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e169cfbe GL |
1 | /* |
2 | * Functions for working with the Flattened Device Tree data format | |
3 | * | |
4 | * Copyright 2009 Benjamin Herrenschmidt, IBM Corp | |
5 | * benh@kernel.crashing.org | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or | |
8 | * modify it under the terms of the GNU General Public License | |
9 | * version 2 as published by the Free Software Foundation. | |
10 | */ | |
11 | ||
41f88009 | 12 | #include <linux/kernel.h> |
f7b3a835 | 13 | #include <linux/initrd.h> |
e169cfbe GL |
14 | #include <linux/of.h> |
15 | #include <linux/of_fdt.h> | |
4ef7b373 JK |
16 | #include <linux/string.h> |
17 | #include <linux/errno.h> | |
51975db0 | 18 | |
86e03221 GL |
19 | #ifdef CONFIG_PPC |
20 | #include <asm/machdep.h> | |
21 | #endif /* CONFIG_PPC */ | |
22 | ||
4ef7b373 JK |
23 | #include <asm/page.h> |
24 | ||
9706a36e SN |
25 | char *of_fdt_get_string(struct boot_param_header *blob, u32 offset) |
26 | { | |
27 | return ((char *)blob) + | |
28 | be32_to_cpu(blob->off_dt_strings) + offset; | |
29 | } | |
30 | ||
31 | /** | |
32 | * of_fdt_get_property - Given a node in the given flat blob, return | |
33 | * the property ptr | |
34 | */ | |
35 | void *of_fdt_get_property(struct boot_param_header *blob, | |
36 | unsigned long node, const char *name, | |
37 | unsigned long *size) | |
38 | { | |
39 | unsigned long p = node; | |
40 | ||
41 | do { | |
42 | u32 tag = be32_to_cpup((__be32 *)p); | |
43 | u32 sz, noff; | |
44 | const char *nstr; | |
45 | ||
46 | p += 4; | |
47 | if (tag == OF_DT_NOP) | |
48 | continue; | |
49 | if (tag != OF_DT_PROP) | |
50 | return NULL; | |
51 | ||
52 | sz = be32_to_cpup((__be32 *)p); | |
53 | noff = be32_to_cpup((__be32 *)(p + 4)); | |
54 | p += 8; | |
55 | if (be32_to_cpu(blob->version) < 0x10) | |
56 | p = ALIGN(p, sz >= 8 ? 8 : 4); | |
57 | ||
58 | nstr = of_fdt_get_string(blob, noff); | |
59 | if (nstr == NULL) { | |
60 | pr_warning("Can't find property index name !\n"); | |
61 | return NULL; | |
62 | } | |
63 | if (strcmp(name, nstr) == 0) { | |
64 | if (size) | |
65 | *size = sz; | |
66 | return (void *)p; | |
67 | } | |
68 | p += sz; | |
69 | p = ALIGN(p, 4); | |
70 | } while (1); | |
71 | } | |
72 | ||
73 | /** | |
74 | * of_fdt_is_compatible - Return true if given node from the given blob has | |
75 | * compat in its compatible list | |
76 | * @blob: A device tree blob | |
77 | * @node: node to test | |
78 | * @compat: compatible string to compare with compatible list. | |
79 | */ | |
80 | int of_fdt_is_compatible(struct boot_param_header *blob, | |
81 | unsigned long node, const char *compat) | |
82 | { | |
83 | const char *cp; | |
84 | unsigned long cplen, l; | |
85 | ||
86 | cp = of_fdt_get_property(blob, node, "compatible", &cplen); | |
87 | if (cp == NULL) | |
88 | return 0; | |
89 | while (cplen > 0) { | |
90 | if (of_compat_cmp(cp, compat, strlen(compat)) == 0) | |
91 | return 1; | |
92 | l = strlen(cp) + 1; | |
93 | cp += l; | |
94 | cplen -= l; | |
95 | } | |
96 | ||
97 | return 0; | |
98 | } | |
99 | ||
a40d6c4c | 100 | static void *unflatten_dt_alloc(unsigned long *mem, unsigned long size, |
bbd33931 GL |
101 | unsigned long align) |
