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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
12#include <linux/kernel.h>
13#include <linux/initrd.h>
14#include <linux/memblock.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/of_fdt.h>
18#include <linux/of_reserved_mem.h>
19#include <linux/sizes.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/slab.h>
23
24#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
25#ifdef CONFIG_PPC
26#include <asm/machdep.h>
27#endif /* CONFIG_PPC */
28
29#include <asm/page.h>
30
31char *of_fdt_get_string(struct boot_param_header *blob, u32 offset)
32{
33 return ((char *)blob) +
34 be32_to_cpu(blob->off_dt_strings) + offset;
35}
36
37/**
38 * of_fdt_get_property - Given a node in the given flat blob, return
39 * the property ptr
40 */
41void *of_fdt_get_property(struct boot_param_header *blob,
42 unsigned long node, const char *name,
43 unsigned long *size)
44{
45 unsigned long p = node;
46
47 do {
48 u32 tag = be32_to_cpup((__be32 *)p);
49 u32 sz, noff;
50 const char *nstr;
51
52 p += 4;
53 if (tag == OF_DT_NOP)
54 continue;
55 if (tag != OF_DT_PROP)
56 return NULL;
57
58 sz = be32_to_cpup((__be32 *)p);
59 noff = be32_to_cpup((__be32 *)(p + 4));
60 p += 8;
61 if (be32_to_cpu(blob->version) < 0x10)
62 p = ALIGN(p, sz >= 8 ? 8 : 4);
63
64 nstr = of_fdt_get_string(blob, noff);
65 if (nstr == NULL) {
66 pr_warning("Can't find property index name !\n");
67 return NULL;
68 }
69 if (strcmp(name, nstr) == 0) {
70 if (size)
71 *size = sz;
72 return (void *)p;
73 }
74 p += sz;
75 p = ALIGN(p, 4);
76 } while (1);
77}
78
79/**
80 * of_fdt_is_compatible - Return true if given node from the given blob has
81 * compat in its compatible list
82 * @blob: A device tree blob
83 * @node: node to test
84 * @compat: compatible string to compare with compatible list.
85 *
86 * On match, returns a non-zero value with smaller values returned for more
87 * specific compatible values.
88 */
89int of_fdt_is_compatible(struct boot_param_header *blob,
90 unsigned long node, const char *compat)
91{
92 const char *cp;
93 unsigned long cplen, l, score = 0;
94
95 cp = of_fdt_get_property(blob, node, "compatible", &cplen);
96 if (cp == NULL)
97 return 0;
98 while (cplen > 0) {
99 score++;
100 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
101 return score;
102 l = strlen(cp) + 1;
103 cp += l;
104 cplen -= l;
105 }
106
107 return 0;
108}
109
110/**
111 * of_fdt_match - Return true if node matches a list of compatible values
112 */
113int of_fdt_match(struct boot_param_header *blob, unsigned long node,
114 const char *const *compat)
115{
116 unsigned int tmp, score = 0;
117
118 if (!compat)
119 return 0;
120
121 while (*compat) {
122 tmp = of_fdt_is_compatible(blob, node, *compat);
123 if (tmp && (score == 0 || (tmp < score)))
124 score = tmp;
125 compat++;
126 }
127
128 return score;
129}
130
131static void *unflatten_dt_alloc(void **mem, unsigned long size,
132 unsigned long align)
133{
134 void *res;
135
136 *mem = PTR_ALIGN(*mem, align);
137 res = *mem;
138 *mem += size;
139
140 return res;
141}
142
143/**
144 * unflatten_dt_node - Alloc and populate a device_node from the flat tree
145 * @blob: The parent device tree blob
146 * @mem: Memory chunk to use for allocating device nodes and properties
147 * @p: pointer to node in flat tree
148 * @dad: Parent struct device_node
149 * @allnextpp: pointer to ->allnext from last allocated device_node
150 * @fpsize: Size of the node path up at the current depth.
151 */
152static void * unflatten_dt_node(struct boot_param_header *blob,
153 void *mem,
154 void **p,
155 struct device_node *dad,
156 struct device_node ***allnextpp,
157 unsigned long fpsize)
158{
159 struct device_node *np;
160 struct property *pp, **prev_pp = NULL;
161 char *pathp;
162 u32 tag;
163 unsigned int l, allocl;
164 int has_name = 0;
165 int new_format = 0;
166
167 tag = be32_to_cpup(*p);
168 if (tag != OF_DT_BEGIN_NODE) {
169 pr_err("Weird tag at start of node: %x\n", tag);
170 return mem;
171 }
172 *p += 4;
173 pathp = *p;
174 l = allocl = strlen(pathp) + 1;
175 *p = PTR_ALIGN(*p + l, 4);
176
177 /* version 0x10 has a more compact unit name here instead of the full
178 * path. we accumulate the full path size using "fpsize", we'll rebuild
179 * it later. We detect this because the first character of the name is
180 * not '/'.
