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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/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#ifdef CONFIG_PPC
22#include <asm/machdep.h>
23#endif /* CONFIG_PPC */
24
25#include <asm/page.h>
26
27char *of_fdt_get_string(struct boot_param_header *blob, u32 offset)
28{
29 return ((char *)blob) +
30 be32_to_cpu(blob->off_dt_strings) + offset;
31}
32
33/**
34 * of_fdt_get_property - Given a node in the given flat blob, return
35 * the property ptr
36 */
37void *of_fdt_get_property(struct boot_param_header *blob,
38 unsigned long node, const char *name,
39 unsigned long *size)
40{
41 unsigned long p = node;
42
43 do {
44 u32 tag = be32_to_cpup((__be32 *)p);
45 u32 sz, noff;
46 const char *nstr;
47
48 p += 4;
49 if (tag == OF_DT_NOP)
50 continue;
51 if (tag != OF_DT_PROP)
52 return NULL;
53
54 sz = be32_to_cpup((__be32 *)p);
55 noff = be32_to_cpup((__be32 *)(p + 4));
56 p += 8;
57 if (be32_to_cpu(blob->version) < 0x10)
58 p = ALIGN(p, sz >= 8 ? 8 : 4);
59
60 nstr = of_fdt_get_string(blob, noff);
61 if (nstr == NULL) {
62 pr_warning("Can't find property index name !\n");
63 return NULL;
64 }
65 if (strcmp(name, nstr) == 0) {
66 if (size)
67 *size = sz;
68 return (void *)p;
69 }
70 p += sz;
71 p = ALIGN(p, 4);
72 } while (1);
73}
74
75/**
76 * of_fdt_is_compatible - Return true if given node from the given blob has
77 * compat in its compatible list
78 * @blob: A device tree blob
79 * @node: node to test
80 * @compat: compatible string to compare with compatible list.
81 *
82 * On match, returns a non-zero value with smaller values returned for more
83 * specific compatible values.
84 */
85int of_fdt_is_compatible(struct boot_param_header *blob,
86 unsigned long node, const char *compat)
87{
88 const char *cp;
89 unsigned long cplen, l, score = 0;
90
91 cp = of_fdt_get_property(blob, node, "compatible", &cplen);
92 if (cp == NULL)
93 return 0;
94 while (cplen > 0) {
95 score++;
96 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
97 return score;
98 l = strlen(cp) + 1;
99 cp += l;
100 cplen -= l;
101 }
102
103 return 0;
104}
105
106/**
107 * of_fdt_match - Return true if node matches a list of compatible values
108 */
109int of_fdt_match(struct boot_param_header *blob, unsigned long node,
110 const char **compat)
111{
112 unsigned int tmp, score = 0;
113
114 if (!compat)
115 return 0;
116
117 while (*compat) {
118 tmp = of_fdt_is_compatible(blob, node, *compat);
119 if (tmp && (score == 0 || (tmp < score)))
120 score = tmp;
121 compat++;
122 }
123
124 return score;
125}
126
127static void *unflatten_dt_alloc(unsigned long *mem, unsigned long size,
128 unsigned long align)
129{
130 void *res;
131
132 *mem = ALIGN(*mem, align);
133 res = (void *)*mem;
134 *mem += size;
135
136 return res;
137}
138
139/**
140 * unflatten_dt_node - Alloc and populate a device_node from the flat tree
141 * @blob: The parent device tree blob
142 * @mem: Memory chunk to use for allocating device nodes and properties
143 * @p: pointer to node in flat tree
144 * @dad: Parent struct device_node
145 * @allnextpp: pointer to ->allnext from last allocated device_node
146 * @fpsize: Size of the node path up at the current depth.
147 */
148static unsigned long unflatten_dt_node(struct boot_param_header *blob,
149 unsigned long mem,
150 unsigned long *p,
151 struct device_node *dad,
152 struct device_node ***allnextpp,
153 unsigned long fpsize)
154{
155 struct device_node *np;
156 struct property *pp, **prev_pp = NULL;
157 char *pathp;
158 u32 tag;
159 unsigned int l, allocl;
160 int has_name = 0;
161 int new_format = 0;
162
163 tag = be32_to_cpup((__be32 *)(*p));
164 if (tag != OF_DT_BEGIN_NODE) {
165 pr_err("Weird tag at start of node: %x\n", tag);
166 return mem;
167 }
168 *p += 4;
169 pathp = (char *)*p;
170 l = allocl = strlen(pathp) + 1;
171 *p = ALIGN(*p + l, 4);
172
173 /* version 0x10 has a more compact unit name here instead of the full
174 * path. we accumulate the full path size using "fpsize", we'll rebuild
175 * it later. We detect this because the first character of the name is
176 * not '/'.
