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 static struct bus_type vio_bus_type;
  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 static struct iommu_table *vio_build_iommu_table(struct vio_dev *dev)
  50 {
  51         const unsigned char *dma_window;
  52         struct iommu_table *tbl;
  53         unsigned long offset, size;
  54
  55         if (firmware_has_feature(FW_FEATURE_ISERIES))
  56                 return vio_build_iommu_table_iseries(dev);
  57
  58         dma_window = of_get_property(dev->dev.archdata.of_node,
  59                                   "ibm,my-dma-window", NULL);
  60         if (!dma_window)
  61                 return NULL;
  62
  63         tbl = kmalloc(sizeof(*tbl), GFP_KERNEL);
  64
  65         of_parse_dma_window(dev->dev.archdata.of_node, dma_window,
  66                             &tbl->it_index, &offset, &size);
  67
  68         /* TCE table size - measured in tce entries */
  69         tbl->it_size = size >> IOMMU_PAGE_SHIFT;
  70         /* offset for VIO should always be 0 */
  71         tbl->it_offset = offset >> IOMMU_PAGE_SHIFT;
  72         tbl->it_busno = 0;
  73         tbl->it_type = TCE_VB;
  74
  75         return iommu_init_table(tbl, -1);
  76 }
  77
  78 /**
  79  * vio_match_device: - Tell if a VIO device has a matching
  80  *                      VIO device id structure.
  81  * @ids:        array of VIO device id structures to search in
  82  * @dev:        the VIO device structure to match against
  83  *
  84  * Used by a driver to check whether a VIO device present in the
  85  * system is in its list of supported devices. Returns the matching
  86  * vio_device_id structure or NULL if there is no match.
  87  */
  88 static const struct vio_device_id *vio_match_device(
  89                 const struct vio_device_id *ids, const struct vio_dev *dev)
  90 {
  91         while (ids->type[0] != '\0') {
  92                 if ((strncmp(dev->type, ids->type, strlen(ids->type)) == 0) &&
  93                     of_device_is_compatible(dev->dev.archdata.of_node,
  94                                          ids->compat))
  95                         return ids;
  96                 ids++;
  97         }
  98         return NULL;
  99 }
 100
 101 /*
 102  * Convert from struct device to struct vio_dev and pass to driver.
 103  * dev->driver has already been set by generic code because vio_bus_match
 104  * succeeded.
 105  */
 106 static int vio_bus_probe(struct device *dev)
 107 {
 108         struct vio_dev *viodev = to_vio_dev(dev);
 109         struct vio_driver *viodrv = to_vio_driver(dev->driver);
 110         const struct vio_device_id *id;
 111         int error = -ENODEV;
 112
 113         if (!viodrv->probe)
 114                 return error;
 115
 116         id = vio_match_device(viodrv->id_table, viodev);
 117         if (id)
 118                 error = viodrv->probe(viodev, id);
 119
 120         return error;
 121 }
 122
 123 /* convert from struct device to struct vio_dev and pass to driver. */
 124 static int vio_bus_remove(struct device *dev)
 125 {
 126         struct vio_dev *viodev = to_vio_dev(dev);
 127         struct vio_driver *viodrv = to_vio_driver(dev->driver);
 128
 129         if (viodrv->remove)
 130                 return viodrv->remove(viodev);
 131
 132         /* driver can't remove */
 133         return 1;
 134 }
 135
 136 /**
 137  * vio_register_driver: - Register a new vio driver
 138  * @drv:        The vio_driver structure to be registered.
 139  */
 140 int vio_register_driver(struct vio_driver *viodrv)
 141 {
 142         printk(KERN_DEBUG "%s: driver %s registering\n", __FUNCTION__,
 143                 viodrv->driver.name);
 144
 145         /* fill in 'struct driver' fields */
 146         viodrv->driver.bus = &vio_bus_type;
 147
 148         return driver_register(&viodrv->driver);
 149 }
 150 EXPORT_SYMBOL(vio_register_driver);
 151
 152 /**
 153  * vio_unregister_driver - Remove registration of vio driver.
 154  * @driver:     The vio_driver struct to be removed form registration
 155  */
 156 void vio_unregister_driver(struct vio_driver *viodrv)
 157 {
 158         driver_unregister(&viodrv->driver);
 159 }
 160 EXPORT_SYMBOL(vio_unregister_driver);
 161
 162 /* vio_dev refcount hit 0 */
 163 static void __devinit vio_dev_release(struct device *dev)
 164 {
 165         /* XXX should free TCE table */
 166         of_node_put(dev->archdata.of_node);
 167         kfree(to_vio_dev(dev));
 168 }
 169
 170 /**
 171  * vio_register_device_node: - Register a new vio device.
