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vio.c
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1 /* vio.c: Virtual I/O channel devices probing infrastructure.
2  *
3  * Copyright (c) 2003-2005 IBM Corp.
4  * Dave Engebretsen [email protected]
5  * Santiago Leon [email protected]
6  * Hollis Blanchard <[email protected]>
7  * Stephen Rothwell
8  *
9  * Adapted to sparc64 by David S. Miller [email protected]
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/irq.h>
15 #include <linux/export.h>
16 #include <linux/init.h>
17 
18 #include <asm/mdesc.h>
19 #include <asm/vio.h>
20 
21 static const struct vio_device_id *vio_match_device(
22  const struct vio_device_id *matches,
23  const struct vio_dev *dev)
24 {
25  const char *type, *compat;
26  int len;
27 
28  type = dev->type;
29  compat = dev->compat;
30  len = dev->compat_len;
31 
32  while (matches->type[0] || matches->compat[0]) {
33  int match = 1;
34  if (matches->type[0])
35  match &= !strcmp(matches->type, type);
36 
37  if (matches->compat[0]) {
38  match &= len &&
39  of_find_in_proplist(compat, matches->compat, len);
40  }
41  if (match)
42  return matches;
43  matches++;
44  }
45  return NULL;
46 }
47 
48 static int vio_bus_match(struct device *dev, struct device_driver *drv)
49 {
50  struct vio_dev *vio_dev = to_vio_dev(dev);
51  struct vio_driver *vio_drv = to_vio_driver(drv);
52  const struct vio_device_id *matches = vio_drv->id_table;
53 
54  if (!matches)
55  return 0;
56 
57  return vio_match_device(matches, vio_dev) != NULL;
58 }
59 
60 static int vio_device_probe(struct device *dev)
61 {
62  struct vio_dev *vdev = to_vio_dev(dev);
63  struct vio_driver *drv = to_vio_driver(dev->driver);
64  const struct vio_device_id *id;
65  int error = -ENODEV;
66 
67  if (drv->probe) {
68  id = vio_match_device(drv->id_table, vdev);
69  if (id)
70  error = drv->probe(vdev, id);
71  }
72 
73  return error;
74 }
75 
76 static int vio_device_remove(struct device *dev)
77 {
78  struct vio_dev *vdev = to_vio_dev(dev);
79  struct vio_driver *drv = to_vio_driver(dev->driver);
80 
81  if (drv->remove)
82  return drv->remove(vdev);
83 
84  return 1;
85 }
86 
87 static ssize_t devspec_show(struct device *dev,
88  struct device_attribute *attr, char *buf)
89 {
90  struct vio_dev *vdev = to_vio_dev(dev);
91  const char *str = "none";
92 
93  if (!strcmp(vdev->type, "vnet-port"))
94  str = "vnet";
95  else if (!strcmp(vdev->type, "vdc-port"))
96  str = "vdisk";
97 
98  return sprintf(buf, "%s\n", str);
99 }
100 
101 static ssize_t type_show(struct device *dev,
102  struct device_attribute *attr, char *buf)
103 {
104  struct vio_dev *vdev = to_vio_dev(dev);
105  return sprintf(buf, "%s\n", vdev->type);
106 }
107 
108 static struct device_attribute vio_dev_attrs[] = {
109  __ATTR_RO(devspec),
110  __ATTR_RO(type),
112 };
113 
114 static struct bus_type vio_bus_type = {
115  .name = "vio",
116  .dev_attrs = vio_dev_attrs,
117  .match = vio_bus_match,
118  .probe = vio_device_probe,
119  .remove = vio_device_remove,
120 };
121 
122 int __vio_register_driver(struct vio_driver *viodrv, struct module *owner,
123  const char *mod_name)
124 {
125  viodrv->driver.bus = &vio_bus_type;
126  viodrv->driver.name = viodrv->name;
127  viodrv->driver.owner = owner;
128  viodrv->driver.mod_name = mod_name;
129 
130  return driver_register(&viodrv->driver);
131 }
133 
134 void vio_unregister_driver(struct vio_driver *viodrv)
135 {
136  driver_unregister(&viodrv->driver);
137 }
139 
140 static void vio_dev_release(struct device *dev)
141 {
142  kfree(to_vio_dev(dev));
143 }
144 
145 static ssize_t
146 show_pciobppath_attr(struct device *dev, struct device_attribute *attr,
147  char *buf)
148 {
149  struct vio_dev *vdev;
150  struct device_node *dp;
151 
152  vdev = to_vio_dev(dev);
153  dp = vdev->dp;
154 
155  return snprintf (buf, PAGE_SIZE, "%s\n", dp->full_name);
156 }
157 
158 static DEVICE_ATTR(obppath, S_IRUSR | S_IRGRP | S_IROTH,