177 */
178 if ((*pathp) != '/') {
179 new_format = 1;
180 if (fpsize == 0) {
181 /* root node: special case. fpsize accounts for path
182 * plus terminating zero. root node only has '/', so
183 * fpsize should be 2, but we want to avoid the first
184 * level nodes to have two '/' so we use fpsize 1 here
185 */
186 fpsize = 1;
187 allocl = 2;
188 } else {
189 /* account for '/' and path size minus terminal 0
190 * already in 'l'
191 */
192 fpsize += l;
193 allocl = fpsize;
194 }
195 }
196
197 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
198 __alignof__(struct device_node));
199 if (allnextpp) {
200 memset(np, 0, sizeof(*np));
201 np->full_name = ((char *)np) + sizeof(struct device_node);
202 if (new_format) {
203 char *fn = np->full_name;
204 /* rebuild full path for new format */
205 if (dad && dad->parent) {
206 strcpy(fn, dad->full_name);
207#ifdef DEBUG
208 if ((strlen(fn) + l + 1) != allocl) {
209 pr_debug("%s: p: %d, l: %d, a: %d\n",
210 pathp, (int)strlen(fn),
211 l, allocl);
212 }
213#endif
214 fn += strlen(fn);
215 }
216 *(fn++) = '/';
217 memcpy(fn, pathp, l);
218 } else
219 memcpy(np->full_name, pathp, l);
220 prev_pp = &np->properties;
221 **allnextpp = np;
222 *allnextpp = &np->allnext;
223 if (dad != NULL) {
224 np->parent = dad;
225 /* we temporarily use the next field as `last_child'*/
226 if (dad->next == NULL)
227 dad->child = np;
228 else
229 dad->next->sibling = np;
230 dad->next = np;
231 }
232 kref_init(&np->kref);
233 }
234 /* process properties */
235 while (1) {
236 u32 sz, noff;
237 char *pname;
238
239 tag = be32_to_cpup((__be32 *)(*p));
240 if (tag == OF_DT_NOP) {
241 *p += 4;
242 continue;
243 }
244 if (tag != OF_DT_PROP)
245 break;
246 *p += 4;
247 sz = be32_to_cpup((__be32 *)(*p));
248 noff = be32_to_cpup((__be32 *)((*p) + 4));
249 *p += 8;
250 if (be32_to_cpu(blob->version) < 0x10)
251 *p = ALIGN(*p, sz >= 8 ? 8 : 4);
252
253 pname = of_fdt_get_string(blob, noff);
254 if (pname == NULL) {
255 pr_info("Can't find property name in list !\n");
256 break;
257 }
258 if (strcmp(pname, "name") == 0)
259 has_name = 1;
260 l = strlen(pname) + 1;
261 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
262 __alignof__(struct property));
263 if (allnextpp) {
264 /* We accept flattened tree phandles either in
265 * ePAPR-style "phandle" properties, or the
266 * legacy "linux,phandle" properties. If both
267 * appear and have different values, things
268 * will get weird. Don't do that. */
269 if ((strcmp(pname, "phandle") == 0) ||
270 (strcmp(pname, "linux,phandle") == 0)) {
271 if (np->phandle == 0)
272 np->phandle = be32_to_cpup((__be32*)*p);
273 }
274 /* And we process the "ibm,phandle" property
275 * used in pSeries dynamic device tree
276 * stuff */
277 if (strcmp(pname, "ibm,phandle") == 0)
278 np->phandle = be32_to_cpup((__be32 *)*p);
279 pp->name = pname;
280 pp->length = sz;
281 pp->value = (void *)*p;
282 *prev_pp = pp;
283 prev_pp = &pp->next;
284 }
285 *p = ALIGN((*p) + sz, 4);
286 }
287 /* with version 0x10 we may not have the name property, recreate
288 * it here from the unit name if absent
289 */
290 if (!has_name) {
291 char *p1 = pathp, *ps = pathp, *pa = NULL;
292 int sz;
293
294 while (*p1) {
295 if ((*p1) == '@')
296 pa = p1;
297 if ((*p1) == '/')
298 ps = p1 + 1;
299 p1++;
300 }
301 if (pa < ps)
302 pa = p1;
303 sz = (pa - ps) + 1;
304 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
305 __alignof__(struct property));
306 if (allnextpp) {
307 pp->name = "name";
308 pp->length = sz;
309 pp->value = pp + 1;