102 | { | |
103 | void *res; | |
104 | ||
f1d4c3a7 | 105 | *mem = ALIGN(*mem, align); |
bbd33931 GL |
106 | res = (void *)*mem; |
107 | *mem += size; | |
108 | ||
109 | return res; | |
110 | } | |
111 | ||
112 | /** | |
113 | * unflatten_dt_node - Alloc and populate a device_node from the flat tree | |
a40d6c4c | 114 | * @blob: The parent device tree blob |
bbd33931 GL |
115 | * @p: pointer to node in flat tree |
116 | * @dad: Parent struct device_node | |
117 | * @allnextpp: pointer to ->allnext from last allocated device_node | |
118 | * @fpsize: Size of the node path up at the current depth. | |
119 | */ | |
a40d6c4c SN |
120 | unsigned long unflatten_dt_node(struct boot_param_header *blob, |
121 | unsigned long mem, | |
122 | unsigned long *p, | |
123 | struct device_node *dad, | |
124 | struct device_node ***allnextpp, | |
125 | unsigned long fpsize) | |
bbd33931 GL |
126 | { |
127 | struct device_node *np; | |
128 | struct property *pp, **prev_pp = NULL; | |
129 | char *pathp; | |
130 | u32 tag; | |
131 | unsigned int l, allocl; | |
132 | int has_name = 0; | |
133 | int new_format = 0; | |
134 | ||
33714881 | 135 | tag = be32_to_cpup((__be32 *)(*p)); |
bbd33931 GL |
136 | if (tag != OF_DT_BEGIN_NODE) { |
137 | pr_err("Weird tag at start of node: %x\n", tag); | |
138 | return mem; | |
139 | } | |
140 | *p += 4; | |
141 | pathp = (char *)*p; | |
142 | l = allocl = strlen(pathp) + 1; | |
f1d4c3a7 | 143 | *p = ALIGN(*p + l, 4); |
bbd33931 GL |
144 | |
145 | /* version 0x10 has a more compact unit name here instead of the full | |
146 | * path. we accumulate the full path size using "fpsize", we'll rebuild | |
147 | * it later. We detect this because the first character of the name is | |
148 | * not '/'. | |
149 | */ | |
150 | if ((*pathp) != '/') { | |
151 | new_format = 1; | |
152 | if (fpsize == 0) { | |
153 | /* root node: special case. fpsize accounts for path | |
154 | * plus terminating zero. root node only has '/', so | |
155 | * fpsize should be 2, but we want to avoid the first | |
156 | * level nodes to have two '/' so we use fpsize 1 here | |
157 | */ | |
158 | fpsize = 1; | |
159 | allocl = 2; | |
160 | } else { | |
161 | /* account for '/' and path size minus terminal 0 | |
162 | * already in 'l' | |
163 | */ | |
164 | fpsize += l; | |
165 | allocl = fpsize; | |
166 | } | |
167 | } | |
168 | ||
169 | np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl, | |
170 | __alignof__(struct device_node)); | |
171 | if (allnextpp) { | |
172 | memset(np, 0, sizeof(*np)); | |
173 | np->full_name = ((char *)np) + sizeof(struct device_node); | |
174 | if (new_format) { | |
175 | char *fn = np->full_name; | |
176 | /* rebuild full path for new format */ | |
177 | if (dad && dad->parent) { | |
178 | strcpy(fn, dad->full_name); | |
179 | #ifdef DEBUG | |
180 | if ((strlen(fn) + l + 1) != allocl) { | |
181 | pr_debug("%s: p: %d, l: %d, a: %d\n", | |
182 | pathp, (int)strlen(fn), | |
183 | l, allocl); | |
184 | } | |
185 | #endif | |
186 | fn += strlen(fn); | |
187 | } | |
188 | *(fn++) = '/'; | |
189 | memcpy(fn, pathp, l); | |
190 | } else | |
191 | memcpy(np->full_name, pathp, l); | |
192 | prev_pp = &np->properties; | |