159  show_pciobppath_attr, NULL);
160 
161 static struct device_node *cdev_node;
162 
163 static struct vio_dev *root_vdev;
164 static u64 cdev_cfg_handle;
165 
166 static void vio_fill_channel_info(struct mdesc_handle *hp, u64 mp,
167  struct vio_dev *vdev)
168 {
169  u64 a;
170 
172  const u64 *chan_id;
173  const u64 *irq;
174  u64 target;
175 
176  target = mdesc_arc_target(hp, a);
177 
178  irq = mdesc_get_property(hp, target, "tx-ino", NULL);
179  if (irq)
180  vdev->tx_irq = sun4v_build_virq(cdev_cfg_handle, *irq);
181 
182  irq = mdesc_get_property(hp, target, "rx-ino", NULL);
183  if (irq)
184  vdev->rx_irq = sun4v_build_virq(cdev_cfg_handle, *irq);
185 
186  chan_id = mdesc_get_property(hp, target, "id", NULL);
187  if (chan_id)
188  vdev->channel_id = *chan_id;
189  }
190 }
191 
192 static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
193  struct device *parent)
194 {
195  const char *type, *compat, *bus_id_name;
196  struct device_node *dp;
197  struct vio_dev *vdev;
198  int err, tlen, clen;
199  const u64 *id, *cfg_handle;
200  u64 a;
201 
202  type = mdesc_get_property(hp, mp, "device-type", &tlen);
203  if (!type) {
204  type = mdesc_get_property(hp, mp, "name", &tlen);
205  if (!type) {
206  type = mdesc_node_name(hp, mp);
207  tlen = strlen(type) + 1;
208  }
209  }
210  if (tlen > VIO_MAX_TYPE_LEN) {
211  printk(KERN_ERR "VIO: Type string [%s] is too long.\n",
212  type);
213  return NULL;
214  }
215 
216  id = mdesc_get_property(hp, mp, "id", NULL);
217 
218  cfg_handle = NULL;
220  u64 target;
221 
222  target = mdesc_arc_target(hp, a);
223  cfg_handle = mdesc_get_property(hp, target,
224  "cfg-handle", NULL);
225  if (cfg_handle)
226  break;
227  }
228 
229  bus_id_name = type;
230  if (!strcmp(type, "domain-services-port"))
231  bus_id_name = "ds";
232 
233  /*
234  * 20 char is the old driver-core name size limit, which is no more.
235  * This check can probably be removed after review and possible
236  * adaption of the vio users name length handling.
237  */
238  if (strlen(bus_id_name) >= 20 - 4) {
239  printk(KERN_ERR "VIO: bus_id_name [%s] is too long.\n",
240  bus_id_name);
241  return NULL;
242  }
243 
244  compat = mdesc_get_property(hp, mp, "device-type", &clen);
245  if (!compat) {
246  clen = 0;
247  } else if (clen > VIO_MAX_COMPAT_LEN) {
248  printk(KERN_ERR "VIO: Compat len %d for [%s] is too long.\n",
249  clen, type);
250  return NULL;
251  }
252 
253  vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
254  if (!vdev) {
255  printk(KERN_ERR "VIO: Could not allocate vio_dev\n");
256  return NULL;
257  }
258 
259  vdev->mp = mp;
260  memcpy(vdev->type, type, tlen);
261  if (compat)
262  memcpy(vdev->compat, compat, clen);
263  else
264  memset(vdev->compat, 0, sizeof(vdev->compat));
265  vdev->compat_len = clen;
266 
267  vdev->channel_id = ~0UL;
268  vdev->tx_irq = ~0;
269  vdev->rx_irq = ~0;
270 
271  vio_fill_channel_info(hp, mp, vdev);
272 
273  if (!id) {
274  dev_set_name(&vdev->dev, "%s", bus_id_name);
275  vdev->dev_no = ~(u64)0;
276  } else if (!cfg_handle) {
277  dev_set_name(&vdev->dev, "%s-%llu", bus_id_name, *id);
278  vdev->dev_no = *id;
279  } else {
280  dev_set_name(&vdev->dev, "%s-%llu-%llu", bus_id_name,
281  *cfg_handle, *id);
282  vdev->dev_no = *cfg_handle;
283  }
284 
285  vdev->dev.parent = parent;
286  vdev->dev.bus = &vio_bus_type;
287  vdev->dev.release = vio_dev_release;
288 
289  if (parent == NULL) {
290  dp = cdev_node;
291  } else if (to_vio_dev(parent) == root_vdev) {
292  dp = of_get_next_child(cdev_node, NULL);
293  while (dp) {
294  if (!strcmp(dp->type, type))
295  break;
296 
297  dp = of_get_next_child(cdev_node, dp);
298  }
299  } else {
300  dp = to_vio_dev(parent)->dp;
301  }
302  vdev->dp = dp;
303 
304  printk(KERN_INFO "VIO: Adding device %s\n", dev_name(&vdev->dev));
305 
306  err = device_register(&vdev->dev);
307  if (err) {
308  printk(KERN_ERR "VIO: Could not register device %s, err=%d\n",
