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
21static 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
48static 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
60static 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
76static 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
87static 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
101static 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
108static struct device_attribute vio_dev_attrs[] = {
109	__ATTR_RO(devspec),
110	__ATTR_RO(type),
111	__ATTR_NULL
112};
113
114static 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
122int __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}
132EXPORT_SYMBOL(__vio_register_driver);
133
134void vio_unregister_driver(struct vio_driver *viodrv)
135{
136	driver_unregister(&viodrv->driver);
137}
138EXPORT_SYMBOL(vio_unregister_driver);
139
140static void vio_dev_release(struct device *dev)
141{
142	kfree(to_vio_dev(dev));
143}
144
145static ssize_t
146show_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
158static DEVICE_ATTR(obppath, S_IRUSR | S_IRGRP | S_IROTH,
159		   show_pciobppath_attr, NULL);
160
161static struct device_node *cdev_node;
162
163static struct vio_dev *root_vdev;
164static u64 cdev_cfg_handle;
165
166static 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			vdev->rx_ino = *irq;
186		}
187
188		chan_id = mdesc_get_property(hp, target, "id", NULL);
189		if (chan_id)
190			vdev->channel_id = *chan_id;
191	}
192}
193
194int vio_set_intr(unsigned long dev_ino, int state)
195{
196	int err;
197
198	err = sun4v_vintr_set_valid(cdev_cfg_handle, dev_ino, state);
199	return err;
200}
201EXPORT_SYMBOL(vio_set_intr);
202
203static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
204				      struct device *parent)
205{
206	const char *type, *compat, *bus_id_name;
207	struct device_node *dp;
208	struct vio_dev *vdev;
209	int err, tlen, clen;
210	const u64 *id, *cfg_handle;
211	u64 a;
212
213	type = mdesc_get_property(hp, mp, "device-type", &tlen);
214	if (!type) {
215		type = mdesc_get_property(hp, mp, "name", &tlen);
216		if (!type) {
217			type = mdesc_node_name(hp, mp);
218			tlen = strlen(type) + 1;
219		}
220	}
221	if (tlen > VIO_MAX_TYPE_LEN) {
222		printk(KERN_ERR "VIO: Type string [%s] is too long.\n",
223		       type);
224		return NULL;
225	}
226
227	id = mdesc_get_property(hp, mp, "id", NULL);
228
229	cfg_handle = NULL;
230	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
231		u64 target;
232
233		target = mdesc_arc_target(hp, a);
234		cfg_handle = mdesc_get_property(hp, target,
235						"cfg-handle", NULL);
236		if (cfg_handle)
237			break;
238	}
239
240	bus_id_name = type;
241	if (!strcmp(type, "domain-services-port"))
242		bus_id_name = "ds";
243
244	/*
245	 * 20 char is the old driver-core name size limit, which is no more.
246	 * This check can probably be removed after review and possible
247	 * adaption of the vio users name length handling.
248	 */
249	if (strlen(bus_id_name) >= 20 - 4) {
250		printk(KERN_ERR "VIO: bus_id_name [%s] is too long.\n",
251		       bus_id_name);
252		return NULL;
253	}
254
255	compat = mdesc_get_property(hp, mp, "device-type", &clen);
256	if (!compat) {
257		clen = 0;
258	} else if (clen > VIO_MAX_COMPAT_LEN) {
259		printk(KERN_ERR "VIO: Compat len %d for [%s] is too long.\n",
260		       clen, type);
261		return NULL;
262	}
263
264	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
265	if (!vdev) {
266		printk(KERN_ERR "VIO: Could not allocate vio_dev\n");
267		return NULL;
268	}
269
270	vdev->mp = mp;
271	memcpy(vdev->type, type, tlen);
272	if (compat)
273		memcpy(vdev->compat, compat, clen);
274	else
275		memset(vdev->compat, 0, sizeof(vdev->compat));
276	vdev->compat_len = clen;
277
278	vdev->channel_id = ~0UL;
279	vdev->tx_irq = ~0;
280	vdev->rx_irq = ~0;
281
282	vio_fill_channel_info(hp, mp, vdev);
283
284	if (!id) {
285		dev_set_name(&vdev->dev, "%s", bus_id_name);
286		vdev->dev_no = ~(u64)0;
287	} else if (!cfg_handle) {
288		dev_set_name(&vdev->dev, "%s-%llu", bus_id_name, *id);
289		vdev->dev_no = *id;
290	} else {
291		dev_set_name(&vdev->dev, "%s-%llu-%llu", bus_id_name,
292			     *cfg_handle, *id);
293		vdev->dev_no = *cfg_handle;
294	}
295
296	vdev->dev.parent = parent;
297	vdev->dev.bus = &vio_bus_type;
298	vdev->dev.release = vio_dev_release;
299
300	if (parent == NULL) {
301		dp = cdev_node;
302	} else if (to_vio_dev(parent) == root_vdev) {
