arch/powerpc/kernel/vio.c

   1 /*
   2  * IBM PowerPC Virtual I/O Infrastructure Support.
   3  *
   4  *    Copyright (c) 2003-2005 IBM Corp.
   5  *     Dave Engebretsen engebret@us.ibm.com
   6  *     Santiago Leon santil@us.ibm.com
   7  *     Hollis Blanchard <hollisb@us.ibm.com>
   8  *     Stephen Rothwell
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      as published by the Free Software Foundation; either version
  13  *      2 of the License, or (at your option) any later version.
  14  */
  15
  16 #include <linux/types.h>
  17 #include <linux/device.h>
  18 #include <linux/init.h>
  19 #include <linux/console.h>
  20 #include <linux/module.h>
  21 #include <linux/mm.h>
  22 #include <linux/dma-mapping.h>
  23 #include <linux/kobject.h>
  24
  25 #include <asm/iommu.h>
  26 #include <asm/dma.h>
  27 #include <asm/vio.h>
  28 #include <asm/prom.h>
  29 #include <asm/firmware.h>
  30 #include <asm/tce.h>
  31 #include <asm/abs_addr.h>
  32 #include <asm/page.h>
  33 #include <asm/hvcall.h>
  34 #include <asm/iseries/vio.h>
  35 #include <asm/iseries/hv_types.h>
  36 #include <asm/iseries/hv_lp_config.h>
  37 #include <asm/iseries/hv_call_xm.h>
  38 #include <asm/iseries/iommu.h>
  39
  40 extern struct subsystem devices_subsys; /* needed for vio_find_name() */
  41
  42 static struct vio_dev vio_bus_device  = { /* fake "parent" device */
  43         .name = vio_bus_device.dev.bus_id,
  44         .type = "",
  45         .dev.bus_id = "vio",
  46         .dev.bus = &vio_bus_type,
  47 };
  48
  49 #ifdef CONFIG_PPC_ISERIES
  50 struct device *iSeries_vio_dev = &vio_bus_device.dev;
  51 EXPORT_SYMBOL(iSeries_vio_dev);
  52
  53 static struct iommu_table veth_iommu_table;
  54 static struct iommu_table vio_iommu_table;
  55
  56 static void __init iommu_vio_init(void)
  57 {
  58         iommu_table_getparms_iSeries(255, 0, 0xff, &veth_iommu_table);
  59         veth_iommu_table.it_size /= 2;
  60         vio_iommu_table = veth_iommu_table;
  61         vio_iommu_table.it_offset += veth_iommu_table.it_size;
  62
  63         if (!iommu_init_table(&veth_iommu_table, -1))
  64                 printk("Virtual Bus VETH TCE table failed.\n");
  65         if (!iommu_init_table(&vio_iommu_table, -1))
  66                 printk("Virtual Bus VIO TCE table failed.\n");
  67 }
  68 #endif
  69
  70 static struct iommu_table *vio_build_iommu_table(struct vio_dev *dev)
  71 {
  72 #ifdef CONFIG_PPC_ISERIES
  73         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
  74                 if (strcmp(dev->type, "network") == 0)
  75                         return &veth_iommu_table;
  76                 return &vio_iommu_table;
  77         } else
  78 #endif
  79         {
  80                 const unsigned char *dma_window;
  81                 struct iommu_table *tbl;
  82                 unsigned long offset, size;
  83
  84                 dma_window = get_property(dev->dev.platform_data,
  85                                 "ibm,my-dma-window", NULL);
  86                 if (!dma_window)
  87                         return NULL;
  88
  89                 tbl = kmalloc(sizeof(*tbl), GFP_KERNEL);
  90
  91                 of_parse_dma_window(dev->dev.platform_data, dma_window,
  92                                 &tbl->it_index, &offset, &size);
  93
  94                 /* TCE table size - measured in tce entries */
  95                 tbl->it_size = size >> PAGE_SHIFT;
  96                 /* offset for VIO should always be 0 */
  97                 tbl->it_offset = offset >> PAGE_SHIFT;
  98                 tbl->it_busno = 0;
  99                 tbl->it_type = TCE_VB;
 100
 101                 return iommu_init_table(tbl, -1);
 102         }
 103 }
 104
 105 /**
 106  * vio_match_device: - Tell if a VIO device has a matching
 107  *                      VIO device id structure.
