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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> |
a1727da5 | 14 | #include <linux/memblock.h> |
fe140423 | 15 | #include <linux/module.h> |
e169cfbe GL |
16 | #include <linux/of.h> |
17 | #include <linux/of_fdt.h> | |
4ef7b373 JK |
18 | #include <linux/string.h> |
19 | #include <linux/errno.h> | |
fe140423 | 20 | #include <linux/slab.h> |
109b6236 | 21 | #include <linux/random.h> |
51975db0 | 22 | |
c89810ac | 23 | #include <asm/setup.h> /* for COMMAND_LINE_SIZE */ |
86e03221 GL |
24 | #ifdef CONFIG_PPC |
25 | #include <asm/machdep.h> | |
26 | #endif /* CONFIG_PPC */ | |
27 | ||
4ef7b373 JK |
28 | #include <asm/page.h> |
29 | ||
9706a36e SN |
30 | char *of_fdt_get_string(struct boot_param_header *blob, u32 offset) |
31 | { | |
32 | return ((char *)blob) + | |
33 | be32_to_cpu(blob->off_dt_strings) + offset; | |
34 | } | |
35 | ||
36 | /** | |
37 | * of_fdt_get_property - Given a node in the given flat blob, return | |
38 | * the property ptr | |
39 | */ | |
40 | void *of_fdt_get_property(struct boot_param_header *blob, | |
41 | unsigned long node, const char *name, | |
42 | unsigned long *size) | |
43 | { | |
44 | unsigned long p = node; | |
45 | ||
46 | do { | |
47 | u32 tag = be32_to_cpup((__be32 *)p); | |
48 | u32 sz, noff; | |
49 | const char *nstr; | |
50 | ||
51 | p += 4; | |
52 | if (tag == OF_DT_NOP) | |
53 | continue; | |
54 | if (tag != OF_DT_PROP) | |
55 | return NULL; | |
56 | ||
57 | sz = be32_to_cpup((__be32 *)p); | |
58 | noff = be32_to_cpup((__be32 *)(p + 4)); | |
59 | p += 8; | |
60 | if (be32_to_cpu(blob->version) < 0x10) | |
61 | p = ALIGN(p, sz >= 8 ? 8 : 4); | |
62 | ||
63 | nstr = of_fdt_get_string(blob, noff); | |
64 | if (nstr == NULL) { | |
65 | pr_warning("Can't find property index name !\n"); | |
66 | return NULL; | |
67 | } | |
68 | if (strcmp(name, nstr) == 0) { | |
69 | if (size) | |
70 | *size = sz; | |
71 | return (void *)p; | |
72 | } | |
73 | p += sz; | |
74 | p = ALIGN(p, 4); | |
75 | } while (1); | |
76 | } | |
77 | ||
78 | /** | |
79 | * of_fdt_is_compatible - Return true if given node from the given blob has | |
80 | * compat in its compatible list | |
81 | * @blob: A device tree blob | |
82 | * @node: node to test | |
83 | * @compat: compatible string to compare with compatible list. | |
a4f740cf GL |
84 | * |
85 | * On match, returns a non-zero value with smaller values returned for more | |
86 | * specific compatible values. | |
9706a36e SN |
87 | */ |
88 | int of_fdt_is_compatible(struct boot_param_header *blob, | |
89 | unsigned long node, const char *compat) | |
90 | { | |
91 | const char *cp; | |
a4f740cf | 92 | unsigned long cplen, l, score = 0; |
9706a36e SN |
93 | |
94 | cp = of_fdt_get_property(blob, node, "compatible", &cplen); | |
95 | if (cp == NULL) | |
96 | return 0; | |
97 | while (cplen > 0) { | |
a4f740cf | 98 | score++; |
9706a36e | 99 | if (of_compat_cmp(cp, compat, strlen(compat)) == 0) |
a4f740cf | 100 | return score; |
9706a36e SN |
101 | l = strlen(cp) + 1; |
102 | cp += l; | |
103 | cplen -= l; | |
104 | } | |
105 | ||
106 | return 0; | |
107 | } | |
108 | ||
a4f740cf GL |
109 | /** |
110 | * of_fdt_match - Return true if node matches a list of compatible values | |
111 | */ | |
112 | int of_fdt_match(struct boot_param_header *blob, unsigned long node, | |
7b482c83 | 113 | const char *const *compat) |
a4f740cf GL |
114 | { |
115 | unsigned int tmp, score = 0; | |
116 | ||
117 | if (!compat) | |
118 | return 0; | |
119 | ||
120 | while (*compat) { | |
121 | tmp = of_fdt_is_compatible(blob, node, *compat); | |
