1 /*
2  *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
3  *			 <benh@kernel.crashing.org>
4  *    and		 Arnd Bergmann, IBM Corp.
5  *
6  *  This program is free software; you can redistribute it and/or
7  *  modify it under the terms of the GNU General Public License
8  *  as published by the Free Software Foundation; either version
9  *  2 of the License, or (at your option) any later version.
10  *
11  */
12 
13 #undef DEBUG
14 
15 #include <linux/string.h>
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/slab.h>
21 #include <linux/pci.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/of_platform.h>
25 
26 #include <asm/errno.h>
27 #include <asm/topology.h>
28 #include <asm/pci-bridge.h>
29 #include <asm/ppc-pci.h>
30 #include <asm/atomic.h>
31 
32 /*
33  * The list of OF IDs below is used for matching bus types in the
34  * system whose devices are to be exposed as of_platform_devices.
35  *
36  * This is the default list valid for most platforms. This file provides
37  * functions who can take an explicit list if necessary though
38  *
39  * The search is always performed recursively looking for children of
40  * the provided device_node and recursively if such a children matches
41  * a bus type in the list
42  */
43 
44 static const struct of_device_id of_default_bus_ids[] = {
45 	{ .type = "soc", },
46 	{ .compatible = "soc", },
47 	{ .type = "spider", },
48 	{ .type = "axon", },
49 	{ .type = "plb5", },
50 	{ .type = "plb4", },
51 	{ .type = "opb", },
52 	{ .type = "ebc", },
53 	{},
54 };
55 
56 struct bus_type of_platform_bus_type = {
57        .uevent	= of_device_uevent,
58 };
59 EXPORT_SYMBOL(of_platform_bus_type);
60 
61 static int __init of_bus_driver_init(void)
62 {
63 	return of_bus_type_init(&of_platform_bus_type, "of_platform");
64 }
65 
66 postcore_initcall(of_bus_driver_init);
67 
68 struct of_device* of_platform_device_create(struct device_node *np,
69 					    const char *bus_id,
70 					    struct device *parent)
71 {
72 	struct of_device *dev;
73 
74 	dev = of_device_alloc(np, bus_id, parent);
75 	if (!dev)
76 		return NULL;
77 
78 	dev->dma_mask = 0xffffffffUL;
79 	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
80 
81 	dev->dev.bus = &of_platform_bus_type;
82 
83 	/* We do not fill the DMA ops for platform devices by default.
84 	 * This is currently the responsibility of the platform code
85 	 * to do such, possibly using a device notifier
86 	 */
87 
88 	if (of_device_register(dev) != 0) {
89 		of_device_free(dev);
90 		return NULL;
91 	}
92 
93 	return dev;
94 }
95 EXPORT_SYMBOL(of_platform_device_create);
96 
97 
98 
99 /**
100  * of_platform_bus_create - Create an OF device for a bus node and all its
101  * children. Optionally recursively instanciate matching busses.
102  * @bus: device node of the bus to instanciate
103  * @matches: match table, NULL to use the default, OF_NO_DEEP_PROBE to
104  * disallow recursive creation of child busses
105  */
106 static int of_platform_bus_create(const struct device_node *bus,
107 				  const struct of_device_id *matches,
108 				  struct device *parent)
109 {
110 	struct device_node *child;
111 	struct of_device *dev;
112 	int rc = 0;
113 
114 	for_each_child_of_node(bus, child) {
115 		pr_debug("   create child: %s\n", child->full_name);
116 		dev = of_platform_device_create(child, NULL, parent);
117 		if (dev == NULL)
118 			rc = -ENOMEM;
119 		else if (!of_match_node(matches, child))
120 			continue;
121 		if (rc == 0) {
122 			pr_debug("   and sub busses\n");
123 			rc = of_platform_bus_create(child, matches, &dev->dev);
124 		} if (rc) {
125 			of_node_put(child);
126 			break;
127 		}
128 	}
129 	return rc;
130 }
131 
132 /**
133  * of_platform_bus_probe - Probe the device-tree for platform busses
134  * @root: parent of the first level to probe or NULL for the root of the tree
135  * @matches: match table, NULL to use the default
136  * @parent: parent to hook devices from, NULL for toplevel
137  *
138  * Note that children of the provided root are not instanciated as devices
139  * unless the specified root itself matches the bus list and is not NULL.