310 *prev_pp = pp;
311 prev_pp = &pp->next;
312 memcpy(pp->value, ps, sz - 1);
313 ((char *)pp->value)[sz - 1] = 0;
314 pr_debug("fixed up name for %s -> %s\n", pathp,
315 (char *)pp->value);
316 }
317 }
318 if (allnextpp) {
319 *prev_pp = NULL;
320 np->name = of_get_property(np, "name", NULL);
321 np->type = of_get_property(np, "device_type", NULL);
322
323 if (!np->name)
324 np->name = "<NULL>";
325 if (!np->type)
326 np->type = "<NULL>";
327 }
328 while (tag == OF_DT_BEGIN_NODE || tag == OF_DT_NOP) {
329 if (tag == OF_DT_NOP)
330 *p += 4;
331 else
332 mem = unflatten_dt_node(blob, mem, p, np, allnextpp,
333 fpsize);
334 tag = be32_to_cpup((__be32 *)(*p));
335 }
336 if (tag != OF_DT_END_NODE) {
337 pr_err("Weird tag at end of node: %x\n", tag);
338 return mem;
339 }
340 *p += 4;
341 return mem;
342}
343
344/**
345 * __unflatten_device_tree - create tree of device_nodes from flat blob
346 *
347 * unflattens a device-tree, creating the
348 * tree of struct device_node. It also fills the "name" and "type"
349 * pointers of the nodes so the normal device-tree walking functions
350 * can be used.
351 * @blob: The blob to expand
352 * @mynodes: The device_node tree created by the call
353 * @dt_alloc: An allocator that provides a virtual address to memory
354 * for the resulting tree
355 */
356static void __unflatten_device_tree(struct boot_param_header *blob,
357 struct device_node **mynodes,
358 void * (*dt_alloc)(u64 size, u64 align))
359{
360 unsigned long start, mem, size;
361 struct device_node **allnextp = mynodes;
362
363 pr_debug(" -> unflatten_device_tree()\n");
364
365 if (!blob) {
366 pr_debug("No device tree pointer\n");
367 return;
368 }
369
370 pr_debug("Unflattening device tree:\n");
371 pr_debug("magic: %08x\n", be32_to_cpu(blob->magic));
372 pr_debug("size: %08x\n", be32_to_cpu(blob->totalsize));
373 pr_debug("version: %08x\n", be32_to_cpu(blob->version));
374
375 if (be32_to_cpu(blob->magic) != OF_DT_HEADER) {
376 pr_err("Invalid device tree blob header\n");
377 return;
378 }
379
380 /* First pass, scan for size */
381 start = ((unsigned long)blob) +
382 be32_to_cpu(blob->off_dt_struct);
383 size = unflatten_dt_node(blob, 0, &start, NULL, NULL, 0);
384 size = (size | 3) + 1;
385
386 pr_debug(" size is %lx, allocating...\n", size);
387
388 /* Allocate memory for the expanded device tree */
389 mem = (unsigned long)
390 dt_alloc(size + 4, __alignof__(struct device_node));
391
392 ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef);
393
394 pr_debug(" unflattening %lx...\n", mem);
395
396 /* Second pass, do actual unflattening */
397 start = ((unsigned long)blob) +
398 be32_to_cpu(blob->off_dt_struct);
399 unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0);
400 if (be32_to_cpup((__be32 *)start) != OF_DT_END)
401 pr_warning("Weird tag at end of tree: %08x\n", *((u32 *)start));
402 if (be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeef)
403 pr_warning("End of tree marker overwritten: %08x\n",
404 be32_to_cpu(((__be32 *)mem)[size / 4]));
405 *allnextp = NULL;
406
407 pr_debug(" <- unflatten_device_tree()\n");
408}
409
410static void *kernel_tree_alloc(u64 size, u64 align)
411{
412 return kzalloc(size, GFP_KERNEL);
413}
414
415/**
416 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
417 *
418 * unflattens the device-tree passed by the firmware, creating the
419 * tree of struct device_node. It also fills the "name" and "type"
420 * pointers of the nodes so the normal device-tree walking functions
421 * can be used.
