summaryrefslogtreecommitdiff
path: root/arch/ppc64/kernel/vio.c
blob: 3b790bafcaad8cad86c0340bf508d2f681396468 (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
/*
 * 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/init.h>
#include <linux/console.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <asm/iommu.h>
#include <asm/dma.h>
#include <asm/vio.h>

static const struct vio_device_id *vio_match_device(
		const struct vio_device_id *, const struct vio_dev *);

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 int (*is_match)(const struct vio_device_id *id,
		const struct vio_dev *dev);
static void (*unregister_device_callback)(struct vio_dev *dev);
static void (*release_device_callback)(struct device *dev);

/* 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->name);

	/* fill in 'struct driver' fields */
	viodrv->driver.name = viodrv->name;
	viodrv->driver.bus = &vio_bus_type;
	viodrv->driver.probe = vio_bus_probe;
	viodrv->driver.remove = vio_bus_remove;

	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_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) {
		if (is_match(ids, dev))
			return ids;
		ids++;
	}
	return NULL;
}

/**
 * vio_bus_init: - Initialize the virtual IO bus
 */
int __init vio_bus_init(int (*match_func)(const struct vio_device_id *id,
			const struct vio_dev *dev),
		void (*unregister_dev)(struct vio_dev *),
		void (*release_dev)(struct device *))
{
	int err;

	is_match = match_func;
	unregister_device_callback = unregister_dev;
	release_device_callback = release_dev;

	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;
	}

	return 0;
}

/* vio_dev refcount hit 0 */
static void __devinit vio_dev_release(struct device *dev)
{
	if (release_device_callback)
		release_device_callback(dev);
	kfree(to_vio_dev(dev));
}

static ssize_t viodev_show_name(struct device *dev, struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
}
DEVICE_ATTR(name, S_IRUSR | S_IRGRP | S_IROTH, viodev_show_name, NULL);

struct vio_dev * __devinit vio_register_device_common(
		struct vio_dev *viodev, char *name, char *type,
		uint32_t unit_address, struct iommu_table *iommu_table)
{
	viodev->name = name;
	viodev->type = type;
	viodev->unit_address = unit_address;
	viodev->iommu_table = iommu_table;
	/* 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);
		return NULL;
	}
	device_create_file(&viodev->dev, &dev_attr_name);

	return viodev;
}

void __devinit vio_unregister_device(struct vio_dev *viodev)
{
	if (unregister_device_callback)
		unregister_device_callback(viodev);
	device_remove_file(&viodev->dev, &dev_attr_name);
	device_unregister(&viodev->dev);
}
EXPORT_SYMBOL(vio_unregister_device);

static dma_addr_t vio_map_single(struct device *dev, void *vaddr,
			  size_t size, enum dma_data_direction direction)
{
	return iommu_map_single(to_vio_dev(dev)->iommu_table, vaddr, size,
			direction);
}

static void vio_unmap_single(struct device *dev, dma_addr_t dma_handle,
		      size_t size, enum dma_data_direction direction)
{
	iommu_unmap_single(to_vio_dev(dev)->iommu_table, dma_handle, size,
			direction);
}

static int vio_map_sg(struct device *dev, struct scatterlist *sglist,
		int nelems, enum dma_data_direction direction)
{
	return iommu_map_sg(dev, to_vio_dev(dev)->iommu_table, sglist,
			nelems, direction);
}

static void vio_unmap_sg(struct device *dev, struct scatterlist *sglist,
		int nelems, enum dma_data_direction direction)
{
	iommu_unmap_sg(to_vio_dev(dev)->iommu_table, sglist, nelems, direction);
}

static void *vio_alloc_coherent(struct device *dev, size_t size,
			   dma_addr_t *dma_handle, unsigned int __nocast flag)
{
	return iommu_alloc_coherent(to_vio_dev(dev)->iommu_table, size,
			dma_handle, flag);
}

static void vio_free_coherent(struct device *dev, size_t size,
			 void *vaddr, dma_addr_t dma_handle)
{
	iommu_free_coherent(to_vio_dev(dev)->iommu_table, size, vaddr,
			dma_handle);
}

static int vio_dma_supported(struct device *dev, u64 mask)
{
	return 1;
}

struct dma_mapping_ops vio_dma_ops = {
	.alloc_coherent = vio_alloc_coherent,
	.free_coherent = vio_free_coherent,
	.map_single = vio_map_single,
	.unmap_single = vio_unmap_single,
	.map_sg = vio_map_sg,
	.unmap_sg = vio_unmap_sg,
	.dma_supported = vio_dma_supported,
};

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;
	const struct vio_device_id *found_id;

	if (!ids)
		return 0;

	found_id = vio_match_device(ids, vio_dev);
	if (found_id)
		return 1;

	return 0;
}

struct bus_type vio_bus_type = {
	.name = "vio",
	.match = vio_bus_match,
};