122 | if (tmp && (score == 0 || (tmp < score))) | |
123 | score = tmp; | |
124 | compat++; | |
125 | } | |
126 | ||
127 | return score; | |
128 | } | |
129 | ||
44856819 | 130 | static void *unflatten_dt_alloc(void **mem, unsigned long size, |
bbd33931 GL |
131 | unsigned long align) |
132 | { | |
133 | void *res; | |
134 | ||
44856819 GL |
135 | *mem = PTR_ALIGN(*mem, align); |
136 | res = *mem; | |
bbd33931 GL |
137 | *mem += size; |
138 | ||
139 | return res; | |
140 | } | |
141 | ||
142 | /** | |
143 | * unflatten_dt_node - Alloc and populate a device_node from the flat tree | |
a40d6c4c | 144 | * @blob: The parent device tree blob |
a7006c97 | 145 | * @mem: Memory chunk to use for allocating device nodes and properties |
bbd33931 GL |
146 | * @p: pointer to node in flat tree |
147 | * @dad: Parent struct device_node | |
148 | * @allnextpp: pointer to ->allnext from last allocated device_node | |
149 | * @fpsize: Size of the node path up at the current depth. | |
150 | */ | |
44856819 GL |
151 | static void * unflatten_dt_node(struct boot_param_header *blob, |
152 | void *mem, | |
153 | void **p, | |
a40d6c4c SN |
154 | struct device_node *dad, |
155 | struct device_node ***allnextpp, | |
156 | unsigned long fpsize) | |
bbd33931 GL |
157 | { |
158 | struct device_node *np; | |
159 | struct property *pp, **prev_pp = NULL; | |
160 | char *pathp; | |
161 | u32 tag; | |
162 | unsigned int l, allocl; | |
163 | int has_name = 0; | |
164 | int new_format = 0; | |
165 | ||
44856819 | 166 | tag = be32_to_cpup(*p); |
bbd33931 GL |
167 | if (tag != OF_DT_BEGIN_NODE) { |
168 | pr_err("Weird tag at start of node: %x\n", tag); | |
169 | return mem; | |
170 | } | |
171 | *p += 4; | |
44856819 | 172 | pathp = *p; |
bbd33931 | 173 | l = allocl = strlen(pathp) + 1; |
44856819 | 174 | *p = PTR_ALIGN(*p + l, 4); |
bbd33931 GL |
175 | |
176 | /* version 0x10 has a more compact unit name here instead of the full | |
177 | * path. we accumulate the full path size using "fpsize", we'll rebuild | |
178 | * it later. We detect this because the first character of the name is | |
179 | * not '/'. | |
180 | */ | |
181 | if ((*pathp) != '/') { | |
182 | new_format = 1; | |
183 | if (fpsize == 0) { | |
184 | /* root node: special case. fpsize accounts for path | |
185 | * plus terminating zero. root node only has '/', so | |
186 | * fpsize should be 2, but we want to avoid the first | |
187 | * level nodes to have two '/' so we use fpsize 1 here | |
188 | */ | |
189 | fpsize = 1; | |
190 | allocl = 2; | |
0fca5dea CM |
191 | l = 1; |
192 | *pathp = '\0'; | |
bbd33931 GL |
193 | } else { |
194 | /* account for '/' and path size minus terminal 0 | |
195 | * already in 'l' | |
196 | */ | |
197 | fpsize += l; | |
198 | allocl = fpsize; | |
199 | } | |
200 | } | |
201 | ||
202 | np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl, | |
203 | __alignof__(struct device_node)); | |
204 | if (allnextpp) { | |
c22618a1 | 205 | char *fn; |
c22618a1 | 206 | np->full_name = fn = ((char *)np) + sizeof(*np); |
bbd33931 | 207 | if (new_format) { |
bbd33931 GL |
208 | /* rebuild full path for new format */ |
209 | if (dad && dad->parent) { | |
210 | strcpy(fn, dad->full_name); | |
211 | #ifdef DEBUG | |
212 | if ((strlen(fn) + l + 1) != allocl) { | |
213 | pr_debug("%s: p: %d, l: %d, a: %d\n", | |
214 | pathp, (int)strlen(fn), | |
215 | l, allocl); | |
216 | } | |
217 | #endif | |
218 | fn += strlen(fn); | |
219 | } | |
220 | *(fn++) = '/'; | |
c22618a1 GL |
221 | } |
222 | memcpy(fn, pathp, l); | |
223 | ||
bbd33931 GL |
224 | prev_pp = &np->properties; |
225 | **allnextpp = np; | |