181 */
182 if ((*pathp) != '/') {
183 new_format = 1;
184 if (fpsize == 0) {
185 /* root node: special case. fpsize accounts for path
186 * plus terminating zero. root node only has '/', so
187 * fpsize should be 2, but we want to avoid the first
188 * level nodes to have two '/' so we use fpsize 1 here
189 */
190 fpsize = 1;
191 allocl = 2;
192 l = 1;
193 *pathp = '\0';
194 } else {
195 /* account for '/' and path size minus terminal 0
196 * already in 'l'
197 */
198 fpsize += l;
199 allocl = fpsize;
200 }
201 }
202
203 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
204 __alignof__(struct device_node));
205 if (allnextpp) {
206 char *fn;
207 of_node_init(np);
208 np->full_name = fn = ((char *)np) + sizeof(*np);
209 if (new_format) {
210 /* rebuild full path for new format */
211 if (dad && dad->parent) {
212 strcpy(fn, dad->full_name);
213#ifdef DEBUG
214 if ((strlen(fn) + l + 1) != allocl) {
215 pr_debug("%s: p: %d, l: %d, a: %d\n",
216 pathp, (int)strlen(fn),
217 l, allocl);
218 }
219#endif
220 fn += strlen(fn);
221 }
222 *(fn++) = '/';
223 }
224 memcpy(fn, pathp, l);
225
226 prev_pp = &np->properties;
227 **allnextpp = np;
228 *allnextpp = &np->allnext;
229 if (dad != NULL) {
230 np->parent = dad;
231 /* we temporarily use the next field as `last_child'*/
232 if (dad->next == NULL)
233 dad->child = np;
234 else
235 dad->next->sibling = np;
236 dad->next = np;
237 }
238 }
239 /* process properties */
240 while (1) {
241 u32 sz, noff;
242 char *pname;
243
244 tag = be32_to_cpup(*p);
245 if (tag == OF_DT_NOP) {
246 *p += 4;
247 continue;
248 }
249 if (tag != OF_DT_PROP)
250 break;
251 *p += 4;
252 sz = be32_to_cpup(*p);
253 noff = be32_to_cpup(*p + 4);
254 *p += 8;
255 if (be32_to_cpu(blob->version) < 0x10)
256 *p = PTR_ALIGN(*p, sz >= 8 ? 8 : 4);
257
258 pname = of_fdt_get_string(blob, noff);
259 if (pname == NULL) {
260 pr_info("Can't find property name in list !\n");
261 break;
262 }
263 if (strcmp(pname, "name") == 0)
264 has_name = 1;
265 l = strlen(pname) + 1;
266 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
267 __alignof__(struct property));
268 if (allnextpp) {
269 /* We accept flattened tree phandles either in
270 * ePAPR-style "phandle" properties, or the
271 * legacy "linux,phandle" properties. If both
272 * appear and have different values, things
273 * will get weird. Don't do that. */
274 if ((strcmp(pname, "phandle") == 0) ||
275 (strcmp(pname, "linux,phandle") == 0)) {
276 if (np->phandle == 0)
277 np->phandle = be32_to_cpup((__be32*)*p);
278 }
279 /* And we process the "ibm,phandle" property
280 * used in pSeries dynamic device tree
281 * stuff */
282 if (strcmp(pname, "ibm,phandle") == 0)
283 np->phandle = be32_to_cpup((__be32 *)*p);
284 pp->name = pname;
285 pp->length = sz;
286 pp->value = *p;
287 *prev_pp = pp;
288 prev_pp = &pp->next;
289 }
290 *p = PTR_ALIGN((*p) + sz, 4);
291 }
292 /* with version 0x10 we may not have the name property, recreate
293 * it here from the unit name if absent
294 */
295 if (!has_name) {
296 char *p1 = pathp, *ps = pathp, *pa = NULL;
297 int sz;
298
299 while (*p1) {
300 if ((*p1) == '@')
301 pa = p1;
302 if ((*p1) == '/')
303 ps = p1 + 1;
304 p1++;
305 }
306 if (pa < ps)
307 pa = p1;
308 sz = (pa - ps) + 1;
309 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
310 __alignof__(struct property));
311 if (allnextpp) {
312 pp->name = "name";
313 pp->length = sz;
314 pp->value = pp + 1;
315 *prev_pp = pp;
316 prev_pp = &pp->next;
317 memcpy(pp->value, ps, sz - 1);
318 ((char *)pp->value)[sz - 1] = 0;
319 pr_debug("fixed up name for %s -> %s\n", pathp,
320 (char *)pp->value);
321 }
322 }
323 if (allnextpp) {
324 *prev_pp = NULL;
325 np->name = of_get_property(np, "name", NULL);
326 np->type = of_get_property(np, "device_type", NULL);
327
328 if (!np->name)
329 np->name = "<NULL>";
330 if (!np->type)
331 np->type = "<NULL>";
332 }
333 while (tag == OF_DT_BEGIN_NODE || tag == OF_DT_NOP) {
334 if (tag == OF_DT_NOP)
335 *p += 4;
336 else
337 mem = unflatten_dt_node(blob, mem, p, np, allnextpp,
338 fpsize);
339 tag = be32_to_cpup(*p);
340 }
341 if (tag != OF_DT_END_NODE) {
342 pr_err("Weird tag at end of node: %x\n", tag);
343 return mem;
344 }
345 *p += 4;
346 return mem;
347}
348
349/**
350 * __unflatten_device_tree - create tree of device_nodes from flat blob
351 *
352 * unflattens a device-tree, creating the
353 * tree of struct device_node. It also fills the "name" and "type"
354 * pointers of the nodes so the normal device-tree walking functions
355 * can be used.
356 * @blob: The blob to expand
357 * @mynodes: The device_node tree created by the call
358 * @dt_alloc: An allocator that provides a virtual address to memory
359 * for the resulting tree
360 */
361static void __unflatten_device_tree(struct boot_param_header *blob,
362 struct device_node **mynodes,
363 void * (*dt_alloc)(u64 size, u64 align))
364{
365 unsigned long size;
366 void *start, *mem;
367 struct device_node **allnextp = mynodes;
368
369 pr_debug(" -> unflatten_device_tree()\n");
370
371 if (!blob) {
372 pr_debug("No device tree pointer\n");
373 return;
374 }
375
376 pr_debug("Unflattening device tree:\n");
377 pr_debug("magic: %08x\n", be32_to_cpu(blob->magic));
378 pr_debug("size: %08x\n", be32_to_cpu(blob->totalsize));
379 pr_debug("version: %08x\n", be32_to_cpu(blob->version));
380
381 if (be32_to_cpu(blob->magic) != OF_DT_HEADER) {
382 pr_err("Invalid device tree blob header\n");
383 return;
384 }
385
386 /* First pass, scan for size */
387 start = ((void *)blob) + be32_to_cpu(blob->off_dt_struct);
388 size = (unsigned long)unflatten_dt_node(blob, 0, &start, NULL, NULL, 0);
389 size = ALIGN(size, 4);
390
391 pr_debug(" size is %lx, allocating...\n", size);
392
393 /* Allocate memory for the expanded device tree */
394 mem = dt_alloc(size + 4, __alignof__(struct device_node));
395 memset(mem, 0, size);
396
397 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
398
399 pr_debug(" unflattening %p...\n", mem);
400
401 /* Second pass, do actual unflattening */
402 start = ((void *)blob) + be32_to_cpu(blob->off_dt_struct);
403 unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0);
404 if (be32_to_cpup(start) != OF_DT_END)
405 pr_warning("Weird tag at end of tree: %08x\n", be32_to_cpup(start));
406 if (be32_to_cpup(mem + size) != 0xdeadbeef)
407 pr_warning("End of tree marker overwritten: %08x\n",
408 be32_to_cpup(mem + size));
409 *allnextp = NULL;
410
411 pr_debug(" <- unflatten_device_tree()\n");
412}
413
414static void *kernel_tree_alloc(u64 size, u64 align)
415{
416 return kzalloc(size, GFP_KERNEL);
417}
418
419/**
420 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
421 *
422 * unflattens the device-tree passed by the firmware, creating the
423 * tree of struct device_node. It also fills the "name" and "type"
424 * pointers of the nodes so the normal device-tree walking functions
425 * can be used.
