xref: /openbmc/linux/arch/sparc/kernel/vio.c (revision 2fa5ebe3)
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/irq.h>
16 #include <linux/export.h>
17 #include <linux/init.h>
18 
19 #include <asm/mdesc.h>
20 #include <asm/vio.h>
21 
22 static const struct vio_device_id *vio_match_device(
23 	const struct vio_device_id *matches,
24 	const struct vio_dev *dev)
25 {
26 	const char *type, *compat;
27 	int len;
28 
29 	type = dev->type;
30 	compat = dev->compat;
31 	len = dev->compat_len;
32 
33 	while (matches->type[0] || matches->compat[0]) {
34 		int match = 1;
35 		if (matches->type[0])
36 			match &= !strcmp(matches->type, type);
37 
38 		if (matches->compat[0]) {
39 			match &= len &&
40 				of_find_in_proplist(compat, matches->compat, len);
41 		}
42 		if (match)
43 			return matches;
44 		matches++;
45 	}
46 	return NULL;
47 }
48 
49 static int vio_hotplug(const struct device *dev, struct kobj_uevent_env *env)
50 {
51 	const struct vio_dev *vio_dev = to_vio_dev(dev);
52 
53 	add_uevent_var(env, "MODALIAS=vio:T%sS%s", vio_dev->type, vio_dev->compat);
54 	return 0;
55 }
56 
57 static int vio_bus_match(struct device *dev, struct device_driver *drv)
58 {
59 	struct vio_dev *vio_dev = to_vio_dev(dev);
60 	struct vio_driver *vio_drv = to_vio_driver(drv);
61 	const struct vio_device_id *matches = vio_drv->id_table;
62 
63 	if (!matches)
64 		return 0;
65 
66 	return vio_match_device(matches, vio_dev) != NULL;
67 }
68 
69 static int vio_device_probe(struct device *dev)
70 {
71 	struct vio_dev *vdev = to_vio_dev(dev);
72 	struct vio_driver *drv = to_vio_driver(dev->driver);
73 	const struct vio_device_id *id;
74 
75 	if (!drv->probe)
76 		return -ENODEV;
77 
78 	id = vio_match_device(drv->id_table, vdev);
79 	if (!id)
80 		return -ENODEV;
81 
82 	/* alloc irqs (unless the driver specified not to) */
83 	if (!drv->no_irq) {
84 		if (vdev->tx_irq == 0 && vdev->tx_ino != ~0UL)
85 			vdev->tx_irq = sun4v_build_virq(vdev->cdev_handle,
86 							vdev->tx_ino);
87 
88 		if (vdev->rx_irq == 0 && vdev->rx_ino != ~0UL)
89 			vdev->rx_irq = sun4v_build_virq(vdev->cdev_handle,
90 							vdev->rx_ino);
91 	}
92 
93 	return drv->probe(vdev, id);
94 }
95 
96 static void vio_device_remove(struct device *dev)
97 {
98 	struct vio_dev *vdev = to_vio_dev(dev);
99 	struct vio_driver *drv = to_vio_driver(dev->driver);
100 
101 	if (drv->remove) {
102 		/*
103 		 * Ideally, we would remove/deallocate tx/rx virqs
104 		 * here - however, there are currently no support
105 		 * routines to do so at the moment. TBD
106 		 */
107 
108 		drv->remove(vdev);
109 	}
110 }
111 
112 static ssize_t devspec_show(struct device *dev,
113 		struct device_attribute *attr, char *buf)
114 {
115 	struct vio_dev *vdev = to_vio_dev(dev);
116 	const char *str = "none";
117 
118 	if (!strcmp(vdev->type, "vnet-port"))
119 		str = "vnet";
120 	else if (!strcmp(vdev->type, "vdc-port"))
