xref: /linux/arch/sparc/kernel/prom_common.c (revision cc4589ebfae6f8dbb5cf880a0a67eedab3416492)
1 /* prom_common.c: OF device tree support common code.
2  *
3  * Paul Mackerras	August 1996.
4  * Copyright (C) 1996-2005 Paul Mackerras.
5  *
6  *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
7  *    {engebret|bergner}@us.ibm.com
8  *
9  *  Adapted for sparc by David S. Miller davem@davemloft.net
10  *
11  *      This program is free software; you can redistribute it and/or
12  *      modify it under the terms of the GNU General Public License
13  *      as published by the Free Software Foundation; either version
14  *      2 of the License, or (at your option) any later version.
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/errno.h>
20 #include <linux/mutex.h>
21 #include <linux/slab.h>
22 #include <linux/of.h>
23 #include <asm/prom.h>
24 #include <asm/oplib.h>
25 #include <asm/leon.h>
26 
27 #include "prom.h"
28 
29 void (*prom_build_more)(struct device_node *dp, struct device_node ***nextp);
30 
31 struct device_node *of_console_device;
32 EXPORT_SYMBOL(of_console_device);
33 
34 char *of_console_path;
35 EXPORT_SYMBOL(of_console_path);
36 
37 char *of_console_options;
38 EXPORT_SYMBOL(of_console_options);
39 
40 int of_getintprop_default(struct device_node *np, const char *name, int def)
41 {
42 	struct property *prop;
43 	int len;
44 
45 	prop = of_find_property(np, name, &len);
46 	if (!prop || len != 4)
47 		return def;
48 
49 	return *(int *) prop->value;
50 }
51 EXPORT_SYMBOL(of_getintprop_default);
52 
53 DEFINE_MUTEX(of_set_property_mutex);
54 EXPORT_SYMBOL(of_set_property_mutex);
55 
56 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
57 {
58 	struct property **prevp;
59 	void *new_val;
60 	int err;
61 
62 	new_val = kmalloc(len, GFP_KERNEL);
63 	if (!new_val)
64 		return -ENOMEM;
65 
66 	memcpy(new_val, val, len);
67 
68 	err = -ENODEV;
69 
70 	mutex_lock(&of_set_property_mutex);
71 	write_lock(&devtree_lock);
72 	prevp = &dp->properties;
73 	while (*prevp) {
74 		struct property *prop = *prevp;
75 
76 		if (!strcasecmp(prop->name, name)) {
77 			void *old_val = prop->value;
78 			int ret;
79 
80 			ret = prom_setprop(dp->phandle, name, val, len);
81 
82 			err = -EINVAL;
83 			if (ret >= 0) {
84 				prop->value = new_val;
85 				prop->length = len;
86 
87 				if (OF_IS_DYNAMIC(prop))
88 					kfree(old_val);
89 
90 				OF_MARK_DYNAMIC(prop);
91 
92 				err = 0;
93 			}
94 			break;
95 		}
96 		prevp = &(*prevp)->next;
97 	}
98 	write_unlock(&devtree_lock);
99 	mutex_unlock(&of_set_property_mutex);
100 
101 	/* XXX Upate procfs if necessary... */
102 
103 	return err;
104 }
105 EXPORT_SYMBOL(of_set_property);
106 
107 int of_find_in_proplist(const char *list, const char *match, int len)
108 {
109 	while (len > 0) {
110 		int l;
111 
112 		if (!strcmp(list, match))
113 			return 1;
114 		l = strlen(list) + 1;
115 		list += l;
116 		len -= l;
117 	}
118 	return 0;
119 }
120 EXPORT_SYMBOL(of_find_in_proplist);
121 
122 unsigned int prom_unique_id;
123 
124 static struct property * __init build_one_prop(phandle node, char *prev,
125 					       char *special_name,
126 					       void *special_val,
127 					       int special_len)
128 {
129 	static struct property *tmp = NULL;
130 	struct property *p;
131 	const char *name;
132 
133 	if (tmp) {
134 		p = tmp;
135 		memset(p, 0, sizeof(*p) + 32);
136 		tmp = NULL;
137 	} else {
138 		p = prom_early_alloc(sizeof(struct property) + 32);
139 		p->unique_id = prom_unique_id++;
140 	}
141 
142 	p->name = (char *) (p + 1);
143 	if (special_name) {
144 		strcpy(p->name, special_name);
145 		p->length = special_len;
146 		p->value = prom_early_alloc(special_len);
147 		memcpy(p->value, special_val, special_len);
148 	} else {
149 		if (prev == NULL) {
150 			name = prom_firstprop(node, p->name);
151 		} else {