226 | *allnextpp = &np->allnext; | |
227 | if (dad != NULL) { | |
228 | np->parent = dad; | |
229 | /* we temporarily use the next field as `last_child'*/ | |
230 | if (dad->next == NULL) | |
231 | dad->child = np; | |
232 | else | |
233 | dad->next->sibling = np; | |
234 | dad->next = np; | |
235 | } | |
236 | kref_init(&np->kref); | |
237 | } | |
a7006c97 | 238 | /* process properties */ |
bbd33931 GL |
239 | while (1) { |
240 | u32 sz, noff; | |
241 | char *pname; | |
242 | ||
44856819 | 243 | tag = be32_to_cpup(*p); |
bbd33931 GL |
244 | if (tag == OF_DT_NOP) { |
245 | *p += 4; | |
246 | continue; | |
247 | } | |
248 | if (tag != OF_DT_PROP) | |
249 | break; | |
250 | *p += 4; | |
44856819 GL |
251 | sz = be32_to_cpup(*p); |
252 | noff = be32_to_cpup(*p + 4); | |
bbd33931 | 253 | *p += 8; |
a40d6c4c | 254 | if (be32_to_cpu(blob->version) < 0x10) |
44856819 | 255 | *p = PTR_ALIGN(*p, sz >= 8 ? 8 : 4); |
bbd33931 | 256 | |
a40d6c4c | 257 | pname = of_fdt_get_string(blob, noff); |
bbd33931 GL |
258 | if (pname == NULL) { |
259 | pr_info("Can't find property name in list !\n"); | |
260 | break; | |
261 | } | |
262 | if (strcmp(pname, "name") == 0) | |
263 | has_name = 1; | |
264 | l = strlen(pname) + 1; | |
265 | pp = unflatten_dt_alloc(&mem, sizeof(struct property), | |
266 | __alignof__(struct property)); | |
267 | if (allnextpp) { | |
04b954a6 DG |
268 | /* We accept flattened tree phandles either in |
269 | * ePAPR-style "phandle" properties, or the | |
270 | * legacy "linux,phandle" properties. If both | |
271 | * appear and have different values, things | |
272 | * will get weird. Don't do that. */ | |
273 | if ((strcmp(pname, "phandle") == 0) || | |
274 | (strcmp(pname, "linux,phandle") == 0)) { | |
6016a363 | 275 | if (np->phandle == 0) |
9a6b2e58 | 276 | np->phandle = be32_to_cpup((__be32*)*p); |
bbd33931 | 277 | } |
04b954a6 DG |
278 | /* And we process the "ibm,phandle" property |
279 | * used in pSeries dynamic device tree | |
280 | * stuff */ | |
bbd33931 | 281 | if (strcmp(pname, "ibm,phandle") == 0) |
9a6b2e58 | 282 | np->phandle = be32_to_cpup((__be32 *)*p); |
bbd33931 GL |
283 | pp->name = pname; |
284 | pp->length = sz; | |
44856819 | 285 | pp->value = *p; |
bbd33931 GL |
286 | *prev_pp = pp; |
287 | prev_pp = &pp->next; | |
288 | } | |
44856819 | 289 | *p = PTR_ALIGN((*p) + sz, 4); |
bbd33931 GL |
290 | } |
291 | /* with version 0x10 we may not have the name property, recreate | |
292 | * it here from the unit name if absent | |
293 | */ | |
294 | if (!has_name) { | |
295 | char *p1 = pathp, *ps = pathp, *pa = NULL; | |
296 | int sz; | |
297 | ||
298 | while (*p1) { | |
299 | if ((*p1) == '@') | |
300 | pa = p1; | |
301 | if ((*p1) == '/') | |
302 | ps = p1 + 1; | |
303 | p1++; | |
304 | } | |
305 | if (pa < ps) | |
306 | pa = p1; | |
307 | sz = (pa - ps) + 1; | |
308 | pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz, | |
309 | __alignof__(struct property)); | |
310 | if (allnextpp) { | |
311 | pp->name = "name"; | |
312 | pp->length = sz; | |
313 | pp->value = pp + 1; | |
314 | *prev_pp = pp; | |
315 | prev_pp = &pp->next; | |
316 | memcpy(pp->value, ps, sz - 1); | |
317 | ((char *)pp->value)[sz - 1] = 0; | |
318 | pr_debug("fixed up name for %s -> %s\n", pathp, | |
319 | (char *)pp->value); | |
320 | } | |
321 | } | |
322 | if (allnextpp) { | |
323 | *prev_pp = NULL; | |
324 | np->name = of_get_property(np, "name", NULL); | |
325 | np->type = of_get_property(np, "device_type", NULL); | |
326 | ||
327 | if (!np->name) | |
328 | np->name = "<NULL>"; | |
329 | if (!np->type) | |
330 | np->type = "<NULL>"; | |
331 | } | |
7f809e1f JG |
