1/*
2 * tree.c: Basic device tree traversal/scanning for the Linux
3 *         prom library.
4 *
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6 * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
7 */
8
9#include <linux/string.h>
10#include <linux/types.h>
11#include <linux/kernel.h>
12#include <linux/sched.h>
13#include <linux/module.h>
14
15#include <asm/openprom.h>
16#include <asm/oplib.h>
17#include <asm/ldc.h>
18
19static phandle prom_node_to_node(const char *type, phandle node)
20{
21	unsigned long args[5];
22
23	args[0] = (unsigned long) type;
24	args[1] = 1;
25	args[2] = 1;
26	args[3] = (unsigned int) node;
27	args[4] = (unsigned long) -1;
28
29	p1275_cmd_direct(args);
30
31	return (phandle) args[4];
32}
33
34/* Return the child of node 'node' or zero if no this node has no
35 * direct descendent.
36 */
37inline phandle __prom_getchild(phandle node)
38{
39	return prom_node_to_node("child", node);
40}
41
42phandle prom_getchild(phandle node)
43{
44	phandle cnode;
45
46	if ((s32)node == -1)
47		return 0;
48	cnode = __prom_getchild(node);
49	if ((s32)cnode == -1)
50		return 0;
51	return cnode;
52}
53EXPORT_SYMBOL(prom_getchild);
54
55inline phandle prom_getparent(phandle node)
56{
57	phandle cnode;
58
59	if ((s32)node == -1)
60		return 0;
61	cnode = prom_node_to_node("parent", node);
62	if ((s32)cnode == -1)
63		return 0;
64	return cnode;
65}
66
67/* Return the next sibling of node 'node' or zero if no more siblings
68 * at this level of depth in the tree.
69 */
70inline phandle __prom_getsibling(phandle node)
71{
72	return prom_node_to_node(prom_peer_name, node);
73}
74
75phandle prom_getsibling(phandle node)
76{
77	phandle sibnode;
78
79	if ((s32)node == -1)
80		return 0;
81	sibnode = __prom_getsibling(node);
82	if ((s32)sibnode == -1)
83		return 0;
84
85	return sibnode;
86}
87EXPORT_SYMBOL(prom_getsibling);
88
89/* Return the length in bytes of property 'prop' at node 'node'.
90 * Return -1 on error.
91 */
92int prom_getproplen(phandle node, const char *prop)
93{
94	unsigned long args[6];
95
96	if (!node || !prop)
97		return -1;
98
99	args[0] = (unsigned long) "getproplen";
100	args[1] = 2;
101	args[2] = 1;
102	args[3] = (unsigned int) node;
103	args[4] = (unsigned long) prop;
104	args[5] = (unsigned long) -1;
105
106	p1275_cmd_direct(args);
107
108	return (int) args[5];
109}
110EXPORT_SYMBOL(prom_getproplen);
111
112/* Acquire a property 'prop' at node 'node' and place it in
113 * 'buffer' which has a size of 'bufsize'.  If the acquisition
114 * was successful the length will be returned, else -1 is returned.
115 */
116int prom_getproperty(phandle node, const char *prop,
117		     char *buffer, int bufsize)
118{
119	unsigned long args[8];
120	int plen;
121
122	plen = prom_getproplen(node, prop);
123	if ((plen > bufsize) || (plen == 0) || (plen == -1))
124		return -1;
125
126	args[0] = (unsigned long) prom_getprop_name;
127	args[1] = 4;
128	args[2] = 1;
129	args[3] = (unsigned int) node;
130	args[4] = (unsigned long) prop;
131	args[5] = (unsigned long) buffer;
132	args[6] = bufsize;
133	args[7] = (unsigned long) -1;
134
135	p1275_cmd_direct(args);
136
137	return (int) args[7];
138}
139EXPORT_SYMBOL(prom_getproperty);
140
141/* Acquire an integer property and return its value.  Returns -1
142 * on failure.
143 */
144int prom_getint(phandle node, const char *prop)
145{
146	int intprop;
147
148	if (prom_getproperty(node, prop, (char *) &intprop, sizeof(int)) != -1)
149		return intprop;
150
151	return -1;
152}
153EXPORT_SYMBOL(prom_getint);
154
155/* Acquire an integer property, upon error return the passed default
156 * integer.
157 */
158
159int prom_getintdefault(phandle node, const char *property, int deflt)
160{
161	int retval;
162
163	retval = prom_getint(node, property);
164	if (retval == -1)
165		return deflt;
166
167	return retval;
168}
169EXPORT_SYMBOL(prom_getintdefault);
170
171/* Acquire a boolean property, 1=TRUE 0=FALSE. */
172int prom_getbool(phandle node, const char *prop)
173{
174	int retval;
175
176	retval = prom_getproplen(node, prop);
177	if (retval == -1)
178		return 0;
179	return 1;
180}
181EXPORT_SYMBOL(prom_getbool);
182
183/* Acquire a property whose value is a string, returns a null
184 * string on error.  The char pointer is the user supplied string
185 * buffer.
186 */
187void prom_getstring(phandle node, const char *prop, char *user_buf,
188		int ubuf_size)
189{
190	int len;
191
192	len = prom_getproperty(node, prop, user_buf, ubuf_size);
193	if (len != -1)
194		return;
195	user_buf[0] = 0;
196}
197EXPORT_SYMBOL(prom_getstring);
198
199/* Does the device at node 'node' have name 'name'?