309  dev_name(&vdev->dev), err);
310  kfree(vdev);
311  return NULL;
312  }
313  if (vdev->dp)
314  err = sysfs_create_file(&vdev->dev.kobj,
315  &dev_attr_obppath.attr);
316 
317  return vdev;
318 }
319 
320 static void vio_add(struct mdesc_handle *hp, u64 node)
321 {
322  (void) vio_create_one(hp, node, &root_vdev->dev);
323 }
324 
325 static int vio_md_node_match(struct device *dev, void *arg)
326 {
327  struct vio_dev *vdev = to_vio_dev(dev);
328 
329  if (vdev->mp == (u64) arg)
330  return 1;
331 
332  return 0;
333 }
334 
335 static void vio_remove(struct mdesc_handle *hp, u64 node)
336 {
337  struct device *dev;
338 
339  dev = device_find_child(&root_vdev->dev, (void *) node,
340  vio_md_node_match);
341  if (dev) {
342  printk(KERN_INFO "VIO: Removing device %s\n", dev_name(dev));
343 
344  device_unregister(dev);
345  }
346 }
347 
348 static struct mdesc_notifier_client vio_device_notifier = {
349  .add = vio_add,
350  .remove = vio_remove,
351  .node_name = "virtual-device-port",
352 };
353 
354 /* We are only interested in domain service ports under the
355  * "domain-services" node. On control nodes there is another port
356  * under "openboot" that we should not mess with as aparently that is
357  * reserved exclusively for OBP use.
358  */
359 static void vio_add_ds(struct mdesc_handle *hp, u64 node)
360 {
361  int found;
362  u64 a;
363 
364  found = 0;
366  u64 target = mdesc_arc_target(hp, a);
367  const char *name = mdesc_node_name(hp, target);
368 
369  if (!strcmp(name, "domain-services")) {
370  found = 1;
371  break;
372  }
373  }
374 
375  if (found)
376  (void) vio_create_one(hp, node, &root_vdev->dev);
377 }
378 
379 static struct mdesc_notifier_client vio_ds_notifier = {
380  .add = vio_add_ds,
381  .remove = vio_remove,
382  .node_name = "domain-services-port",
383 };
384 
385 static const char *channel_devices_node = "channel-devices";
386 static const char *channel_devices_compat = "SUNW,sun4v-channel-devices";
387 static const char *cfg_handle_prop = "cfg-handle";
388 
389 static int __init vio_init(void)
390 {
391  struct mdesc_handle *hp;
392  const char *compat;
393  const u64 *cfg_handle;
394  int err, len;
395  u64 root;
396 
397  err = bus_register(&vio_bus_type);
398  if (err) {
399  printk(KERN_ERR "VIO: Could not register bus type err=%d\n",
400  err);
401  return err;
402  }
403 
404  hp = mdesc_grab();
405  if (!hp)
406  return 0;
407 
408  root = mdesc_node_by_name(hp, MDESC_NODE_NULL, channel_devices_node);
409  if (root == MDESC_NODE_NULL) {
410  printk(KERN_INFO "VIO: No channel-devices MDESC node.\n");
411  mdesc_release(hp);
412  return 0;
413  }
414 
415  cdev_node = of_find_node_by_name(NULL, "channel-devices");
416  err = -ENODEV;
417  if (!cdev_node) {
418  printk(KERN_INFO "VIO: No channel-devices OBP node.\n");
419  goto out_release;
420  }
421 
422  compat = mdesc_get_property(hp, root, "compatible", &len);
423  if (!compat) {
424  printk(KERN_ERR "VIO: Channel devices lacks compatible "
425  "property\n");
426  goto out_release;
427  }
428  if (!of_find_in_proplist(compat, channel_devices_compat, len)) {
429  printk(KERN_ERR "VIO: Channel devices node lacks (%s) "
430  "compat entry.\n", channel_devices_compat);
431  goto out_release;
432  }
433 
434  cfg_handle = mdesc_get_property(hp, root, cfg_handle_prop, NULL);
435  if (!cfg_handle) {
436  printk(KERN_ERR "VIO: Channel devices lacks %s property\n",
437  cfg_handle_prop);
438  goto out_release;
439  }
440 
441  cdev_cfg_handle = *cfg_handle;
442 
443  root_vdev = vio_create_one(hp, root, NULL);
444  err = -ENODEV;
445  if (!root_vdev) {
446  printk(KERN_ERR "VIO: Could not create root device.\n");
447  goto out_release;
448  }
449 
450  mdesc_register_notifier(&vio_device_notifier);
451  mdesc_register_notifier(&vio_ds_notifier);
452 
453  mdesc_release(hp);
454 
455  return err;
456 
457 out_release:
458  mdesc_release(hp);
459  return err;
460 }
461 
462 postcore_initcall(vio_init);