 108  * @ids:        array of VIO device id structures to search in
 109  * @dev:        the VIO device structure to match against
 110  *
 111  * Used by a driver to check whether a VIO device present in the
 112  * system is in its list of supported devices. Returns the matching
 113  * vio_device_id structure or NULL if there is no match.
 114  */
 115 static const struct vio_device_id *vio_match_device(
 116                 const struct vio_device_id *ids, const struct vio_dev *dev)
 117 {
 118         while (ids->type[0] != '\0') {
 119                 if ((strncmp(dev->type, ids->type, strlen(ids->type)) == 0) &&
 120                     device_is_compatible(dev->dev.platform_data, ids->compat))
 121                         return ids;
 122                 ids++;
 123         }
 124         return NULL;
 125 }
 126
 127 /*
 128  * Convert from struct device to struct vio_dev and pass to driver.
 129  * dev->driver has already been set by generic code because vio_bus_match
 130  * succeeded.
 131  */
 132 static int vio_bus_probe(struct device *dev)
 133 {
 134         struct vio_dev *viodev = to_vio_dev(dev);
 135         struct vio_driver *viodrv = to_vio_driver(dev->driver);
 136         const struct vio_device_id *id;
 137         int error = -ENODEV;
 138
 139         if (!viodrv->probe)
 140                 return error;
 141
 142         id = vio_match_device(viodrv->id_table, viodev);
 143         if (id)
 144                 error = viodrv->probe(viodev, id);
 145
 146         return error;
 147 }
 148
 149 /* convert from struct device to struct vio_dev and pass to driver. */
 150 static int vio_bus_remove(struct device *dev)
 151 {
 152         struct vio_dev *viodev = to_vio_dev(dev);
 153         struct vio_driver *viodrv = to_vio_driver(dev->driver);
 154
 155         if (viodrv->remove)
 156                 return viodrv->remove(viodev);
 157
 158         /* driver can't remove */
 159         return 1;
 160 }
 161
 162 /* convert from struct device to struct vio_dev and pass to driver. */
 163 static void vio_bus_shutdown(struct device *dev)
 164 {
 165         struct vio_dev *viodev = to_vio_dev(dev);
 166         struct vio_driver *viodrv = to_vio_driver(dev->driver);
 167
 168         if (dev->driver && viodrv->shutdown)
 169                 viodrv->shutdown(viodev);
 170 }
 171
 172 /**
 173  * vio_register_driver: - Register a new vio driver
 174  * @drv:        The vio_driver structure to be registered.
 175  */
 176 int vio_register_driver(struct vio_driver *viodrv)
 177 {
 178         printk(KERN_DEBUG "%s: driver %s registering\n", __FUNCTION__,
 179                 viodrv->driver.name);
 180
 181         /* fill in 'struct driver' fields */
 182         viodrv->driver.bus = &vio_bus_type;
 183
 184         return driver_register(&viodrv->driver);
 185 }
 186 EXPORT_SYMBOL(vio_register_driver);
 187
 188 /**
 189  * vio_unregister_driver - Remove registration of vio driver.
 190  * @driver:     The vio_driver struct to be removed form registration
 191  */
 192 void vio_unregister_driver(struct vio_driver *viodrv)
 193 {
 194         driver_unregister(&viodrv->driver);
 195 }
 196 EXPORT_SYMBOL(vio_unregister_driver);
 197
 198 /* vio_dev refcount hit 0 */
 199 static void __devinit vio_dev_release(struct device *dev)
 200 {
 201         if (dev->platform_data) {
 202                 /* XXX free TCE table */
 203                 of_node_put(dev->platform_data);
 204         }
 205         kfree(to_vio_dev(dev));
 206 }
 207
 208 /**
 209  * vio_register_device_node: - Register a new vio device.
 210  * @of_node:    The OF node for this device.