193 | **allnextpp = np; | |
194 | *allnextpp = &np->allnext; | |
195 | if (dad != NULL) { | |
196 | np->parent = dad; | |
197 | /* we temporarily use the next field as `last_child'*/ | |
198 | if (dad->next == NULL) | |
199 | dad->child = np; | |
200 | else | |
201 | dad->next->sibling = np; | |
202 | dad->next = np; | |
203 | } | |
204 | kref_init(&np->kref); | |
205 | } | |
206 | while (1) { | |
207 | u32 sz, noff; | |
208 | char *pname; | |
209 | ||
33714881 | 210 | tag = be32_to_cpup((__be32 *)(*p)); |
bbd33931 GL |
211 | if (tag == OF_DT_NOP) { |
212 | *p += 4; | |
213 | continue; | |
214 | } | |
215 | if (tag != OF_DT_PROP) | |
216 | break; | |
217 | *p += 4; | |
33714881 JK |
218 | sz = be32_to_cpup((__be32 *)(*p)); |
219 | noff = be32_to_cpup((__be32 *)((*p) + 4)); | |
bbd33931 | 220 | *p += 8; |
a40d6c4c | 221 | if (be32_to_cpu(blob->version) < 0x10) |
f1d4c3a7 | 222 | *p = ALIGN(*p, sz >= 8 ? 8 : 4); |
bbd33931 | 223 | |
a40d6c4c | 224 | pname = of_fdt_get_string(blob, noff); |
bbd33931 GL |
225 | if (pname == NULL) { |
226 | pr_info("Can't find property name in list !\n"); | |
227 | break; | |
228 | } | |
229 | if (strcmp(pname, "name") == 0) | |
230 | has_name = 1; | |
231 | l = strlen(pname) + 1; | |
232 | pp = unflatten_dt_alloc(&mem, sizeof(struct property), | |
233 | __alignof__(struct property)); | |
234 | if (allnextpp) { | |
04b954a6 DG |
235 | /* We accept flattened tree phandles either in |
236 | * ePAPR-style "phandle" properties, or the | |
237 | * legacy "linux,phandle" properties. If both | |
238 | * appear and have different values, things | |
239 | * will get weird. Don't do that. */ | |
240 | if ((strcmp(pname, "phandle") == 0) || | |
241 | (strcmp(pname, "linux,phandle") == 0)) { | |
6016a363 | 242 | if (np->phandle == 0) |
9a6b2e58 | 243 | np->phandle = be32_to_cpup((__be32*)*p); |
bbd33931 | 244 | } |
04b954a6 DG |
245 | /* And we process the "ibm,phandle" property |
246 | * used in pSeries dynamic device tree | |
247 | * stuff */ | |
bbd33931 | 248 | if (strcmp(pname, "ibm,phandle") == 0) |
9a6b2e58 | 249 | np->phandle = be32_to_cpup((__be32 *)*p); |
bbd33931 GL |
250 | pp->name = pname; |
251 | pp->length = sz; | |
252 | pp->value = (void *)*p; | |
253 | *prev_pp = pp; | |
254 | prev_pp = &pp->next; | |
255 | } | |
f1d4c3a7 | 256 | *p = ALIGN((*p) + sz, 4); |
bbd33931 GL |
257 | } |
258 | /* with version 0x10 we may not have the name property, recreate | |
259 | * it here from the unit name if absent | |
260 | */ | |
261 | if (!has_name) { | |
262 | char *p1 = pathp, *ps = pathp, *pa = NULL; | |
263 | int sz; | |
264 | ||
265 | while (*p1) { | |
266 | if ((*p1) == '@') | |
267 | pa = p1; | |
268 | if ((*p1) == '/') | |
269 | ps = p1 + 1; | |
270 | p1++; | |
271 | } | |
272 | if (pa < ps) | |
273 | pa = p1; | |
274 | sz = (pa - ps) + 1; | |
275 | pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz, | |
276 | __alignof__(struct property)); | |
277 | if (allnextpp) { | |
278 | pp->name = "name"; | |
279 | pp->length = sz; | |
280 | pp->value = pp + 1; | |
281 | *prev_pp = pp; | |
282 | prev_pp = &pp->next; | |
283 | memcpy(pp->value, ps, sz - 1); | |
284 | ((char *)pp->value)[sz - 1] = 0; | |