303		dp = of_get_next_child(cdev_node, NULL);
304		while (dp) {
305			if (!strcmp(dp->type, type))
306				break;
307
308			dp = of_get_next_child(cdev_node, dp);
309		}
310	} else {
311		dp = to_vio_dev(parent)->dp;
312	}
313	vdev->dp = dp;
314
315	printk(KERN_INFO "VIO: Adding device %s\n", dev_name(&vdev->dev));
316
317	err = device_register(&vdev->dev);
318	if (err) {
319		printk(KERN_ERR "VIO: Could not register device %s, err=%d\n",
320		       dev_name(&vdev->dev), err);
321		kfree(vdev);
322		return NULL;
323	}
324	if (vdev->dp)
325		err = sysfs_create_file(&vdev->dev.kobj,
326					&dev_attr_obppath.attr);
327
328	return vdev;
329}
330
331static void vio_add(struct mdesc_handle *hp, u64 node)
332{
333	(void) vio_create_one(hp, node, &root_vdev->dev);
334}
335
336static int vio_md_node_match(struct device *dev, void *arg)
337{
338	struct vio_dev *vdev = to_vio_dev(dev);
339
340	if (vdev->mp == (u64) arg)
341		return 1;
342
343	return 0;
344}
345
346static void vio_remove(struct mdesc_handle *hp, u64 node)
347{
348	struct device *dev;
349
350	dev = device_find_child(&root_vdev->dev, (void *) node,
351				vio_md_node_match);
352	if (dev) {
353		printk(KERN_INFO "VIO: Removing device %s\n", dev_name(dev));
354
355		device_unregister(dev);
356		put_device(dev);
357	}
358}
359
360static struct mdesc_notifier_client vio_device_notifier = {
361	.add		= vio_add,
362	.remove		= vio_remove,
363	.node_name	= "virtual-device-port",
364};
365
366/* We are only interested in domain service ports under the
367 * "domain-services" node.  On control nodes there is another port
368 * under "openboot" that we should not mess with as aparently that is
369 * reserved exclusively for OBP use.
370 */
371static void vio_add_ds(struct mdesc_handle *hp, u64 node)
372{
373	int found;
374	u64 a;
375
376	found = 0;
377	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
378		u64 target = mdesc_arc_target(hp, a);
379		const char *name = mdesc_node_name(hp, target);
380
381		if (!strcmp(name, "domain-services")) {
382			found = 1;
383			break;
384		}
385	}
386
387	if (found)
388		(void) vio_create_one(hp, node, &root_vdev->dev);
389}
390
391static struct mdesc_notifier_client vio_ds_notifier = {
392	.add		= vio_add_ds,
393	.remove		= vio_remove,
394	.node_name	= "domain-services-port",
395};
396
397static const char *channel_devices_node = "channel-devices";
398static const char *channel_devices_compat = "SUNW,sun4v-channel-devices";
399static const char *cfg_handle_prop = "cfg-handle";
400
401static int __init vio_init(void)
402{
403	struct mdesc_handle *hp;
404	const char *compat;
405	const u64 *cfg_handle;
406	int err, len;
407	u64 root;
408
409	err = bus_register(&vio_bus_type);
410	if (err) {
411		printk(KERN_ERR "VIO: Could not register bus type err=%d\n",
412		       err);
413		return err;
414	}
415
416	hp = mdesc_grab();
417	if (!hp)
418		return 0;
419
420	root = mdesc_node_by_name(hp, MDESC_NODE_NULL, channel_devices_node);
421	if (root == MDESC_NODE_NULL) {
422		printk(KERN_INFO "VIO: No channel-devices MDESC node.\n");
423		mdesc_release(hp);
424		return 0;
425	}
426
427	cdev_node = of_find_node_by_name(NULL, "channel-devices");
428	err = -ENODEV;
429	if (!cdev_node) {
430		printk(KERN_INFO "VIO: No channel-devices OBP node.\n");
431		goto out_release;
432	}
433
434	compat = mdesc_get_property(hp, root, "compatible", &len);
435	if (!compat) {
436		printk(KERN_ERR "VIO: Channel devices lacks compatible "
437		       "property\n");
438		goto out_release;
439	}
440	if (!of_find_in_proplist(compat, channel_devices_compat, len)) {
441		printk(KERN_ERR "VIO: Channel devices node lacks (%s) "
442		       "compat entry.\n", channel_devices_compat);
443		goto out_release;
444	}
445
446	cfg_handle = mdesc_get_property(hp, root, cfg_handle_prop, NULL);
447	if (!cfg_handle) {
448		printk(KERN_ERR "VIO: Channel devices lacks %s property\n",
449		       cfg_handle_prop);
450		goto out_release;
451	}
452
453	cdev_cfg_handle = *cfg_handle;
454
455	root_vdev = vio_create_one(hp, root, NULL);
456	err = -ENODEV;
457	if (!root_vdev) {
458		printk(KERN_ERR "VIO: Could not create root device.\n");
459		goto out_release;
460	}
461
462	mdesc_register_notifier(&vio_device_notifier);
463	mdesc_register_notifier(&vio_ds_notifier);
464
465	mdesc_release(hp);
466
467	return err;
468
469out_release:
470	mdesc_release(hp);
471	return err;
472}
473
474postcore_initcall(vio_init);
475