1 /* vio.c: Virtual I/O channel devices probing infrastructure.
2  *
3  *    Copyright (c) 2003-2005 IBM Corp.
4  *     Dave Engebretsen engebret@us.ibm.com
5  *     Santiago Leon santil@us.ibm.com
6  *     Hollis Blanchard <hollisb@us.ibm.com>
7  *     Stephen Rothwell
8  *
9  * Adapted to sparc64 by David S. Miller davem@davemloft.net
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/irq.h>
15 #include <linux/init.h>
16 
17 #include <asm/mdesc.h>
18 #include <asm/vio.h>
19 
vio_match_device(const struct vio_device_id * matches,const struct vio_dev * dev)20 static const struct vio_device_id *vio_match_device(
21 	const struct vio_device_id *matches,
22 	const struct vio_dev *dev)
23 {
24 	const char *type, *compat;
25 	int len;
26 
27 	type = dev->type;
28 	compat = dev->compat;
29 	len = dev->compat_len;
30 
31 	while (matches->type[0] || matches->compat[0]) {
32 		int match = 1;
33 		if (matches->type[0])
34 			match &= !strcmp(matches->type, type);
35 
36 		if (matches->compat[0]) {
37 			match &= len &&
38 				of_find_in_proplist(compat, matches->compat, len);
39 		}
40 		if (match)
41 			return matches;
42 		matches++;
43 	}
44 	return NULL;
45 }
46 
vio_bus_match(struct device * dev,struct device_driver * drv)47 static int vio_bus_match(struct device *dev, struct device_driver *drv)
48 {
49 	struct vio_dev *vio_dev = to_vio_dev(dev);
50 	struct vio_driver *vio_drv = to_vio_driver(drv);
51 	const struct vio_device_id *matches = vio_drv->id_table;
52 
53 	if (!matches)
54 		return 0;
55 
56 	return vio_match_device(matches, vio_dev) != NULL;
57 }
58 
vio_device_probe(struct device * dev)59 static int vio_device_probe(struct device *dev)
60 {
61 	struct vio_dev *vdev = to_vio_dev(dev);
62 	struct vio_driver *drv = to_vio_driver(dev->driver);
63 	const struct vio_device_id *id;
64 	int error = -ENODEV;
65 
66 	if (drv->probe) {
67 		id = vio_match_device(drv->id_table, vdev);
68 		if (id)
69 			error = drv->probe(vdev, id);
70 	}
71 
72 	return error;
73 }
74 
vio_device_remove(struct device * dev)75 static int vio_device_remove(struct device *dev)
76 {
77 	struct vio_dev *vdev = to_vio_dev(dev);
78 	struct vio_driver *drv = to_vio_driver(dev->driver);
79 
80 	if (drv->remove)
81 		return drv->remove(vdev);
82 
83 	return 1;
84 }
85 
devspec_show(struct device * dev,struct device_attribute * attr,char * buf)86 static ssize_t devspec_show(struct device *dev,
87 		struct device_attribute *attr, char *buf)
88 {
89 	struct vio_dev *vdev = to_vio_dev(dev);
90 	const char *str = "none";
91 
92 	if (!strcmp(vdev->type, "vnet-port"))
93 		str = "vnet";
94 	else if (!strcmp(vdev->type, "vdc-port"))
95 		str = "vdisk";
96 
97 	return sprintf(buf, "%s\n", str);
98 }
99 
type_show(struct device * dev,struct device_attribute * attr,char * buf)100 static ssize_t type_show(struct device *dev,
101 		struct device_attribute *attr, char *buf)
102 {
103 	struct vio_dev *vdev = to_vio_dev(dev);
104 	return sprintf(buf, "%s\n", vdev->type);
105 }
106 
107 static struct device_attribute vio_dev_attrs[] = {
108 	__ATTR_RO(devspec),
109 	__ATTR_RO(type),
110 	__ATTR_NULL
111 };
112 
113 static struct bus_type vio_bus_type = {
114 	.name		= "vio",
115 	.dev_attrs	= vio_dev_attrs,
116 	.match		= vio_bus_match,
117 	.probe		= vio_device_probe,