285 | pr_debug("fixed up name for %s -> %s\n", pathp, | |
286 | (char *)pp->value); | |
287 | } | |
288 | } | |
289 | if (allnextpp) { | |
290 | *prev_pp = NULL; | |
291 | np->name = of_get_property(np, "name", NULL); | |
292 | np->type = of_get_property(np, "device_type", NULL); | |
293 | ||
294 | if (!np->name) | |
295 | np->name = "<NULL>"; | |
296 | if (!np->type) | |
297 | np->type = "<NULL>"; | |
298 | } | |
7f809e1f JG |
299 | while (tag == OF_DT_BEGIN_NODE || tag == OF_DT_NOP) { |
300 | if (tag == OF_DT_NOP) | |
301 | *p += 4; | |
302 | else | |
a40d6c4c SN |
303 | mem = unflatten_dt_node(blob, mem, p, np, allnextpp, |
304 | fpsize); | |
33714881 | 305 | tag = be32_to_cpup((__be32 *)(*p)); |
bbd33931 GL |
306 | } |
307 | if (tag != OF_DT_END_NODE) { | |
308 | pr_err("Weird tag at end of node: %x\n", tag); | |
309 | return mem; | |
310 | } | |
311 | *p += 4; | |
312 | return mem; | |
313 | } | |
41f88009 | 314 | |
57d00ecf SN |
315 | /* Everything below here references initial_boot_params directly. */ |
316 | int __initdata dt_root_addr_cells; | |
317 | int __initdata dt_root_size_cells; | |
318 | ||
319 | struct boot_param_header *initial_boot_params; | |
320 | ||
321 | #ifdef CONFIG_OF_EARLY_FLATTREE | |
322 | ||
323 | /** | |
324 | * of_scan_flat_dt - scan flattened tree blob and call callback on each. | |
325 | * @it: callback function | |
326 | * @data: context data pointer | |
327 | * | |
328 | * This function is used to scan the flattened device-tree, it is | |
329 | * used to extract the memory information at boot before we can | |
330 | * unflatten the tree | |
331 | */ | |
332 | int __init of_scan_flat_dt(int (*it)(unsigned long node, | |
333 | const char *uname, int depth, | |
334 | void *data), | |
335 | void *data) | |
336 | { | |
337 | unsigned long p = ((unsigned long)initial_boot_params) + | |
338 | be32_to_cpu(initial_boot_params->off_dt_struct); | |
339 | int rc = 0; | |
340 | int depth = -1; | |
341 | ||
342 | do { | |
343 | u32 tag = be32_to_cpup((__be32 *)p); | |
344 | char *pathp; | |
345 | ||
346 | p += 4; | |
347 | if (tag == OF_DT_END_NODE) { | |
348 | depth--; | |
349 | continue; | |
350 | } | |
351 | if (tag == OF_DT_NOP) | |
352 | continue; | |
353 | if (tag == OF_DT_END) | |
354 | break; | |
355 | if (tag == OF_DT_PROP) { | |
356 | u32 sz = be32_to_cpup((__be32 *)p); | |
357 | p += 8; | |
358 | if (be32_to_cpu(initial_boot_params->version) < 0x10) | |
359 | p = ALIGN(p, sz >= 8 ? 8 : 4); | |
360 | p += sz; | |
361 | p = ALIGN(p, 4); | |
362 | continue; | |
363 | } | |
364 | if (tag != OF_DT_BEGIN_NODE) { | |
365 | pr_err("Invalid tag %x in flat device tree!\n", tag); | |
366 | return -EINVAL; | |
367 | } | |
368 | depth++; | |
369 | pathp = (char *)p; | |
370 | p = ALIGN(p + strlen(pathp) + 1, 4); | |
371 | if ((*pathp) == '/') { | |
372 | char *lp, *np; | |
373 | for (lp = NULL, np = pathp; *np; np++) | |
374 | if ((*np) == '/') | |
375 | lp = np+1; | |
376 | if (lp != NULL) | |
377 | pathp = lp; | |
378 | } | |
379 | rc = it(p, pathp, depth, data); | |
380 | if (rc != 0) | |
381 | break; | |
382 | } while (1); | |
383 | ||
384 | return rc; | |
385 | } | |
386 | ||
387 | /** | |
388 | * of_get_flat_dt_root - find the root node in the flat blob | |