 172  * @of_node:    The OF node for this device.
 173  *
 174  * Creates and initializes a vio_dev structure from the data in
 175  * of_node and adds it to the list of virtual devices.
 176  * Returns a pointer to the created vio_dev or NULL if node has
 177  * NULL device_type or compatible fields.
 178  */
 179 struct vio_dev *vio_register_device_node(struct device_node *of_node)
 180 {
 181         struct vio_dev *viodev;
 182         const unsigned int *unit_address;
 183
 184         /* we need the 'device_type' property, in order to match with drivers */
 185         if (of_node->type == NULL) {
 186                 printk(KERN_WARNING "%s: node %s missing 'device_type'\n",
 187                                 __FUNCTION__,
 188                                 of_node->name ? of_node->name : "<unknown>");
 189                 return NULL;
 190         }
 191
 192         unit_address = of_get_property(of_node, "reg", NULL);
 193         if (unit_address == NULL) {
 194                 printk(KERN_WARNING "%s: node %s missing 'reg'\n",
 195                                 __FUNCTION__,
 196                                 of_node->name ? of_node->name : "<unknown>");
 197                 return NULL;
 198         }
 199
 200         /* allocate a vio_dev for this node */
 201         viodev = kzalloc(sizeof(struct vio_dev), GFP_KERNEL);
 202         if (viodev == NULL)
 203                 return NULL;
 204
 205         viodev->irq = irq_of_parse_and_map(of_node, 0);
 206
 207         snprintf(viodev->dev.bus_id, BUS_ID_SIZE, "%x", *unit_address);
 208         viodev->name = of_node->name;
 209         viodev->type = of_node->type;
 210         viodev->unit_address = *unit_address;
 211         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
 212                 unit_address = of_get_property(of_node,
 213                                 "linux,unit_address", NULL);
 214                 if (unit_address != NULL)
 215                         viodev->unit_address = *unit_address;
 216         }
 217         viodev->dev.archdata.of_node = of_node_get(of_node);
 218         viodev->dev.archdata.dma_ops = &dma_iommu_ops;
 219         viodev->dev.archdata.dma_data = vio_build_iommu_table(viodev);
 220         viodev->dev.archdata.numa_node = of_node_to_nid(of_node);
 221
 222         /* init generic 'struct device' fields: */
 223         viodev->dev.parent = &vio_bus_device.dev;
 224         viodev->dev.bus = &vio_bus_type;
 225         viodev->dev.release = vio_dev_release;
 226
 227         /* register with generic device framework */
 228         if (device_register(&viodev->dev)) {
 229                 printk(KERN_ERR "%s: failed to register device %s\n",
 230                                 __FUNCTION__, viodev->dev.bus_id);
 231                 /* XXX free TCE table */
 232                 kfree(viodev);
 233                 return NULL;
 234         }
 235
 236         return viodev;
 237 }
 238 EXPORT_SYMBOL(vio_register_device_node);
 239
 240 /**
 241  * vio_bus_init: - Initialize the virtual IO bus
 242  */
 243 static int __init vio_bus_init(void)
 244 {
 245         int err;
 246         struct device_node *node_vroot;
 247
 248         err = bus_register(&vio_bus_type);
 249         if (err) {
 250                 printk(KERN_ERR "failed to register VIO bus\n");
 251                 return err;
 252         }
 253
 254         /*
 255          * The fake parent of all vio devices, just to give us
 256          * a nice directory
 257          */
 258         err = device_register(&vio_bus_device.dev);
 259         if (err) {
 260                 printk(KERN_WARNING "%s: device_register returned %i\n",
 261                                 __FUNCTION__, err);
 262                 return err;
 263         }
 264
 265         node_vroot = of_find_node_by_name(NULL, "vdevice");
 266         if (node_vroot) {
 267                 struct device_node *of_node;
 268
 269                 /*
 270                  * Create struct vio_devices for each virtual device in
 271                  * the device tree. Drivers will associate with them later.