332 | while (tag == OF_DT_BEGIN_NODE || tag == OF_DT_NOP) { |
333 | if (tag == OF_DT_NOP) | |
334 | *p += 4; | |
335 | else | |
a40d6c4c SN |
336 | mem = unflatten_dt_node(blob, mem, p, np, allnextpp, |
337 | fpsize); | |
44856819 | 338 | tag = be32_to_cpup(*p); |
bbd33931 GL |
339 | } |
340 | if (tag != OF_DT_END_NODE) { | |
341 | pr_err("Weird tag at end of node: %x\n", tag); | |
342 | return mem; | |
343 | } | |
344 | *p += 4; | |
345 | return mem; | |
346 | } | |
41f88009 | 347 | |
fe140423 SN |
348 | /** |
349 | * __unflatten_device_tree - create tree of device_nodes from flat blob | |
350 | * | |
351 | * unflattens a device-tree, creating the | |
352 | * tree of struct device_node. It also fills the "name" and "type" | |
353 | * pointers of the nodes so the normal device-tree walking functions | |
354 | * can be used. | |
355 | * @blob: The blob to expand | |
356 | * @mynodes: The device_node tree created by the call | |
357 | * @dt_alloc: An allocator that provides a virtual address to memory | |
358 | * for the resulting tree | |
359 | */ | |
a7006c97 | 360 | static void __unflatten_device_tree(struct boot_param_header *blob, |
fe140423 SN |
361 | struct device_node **mynodes, |
362 | void * (*dt_alloc)(u64 size, u64 align)) | |
363 | { | |
44856819 GL |
364 | unsigned long size; |
365 | void *start, *mem; | |
fe140423 SN |
366 | struct device_node **allnextp = mynodes; |
367 | ||
368 | pr_debug(" -> unflatten_device_tree()\n"); | |
369 | ||
370 | if (!blob) { | |
371 | pr_debug("No device tree pointer\n"); | |
372 | return; | |
373 | } | |
374 | ||
375 | pr_debug("Unflattening device tree:\n"); | |
376 | pr_debug("magic: %08x\n", be32_to_cpu(blob->magic)); | |
377 | pr_debug("size: %08x\n", be32_to_cpu(blob->totalsize)); | |
378 | pr_debug("version: %08x\n", be32_to_cpu(blob->version)); | |
379 | ||
380 | if (be32_to_cpu(blob->magic) != OF_DT_HEADER) { | |
381 | pr_err("Invalid device tree blob header\n"); | |
382 | return; | |
383 | } | |
384 | ||
385 | /* First pass, scan for size */ | |
44856819 GL |
386 | start = ((void *)blob) + be32_to_cpu(blob->off_dt_struct); |
387 | size = (unsigned long)unflatten_dt_node(blob, 0, &start, NULL, NULL, 0); | |
388 | size = ALIGN(size, 4); | |
fe140423 SN |
389 | |
390 | pr_debug(" size is %lx, allocating...\n", size); | |
391 | ||
392 | /* Allocate memory for the expanded device tree */ | |
44856819 GL |
393 | mem = dt_alloc(size + 4, __alignof__(struct device_node)); |
394 | memset(mem, 0, size); | |
fe140423 | 395 | |
44856819 | 396 | *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef); |
9e401275 | 397 | |
44856819 | 398 | pr_debug(" unflattening %p...\n", mem); |
fe140423 SN |
399 | |
400 | /* Second pass, do actual unflattening */ | |
44856819 | 401 | start = ((void *)blob) + be32_to_cpu(blob->off_dt_struct); |
fe140423 | 402 | unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0); |
44856819 GL |
403 | if (be32_to_cpup(start) != OF_DT_END) |
404 | pr_warning("Weird tag at end of tree: %08x\n", be32_to_cpup(start)); | |
405 | if (be32_to_cpup(mem + size) != 0xdeadbeef) | |
fe140423 | 406 | pr_warning("End of tree marker overwritten: %08x\n", |
44856819 | 407 | be32_to_cpup(mem + size)); |
fe140423 SN |
408 | *allnextp = NULL; |
409 | ||
410 | pr_debug(" <- unflatten_device_tree()\n"); | |
411 | } | |
412 | ||
413 | static void *kernel_tree_alloc(u64 size, u64 align) | |
414 | { | |
415 | return kzalloc(size, GFP_KERNEL); | |
416 | } | |
417 | ||
418 | /** | |
419 | * of_fdt_unflatten_tree - create tree of device_nodes from flat blob | |
420 | * | |