422 */
423void of_fdt_unflatten_tree(unsigned long *blob,
424 struct device_node **mynodes)
425{
426 struct boot_param_header *device_tree =
427 (struct boot_param_header *)blob;
428 __unflatten_device_tree(device_tree, mynodes, &kernel_tree_alloc);
429}
430EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
431
432/* Everything below here references initial_boot_params directly. */
433int __initdata dt_root_addr_cells;
434int __initdata dt_root_size_cells;
435
436struct boot_param_header *initial_boot_params;
437
438#ifdef CONFIG_OF_EARLY_FLATTREE
439
440/**
441 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
442 * @it: callback function
443 * @data: context data pointer
444 *
445 * This function is used to scan the flattened device-tree, it is
446 * used to extract the memory information at boot before we can
447 * unflatten the tree
448 */
449int __init of_scan_flat_dt(int (*it)(unsigned long node,
450 const char *uname, int depth,
451 void *data),
452 void *data)
453{
454 unsigned long p = ((unsigned long)initial_boot_params) +
455 be32_to_cpu(initial_boot_params->off_dt_struct);
456 int rc = 0;
457 int depth = -1;
458
459 do {
460 u32 tag = be32_to_cpup((__be32 *)p);
461 char *pathp;
462
463 p += 4;
464 if (tag == OF_DT_END_NODE) {
465 depth--;
466 continue;
467 }
468 if (tag == OF_DT_NOP)
469 continue;
470 if (tag == OF_DT_END)
471 break;
472 if (tag == OF_DT_PROP) {
473 u32 sz = be32_to_cpup((__be32 *)p);
474 p += 8;
475 if (be32_to_cpu(initial_boot_params->version) < 0x10)
476 p = ALIGN(p, sz >= 8 ? 8 : 4);
477 p += sz;
478 p = ALIGN(p, 4);
479 continue;
480 }
481 if (tag != OF_DT_BEGIN_NODE) {
482 pr_err("Invalid tag %x in flat device tree!\n", tag);
483 return -EINVAL;
484 }
485 depth++;
486 pathp = (char *)p;
487 p = ALIGN(p + strlen(pathp) + 1, 4);
488 if ((*pathp) == '/') {
489 char *lp, *np;
490 for (lp = NULL, np = pathp; *np; np++)
491 if ((*np) == '/')
492 lp = np+1;
493 if (lp != NULL)
494 pathp = lp;
495 }
496 rc = it(p, pathp, depth, data);
497 if (rc != 0)
498 break;
499 } while (1);
500
501 return rc;
502}
503
504/**
505 * of_get_flat_dt_root - find the root node in the flat blob
506 */
507unsigned long __init of_get_flat_dt_root(void)
508{
509 unsigned long p = ((unsigned long)initial_boot_params) +
510 be32_to_cpu(initial_boot_params->off_dt_struct);
511
512 while (be32_to_cpup((__be32 *)p) == OF_DT_NOP)
513 p += 4;
514 BUG_ON(be32_to_cpup((__be32 *)p) != OF_DT_BEGIN_NODE);
515 p += 4;
516 return ALIGN(p + strlen((char *)p) + 1, 4);
517}
518
519/**
520 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
521 *
522 * This function can be used within scan_flattened_dt callback to get
523 * access to properties
524 */
525void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
526 unsigned long *size)
527{
528 return of_fdt_get_property(initial_boot_params, node, name, size);
529}
530
531/**
532 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
533 * @node: node to test
534 * @compat: compatible string to compare with compatible list.
