Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
88278ca2 | 2 | /* |
1da177e4 LT |
3 | * tree.c: Basic device tree traversal/scanning for the Linux |
4 | * prom library. | |
5 | * | |
6 | * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) | |
7 | */ | |
8 | ||
1da177e4 LT |
9 | #include <linux/string.h> |
10 | #include <linux/types.h> | |
11 | #include <linux/kernel.h> | |
12 | #include <linux/sched.h> | |
13 | #include <linux/ctype.h> | |
6943f3da | 14 | #include <linux/module.h> |
1da177e4 LT |
15 | |
16 | #include <asm/openprom.h> | |
17 | #include <asm/oplib.h> | |
18 | ||
19 | extern void restore_current(void); | |
20 | ||
21 | static char promlib_buf[128]; | |
22 | ||
23 | /* Internal version of prom_getchild that does not alter return values. */ | |
1f42be48 | 24 | static phandle __prom_getchild(phandle node) |
1da177e4 LT |
25 | { |
26 | unsigned long flags; | |
8d125562 | 27 | phandle cnode; |
1da177e4 LT |
28 | |
29 | spin_lock_irqsave(&prom_lock, flags); | |
30 | cnode = prom_nodeops->no_child(node); | |
31 | restore_current(); | |
32 | spin_unlock_irqrestore(&prom_lock, flags); | |
33 | ||
34 | return cnode; | |
35 | } | |
36 | ||
37 | /* Return the child of node 'node' or zero if no this node has no | |
38 | * direct descendent. | |
39 | */ | |
8d125562 | 40 | phandle prom_getchild(phandle node) |
1da177e4 | 41 | { |
8d125562 | 42 | phandle cnode; |
1da177e4 | 43 | |
4a3a2552 | 44 | if ((s32)node == -1) |
1da177e4 LT |
45 | return 0; |
46 | ||
47 | cnode = __prom_getchild(node); | |
4a3a2552 | 48 | if (cnode == 0 || (s32)cnode == -1) |
1da177e4 LT |
49 | return 0; |
50 | ||
51 | return cnode; | |
52 | } | |
6943f3da | 53 | EXPORT_SYMBOL(prom_getchild); |
1da177e4 LT |
54 | |
55 | /* Internal version of prom_getsibling that does not alter return values. */ | |
1f42be48 | 56 | static phandle __prom_getsibling(phandle node) |
1da177e4 LT |
57 | { |
58 | unsigned long flags; | |
8d125562 | 59 | phandle cnode; |
1da177e4 LT |
60 | |
61 | spin_lock_irqsave(&prom_lock, flags); | |
62 | cnode = prom_nodeops->no_nextnode(node); | |
63 | restore_current(); | |
64 | spin_unlock_irqrestore(&prom_lock, flags); | |
65 | ||
66 | return cnode; | |
67 | } | |
68 | ||
69 | /* Return the next sibling of node 'node' or zero if no more siblings | |
70 | * at this level of depth in the tree. | |
71 | */ | |
8d125562 | 72 | phandle prom_getsibling(phandle node) |
1da177e4 | 73 | { |
8d125562 | 74 | phandle sibnode; |
1da177e4 | 75 | |
4a3a2552 | 76 | if ((s32)node == -1) |
1da177e4 LT |
77 | return 0; |
78 | ||
79 | sibnode = __prom_getsibling(node); | |
4a3a2552 | 80 | if (sibnode == 0 || (s32)sibnode == -1) |
1da177e4 LT |
81 | return 0; |
82 | ||
83 | return sibnode; | |
84 | } | |
6943f3da | 85 | EXPORT_SYMBOL(prom_getsibling); |
1da177e4 LT |
86 | |
87 | /* Return the length in bytes of property 'prop' at node 'node'. | |
88 | * Return -1 on error. | |
89 | */ | |
8d125562 | 90 | int prom_getproplen(phandle node, const char *prop) |
1da177e4 LT |
91 | { |
92 | int ret; | |
93 | unsigned long flags; | |
94 | ||
95 | if((!node) || (!prop)) | |
96 | return -1; | |
97 | ||
98 | spin_lock_irqsave(&prom_lock, flags); | |
99 | ret = prom_nodeops->no_proplen(node, prop); | |
100 | restore_current(); | |
101 | spin_unlock_irqrestore(&prom_lock, flags); | |
102 | return ret; | |
103 | } | |
6943f3da | 104 | EXPORT_SYMBOL(prom_getproplen); |
1da177e4 LT |
105 | |
106 | /* Acquire a property 'prop' at node 'node' and place it in | |
107 | * 'buffer' which has a size of 'bufsize'. If the acquisition | |
108 | * was successful the length will be returned, else -1 is returned. | |
