xref: /openbmc/linux/arch/powerpc/platforms/pseries/ibmebus.c (revision a6ca5ac746d104019e76c29e69c2a1fc6dd2b29f)
1 /*
2  * IBM PowerPC IBM eBus Infrastructure Support.
3  *
4  * Copyright (c) 2005 IBM Corporation
5  *  Joachim Fenkes <fenkes@de.ibm.com>
6  *  Heiko J Schick <schickhj@de.ibm.com>
7  *
8  * All rights reserved.
9  *
10  * This source code is distributed under a dual license of GPL v2.0 and OpenIB
11  * BSD.
12  *
13  * OpenIB BSD License
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions are met:
17  *
18  * Redistributions of source code must retain the above copyright notice, this
19  * list of conditions and the following disclaimer.
20  *
21  * Redistributions in binary form must reproduce the above copyright notice,
22  * this list of conditions and the following disclaimer in the documentation
23  * and/or other materials
24  * provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
33  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
34  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <linux/init.h>
40 #include <linux/export.h>
41 #include <linux/console.h>
42 #include <linux/kobject.h>
43 #include <linux/dma-mapping.h>
44 #include <linux/interrupt.h>
45 #include <linux/of.h>
46 #include <linux/slab.h>
47 #include <linux/stat.h>
48 #include <linux/of_platform.h>
49 #include <asm/ibmebus.h>
50 
51 static struct device ibmebus_bus_device = { /* fake "parent" device */
52 	.init_name = "ibmebus",
53 };
54 
55 struct bus_type ibmebus_bus_type;
56 
57 /* These devices will automatically be added to the bus during init */
58 static const struct of_device_id ibmebus_matches[] __initconst = {
59 	{ .compatible = "IBM,lhca" },
60 	{ .compatible = "IBM,lhea" },
61 	{},
62 };
63 
64 static void *ibmebus_alloc_coherent(struct device *dev,
65 				    size_t size,
66 				    dma_addr_t *dma_handle,
67 				    gfp_t flag,
68 				    unsigned long attrs)
69 {
70 	void *mem;
71 
72 	mem = kmalloc(size, flag);
73 	*dma_handle = (dma_addr_t)mem;
74 
75 	return mem;
76 }
77 
78 static void ibmebus_free_coherent(struct device *dev,
79 				  size_t size, void *vaddr,
80 				  dma_addr_t dma_handle,
81 				  unsigned long attrs)
82 {
83 	kfree(vaddr);
84 }
85 
86 static dma_addr_t ibmebus_map_page(struct device *dev,
87 				   struct page *page,
88 				   unsigned long offset,
89 				   size_t size,
90 				   enum dma_data_direction direction,
91 				   unsigned long attrs)
92 {
93 	return (dma_addr_t)(page_address(page) + offset);
94 }
95 
96 static void ibmebus_unmap_page(struct device *dev,
97 			       dma_addr_t dma_addr,
98 			       size_t size,
99 			       enum dma_data_direction direction,
100 			       unsigned long attrs)
101 {
102 	return;
103 }
104 
105 static int ibmebus_map_sg(struct device *dev,
106 			  struct scatterlist *sgl,
107 			  int nents, enum dma_data_direction direction,
108 			  unsigned long attrs)
109 {
110 	struct scatterlist *sg;
111 	int i;
112 
113 	for_each_sg(sgl, sg, nents, i) {
114 		sg->dma_address = (dma_addr_t) sg_virt(sg);
115 		sg->dma_length = sg->length;
116 	}
117 
118 	return nents;
119 }
120 
121 static void ibmebus_unmap_sg(struct device *dev,
122 			     struct scatterlist *sg,
123 			     int nents, enum dma_data_direction direction,
124 			     unsigned long attrs)
125 {
126 	return;
127 }
128 
129 static int ibmebus_dma_supported(struct device *dev, u64 mask)
130 {
131 	return mask == DMA_BIT_MASK(64);
132 }
133 
134 static u64 ibmebus_dma_get_required_mask(struct device *dev)
135 {
136 	return DMA_BIT_MASK(64);
137 }
138 
139 static const struct dma_map_ops ibmebus_dma_ops = {
140 	.alloc              = ibmebus_alloc_coherent,
141 	.free               = ibmebus_free_coherent,
142 	.map_sg             = ibmebus_map_sg,
143 	.unmap_sg           = ibmebus_unmap_sg,
144 	.dma_supported      = ibmebus_dma_supported,
145 	.get_required_mask  = ibmebus_dma_get_required_mask,
146 	.map_page           = ibmebus_map_page,
147 	.unmap_page         = ibmebus_unmap_page,
148 };
149 
150 static int ibmebus_match_path(struct device *dev, void *data)