426 */
427void of_fdt_unflatten_tree(unsigned long *blob,
428 struct device_node **mynodes)
429{
430 struct boot_param_header *device_tree =
431 (struct boot_param_header *)blob;
432 __unflatten_device_tree(device_tree, mynodes, &kernel_tree_alloc);
433}
434EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
435
436/* Everything below here references initial_boot_params directly. */
437int __initdata dt_root_addr_cells;
438int __initdata dt_root_size_cells;
439
440struct boot_param_header *initial_boot_params;
441
442#ifdef CONFIG_OF_EARLY_FLATTREE
443
444/**
445 * res_mem_reserve_reg() - reserve all memory described in 'reg' property
446 */
447static int __init __reserved_mem_reserve_reg(unsigned long node,
448 const char *uname)
449{
450 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
451 phys_addr_t base, size;
452 unsigned long len;
453 __be32 *prop;
454 int nomap, first = 1;
455
456 prop = of_get_flat_dt_prop(node, "reg", &len);
457 if (!prop)
458 return -ENOENT;
459
460 if (len && len % t_len != 0) {
461 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
462 uname);
463 return -EINVAL;
464 }
465
466 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
467
468 while (len >= t_len) {
469 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
470 size = dt_mem_next_cell(dt_root_size_cells, &prop);
471
472 if (base && size &&
473 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
474 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
475 uname, &base, (unsigned long)size / SZ_1M);
476 else
477 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
478 uname, &base, (unsigned long)size / SZ_1M);
479
480 len -= t_len;
481 if (first) {
482 fdt_reserved_mem_save_node(node, uname, base, size);
483 first = 0;
484 }
485 }
486 return 0;
487}
488
489/**
490 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
491 * in /reserved-memory matches the values supported by the current implementation,
492 * also check if ranges property has been provided
493 */
494static int __init __reserved_mem_check_root(unsigned long node)
495{
496 __be32 *prop;
497
498 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
499 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
500 return -EINVAL;
501
502 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
503 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
504 return -EINVAL;
505
506 prop = of_get_flat_dt_prop(node, "ranges", NULL);
507 if (!prop)
508 return -EINVAL;
509 return 0;
510}
511
512/**
513 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
514 */
515static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
516 int depth, void *data)
517{
518 static int found;
519 const char *status;
520 int err;
521
522 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
523 if (__reserved_mem_check_root(node) != 0) {
524 pr_err("Reserved memory: unsupported node format, ignoring\n");
525 /* break scan */
526 return 1;
527 }
528 found = 1;
529 /* scan next node */
530 return 0;
531 } else if (!found) {
532 /* scan next node */
533 return 0;
534 } else if (found && depth < 2) {
535 /* scanning of /reserved-memory has been finished */
536 return 1;
537 }
538
539 status = of_get_flat_dt_prop(node, "status", NULL);
540 if (status && strcmp(status, "okay") != 0 && strcmp(status, "ok") != 0)
541 return 0;
542
543 err = __reserved_mem_reserve_reg(node, uname);
544 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
545 fdt_reserved_mem_save_node(node, uname, 0, 0);
546
547 /* scan next node */
548 return 0;
549}
550
551/**
552 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
553 *
554 * This function grabs memory from early allocator for device exclusive use
555 * defined in device tree structures. It should be called by arch specific code
556 * once the early allocator (i.e. memblock) has been fully activated.
557 */
558void __init early_init_fdt_scan_reserved_mem(void)
559{
560 if (!initial_boot_params)
561 return;
562
563 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
564 fdt_init_reserved_mem();
565}
566
567/**
568 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
569 * @it: callback function
570 * @data: context data pointer
571 *
572 * This function is used to scan the flattened device-tree, it is
573 * used to extract the memory information at boot before we can
574 * unflatten the tree
575 */
576int __init of_scan_flat_dt(int (*it)(unsigned long node,
577 const char *uname, int depth,
578 void *data),
579 void *data)
580{
581 unsigned long p = ((unsigned long)initial_boot_params) +
582 be32_to_cpu(initial_boot_params->off_dt_struct);
583 int rc = 0;
584 int depth = -1;
585
586 do {
587 u32 tag = be32_to_cpup((__be32 *)p);
588 const char *pathp;
589
590 p += 4;
591 if (tag == OF_DT_END_NODE) {
592 depth--;
593 continue;
594 }
595 if (tag == OF_DT_NOP)
596 continue;
597 if (tag == OF_DT_END)
598 break;
599 if (tag == OF_DT_PROP) {
600 u32 sz = be32_to_cpup((__be32 *)p);
601 p += 8;
602 if (be32_to_cpu(initial_boot_params->version) < 0x10)
603 p = ALIGN(p, sz >= 8 ? 8 : 4);
604 p += sz;
605 p = ALIGN(p, 4);
606 continue;
607 }
608 if (tag != OF_DT_BEGIN_NODE) {
609 pr_err("Invalid tag %x in flat device tree!\n", tag);
610 return -EINVAL;
611 }
612 depth++;
613 pathp = (char *)p;
614 p = ALIGN(p + strlen(pathp) + 1, 4);
615 if (*pathp == '/')
616 pathp = kbasename(pathp);
617 rc = it(p, pathp, depth, data);
618 if (rc != 0)
619 break;
620 } while (1);
621
622 return rc;
623}
624
625/**
626 * of_get_flat_dt_root - find the root node in the flat blob
627 */
628unsigned long __init of_get_flat_dt_root(void)
629{
630 unsigned long p = ((unsigned long)initial_boot_params) +
631 be32_to_cpu(initial_boot_params->off_dt_struct);
632
633 while (be32_to_cpup((__be32 *)p) == OF_DT_NOP)
634 p += 4;
635 BUG_ON(be32_to_cpup((__be32 *)p) != OF_DT_BEGIN_NODE);
636 p += 4;
637 return ALIGN(p + strlen((char *)p) + 1, 4);
638}
639
640/**
641 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
642 *
643 * This function can be used within scan_flattened_dt callback to get
644 * access to properties
645 */
646void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
647 unsigned long *size)
648{
649 return of_fdt_get_property(initial_boot_params, node, name, size);
650}
651
652/**
653 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
654 * @node: node to test
655 * @compat: compatible string to compare with compatible list.
