xref: /linux/arch/sparc/kernel/vio.c (revision 805185b7c7a1069e407b6f7b3bc98e44d415f484)
1 // SPDX-License-Identifier: GPL-2.0
2 /* vio.c: Virtual I/O channel devices probing infrastructure.
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  * Adapted to sparc64 by David S. Miller davem@davemloft.net
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/string.h>
16 #include <linux/sysfs.h>
17 #include <linux/irq.h>
18 #include <linux/export.h>
19 #include <linux/init.h>
20 
21 #include <asm/mdesc.h>
22 #include <asm/vio.h>
23 
24 static const struct vio_device_id *vio_match_device(
25 	const struct vio_device_id *matches,
26 	const struct vio_dev *dev)
27 {
28 	const char *type, *compat;
29 	int len;
30 
31 	type = dev->type;
32 	compat = dev->compat;
33 	len = dev->compat_len;
34 
35 	while (matches->type[0] || matches->compat[0]) {
36 		int match = 1;
37 		if (matches->type[0])
38 			match &= !strcmp(matches->type, type);
39 
40 		if (matches->compat[0]) {
41 			match &= len &&
42 				of_find_in_proplist(compat, matches->compat, len);
43 		}
44 		if (match)
45 			return matches;
46 		matches++;
47 	}
48 	return NULL;
49 }
50 
51 static int vio_hotplug(const struct device *dev, struct kobj_uevent_env *env)
52 {
53 	const struct vio_dev *vio_dev = to_vio_dev(dev);
54 
55 	add_uevent_var(env, "MODALIAS=vio:T%sS%s", vio_dev->type, vio_dev->compat);
56 	return 0;
57 }
58 
59 static int vio_bus_match(struct device *dev, const struct device_driver *drv)
60 {
61 	struct vio_dev *vio_dev = to_vio_dev(dev);
62 	const struct vio_driver *vio_drv = to_vio_driver(drv);
63 	const struct vio_device_id *matches = vio_drv->id_table;
64 
65 	if (!matches)
66 		return 0;
67 
68 	return vio_match_device(matches, vio_dev) != NULL;
69 }
70 
71 static int vio_device_probe(struct device *dev)
72 {
73 	struct vio_dev *vdev = to_vio_dev(dev);
74 	struct vio_driver *drv = to_vio_driver(dev->driver);
75 	const struct vio_device_id *id;
76 
77 	if (!drv->probe)
78 		return -ENODEV;
79 
80 	id = vio_match_device(drv->id_table, vdev);
81 	if (!id)
82 		return -ENODEV;
83 
84 	/* alloc irqs (unless the driver specified not to) */
85 	if (!drv->no_irq) {
86 		if (vdev->tx_irq == 0 && vdev->tx_ino != ~0UL)
87 			vdev->tx_irq = sun4v_build_virq(vdev->cdev_handle,
88 							vdev->tx_ino);
89 
90 		if (vdev->rx_irq == 0 && vdev->rx_ino != ~0UL)
91 			vdev->rx_irq = sun4v_build_virq(vdev->cdev_handle,
92 							vdev->rx_ino);
93 	}
94 
95 	return drv->probe(vdev, id);
96 }
97 
98 static void vio_device_remove(struct device *dev)
99 {
100 	struct vio_dev *vdev = to_vio_dev(dev);
101 	struct vio_driver *drv = to_vio_driver(dev->driver);
102 
103 	if (drv->remove) {
104 		/*
105 		 * Ideally, we would remove/deallocate tx/rx virqs
106 		 * here - however, there are currently no support
107 		 * routines to do so at the moment. TBD
108 		 */
109 
110 		drv->remove(vdev);
111 	}
112 }
113 
114 static ssize_t devspec_show(struct device *dev,
115 		struct device_attribute *attr, char *buf)
116 {
117 	struct vio_dev *vdev = to_vio_dev(dev);
