDGE;
 166                 dev->rom_base_reg = PCI_ROM_ADDRESS1;
 167         } else if (!strcmp(type, "cardbus")) {
 168                 dev->hdr_type = PCI_HEADER_TYPE_CARDBUS;
 169         } else {
 170                 dev->hdr_type = PCI_HEADER_TYPE_NORMAL;
 171                 dev->rom_base_reg = PCI_ROM_ADDRESS;
 172                 /* Maybe do a default OF mapping here */
 173                 dev->irq = NO_IRQ;
 174         }
 175
 176         of_pci_parse_addrs(node, dev);
 177
 178         pr_debug("    adding to system ...\n");
 179
 180         pci_device_add(dev, bus);
 181
 182         return dev;
 183 }
 184 EXPORT_SYMBOL(of_create_pci_dev);
 185
 186 /**
 187  * of_scan_pci_bridge - Set up a PCI bridge and scan for child nodes
 188  * @node: device tree node of bridge
 189  * @dev: pci_dev structure for the bridge
 190  *
 191  * of_scan_bus() calls this routine for each PCI bridge that it finds, and
 192  * this routine in turn call of_scan_bus() recusively to scan for more child
 193  * devices.
 194  */
 195 void __devinit of_scan_pci_bridge(struct device_node *node,
 196                                   struct pci_dev *dev)
 197 {
 198         struct pci_bus *bus;
 199         const u32 *busrange, *ranges;
 200         int len, i, mode;
 201         struct resource *res;
 202         unsigned int flags;
 203         u64 size;
 204
 205         pr_debug("of_scan_pci_bridge(%s)\n", node->full_name);
 206
 207         /* parse bus-range property */
 208         busrange = of_get_property(node, "bus-range", &len);
 209         if (busrange == NULL || len != 8) {
 210                 printk(KERN_DEBUG "Can't get bus-range for PCI-PCI bridge %s\n",
 211                        node->full_name);
 212                 return;
 213         }
 214         ranges = of_get_property(node, "ranges", &len);
 215         if (ranges == NULL) {
 216                 printk(KERN_DEBUG "Can't get ranges for PCI-PCI bridge %s\n",
 217                        node->full_name);
 218                 return;
 219         }
 220
 221         bus = pci_add_new_bus(dev->bus, dev, busrange[0]);
 222         if (!bus) {
 223                 printk(KERN_ERR "Failed to create pci bus for %s\n",
 224                        node->full_name);
 225                 return;
 226         }
 227
 228         bus->primary = dev->bus->number;
 229         bus->subordinate = busrange[1];
 230         bus->bridge_ctl = 0;
 231         bus->sysdata = node;
 232
 233         /* parse ranges property */
 234         /* PCI #address-cells == 3 and #size-cells == 2 always */
 235         res = &dev->resource[PCI_BRIDGE_RESOURCES];
 236         for (i = 0; i < PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES; ++i) {
 237                 res->flags = 0;
 238                 bus->resource[i] = res;
 239                 ++res;
 240         }
 241         i = 1;
 242         for (; len >= 32; len -= 32, ranges += 8) {
 243                 flags = pci_parse_of_flags(ranges[0], 1);
 244                 size = of_read_number(&ranges[6], 2);
 245                 if (flags == 0 || size == 0)
 246                         continue;
 247                 if (flags & IORESOURCE_IO) {
 248                         res = bus->resource[0];
 249                         if (res->flags) {
 250                                 printk(KERN_ERR "PCI: ignoring extra I/O range"
 251                                        " for bridge %s\n", node->full_name);
 252                                 continue;
 253                         }
 254                 } else {
 255                         if (i >= PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES) {
 256                                 printk(KERN_ERR "PCI: too many memory ranges"
 257                                        " for bridge %s\n", node->full_name);
 258                                 continue;
 259                         }
 260                         res = bus->resource[i];
 261                         ++i;
 262                 }
 263                 res->start = of_read_number(&ranges[1], 2);
 264                 res->end = res->start + size - 1;
 265                 res->flags = flags;
 266         }
 267         sprintf(bus->name, "PCI Bus %04x:%02x", pci_domain_nr(bus),
 268                 bus->number);
 269         pr_debug("    bus name: %s\n", bus->name);
 270
 271         mode = PCI_PROBE_NORMAL;
 272         if (ppc_md.pci_probe_mode)
 273                 mode = ppc_md.pci_probe_mode(bus);
 274         pr_debug("    probe mode: %d\n", mode);
 275
 276         if (mode == PCI_PROBE_DEVTREE)
 277                 of_scan_bus(node, bus);
 278         else if (mode == PCI_PROBE_NORMAL)
 279                 pci_scan_child_bus(bus);
 280 }
 281 EXPORT_SYMBOL(of_scan_pci_bridge);
 282
 283 /**
 284  * __of_scan_bus - given a PCI bus node, setup bus and scan for child devices
 285  * @node: device tree node for the PCI bus
 286  * @bus: pci_bus structure for the PCI bus
 287  * @rescan_existing: Flag indicating bus has already been set up
 288  */
 289 static void __devinit __of_scan_bus(struct device_node *node,
 290                                     struct pci_bus *bus, int rescan_existing)
 291 {
 292         struct device_node *child;
 293         const u32 *reg;
 294         int reglen, devfn;
 295         struct pci_dev *dev;
 296
 297         pr_debug("of_scan_bus(%s) bus no %d... \n",
 298                  node->full_name, bus->number);
 299
 300         /* Scan direct children */
 301         for_each_child_of_node(node, child) {
 302                 pr_debug("  * %s\n", child->full_name);
 303                 reg = of_get_property(child, "reg", &reglen);
 304                 if (reg == NULL || reglen < 20)
 305                         continue;
 306                 devfn = (reg[0] >> 8) & 0xff;
 307
 308                 /* create a new pci_dev for this device */
 309                 dev = of_create_pci_dev(child, bus, devfn);
 310                 if (!dev)
 311                         continue;
 312                 pr_debug("    dev header type: %x\n", dev->hdr_type);
 313         }
 314
 315         /* Apply all fixups necessary. We don't fixup the bus "self"
 316          * for an existing bridge that is being rescanned
 317          */
 318         if (!rescan_existing)
 319                 pcibios_setup_bus_self(bus);
 320         pcibios_setup_bus_devices(bus);
 321
 322         /* Now scan child busses */
 323         list_for_each_entry(dev, &bus->devices, bus_list) {
 324                 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
 325                     dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
 326                         struct device_node *child = pci_device_to_OF_node(dev);
 327                         if (dev)
 328                                 of_scan_pci_bridge(child, dev);
 329                 }
 330         }
 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  */
 338 void __devinit of_scan_bus(struct device_node *node,
 339                            struct pci_bus *bus)
 340 {
 341         __of_scan_bus(node, bus, 0);
 342 }
 343 EXPORT_SYMBOL_GPL(of_scan_bus);
 344
 345 /**
 346  * of_rescan_bus - given a PCI bus node, scan for child devices
 347  * @node: device tree node for the PCI bus
 348  * @bus: pci_bus structure for the PCI bus
 349  *
 350  * Same as of_scan_bus, but for a pci_bus structure that has already been
 351  * setup.
 352  */
 353 void __devinit of_rescan_bus(struct device_node *node,
 354                              struct pci_bus *bus)
 355 {
 356         __of_scan_bus(node, bus, 1);
 357 }
 358 EXPORT_SYMBOL_GPL(of_rescan_bus);
 359