389 | */ | |
390 | unsigned long __init of_get_flat_dt_root(void) | |
391 | { | |
392 | unsigned long p = ((unsigned long)initial_boot_params) + | |
393 | be32_to_cpu(initial_boot_params->off_dt_struct); | |
394 | ||
395 | while (be32_to_cpup((__be32 *)p) == OF_DT_NOP) | |
396 | p += 4; | |
397 | BUG_ON(be32_to_cpup((__be32 *)p) != OF_DT_BEGIN_NODE); | |
398 | p += 4; | |
399 | return ALIGN(p + strlen((char *)p) + 1, 4); | |
400 | } | |
401 | ||
402 | /** | |
403 | * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr | |
404 | * | |
405 | * This function can be used within scan_flattened_dt callback to get | |
406 | * access to properties | |
407 | */ | |
408 | void *__init of_get_flat_dt_prop(unsigned long node, const char *name, | |
409 | unsigned long *size) | |
410 | { | |
411 | return of_fdt_get_property(initial_boot_params, node, name, size); | |
412 | } | |
413 | ||
414 | /** | |
415 | * of_flat_dt_is_compatible - Return true if given node has compat in compatible list | |
416 | * @node: node to test | |
417 | * @compat: compatible string to compare with compatible list. | |
418 | */ | |
419 | int __init of_flat_dt_is_compatible(unsigned long node, const char *compat) | |
420 | { | |
421 | return of_fdt_is_compatible(initial_boot_params, node, compat); | |
422 | } | |
423 | ||
f7b3a835 GL |
424 | #ifdef CONFIG_BLK_DEV_INITRD |
425 | /** | |
426 | * early_init_dt_check_for_initrd - Decode initrd location from flat tree | |
427 | * @node: reference to node containing initrd location ('chosen') | |
428 | */ | |
429 | void __init early_init_dt_check_for_initrd(unsigned long node) | |
430 | { | |
1406bc2f | 431 | unsigned long start, end, len; |
33714881 | 432 | __be32 *prop; |
f7b3a835 GL |
433 | |
434 | pr_debug("Looking for initrd properties... "); | |
435 | ||
436 | prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len); | |
1406bc2f JK |
437 | if (!prop) |
438 | return; | |
439 | start = of_read_ulong(prop, len/4); | |
440 | ||
441 | prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len); | |
442 | if (!prop) | |
443 | return; | |
444 | end = of_read_ulong(prop, len/4); | |
f7b3a835 | 445 | |
1406bc2f JK |
446 | early_init_dt_setup_initrd_arch(start, end); |
447 | pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n", start, end); | |
f7b3a835 GL |
448 | } |
449 | #else | |
450 | inline void early_init_dt_check_for_initrd(unsigned long node) | |
451 | { | |
452 | } | |
453 | #endif /* CONFIG_BLK_DEV_INITRD */ | |
454 | ||
f00abd94 GL |
455 | /** |
456 | * early_init_dt_scan_root - fetch the top level address and size cells | |
457 | */ | |
458 | int __init early_init_dt_scan_root(unsigned long node, const char *uname, | |
459 | int depth, void *data) | |
460 | { | |
33714881 | 461 | __be32 *prop; |
f00abd94 GL |
462 | |
463 | if (depth != 0) | |
464 | return 0; | |
465 | ||
33714881 JK |
466 | dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT; |
467 | dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT; | |
468 | ||
f00abd94 | 469 | prop = of_get_flat_dt_prop(node, "#size-cells", NULL); |
33714881 JK |
470 | if (prop) |
471 | dt_root_size_cells = be32_to_cpup(prop); | |
f00abd94 GL |