118 	const char *str = "none";
119 
120 	if (!strcmp(vdev->type, "vnet-port"))
121 		str = "vnet";
122 	else if (!strcmp(vdev->type, "vdc-port"))
123 		str = "vdisk";
124 
125 	return sysfs_emit(buf, "%s\n", str);
126 }
127 static DEVICE_ATTR_RO(devspec);
128 
129 static ssize_t type_show(struct device *dev,
130 		struct device_attribute *attr, char *buf)
131 {
132 	struct vio_dev *vdev = to_vio_dev(dev);
133 	return sysfs_emit(buf, "%s\n", vdev->type);
134 }
135 static DEVICE_ATTR_RO(type);
136 
137 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
138 			     char *buf)
139 {
140 	const struct vio_dev *vdev = to_vio_dev(dev);
141 
142 	return sysfs_emit(buf, "vio:T%sS%s\n", vdev->type, vdev->compat);
143 }
144 static DEVICE_ATTR_RO(modalias);
145 
146 static struct attribute *vio_dev_attrs[] = {
147 	&dev_attr_devspec.attr,
148 	&dev_attr_type.attr,
149 	&dev_attr_modalias.attr,
150 	NULL,
151  };
152 ATTRIBUTE_GROUPS(vio_dev);
153 
154 static const struct bus_type vio_bus_type = {
155 	.name		= "vio",
156 	.dev_groups	= vio_dev_groups,
157 	.uevent         = vio_hotplug,
158 	.match		= vio_bus_match,
159 	.probe		= vio_device_probe,
160 	.remove		= vio_device_remove,
161 };
162 
163 int __vio_register_driver(struct vio_driver *viodrv, struct module *owner,
164 			const char *mod_name)
165 {
166 	viodrv->driver.bus = &vio_bus_type;
167 	viodrv->driver.name = viodrv->name;
168 	viodrv->driver.owner = owner;
169 	viodrv->driver.mod_name = mod_name;
170 
171 	return driver_register(&viodrv->driver);
172 }
173 EXPORT_SYMBOL(__vio_register_driver);
174 
175 void vio_unregister_driver(struct vio_driver *viodrv)
176 {
177 	driver_unregister(&viodrv->driver);
178 }
179 EXPORT_SYMBOL(vio_unregister_driver);
180 
181 static void vio_dev_release(struct device *dev)
182 {
183 	kfree(to_vio_dev(dev));
184 }
185 
186 static ssize_t
187 show_pciobppath_attr(struct device *dev, struct device_attribute *attr,
188 		     char *buf)
189 {
190 	struct vio_dev *vdev;
191 	struct device_node *dp;
192 
193 	vdev = to_vio_dev(dev);
194 	dp = vdev->dp;
195 
196 	return sysfs_emit(buf, "%pOF\n", dp);
197 }
198 
199 static DEVICE_ATTR(obppath, S_IRUSR | S_IRGRP | S_IROTH,
200 		   show_pciobppath_attr, NULL);
201 
202 static struct device_node *cdev_node;
203 
204 static struct vio_dev *root_vdev;
205 static u64 cdev_cfg_handle;
206 
207 static const u64 *vio_cfg_handle(struct mdesc_handle *hp, u64 node)
208 {
209 	const u64 *cfg_handle = NULL;
210 	u64 a;
211 
212 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
213 		u64 target;
214 
215 		target = mdesc_arc_target(hp, a);
216 		cfg_handle = mdesc_get_property(hp, target,
217 						"cfg-handle", NULL);
218 		if (cfg_handle)
219 			break;
220 	}
221 
222 	return cfg_handle;
223 }
224 
225 /**
226  * vio_vdev_node() - Find VDEV node in MD
227  * @hp:  Handle to the MD
228  * @vdev:  Pointer to VDEV
229  *
230  * Find the node in the current MD which matches the given vio_dev. This
231  * must be done dynamically since the node value can change if the MD
232  * is updated.
