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.bus = &of_platform_bus_type;
80 
81 	/* We do not fill the DMA ops for platform devices by default.
82 	 * This is currently the responsibility of the platform code
83 	 * to do such, possibly using a device notifier
84 	 */
85 
86 	if (of_device_register(dev) != 0) {
87 		of_device_free(dev);
88 		return NULL;
89 	}
90 
91 	return dev;
92 }
93 EXPORT_SYMBOL(of_platform_device_create);
94 
95 
96 
97 /**
98  * of_platform_bus_create - Create an OF device for a bus node and all its
99  * children. Optionally recursively instanciate matching busses.
100  * @bus: device node of the bus to instanciate
101  * @matches: match table, NULL to use the default, OF_NO_DEEP_PROBE to
102  * disallow recursive creation of child busses
103  */
104 static int of_platform_bus_create(const struct device_node *bus,
105 				  const struct of_device_id *matches,
106 				  struct device *parent)
107 {
108 	struct device_node *child;
109 	struct of_device *dev;
110 	int rc = 0;
111 
112 	for_each_child_of_node(bus, child) {
113 		pr_debug("   create child: %s\n", child->full_name);
114 		dev = of_platform_device_create(child, NULL, parent);
115 		if (dev == NULL)
116 			rc = -ENOMEM;
117 		else if (!of_match_node(matches, child))
118 			continue;
119 		if (rc == 0) {
120 			pr_debug("   and sub busses\n");
121 			rc = of_platform_bus_create(child, matches, &dev->dev);
122 		} if (rc) {
123 			of_node_put(child);
124 			break;
125 		}
126 	}
127 	return rc;
128 }
129 
130 /**
131  * of_platform_bus_probe - Probe the device-tree for platform busses
132  * @root: parent of the first level to probe or NULL for the root of the tree
133  * @matches: match table, NULL to use the default
134  * @parent: parent to hook devices from, NULL for toplevel
135  *
136  * Note that children of the provided root are not instanciated as devices
137  * unless the specified root itself matches the bus list and is not NULL.
138  */
139 
140 int of_platform_bus_probe(struct device_node *root,
141 			  const struct of_device_id *matches,
142 			  struct device *parent)
143 {
144 	struct device_node *child;
145 	struct of_device *dev;
146 	int rc = 0;
147 
148 	if (matches == NULL)
149 		matches = of_default_bus_ids;
150 	if (matches == OF_NO_DEEP_PROBE)
151 		return -EINVAL;
152 	if (root == NULL)
153 		root = of_find_node_by_path("/");
154 	else
155 		of_node_get(root);
156 
157 	pr_debug("of_platform_bus_probe()\n");
158 	pr_debug(" starting at: %s\n", root->full_name);
159 
160 	/* Do a self check of bus type, if there's a match, create
161 	 * children
162 	 */
163 	if (of_match_node(matches, root)) {
164 		pr_debug(" root match, create all sub devices\n");
165 		dev = of_platform_device_create(root, NULL, parent);
166 		if (dev == NULL) {
167 			rc = -ENOMEM;
168 			goto bail;
169 		}
170 		pr_debug(" create all sub busses\n");
171 		rc = of_platform_bus_create(root, matches, &dev->dev);
172 		goto bail;
173 	}
174 	for_each_child_of_node(root, child) {
175 		if (!of_match_node(matches, child))
176 			continue;
177 
178 		pr_debug("  match: %s\n", child->full_name);
179 		dev = of_platform_device_create(child, NULL, parent);
180 		if (dev == NULL)
181 			rc = -ENOMEM;
182 		else
183 			rc = of_platform_bus_create(child, matches, &dev->dev);
184 		if (rc) {
185 			of_node_put(child);
186 			break;
187 		}
188 	}
189  bail:
190 	of_node_put(root);
191 	return rc;