118 	.remove		= vio_device_remove,
119 };
120 
vio_register_driver(struct vio_driver * viodrv)121 int vio_register_driver(struct vio_driver *viodrv)
122 {
123 	viodrv->driver.bus = &vio_bus_type;
124 
125 	return driver_register(&viodrv->driver);
126 }
127 EXPORT_SYMBOL(vio_register_driver);
128 
vio_unregister_driver(struct vio_driver * viodrv)129 void vio_unregister_driver(struct vio_driver *viodrv)
130 {
131 	driver_unregister(&viodrv->driver);
132 }
133 EXPORT_SYMBOL(vio_unregister_driver);
134 
vio_dev_release(struct device * dev)135 static void vio_dev_release(struct device *dev)
136 {
137 	kfree(to_vio_dev(dev));
138 }
139 
140 static ssize_t
show_pciobppath_attr(struct device * dev,struct device_attribute * attr,char * buf)141 show_pciobppath_attr(struct device *dev, struct device_attribute *attr,
142 		     char *buf)
143 {
144 	struct vio_dev *vdev;
145 	struct device_node *dp;
146 
147 	vdev = to_vio_dev(dev);
148 	dp = vdev->dp;
149 
150 	return snprintf (buf, PAGE_SIZE, "%s\n", dp->full_name);
151 }
152 
153 static DEVICE_ATTR(obppath, S_IRUSR | S_IRGRP | S_IROTH,
154 		   show_pciobppath_attr, NULL);
155 
156 static struct device_node *cdev_node;
157 
158 static struct vio_dev *root_vdev;
159 static u64 cdev_cfg_handle;
160 
vio_fill_channel_info(struct mdesc_handle * hp,u64 mp,struct vio_dev * vdev)161 static void vio_fill_channel_info(struct mdesc_handle *hp, u64 mp,
162 				  struct vio_dev *vdev)
163 {
164 	u64 a;
165 
166 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
167 		const u64 *chan_id;
168 		const u64 *irq;
169 		u64 target;
170 
171 		target = mdesc_arc_target(hp, a);
172 
173 		irq = mdesc_get_property(hp, target, "tx-ino", NULL);
174 		if (irq)
175 			vdev->tx_irq = sun4v_build_virq(cdev_cfg_handle, *irq);
176 
177 		irq = mdesc_get_property(hp, target, "rx-ino", NULL);
178 		if (irq)
179 			vdev->rx_irq = sun4v_build_virq(cdev_cfg_handle, *irq);
180 
181 		chan_id = mdesc_get_property(hp, target, "id", NULL);
182 		if (chan_id)
183 			vdev->channel_id = *chan_id;
184 	}
185 }
186 
vio_create_one(struct mdesc_handle * hp,u64 mp,struct device * parent)187 static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
188 				      struct device *parent)
189 {
190 	const char *type, *compat, *bus_id_name;
191 	struct device_node *dp;
192 	struct vio_dev *vdev;
193 	int err, tlen, clen;
194 	const u64 *id, *cfg_handle;
195 	u64 a;
196 
197 	type = mdesc_get_property(hp, mp, "device-type", &tlen);
198 	if (!type) {
199 		type = mdesc_get_property(hp, mp, "name", &tlen);
200 		if (!type) {
201 			type = mdesc_node_name(hp, mp);
202 			tlen = strlen(type) + 1;
203 		}
204 	}
205 	if (tlen > VIO_MAX_TYPE_LEN) {
206 		printk(KERN_ERR "VIO: Type string [%s] is too long.\n",
207 		       type);
208 		return NULL;
209 	}
210 
211 	id = mdesc_get_property(hp, mp, "id", NULL);
212 
213 	cfg_handle = NULL;
214 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
215 		u64 target;
216 
217 		target = mdesc_arc_target(hp, a);
218 		cfg_handle = mdesc_get_property(hp, target,
219 						"cfg-handle", NULL);
220 		if (cfg_handle)
221 			break;
222 	}
223 
224 	bus_id_name = type;
225 	if (!strcmp(type, "domain-services-port"))
226 		bus_id_name = "ds";
227 
228 	/*
229 	 * 20 char is the old driver-core name size limit, which is no more.
