summaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel/vio.c
blob: cb22a3557c4e88303535336d8859eb2f0da69a7c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
/*
 * IBM PowerPC Virtual I/O Infrastructure Support.
 *
 *    Copyright (c) 2003-2005 IBM Corp.
 *     Dave Engebretsen engebret@us.ibm.com
 *     Santiago Leon santil@us.ibm.com
 *     Hollis Blanchard <hollisb@us.ibm.com>
 *     Stephen Rothwell
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <linux/types.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <linux/kobject.h>

#include <asm/iommu.h>
#include <asm/dma.h>
#include <asm/vio.h>
#include <asm/prom.h>
#include <asm/firmware.h>
#include <asm/tce.h>
#include <asm/abs_addr.h>
#include <asm/page.h>
#include <asm/hvcall.h>
#include <asm/iseries/vio.h>
#include <asm/iseries/hv_types.h>
#include <asm/iseries/hv_lp_config.h>
#include <asm/iseries/hv_call_xm.h>
#include <asm/iseries/iommu.h>

extern struct kset devices_subsys; /* needed for vio_find_name() */

static struct bus_type vio_bus_type;

static struct vio_dev vio_bus_device  = { /* fake "parent" device */
	.name = vio_bus_device.dev.bus_id,
	.type = "",
	.dev.bus_id = "vio",
	.dev.bus = &vio_bus_type,
};

static struct iommu_table *vio_build_iommu_table(struct vio_dev *dev)
{
	const unsigned char *dma_window;
	struct iommu_table *tbl;
	unsigned long offset, size;

	if (firmware_has_feature(FW_FEATURE_ISERIES))
		return vio_build_iommu_table_iseries(dev);

	dma_window = of_get_property(dev->dev.archdata.of_node,
				  "ibm,my-dma-window", NULL);
	if (!dma_window)
		return NULL;

	tbl = kmalloc(sizeof(*tbl), GFP_KERNEL);

	of_parse_dma_window(dev->dev.archdata.of_node, dma_window,
			    &tbl->it_index, &offset, &size);

	/* TCE table size - measured in tce entries */
	tbl->it_size = size >> IOMMU_PAGE_SHIFT;
	/* offset for VIO should always be 0 */
	tbl->it_offset = offset >> IOMMU_PAGE_SHIFT;
	tbl->it_busno = 0;
	tbl->it_type = TCE_VB;

	return iommu_init_table(tbl, -1);
}

/**
 * vio_match_device: - Tell if a VIO device has a matching
 *			VIO device id structure.
 * @ids:	array of VIO device id structures to search in
 * @dev:	the VIO device structure to match against
 *
 * Used by a driver to check whether a VIO device present in the
 * system is in its list of supported devices. Returns the matching
 * vio_device_id structure or NULL if there is no match.
 */
static const struct vio_device_id *vio_match_device(
		const struct vio_device_id *ids, const struct vio_dev *dev)
{
	while (ids->type[0] != '\0') {
		if ((strncmp(dev->type, ids->type, strlen(ids->type)) == 0) &&
		    of_device_is_compatible(dev->dev.archdata.of_node,
					 ids->compat))
			return ids;
		ids++;
	}
	return NULL;
}

/*
 * Convert from struct device to struct vio_dev and pass to driver.
 * dev->driver has already been set by generic code because vio_bus_match
 * succeeded.
 */
static int vio_bus_probe(struct device *dev)
{
	struct vio_dev *viodev = to_vio_dev(dev);
	struct vio_driver *viodrv = to_vio_driver(dev->driver);
	const struct vio_device_id *id;
	int error = -ENODEV;

	if (!viodrv->probe)
		return error;

	id = vio_match_device(viodrv->id_table, viodev);
	if (id)
		error = viodrv->probe(viodev, id);

	return error;
}

/* convert from struct device to struct vio_dev and pass to driver. */
static int vio_bus_remove(struct device *dev)
{
	struct vio_dev *viodev = to_vio_dev(dev);
	struct vio_driver *viodrv = to_vio_driver(dev->driver);

	if (viodrv->remove)
		return viodrv->remove(viodev);

	/* driver can't remove */
	return 1;
}

/**
 * vio_register_driver: - Register a new vio driver
 * @drv:	The vio_driver structure to be registered.
 */
int vio_register_driver(struct vio_driver *viodrv)
{
	printk(KERN_DEBUG "%s: driver %s registering\n", __FUNCTION__,
		viodrv->driver.name);