233  *
234  * NOTE: the MD must be locked, using mdesc_grab(), when calling this routine
235  *
236  * Return: The VDEV node in MDESC
237  */
238 u64 vio_vdev_node(struct mdesc_handle *hp, struct vio_dev *vdev)
239 {
240 	u64 node;
241 
242 	if (vdev == NULL)
243 		return MDESC_NODE_NULL;
244 
245 	node = mdesc_get_node(hp, (const char *)vdev->node_name,
246 			      &vdev->md_node_info);
247 
248 	return node;
249 }
250 EXPORT_SYMBOL(vio_vdev_node);
251 
252 static void vio_fill_channel_info(struct mdesc_handle *hp, u64 mp,
253 				  struct vio_dev *vdev)
254 {
255 	u64 a;
256 
257 	vdev->tx_ino = ~0UL;
258 	vdev->rx_ino = ~0UL;
259 	vdev->channel_id = ~0UL;
260 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
261 		const u64 *chan_id;
262 		const u64 *irq;
263 		u64 target;
264 
265 		target = mdesc_arc_target(hp, a);
266 
267 		irq = mdesc_get_property(hp, target, "tx-ino", NULL);
268 		if (irq)
269 			vdev->tx_ino = *irq;
270 
271 		irq = mdesc_get_property(hp, target, "rx-ino", NULL);
272 		if (irq)
273 			vdev->rx_ino = *irq;
274 
275 		chan_id = mdesc_get_property(hp, target, "id", NULL);
276 		if (chan_id)
277 			vdev->channel_id = *chan_id;
278 	}
279 
280 	vdev->cdev_handle = cdev_cfg_handle;
281 }
282 
283 int vio_set_intr(unsigned long dev_ino, int state)
284 {
285 	int err;
286 
287 	err = sun4v_vintr_set_valid(cdev_cfg_handle, dev_ino, state);
288 	return err;
289 }
290 EXPORT_SYMBOL(vio_set_intr);
291 
292 static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
293 				      const char *node_name,
294 				      struct device *parent)
295 {
296 	const char *type, *compat;
297 	struct device_node *dp;
298 	struct vio_dev *vdev;
299 	int err, tlen, clen;
300 	const u64 *id, *cfg_handle;
301 
302 	type = mdesc_get_property(hp, mp, "device-type", &tlen);
303 	if (!type) {
304 		type = mdesc_get_property(hp, mp, "name", &tlen);
305 		if (!type) {
306 			type = mdesc_node_name(hp, mp);
307 			tlen = strlen(type) + 1;
308 		}
309 	}
310 	if (tlen > VIO_MAX_TYPE_LEN || strlen(type) >= VIO_MAX_TYPE_LEN) {
311 		printk(KERN_ERR "VIO: Type string [%s] is too long.\n",
312 		       type);
313 		return NULL;
314 	}
315 
316 	id = mdesc_get_property(hp, mp, "id", NULL);
317 
318 	cfg_handle = vio_cfg_handle(hp, mp);
319 
320 	compat = mdesc_get_property(hp, mp, "device-type", &clen);
321 	if (!compat) {
322 		clen = 0;
323 	} else if (clen > VIO_MAX_COMPAT_LEN) {
324 		printk(KERN_ERR "VIO: Compat len %d for [%s] is too long.\n",
325 		       clen, type);
326 		return NULL;
327 	}
328 
329 	vdev = kzalloc_obj(*vdev);
330 	if (!vdev) {
331 		printk(KERN_ERR "VIO: Could not allocate vio_dev\n");
332 		return NULL;
333 	}
334 
335 	vdev->mp = mp;
336 	memcpy(vdev->type, type, tlen);
337 	if (compat)
338 		memcpy(vdev->compat, compat, clen);
339 	else
340 		memset(vdev->compat, 0, sizeof(vdev->compat));
341 	vdev->compat_len = clen;
342 
343 	vdev->port_id = ~0UL;
344 	vdev->tx_irq = 0;
345 	vdev->rx_irq = 0;
346 
347 	vio_fill_channel_info(hp, mp, vdev);
348 
349 	if (!id) {
350 		dev_set_name(&vdev->dev, "%s", type);
351 		vdev->dev_no = ~(u64)0;
352 	} else if (!cfg_handle) {
353 		dev_set_name(&vdev->dev, "%s-%llu", type, *id);