151 {
152 	struct device_node *dn = to_platform_device(dev)->dev.of_node;
153 	return (dn->full_name &&
154 		(strcasecmp((char *)data, dn->full_name) == 0));
155 }
156 
157 static int ibmebus_match_node(struct device *dev, void *data)
158 {
159 	return to_platform_device(dev)->dev.of_node == data;
160 }
161 
162 static int ibmebus_create_device(struct device_node *dn)
163 {
164 	struct platform_device *dev;
165 	int ret;
166 
167 	dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
168 	if (!dev)
169 		return -ENOMEM;
170 
171 	dev->dev.bus = &ibmebus_bus_type;
172 	dev->dev.dma_ops = &ibmebus_dma_ops;
173 
174 	ret = of_device_add(dev);
175 	if (ret)
176 		platform_device_put(dev);
177 	return ret;
178 }
179 
180 static int ibmebus_create_devices(const struct of_device_id *matches)
181 {
182 	struct device_node *root, *child;
183 	struct device *dev;
184 	int ret = 0;
185 
186 	root = of_find_node_by_path("/");
187 
188 	for_each_child_of_node(root, child) {
189 		if (!of_match_node(matches, child))
190 			continue;
191 
192 		dev = bus_find_device(&ibmebus_bus_type, NULL, child,
193 				      ibmebus_match_node);
194 		if (dev) {
195 			put_device(dev);
196 			continue;
197 		}
198 
199 		ret = ibmebus_create_device(child);
200 		if (ret) {
201 			printk(KERN_ERR "%s: failed to create device (%i)",
202 			       __func__, ret);
203 			of_node_put(child);
204 			break;
205 		}
206 	}
207 
208 	of_node_put(root);
209 	return ret;
210 }
211 
212 int ibmebus_register_driver(struct platform_driver *drv)
213 {
214 	/* If the driver uses devices that ibmebus doesn't know, add them */
215 	ibmebus_create_devices(drv->driver.of_match_table);
216 
217 	drv->driver.bus = &ibmebus_bus_type;
218 	return driver_register(&drv->driver);
219 }
220 EXPORT_SYMBOL(ibmebus_register_driver);
221 
222 void ibmebus_unregister_driver(struct platform_driver *drv)
223 {
224 	driver_unregister(&drv->driver);
225 }
226 EXPORT_SYMBOL(ibmebus_unregister_driver);
227 
228 int ibmebus_request_irq(u32 ist, irq_handler_t handler,
229 			unsigned long irq_flags, const char *devname,
230 			void *dev_id)
231 {
232 	unsigned int irq = irq_create_mapping(NULL, ist);
233 
234 	if (!irq)
235 		return -EINVAL;
236 
237 	return request_irq(irq, handler, irq_flags, devname, dev_id);
238 }
239 EXPORT_SYMBOL(ibmebus_request_irq);
240 
241 void ibmebus_free_irq(u32 ist, void *dev_id)
242 {
243 	unsigned int irq = irq_find_mapping(NULL, ist);
244 
245 	free_irq(irq, dev_id);
246 	irq_dispose_mapping(irq);
247 }
248 EXPORT_SYMBOL(ibmebus_free_irq);
249 
250 static char *ibmebus_chomp(const char *in, size_t count)
251 {
252 	char *out = kmalloc(count + 1, GFP_KERNEL);
253 
254 	if (!out)
255 		return NULL;
256 
257 	memcpy(out, in, count);
258 	out[count] = '\0';
259 	if (out[count - 1] == '\n')
260 		out[count - 1] = '\0';
261 
262 	return out;
263 }
264 
265 static ssize_t ibmebus_store_probe(struct bus_type *bus,
266 				   const char *buf, size_t count)
267 {
268 	struct device_node *dn = NULL;
269 	struct device *dev;
270 	char *path;
271 	ssize_t rc = 0;
272 
273 	path = ibmebus_chomp(buf, count);
274 	if (!path)
275 		return -ENOMEM;
276 
277 	dev = bus_find_device(&ibmebus_bus_type, NULL, path,
278 			      ibmebus_match_path);
279 	if (dev) {
280 		put_device(dev);
281 		printk(KERN_WARNING "%s: %s has already been probed\n",
282 		       __func__, path);
283 		rc = -EEXIST;
284 		goto out;
285 	}
286 
287 	if ((dn = of_find_node_by_path(path))) {
288 		rc = ibmebus_create_device(dn);
289 		of_node_put(dn);
290 	} else {
291 		printk(KERN_WARNING "%s: no such device node: %s\n",
292 		       __func__, path);
293 		rc = -ENODEV;
294 	}
295 
296 out:
297 	kfree(path);
298 	if (rc)
299 		return rc;
300 	return count;
301 }
302 static BUS_ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe);
303 
304 static ssize_t ibmebus_store_remove(struct bus_type *bus,
305 				    const char *buf, size_t count)
306 {
307 	struct device *dev;
308 	char *path;
309 
310 	path = ibmebus_chomp(buf, count);
311 	if (!path)
312 		return -ENOMEM;