	/* fill in 'struct driver' fields */
	viodrv->driver.bus = &vio_bus_type;

	return driver_register(&viodrv->driver);
}
EXPORT_SYMBOL(vio_register_driver);

/**
 * vio_unregister_driver - Remove registration of vio driver.
 * @driver:	The vio_driver struct to be removed form registration
 */
void vio_unregister_driver(struct vio_driver *viodrv)
{
	driver_unregister(&viodrv->driver);
}
EXPORT_SYMBOL(vio_unregister_driver);

/* vio_dev refcount hit 0 */
static void __devinit vio_dev_release(struct device *dev)
{
	/* XXX should free TCE table */
	of_node_put(dev->archdata.of_node);
	kfree(to_vio_dev(dev));
}

/**
 * vio_register_device_node: - Register a new vio device.
 * @of_node:	The OF node for this device.
 *
 * Creates and initializes a vio_dev structure from the data in
 * of_node and adds it to the list of virtual devices.
 * Returns a pointer to the created vio_dev or NULL if node has
 * NULL device_type or compatible fields.
 */
struct vio_dev * __devinit vio_register_device_node(struct device_node *of_node)
{
	struct vio_dev *viodev;
	const unsigned int *unit_address;

	/* we need the 'device_type' property, in order to match with drivers */
	if (of_node->type == NULL) {
		printk(KERN_WARNING "%s: node %s missing 'device_type'\n",
				__FUNCTION__,
				of_node->name ? of_node->name : "<unknown>");
		return NULL;
	}

	unit_address = of_get_property(of_node, "reg", NULL);
	if (unit_address == NULL) {
		printk(KERN_WARNING "%s: node %s missing 'reg'\n",
				__FUNCTION__,
				of_node->name ? of_node->name : "<unknown>");
		return NULL;
	}

	/* allocate a vio_dev for this node */
	viodev = kzalloc(sizeof(struct vio_dev), GFP_KERNEL);
	if (viodev == NULL)
		return NULL;

	viodev->irq = irq_of_parse_and_map(of_node, 0);

	snprintf(viodev->dev.bus_id, BUS_ID_SIZE, "%x", *unit_address);
	viodev->name = of_node->name;
	viodev->type = of_node->type;
	viodev->unit_address = *unit_address;
	if (firmware_has_feature(FW_FEATURE_ISERIES)) {
		unit_address = of_get_property(of_node,
				"linux,unit_address", NULL);
		if (unit_address != NULL)
			viodev->unit_address = *unit_address;
	}
	viodev->dev.archdata.of_node = of_node_get(of_node);
	viodev->dev.archdata.dma_ops = &dma_iommu_ops;
	viodev->dev.archdata.dma_data = vio_build_iommu_table(viodev);
	viodev->dev.archdata.numa_node = of_node_to_nid(of_node);

	/* init generic 'struct device' fields: */
	viodev->dev.parent = &vio_bus_device.dev;
	viodev->dev.bus = &vio_bus_type;
	viodev->dev.release = vio_dev_release;

	/* register with generic device framework */
	if (device_register(&viodev->dev)) {
		printk(KERN_ERR "%s: failed to register device %s\n",
				__FUNCTION__, viodev->dev.bus_id);
		/* XXX free TCE table */
		kfree(viodev);
		return NULL;
	}

	return viodev;
}
EXPORT_SYMBOL(vio_register_device_node);

/**
 * vio_bus_init: - Initialize the virtual IO bus
 */
static int __init vio_bus_init(void)
{
	int err;
	struct device_node *node_vroot;

	err = bus_register(&vio_bus_type);
	if (err) {
		printk(KERN_ERR "failed to register VIO bus\n");
		return err;
	}

	/*
	 * The fake parent of all vio devices, just to give us
	 * a nice directory
	 */
	err = device_register(&vio_bus_device.dev);
	if (err) {
		printk(KERN_WARNING "%s: device_register returned %i\n",
				__FUNCTION__, err);
		return err;
	}

	node_vroot = of_find_node_by_name(NULL, "vdevice");
	if (node_vroot) {
		struct device_node *of_node;