 211  *
 212  * Creates and initializes a vio_dev structure from the data in
 213  * of_node (dev.platform_data) and adds it to the list of virtual devices.
 214  * Returns a pointer to the created vio_dev or NULL if node has
 215  * NULL device_type or compatible fields.
 216  */
 217 struct vio_dev * __devinit vio_register_device_node(struct device_node *of_node)
 218 {
 219         struct vio_dev *viodev;
 220         const unsigned int *unit_address;
 221
 222         /* we need the 'device_type' property, in order to match with drivers */
 223         if (of_node->type == NULL) {
 224                 printk(KERN_WARNING "%s: node %s missing 'device_type'\n",
 225                                 __FUNCTION__,
 226                                 of_node->name ? of_node->name : "<unknown>");
 227                 return NULL;
 228         }
 229
 230         unit_address = get_property(of_node, "reg", NULL);
 231         if (unit_address == NULL) {
 232                 printk(KERN_WARNING "%s: node %s missing 'reg'\n",
 233                                 __FUNCTION__,
 234                                 of_node->name ? of_node->name : "<unknown>");
 235                 return NULL;
 236         }
 237
 238         /* allocate a vio_dev for this node */
 239         viodev = kzalloc(sizeof(struct vio_dev), GFP_KERNEL);
 240         if (viodev == NULL)
 241                 return NULL;
 242
 243         viodev->dev.platform_data = of_node_get(of_node);
 244
 245         viodev->irq = irq_of_parse_and_map(of_node, 0);
 246
 247         snprintf(viodev->dev.bus_id, BUS_ID_SIZE, "%x", *unit_address);
 248         viodev->name = of_node->name;
 249         viodev->type = of_node->type;
 250         viodev->unit_address = *unit_address;
 251         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
 252                 unit_address = get_property(of_node,
 253                                 "linux,unit_address", NULL);
 254                 if (unit_address != NULL)
 255                         viodev->unit_address = *unit_address;
 256         }
 257         viodev->iommu_table = vio_build_iommu_table(viodev);
 258
 259         /* init generic 'struct device' fields: */
 260         viodev->dev.parent = &vio_bus_device.dev;
 261         viodev->dev.bus = &vio_bus_type;
 262         viodev->dev.release = vio_dev_release;
 263
 264         /* register with generic device framework */
 265         if (device_register(&viodev->dev)) {
 266                 printk(KERN_ERR "%s: failed to register device %s\n",
 267                                 __FUNCTION__, viodev->dev.bus_id);
 268                 /* XXX free TCE table */
 269                 kfree(viodev);
 270                 return NULL;
 271         }
 272
 273         return viodev;
 274 }
 275 EXPORT_SYMBOL(vio_register_device_node);
 276
 277 /**
 278  * vio_bus_init: - Initialize the virtual IO bus
 279  */
 280 static int __init vio_bus_init(void)
 281 {
 282         int err;
 283         struct device_node *node_vroot;
 284
 285 #ifdef CONFIG_PPC_ISERIES
 286         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
 287                 iommu_vio_init();
 288                 vio_bus_device.iommu_table = &vio_iommu_table;
 289                 iSeries_vio_dev = &vio_bus_device.dev;
 290         }
 291 #endif
 292
 293         err = bus_register(&vio_bus_type);
 294         if (err) {
 295                 printk(KERN_ERR "failed to register VIO bus\n");
 296                 return err;
 297         }
 298
 299         /*
 300          * The fake parent of all vio devices, just to give us
 301          * a nice directory
 302          */
 303         err = device_register(&vio_bus_device.dev);
 304         if (err) {
 305                 printk(KERN_WARNING "%s: device_register returned %i\n",
 306                                 __FUNCTION__, err);
 307                 return err;
 308         }
 309
 310         node_vroot = find_devices("vdevice");
 311         if (node_vroot) {
 312                 struct device_node *of_node;
 313
 314                 /*
 315                  * Create struct vio_devices for each virtual device in
 316                  * the device tree. Drivers will associate with them later.