535 */
536int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
537{
538 return of_fdt_is_compatible(initial_boot_params, node, compat);
539}
540
541/**
542 * of_flat_dt_match - Return true if node matches a list of compatible values
543 */
544int __init of_flat_dt_match(unsigned long node, const char **compat)
545{
546 return of_fdt_match(initial_boot_params, node, compat);
547}
548
549#ifdef CONFIG_BLK_DEV_INITRD
550/**
551 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
552 * @node: reference to node containing initrd location ('chosen')
553 */
554void __init early_init_dt_check_for_initrd(unsigned long node)
555{
556 unsigned long start, end, len;
557 __be32 *prop;
558
559 pr_debug("Looking for initrd properties... ");
560
561 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
562 if (!prop)
563 return;
564 start = of_read_ulong(prop, len/4);
565
566 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
567 if (!prop)
568 return;
569 end = of_read_ulong(prop, len/4);
570
571 early_init_dt_setup_initrd_arch(start, end);
572 pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n", start, end);
573}
574#else
575inline void early_init_dt_check_for_initrd(unsigned long node)
576{
577}
578#endif /* CONFIG_BLK_DEV_INITRD */
579
580/**
581 * early_init_dt_scan_root - fetch the top level address and size cells
582 */
583int __init early_init_dt_scan_root(unsigned long node, const char *uname,
584 int depth, void *data)
585{
586 __be32 *prop;
587
588 if (depth != 0)
589 return 0;
590
591 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
592 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
593
594 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
595 if (prop)
596 dt_root_size_cells = be32_to_cpup(prop);
597 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
598
599 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
600 if (prop)
601 dt_root_addr_cells = be32_to_cpup(prop);
602 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
603
604 /* break now */
605 return 1;
606}
607
608u64 __init dt_mem_next_cell(int s, __be32 **cellp)
609{
610 __be32 *p = *cellp;
611
612 *cellp = p + s;
613 return of_read_number(p, s);
614}
615
616/**
617 * early_init_dt_scan_memory - Look for an parse memory nodes
618 */
619int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
620 int depth, void *data)
621{
622 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
623 __be32 *reg, *endp;
624 unsigned long l;
625
626 /* We are scanning "memory" nodes only */
627 if (type == NULL) {
628 /*
629 * The longtrail doesn't have a device_type on the
630 * /memory node, so look for the node called /memory@0.
631 */
632 if (depth != 1 || strcmp(uname, "memory@0") != 0)
633 return 0;
634 } else if (strcmp(type, "memory") != 0)
635 return 0;
636
637 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
638 if (reg == NULL)
639 reg = of_get_flat_dt_prop(node, "reg", &l);
640 if (reg == NULL)
641 return 0;
642
643 endp = reg + (l / sizeof(__be32));
644
645 pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
646 uname, l, reg[0], reg[1], reg[2], reg[3]);
647
648 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
649 u64 base, size;
650
651 base = dt_mem_next_cell(dt_root_addr_cells, ®);
652 size = dt_mem_next_cell(dt_root_size_cells, ®);
653
654 if (size == 0)
655 continue;
656 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
657 (unsigned long long)size);
658
659 early_init_dt_add_memory_arch(base, size);
660 }
661
662 return 0;
663}
664
665int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
666 int depth, void *data)
667{
668 unsigned long l;
669 char *p;
670
671 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
672
673 if (depth != 1 || !data ||
674 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
675 return 0;
676
677 early_init_dt_check_for_initrd(node);
678
679 /* Retrieve command line */
680 p = of_get_flat_dt_prop(node, "bootargs", &l);
681 if (p != NULL && l > 0)
682 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
683
684#ifdef CONFIG_CMDLINE
685#ifndef CONFIG_CMDLINE_FORCE
686 if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
687#endif
688 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
689#endif /* CONFIG_CMDLINE */
690
691 pr_debug("Command line is: %s\n", (char*)data);
692
693 /* break now */
694 return 1;
695}
696
697/**
698 * unflatten_device_tree - create tree of device_nodes from flat blob
699 *
700 * unflattens the device-tree passed by the firmware, creating the
701 * tree of struct device_node. It also fills the "name" and "type"
702 * pointers of the nodes so the normal device-tree walking functions
703 * can be used.
704 */
705void __init unflatten_device_tree(void)
706{
707 __unflatten_device_tree(initial_boot_params, &allnodes,
708 early_init_dt_alloc_memory_arch);
709
710 /* Get pointer to OF "/chosen" node for use everywhere */
711 of_chosen = of_find_node_by_path("/chosen");
712 if (of_chosen == NULL)
713 of_chosen = of_find_node_by_path("/chosen@0");
714}
715
716#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#define pr_fmt(fmt) "OF: fdt:" fmt
13
14#include <linux/crc32.h>
15#include <linux/kernel.h>
16#include <linux/initrd.h>
17#include <linux/memblock.h>
18#include <linux/mutex.h>
19#include <linux/of.h>
20#include <linux/of_fdt.h>
21#include <linux/of_reserved_mem.h>
22#include <linux/sizes.h>
23#include <linux/string.h>
24#include <linux/errno.h>
25#include <linux/slab.h>
26#include <linux/libfdt.h>
27#include <linux/debugfs.h>
28#include <linux/serial_core.h>
29#include <linux/sysfs.h>
30
31#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
32#include <asm/page.h>
33
34/*
35 * of_fdt_limit_memory - limit the number of regions in the /memory node
36 * @limit: maximum entries
37 *
38 * Adjust the flattened device tree to have at most 'limit' number of
39 * memory entries in the /memory node. This function may be called
40 * any time after initial_boot_param is set.