109 | */ | |
8d125562 | 110 | int prom_getproperty(phandle node, const char *prop, char *buffer, int bufsize) |
1da177e4 LT |
111 | { |
112 | int plen, ret; | |
113 | unsigned long flags; | |
114 | ||
115 | plen = prom_getproplen(node, prop); | |
116 | if((plen > bufsize) || (plen == 0) || (plen == -1)) | |
117 | return -1; | |
118 | /* Ok, things seem all right. */ | |
119 | spin_lock_irqsave(&prom_lock, flags); | |
120 | ret = prom_nodeops->no_getprop(node, prop, buffer); | |
121 | restore_current(); | |
122 | spin_unlock_irqrestore(&prom_lock, flags); | |
123 | return ret; | |
124 | } | |
6943f3da | 125 | EXPORT_SYMBOL(prom_getproperty); |
1da177e4 LT |
126 | |
127 | /* Acquire an integer property and return its value. Returns -1 | |
128 | * on failure. | |
129 | */ | |
8d125562 | 130 | int prom_getint(phandle node, char *prop) |
1da177e4 LT |
131 | { |
132 | static int intprop; | |
133 | ||
134 | if(prom_getproperty(node, prop, (char *) &intprop, sizeof(int)) != -1) | |
135 | return intprop; | |
136 | ||
137 | return -1; | |
138 | } | |
6943f3da | 139 | EXPORT_SYMBOL(prom_getint); |
1da177e4 LT |
140 | |
141 | /* Acquire an integer property, upon error return the passed default | |
142 | * integer. | |
143 | */ | |
8d125562 | 144 | int prom_getintdefault(phandle node, char *property, int deflt) |
1da177e4 LT |
145 | { |
146 | int retval; | |
147 | ||
148 | retval = prom_getint(node, property); | |
149 | if(retval == -1) return deflt; | |
150 | ||
151 | return retval; | |
152 | } | |
6943f3da | 153 | EXPORT_SYMBOL(prom_getintdefault); |
1da177e4 LT |
154 | |
155 | /* Acquire a boolean property, 1=TRUE 0=FALSE. */ | |
8d125562 | 156 | int prom_getbool(phandle node, char *prop) |
1da177e4 LT |
157 | { |
158 | int retval; | |
159 | ||
160 | retval = prom_getproplen(node, prop); | |
161 | if(retval == -1) return 0; | |
162 | return 1; | |
163 | } | |
6943f3da | 164 | EXPORT_SYMBOL(prom_getbool); |
1da177e4 LT |
165 | |
166 | /* Acquire a property whose value is a string, returns a null | |
167 | * string on error. The char pointer is the user supplied string | |
168 | * buffer. | |
169 | */ | |
8d125562 | 170 | void prom_getstring(phandle node, char *prop, char *user_buf, int ubuf_size) |
1da177e4 LT |
171 | { |
172 | int len; | |
173 | ||
174 | len = prom_getproperty(node, prop, user_buf, ubuf_size); | |
175 | if(len != -1) return; | |
176 | user_buf[0] = 0; | |
1da177e4 | 177 | } |
6943f3da | 178 | EXPORT_SYMBOL(prom_getstring); |
1da177e4 LT |
179 | |
180 | ||
1da177e4 LT |
181 | /* Search siblings at 'node_start' for a node with name |
182 | * 'nodename'. Return node if successful, zero if not. | |
183 | */ | |
8d125562 | 184 | phandle prom_searchsiblings(phandle node_start, char *nodename) |
1da177e4 LT |
185 | { |
186 | ||
8d125562 AS |
187 | phandle thisnode; |
188 | int error; | |
1da177e4 LT |
189 | |
190 | for(thisnode = node_start; thisnode; | |
191 | thisnode=prom_getsibling(thisnode)) { | |
192 | error = prom_getproperty(thisnode, "name", promlib_buf, | |
193 | sizeof(promlib_buf)); | |
194 | /* Should this ever happen? */ | |
195 | if(error == -1) continue; | |
196 | if(strcmp(nodename, promlib_buf)==0) return thisnode; | |
197 | } | |
198 | ||
199 | return 0; | |
200 | } | |
6943f3da | 201 | EXPORT_SYMBOL(prom_searchsiblings); |
1da177e4 | 202 | |
1da177e4 | 203 | /* Interal version of nextprop that does not alter return values. */ |
1f42be48 | 204 | static char *__prom_nextprop(phandle node, char * oprop) |
1da177e4 LT |
205 | { |
206 | unsigned long flags; | |
207 | char *prop; | |
208 | ||