421 | * unflattens the device-tree passed by the firmware, creating the | |
422 | * tree of struct device_node. It also fills the "name" and "type" | |
423 | * pointers of the nodes so the normal device-tree walking functions | |
424 | * can be used. | |
425 | */ | |
426 | void of_fdt_unflatten_tree(unsigned long *blob, | |
427 | struct device_node **mynodes) | |
428 | { | |
429 | struct boot_param_header *device_tree = | |
430 | (struct boot_param_header *)blob; | |
431 | __unflatten_device_tree(device_tree, mynodes, &kernel_tree_alloc); | |
432 | } | |
433 | EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree); | |
434 | ||
57d00ecf SN |
435 | /* Everything below here references initial_boot_params directly. */ |
436 | int __initdata dt_root_addr_cells; | |
437 | int __initdata dt_root_size_cells; | |
438 | ||
439 | struct boot_param_header *initial_boot_params; | |
440 | ||
441 | #ifdef CONFIG_OF_EARLY_FLATTREE | |
442 | ||
443 | /** | |
444 | * of_scan_flat_dt - scan flattened tree blob and call callback on each. | |
445 | * @it: callback function | |
446 | * @data: context data pointer | |
447 | * | |
448 | * This function is used to scan the flattened device-tree, it is | |
449 | * used to extract the memory information at boot before we can | |
450 | * unflatten the tree | |
451 | */ | |
452 | int __init of_scan_flat_dt(int (*it)(unsigned long node, | |
453 | const char *uname, int depth, | |
454 | void *data), | |
455 | void *data) | |
456 | { | |
457 | unsigned long p = ((unsigned long)initial_boot_params) + | |
458 | be32_to_cpu(initial_boot_params->off_dt_struct); | |
459 | int rc = 0; | |
460 | int depth = -1; | |
461 | ||
462 | do { | |
463 | u32 tag = be32_to_cpup((__be32 *)p); | |
e55b0829 | 464 | const char *pathp; |
57d00ecf SN |
465 | |
466 | p += 4; | |
467 | if (tag == OF_DT_END_NODE) { | |
468 | depth--; | |
469 | continue; | |
470 | } | |
471 | if (tag == OF_DT_NOP) | |
472 | continue; | |
473 | if (tag == OF_DT_END) | |
474 | break; | |
475 | if (tag == OF_DT_PROP) { | |
476 | u32 sz = be32_to_cpup((__be32 *)p); | |
477 | p += 8; | |
478 | if (be32_to_cpu(initial_boot_params->version) < 0x10) | |
479 | p = ALIGN(p, sz >= 8 ? 8 : 4); | |
480 | p += sz; | |
481 | p = ALIGN(p, 4); | |
482 | continue; | |
483 | } | |
484 | if (tag != OF_DT_BEGIN_NODE) { | |
485 | pr_err("Invalid tag %x in flat device tree!\n", tag); | |
486 | return -EINVAL; | |
487 | } | |
488 | depth++; | |
489 | pathp = (char *)p; | |
490 | p = ALIGN(p + strlen(pathp) + 1, 4); | |
375da3a7 AS |
491 | if (*pathp == '/') |
492 | pathp = kbasename(pathp); | |
57d00ecf SN |
493 | rc = it(p, pathp, depth, data); |
494 | if (rc != 0) | |
495 | break; | |
496 | } while (1); | |
497 | ||
498 | return rc; | |
499 | } | |
500 | ||
501 | /** | |
502 | * of_get_flat_dt_root - find the root node in the flat blob | |
503 | */ | |
504 | unsigned long __init of_get_flat_dt_root(void) | |
505 | { | |
506 | unsigned long p = ((unsigned long)initial_boot_params) + | |
507 | be32_to_cpu(initial_boot_params->off_dt_struct); | |
508 | ||
509 | while (be32_to_cpup((__be32 *)p) == OF_DT_NOP) | |
510 | p += 4; | |
511 | BUG_ON(be32_to_cpup((__be32 *)p) != OF_DT_BEGIN_NODE); | |
512 | p += 4; | |
513 | return ALIGN(p + strlen((char *)p) + 1, 4); | |
514 | } | |
515 | ||
516 | /** | |
517 | * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr | |
518 | * | |
519 | * This function can be used within scan_flattened_dt callback to get | |
520 | * access to properties | |
521 | */ | |
522 | void *__init of_get_flat_dt_prop(unsigned long node, const char *name, | |
523 | unsigned long *size) | |
