arch/powerpc/kernel/pci_dn.c

   1 /*
   2  * pci_dn.c
   3  *
   4  * Copyright (C) 2001 Todd Inglett, IBM Corporation
   5  *
   6  * PCI manipulation via device_nodes.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  21  */
  22 #include <linux/kernel.h>
  23 #include <linux/pci.h>
  24 #include <linux/string.h>
  25 #include <linux/export.h>
  26 #include <linux/init.h>
  27 #include <linux/gfp.h>
  28
  29 #include <asm/io.h>
  30 #include <asm/prom.h>
  31 #include <asm/pci-bridge.h>
  32 #include <asm/ppc-pci.h>
  33 #include <asm/firmware.h>
  34
  35 /*
  36  * The function is used to find the firmware data of one
  37  * specific PCI device, which is attached to the indicated
  38  * PCI bus. For VFs, their firmware data is linked to that
  39  * one of PF's bridge. For other devices, their firmware
  40  * data is linked to that of their bridge.
  41  */
  42 static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus)
  43 {
  44         struct pci_bus *pbus;
  45         struct device_node *dn;
  46         struct pci_dn *pdn;
  47
  48         /*
  49          * We probably have virtual bus which doesn't
  50          * have associated bridge.
  51          */
  52         pbus = bus;
  53         while (pbus) {
  54                 if (pci_is_root_bus(pbus) || pbus->self)
  55                         break;
  56
  57                 pbus = pbus->parent;
  58         }
  59
  60         /*
  61          * Except virtual bus, all PCI buses should
  62          * have device nodes.
  63          */
  64         dn = pci_bus_to_OF_node(pbus);
  65         pdn = dn ? PCI_DN(dn) : NULL;
  66
  67         return pdn;
  68 }
  69
  70 struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus,
  71                                     int devfn)
  72 {
  73         struct device_node *dn = NULL;
  74         struct pci_dn *parent, *pdn;
  75         struct pci_dev *pdev = NULL;
  76
  77         /* Fast path: fetch from PCI device */
  78         list_for_each_entry(pdev, &bus->devices, bus_list) {
  79                 if (pdev->devfn == devfn) {
  80                         if (pdev->dev.archdata.pci_data)
  81                                 return pdev->dev.archdata.pci_data;
  82
  83                         dn = pci_device_to_OF_node(pdev);
  84                         break;
  85                 }
  86         }
  87
  88         /* Fast path: fetch from device node */
  89         pdn = dn ? PCI_DN(dn) : NULL;
  90         if (pdn)
  91                 return pdn;
  92
  93         /* Slow path: fetch from firmware data hierarchy */
  94         parent = pci_bus_to_pdn(bus);
  95         if (!parent)
  96                 return NULL;
  97
  98         list_for_each_entry(pdn, &parent->child_list, list) {
  99                 if (pdn->busno == bus->number &&
 100                     pdn->devfn == devfn)
 101                         return pdn;
 102         }
 103
 104         return NULL;
 105 }
 106
 107 struct pci_dn *pci_get_pdn(struct pci_dev *pdev)
 108 {
 109         struct device_node *dn;
 110         struct pci_dn *parent, *pdn;
 111
 112         /* Search device directly */
 113         if (pdev->dev.archdata.pci_data)
 114                 return pdev->dev.archdata.pci_data;
 115
 116         /* Check device node */
 117         dn = pci_device_to_OF_node(pdev);
 118         pdn = dn ? PCI_DN(dn) : NULL;
 119         if (pdn)
 120                 return pdn;
 121
 122         /*
 123          * VFs don't have device nodes. We hook their
 124          * firmware data to PF's bridge.