121 		str = "vdisk";
122 
123 	return sprintf(buf, "%s\n", str);
124 }
125 static DEVICE_ATTR_RO(devspec);
126 
127 static ssize_t type_show(struct device *dev,
128 		struct device_attribute *attr, char *buf)
129 {
130 	struct vio_dev *vdev = to_vio_dev(dev);
131 	return sprintf(buf, "%s\n", vdev->type);
132 }
133 static DEVICE_ATTR_RO(type);
134 
135 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
136 			     char *buf)
137 {
138 	const struct vio_dev *vdev = to_vio_dev(dev);
139 
140 	return sprintf(buf, "vio:T%sS%s\n", vdev->type, vdev->compat);
141 }
142 static DEVICE_ATTR_RO(modalias);
143 
144 static struct attribute *vio_dev_attrs[] = {
145 	&dev_attr_devspec.attr,
146 	&dev_attr_type.attr,
147 	&dev_attr_modalias.attr,
148 	NULL,
149  };
150 ATTRIBUTE_GROUPS(vio_dev);
151 
152 static struct bus_type vio_bus_type = {
153 	.name		= "vio",
154 	.dev_groups	= vio_dev_groups,
155 	.uevent         = vio_hotplug,
156 	.match		= vio_bus_match,
157 	.probe		= vio_device_probe,
158 	.remove		= vio_device_remove,
159 };
160 
161 int __vio_register_driver(struct vio_driver *viodrv, struct module *owner,
162 			const char *mod_name)
163 {
164 	viodrv->driver.bus = &vio_bus_type;
165 	viodrv->driver.name = viodrv->name;
166 	viodrv->driver.owner = owner;
167 	viodrv->driver.mod_name = mod_name;
168 
169 	return driver_register(&viodrv->driver);
170 }
171 EXPORT_SYMBOL(__vio_register_driver);
172 
173 void vio_unregister_driver(struct vio_driver *viodrv)
174 {
175 	driver_unregister(&viodrv->driver);
176 }
177 EXPORT_SYMBOL(vio_unregister_driver);
178 
179 static void vio_dev_release(struct device *dev)
180 {
181 	kfree(to_vio_dev(dev));
182 }
183 
184 static ssize_t
185 show_pciobppath_attr(struct device *dev, struct device_attribute *attr,
186 		     char *buf)
187 {
188 	struct vio_dev *vdev;
189 	struct device_node *dp;
190 
191 	vdev = to_vio_dev(dev);
192 	dp = vdev->dp;
193 
194 	return scnprintf(buf, PAGE_SIZE, "%pOF\n", dp);
195 }
196 
197 static DEVICE_ATTR(obppath, S_IRUSR | S_IRGRP | S_IROTH,
198 		   show_pciobppath_attr, NULL);
199 
200 static struct device_node *cdev_node;
201 
202 static struct vio_dev *root_vdev;
203 static u64 cdev_cfg_handle;
204 
205 static const u64 *vio_cfg_handle(struct mdesc_handle *hp, u64 node)
206 {
207 	const u64 *cfg_handle = NULL;
208 	u64 a;
209 
210 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
211 		u64 target;
212 
213 		target = mdesc_arc_target(hp, a);
214 		cfg_handle = mdesc_get_property(hp, target,
215 						"cfg-handle", NULL);
216 		if (cfg_handle)
217 			break;
218 	}
219 
220 	return cfg_handle;
221 }
222 
223 /**
224  * vio_vdev_node() - Find VDEV node in MD
225  * @hp:  Handle to the MD
226  * @vdev:  Pointer to VDEV
227  *
228  * Find the node in the current MD which matches the given vio_dev. This
229  * must be done dynamically since the node value can change if the MD
230  * is updated.