354 		vdev->dev_no = *id;
355 	} else {
356 		dev_set_name(&vdev->dev, "%s-%llu-%llu", type,
357 			     *cfg_handle, *id);
358 		vdev->dev_no = *cfg_handle;
359 		vdev->port_id = *id;
360 	}
361 
362 	vdev->dev.parent = parent;
363 	vdev->dev.bus = &vio_bus_type;
364 	vdev->dev.release = vio_dev_release;
365 
366 	if (parent == NULL) {
367 		dp = cdev_node;
368 	} else if (to_vio_dev(parent) == root_vdev) {
369 		for_each_child_of_node(cdev_node, dp) {
370 			if (of_node_is_type(dp, type))
371 				break;
372 		}
373 	} else {
374 		dp = to_vio_dev(parent)->dp;
375 	}
376 	vdev->dp = dp;
377 
378 	/*
379 	 * node_name is NULL for the parent/channel-devices node and
380 	 * the parent doesn't require the MD node info.
381 	 */
382 	if (node_name != NULL) {
383 		strscpy(vdev->node_name, node_name);
384 
385 		err = mdesc_get_node_info(hp, mp, node_name,
386 					  &vdev->md_node_info);
387 		if (err) {
388 			pr_err("VIO: Could not get MD node info %s, err=%d\n",
389 			       dev_name(&vdev->dev), err);
390 			kfree(vdev);
391 			return NULL;
392 		}
393 	}
394 
395 	pr_info("VIO: Adding device %s (tx_ino = %llx, rx_ino = %llx)\n",
396 		dev_name(&vdev->dev), vdev->tx_ino, vdev->rx_ino);
397 
398 	err = device_register(&vdev->dev);
399 	if (err) {
400 		printk(KERN_ERR "VIO: Could not register device %s, err=%d\n",
401 		       dev_name(&vdev->dev), err);
402 		put_device(&vdev->dev);
403 		return NULL;
404 	}
405 	if (vdev->dp)
406 		err = sysfs_create_file(&vdev->dev.kobj,
407 					&dev_attr_obppath.attr);
408 
409 	return vdev;
410 }
411 
412 static void vio_add(struct mdesc_handle *hp, u64 node,
413 		    const char *node_name)
414 {
415 	(void) vio_create_one(hp, node, node_name, &root_vdev->dev);
416 }
417 
418 struct vio_remove_node_data {
419 	struct mdesc_handle *hp;
420 	u64 node;
421 };
422 
423 static int vio_md_node_match(struct device *dev, const void *arg)
424 {
425 	struct vio_dev *vdev = to_vio_dev(dev);
426 	const struct vio_remove_node_data *node_data;
427 	u64 node;
428 
429 	node_data = (const struct vio_remove_node_data *)arg;
430 
431 	node = vio_vdev_node(node_data->hp, vdev);
432 
433 	if (node == node_data->node)
434 		return 1;
435 	else
436 		return 0;
437 }
438 
439 static void vio_remove(struct mdesc_handle *hp, u64 node, const char *node_name)
440 {
441 	struct vio_remove_node_data node_data;
442 	struct device *dev;
443 
444 	node_data.hp = hp;
445 	node_data.node = node;
446 
447 	dev = device_find_child(&root_vdev->dev, (void *)&node_data,
448 				vio_md_node_match);
449 	if (dev) {
450 		printk(KERN_INFO "VIO: Removing device %s\n", dev_name(dev));
451 
452 		device_unregister(dev);
453 		put_device(dev);
454 	} else {
455 		pr_err("VIO: %s node not found in MDESC\n", node_name);
456 	}
457 }
458 
459 static struct mdesc_notifier_client vio_device_notifier = {
460 	.add		= vio_add,
461 	.remove		= vio_remove,
462 	.node_name	= "virtual-device-port",
463 };
464 
465 /* We are only interested in domain service ports under the
466  * "domain-services" node.  On control nodes there is another port
467  * under "openboot" that we should not mess with as aparently that is
468  * reserved exclusively for OBP use.
