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 kset devices_subsys; /* needed for vio_find_name() */
  41
  42 static struct bus_type vio_bus_type;
  43
  44 static struct vio_dev vio_bus_device  = { /* fake "parent" device */
  45         .name = vio_bus_device.dev.bus_id,
  46         .type = "",
  47         .dev.bus_id = "vio",
  48         .dev.bus = &vio_bus_type,
  49 };
  50
  51 static struct iommu_table *vio_build_iommu_table(struct vio_dev *dev)
  52 {
  53         const unsigned char *dma_window;
  54         struct iommu_table *tbl;
  55         unsigned long offset, size;
  56
  57         if (firmware_has_feature(FW_FEATURE_ISERIES))
  58                 return vio_build_iommu_table_iseries(dev);
  59
  60         dma_window = of_get_property(dev->dev.archdata.of_node,
  61                                   "ibm,my-dma-window", NULL);
  62         if (!dma_window)
  63                 return NULL;
  64
  65         tbl = kmalloc(sizeof(*tbl), GFP_KERNEL);
  66
  67         of_parse_dma_window(dev->dev.archdata.of_node, dma_window,
  68                             &tbl->it_index, &offset, &size);
  69
  70         /* TCE table size - measured in tce entries */
  71         tbl->it_size = size >> IOMMU_PAGE_SHIFT;
  72         /* offset for VIO should always be 0 */
  73         tbl->it_offset = offset >> IOMMU_PAGE_SHIFT;
  74         tbl->it_busno = 0;
  75         tbl->it_type = TCE_VB;
  76
  77         return iommu_init_table(tbl, -1);
  78 }
  79
  80 /**
  81  * vio_match_device: - Tell if a VIO device has a matching
  82  *                      VIO device id structure.
  83  * @ids:        array of VIO device id structures to search in
  84  * @dev:        the VIO device structure to match against
  85  *
  86  * Used by a driver to check whether a VIO device present in the
  87  * system is in its list of supported devices. Returns the matching
  88  * vio_device_id structure or NULL if there is no match.
  89  */
  90 static const struct vio_device_id *vio_match_device(
  91                 const struct vio_device_id *ids, const struct vio_dev *dev)
  92 {
  93         while (ids->type[0] != '\0') {
  94                 if ((strncmp(dev->type, ids->type, strlen(ids->type)) == 0) &&
  95                     of_device_is_compatible(dev->dev.archdata.of_node,
  96                                          ids->compat))
  97                         return ids;
  98                 ids++;
  99         }
 100         return NULL;
 101 }
 102
 103 /*
 104  * Convert from struct device to struct vio_dev and pass to driver.
 105  * dev->driver has already been set by generic code because vio_bus_match
 106  * succeeded.
 107  */
 108 static int vio_bus_probe(struct device *dev)
 109 {
 110         struct vio_dev *viodev = to_vio_dev(dev);
 111         struct vio_driver *viodrv = to_vio_driver(dev->driver);
 112         const struct vio_device_id *id;
 113         int error = -ENODEV;
 114
 115         if (!viodrv->probe)
 116                 return error;
 117
 118         id = vio_match_device(viodrv->id_table, viodev);
 119         if (id)
 120                 error = viodrv->probe(viodev, id);
 121
 122         return error;
 123 }
 124
 125 /* convert from struct device to struct vio_dev and pass to driver. */
 126 static int vio_bus_remove(struct device *dev)
 127 {
 128         struct vio_dev *viodev = to_vio_dev(dev);
 129         struct vio_driver *viodrv = to_vio_driver(dev->driver);
 130
 131         if (viodrv->remove)
 132                 return viodrv->remove(viodev);
 133
 134         /* driver can't remove */
 135         return 1;
 136 }
 137
 138 /**
 139  * vio_register_driver: - Register a new vio driver
 140  * @drv:        The vio_driver structure to be registered.
 141  */
 142 int vio_register_driver(struct vio_driver *viodrv)
 143 {
 144         printk(KERN_DEBUG "%s: driver %s registering\n", __FUNCTION__,
 145                 viodrv->driver.name);
 146
 147         /* fill in 'struct driver' fields */
 148         viodrv->driver.bus = &vio_bus_type;
 149
 150         return driver_register(&viodrv->driver);
 151 }
 152 EXPORT_SYMBOL(vio_register_driver);
 153
 154 /**
 155  * vio_unregister_driver - Remove registration of vio driver.
 156  * @driver:     The vio_driver struct to be removed form registration
 157  */
 158 void vio_unregister_driver(struct vio_driver *viodrv)
 159 {
 160         driver_unregister(&viodrv->driver);
 161 }
 162 EXPORT_SYMBOL(vio_unregister_driver);
 163
 164 /* vio_dev refcount hit 0 */
 165 static void __devinit vio_dev_release(struct device *dev)
 166 {
 167         /* XXX should free TCE table */
 168         of_node_put(dev->archdata.of_node);
 169         kfree(to_vio_dev(dev));
 170 }
 171
 172 /**
 173  * vio_register_device_node: - Register a new vio device.