231  *
232  * NOTE: the MD must be locked, using mdesc_grab(), when calling this routine
233  *
234  * Return: The VDEV node in MDESC
235  */
236 u64 vio_vdev_node(struct mdesc_handle *hp, struct vio_dev *vdev)
237 {
238 	u64 node;
239 
240 	if (vdev == NULL)
241 		return MDESC_NODE_NULL;
242 
243 	node = mdesc_get_node(hp, (const char *)vdev->node_name,
244 			      &vdev->md_node_info);
245 
246 	return node;
247 }
248 EXPORT_SYMBOL(vio_vdev_node);
249 
250 static void vio_fill_channel_info(struct mdesc_handle *hp, u64 mp,
251 				  struct vio_dev *vdev)
252 {
253 	u64 a;
254 
255 	vdev->tx_ino = ~0UL;
256 	vdev->rx_ino = ~0UL;
257 	vdev->channel_id = ~0UL;
258 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
259 		const u64 *chan_id;
260 		const u64 *irq;
261 		u64 target;
262 
263 		target = mdesc_arc_target(hp, a);
264 
265 		irq = mdesc_get_property(hp, target, "tx-ino", NULL);
266 		if (irq)
267 			vdev->tx_ino = *irq;
268 
269 		irq = mdesc_get_property(hp, target, "rx-ino", NULL);
270 		if (irq)
271 			vdev->rx_ino = *irq;
272 
273 		chan_id = mdesc_get_property(hp, target, "id", NULL);
274 		if (chan_id)
275 			vdev->channel_id = *chan_id;
276 	}
277 
278 	vdev->cdev_handle = cdev_cfg_handle;
279 }
280 
281 int vio_set_intr(unsigned long dev_ino, int state)
282 {
283 	int err;
284 
285 	err = sun4v_vintr_set_valid(cdev_cfg_handle, dev_ino, state);
286 	return err;
287 }
288 EXPORT_SYMBOL(vio_set_intr);
289 
290 static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
291 				      const char *node_name,
292 				      struct device *parent)
293 {
294 	const char *type, *compat;
295 	struct device_node *dp;
296 	struct vio_dev *vdev;
297 	int err, tlen, clen;
298 	const u64 *id, *cfg_handle;
299 
300 	type = mdesc_get_property(hp, mp, "device-type", &tlen);
301 	if (!type) {
302 		type = mdesc_get_property(hp, mp, "name", &tlen);
303 		if (!type) {
304 			type = mdesc_node_name(hp, mp);
305 			tlen = strlen(type) + 1;
306 		}
307 	}
308 	if (tlen > VIO_MAX_TYPE_LEN || strlen(type) >= VIO_MAX_TYPE_LEN) {
309 		printk(KERN_ERR "VIO: Type string [%s] is too long.\n",
310 		       type);
311 		return NULL;
312 	}
313 
314 	id = mdesc_get_property(hp, mp, "id", NULL);
315 
316 	cfg_handle = vio_cfg_handle(hp, mp);
317 
318 	compat = mdesc_get_property(hp, mp, "device-type", &clen);
319 	if (!compat) {
320 		clen = 0;
321 	} else if (clen > VIO_MAX_COMPAT_LEN) {
322 		printk(KERN_ERR "VIO: Compat len %d for [%s] is too long.\n",
323 		       clen, type);
324 		return NULL;
325 	}
326 
327 	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
328 	if (!vdev) {
329 		printk(KERN_ERR "VIO: Could not allocate vio_dev\n");
330 		return NULL;
331 	}
332 
333 	vdev->mp = mp;
334 	memcpy(vdev->type, type, tlen);
335 	if (compat)
336 		memcpy(vdev->compat, compat, clen);
337 	else
338 		memset(vdev->compat, 0, sizeof(vdev->compat));
339 	vdev->compat_len = clen;
340 
341 	vdev->port_id = ~0UL;
342 	vdev->tx_irq = 0;
343 	vdev->rx_irq = 0;
344 
345 	vio_fill_channel_info(hp, mp, vdev);
346 
347 	if (!id) {
348 		dev_set_name(&vdev->dev, "%s", type);
349 		vdev->dev_no = ~(u64)0;
350 	} else if (!cfg_handle) {
351 		dev_set_name(&vdev->dev, "%s-%llu", type, *id);
352 		vdev->dev_no = *id;
353 	} else {
354 		dev_set_name(&vdev->dev, "%s-%llu-%llu", type,
355 			     *cfg_handle, *id);
356 		vdev->dev_no = *cfg_handle;
357 		vdev->port_id = *id;
358 	}
359 
360 	vdev->dev.parent = parent;
361 	vdev->dev.bus = &vio_bus_type;
362 	vdev->dev.release = vio_dev_release;
363 
364 	if (parent == NULL) {
365 		dp = cdev_node;
366 	} else if (to_vio_dev(parent) == root_vdev) {
367 		for_each_child_of_node(cdev_node, dp) {
368 			if (of_node_is_type(dp, type))
369 				break;
370 		}
371 	} else {
372 		dp = to_vio_dev(parent)->dp;
373 	}
374 	vdev->dp = dp;
375 
376 	/*
377 	 * node_name is NULL for the parent/channel-devices node and
378 	 * the parent doesn't require the MD node info.
