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
186		chan_id = mdesc_get_property(hp, target, "id", NULL);
187		if (chan_id)
188			vdev->channel_id = *chan_id;
189	}
190}
191
192static 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
320static void vio_add(struct mdesc_handle *hp, u64 node)
321{
322	(void) vio_create_one(hp, node, &root_vdev->dev);
323}
324
325static 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
335static 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	}
346}
347
348static struct mdesc_notifier_client vio_device_notifier = {
349	.add		= vio_add,
350	.remove		= vio_remove,
351	.node_name	= "virtual-device-port",
352};
353
354/* We are only interested in domain service ports under the
355 * "domain-services" node.  On control nodes there is another port
356 * under "openboot" that we should not mess with as aparently that is
357 * reserved exclusively for OBP use.
358 */
359static void vio_add_ds(struct mdesc_handle *hp, u64 node)
360{
361	int found;
362	u64 a;
363
364	found = 0;
365	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
366		u64 target = mdesc_arc_target(hp, a);
367		const char *name = mdesc_node_name(hp, target);
368
369		if (!strcmp(name, "domain-services")) {
370			found = 1;
371			break;
372		}
373	}
374
375	if (found)
376		(void) vio_create_one(hp, node, &root_vdev->dev);
377}
378
379static struct mdesc_notifier_client vio_ds_notifier = {
380	.add		= vio_add_ds,
381	.remove		= vio_remove,
382	.node_name	= "domain-services-port",
383};
384
385static const char *channel_devices_node = "channel-devices";
386static const char *channel_devices_compat = "SUNW,sun4v-channel-devices";
387static const char *cfg_handle_prop = "cfg-handle";
388
389static int __init vio_init(void)
390{
391	struct mdesc_handle *hp;
392	const char *compat;
393	const u64 *cfg_handle;
394	int err, len;
395	u64 root;
396
397	err = bus_register(&vio_bus_type);
398	if (err) {
399		printk(KERN_ERR "VIO: Could not register bus type err=%d\n",
400		       err);
401		return err;
402	}
403
404	hp = mdesc_grab();
405	if (!hp)
406		return 0;
407
408	root = mdesc_node_by_name(hp, MDESC_NODE_NULL, channel_devices_node);
409	if (root == MDESC_NODE_NULL) {
410		printk(KERN_INFO "VIO: No channel-devices MDESC node.\n");
411		mdesc_release(hp);
412		return 0;
413	}
414
415	cdev_node = of_find_node_by_name(NULL, "channel-devices");
416	err = -ENODEV;
417	if (!cdev_node) {
418		printk(KERN_INFO "VIO: No channel-devices OBP node.\n");
419		goto out_release;
420	}
421
422	compat = mdesc_get_property(hp, root, "compatible", &len);
423	if (!compat) {
424		printk(KERN_ERR "VIO: Channel devices lacks compatible "
425		       "property\n");
426		goto out_release;
427	}
428	if (!of_find_in_proplist(compat, channel_devices_compat, len)) {
429		printk(KERN_ERR "VIO: Channel devices node lacks (%s) "
430		       "compat entry.\n", channel_devices_compat);
431		goto out_release;
432	}
433
434	cfg_handle = mdesc_get_property(hp, root, cfg_handle_prop, NULL);
435	if (!cfg_handle) {
436		printk(KERN_ERR "VIO: Channel devices lacks %s property\n",
437		       cfg_handle_prop);
438		goto out_release;
439	}
440
441	cdev_cfg_handle = *cfg_handle;
442
443	root_vdev = vio_create_one(hp, root, NULL);
444	err = -ENODEV;
445	if (!root_vdev) {
446		printk(KERN_ERR "VIO: Could not create root device.\n");
447		goto out_release;
448	}
449
450	mdesc_register_notifier(&vio_device_notifier);
451	mdesc_register_notifier(&vio_ds_notifier);
452
453	mdesc_release(hp);
454
455	return err;
456
457out_release:
458	mdesc_release(hp);
459	return err;
460}
461
462postcore_initcall(vio_init);