 125          */
 126         parent = pci_bus_to_pdn(pdev->bus);
 127         if (!parent)
 128                 return NULL;
 129
 130         list_for_each_entry(pdn, &parent->child_list, list) {
 131                 if (pdn->busno == pdev->bus->number &&
 132                     pdn->devfn == pdev->devfn)
 133                         return pdn;
 134         }
 135
 136         return NULL;
 137 }
 138
 139 #ifdef CONFIG_PCI_IOV
 140 static struct pci_dn *add_one_dev_pci_data(struct pci_dn *parent,
 141                                            struct pci_dev *pdev,
 142                                            int busno, int devfn)
 143 {
 144         struct pci_dn *pdn;
 145
 146         /* Except PHB, we always have the parent */
 147         if (!parent)
 148                 return NULL;
 149
 150         pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
 151         if (!pdn) {
 152                 dev_warn(&pdev->dev, "%s: Out of memory!\n", __func__);
 153                 return NULL;
 154         }
 155
 156         pdn->phb = parent->phb;
 157         pdn->parent = parent;
 158         pdn->busno = busno;
 159         pdn->devfn = devfn;
 160 #ifdef CONFIG_PPC_POWERNV
 161         pdn->pe_number = IODA_INVALID_PE;
 162 #endif
 163         INIT_LIST_HEAD(&pdn->child_list);
 164         INIT_LIST_HEAD(&pdn->list);
 165         list_add_tail(&pdn->list, &parent->child_list);
 166
 167         /*
 168          * If we already have PCI device instance, lets
 169          * bind them.
 170          */
 171         if (pdev)
 172                 pdev->dev.archdata.pci_data = pdn;
 173
 174         return pdn;
 175 }
 176 #endif
 177
 178 struct pci_dn *add_dev_pci_data(struct pci_dev *pdev)
 179 {
 180 #ifdef CONFIG_PCI_IOV
 181         struct pci_dn *parent, *pdn;
 182         int i;
 183
 184         /* Only support IOV for now */
 185         if (!pdev->is_physfn)
 186                 return pci_get_pdn(pdev);
 187
 188         /* Check if VFs have been populated */
 189         pdn = pci_get_pdn(pdev);
 190         if (!pdn || (pdn->flags & PCI_DN_FLAG_IOV_VF))
 191                 return NULL;
 192
 193         pdn->flags |= PCI_DN_FLAG_IOV_VF;
 194         parent = pci_bus_to_pdn(pdev->bus);
 195         if (!parent)
 196                 return NULL;
 197
 198         for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
 199                 pdn = add_one_dev_pci_data(parent, NULL,
 200                                            pci_iov_virtfn_bus(pdev, i),
 201                                            pci_iov_virtfn_devfn(pdev, i));
 202                 if (!pdn) {
 203                         dev_warn(&pdev->dev, "%s: Cannot create firmware data for VF#%d\n",
 204                                  __func__, i);
 205                         return NULL;
 206                 }
 207         }
 208 #endif /* CONFIG_PCI_IOV */
 209
 210         return pci_get_pdn(pdev);
 211 }
 212
 213 void remove_dev_pci_data(struct pci_dev *pdev)
 214 {
 215 #ifdef CONFIG_PCI_IOV
 216         struct pci_dn *parent;
 217         struct pci_dn *pdn, *tmp;
 218         int i;
 219
 220         /*
 221          * VF and VF PE are created/released dynamically, so we need to
 222          * bind/unbind them.  Otherwise the VF and VF PE would be mismatched
 223          * when re-enabling SR-IOV.
 224          */
 225         if (pdev->is_virtfn) {
 226                 pdn = pci_get_pdn(pdev);
 227 #ifdef CONFIG_PPC_POWERNV
 228                 pdn->pe_number = IODA_INVALID_PE;
 229 #endif
 230                 return;
 231         }
 232
 233         /* Only support IOV PF for now */
 234         if (!pdev->is_physfn)
 235                 return;
 236
 237         /* Check if VFs have been populated */
 238         pdn = pci_get_pdn(pdev);
 239         if (!pdn || !(pdn->flags & PCI_DN_FLAG_IOV_VF))
 240                 return;
 241
 242         pdn->flags &= ~PCI_DN_FLAG_IOV_VF;
 243         parent = pci_bus_to_pdn(pdev->bus);
 244         if (!parent)
 245                 return;
 246
 247         /*
 248          * We might introduce flag to pci_dn in future
 249          * so that we can release VF's firmware data in
 250          * a batch mode.