192 }
193 EXPORT_SYMBOL(of_platform_bus_probe);
194 
195 static int of_dev_node_match(struct device *dev, void *data)
196 {
197 	return to_of_device(dev)->node == data;
198 }
199 
200 struct of_device *of_find_device_by_node(struct device_node *np)
201 {
202 	struct device *dev;
203 
204 	dev = bus_find_device(&of_platform_bus_type,
205 			      NULL, np, of_dev_node_match);
206 	if (dev)
207 		return to_of_device(dev);
208 	return NULL;
209 }
210 EXPORT_SYMBOL(of_find_device_by_node);
211 
212 static int of_dev_phandle_match(struct device *dev, void *data)
213 {
214 	phandle *ph = data;
215 	return to_of_device(dev)->node->linux_phandle == *ph;
216 }
217 
218 struct of_device *of_find_device_by_phandle(phandle ph)
219 {
220 	struct device *dev;
221 
222 	dev = bus_find_device(&of_platform_bus_type,
223 			      NULL, &ph, of_dev_phandle_match);
224 	if (dev)
225 		return to_of_device(dev);
226 	return NULL;
227 }
228 EXPORT_SYMBOL(of_find_device_by_phandle);
229 
230 
231 #ifdef CONFIG_PPC_OF_PLATFORM_PCI
232 
233 /* The probing of PCI controllers from of_platform is currently
234  * 64 bits only, mostly due to gratuitous differences between
235  * the 32 and 64 bits PCI code on PowerPC and the 32 bits one
236  * lacking some bits needed here.
237  */
238 
239 static int __devinit of_pci_phb_probe(struct of_device *dev,
240 				      const struct of_device_id *match)
241 {
242 	struct pci_controller *phb;
243 
244 	/* Check if we can do that ... */
245 	if (ppc_md.pci_setup_phb == NULL)
246 		return -ENODEV;
247 
248 	printk(KERN_INFO "Setting up PCI bus %s\n", dev->node->full_name);
249 
250 	/* Alloc and setup PHB data structure */
251 	phb = pcibios_alloc_controller(dev->node);
252 	if (!phb)
253 		return -ENODEV;
254 
255 	/* Setup parent in sysfs */
256 	phb->parent = &dev->dev;
257 
258 	/* Setup the PHB using arch provided callback */
259 	if (ppc_md.pci_setup_phb(phb)) {
260 		pcibios_free_controller(phb);
261 		return -ENODEV;
262 	}
263 
264 	/* Process "ranges" property */
265 	pci_process_bridge_OF_ranges(phb, dev->node, 0);
266 
267 	/* Init pci_dn data structures */
268 	pci_devs_phb_init_dynamic(phb);
269 
270 	/* Register devices with EEH */
271 #ifdef CONFIG_EEH
272 	if (dev->node->child)
273 		eeh_add_device_tree_early(dev->node);
274 #endif /* CONFIG_EEH */
275 
276 	/* Scan the bus */
277 	scan_phb(phb);
278 
279 	/* Claim resources. This might need some rework as well depending
280 	 * wether we are doing probe-only or not, like assigning unassigned
281 	 * resources etc...
282 	 */
283 	pcibios_claim_one_bus(phb->bus);
284 
285 	/* Finish EEH setup */
286 #ifdef CONFIG_EEH
287 	eeh_add_device_tree_late(phb->bus);
288 #endif
289 
290 	/* Add probed PCI devices to the device model */
291 	pci_bus_add_devices(phb->bus);
292 
293 	return 0;
294 }
295 
296 static struct of_device_id of_pci_phb_ids[] = {
297 	{ .type = "pci", },
298 	{ .type = "pcix", },
299 	{ .type = "pcie", },
300 	{ .type = "pciex", },
301 	{ .type = "ht", },
302 	{}
303 };
304 
305 static struct of_platform_driver of_pci_phb_driver = {
306 	.match_table = of_pci_phb_ids,
307 	.probe = of_pci_phb_probe,
308 	.driver = {
309 		.name = "of-pci",
310 	},
311 };
312 
313 static __init int of_pci_phb_init(void)
314 {
315 	return of_register_platform_driver(&of_pci_phb_driver);
316 }
317 
318 device_initcall(of_pci_phb_init);
319 
320 #endif /* CONFIG_PPC_OF_PLATFORM_PCI */
321