 174  * @of_node:    The OF node for this device.
 175  *
 176  * Creates and initializes a vio_dev structure from the data in
 177  * of_node and adds it to the list of virtual devices.
 178  * Returns a pointer to the created vio_dev or NULL if node has
 179  * NULL device_type or compatible fields.
 180  */
 181 struct vio_dev * __devinit vio_register_device_node(struct device_node *of_node)
 182 {
 183         struct vio_dev *viodev;
 184         const unsigned int *unit_address;
 185
 186         /* we need the 'device_type' property, in order to match with drivers */
 187         if (of_node->type == NULL) {
 188                 printk(KERN_WARNING "%s: node %s missing 'device_type'\n",
 189                                 __FUNCTION__,
 190                                 of_node->name ? of_node->name : "<unknown>");
 191                 return NULL;
 192         }
 193
 194         unit_address = of_get_property(of_node, "reg", NULL);
 195         if (unit_address == NULL) {
 196                 printk(KERN_WARNING "%s: node %s missing 'reg'\n",
 197                                 __FUNCTION__,
 198                                 of_node->name ? of_node->name : "<unknown>");
 199                 return NULL;
 200         }
 201
 202         /* allocate a vio_dev for this node */
 203         viodev = kzalloc(sizeof(struct vio_dev), GFP_KERNEL);
 204         if (viodev == NULL)
 205                 return NULL;
 206
 207         viodev->irq = irq_of_parse_and_map(of_node, 0);
 208
 209         snprintf(viodev->dev.bus_id, BUS_ID_SIZE, "%x", *unit_address);
 210         viodev->name = of_node->name;
 211         viodev->type = of_node->type;
 212         viodev->unit_address = *unit_address;
 213         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
 214                 unit_address = of_get_property(of_node,
 215                                 "linux,unit_address", NULL);
 216                 if (unit_address != NULL)
 217                         viodev->unit_address = *unit_address;
 218         }
 219         viodev->dev.archdata.of_node = of_node_get(of_node);
 220         viodev->dev.archdata.dma_ops = &dma_iommu_ops;
 221         viodev->dev.archdata.dma_data = vio_build_iommu_table(viodev);
 222         viodev->dev.archdata.numa_node = of_node_to_nid(of_node);
 223
 224         /* init generic 'struct device' fields: */
 225         viodev->dev.parent = &vio_bus_device.dev;
 226         viodev->dev.bus = &vio_bus_type;
 227         viodev->dev.release = vio_dev_release;
 228
 229         /* register with generic device framework */
 230         if (device_register(&viodev->dev)) {
 231                 printk(KERN_ERR "%s: failed to register device %s\n",
 232                                 __FUNCTION__, viodev->dev.bus_id);
 233                 /* XXX free TCE table */
 234                 kfree(viodev);
 235                 return NULL;
 236         }
 237
 238         return viodev;
 239 }
 240 EXPORT_SYMBOL(vio_register_device_node);
 241
 242 /**
 243  * vio_bus_init: - Initialize the virtual IO bus
 244  */
 245 static int __init vio_bus_init(void)
 246 {
 247         int err;
 248         struct device_node *node_vroot;
 249
 250         err = bus_register(&vio_bus_type);
 251         if (err) {
 252                 printk(KERN_ERR "failed to register VIO bus\n");
 253                 return err;
 254         }
 255
 256         /*
 257          * The fake parent of all vio devices, just to give us
 258          * a nice directory
 259          */
 260         err = device_register(&vio_bus_device.dev);
 261         if (err) {
 262                 printk(KERN_WARNING "%s: device_register returned %i\n",
 263                                 __FUNCTION__, err);
 264                 return err;
 265         }
 266
 267         node_vroot = of_find_node_by_name(NULL, "vdevice");
 268         if (node_vroot) {
 269                 struct device_node *of_node;
 270
 271                 /*
 272                  * Create struct vio_devices for each virtual device in
 273                  * the device tree. Drivers will associate with them later.