524 | { | |
525 | return of_fdt_get_property(initial_boot_params, node, name, size); | |
526 | } | |
527 | ||
528 | /** | |
529 | * of_flat_dt_is_compatible - Return true if given node has compat in compatible list | |
530 | * @node: node to test | |
531 | * @compat: compatible string to compare with compatible list. | |
532 | */ | |
533 | int __init of_flat_dt_is_compatible(unsigned long node, const char *compat) | |
534 | { | |
535 | return of_fdt_is_compatible(initial_boot_params, node, compat); | |
536 | } | |
537 | ||
a4f740cf GL |
538 | /** |
539 | * of_flat_dt_match - Return true if node matches a list of compatible values | |
540 | */ | |
7b482c83 | 541 | int __init of_flat_dt_match(unsigned long node, const char *const *compat) |
a4f740cf GL |
542 | { |
543 | return of_fdt_match(initial_boot_params, node, compat); | |
544 | } | |
545 | ||
57d74bcf MS |
546 | struct fdt_scan_status { |
547 | const char *name; | |
548 | int namelen; | |
549 | int depth; | |
550 | int found; | |
551 | int (*iterator)(unsigned long node, const char *uname, int depth, void *data); | |
552 | void *data; | |
553 | }; | |
554 | ||
555 | /** | |
556 | * fdt_scan_node_by_path - iterator for of_scan_flat_dt_by_path function | |
557 | */ | |
558 | static int __init fdt_scan_node_by_path(unsigned long node, const char *uname, | |
559 | int depth, void *data) | |
560 | { | |
561 | struct fdt_scan_status *st = data; | |
562 | ||
563 | /* | |
564 | * if scan at the requested fdt node has been completed, | |
565 | * return -ENXIO to abort further scanning | |
566 | */ | |
567 | if (depth <= st->depth) | |
568 | return -ENXIO; | |
569 | ||
570 | /* requested fdt node has been found, so call iterator function */ | |
571 | if (st->found) | |
572 | return st->iterator(node, uname, depth, st->data); | |
573 | ||
574 | /* check if scanning automata is entering next level of fdt nodes */ | |
575 | if (depth == st->depth + 1 && | |
576 | strncmp(st->name, uname, st->namelen) == 0 && | |
577 | uname[st->namelen] == 0) { | |
578 | st->depth += 1; | |
579 | if (st->name[st->namelen] == 0) { | |
580 | st->found = 1; | |
581 | } else { | |
582 | const char *next = st->name + st->namelen + 1; | |
583 | st->name = next; | |
584 | st->namelen = strcspn(next, "/"); | |
585 | } | |
586 | return 0; | |
587 | } | |
588 | ||
589 | /* scan next fdt node */ | |
590 | return 0; | |
591 | } | |
592 | ||
593 | /** | |
594 | * of_scan_flat_dt_by_path - scan flattened tree blob and call callback on each | |
595 | * child of the given path. | |
596 | * @path: path to start searching for children | |
597 | * @it: callback function | |
598 | * @data: context data pointer | |
599 | * | |
600 | * This function is used to scan the flattened device-tree starting from the | |
601 | * node given by path. It is used to extract information (like reserved | |
602 | * memory), which is required on ealy boot before we can unflatten the tree. | |
603 | */ | |
604 | int __init of_scan_flat_dt_by_path(const char *path, | |
605 | int (*it)(unsigned long node, const char *name, int depth, void *data), | |
606 | void *data) | |
607 | { | |
608 | struct fdt_scan_status st = {path, 0, -1, 0, it, data}; | |
609 | int ret = 0; | |
610 | ||
611 | if (initial_boot_params) | |
612 | ret = of_scan_flat_dt(fdt_scan_node_by_path, &st); | |
613 | ||
614 | if (!st.found) | |
615 | return -ENOENT; | |
616 | else if (ret == -ENXIO) /* scan has been completed */ | |
617 | return 0; | |
618 | else | |
619 | return ret; | |
620 | } | |
621 | ||
f7b3a835 GL |
622 | #ifdef CONFIG_BLK_DEV_INITRD |
623 | /** | |
