summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/ibmebus.c
blob: 64299d28f36485d3441e0b59604228e141712cb1 (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
/*
 * IBM PowerPC IBM eBus Infrastructure Support.
 *
 * Copyright (c) 2005 IBM Corporation
 *  Joachim Fenkes <fenkes@de.ibm.com>
 *  Heiko J Schick <schickhj@de.ibm.com>
 *
 * All rights reserved.
 *
 * This source code is distributed under a dual license of GPL v2.0 and OpenIB
 * BSD.
 *
 * OpenIB BSD License
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials
 * provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/init.h>
#include <linux/console.h>
#include <linux/kobject.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <asm/ibmebus.h>
#include <asm/abs_addr.h>

static struct device ibmebus_bus_device = { /* fake "parent" device */
	.bus_id = "ibmebus",
};

struct bus_type ibmebus_bus_type;

/* These devices will automatically be added to the bus during init */
static struct of_device_id __initdata ibmebus_matches[] = {
	{ .compatible = "IBM,lhca" },
	{ .compatible = "IBM,lhea" },
	{},
};

static void *ibmebus_alloc_coherent(struct device *dev,
				    size_t size,
				    dma_addr_t *dma_handle,
				    gfp_t flag)
{
	void *mem;

	mem = kmalloc(size, flag);
	*dma_handle = (dma_addr_t)mem;

	return mem;
}

static void ibmebus_free_coherent(struct device *dev,
				  size_t size, void *vaddr,
				  dma_addr_t dma_handle)
{
	kfree(vaddr);
}

static dma_addr_t ibmebus_map_page(struct device *dev,
				   struct page *page,
				   unsigned long offset,
				   size_t size,
				   enum dma_data_direction direction,
				   struct dma_attrs *attrs)
{
	return (dma_addr_t)(page_address(page) + offset);
}

static void ibmebus_unmap_page(struct device *dev,
			       dma_addr_t dma_addr,
			       size_t size,
			       enum dma_data_direction direction,
			       struct dma_attrs *attrs)
{
	return;
}

static int ibmebus_map_sg(struct device *dev,
			  struct scatterlist *sgl,
			  int nents, enum dma_data_direction direction,
			  struct dma_attrs *attrs)
{
	struct scatterlist *sg;
	int i;

	for_each_sg(sgl, sg, nents, i) {
		sg->dma_address = (dma_addr_t) sg_virt(sg);
		sg->dma_length = sg->length;
	}

	return nents;
}

static void ibmebus_unmap_sg(struct device *dev,
			     struct scatterlist *sg,
			     int nents, enum dma_data_direction direction,
			     struct dma_attrs *attrs)
{
	return;
}

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

static struct dma_mapping_ops ibmebus_dma_ops = {
	.alloc_coherent = ibmebus_alloc_coherent,
	.free_coherent  = ibmebus_free_coherent,
	.map_sg         = ibmebus_map_sg,
	.unmap_sg       = ibmebus_unmap_sg,
	.dma_supported  = ibmebus_dma_supported,
	.map_page       = ibmebus_map_page,
	.unmap_page     = ibmebus_unmap_page,
};

static int ibmebus_match_path(struct device *dev, void *data)
{
	struct device_node *dn = to_of_device(dev)->node;
	return (dn->full_name &&
		(strcasecmp((char *)data, dn->full_name) == 0));
}

static int ibmebus_match_node(struct device *dev, void *data)
{
	return to_of_device(dev)->node == data;
}

static int ibmebus_create_device(struct device_node *dn)
{
	struct of_device *dev;
	int ret;

	dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
	if (!dev)
		return -ENOMEM;

	dev->dev.bus = &ibmebus_bus_type;
	dev->dev.archdata.dma_ops = &ibmebus_dma_ops;

	ret = of_device_register(dev);
	if (ret) {
		of_device_free(dev);
		return ret;
	}

	return 0;
}

static int ibmebus_create_devices(const struct of_device_id *matches)
{
	struct device_node *root, *child;
	int ret = 0;

	root = of_find_node_by_path("/");

	for_each_child_of_node(root, child) {
		if (!of_match_node(matches, child))
			continue;

		if (bus_find_device(&ibmebus_bus_type, NULL, child,
				    ibmebus_match_node))
			continue;