379 	 */
380 	if (node_name != NULL) {
381 		(void) snprintf(vdev->node_name, VIO_MAX_NAME_LEN, "%s",
382 				node_name);
383 
384 		err = mdesc_get_node_info(hp, mp, node_name,
385 					  &vdev->md_node_info);
386 		if (err) {
387 			pr_err("VIO: Could not get MD node info %s, err=%d\n",
388 			       dev_name(&vdev->dev), err);
389 			kfree(vdev);
390 			return NULL;
391 		}
392 	}
393 
394 	pr_info("VIO: Adding device %s (tx_ino = %llx, rx_ino = %llx)\n",
395 		dev_name(&vdev->dev), vdev->tx_ino, vdev->rx_ino);
396 
397 	err = device_register(&vdev->dev);
398 	if (err) {
399 		printk(KERN_ERR "VIO: Could not register device %s, err=%d\n",
400 		       dev_name(&vdev->dev), err);
401 		put_device(&vdev->dev);
402 		return NULL;
403 	}
404 	if (vdev->dp)
405 		err = sysfs_create_file(&vdev->dev.kobj,
406 					&dev_attr_obppath.attr);
407 
408 	return vdev;
409 }
410 
411 static void vio_add(struct mdesc_handle *hp, u64 node,
412 		    const char *node_name)
413 {
414 	(void) vio_create_one(hp, node, node_name, &root_vdev->dev);
415 }
416 
417 struct vio_remove_node_data {
418 	struct mdesc_handle *hp;
419 	u64 node;
420 };
421 
422 static int vio_md_node_match(struct device *dev, void *arg)
423 {
424 	struct vio_dev *vdev = to_vio_dev(dev);
425 	struct vio_remove_node_data *node_data;
426 	u64 node;
427 
428 	node_data = (struct vio_remove_node_data *)arg;
429 
430 	node = vio_vdev_node(node_data->hp, vdev);
431 
432 	if (node == node_data->node)
433 		return 1;
434 	else
435 		return 0;
436 }
437 
438 static void vio_remove(struct mdesc_handle *hp, u64 node, const char *node_name)
439 {
440 	struct vio_remove_node_data node_data;
441 	struct device *dev;
442 
443 	node_data.hp = hp;
444 	node_data.node = node;
445 
446 	dev = device_find_child(&root_vdev->dev, (void *)&node_data,
447 				vio_md_node_match);
448 	if (dev) {
449 		printk(KERN_INFO "VIO: Removing device %s\n", dev_name(dev));
450 
451 		device_unregister(dev);
452 		put_device(dev);
453 	} else {
454 		pr_err("VIO: %s node not found in MDESC\n", node_name);
455 	}
456 }
457 
458 static struct mdesc_notifier_client vio_device_notifier = {
459 	.add		= vio_add,
460 	.remove		= vio_remove,
461 	.node_name	= "virtual-device-port",
462 };
463 
464 /* We are only interested in domain service ports under the
465  * "domain-services" node.  On control nodes there is another port
466  * under "openboot" that we should not mess with as aparently that is
467  * reserved exclusively for OBP use.