230 	 * This check can probably be removed after review and possible
231 	 * adaption of the vio users name length handling.
232 	 */
233 	if (strlen(bus_id_name) >= 20 - 4) {
234 		printk(KERN_ERR "VIO: bus_id_name [%s] is too long.\n",
235 		       bus_id_name);
236 		return NULL;
237 	}
238 
239 	compat = mdesc_get_property(hp, mp, "device-type", &clen);
240 	if (!compat) {
241 		clen = 0;
242 	} else if (clen > VIO_MAX_COMPAT_LEN) {
243 		printk(KERN_ERR "VIO: Compat len %d for [%s] is too long.\n",
244 		       clen, type);
245 		return NULL;
246 	}
247 
248 	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
249 	if (!vdev) {
250 		printk(KERN_ERR "VIO: Could not allocate vio_dev\n");
251 		return NULL;
252 	}
253 
254 	vdev->mp = mp;
255 	memcpy(vdev->type, type, tlen);
256 	if (compat)
257 		memcpy(vdev->compat, compat, clen);
258 	else
259 		memset(vdev->compat, 0, sizeof(vdev->compat));
260 	vdev->compat_len = clen;
261 
262 	vdev->channel_id = ~0UL;
263 	vdev->tx_irq = ~0;
264 	vdev->rx_irq = ~0;
265 
266 	vio_fill_channel_info(hp, mp, vdev);
267 
268 	if (!id) {
269 		dev_set_name(&vdev->dev, "%s", bus_id_name);
270 		vdev->dev_no = ~(u64)0;
271 	} else if (!cfg_handle) {
272 		dev_set_name(&vdev->dev, "%s-%llu", bus_id_name, *id);
273 		vdev->dev_no = *id;
274 	} else {
275 		dev_set_name(&vdev->dev, "%s-%llu-%llu", bus_id_name,
276 			     *cfg_handle, *id);
277 		vdev->dev_no = *cfg_handle;
278 	}
279 
280 	vdev->dev.parent = parent;
281 	vdev->dev.bus = &vio_bus_type;
282 	vdev->dev.release = vio_dev_release;
283 
284 	if (parent == NULL) {
285 		dp = cdev_node;
286 	} else if (to_vio_dev(parent) == root_vdev) {
287 		dp = of_get_next_child(cdev_node, NULL);
288 		while (dp) {
289 			if (!strcmp(dp->type, type))
290 				break;
291 
292 			dp = of_get_next_child(cdev_node, dp);
293 		}
294 	} else {
295 		dp = to_vio_dev(parent)->dp;
296 	}
297 	vdev->dp = dp;
298 
299 	printk(KERN_INFO "VIO: Adding device %s\n", dev_name(&vdev->dev));
300 
301 	err = device_register(&vdev->dev);
302 	if (err) {
303 		printk(KERN_ERR "VIO: Could not register device %s, err=%d\n",
304 		       dev_name(&vdev->dev), err);
305 		kfree(vdev);
306 		return NULL;
307 	}
308 	if (vdev->dp)
309 		err = sysfs_create_file(&vdev->dev.kobj,
310 					&dev_attr_obppath.attr);
311 
312 	return vdev;
313 }
314 
vio_add(struct mdesc_handle * hp,u64 node)315 static void vio_add(struct mdesc_handle *hp, u64 node)
316 {
317 	(void) vio_create_one(hp, node, &root_vdev->dev);
318 }
319 
vio_md_node_match(struct device * dev,void * arg)320 static int vio_md_node_match(struct device *dev, void *arg)
321 {
322 	struct vio_dev *vdev = to_vio_dev(dev);
323 
324 	if (vdev->mp == (u64) arg)
325 		return 1;
326 
327 	return 0;
328 }
329 
vio_remove(struct mdesc_handle * hp,u64 node)330 static void vio_remove(struct mdesc_handle *hp, u64 node)
331 {
332 	struct device *dev;
333 
334 	dev = device_find_child(&root_vdev->dev, (void *) node,
335 				vio_md_node_match);
336 	if (dev) {
337 		printk(KERN_INFO "VIO: Removing device %s\n", dev_name(dev));
338 
339 		device_unregister(dev);
340 	}
341 }
342 
343 static struct mdesc_notifier_client vio_device_notifier = {
344 	.add		= vio_add,
345 	.remove		= vio_remove,
346 	.node_name	= "virtual-device-port",
347 };
348 
349 /* We are only interested in domain service ports under the
350  * "domain-services" node.  On control nodes there is another port
351  * under "openboot" that we should not mess with as aparently that is
352  * reserved exclusively for OBP use.