 317                  */
 318                 for (of_node = node_vroot->child; of_node != NULL;
 319                                 of_node = of_node->sibling) {
 320                         printk(KERN_DEBUG "%s: processing %p\n",
 321                                         __FUNCTION__, of_node);
 322                         vio_register_device_node(of_node);
 323                 }
 324         }
 325
 326         return 0;
 327 }
 328 __initcall(vio_bus_init);
 329
 330 static ssize_t name_show(struct device *dev,
 331                 struct device_attribute *attr, char *buf)
 332 {
 333         return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
 334 }
 335
 336 static ssize_t devspec_show(struct device *dev,
 337                 struct device_attribute *attr, char *buf)
 338 {
 339         struct device_node *of_node = dev->platform_data;
 340
 341         return sprintf(buf, "%s\n", of_node ? of_node->full_name : "none");
 342 }
 343
 344 static struct device_attribute vio_dev_attrs[] = {
 345         __ATTR_RO(name),
 346         __ATTR_RO(devspec),
 347         __ATTR_NULL
 348 };
 349
 350 void __devinit vio_unregister_device(struct vio_dev *viodev)
 351 {
 352         device_unregister(&viodev->dev);
 353 }
 354 EXPORT_SYMBOL(vio_unregister_device);
 355
 356 static dma_addr_t vio_map_single(struct device *dev, void *vaddr,
 357                           size_t size, enum dma_data_direction direction)
 358 {
 359         return iommu_map_single(to_vio_dev(dev)->iommu_table, vaddr, size,
 360                         ~0ul, direction);
 361 }
 362
 363 static void vio_unmap_single(struct device *dev, dma_addr_t dma_handle,
 364                       size_t size, enum dma_data_direction direction)
 365 {
 366         iommu_unmap_single(to_vio_dev(dev)->iommu_table, dma_handle, size,
 367                         direction);
 368 }
 369
 370 static int vio_map_sg(struct device *dev, struct scatterlist *sglist,
 371                 int nelems, enum dma_data_direction direction)
 372 {
 373         return iommu_map_sg(dev, to_vio_dev(dev)->iommu_table, sglist,
 374                         nelems, ~0ul, direction);
 375 }
 376
 377 static void vio_unmap_sg(struct device *dev, struct scatterlist *sglist,
 378                 int nelems, enum dma_data_direction direction)
 379 {
 380         iommu_unmap_sg(to_vio_dev(dev)->iommu_table, sglist, nelems, direction);
 381 }
 382
 383 static void *vio_alloc_coherent(struct device *dev, size_t size,
 384                            dma_addr_t *dma_handle, gfp_t flag)
 385 {
 386         return iommu_alloc_coherent(to_vio_dev(dev)->iommu_table, size,
 387                         dma_handle, ~0ul, flag, -1);
 388 }
 389
 390 static void vio_free_coherent(struct device *dev, size_t size,
 391                          void *vaddr, dma_addr_t dma_handle)
 392 {
 393         iommu_free_coherent(to_vio_dev(dev)->iommu_table, size, vaddr,
 394                         dma_handle);
 395 }
 396
 397 static int vio_dma_supported(struct device *dev, u64 mask)
 398 {
 399         return 1;
 400 }
 401
 402 struct dma_mapping_ops vio_dma_ops = {
 403         .alloc_coherent = vio_alloc_coherent,
 404         .free_coherent = vio_free_coherent,
 405         .map_single = vio_map_single,
 406         .unmap_single = vio_unmap_single,
 407         .map_sg = vio_map_sg,
 408         .unmap_sg = vio_unmap_sg,
 409         .dma_supported = vio_dma_supported,
 410 };
 411
 412 static int vio_bus_match(struct device *dev, struct device_driver *drv)
 413 {
 414         const struct vio_dev *vio_dev = to_vio_dev(dev);
 415         struct vio_driver *vio_drv = to_vio_driver(drv);
 416         const struct vio_device_id *ids = vio_drv->id_table;
 417
 418         return (ids != NULL) && (vio_match_device(ids, vio_dev) != NULL);