472 | pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells); |
473 | ||
474 | prop = of_get_flat_dt_prop(node, "#address-cells", NULL); | |
33714881 JK |
475 | if (prop) |
476 | dt_root_addr_cells = be32_to_cpup(prop); | |
f00abd94 GL |
477 | pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells); |
478 | ||
479 | /* break now */ | |
480 | return 1; | |
481 | } | |
482 | ||
2e89e685 | 483 | u64 __init dt_mem_next_cell(int s, __be32 **cellp) |
83f7a06e | 484 | { |
2e89e685 | 485 | __be32 *p = *cellp; |
83f7a06e GL |
486 | |
487 | *cellp = p + s; | |
488 | return of_read_number(p, s); | |
489 | } | |
490 | ||
51975db0 GL |
491 | /** |
492 | * early_init_dt_scan_memory - Look for an parse memory nodes | |
493 | */ | |
494 | int __init early_init_dt_scan_memory(unsigned long node, const char *uname, | |
495 | int depth, void *data) | |
496 | { | |
497 | char *type = of_get_flat_dt_prop(node, "device_type", NULL); | |
498 | __be32 *reg, *endp; | |
499 | unsigned long l; | |
500 | ||
501 | /* We are scanning "memory" nodes only */ | |
502 | if (type == NULL) { | |
503 | /* | |
504 | * The longtrail doesn't have a device_type on the | |
505 | * /memory node, so look for the node called /memory@0. | |
506 | */ | |
507 | if (depth != 1 || strcmp(uname, "memory@0") != 0) | |
508 | return 0; | |
509 | } else if (strcmp(type, "memory") != 0) | |
510 | return 0; | |
511 | ||
512 | reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l); | |
513 | if (reg == NULL) | |
514 | reg = of_get_flat_dt_prop(node, "reg", &l); | |
515 | if (reg == NULL) | |
516 | return 0; | |
517 | ||
518 | endp = reg + (l / sizeof(__be32)); | |
519 | ||
520 | pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n", | |
521 | uname, l, reg[0], reg[1], reg[2], reg[3]); | |
522 | ||
523 | while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) { | |
524 | u64 base, size; | |
525 | ||
526 | base = dt_mem_next_cell(dt_root_addr_cells, ®); | |
527 | size = dt_mem_next_cell(dt_root_size_cells, ®); | |
528 | ||
529 | if (size == 0) | |
530 | continue; | |
531 | pr_debug(" - %llx , %llx\n", (unsigned long long)base, | |
532 | (unsigned long long)size); | |
533 | ||
534 | early_init_dt_add_memory_arch(base, size); | |
535 | } | |
536 | ||
537 | return 0; | |
538 | } | |
539 | ||
86e03221 GL |
540 | int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, |
541 | int depth, void *data) | |
542 | { | |
543 | unsigned long l; | |
544 | char *p; | |
545 | ||
546 | pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname); | |
547 | ||
548 | if (depth != 1 || | |
549 | (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0)) | |
550 | return 0; | |
551 | ||
552 | early_init_dt_check_for_initrd(node); | |
553 | ||
554 | /* Retreive command line */ | |
555 | p = of_get_flat_dt_prop(node, "bootargs", &l); | |
556 | if (p != NULL && l > 0) | |
557 | strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE)); | |
558 | ||
559 | #ifdef CONFIG_CMDLINE | |
560 | #ifndef CONFIG_CMDLINE_FORCE | |
561 | if (p == NULL || l == 0 || (l == 1 && (*p) == 0)) | |
562 | #endif | |
563 | strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE); | |
564 | #endif /* CONFIG_CMDLINE */ | |
565 | ||
86e03221 GL |