209 | spin_lock_irqsave(&prom_lock, flags); | |
210 | prop = prom_nodeops->no_nextprop(node, oprop); | |
211 | restore_current(); | |
212 | spin_unlock_irqrestore(&prom_lock, flags); | |
213 | ||
214 | return prop; | |
215 | } | |
216 | ||
1da177e4 LT |
217 | /* Return the property type string after property type 'oprop' |
218 | * at node 'node' . Returns empty string if no more | |
219 | * property types for this node. | |
220 | */ | |
8d125562 | 221 | char *prom_nextprop(phandle node, char *oprop, char *buffer) |
1da177e4 | 222 | { |
4a3a2552 | 223 | if (node == 0 || (s32)node == -1) |
1da177e4 LT |
224 | return ""; |
225 | ||
226 | return __prom_nextprop(node, oprop); | |
227 | } | |
6943f3da | 228 | EXPORT_SYMBOL(prom_nextprop); |
1da177e4 | 229 | |
8d125562 | 230 | phandle prom_finddevice(char *name) |
1da177e4 LT |
231 | { |
232 | char nbuf[128]; | |
233 | char *s = name, *d; | |
8d125562 | 234 | phandle node = prom_root_node, node2; |
1da177e4 LT |
235 | unsigned int which_io, phys_addr; |
236 | struct linux_prom_registers reg[PROMREG_MAX]; | |
237 | ||
238 | while (*s++) { | |
239 | if (!*s) return node; /* path '.../' is legal */ | |
240 | node = prom_getchild(node); | |
241 | ||
242 | for (d = nbuf; *s != 0 && *s != '@' && *s != '/';) | |
243 | *d++ = *s++; | |
244 | *d = 0; | |
245 | ||
246 | node = prom_searchsiblings(node, nbuf); | |
247 | if (!node) | |
248 | return 0; | |
249 | ||
250 | if (*s == '@') { | |
251 | if (isxdigit(s[1]) && s[2] == ',') { | |
252 | which_io = simple_strtoul(s+1, NULL, 16); | |
253 | phys_addr = simple_strtoul(s+3, &d, 16); | |
254 | if (d != s + 3 && (!*d || *d == '/') | |
255 | && d <= s + 3 + 8) { | |
256 | node2 = node; | |
4a3a2552 | 257 | while (node2 && (s32)node2 != -1) { |
1da177e4 LT |
258 | if (prom_getproperty (node2, "reg", (char *)reg, sizeof (reg)) > 0) { |
259 | if (which_io == reg[0].which_io && phys_addr == reg[0].phys_addr) { | |
260 | node = node2; | |
261 | break; | |
262 | } | |
263 | } | |
264 | node2 = prom_getsibling(node2); | |
4a3a2552 | 265 | if (!node2 || (s32)node2 == -1) |
1da177e4 LT |
266 | break; |
267 | node2 = prom_searchsiblings(prom_getsibling(node2), nbuf); | |
268 | } | |
269 | } | |
270 | } | |
271 | while (*s != 0 && *s != '/') s++; | |
272 | } | |
273 | } | |
274 | return node; | |
275 | } | |
6943f3da | 276 | EXPORT_SYMBOL(prom_finddevice); |
1da177e4 | 277 | |
1da177e4 LT |
278 | /* Set property 'pname' at node 'node' to value 'value' which has a length |
279 | * of 'size' bytes. Return the number of bytes the prom accepted. | |
280 | */ | |
8d125562 | 281 | int prom_setprop(phandle node, const char *pname, char *value, int size) |
1da177e4 LT |
282 | { |
283 | unsigned long flags; | |
284 | int ret; | |
285 | ||
5f66dd35 SR |
286 | if (size == 0) |
287 | return 0; | |
288 | if ((pname == NULL) || (value == NULL)) | |
289 | return 0; | |
1da177e4 LT |
290 | spin_lock_irqsave(&prom_lock, flags); |
291 | ret = prom_nodeops->no_setprop(node, pname, value, size); | |
292 | restore_current(); | |
293 | spin_unlock_irqrestore(&prom_lock, flags); | |
294 | return ret; | |
295 | } | |
6943f3da | 296 | EXPORT_SYMBOL(prom_setprop); |
1da177e4 | 297 | |
8d125562 | 298 | phandle prom_inst2pkg(int inst) |
1da177e4 | 299 | { |
8d125562 | 300 | phandle node; |
1da177e4 LT |
301 | unsigned long flags; |
302 | ||
303 | spin_lock_irqsave(&prom_lock, flags); | |
304 | node = (*romvec->pv_v2devops.v2_inst2pkg)(inst); | |
305 | restore_current(); | |
306 | spin_unlock_irqrestore(&prom_lock, flags); | |
4a3a2552 AS |
307 | if ((s32)node == -1) |
308 | return 0; | |
1da177e4 LT |
309 | return node; |
310 | } |