656 */
657int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
658{
659 return of_fdt_is_compatible(initial_boot_params, node, compat);
660}
661
662/**
663 * of_flat_dt_match - Return true if node matches a list of compatible values
664 */
665int __init of_flat_dt_match(unsigned long node, const char *const *compat)
666{
667 return of_fdt_match(initial_boot_params, node, compat);
668}
669
670struct fdt_scan_status {
671 const char *name;
672 int namelen;
673 int depth;
674 int found;
675 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
676 void *data;
677};
678
679/**
680 * fdt_scan_node_by_path - iterator for of_scan_flat_dt_by_path function
681 */
682static int __init fdt_scan_node_by_path(unsigned long node, const char *uname,
683 int depth, void *data)
684{
685 struct fdt_scan_status *st = data;
686
687 /*
688 * if scan at the requested fdt node has been completed,
689 * return -ENXIO to abort further scanning
690 */
691 if (depth <= st->depth)
692 return -ENXIO;
693
694 /* requested fdt node has been found, so call iterator function */
695 if (st->found)
696 return st->iterator(node, uname, depth, st->data);
697
698 /* check if scanning automata is entering next level of fdt nodes */
699 if (depth == st->depth + 1 &&
700 strncmp(st->name, uname, st->namelen) == 0 &&
701 uname[st->namelen] == 0) {
702 st->depth += 1;
703 if (st->name[st->namelen] == 0) {
704 st->found = 1;
705 } else {
706 const char *next = st->name + st->namelen + 1;
707 st->name = next;
708 st->namelen = strcspn(next, "/");
709 }
710 return 0;
711 }
712
713 /* scan next fdt node */
714 return 0;
715}
716
717/**
718 * of_scan_flat_dt_by_path - scan flattened tree blob and call callback on each
719 * child of the given path.
720 * @path: path to start searching for children
721 * @it: callback function
722 * @data: context data pointer
723 *
724 * This function is used to scan the flattened device-tree starting from the
725 * node given by path. It is used to extract information (like reserved
726 * memory), which is required on ealy boot before we can unflatten the tree.
727 */
728int __init of_scan_flat_dt_by_path(const char *path,
729 int (*it)(unsigned long node, const char *name, int depth, void *data),
730 void *data)
731{
732 struct fdt_scan_status st = {path, 0, -1, 0, it, data};
733 int ret = 0;
734
735 if (initial_boot_params)
736 ret = of_scan_flat_dt(fdt_scan_node_by_path, &st);
737
738 if (!st.found)
739 return -ENOENT;
740 else if (ret == -ENXIO) /* scan has been completed */
741 return 0;
742 else
743 return ret;
744}
745
746const char * __init of_flat_dt_get_machine_name(void)
747{
748 const char *name;
749 unsigned long dt_root = of_get_flat_dt_root();
750
751 name = of_get_flat_dt_prop(dt_root, "model", NULL);
752 if (!name)
753 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
754 return name;
755}
756
757/**
758 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
759 *
760 * @default_match: A machine specific ptr to return in case of no match.
761 * @get_next_compat: callback function to return next compatible match table.
762 *
763 * Iterate through machine match tables to find the best match for the machine
764 * compatible string in the FDT.
765 */
766const void * __init of_flat_dt_match_machine(const void *default_match,
767 const void * (*get_next_compat)(const char * const**))
768{
769 const void *data = NULL;
770 const void *best_data = default_match;
771 const char *const *compat;
772 unsigned long dt_root;
773 unsigned int best_score = ~1, score = 0;
774
775 dt_root = of_get_flat_dt_root();
776 while ((data = get_next_compat(&compat))) {
777 score = of_flat_dt_match(dt_root, compat);
778 if (score > 0 && score < best_score) {
779 best_data = data;
780 best_score = score;
781 }
782 }
783 if (!best_data) {
784 const char *prop;
785 long size;
786
787 pr_err("\n unrecognized device tree list:\n[ ");
788
789 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
790 if (prop) {
791 while (size > 0) {
792 printk("'%s' ", prop);
793 size -= strlen(prop) + 1;
794 prop += strlen(prop) + 1;
795 }
796 }
797 printk("]\n\n");
798 return NULL;
799 }
800
801 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
802
803 return best_data;
804}
805
806#ifdef CONFIG_BLK_DEV_INITRD
807/**
808 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
809 * @node: reference to node containing initrd location ('chosen')
810 */
811static void __init early_init_dt_check_for_initrd(unsigned long node)
812{
813 u64 start, end;
814 unsigned long len;
815 __be32 *prop;
816
817 pr_debug("Looking for initrd properties... ");
818
819 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
820 if (!prop)
821 return;
822 start = of_read_number(prop, len/4);
823
824 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
825 if (!prop)
826 return;
827 end = of_read_number(prop, len/4);
828
829 initrd_start = (unsigned long)__va(start);
830 initrd_end = (unsigned long)__va(end);
831 initrd_below_start_ok = 1;
832
833 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n",
834 (unsigned long long)start, (unsigned long long)end);
835}
836#else
837static inline void early_init_dt_check_for_initrd(unsigned long node)
838{
839}
840#endif /* CONFIG_BLK_DEV_INITRD */
841
842/**
843 * early_init_dt_scan_root - fetch the top level address and size cells
844 */
845int __init early_init_dt_scan_root(unsigned long node, const char *uname,
846 int depth, void *data)
847{
848 __be32 *prop;
849
850 if (depth != 0)
851 return 0;
852
853 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
854 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
855
856 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
857 if (prop)
858 dt_root_size_cells = be32_to_cpup(prop);
859 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
860
861 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
862 if (prop)
863 dt_root_addr_cells = be32_to_cpup(prop);
864 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
865
866 /* break now */
867 return 1;
868}
869
870u64 __init dt_mem_next_cell(int s, __be32 **cellp)
871{
872 __be32 *p = *cellp;
873
874 *cellp = p + s;
875 return of_read_number(p, s);
876}
877
878/**
879 * early_init_dt_scan_memory - Look for an parse memory nodes
880 */
881int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
882 int depth, void *data)
883{
884 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
885 __be32 *reg, *endp;
886 unsigned long l;
887
888 /* We are scanning "memory" nodes only */
889 if (type == NULL) {
890 /*
891 * The longtrail doesn't have a device_type on the
892 * /memory node, so look for the node called /memory@0.
893 */
894 if (depth != 1 || strcmp(uname, "memory@0") != 0)
895 return 0;
896 } else if (strcmp(type, "memory") != 0)
897 return 0;
898
899 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
900 if (reg == NULL)
901 reg = of_get_flat_dt_prop(node, "reg", &l);
902 if (reg == NULL)
903 return 0;
904
905 endp = reg + (l / sizeof(__be32));
906
907 pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
908 uname, l, reg[0], reg[1], reg[2], reg[3]);
909
910 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
911 u64 base, size;
912
913 base = dt_mem_next_cell(dt_root_addr_cells, ®);
914 size = dt_mem_next_cell(dt_root_size_cells, ®);
915
916 if (size == 0)
917 continue;
918 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
919 (unsigned long long)size);
920
921 early_init_dt_add_memory_arch(base, size);
922 }
923
924 return 0;
925}
926
927int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
928 int depth, void *data)
929{
930 unsigned long l;
931 char *p;
932
933 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
934
935 if (depth != 1 || !data ||
936 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
937 return 0;
938
939 early_init_dt_check_for_initrd(node);
940
941 /* Retrieve command line */
942 p = of_get_flat_dt_prop(node, "bootargs", &l);
943 if (p != NULL && l > 0)
944 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
945
946 /*
947 * CONFIG_CMDLINE is meant to be a default in case nothing else
948 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
949 * is set in which case we override whatever was found earlier.