		ret = ibmebus_create_device(child);
		if (ret) {
			printk(KERN_ERR "%s: failed to create device (%i)",
			       __func__, ret);
			of_node_put(child);
			break;
		}
	}

	of_node_put(root);
	return ret;
}

int ibmebus_register_driver(struct of_platform_driver *drv)
{
	/* If the driver uses devices that ibmebus doesn't know, add them */
	ibmebus_create_devices(drv->match_table);

	return of_register_driver(drv, &ibmebus_bus_type);
}
EXPORT_SYMBOL(ibmebus_register_driver);

void ibmebus_unregister_driver(struct of_platform_driver *drv)
{
	of_unregister_driver(drv);
}
EXPORT_SYMBOL(ibmebus_unregister_driver);

int ibmebus_request_irq(u32 ist, irq_handler_t handler,
			unsigned long irq_flags, const char *devname,
			void *dev_id)
{
	unsigned int irq = irq_create_mapping(NULL, ist);

	if (irq == NO_IRQ)
		return -EINVAL;

	return request_irq(irq, handler, irq_flags, devname, dev_id);
}
EXPORT_SYMBOL(ibmebus_request_irq);

void ibmebus_free_irq(u32 ist, void *dev_id)
{
	unsigned int irq = irq_find_mapping(NULL, ist);

	free_irq(irq, dev_id);
}
EXPORT_SYMBOL(ibmebus_free_irq);

static char *ibmebus_chomp(const char *in, size_t count)
{
	char *out = kmalloc(count + 1, GFP_KERNEL);

	if (!out)
		return NULL;

	memcpy(out, in, count);
	out[count] = '\0';
	if (out[count - 1] == '\n')
		out[count - 1] = '\0';

	return out;
}

static ssize_t ibmebus_store_probe(struct bus_type *bus,
				   const char *buf, size_t count)
{
	struct device_node *dn = NULL;
	char *path;
	ssize_t rc = 0;

	path = ibmebus_chomp(buf, count);
	if (!path)
		return -ENOMEM;

	if (bus_find_device(&ibmebus_bus_type, NULL, path,
			    ibmebus_match_path)) {
		printk(KERN_WARNING "%s: %s has already been probed\n",
		       __func__, path);
		rc = -EEXIST;
		goto out;
	}

	if ((dn = of_find_node_by_path(path))) {
		rc = ibmebus_create_device(dn);
		of_node_put(dn);
	} else {
		printk(KERN_WARNING "%s: no such device node: %s\n",
		       __func__, path);
		rc = -ENODEV;
	}

out:
	kfree(path);
	if (rc)
		return rc;
	return count;
}

static ssize_t ibmebus_store_remove(struct bus_type *bus,
				    const char *buf, size_t count)
{
	struct device *dev;
	char *path;

	path = ibmebus_chomp(buf, count);
	if (!path)
		return -ENOMEM;

	if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
				   ibmebus_match_path))) {
		of_device_unregister(to_of_device(dev));

		kfree(path);
		return count;
	} else {
		printk(KERN_WARNING "%s: %s not on the bus\n",
		       __func__, path);

		kfree(path);
		return -ENODEV;
	}
}

static struct bus_attribute ibmebus_bus_attrs[] = {
	__ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe),
	__ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove),
	__ATTR_NULL
};

struct bus_type ibmebus_bus_type = {
	.uevent    = of_device_uevent,
	.bus_attrs = ibmebus_bus_attrs
};
EXPORT_SYMBOL(ibmebus_bus_type);

static int __init ibmebus_bus_init(void)
{
	int err;

	printk(KERN_INFO "IBM eBus Device Driver\n");

	err = of_bus_type_init(&ibmebus_bus_type, "ibmebus");
	if (err) {
		printk(KERN_ERR "%s: failed to register IBM eBus.\n",
		       __func__);
		return err;
	}

	err = device_register(&ibmebus_bus_device);
	if (err) {
		printk(KERN_WARNING "%s: device_register returned %i\n",
		       __func__, err);
		bus_unregister(&ibmebus_bus_type);

		return err;
	}

	err = ibmebus_create_devices(ibmebus_matches);
	if (err) {
		device_unregister(&ibmebus_bus_device);
		bus_unregister(&ibmebus_bus_type);
		return err;
	}

	return 0;
}
postcore_initcall(ibmebus_bus_init);