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/console.h>
41 #include <linux/kobject.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/interrupt.h>
44 #include <linux/of.h>
45 #include <linux/of_platform.h>
46 #include <asm/ibmebus.h>
47 #include <asm/abs_addr.h>
48
49 static struct device ibmebus_bus_device = { /* fake "parent" device */
50 .init_name = "ibmebus",
51 };
52
53 struct bus_type ibmebus_bus_type;
54
55 /* These devices will automatically be added to the bus during init */
56 static struct of_device_id __initdata ibmebus_matches[] = {
57 { .compatible = "IBM,lhca" },
58 { .compatible = "IBM,lhea" },
59 {},
60 };
61
ibmebus_alloc_coherent(struct device * dev,size_t size,dma_addr_t * dma_handle,gfp_t flag)62 static void *ibmebus_alloc_coherent(struct device *dev,
63 size_t size,
64 dma_addr_t *dma_handle,
65 gfp_t flag)
66 {
67 void *mem;
68
69 mem = kmalloc(size, flag);
70 *dma_handle = (dma_addr_t)mem;
71
72 return mem;
73 }
74
ibmebus_free_coherent(struct device * dev,size_t size,void * vaddr,dma_addr_t dma_handle)75 static void ibmebus_free_coherent(struct device *dev,
76 size_t size, void *vaddr,
77 dma_addr_t dma_handle)
78 {
79 kfree(vaddr);
80 }
81
ibmebus_map_page(struct device * dev,struct page * page,unsigned long offset,size_t size,enum dma_data_direction direction,struct dma_attrs * attrs)82 static dma_addr_t ibmebus_map_page(struct device *dev,
83 struct page *page,
84 unsigned long offset,
85 size_t size,
86 enum dma_data_direction direction,
87 struct dma_attrs *attrs)
88 {
89 return (dma_addr_t)(page_address(page) + offset);
90 }
91
ibmebus_unmap_page(struct device * dev,dma_addr_t dma_addr,size_t size,enum dma_data_direction direction,struct dma_attrs * attrs)92 static void ibmebus_unmap_page(struct device *dev,
93 dma_addr_t dma_addr,
94 size_t size,
95 enum dma_data_direction direction,
96 struct dma_attrs *attrs)
97 {
98 return;
99 }
100
ibmebus_map_sg(struct device * dev,struct scatterlist * sgl,int nents,enum dma_data_direction direction,struct dma_attrs * attrs)101 static int ibmebus_map_sg(struct device *dev,
102 struct scatterlist *sgl,
103 int nents, enum dma_data_direction direction,
104 struct dma_attrs *attrs)
105 {
106 struct scatterlist *sg;
107 int i;
108
109 for_each_sg(sgl, sg, nents, i) {
110 sg->dma_address = (dma_addr_t) sg_virt(sg);
111 sg->dma_length = sg->length;
112 }
113
114 return nents;
115 }
116
ibmebus_unmap_sg(struct device * dev,struct scatterlist * sg,int nents,enum dma_data_direction direction,struct dma_attrs * attrs)117 static void ibmebus_unmap_sg(struct device *dev,
118 struct scatterlist *sg,
119 int nents, enum dma_data_direction direction,
120 struct dma_attrs *attrs)
121 {
122 return;
123 }
124
ibmebus_dma_supported(struct device * dev,u64 mask)125 static int ibmebus_dma_supported(struct device *dev, u64 mask)
126 {
127 return 1;
128 }
129
130 static struct dma_mapping_ops ibmebus_dma_ops = {
131 .alloc_coherent = ibmebus_alloc_coherent,
132 .free_coherent = ibmebus_free_coherent,
133 .map_sg = ibmebus_map_sg,
134 .unmap_sg = ibmebus_unmap_sg,
135 .dma_supported = ibmebus_dma_supported,
136 .map_page = ibmebus_map_page,
137 .unmap_page = ibmebus_unmap_page,
138 };
139
ibmebus_match_path(struct device * dev,void * data)140 static int ibmebus_match_path(struct device *dev, void *data)
141 {
142 struct device_node *dn = to_of_device(dev)->node;
143 return (dn->full_name &&
144 (strcasecmp((char *)data, dn->full_name) == 0));
145 }
146
ibmebus_match_node(struct device * dev,void * data)147 static int ibmebus_match_node(struct device *dev, void *data)
148 {
149 return to_of_device(dev)->node == data;
150 }
151
ibmebus_create_device(struct device_node * dn)152 static int ibmebus_create_device(struct device_node *dn)
153 {
154 struct of_device *dev;
155 int ret;
156
157 dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
158 if (!dev)
159 return -ENOMEM;
160
161 dev->dev.bus = &ibmebus_bus_type;
162 dev->dev.archdata.dma_ops = &ibmebus_dma_ops;
163
164 ret = of_device_register(dev);
165 if (ret) {
166 of_device_free(dev);
167 return ret;
168 }
169
170 return 0;
171 }
172
ibmebus_create_devices(const struct of_device_id * matches)173 static int ibmebus_create_devices(const struct of_device_id *matches)
174 {
175 struct device_node *root, *child;
176 int ret = 0;
177
178 root = of_find_node_by_path("/");
179
180 for_each_child_of_node(root, child) {
181 if (!of_match_node(matches, child))
182 continue;
183
184 if (bus_find_device(&ibmebus_bus_type, NULL, child,