950 */
951#ifdef CONFIG_CMDLINE
952#ifndef CONFIG_CMDLINE_FORCE
953 if (!((char *)data)[0])
954#endif
955 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
956#endif /* CONFIG_CMDLINE */
957
958 pr_debug("Command line is: %s\n", (char*)data);
959
960 /* break now */
961 return 1;
962}
963
964#ifdef CONFIG_HAVE_MEMBLOCK
965void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
966{
967 const u64 phys_offset = __pa(PAGE_OFFSET);
968 base &= PAGE_MASK;
969 size &= PAGE_MASK;
970 if (base + size < phys_offset) {
971 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
972 base, base + size);
973 return;
974 }
975 if (base < phys_offset) {
976 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
977 base, phys_offset);
978 size -= phys_offset - base;
979 base = phys_offset;
980 }
981 memblock_add(base, size);
982}
983
984int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
985 phys_addr_t size, bool nomap)
986{
987 if (memblock_is_region_reserved(base, size))
988 return -EBUSY;
989 if (nomap)
990 return memblock_remove(base, size);
991 return memblock_reserve(base, size);
992}
993
994/*
995 * called from unflatten_device_tree() to bootstrap devicetree itself
996 * Architectures can override this definition if memblock isn't used
997 */
998void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
999{
1000 return __va(memblock_alloc(size, align));
1001}
1002#else
1003int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1004 phys_addr_t size, bool nomap)
1005{
1006 pr_err("Reserved memory not supported, ignoring range 0x%llx - 0x%llx%s\n",
1007 base, size, nomap ? " (nomap)" : "");
1008 return -ENOSYS;
1009}
1010#endif
1011
1012bool __init early_init_dt_scan(void *params)
1013{
1014 if (!params)
1015 return false;
1016
1017 /* Setup flat device-tree pointer */
1018 initial_boot_params = params;
1019
1020 /* check device tree validity */
1021 if (be32_to_cpu(initial_boot_params->magic) != OF_DT_HEADER) {
1022 initial_boot_params = NULL;
1023 return false;
1024 }
1025
1026 /* Retrieve various information from the /chosen node */
1027 of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1028
1029 /* Initialize {size,address}-cells info */
1030 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1031
1032 /* Setup memory, calling early_init_dt_add_memory_arch */
1033 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1034
1035 return true;
1036}
1037
1038/**
1039 * unflatten_device_tree - create tree of device_nodes from flat blob
1040 *
1041 * unflattens the device-tree passed by the firmware, creating the
1042 * tree of struct device_node. It also fills the "name" and "type"
1043 * pointers of the nodes so the normal device-tree walking functions
1044 * can be used.
1045 */
1046void __init unflatten_device_tree(void)
1047{
1048 __unflatten_device_tree(initial_boot_params, &of_allnodes,
1049 early_init_dt_alloc_memory_arch);
1050
1051 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1052 of_alias_scan(early_init_dt_alloc_memory_arch);
1053}
1054
1055/**
1056 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1057 *
1058 * Copies and unflattens the device-tree passed by the firmware, creating the
1059 * tree of struct device_node. It also fills the "name" and "type"
1060 * pointers of the nodes so the normal device-tree walking functions
1061 * can be used. This should only be used when the FDT memory has not been
1062 * reserved such is the case when the FDT is built-in to the kernel init
1063 * section. If the FDT memory is reserved already then unflatten_device_tree
1064 * should be used instead.
1065 */
1066void __init unflatten_and_copy_device_tree(void)
1067{
1068 int size;
1069 void *dt;
1070
1071 if (!initial_boot_params) {
1072 pr_warn("No valid device tree found, continuing without\n");
1073 return;
1074 }
1075
1076 size = __be32_to_cpu(initial_boot_params->totalsize);
1077 dt = early_init_dt_alloc_memory_arch(size,
1078 __alignof__(struct boot_param_header));
1079
1080 if (dt) {
1081 memcpy(dt, initial_boot_params, size);
1082 initial_boot_params = dt;
1083 }
1084 unflatten_device_tree();
1085}
1086
1087#endif /* CONFIG_OF_EARLY_FLATTREE */
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
12#include <linux/kernel.h>
13#include <linux/initrd.h>
14#include <linux/module.h>
15#include <linux/of.h>
16#include <linux/of_fdt.h>
17#include <linux/string.h>
18#include <linux/errno.h>
19#include <linux/slab.h>
20
21#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
22#ifdef CONFIG_PPC
23#include <asm/machdep.h>
24#endif /* CONFIG_PPC */
25
26#include <asm/page.h>
27
28char *of_fdt_get_string(struct boot_param_header *blob, u32 offset)
29{
30 return ((char *)blob) +
31 be32_to_cpu(blob->off_dt_strings) + offset;
32}
33
34/**
35 * of_fdt_get_property - Given a node in the given flat blob, return
36 * the property ptr
37 */
38void *of_fdt_get_property(struct boot_param_header *blob,
39 unsigned long node, const char *name,
40 unsigned long *size)
41{
42 unsigned long p = node;
43
44 do {
45 u32 tag = be32_to_cpup((__be32 *)p);
46 u32 sz, noff;
47 const char *nstr;
48
49 p += 4;
50 if (tag == OF_DT_NOP)
51 continue;
52 if (tag != OF_DT_PROP)
53 return NULL;
54
55 sz = be32_to_cpup((__be32 *)p);
56 noff = be32_to_cpup((__be32 *)(p + 4));
57 p += 8;
58 if (be32_to_cpu(blob->version) < 0x10)
59 p = ALIGN(p, sz >= 8 ? 8 : 4);
60
61 nstr = of_fdt_get_string(blob, noff);
62 if (nstr == NULL) {
63 pr_warning("Can't find property index name !\n");
64 return NULL;
65 }
66 if (strcmp(name, nstr) == 0) {
67 if (size)
68 *size = sz;
69 return (void *)p;
70 }
71 p += sz;
72 p = ALIGN(p, 4);
73 } while (1);
74}
75
76/**
77 * of_fdt_is_compatible - Return true if given node from the given blob has
78 * compat in its compatible list
79 * @blob: A device tree blob
80 * @node: node to test
81 * @compat: compatible string to compare with compatible list.