353  */
vio_add_ds(struct mdesc_handle * hp,u64 node)354 static void vio_add_ds(struct mdesc_handle *hp, u64 node)
355 {
356 	int found;
357 	u64 a;
358 
359 	found = 0;
360 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
361 		u64 target = mdesc_arc_target(hp, a);
362 		const char *name = mdesc_node_name(hp, target);
363 
364 		if (!strcmp(name, "domain-services")) {
365 			found = 1;
366 			break;
367 		}
368 	}
369 
370 	if (found)
371 		(void) vio_create_one(hp, node, &root_vdev->dev);
372 }
373 
374 static struct mdesc_notifier_client vio_ds_notifier = {
375 	.add		= vio_add_ds,
376 	.remove		= vio_remove,
377 	.node_name	= "domain-services-port",
378 };
379 
380 static const char *channel_devices_node = "channel-devices";
381 static const char *channel_devices_compat = "SUNW,sun4v-channel-devices";
382 static const char *cfg_handle_prop = "cfg-handle";
383 
vio_init(void)384 static int __init vio_init(void)
385 {
386 	struct mdesc_handle *hp;
387 	const char *compat;
388 	const u64 *cfg_handle;
389 	int err, len;
390 	u64 root;
391 
392 	err = bus_register(&vio_bus_type);
393 	if (err) {
394 		printk(KERN_ERR "VIO: Could not register bus type err=%d\n",
395 		       err);
396 		return err;
397 	}
398 
399 	hp = mdesc_grab();
400 	if (!hp)
401 		return 0;
402 
403 	root = mdesc_node_by_name(hp, MDESC_NODE_NULL, channel_devices_node);
404 	if (root == MDESC_NODE_NULL) {
405 		printk(KERN_INFO "VIO: No channel-devices MDESC node.\n");
406 		mdesc_release(hp);
407 		return 0;
408 	}
409 
410 	cdev_node = of_find_node_by_name(NULL, "channel-devices");
411 	err = -ENODEV;
412 	if (!cdev_node) {
413 		printk(KERN_INFO "VIO: No channel-devices OBP node.\n");
414 		goto out_release;
415 	}
416 
417 	compat = mdesc_get_property(hp, root, "compatible", &len);
418 	if (!compat) {
419 		printk(KERN_ERR "VIO: Channel devices lacks compatible "
420 		       "property\n");
421 		goto out_release;
422 	}
423 	if (!of_find_in_proplist(compat, channel_devices_compat, len)) {
424 		printk(KERN_ERR "VIO: Channel devices node lacks (%s) "
425 		       "compat entry.\n", channel_devices_compat);
426 		goto out_release;
427 	}
428 
429 	cfg_handle = mdesc_get_property(hp, root, cfg_handle_prop, NULL);
430 	if (!cfg_handle) {
431 		printk(KERN_ERR "VIO: Channel devices lacks %s property\n",
432 		       cfg_handle_prop);
433 		goto out_release;
434 	}
435 
436 	cdev_cfg_handle = *cfg_handle;
437 
438 	root_vdev = vio_create_one(hp, root, NULL);
439 	err = -ENODEV;
440 	if (!root_vdev) {
441 		printk(KERN_ERR "VIO: Coult not create root device.\n");
442 		goto out_release;
443 	}
444 
445 	mdesc_register_notifier(&vio_device_notifier);
446 	mdesc_register_notifier(&vio_ds_notifier);
447 
448 	mdesc_release(hp);
449 
450 	return err;
451 
452 out_release:
453 	mdesc_release(hp);
454 	return err;
455 }
456 
457 postcore_initcall(vio_init);
458