469  */
470 static void vio_add_ds(struct mdesc_handle *hp, u64 node,
471 		       const char *node_name)
472 {
473 	int found;
474 	u64 a;
475 
476 	found = 0;
477 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
478 		u64 target = mdesc_arc_target(hp, a);
479 		const char *name = mdesc_node_name(hp, target);
480 
481 		if (!strcmp(name, "domain-services")) {
482 			found = 1;
483 			break;
484 		}
485 	}
486 
487 	if (found)
488 		(void) vio_create_one(hp, node, node_name, &root_vdev->dev);
489 }
490 
491 static struct mdesc_notifier_client vio_ds_notifier = {
492 	.add		= vio_add_ds,
493 	.remove		= vio_remove,
494 	.node_name	= "domain-services-port",
495 };
496 
497 static const char *channel_devices_node = "channel-devices";
498 static const char *channel_devices_compat = "SUNW,sun4v-channel-devices";
499 static const char *cfg_handle_prop = "cfg-handle";
500 
501 static int __init vio_init(void)
502 {
503 	struct mdesc_handle *hp;
504 	const char *compat;
505 	const u64 *cfg_handle;
506 	int err, len;
507 	u64 root;
508 
509 	err = bus_register(&vio_bus_type);
510 	if (err) {
511 		printk(KERN_ERR "VIO: Could not register bus type err=%d\n",
512 		       err);
513 		return err;
514 	}
515 
516 	hp = mdesc_grab();
517 	if (!hp)
518 		return 0;
519 
520 	root = mdesc_node_by_name(hp, MDESC_NODE_NULL, channel_devices_node);
521 	if (root == MDESC_NODE_NULL) {
522 		printk(KERN_INFO "VIO: No channel-devices MDESC node.\n");
523 		mdesc_release(hp);
524 		return 0;
525 	}
526 
527 	cdev_node = of_find_node_by_name(NULL, "channel-devices");
528 	err = -ENODEV;
529 	if (!cdev_node) {
530 		printk(KERN_INFO "VIO: No channel-devices OBP node.\n");
531 		goto out_release;
532 	}
533 
534 	compat = mdesc_get_property(hp, root, "compatible", &len);
535 	if (!compat) {
536 		printk(KERN_ERR "VIO: Channel devices lacks compatible "
537 		       "property\n");
538 		goto out_release;
539 	}
540 	if (!of_find_in_proplist(compat, channel_devices_compat, len)) {
541 		printk(KERN_ERR "VIO: Channel devices node lacks (%s) "
542 		       "compat entry.\n", channel_devices_compat);
543 		goto out_release;
544 	}
545 
546 	cfg_handle = mdesc_get_property(hp, root, cfg_handle_prop, NULL);
547 	if (!cfg_handle) {
548 		printk(KERN_ERR "VIO: Channel devices lacks %s property\n",
549 		       cfg_handle_prop);
550 		goto out_release;
551 	}
552 
553 	cdev_cfg_handle = *cfg_handle;
554 
555 	root_vdev = vio_create_one(hp, root, NULL, NULL);
556 	err = -ENODEV;
557 	if (!root_vdev) {
558 		printk(KERN_ERR "VIO: Could not create root device.\n");
559 		goto out_release;
560 	}
561 
562 	mdesc_register_notifier(&vio_device_notifier);
563 	mdesc_register_notifier(&vio_ds_notifier);
564 
565 	mdesc_release(hp);
566 
567 	return err;
568 
569 out_release:
570 	mdesc_release(hp);
571 	return err;
572 }
573 
574 postcore_initcall(vio_init);
575