82 *
83 * On match, returns a non-zero value with smaller values returned for more
84 * specific compatible values.
85 */
86int of_fdt_is_compatible(struct boot_param_header *blob,
87 unsigned long node, const char *compat)
88{
89 const char *cp;
90 unsigned long cplen, l, score = 0;
91
92 cp = of_fdt_get_property(blob, node, "compatible", &cplen);
93 if (cp == NULL)
94 return 0;
95 while (cplen > 0) {
96 score++;
97 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
98 return score;
99 l = strlen(cp) + 1;
100 cp += l;
101 cplen -= l;
102 }
103
104 return 0;
105}
106
107/**
108 * of_fdt_match - Return true if node matches a list of compatible values
109 */
110int of_fdt_match(struct boot_param_header *blob, unsigned long node,
111 const char *const *compat)
112{
113 unsigned int tmp, score = 0;
114
115 if (!compat)
116 return 0;
117
118 while (*compat) {
119 tmp = of_fdt_is_compatible(blob, node, *compat);
120 if (tmp && (score == 0 || (tmp < score)))
121 score = tmp;
122 compat++;
123 }
124
125 return score;
126}
127
128static void *unflatten_dt_alloc(unsigned long *mem, unsigned long size,
129 unsigned long align)
130{
131 void *res;
132
133 *mem = ALIGN(*mem, align);
134 res = (void *)*mem;
135 *mem += size;
136
137 return res;
138}
139
140/**
141 * unflatten_dt_node - Alloc and populate a device_node from the flat tree
142 * @blob: The parent device tree blob
143 * @mem: Memory chunk to use for allocating device nodes and properties
144 * @p: pointer to node in flat tree
145 * @dad: Parent struct device_node
146 * @allnextpp: pointer to ->allnext from last allocated device_node
147 * @fpsize: Size of the node path up at the current depth.
148 */
149static unsigned long unflatten_dt_node(struct boot_param_header *blob,
150 unsigned long mem,
151 unsigned long *p,
152 struct device_node *dad,
153 struct device_node ***allnextpp,
154 unsigned long fpsize)
155{
156 struct device_node *np;
157 struct property *pp, **prev_pp = NULL;
158 char *pathp;
159 u32 tag;
160 unsigned int l, allocl;
161 int has_name = 0;
162 int new_format = 0;
163
164 tag = be32_to_cpup((__be32 *)(*p));
165 if (tag != OF_DT_BEGIN_NODE) {
166 pr_err("Weird tag at start of node: %x\n", tag);
167 return mem;
168 }
169 *p += 4;
170 pathp = (char *)*p;
171 l = allocl = strlen(pathp) + 1;
172 *p = ALIGN(*p + l, 4);
173
174 /* version 0x10 has a more compact unit name here instead of the full
175 * path. we accumulate the full path size using "fpsize", we'll rebuild
176 * it later. We detect this because the first character of the name is
177 * not '/'.
178 */
179 if ((*pathp) != '/') {
180 new_format = 1;
181 if (fpsize == 0) {
182 /* root node: special case. fpsize accounts for path
183 * plus terminating zero. root node only has '/', so
184 * fpsize should be 2, but we want to avoid the first
185 * level nodes to have two '/' so we use fpsize 1 here
186 */
187 fpsize = 1;
188 allocl = 2;
189 } else {
190 /* account for '/' and path size minus terminal 0
191 * already in 'l'
192 */
193 fpsize += l;
194 allocl = fpsize;
195 }
196 }
197
198 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
199 __alignof__(struct device_node));
200 if (allnextpp) {
201 memset(np, 0, sizeof(*np));
202 np->full_name = ((char *)np) + sizeof(struct device_node);
203 if (new_format) {
204 char *fn = np->full_name;
205 /* rebuild full path for new format */
206 if (dad && dad->parent) {
207 strcpy(fn, dad->full_name);
208#ifdef DEBUG
209 if ((strlen(fn) + l + 1) != allocl) {
210 pr_debug("%s: p: %d, l: %d, a: %d\n",
211 pathp, (int)strlen(fn),
212 l, allocl);
213 }
214#endif
215 fn += strlen(fn);
216 }
217 *(fn++) = '/';
218 memcpy(fn, pathp, l);
219 } else
220 memcpy(np->full_name, pathp, l);
221 prev_pp = &np->properties;
222 **allnextpp = np;
223 *allnextpp = &np->allnext;
224 if (dad != NULL) {
225 np->parent = dad;
226 /* we temporarily use the next field as `last_child'*/
227 if (dad->next == NULL)
228 dad->child = np;
229 else
230 dad->next->sibling = np;
231 dad->next = np;
232 }
233 kref_init(&np->kref);
234 }
235 /* process properties */
236 while (1) {
237 u32 sz, noff;
238 char *pname;
239
240 tag = be32_to_cpup((__be32 *)(*p));
241 if (tag == OF_DT_NOP) {
242 *p += 4;
243 continue;
244 }
245 if (tag != OF_DT_PROP)
246 break;
247 *p += 4;
248 sz = be32_to_cpup((__be32 *)(*p));
249 noff = be32_to_cpup((__be32 *)((*p) + 4));
250 *p += 8;
251 if (be32_to_cpu(blob->version) < 0x10)
252 *p = ALIGN(*p, sz >= 8 ? 8 : 4);
253
254 pname = of_fdt_get_string(blob, noff);
255 if (pname == NULL) {
256 pr_info("Can't find property name in list !\n");
257 break;
258 }
259 if (strcmp(pname, "name") == 0)
260 has_name = 1;
261 l = strlen(pname) + 1;
262 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
263 __alignof__(struct property));
264 if (allnextpp) {
