xref: /openbmc/linux/arch/sparc/kernel/vio.c (revision f7018c21)
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/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),
111 	__ATTR_NULL
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 }
132 EXPORT_SYMBOL(__vio_register_driver);
133 
134 void vio_unregister_driver(struct vio_driver *viodrv)
135 {
136 	driver_unregister(&viodrv->driver);
137 }
138 EXPORT_SYMBOL(vio_unregister_driver);
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 
171 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
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;
219 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
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 		put_device(dev);
346 	}
347 }
348 
349 static struct mdesc_notifier_client vio_device_notifier = {
350 	.add		= vio_add,
351 	.remove		= vio_remove,
352 	.node_name	= "virtual-device-port",
353 };
354 
355 /* We are only interested in domain service ports under the
356  * "domain-services" node.  On control nodes there is another port
357  * under "openboot" that we should not mess with as aparently that is
358  * reserved exclusively for OBP use.
359  */
360 static void vio_add_ds(struct mdesc_handle *hp, u64 node)
361 {
362 	int found;
363 	u64 a;
364 
365 	found = 0;
366 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
367 		u64 target = mdesc_arc_target(hp, a);
368 		const char *name = mdesc_node_name(hp, target);
369 
370 		if (!strcmp(name, "domain-services")) {
371 			found = 1;
372 			break;
373 		}
374 	}
375 
376 	if (found)
377 		(void) vio_create_one(hp, node, &root_vdev->dev);
378 }
379 
380 static struct mdesc_notifier_client vio_ds_notifier = {
381 	.add		= vio_add_ds,
382 	.remove		= vio_remove,
383 	.node_name	= "domain-services-port",
384 };
385 
386 static const char *channel_devices_node = "channel-devices";
387 static const char *channel_devices_compat = "SUNW,sun4v-channel-devices";
388 static const char *cfg_handle_prop = "cfg-handle";
389 
390 static int __init vio_init(void)
391 {
392 	struct mdesc_handle *hp;
393 	const char *compat;
394 	const u64 *cfg_handle;
395 	int err, len;
396 	u64 root;
397 
398 	err = bus_register(&vio_bus_type);
399 	if (err) {
400 		printk(KERN_ERR "VIO: Could not register bus type err=%d\n",
401 		       err);
402 		return err;
403 	}
404 
405 	hp = mdesc_grab();
406 	if (!hp)
407 		return 0;
408 
409 	root = mdesc_node_by_name(hp, MDESC_NODE_NULL, channel_devices_node);
410 	if (root == MDESC_NODE_NULL) {
411 		printk(KERN_INFO "VIO: No channel-devices MDESC node.\n");
412 		mdesc_release(hp);
413 		return 0;
414 	}
415 
416 	cdev_node = of_find_node_by_name(NULL, "channel-devices");
417 	err = -ENODEV;
418 	if (!cdev_node) {
419 		printk(KERN_INFO "VIO: No channel-devices OBP node.\n");
420 		goto out_release;
421 	}
422 
423 	compat = mdesc_get_property(hp, root, "compatible", &len);
424 	if (!compat) {
425 		printk(KERN_ERR "VIO: Channel devices lacks compatible "
426 		       "property\n");
427 		goto out_release;
428 	}
429 	if (!of_find_in_proplist(compat, channel_devices_compat, len)) {
430 		printk(KERN_ERR "VIO: Channel devices node lacks (%s) "
431 		       "compat entry.\n", channel_devices_compat);
432 		goto out_release;
433 	}
434 
435 	cfg_handle = mdesc_get_property(hp, root, cfg_handle_prop, NULL);
436 	if (!cfg_handle) {
437 		printk(KERN_ERR "VIO: Channel devices lacks %s property\n",
438 		       cfg_handle_prop);
439 		goto out_release;
440 	}
441 
442 	cdev_cfg_handle = *cfg_handle;
443 
444 	root_vdev = vio_create_one(hp, root, NULL);
445 	err = -ENODEV;
446 	if (!root_vdev) {
447 		printk(KERN_ERR "VIO: Could not create root device.\n");
448 		goto out_release;
449 	}
450 
451 	mdesc_register_notifier(&vio_device_notifier);
452 	mdesc_register_notifier(&vio_ds_notifier);
453 
454 	mdesc_release(hp);
455 
456 	return err;
457 
458 out_release:
459 	mdesc_release(hp);
460 	return err;
461 }
462 
463 postcore_initcall(vio_init);
464