 274                  */
 275                 for (of_node = node_vroot->child; of_node != NULL;
 276                                 of_node = of_node->sibling)
 277                         vio_register_device_node(of_node);
 278                 of_node_put(node_vroot);
 279         }
 280
 281         return 0;
 282 }
 283 __initcall(vio_bus_init);
 284
 285 static ssize_t name_show(struct device *dev,
 286                 struct device_attribute *attr, char *buf)
 287 {
 288         return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
 289 }
 290
 291 static ssize_t devspec_show(struct device *dev,
 292                 struct device_attribute *attr, char *buf)
 293 {
 294         struct device_node *of_node = dev->archdata.of_node;
 295
 296         return sprintf(buf, "%s\n", of_node ? of_node->full_name : "none");
 297 }
 298
 299 static struct device_attribute vio_dev_attrs[] = {
 300         __ATTR_RO(name),
 301         __ATTR_RO(devspec),
 302         __ATTR_NULL
 303 };
 304
 305 void __devinit vio_unregister_device(struct vio_dev *viodev)
 306 {
 307         device_unregister(&viodev->dev);
 308 }
 309 EXPORT_SYMBOL(vio_unregister_device);
 310
 311 static int vio_bus_match(struct device *dev, struct device_driver *drv)
 312 {
 313         const struct vio_dev *vio_dev = to_vio_dev(dev);
 314         struct vio_driver *vio_drv = to_vio_driver(drv);
 315         const struct vio_device_id *ids = vio_drv->id_table;
 316
 317         return (ids != NULL) && (vio_match_device(ids, vio_dev) != NULL);
 318 }
 319
 320 static int vio_hotplug(struct device *dev, struct kobj_uevent_env *env)
 321 {
 322         const struct vio_dev *vio_dev = to_vio_dev(dev);
 323         struct device_node *dn;
 324         const char *cp;
 325
 326         dn = dev->archdata.of_node;
 327         if (!dn)
 328                 return -ENODEV;
 329         cp = of_get_property(dn, "compatible", NULL);
 330         if (!cp)
 331                 return -ENODEV;
 332
 333         add_uevent_var(env, "MODALIAS=vio:T%sS%s", vio_dev->type, cp);
 334         return 0;
 335 }
 336
 337 static struct bus_type vio_bus_type = {
 338         .name = "vio",
 339         .dev_attrs = vio_dev_attrs,
 340         .uevent = vio_hotplug,
 341         .match = vio_bus_match,
 342         .probe = vio_bus_probe,
 343         .remove = vio_bus_remove,
 344 };
 345
 346 /**
 347  * vio_get_attribute: - get attribute for virtual device
 348  * @vdev:       The vio device to get property.
 349  * @which:      The property/attribute to be extracted.
 350  * @length:     Pointer to length of returned data size (unused if NULL).
 351  *
 352  * Calls prom.c's of_get_property() to return the value of the
 353  * attribute specified by @which
 354 */
 355 const void *vio_get_attribute(struct vio_dev *vdev, char *which, int *length)
 356 {
 357         return of_get_property(vdev->dev.archdata.of_node, which, length);
 358 }
 359 EXPORT_SYMBOL(vio_get_attribute);
 360
 361 #ifdef CONFIG_PPC_PSERIES
 362 /* vio_find_name() - internal because only vio.c knows how we formatted the
 363  * kobject name
 364  * XXX once vio_bus_type.devices is actually used as a kset in
 365  * drivers/base/bus.c, this function should be removed in favor of
 366  * "device_find(kobj_name, &vio_bus_type)"
 367  */
 368 static struct vio_dev *vio_find_name(const char *kobj_name)
 369 {
 370         struct kobject *found;
 371
 372         found = kset_find_obj(&devices_subsys, kobj_name);
 373         if (!found)
 374                 return NULL;
 375
 376         return to_vio_dev(container_of(found, struct device, kobj));
 377 }
 378
 379 /**
 380  * vio_find_node - find an already-registered vio_dev
 381  * @vnode: device_node of the virtual device we're looking for
 382  */
 383 struct vio_dev *vio_find_node(struct device_node *vnode)
 384 {
 385         const uint32_t *unit_address;
 386         char kobj_name[BUS_ID_SIZE];
 387
 388         /* construct the kobject name from the device node */
 389         unit_address = of_get_property(vnode, "reg", NULL);
 390         if (!unit_address)
 391                 return NULL;
 392         snprintf(kobj_name, BUS_ID_SIZE, "%x", *unit_address);
 393
 394         return vio_find_name(kobj_name);
 395 }
 396 EXPORT_SYMBOL(vio_find_node);
 397
 398 int vio_enable_interrupts(struct vio_dev *dev)
 399 {
 400         int rc = h_vio_signal(dev->unit_address, VIO_IRQ_ENABLE);
 401         if (rc != H_SUCCESS)
 402                 printk(KERN_ERR "vio: Error 0x%x enabling interrupts\n", rc);
 403         return rc;
 404 }
 405 EXPORT_SYMBOL(vio_enable_interrupts);
 406
 407 int vio_disable_interrupts(struct vio_dev *dev)
 408 {
 409         int rc = h_vio_signal(dev->unit_address, VIO_IRQ_DISABLE);
 410         if (rc != H_SUCCESS)
 411                 printk(KERN_ERR "vio: Error 0x%x disabling interrupts\n", rc);
 412         return rc;
 413 }
 414 EXPORT_SYMBOL(vio_disable_interrupts);
 415 #endif /* CONFIG_PPC_PSERIES */