313 
314 	if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
315 				   ibmebus_match_path))) {
316 		of_device_unregister(to_platform_device(dev));
317 		put_device(dev);
318 
319 		kfree(path);
320 		return count;
321 	} else {
322 		printk(KERN_WARNING "%s: %s not on the bus\n",
323 		       __func__, path);
324 
325 		kfree(path);
326 		return -ENODEV;
327 	}
328 }
329 static BUS_ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove);
330 
331 static struct attribute *ibmbus_bus_attrs[] = {
332 	&bus_attr_probe.attr,
333 	&bus_attr_remove.attr,
334 	NULL,
335 };
336 ATTRIBUTE_GROUPS(ibmbus_bus);
337 
338 static int ibmebus_bus_bus_match(struct device *dev, struct device_driver *drv)
339 {
340 	const struct of_device_id *matches = drv->of_match_table;
341 
342 	if (!matches)
343 		return 0;
344 
345 	return of_match_device(matches, dev) != NULL;
346 }
347 
348 static int ibmebus_bus_device_probe(struct device *dev)
349 {
350 	int error = -ENODEV;
351 	struct platform_driver *drv;
352 	struct platform_device *of_dev;
353 
354 	drv = to_platform_driver(dev->driver);
355 	of_dev = to_platform_device(dev);
356 
357 	if (!drv->probe)
358 		return error;
359 
360 	of_dev_get(of_dev);
361 
362 	if (of_driver_match_device(dev, dev->driver))
363 		error = drv->probe(of_dev);
364 	if (error)
365 		of_dev_put(of_dev);
366 
367 	return error;
368 }
369 
370 static int ibmebus_bus_device_remove(struct device *dev)
371 {
372 	struct platform_device *of_dev = to_platform_device(dev);
373 	struct platform_driver *drv = to_platform_driver(dev->driver);
374 
375 	if (dev->driver && drv->remove)
376 		drv->remove(of_dev);
377 	return 0;
378 }
379 
380 static void ibmebus_bus_device_shutdown(struct device *dev)
381 {
382 	struct platform_device *of_dev = to_platform_device(dev);
383 	struct platform_driver *drv = to_platform_driver(dev->driver);
384 
385 	if (dev->driver && drv->shutdown)
386 		drv->shutdown(of_dev);
387 }
388 
389 /*
390  * ibmebus_bus_device_attrs
391  */
392 static ssize_t devspec_show(struct device *dev,
393 				struct device_attribute *attr, char *buf)
394 {
395 	struct platform_device *ofdev;
396 
397 	ofdev = to_platform_device(dev);
398 	return sprintf(buf, "%s\n", ofdev->dev.of_node->full_name);
399 }
400 
401 static ssize_t name_show(struct device *dev,
402 				struct device_attribute *attr, char *buf)
403 {
404 	struct platform_device *ofdev;
405 
406 	ofdev = to_platform_device(dev);
407 	return sprintf(buf, "%s\n", ofdev->dev.of_node->name);
408 }
409 
410 static ssize_t modalias_show(struct device *dev,
411 				struct device_attribute *attr, char *buf)
412 {
413 	return of_device_modalias(dev, buf, PAGE_SIZE);
414 }
415 
416 static struct device_attribute ibmebus_bus_device_attrs[] = {
417 	__ATTR_RO(devspec),
418 	__ATTR_RO(name),
419 	__ATTR_RO(modalias),
420 	__ATTR_NULL
421 };
422 
423 struct bus_type ibmebus_bus_type = {
424 	.name      = "ibmebus",
425 	.uevent    = of_device_uevent_modalias,
426 	.bus_groups = ibmbus_bus_groups,
427 	.match     = ibmebus_bus_bus_match,
428 	.probe     = ibmebus_bus_device_probe,
429 	.remove    = ibmebus_bus_device_remove,
430 	.shutdown  = ibmebus_bus_device_shutdown,
431 	.dev_attrs = ibmebus_bus_device_attrs,
432 };
433 EXPORT_SYMBOL(ibmebus_bus_type);
434 
435 static int __init ibmebus_bus_init(void)
436 {
437 	int err;
438 
439 	printk(KERN_INFO "IBM eBus Device Driver\n");
440 
441 	err = bus_register(&ibmebus_bus_type);
442 	if (err) {
443 		printk(KERN_ERR "%s: failed to register IBM eBus.\n",
444 		       __func__);
445 		return err;
446 	}
447 
448 	err = device_register(&ibmebus_bus_device);
449 	if (err) {
450 		printk(KERN_WARNING "%s: device_register returned %i\n",
451 		       __func__, err);
452 		bus_unregister(&ibmebus_bus_type);
453 
454 		return err;
455 	}
456 
457 	err = ibmebus_create_devices(ibmebus_matches);
458 	if (err) {
459 		device_unregister(&ibmebus_bus_device);
460 		bus_unregister(&ibmebus_bus_type);
461 		return err;
462 	}
463 
464 	return 0;
465 }
466 postcore_initcall(ibmebus_bus_init);
467