265 /* We accept flattened tree phandles either in
266 * ePAPR-style "phandle" properties, or the
267 * legacy "linux,phandle" properties. If both
268 * appear and have different values, things
269 * will get weird. Don't do that. */
270 if ((strcmp(pname, "phandle") == 0) ||
271 (strcmp(pname, "linux,phandle") == 0)) {
272 if (np->phandle == 0)
273 np->phandle = be32_to_cpup((__be32*)*p);
274 }
275 /* And we process the "ibm,phandle" property
276 * used in pSeries dynamic device tree
277 * stuff */
278 if (strcmp(pname, "ibm,phandle") == 0)
279 np->phandle = be32_to_cpup((__be32 *)*p);
280 pp->name = pname;
281 pp->length = sz;
282 pp->value = (void *)*p;
283 *prev_pp = pp;
284 prev_pp = &pp->next;
285 }
286 *p = ALIGN((*p) + sz, 4);
287 }
288 /* with version 0x10 we may not have the name property, recreate
289 * it here from the unit name if absent
290 */
291 if (!has_name) {
292 char *p1 = pathp, *ps = pathp, *pa = NULL;
293 int sz;
294
295 while (*p1) {
296 if ((*p1) == '@')
297 pa = p1;
298 if ((*p1) == '/')
299 ps = p1 + 1;
300 p1++;
301 }
302 if (pa < ps)
303 pa = p1;
304 sz = (pa - ps) + 1;
305 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
306 __alignof__(struct property));
307 if (allnextpp) {
308 pp->name = "name";
309 pp->length = sz;
310 pp->value = pp + 1;
311 *prev_pp = pp;
312 prev_pp = &pp->next;
313 memcpy(pp->value, ps, sz - 1);
314 ((char *)pp->value)[sz - 1] = 0;
315 pr_debug("fixed up name for %s -> %s\n", pathp,
316 (char *)pp->value);
317 }
318 }
319 if (allnextpp) {
320 *prev_pp = NULL;
321 np->name = of_get_property(np, "name", NULL);
322 np->type = of_get_property(np, "device_type", NULL);
323
324 if (!np->name)
325 np->name = "<NULL>";
326 if (!np->type)
327 np->type = "<NULL>";
328 }
329 while (tag == OF_DT_BEGIN_NODE || tag == OF_DT_NOP) {
330 if (tag == OF_DT_NOP)
331 *p += 4;
332 else
333 mem = unflatten_dt_node(blob, mem, p, np, allnextpp,
334 fpsize);
335 tag = be32_to_cpup((__be32 *)(*p));
336 }
337 if (tag != OF_DT_END_NODE) {
338 pr_err("Weird tag at end of node: %x\n", tag);
339 return mem;
340 }
341 *p += 4;
342 return mem;
343}
344
345/**
346 * __unflatten_device_tree - create tree of device_nodes from flat blob
347 *
348 * unflattens a device-tree, creating the
349 * tree of struct device_node. It also fills the "name" and "type"
350 * pointers of the nodes so the normal device-tree walking functions
351 * can be used.
352 * @blob: The blob to expand
353 * @mynodes: The device_node tree created by the call
354 * @dt_alloc: An allocator that provides a virtual address to memory
355 * for the resulting tree
356 */
357static void __unflatten_device_tree(struct boot_param_header *blob,
358 struct device_node **mynodes,
359 void * (*dt_alloc)(u64 size, u64 align))
360{
361 unsigned long start, mem, size;
362 struct device_node **allnextp = mynodes;
363
364 pr_debug(" -> unflatten_device_tree()\n");
365
366 if (!blob) {
367 pr_debug("No device tree pointer\n");
368 return;
369 }
370
371 pr_debug("Unflattening device tree:\n");
372 pr_debug("magic: %08x\n", be32_to_cpu(blob->magic));
373 pr_debug("size: %08x\n", be32_to_cpu(blob->totalsize));
374 pr_debug("version: %08x\n", be32_to_cpu(blob->version));
375
376 if (be32_to_cpu(blob->magic) != OF_DT_HEADER) {
377 pr_err("Invalid device tree blob header\n");
378 return;
379 }
380
381 /* First pass, scan for size */
382 start = ((unsigned long)blob) +
383 be32_to_cpu(blob->off_dt_struct);
384 size = unflatten_dt_node(blob, 0, &start, NULL, NULL, 0);
385 size = (size | 3) + 1;
386
387 pr_debug(" size is %lx, allocating...\n", size);
388
389 /* Allocate memory for the expanded device tree */
390 mem = (unsigned long)
391 dt_alloc(size + 4, __alignof__(struct device_node));
392
393 ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef);
394
395 pr_debug(" unflattening %lx...\n", mem);
396
397 /* Second pass, do actual unflattening */
398 start = ((unsigned long)blob) +
399 be32_to_cpu(blob->off_dt_struct);
400 unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0);
401 if (be32_to_cpup((__be32 *)start) != OF_DT_END)
402 pr_warning("Weird tag at end of tree: %08x\n", *((u32 *)start));
403 if (be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeef)
404 pr_warning("End of tree marker overwritten: %08x\n",
405 be32_to_cpu(((__be32 *)mem)[size / 4]));
406 *allnextp = NULL;
407
408 pr_debug(" <- unflatten_device_tree()\n");
409}
410
411static void *kernel_tree_alloc(u64 size, u64 align)
412{
413 return kzalloc(size, GFP_KERNEL);
414}
415
416/**
417 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
418 *
419 * unflattens the device-tree passed by the firmware, creating the
420 * tree of struct device_node. It also fills the "name" and "type"
421 * pointers of the nodes so the normal device-tree walking functions
422 * can be used.