140  */
141 
142 int of_platform_bus_probe(struct device_node *root,
143 			  const struct of_device_id *matches,
144 			  struct device *parent)
145 {
146 	struct device_node *child;
147 	struct of_device *dev;
148 	int rc = 0;
149 
150 	if (matches == NULL)
151 		matches = of_default_bus_ids;
152 	if (matches == OF_NO_DEEP_PROBE)
153 		return -EINVAL;
154 	if (root == NULL)
155 		root = of_find_node_by_path("/");
156 	else
157 		of_node_get(root);
158 
159 	pr_debug("of_platform_bus_probe()\n");
160 	pr_debug(" starting at: %s\n", root->full_name);
161 
162 	/* Do a self check of bus type, if there's a match, create
163 	 * children
164 	 */
165 	if (of_match_node(matches, root)) {
166 		pr_debug(" root match, create all sub devices\n");
167 		dev = of_platform_device_create(root, NULL, parent);
168 		if (dev == NULL) {
169 			rc = -ENOMEM;
170 			goto bail;
171 		}
172 		pr_debug(" create all sub busses\n");
173 		rc = of_platform_bus_create(root, matches, &dev->dev);
174 		goto bail;
175 	}
176 	for_each_child_of_node(root, child) {
177 		if (!of_match_node(matches, child))
178 			continue;
179 
180 		pr_debug("  match: %s\n", child->full_name);
181 		dev = of_platform_device_create(child, NULL, parent);
182 		if (dev == NULL)
183 			rc = -ENOMEM;
184 		else
185 			rc = of_platform_bus_create(child, matches, &dev->dev);
186 		if (rc) {
187 			of_node_put(child);
188 			break;
189 		}
190 	}
191  bail:
192 	of_node_put(root);
193 	return rc;
194 }
195 EXPORT_SYMBOL(of_platform_bus_probe);
196 
197 static int of_dev_node_match(struct device *dev, void *data)
198 {
199 	return to_of_device(dev)->node == data;
200 }
201 
202 struct of_device *of_find_device_by_node(struct device_node *np)
203 {
204 	struct device *dev;
205 
206 	dev = bus_find_device(&of_platform_bus_type,
207 			      NULL, np, of_dev_node_match);
208 	if (dev)
209 		return to_of_device(dev);
210 	return NULL;
211 }
212 EXPORT_SYMBOL(of_find_device_by_node);
213 
214 static int of_dev_phandle_match(struct device *dev, void *data)
215 {
216 	phandle *ph = data;
217 	return to_of_device(dev)->node->linux_phandle == *ph;
218 }
219 
220 struct of_device *of_find_device_by_phandle(phandle ph)
221 {
222 	struct device *dev;
223 
224 	dev = bus_find_device(&of_platform_bus_type,
225 			      NULL, &ph, of_dev_phandle_match);
226 	if (dev)
227 		return to_of_device(dev);
228 	return NULL;
229 }
230 EXPORT_SYMBOL(of_find_device_by_phandle);
231 
232 
233 #ifdef CONFIG_PPC_OF_PLATFORM_PCI
234 
235 /* The probing of PCI controllers from of_platform is currently
236  * 64 bits only, mostly due to gratuitous differences between
237  * the 32 and 64 bits PCI code on PowerPC and the 32 bits one
238  * lacking some bits needed here.
239  */
240 
241 static int __devinit of_pci_phb_probe(struct of_device *dev,
242 				      const struct of_device_id *match)
243 {
244 	struct pci_controller *phb;
245 
246 	/* Check if we can do that ... */
247 	if (ppc_md.pci_setup_phb == NULL)
248 		return -ENODEV;
249 
250 	printk(KERN_INFO "Setting up PCI bus %s\n", dev->node->full_name);
251 
252 	/* Alloc and setup PHB data structure */
253 	phb = pcibios_alloc_controller(dev->node);
254 	if (!phb)
255 		return -ENODEV;
256 
257 	/* Setup parent in sysfs */
258 	phb->parent = &dev->dev;
259 
260 	/* Setup the PHB using arch provided callback */
261 	if (ppc_md.pci_setup_phb(phb)) {
262 		pcibios_free_controller(phb);
263 		return -ENODEV;
264 	}
265 
266 	/* Process "ranges" property */
267 	pci_process_bridge_OF_ranges(phb, dev->node, 0);
268 
269 	/* Init pci_dn data structures */
270 	pci_devs_phb_init_dynamic(phb);
271 
272 	/* Register devices with EEH */
273 #ifdef CONFIG_EEH
274 	if (dev->node->child)
275 		eeh_add_device_tree_early(dev->node);
276 #endif /* CONFIG_EEH */
277 
278 	/* Scan the bus */
279 	pcibios_scan_phb(phb, dev->node);
280 	if (phb->bus == NULL)
281 		return -ENXIO;
282 
283 	/* Claim resources. This might need some rework as well depending
284 	 * wether we are doing probe-only or not, like assigning unassigned
285 	 * resources etc...
286 	 */
287 	pcibios_claim_one_bus(phb->bus);
288 
289 	/* Finish EEH setup */
290 #ifdef CONFIG_EEH
291 	eeh_add_device_tree_late(phb->bus);
292 #endif
293 
294 	/* Add probed PCI devices to the device model */
295 	pci_bus_add_devices(phb->bus);
296 
297 	return 0;
298 }
299 
300 static struct of_device_id of_pci_phb_ids[] = {
301 	{ .type = "pci", },
302 	{ .type = "pcix", },
303 	{ .type = "pcie", },
304 	{ .type = "pciex", },
305 	{ .type = "ht", },
306 	{}
307 };
308 
309 static struct of_platform_driver of_pci_phb_driver = {
310 	.match_table = of_pci_phb_ids,
311 	.probe = of_pci_phb_probe,
312 	.driver = {
313 		.name = "of-pci",
314 	},
315 };
316 
317 static __init int of_pci_phb_init(void)
318 {
319 	return of_register_platform_driver(&of_pci_phb_driver);
320 }
321 
322 device_initcall(of_pci_phb_init);
323 
324 #endif /* CONFIG_PPC_OF_PLATFORM_PCI */
325