200 * YES = 1   NO = 0
201 */
202int prom_nodematch(phandle node, const char *name)
203{
204	char namebuf[128];
205	prom_getproperty(node, "name", namebuf, sizeof(namebuf));
206	if (strcmp(namebuf, name) == 0)
207		return 1;
208	return 0;
209}
210
211/* Search siblings at 'node_start' for a node with name
212 * 'nodename'.  Return node if successful, zero if not.
213 */
214phandle prom_searchsiblings(phandle node_start, const char *nodename)
215{
216	phandle thisnode;
217	int error;
218	char promlib_buf[128];
219
220	for(thisnode = node_start; thisnode;
221	    thisnode=prom_getsibling(thisnode)) {
222		error = prom_getproperty(thisnode, "name", promlib_buf,
223					 sizeof(promlib_buf));
224		/* Should this ever happen? */
225		if(error == -1) continue;
226		if(strcmp(nodename, promlib_buf)==0) return thisnode;
227	}
228
229	return 0;
230}
231EXPORT_SYMBOL(prom_searchsiblings);
232
233static const char *prom_nextprop_name = "nextprop";
234
235/* Return the first property type for node 'node'.
236 * buffer should be at least 32B in length
237 */
238char *prom_firstprop(phandle node, char *buffer)
239{
240	unsigned long args[7];
241
242	*buffer = 0;
243	if ((s32)node == -1)
244		return buffer;
245
246	args[0] = (unsigned long) prom_nextprop_name;
247	args[1] = 3;
248	args[2] = 1;
249	args[3] = (unsigned int) node;
250	args[4] = 0;
251	args[5] = (unsigned long) buffer;
252	args[6] = (unsigned long) -1;
253
254	p1275_cmd_direct(args);
255
256	return buffer;
257}
258EXPORT_SYMBOL(prom_firstprop);
259
260/* Return the property type string after property type 'oprop'
261 * at node 'node' .  Returns NULL string if no more
262 * property types for this node.
263 */
264char *prom_nextprop(phandle node, const char *oprop, char *buffer)
265{
266	unsigned long args[7];
267	char buf[32];
268
269	if ((s32)node == -1) {
270		*buffer = 0;
271		return buffer;
272	}
273	if (oprop == buffer) {
274		strcpy (buf, oprop);
275		oprop = buf;
276	}
277
278	args[0] = (unsigned long) prom_nextprop_name;
279	args[1] = 3;
280	args[2] = 1;
281	args[3] = (unsigned int) node;
282	args[4] = (unsigned long) oprop;
283	args[5] = (unsigned long) buffer;
284	args[6] = (unsigned long) -1;
285
286	p1275_cmd_direct(args);
287
288	return buffer;
289}
290EXPORT_SYMBOL(prom_nextprop);
291
292phandle prom_finddevice(const char *name)
293{
294	unsigned long args[5];
295
296	if (!name)
297		return 0;
298	args[0] = (unsigned long) "finddevice";
299	args[1] = 1;
300	args[2] = 1;
301	args[3] = (unsigned long) name;
302	args[4] = (unsigned long) -1;
303
304	p1275_cmd_direct(args);
305
306	return (int) args[4];
307}
308EXPORT_SYMBOL(prom_finddevice);
309
310int prom_node_has_property(phandle node, const char *prop)
311{
312	char buf [32];
313
314	*buf = 0;
315	do {
316		prom_nextprop(node, buf, buf);
317		if (!strcmp(buf, prop))
318			return 1;
319	} while (*buf);
320	return 0;
321}
322EXPORT_SYMBOL(prom_node_has_property);
323
324/* Set property 'pname' at node 'node' to value 'value' which has a length
325 * of 'size' bytes.  Return the number of bytes the prom accepted.
326 */
327int
328prom_setprop(phandle node, const char *pname, char *value, int size)
329{
330	unsigned long args[8];
331
332	if (size == 0)
333		return 0;
334	if ((pname == 0) || (value == 0))
335		return 0;
336
337#ifdef CONFIG_SUN_LDOMS
338	if (ldom_domaining_enabled) {
339		ldom_set_var(pname, value);
340		return 0;
341	}
342#endif
343	args[0] = (unsigned long) "setprop";
344	args[1] = 4;
345	args[2] = 1;
346	args[3] = (unsigned int) node;
347	args[4] = (unsigned long) pname;
348	args[5] = (unsigned long) value;
349	args[6] = size;
350	args[7] = (unsigned long) -1;
351
352	p1275_cmd_direct(args);
353
354	return (int) args[7];
355}
356EXPORT_SYMBOL(prom_setprop);
357
358inline phandle prom_inst2pkg(int inst)
359{
360	unsigned long args[5];
361	phandle node;
362
363	args[0] = (unsigned long) "instance-to-package";
364	args[1] = 1;
365	args[2] = 1;
366	args[3] = (unsigned int) inst;
367	args[4] = (unsigned long) -1;
368
369	p1275_cmd_direct(args);
370
371	node = (int) args[4];
372	if ((s32)node == -1)
373		return 0;
374	return node;
375}
376
377int prom_ihandle2path(int handle, char *buffer, int bufsize)
378{
379	unsigned long args[7];
380
381	args[0] = (unsigned long) "instance-to-path";
382	args[1] = 3;
383	args[2] = 1;
384	args[3] = (unsigned int) handle;
385	args[4] = (unsigned long) buffer;
386	args[5] = bufsize;
387	args[6] = (unsigned long) -1;
388
389	p1275_cmd_direct(args);
390
391	return (int) args[6];
392}
393