624 | * early_init_dt_check_for_initrd - Decode initrd location from flat tree | |
625 | * @node: reference to node containing initrd location ('chosen') | |
626 | */ | |
627 | void __init early_init_dt_check_for_initrd(unsigned long node) | |
628 | { | |
374d5c99 SS |
629 | u64 start, end; |
630 | unsigned long len; | |
33714881 | 631 | __be32 *prop; |
f7b3a835 GL |
632 | |
633 | pr_debug("Looking for initrd properties... "); | |
634 | ||
635 | prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len); | |
1406bc2f JK |
636 | if (!prop) |
637 | return; | |
374d5c99 | 638 | start = of_read_number(prop, len/4); |
1406bc2f JK |
639 | |
640 | prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len); | |
641 | if (!prop) | |
642 | return; | |
374d5c99 | 643 | end = of_read_number(prop, len/4); |
f7b3a835 | 644 | |
1406bc2f | 645 | early_init_dt_setup_initrd_arch(start, end); |
374d5c99 SS |
646 | pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", |
647 | (unsigned long long)start, (unsigned long long)end); | |
f7b3a835 GL |
648 | } |
649 | #else | |
650 | inline void early_init_dt_check_for_initrd(unsigned long node) | |
651 | { | |
652 | } | |
653 | #endif /* CONFIG_BLK_DEV_INITRD */ | |
654 | ||
f00abd94 GL |
655 | /** |
656 | * early_init_dt_scan_root - fetch the top level address and size cells | |
657 | */ | |
658 | int __init early_init_dt_scan_root(unsigned long node, const char *uname, | |
659 | int depth, void *data) | |
660 | { | |
33714881 | 661 | __be32 *prop; |
f00abd94 GL |
662 | |
663 | if (depth != 0) | |
664 | return 0; | |
665 | ||
33714881 JK |
666 | dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT; |
667 | dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT; | |
668 | ||
f00abd94 | 669 | prop = of_get_flat_dt_prop(node, "#size-cells", NULL); |
33714881 JK |
670 | if (prop) |
671 | dt_root_size_cells = be32_to_cpup(prop); | |
f00abd94 GL |
672 | pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells); |
673 | ||
674 | prop = of_get_flat_dt_prop(node, "#address-cells", NULL); | |
33714881 JK |
675 | if (prop) |
676 | dt_root_addr_cells = be32_to_cpup(prop); | |
f00abd94 GL |
677 | pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells); |
678 | ||
679 | /* break now */ | |
680 | return 1; | |
681 | } | |
682 | ||
2e89e685 | 683 | u64 __init dt_mem_next_cell(int s, __be32 **cellp) |
83f7a06e | 684 | { |
2e89e685 | 685 | __be32 *p = *cellp; |
83f7a06e GL |
686 | |
687 | *cellp = p + s; | |
688 | return of_read_number(p, s); | |
689 | } | |
690 | ||
51975db0 GL |
691 | /** |
692 | * early_init_dt_scan_memory - Look for an parse memory nodes | |
693 | */ | |
694 | int __init early_init_dt_scan_memory(unsigned long node, const char *uname, | |
695 | int depth, void *data) | |
696 | { | |
697 | char *type = of_get_flat_dt_prop(node, "device_type", NULL); | |
698 | __be32 *reg, *endp; | |
699 | unsigned long l; | |
700 | ||
701 | /* We are scanning "memory" nodes only */ | |
702 | if (type == NULL) { | |
703 | /* | |
704 | * The longtrail doesn't have a device_type on the | |
705 | * /memory node, so look for the node called /memory@0. | |
706 | */ | |
707 | if (depth != 1 || strcmp(uname, "memory@0") != 0) | |
708 | return 0; | |
709 | } else if (strcmp(type, "memory") != 0) | |
710 | return 0; | |
711 | ||
712 | reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l); | |
713 | if (reg == NULL) | |
714 | reg = of_get_flat_dt_prop(node, "reg", &l); | |
715 | if (reg == NULL) | |
716 | return 0; | |
717 | ||
718 | endp = reg + (l / sizeof(__be32)); | |
719 | ||
720 | pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n", | |