468  */
469 static void vio_add_ds(struct mdesc_handle *hp, u64 node,
470 		       const char *node_name)
471 {
472 	int found;
473 	u64 a;
474 
475 	found = 0;
476 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
477 		u64 target = mdesc_arc_target(hp, a);
478 		const char *name = mdesc_node_name(hp, target);
479 
480 		if (!strcmp(name, "domain-services")) {
481 			found = 1;
482 			break;
483 		}
484 	}
485 
486 	if (found)
487 		(void) vio_create_one(hp, node, node_name, &root_vdev->dev);
488 }
489 
490 static struct mdesc_notifier_client vio_ds_notifier = {
491 	.add		= vio_add_ds,
492 	.remove		= vio_remove,
493 	.node_name	= "domain-services-port",
494 };
495 
496 static const char *channel_devices_node = "channel-devices";
497 static const char *channel_devices_compat = "SUNW,sun4v-channel-devices";
498 static const char *cfg_handle_prop = "cfg-handle";
499 
500 static int __init vio_init(void)
501 {
502 	struct mdesc_handle *hp;
503 	const char *compat;
504 	const u64 *cfg_handle;
505 	int err, len;
506 	u64 root;
507 
508 	err = bus_register(&vio_bus_type);
509 	if (err) {
510 		printk(KERN_ERR "VIO: Could not register bus type err=%d\n",
511 		       err);
512 		return err;
513 	}
514 
515 	hp = mdesc_grab();
516 	if (!hp)
517 		return 0;
518 
519 	root = mdesc_node_by_name(hp, MDESC_NODE_NULL, channel_devices_node);
520 	if (root == MDESC_NODE_NULL) {
521 		printk(KERN_INFO "VIO: No channel-devices MDESC node.\n");
522 		mdesc_release(hp);
523 		return 0;
524 	}
525 
526 	cdev_node = of_find_node_by_name(NULL, "channel-devices");
527 	err = -ENODEV;
528 	if (!cdev_node) {
529 		printk(KERN_INFO "VIO: No channel-devices OBP node.\n");
530 		goto out_release;
531 	}
532 
533 	compat = mdesc_get_property(hp, root, "compatible", &len);
534 	if (!compat) {
535 		printk(KERN_ERR "VIO: Channel devices lacks compatible "
536 		       "property\n");
537 		goto out_release;
538 	}
539 	if (!of_find_in_proplist(compat, channel_devices_compat, len)) {
540 		printk(KERN_ERR "VIO: Channel devices node lacks (%s) "
541 		       "compat entry.\n", channel_devices_compat);
542 		goto out_release;
543 	}
544 
545 	cfg_handle = mdesc_get_property(hp, root, cfg_handle_prop, NULL);
546 	if (!cfg_handle) {
547 		printk(KERN_ERR "VIO: Channel devices lacks %s property\n",
548 		       cfg_handle_prop);
549 		goto out_release;
550 	}
551 
552 	cdev_cfg_handle = *cfg_handle;
553 
554 	root_vdev = vio_create_one(hp, root, NULL, NULL);
555 	err = -ENODEV;
556 	if (!root_vdev) {
557 		printk(KERN_ERR "VIO: Could not create root device.\n");
558 		goto out_release;
559 	}
560 
561 	mdesc_register_notifier(&vio_device_notifier);
562 	mdesc_register_notifier(&vio_ds_notifier);
563 
564 	mdesc_release(hp);
565 
566 	return err;
567 
568 out_release:
569 	mdesc_release(hp);
570 	return err;
571 }
572 
573 postcore_initcall(vio_init);
574