 251          */
 252         for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
 253                 list_for_each_entry_safe(pdn, tmp,
 254                         &parent->child_list, list) {
 255                         if (pdn->busno != pci_iov_virtfn_bus(pdev, i) ||
 256                             pdn->devfn != pci_iov_virtfn_devfn(pdev, i))
 257                                 continue;
 258
 259                         if (!list_empty(&pdn->list))
 260                                 list_del(&pdn->list);
 261
 262                         kfree(pdn);
 263                 }
 264         }
 265 #endif /* CONFIG_PCI_IOV */
 266 }
 267
 268 /*
 269  * Traverse_func that inits the PCI fields of the device node.
 270  * NOTE: this *must* be done before read/write config to the device.
 271  */
 272 void *update_dn_pci_info(struct device_node *dn, void *data)
 273 {
 274         struct pci_controller *phb = data;
 275         const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL);
 276         const __be32 *regs;
 277         struct device_node *parent;
 278         struct pci_dn *pdn;
 279
 280         pdn = zalloc_maybe_bootmem(sizeof(*pdn), GFP_KERNEL);
 281         if (pdn == NULL)
 282                 return NULL;
 283         dn->data = pdn;
 284         pdn->node = dn;
 285         pdn->phb = phb;
 286 #ifdef CONFIG_PPC_POWERNV
 287         pdn->pe_number = IODA_INVALID_PE;
 288 #endif
 289         regs = of_get_property(dn, "reg", NULL);
 290         if (regs) {
 291                 u32 addr = of_read_number(regs, 1);
 292
 293                 /* First register entry is addr (00BBSS00)  */
 294                 pdn->busno = (addr >> 16) & 0xff;
 295                 pdn->devfn = (addr >> 8) & 0xff;
 296         }
 297
 298         /* vendor/device IDs and class code */
 299         regs = of_get_property(dn, "vendor-id", NULL);
 300         pdn->vendor_id = regs ? of_read_number(regs, 1) : 0;
 301         regs = of_get_property(dn, "device-id", NULL);
 302         pdn->device_id = regs ? of_read_number(regs, 1) : 0;
 303         regs = of_get_property(dn, "class-code", NULL);
 304         pdn->class_code = regs ? of_read_number(regs, 1) : 0;
 305
 306         /* Extended config space */
 307         pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);
 308
 309         /* Attach to parent node */
 310         INIT_LIST_HEAD(&pdn->child_list);
 311         INIT_LIST_HEAD(&pdn->list);
 312         parent = of_get_parent(dn);
 313         pdn->parent = parent ? PCI_DN(parent) : NULL;
 314         if (pdn->parent)
 315                 list_add_tail(&pdn->list, &pdn->parent->child_list);
 316
 317         return NULL;
 318 }
 319
 320 /*
 321  * Traverse a device tree stopping each PCI device in the tree.
 322  * This is done depth first.  As each node is processed, a "pre"
 323  * function is called and the children are processed recursively.
 324  *
 325  * The "pre" func returns a value.  If non-zero is returned from
 326  * the "pre" func, the traversal stops and this value is returned.
 327  * This return value is useful when using traverse as a method of
 328  * finding a device.
 329  *
 330  * NOTE: we do not run the func for devices that do not appear to
 331  * be PCI except for the start node which we assume (this is good
 332  * because the start node is often a phb which may be missing PCI
 333  * properties).
 334  * We use the class-code as an indicator. If we run into
 335  * one of these nodes we also assume its siblings are non-pci for
 336  * performance.