		/*
		 * Create struct vio_devices for each virtual device in
		 * the device tree. Drivers will associate with them later.
		 */
		for (of_node = node_vroot->child; of_node != NULL;
				of_node = of_node->sibling)
			vio_register_device_node(of_node);
		of_node_put(node_vroot);
	}

	return 0;
}
__initcall(vio_bus_init);

static ssize_t name_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
}

static ssize_t devspec_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct device_node *of_node = dev->archdata.of_node;

	return sprintf(buf, "%s\n", of_node ? of_node->full_name : "none");
}

static struct device_attribute vio_dev_attrs[] = {
	__ATTR_RO(name),
	__ATTR_RO(devspec),
	__ATTR_NULL
};

void __devinit vio_unregister_device(struct vio_dev *viodev)
{
	device_unregister(&viodev->dev);
}
EXPORT_SYMBOL(vio_unregister_device);

static int vio_bus_match(struct device *dev, struct device_driver *drv)
{
	const struct vio_dev *vio_dev = to_vio_dev(dev);
	struct vio_driver *vio_drv = to_vio_driver(drv);
	const struct vio_device_id *ids = vio_drv->id_table;

	return (ids != NULL) && (vio_match_device(ids, vio_dev) != NULL);
}

static int vio_hotplug(struct device *dev, char **envp, int num_envp,
			char *buffer, int buffer_size)
{
	const struct vio_dev *vio_dev = to_vio_dev(dev);
	struct device_node *dn;
	const char *cp;
	int length;

	if (!num_envp)
		return -ENOMEM;

	dn = dev->archdata.of_node;
	if (!dn)
		return -ENODEV;
	cp = of_get_property(dn, "compatible", &length);
	if (!cp)
		return -ENODEV;

	envp[0] = buffer;
	length = scnprintf(buffer, buffer_size, "MODALIAS=vio:T%sS%s",
				vio_dev->type, cp);
	if ((buffer_size - length) <= 0)
		return -ENOMEM;
	envp[1] = NULL;
	return 0;
}

static struct bus_type vio_bus_type = {
	.name = "vio",
	.dev_attrs = vio_dev_attrs,
	.uevent = vio_hotplug,
	.match = vio_bus_match,
	.probe = vio_bus_probe,
	.remove = vio_bus_remove,
};

/**
 * vio_get_attribute: - get attribute for virtual device
 * @vdev:	The vio device to get property.
 * @which:	The property/attribute to be extracted.
 * @length:	Pointer to length of returned data size (unused if NULL).
 *
 * Calls prom.c's of_get_property() to return the value of the
 * attribute specified by @which
*/
const void *vio_get_attribute(struct vio_dev *vdev, char *which, int *length)
{
	return of_get_property(vdev->dev.archdata.of_node, which, length);
}
EXPORT_SYMBOL(vio_get_attribute);

#ifdef CONFIG_PPC_PSERIES
/* vio_find_name() - internal because only vio.c knows how we formatted the
 * kobject name
 * XXX once vio_bus_type.devices is actually used as a kset in
 * drivers/base/bus.c, this function should be removed in favor of
 * "device_find(kobj_name, &vio_bus_type)"
 */
static struct vio_dev *vio_find_name(const char *kobj_name)
{
	struct kobject *found;

	found = kset_find_obj(&devices_subsys, kobj_name);
	if (!found)
		return NULL;

	return to_vio_dev(container_of(found, struct device, kobj));
}

/**
 * vio_find_node - find an already-registered vio_dev
 * @vnode: device_node of the virtual device we're looking for
 */
struct vio_dev *vio_find_node(struct device_node *vnode)
{
	const uint32_t *unit_address;
	char kobj_name[BUS_ID_SIZE];

	/* construct the kobject name from the device node */
	unit_address = of_get_property(vnode, "reg", NULL);
	if (!unit_address)
		return NULL;
	snprintf(kobj_name, BUS_ID_SIZE, "%x", *unit_address);

	return vio_find_name(kobj_name);
}
EXPORT_SYMBOL(vio_find_node);

int vio_enable_interrupts(struct vio_dev *dev)
{
	int rc = h_vio_signal(dev->unit_address, VIO_IRQ_ENABLE);
	if (rc != H_SUCCESS)
		printk(KERN_ERR "vio: Error 0x%x enabling interrupts\n", rc);
	return rc;
}
EXPORT_SYMBOL(vio_enable_interrupts);

int vio_disable_interrupts(struct vio_dev *dev)
{
	int rc = h_vio_signal(dev->unit_address, VIO_IRQ_DISABLE);
	if (rc != H_SUCCESS)
		printk(KERN_ERR "vio: Error 0x%x disabling interrupts\n", rc);
	return rc;
}
EXPORT_SYMBOL(vio_disable_interrupts);
#endif /* CONFIG_PPC_PSERIES */