721 | uname, l, reg[0], reg[1], reg[2], reg[3]); | |
722 | ||
723 | while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) { | |
724 | u64 base, size; | |
725 | ||
726 | base = dt_mem_next_cell(dt_root_addr_cells, ®); | |
727 | size = dt_mem_next_cell(dt_root_size_cells, ®); | |
728 | ||
729 | if (size == 0) | |
730 | continue; | |
731 | pr_debug(" - %llx , %llx\n", (unsigned long long)base, | |
732 | (unsigned long long)size); | |
733 | ||
734 | early_init_dt_add_memory_arch(base, size); | |
735 | } | |
736 | ||
737 | return 0; | |
738 | } | |
739 | ||
86e03221 GL |
740 | int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, |
741 | int depth, void *data) | |
742 | { | |
743 | unsigned long l; | |
744 | char *p; | |
745 | ||
746 | pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname); | |
747 | ||
85f60ae4 | 748 | if (depth != 1 || !data || |
86e03221 GL |
749 | (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0)) |
750 | return 0; | |
751 | ||
752 | early_init_dt_check_for_initrd(node); | |
753 | ||
25985edc | 754 | /* Retrieve command line */ |
86e03221 GL |
755 | p = of_get_flat_dt_prop(node, "bootargs", &l); |
756 | if (p != NULL && l > 0) | |
85f60ae4 | 757 | strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE)); |
86e03221 | 758 | |
78b782cb BH |
759 | /* |
760 | * CONFIG_CMDLINE is meant to be a default in case nothing else | |
761 | * managed to set the command line, unless CONFIG_CMDLINE_FORCE | |
762 | * is set in which case we override whatever was found earlier. | |
763 | */ | |
86e03221 GL |
764 | #ifdef CONFIG_CMDLINE |
765 | #ifndef CONFIG_CMDLINE_FORCE | |
78b782cb | 766 | if (!((char *)data)[0]) |
86e03221 | 767 | #endif |
85f60ae4 | 768 | strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE); |
86e03221 GL |
769 | #endif /* CONFIG_CMDLINE */ |
770 | ||
85f60ae4 | 771 | pr_debug("Command line is: %s\n", (char*)data); |
86e03221 GL |
772 | |
773 | /* break now */ | |
774 | return 1; | |
775 | } | |
776 | ||
a1727da5 GL |
777 | #ifdef CONFIG_HAVE_MEMBLOCK |
778 | /* | |
779 | * called from unflatten_device_tree() to bootstrap devicetree itself | |
780 | * Architectures can override this definition if memblock isn't used | |
781 | */ | |
782 | void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align) | |
783 | { | |
784 | return __va(memblock_alloc(size, align)); | |
785 | } | |
786 | #endif | |
787 | ||
41f88009 GL |
788 | /** |
789 | * unflatten_device_tree - create tree of device_nodes from flat blob | |
790 | * | |
791 | * unflattens the device-tree passed by the firmware, creating the | |
792 | * tree of struct device_node. It also fills the "name" and "type" | |
793 | * pointers of the nodes so the normal device-tree walking functions | |
794 | * can be used. | |
795 | */ | |
796 | void __init unflatten_device_tree(void) | |
797 | { | |
465aac6d | 798 | __unflatten_device_tree(initial_boot_params, &of_allnodes, |
672c5446 | 799 | early_init_dt_alloc_memory_arch); |
41f88009 | 800 | |
4c7d6361 | 801 | /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */ |
611cad72 | 802 | of_alias_scan(early_init_dt_alloc_memory_arch); |
41f88009 | 803 | } |
e6ce1324 SN |
804 | |
805 | #endif /* CONFIG_OF_EARLY_FLATTREE */ | |
109b6236 AB |
806 | |
807 | /* Feed entire flattened device tree into the random pool */ | |
808 | static int __init add_fdt_randomness(void) | |
809 | { | |
810 | if (initial_boot_params) | |
811 | add_device_randomness(initial_boot_params, | |
812 | be32_to_cpu(initial_boot_params->totalsize)); | |
813 | ||
814 | return 0; | |
815 | } | |
816 | core_initcall(add_fdt_randomness); |