 337  */
 338 void *traverse_pci_devices(struct device_node *start, traverse_func pre,
 339                 void *data)
 340 {
 341         struct device_node *dn, *nextdn;
 342         void *ret;
 343
 344         /* We started with a phb, iterate all childs */
 345         for (dn = start->child; dn; dn = nextdn) {
 346                 const __be32 *classp;
 347                 u32 class = 0;
 348
 349                 nextdn = NULL;
 350                 classp = of_get_property(dn, "class-code", NULL);
 351                 if (classp)
 352                         class = of_read_number(classp, 1);
 353
 354                 if (pre && ((ret = pre(dn, data)) != NULL))
 355                         return ret;
 356
 357                 /* If we are a PCI bridge, go down */
 358                 if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI ||
 359                                   (class >> 8) == PCI_CLASS_BRIDGE_CARDBUS))
 360                         /* Depth first...do children */
 361                         nextdn = dn->child;
 362                 else if (dn->sibling)
 363                         /* ok, try next sibling instead. */
 364                         nextdn = dn->sibling;
 365                 if (!nextdn) {
 366                         /* Walk up to next valid sibling. */
 367                         do {
 368                                 dn = dn->parent;
 369                                 if (dn == start)
 370                                         return NULL;
 371                         } while (dn->sibling == NULL);
 372                         nextdn = dn->sibling;
 373                 }
 374         }
 375         return NULL;
 376 }
 377
 378 static struct pci_dn *pci_dn_next_one(struct pci_dn *root,
 379                                       struct pci_dn *pdn)
 380 {
 381         struct list_head *next = pdn->child_list.next;
 382
 383         if (next != &pdn->child_list)
 384                 return list_entry(next, struct pci_dn, list);
 385
 386         while (1) {
 387                 if (pdn == root)
 388                         return NULL;
 389
 390                 next = pdn->list.next;
 391                 if (next != &pdn->parent->child_list)
 392                         break;
 393
 394                 pdn = pdn->parent;
 395         }
 396
 397         return list_entry(next, struct pci_dn, list);
 398 }
 399
 400 void *traverse_pci_dn(struct pci_dn *root,
 401                       void *(*fn)(struct pci_dn *, void *),
 402                       void *data)
 403 {
 404         struct pci_dn *pdn = root;
 405         void *ret;
 406
 407         /* Only scan the child nodes */
 408         for (pdn = pci_dn_next_one(root, pdn); pdn;
 409              pdn = pci_dn_next_one(root, pdn)) {
 410                 ret = fn(pdn, data);
 411                 if (ret)
 412                         return ret;
 413         }
 414
 415         return NULL;
 416 }
 417
 418 /**
 419  * pci_devs_phb_init_dynamic - setup pci devices under this PHB
 420  * phb: pci-to-host bridge (top-level bridge connecting to cpu)
 421  *
 422  * This routine is called both during boot, (before the memory
 423  * subsystem is set up, before kmalloc is valid) and during the
 424  * dynamic lpar operation of adding a PHB to a running system.
 425  */
 426 void pci_devs_phb_init_dynamic(struct pci_controller *phb)
 427 {
 428         struct device_node *dn = phb->dn;
 429         struct pci_dn *pdn;
 430
 431         /* PHB nodes themselves must not match */
 432         update_dn_pci_info(dn, phb);
 433         pdn = dn->data;
 434         if (pdn) {
 435                 pdn->devfn = pdn->busno = -1;
 436                 pdn->vendor_id = pdn->device_id = pdn->class_code = 0;
 437                 pdn->phb = phb;
 438                 phb->pci_data = pdn;
 439         }
 440
 441         /* Update dn->phb ptrs for new phb and children devices */
 442         traverse_pci_devices(dn, update_dn_pci_info, phb);
 443 }
 444
 445 /**
 446  * pci_devs_phb_init - Initialize phbs and pci devs under them.
 447  *
 448  * This routine walks over all phb's (pci-host bridges) on the
 449  * system, and sets up assorted pci-related structures
 450  * (including pci info in the device node structs) for each
 451  * pci device found underneath.  This routine runs once,
 452  * early in the boot sequence.
 453  */
 454 void __init pci_devs_phb_init(void)
 455 {
 456         struct pci_controller *phb, *tmp;
 457
 458         /* This must be done first so the device nodes have valid pci info! */
 459         list_for_each_entry_safe(phb, tmp, &hose_list, list_node)
 460                 pci_devs_phb_init_dynamic(phb);
 461 }
 462
 463 static void pci_dev_pdn_setup(struct pci_dev *pdev)
 464 {
 465         struct pci_dn *pdn;
 466
 467         if (pdev->dev.archdata.pci_data)
 468                 return;
 469
 470         /* Setup the fast path */
 471         pdn = pci_get_pdn(pdev);
 472         pdev->dev.archdata.pci_data = pdn;
 473 }
 474 DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, pci_dev_pdn_setup);