 419 }
 420
 421 static int vio_hotplug(struct device *dev, char **envp, int num_envp,
 422                         char *buffer, int buffer_size)
 423 {
 424         const struct vio_dev *vio_dev = to_vio_dev(dev);
 425         struct device_node *dn = dev->platform_data;
 426         const char *cp;
 427         int length;
 428
 429         if (!num_envp)
 430                 return -ENOMEM;
 431
 432         if (!dn)
 433                 return -ENODEV;
 434         cp = get_property(dn, "compatible", &length);
 435         if (!cp)
 436                 return -ENODEV;
 437
 438         envp[0] = buffer;
 439         length = scnprintf(buffer, buffer_size, "MODALIAS=vio:T%sS%s",
 440                                 vio_dev->type, cp);
 441         if ((buffer_size - length) <= 0)
 442                 return -ENOMEM;
 443         envp[1] = NULL;
 444         return 0;
 445 }
 446
 447 struct bus_type vio_bus_type = {
 448         .name = "vio",
 449         .dev_attrs = vio_dev_attrs,
 450         .uevent = vio_hotplug,
 451         .match = vio_bus_match,
 452         .probe = vio_bus_probe,
 453         .remove = vio_bus_remove,
 454         .shutdown = vio_bus_shutdown,
 455 };
 456
 457 /**
 458  * vio_get_attribute: - get attribute for virtual device
 459  * @vdev:       The vio device to get property.
 460  * @which:      The property/attribute to be extracted.
 461  * @length:     Pointer to length of returned data size (unused if NULL).
 462  *
 463  * Calls prom.c's get_property() to return the value of the
 464  * attribute specified by @which
 465 */
 466 const void *vio_get_attribute(struct vio_dev *vdev, char *which, int *length)
 467 {
 468         return get_property(vdev->dev.platform_data, which, length);
 469 }
 470 EXPORT_SYMBOL(vio_get_attribute);
 471
 472 #ifdef CONFIG_PPC_PSERIES
 473 /* vio_find_name() - internal because only vio.c knows how we formatted the
 474  * kobject name
 475  * XXX once vio_bus_type.devices is actually used as a kset in
 476  * drivers/base/bus.c, this function should be removed in favor of
 477  * "device_find(kobj_name, &vio_bus_type)"
 478  */
 479 static struct vio_dev *vio_find_name(const char *kobj_name)
 480 {
 481         struct kobject *found;
 482
 483         found = kset_find_obj(&devices_subsys.kset, kobj_name);
 484         if (!found)
 485                 return NULL;
 486
 487         return to_vio_dev(container_of(found, struct device, kobj));
 488 }
 489
 490 /**
 491  * vio_find_node - find an already-registered vio_dev
 492  * @vnode: device_node of the virtual device we're looking for
 493  */
 494 struct vio_dev *vio_find_node(struct device_node *vnode)
 495 {
 496         const uint32_t *unit_address;
 497         char kobj_name[BUS_ID_SIZE];
 498
 499         /* construct the kobject name from the device node */
 500         unit_address = get_property(vnode, "reg", NULL);
 501         if (!unit_address)
 502                 return NULL;
 503         snprintf(kobj_name, BUS_ID_SIZE, "%x", *unit_address);
 504
 505         return vio_find_name(kobj_name);
 506 }
 507 EXPORT_SYMBOL(vio_find_node);
 508
 509 int vio_enable_interrupts(struct vio_dev *dev)
 510 {
 511         int rc = h_vio_signal(dev->unit_address, VIO_IRQ_ENABLE);
 512         if (rc != H_SUCCESS)
 513                 printk(KERN_ERR "vio: Error 0x%x enabling interrupts\n", rc);
 514         return rc;
 515 }
 516 EXPORT_SYMBOL(vio_enable_interrupts);
 517
 518 int vio_disable_interrupts(struct vio_dev *dev)
 519 {
 520         int rc = h_vio_signal(dev->unit_address, VIO_IRQ_DISABLE);
 521         if (rc != H_SUCCESS)
 522                 printk(KERN_ERR "vio: Error 0x%x disabling interrupts\n", rc);
 523         return rc;
 524 }
 525 EXPORT_SYMBOL(vio_disable_interrupts);
 526 #endif /* CONFIG_PPC_PSERIES */