185 ibmebus_match_node))
186 continue;
187
188 ret = ibmebus_create_device(child);
189 if (ret) {
190 printk(KERN_ERR "%s: failed to create device (%i)",
191 __func__, ret);
192 of_node_put(child);
193 break;
194 }
195 }
196
197 of_node_put(root);
198 return ret;
199 }
200
ibmebus_register_driver(struct of_platform_driver * drv)201 int ibmebus_register_driver(struct of_platform_driver *drv)
202 {
203 /* If the driver uses devices that ibmebus doesn't know, add them */
204 ibmebus_create_devices(drv->match_table);
205
206 return of_register_driver(drv, &ibmebus_bus_type);
207 }
208 EXPORT_SYMBOL(ibmebus_register_driver);
209
ibmebus_unregister_driver(struct of_platform_driver * drv)210 void ibmebus_unregister_driver(struct of_platform_driver *drv)
211 {
212 of_unregister_driver(drv);
213 }
214 EXPORT_SYMBOL(ibmebus_unregister_driver);
215
ibmebus_request_irq(u32 ist,irq_handler_t handler,unsigned long irq_flags,const char * devname,void * dev_id)216 int ibmebus_request_irq(u32 ist, irq_handler_t handler,
217 unsigned long irq_flags, const char *devname,
218 void *dev_id)
219 {
220 unsigned int irq = irq_create_mapping(NULL, ist);
221
222 if (irq == NO_IRQ)
223 return -EINVAL;
224
225 return request_irq(irq, handler, irq_flags, devname, dev_id);
226 }
227 EXPORT_SYMBOL(ibmebus_request_irq);
228
ibmebus_free_irq(u32 ist,void * dev_id)229 void ibmebus_free_irq(u32 ist, void *dev_id)
230 {
231 unsigned int irq = irq_find_mapping(NULL, ist);
232
233 free_irq(irq, dev_id);
234 irq_dispose_mapping(irq);
235 }
236 EXPORT_SYMBOL(ibmebus_free_irq);
237
ibmebus_chomp(const char * in,size_t count)238 static char *ibmebus_chomp(const char *in, size_t count)
239 {
240 char *out = kmalloc(count + 1, GFP_KERNEL);
241
242 if (!out)
243 return NULL;
244
245 memcpy(out, in, count);
246 out[count] = '\0';
247 if (out[count - 1] == '\n')
248 out[count - 1] = '\0';
249
250 return out;
251 }
252
ibmebus_store_probe(struct bus_type * bus,const char * buf,size_t count)253 static ssize_t ibmebus_store_probe(struct bus_type *bus,
254 const char *buf, size_t count)
255 {
256 struct device_node *dn = NULL;
257 char *path;
258 ssize_t rc = 0;
259
260 path = ibmebus_chomp(buf, count);
261 if (!path)
262 return -ENOMEM;
263
264 if (bus_find_device(&ibmebus_bus_type, NULL, path,
265 ibmebus_match_path)) {
266 printk(KERN_WARNING "%s: %s has already been probed\n",
267 __func__, path);
268 rc = -EEXIST;
269 goto out;
270 }
271
272 if ((dn = of_find_node_by_path(path))) {
273 rc = ibmebus_create_device(dn);
274 of_node_put(dn);
275 } else {
276 printk(KERN_WARNING "%s: no such device node: %s\n",
277 __func__, path);
278 rc = -ENODEV;
279 }
280
281 out:
282 kfree(path);
283 if (rc)
284 return rc;
285 return count;
286 }
287
ibmebus_store_remove(struct bus_type * bus,const char * buf,size_t count)288 static ssize_t ibmebus_store_remove(struct bus_type *bus,
289 const char *buf, size_t count)
290 {
291 struct device *dev;
292 char *path;
293
294 path = ibmebus_chomp(buf, count);
295 if (!path)
296 return -ENOMEM;
297
298 if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
299 ibmebus_match_path))) {
300 of_device_unregister(to_of_device(dev));
301
302 kfree(path);
303 return count;
304 } else {
305 printk(KERN_WARNING "%s: %s not on the bus\n",
306 __func__, path);
307
308 kfree(path);
309 return -ENODEV;
310 }
311 }
312
313 static struct bus_attribute ibmebus_bus_attrs[] = {
314 __ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe),
315 __ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove),
316 __ATTR_NULL
317 };
318
319 struct bus_type ibmebus_bus_type = {
320 .uevent = of_device_uevent,
321 .bus_attrs = ibmebus_bus_attrs
322 };
323 EXPORT_SYMBOL(ibmebus_bus_type);
324
ibmebus_bus_init(void)325 static int __init ibmebus_bus_init(void)
326 {
327 int err;
328
329 printk(KERN_INFO "IBM eBus Device Driver\n");
330
331 err = of_bus_type_init(&ibmebus_bus_type, "ibmebus");
332 if (err) {
333 printk(KERN_ERR "%s: failed to register IBM eBus.\n",
334 __func__);
335 return err;
336 }
337
338 err = device_register(&ibmebus_bus_device);
339 if (err) {
340 printk(KERN_WARNING "%s: device_register returned %i\n",
341 __func__, err);
342 bus_unregister(&ibmebus_bus_type);
343
344 return err;
345 }
346
347 err = ibmebus_create_devices(ibmebus_matches);
348 if (err) {
349 device_unregister(&ibmebus_bus_device);
350 bus_unregister(&ibmebus_bus_type);
351 return err;
352 }
353
354 return 0;
355 }
356 postcore_initcall(ibmebus_bus_init);
357