423 */
424void of_fdt_unflatten_tree(unsigned long *blob,
425 struct device_node **mynodes)
426{
427 struct boot_param_header *device_tree =
428 (struct boot_param_header *)blob;
429 __unflatten_device_tree(device_tree, mynodes, &kernel_tree_alloc);
430}
431EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
432
433/* Everything below here references initial_boot_params directly. */
434int __initdata dt_root_addr_cells;
435int __initdata dt_root_size_cells;
436
437struct boot_param_header *initial_boot_params;
438
439#ifdef CONFIG_OF_EARLY_FLATTREE
440
441/**
442 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
443 * @it: callback function
444 * @data: context data pointer
445 *
446 * This function is used to scan the flattened device-tree, it is
447 * used to extract the memory information at boot before we can
448 * unflatten the tree
449 */
450int __init of_scan_flat_dt(int (*it)(unsigned long node,
451 const char *uname, int depth,
452 void *data),
453 void *data)
454{
455 unsigned long p = ((unsigned long)initial_boot_params) +
456 be32_to_cpu(initial_boot_params->off_dt_struct);
457 int rc = 0;
458 int depth = -1;
459
460 do {
461 u32 tag = be32_to_cpup((__be32 *)p);
462 char *pathp;
463
464 p += 4;
465 if (tag == OF_DT_END_NODE) {
466 depth--;
467 continue;
468 }
469 if (tag == OF_DT_NOP)
470 continue;
471 if (tag == OF_DT_END)
472 break;
473 if (tag == OF_DT_PROP) {
474 u32 sz = be32_to_cpup((__be32 *)p);
475 p += 8;
476 if (be32_to_cpu(initial_boot_params->version) < 0x10)
477 p = ALIGN(p, sz >= 8 ? 8 : 4);
478 p += sz;
479 p = ALIGN(p, 4);
480 continue;
481 }
482 if (tag != OF_DT_BEGIN_NODE) {
483 pr_err("Invalid tag %x in flat device tree!\n", tag);
484 return -EINVAL;
485 }
486 depth++;
487 pathp = (char *)p;
488 p = ALIGN(p + strlen(pathp) + 1, 4);
489 if ((*pathp) == '/') {
490 char *lp, *np;
491 for (lp = NULL, np = pathp; *np; np++)
492 if ((*np) == '/')
493 lp = np+1;
494 if (lp != NULL)
495 pathp = lp;
496 }
497 rc = it(p, pathp, depth, data);
498 if (rc != 0)
499 break;
500 } while (1);
501
502 return rc;
503}
504
505/**
506 * of_get_flat_dt_root - find the root node in the flat blob
507 */
508unsigned long __init of_get_flat_dt_root(void)
509{
510 unsigned long p = ((unsigned long)initial_boot_params) +
511 be32_to_cpu(initial_boot_params->off_dt_struct);
512
513 while (be32_to_cpup((__be32 *)p) == OF_DT_NOP)
514 p += 4;
515 BUG_ON(be32_to_cpup((__be32 *)p) != OF_DT_BEGIN_NODE);
516 p += 4;
517 return ALIGN(p + strlen((char *)p) + 1, 4);
518}
519
520/**
521 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
522 *
523 * This function can be used within scan_flattened_dt callback to get
524 * access to properties
525 */
526void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
527 unsigned long *size)
528{
529 return of_fdt_get_property(initial_boot_params, node, name, size);
530}
531
532/**
533 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
534 * @node: node to test
535 * @compat: compatible string to compare with compatible list.
536 */
537int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
538{
539 return of_fdt_is_compatible(initial_boot_params, node, compat);
540}
541
542/**
543 * of_flat_dt_match - Return true if node matches a list of compatible values
544 */
545int __init of_flat_dt_match(unsigned long node, const char *const *compat)
546{
547 return of_fdt_match(initial_boot_params, node, compat);
548}
549
550#ifdef CONFIG_BLK_DEV_INITRD
551/**
552 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
553 * @node: reference to node containing initrd location ('chosen')
554 */
555void __init early_init_dt_check_for_initrd(unsigned long node)
556{
557 unsigned long start, end, len;
558 __be32 *prop;
559
560 pr_debug("Looking for initrd properties... ");
561
562 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
563 if (!prop)
564 return;
565 start = of_read_ulong(prop, len/4);
566
567 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
568 if (!prop)
569 return;
570 end = of_read_ulong(prop, len/4);
571
572 early_init_dt_setup_initrd_arch(start, end);
573 pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n", start, end);
574}
575#else
576inline void early_init_dt_check_for_initrd(unsigned long node)
577{
578}
579#endif /* CONFIG_BLK_DEV_INITRD */
580
581/**
582 * early_init_dt_scan_root - fetch the top level address and size cells
583 */
584int __init early_init_dt_scan_root(unsigned long node, const char *uname,
585 int depth, void *data)
586{
587 __be32 *prop;
588
589 if (depth != 0)
590 return 0;
591
592 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
593 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
594
595 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
596 if (prop)
597 dt_root_size_cells = be32_to_cpup(prop);
598 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
599
600 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
601 if (prop)
602 dt_root_addr_cells = be32_to_cpup(prop);
603 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
604
605 /* break now */
606 return 1;
607}
608
609u64 __init dt_mem_next_cell(int s, __be32 **cellp)
610{
611 __be32 *p = *cellp;
612
613 *cellp = p + s;
614 return of_read_number(p, s);
615}
616
617/**
618 * early_init_dt_scan_memory - Look for an parse memory nodes
619 */
620int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
621 int depth, void *data)
622{
623 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
624 __be32 *reg, *endp;
625 unsigned long l;
626
627 /* We are scanning "memory" nodes only */
628 if (type == NULL) {
629 /*
630 * The longtrail doesn't have a device_type on the
631 * /memory node, so look for the node called /memory@0.
632 */
633 if (depth != 1 || strcmp(uname, "memory@0") != 0)
634 return 0;
635 } else if (strcmp(type, "memory") != 0)
636 return 0;
637
638 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
639 if (reg == NULL)
640 reg = of_get_flat_dt_prop(node, "reg", &l);
641 if (reg == NULL)
642 return 0;
643
644 endp = reg + (l / sizeof(__be32));
645
646 pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
647 uname, l, reg[0], reg[1], reg[2], reg[3]);
648
649 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
650 u64 base, size;
651
652 base = dt_mem_next_cell(dt_root_addr_cells, ®);
653 size = dt_mem_next_cell(dt_root_size_cells, ®);
654
655 if (size == 0)
656 continue;
657 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
658 (unsigned long long)size);
659
660 early_init_dt_add_memory_arch(base, size);
661 }
662
663 return 0;
664}
665
666int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
667 int depth, void *data)
668{
669 unsigned long l;
670 char *p;
671
672 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
673
674 if (depth != 1 || !data ||
675 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
676 return 0;
677
678 early_init_dt_check_for_initrd(node);
679
680 /* Retrieve command line */
681 p = of_get_flat_dt_prop(node, "bootargs", &l);
682 if (p != NULL && l > 0)
683 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
684
685 /*
686 * CONFIG_CMDLINE is meant to be a default in case nothing else
687 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
688 * is set in which case we override whatever was found earlier.
689 */
690#ifdef CONFIG_CMDLINE
691#ifndef CONFIG_CMDLINE_FORCE
692 if (!((char *)data)[0])
693#endif
694 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
695#endif /* CONFIG_CMDLINE */
696
697 pr_debug("Command line is: %s\n", (char*)data);
698
699 /* break now */
700 return 1;
701}
702
703/**
704 * unflatten_device_tree - create tree of device_nodes from flat blob
705 *
706 * unflattens the device-tree passed by the firmware, creating the
707 * tree of struct device_node. It also fills the "name" and "type"
708 * pointers of the nodes so the normal device-tree walking functions
709 * can be used.
710 */
711void __init unflatten_device_tree(void)
712{
713 __unflatten_device_tree(initial_boot_params, &allnodes,
714 early_init_dt_alloc_memory_arch);
715
716 /* Get pointer to "/chosen" and "/aliasas" nodes for use everywhere */
717 of_alias_scan(early_init_dt_alloc_memory_arch);
718}
719
720#endif /* CONFIG_OF_EARLY_FLATTREE */