 272                  */
 273                 for (of_node = node_vroot->child; of_node != NULL;
 274                                 of_node = of_node->sibling)
 275                         vio_register_device_node(of_node);
 276                 of_node_put(node_vroot);
 277         }
 278
 279         return 0;
 280 }
 281 __initcall(vio_bus_init);
 282
 283 static ssize_t name_show(struct device *dev,
 284                 struct device_attribute *attr, char *buf)
 285 {
 286         return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
 287 }
 288
 289 static ssize_t devspec_show(struct device *dev,
 290                 struct device_attribute *attr, char *buf)
 291 {
 292         struct device_node *of_node = dev->archdata.of_node;
 293
 294         return sprintf(buf, "%s\n", of_node ? of_node->full_name : "none");
 295 }
 296
 297 static struct device_attribute vio_dev_attrs[] = {
 298         __ATTR_RO(name),
 299         __ATTR_RO(devspec),
 300         __ATTR_NULL
 301 };
 302
 303 void __devinit vio_unregister_device(struct vio_dev *viodev)
 304 {
 305         device_unregister(&viodev->dev);
 306 }
 307 EXPORT_SYMBOL(vio_unregister_device);
 308
 309 static int vio_bus_match(struct device *dev, struct device_driver *drv)
 310 {
 311         const struct vio_dev *vio_dev = to_vio_dev(dev);
 312         struct vio_driver *vio_drv = to_vio_driver(drv);
 313         const struct vio_device_id *ids = vio_drv->id_table;
 314
 315         return (ids != NULL) && (vio_match_device(ids, vio_dev) != NULL);
 316 }
 317
 318 static int vio_hotplug(struct device *dev, struct kobj_uevent_env *env)
 319 {
 320         const struct vio_dev *vio_dev = to_vio_dev(dev);
 321         struct device_node *dn;
 322         const char *cp;
 323
 324         dn = dev->archdata.of_node;
 325         if (!dn)
 326                 return -ENODEV;
 327         cp = of_get_property(dn, "compatible", NULL);
 328         if (!cp)
 329                 return -ENODEV;
 330
 331         add_uevent_var(env, "MODALIAS=vio:T%sS%s", vio_dev->type, cp);
 332         return 0;
 333 }
 334
 335 static struct bus_type vio_bus_type = {
 336         .name = "vio",
 337         .dev_attrs = vio_dev_attrs,
 338         .uevent = vio_hotplug,
 339         .match = vio_bus_match,
 340         .probe = vio_bus_probe,
 341         .remove = vio_bus_remove,
 342 };
 343
 344 /**
 345  * vio_get_attribute: - get attribute for virtual device
 346  * @vdev:       The vio device to get property.
 347  * @which:      The property/attribute to be extracted.
 348  * @length:     Pointer to length of returned data size (unused if NULL).
 349  *
 350  * Calls prom.c's of_get_property() to return the value of the
 351  * attribute specified by @which
 352 */
 353 const void *vio_get_attribute(struct vio_dev *vdev, char *which, int *length)
 354 {
 355         return of_get_property(vdev->dev.archdata.of_node, which, length);
 356 }
 357 EXPORT_SYMBOL(vio_get_attribute);
 358
 359 #ifdef CONFIG_PPC_PSERIES
 360 /* vio_find_name() - internal because only vio.c knows how we formatted the
 361  * kobject name
 362  */
 363 static struct vio_dev *vio_find_name(const char *name)
 364 {
 365         struct device *found;
 366
 367         found = bus_find_device_by_name(&vio_bus_type, NULL, name);
 368         if (!found)
 369                 return NULL;
 370
 371         return to_vio_dev(found);
 372 }
 373
 374 /**
 375  * vio_find_node - find an already-registered vio_dev
 376  * @vnode: device_node of the virtual device we're looking for
 377  */
 378 struct vio_dev *vio_find_node(struct device_node *vnode)
 379 {
 380         const uint32_t *unit_address;
 381         char kobj_name[BUS_ID_SIZE];
 382
 383         /* construct the kobject name from the device node */
 384         unit_address = of_get_property(vnode, "reg", NULL);
 385         if (!unit_address)
 386                 return NULL;
 387         snprintf(kobj_name, BUS_ID_SIZE, "%x", *unit_address);
 388
 389         return vio_find_name(kobj_name);
 390 }
 391 EXPORT_SYMBOL(vio_find_node);
 392
 393 int vio_enable_interrupts(struct vio_dev *dev)
 394 {
 395         int rc = h_vio_signal(dev->unit_address, VIO_IRQ_ENABLE);
 396         if (rc != H_SUCCESS)
 397                 printk(KERN_ERR "vio: Error 0x%x enabling interrupts\n", rc);
 398         return rc;
 399 }
 400 EXPORT_SYMBOL(vio_enable_interrupts);
 401
 402 int vio_disable_interrupts(struct vio_dev *dev)
 403 {
 404         int rc = h_vio_signal(dev->unit_address, VIO_IRQ_DISABLE);
 405         if (rc != H_SUCCESS)
 406                 printk(KERN_ERR "vio: Error 0x%x disabling interrupts\n", rc);
 407         return rc;
 408 }
 409 EXPORT_SYMBOL(vio_disable_interrupts);
 410 #endif /* CONFIG_PPC_PSERIES */