566 | pr_debug("Command line is: %s\n", cmd_line); |
567 | ||
568 | /* break now */ | |
569 | return 1; | |
570 | } | |
571 | ||
41f88009 GL |
572 | /** |
573 | * unflatten_device_tree - create tree of device_nodes from flat blob | |
574 | * | |
575 | * unflattens the device-tree passed by the firmware, creating the | |
576 | * tree of struct device_node. It also fills the "name" and "type" | |
577 | * pointers of the nodes so the normal device-tree walking functions | |
578 | * can be used. | |
579 | */ | |
580 | void __init unflatten_device_tree(void) | |
581 | { | |
582 | unsigned long start, mem, size; | |
583 | struct device_node **allnextp = &allnodes; | |
584 | ||
585 | pr_debug(" -> unflatten_device_tree()\n"); | |
586 | ||
8bfe9b5c GL |
587 | if (!initial_boot_params) { |
588 | pr_debug("No device tree pointer\n"); | |
589 | return; | |
590 | } | |
591 | ||
592 | pr_debug("Unflattening device tree:\n"); | |
593 | pr_debug("magic: %08x\n", be32_to_cpu(initial_boot_params->magic)); | |
594 | pr_debug("size: %08x\n", be32_to_cpu(initial_boot_params->totalsize)); | |
595 | pr_debug("version: %08x\n", be32_to_cpu(initial_boot_params->version)); | |
596 | ||
597 | if (be32_to_cpu(initial_boot_params->magic) != OF_DT_HEADER) { | |
598 | pr_err("Invalid device tree blob header\n"); | |
599 | return; | |
600 | } | |
601 | ||
41f88009 GL |
602 | /* First pass, scan for size */ |
603 | start = ((unsigned long)initial_boot_params) + | |
087f79c4 | 604 | be32_to_cpu(initial_boot_params->off_dt_struct); |
a40d6c4c SN |
605 | size = unflatten_dt_node(initial_boot_params, 0, &start, |
606 | NULL, NULL, 0); | |
41f88009 GL |
607 | size = (size | 3) + 1; |
608 | ||
609 | pr_debug(" size is %lx, allocating...\n", size); | |
610 | ||
611 | /* Allocate memory for the expanded device tree */ | |
4ef7b373 JK |
612 | mem = early_init_dt_alloc_memory_arch(size + 4, |
613 | __alignof__(struct device_node)); | |
41f88009 GL |
614 | mem = (unsigned long) __va(mem); |
615 | ||
33714881 | 616 | ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef); |
41f88009 GL |
617 | |
618 | pr_debug(" unflattening %lx...\n", mem); | |
619 | ||
620 | /* Second pass, do actual unflattening */ | |
621 | start = ((unsigned long)initial_boot_params) + | |
087f79c4 | 622 | be32_to_cpu(initial_boot_params->off_dt_struct); |
a40d6c4c SN |
623 | unflatten_dt_node(initial_boot_params, mem, &start, |
624 | NULL, &allnextp, 0); | |
33714881 | 625 | if (be32_to_cpup((__be32 *)start) != OF_DT_END) |
41f88009 | 626 | pr_warning("Weird tag at end of tree: %08x\n", *((u32 *)start)); |
33714881 | 627 | if (be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeef) |
41f88009 | 628 | pr_warning("End of tree marker overwritten: %08x\n", |
33714881 | 629 | be32_to_cpu(((__be32 *)mem)[size / 4])); |
41f88009 GL |
630 | *allnextp = NULL; |
631 | ||
632 | /* Get pointer to OF "/chosen" node for use everywhere */ | |
633 | of_chosen = of_find_node_by_path("/chosen"); | |
634 | if (of_chosen == NULL) | |
635 | of_chosen = of_find_node_by_path("/chosen@0"); | |
636 | ||
637 | pr_debug(" <- unflatten_device_tree()\n"); | |
638 | } | |
e6ce1324 SN |
639 | |
640 | #endif /* CONFIG_OF_EARLY_FLATTREE */ |