152 			name = prom_nextprop(node, prev, p->name);
153 		}
154 
155 		if (!name || strlen(name) == 0) {
156 			tmp = p;
157 			return NULL;
158 		}
159 #ifdef CONFIG_SPARC32
160 		strcpy(p->name, name);
161 #endif
162 		p->length = prom_getproplen(node, p->name);
163 		if (p->length <= 0) {
164 			p->length = 0;
165 		} else {
166 			int len;
167 
168 			p->value = prom_early_alloc(p->length + 1);
169 			len = prom_getproperty(node, p->name, p->value,
170 					       p->length);
171 			if (len <= 0)
172 				p->length = 0;
173 			((unsigned char *)p->value)[p->length] = '\0';
174 		}
175 	}
176 	return p;
177 }
178 
179 static struct property * __init build_prop_list(phandle node)
180 {
181 	struct property *head, *tail;
182 
183 	head = tail = build_one_prop(node, NULL,
184 				     ".node", &node, sizeof(node));
185 
186 	tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
187 	tail = tail->next;
188 	while(tail) {
189 		tail->next = build_one_prop(node, tail->name,
190 					    NULL, NULL, 0);
191 		tail = tail->next;
192 	}
193 
194 	return head;
195 }
196 
197 static char * __init get_one_property(phandle node, const char *name)
198 {
199 	char *buf = "<NULL>";
200 	int len;
201 
202 	len = prom_getproplen(node, name);
203 	if (len > 0) {
204 		buf = prom_early_alloc(len);
205 		len = prom_getproperty(node, name, buf, len);
206 	}
207 
208 	return buf;
209 }
210 
211 static struct device_node * __init prom_create_node(phandle node,
212 						    struct device_node *parent)
213 {
214 	struct device_node *dp;
215 
216 	if (!node)
217 		return NULL;
218 
219 	dp = prom_early_alloc(sizeof(*dp));
220 	dp->unique_id = prom_unique_id++;
221 	dp->parent = parent;
222 
223 	kref_init(&dp->kref);
224 
225 	dp->name = get_one_property(node, "name");
226 	dp->type = get_one_property(node, "device_type");
227 	dp->phandle = node;
228 
229 	dp->properties = build_prop_list(node);
230 
231 	irq_trans_init(dp);
232 
233 	return dp;
234 }
235 
236 char * __init build_full_name(struct device_node *dp)
237 {
238 	int len, ourlen, plen;
239 	char *n;
240 
241 	plen = strlen(dp->parent->full_name);
242 	ourlen = strlen(dp->path_component_name);
243 	len = ourlen + plen + 2;
244 
245 	n = prom_early_alloc(len);
246 	strcpy(n, dp->parent->full_name);
247 	if (!of_node_is_root(dp->parent)) {
248 		strcpy(n + plen, "/");
249 		plen++;
250 	}
251 	strcpy(n + plen, dp->path_component_name);
252 
253 	return n;
254 }
255 
256 static struct device_node * __init prom_build_tree(struct device_node *parent,
257 						   phandle node,
258 						   struct device_node ***nextp)
259 {
260 	struct device_node *ret = NULL, *prev_sibling = NULL;
261 	struct device_node *dp;
262 
263 	while (1) {
264 		dp = prom_create_node(node, parent);
265 		if (!dp)
266 			break;
267 
268 		if (prev_sibling)
269 			prev_sibling->sibling = dp;
270 
271 		if (!ret)
272 			ret = dp;
273 		prev_sibling = dp;
274 
275 		*(*nextp) = dp;
276 		*nextp = &dp->allnext;
277 
278 		dp->path_component_name = build_path_component(dp);
279 		dp->full_name = build_full_name(dp);
280 
281 		dp->child = prom_build_tree(dp, prom_getchild(node), nextp);
282 
283 		if (prom_build_more)
284 			prom_build_more(dp, nextp);
285 
286 		node = prom_getsibling(node);
287 	}
288 
289 	return ret;
290 }
291 
292 unsigned int prom_early_allocated __initdata;
293 
294 void __init prom_build_devicetree(void)
295 {
296 	struct device_node **nextp;
297 
298 	allnodes = prom_create_node(prom_root_node, NULL);
299 	allnodes->path_component_name = "";
300 	allnodes->full_name = "/";
301 
302 	nextp = &allnodes->allnext;
303 	allnodes->child = prom_build_tree(allnodes,
304 					  prom_getchild(allnodes->phandle),
305 					  &nextp);
306 	of_console_init();
307 
308 	printk("PROM: Built device tree with %u bytes of memory.\n",
309 	       prom_early_allocated);
310 }
311