41 */
42void of_fdt_limit_memory(int limit)
43{
44 int memory;
45 int len;
46 const void *val;
47 int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
48 int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
49 const uint32_t *addr_prop;
50 const uint32_t *size_prop;
51 int root_offset;
52 int cell_size;
53
54 root_offset = fdt_path_offset(initial_boot_params, "/");
55 if (root_offset < 0)
56 return;
57
58 addr_prop = fdt_getprop(initial_boot_params, root_offset,
59 "#address-cells", NULL);
60 if (addr_prop)
61 nr_address_cells = fdt32_to_cpu(*addr_prop);
62
63 size_prop = fdt_getprop(initial_boot_params, root_offset,
64 "#size-cells", NULL);
65 if (size_prop)
66 nr_size_cells = fdt32_to_cpu(*size_prop);
67
68 cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
69
70 memory = fdt_path_offset(initial_boot_params, "/memory");
71 if (memory > 0) {
72 val = fdt_getprop(initial_boot_params, memory, "reg", &len);
73 if (len > limit*cell_size) {
74 len = limit*cell_size;
75 pr_debug("Limiting number of entries to %d\n", limit);
76 fdt_setprop(initial_boot_params, memory, "reg", val,
77 len);
78 }
79 }
80}
81
82/**
83 * of_fdt_is_compatible - Return true if given node from the given blob has
84 * compat in its compatible list
85 * @blob: A device tree blob
86 * @node: node to test
87 * @compat: compatible string to compare with compatible list.
88 *
89 * On match, returns a non-zero value with smaller values returned for more
90 * specific compatible values.
91 */
92int of_fdt_is_compatible(const void *blob,
93 unsigned long node, const char *compat)
94{
95 const char *cp;
96 int cplen;
97 unsigned long l, score = 0;
98
99 cp = fdt_getprop(blob, node, "compatible", &cplen);
100 if (cp == NULL)
101 return 0;
102 while (cplen > 0) {
103 score++;
104 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
105 return score;
106 l = strlen(cp) + 1;
107 cp += l;
108 cplen -= l;
109 }
110
111 return 0;
112}
113
114/**
115 * of_fdt_is_big_endian - Return true if given node needs BE MMIO accesses
116 * @blob: A device tree blob
117 * @node: node to test
118 *
119 * Returns true if the node has a "big-endian" property, or if the kernel
120 * was compiled for BE *and* the node has a "native-endian" property.
121 * Returns false otherwise.
122 */
123bool of_fdt_is_big_endian(const void *blob, unsigned long node)
124{
125 if (fdt_getprop(blob, node, "big-endian", NULL))
126 return true;
127 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
128 fdt_getprop(blob, node, "native-endian", NULL))
129 return true;
130 return false;
131}
132
133/**
134 * of_fdt_match - Return true if node matches a list of compatible values
135 */
136int of_fdt_match(const void *blob, unsigned long node,
137 const char *const *compat)
138{
139 unsigned int tmp, score = 0;
140
141 if (!compat)
142 return 0;
143
144 while (*compat) {
145 tmp = of_fdt_is_compatible(blob, node, *compat);
146 if (tmp && (score == 0 || (tmp < score)))
147 score = tmp;
148 compat++;
149 }
150
151 return score;
152}
153
154static void *unflatten_dt_alloc(void **mem, unsigned long size,
155 unsigned long align)
156{
157 void *res;
158
159 *mem = PTR_ALIGN(*mem, align);
160 res = *mem;
161 *mem += size;
162
163 return res;
164}
165
166static void populate_properties(const void *blob,
167 int offset,
168 void **mem,
169 struct device_node *np,
170 const char *nodename,
171 bool dryrun)
172{
173 struct property *pp, **pprev = NULL;
174 int cur;
175 bool has_name = false;
176
177 pprev = &np->properties;
178 for (cur = fdt_first_property_offset(blob, offset);
179 cur >= 0;
180 cur = fdt_next_property_offset(blob, cur)) {
181 const __be32 *val;
182 const char *pname;
183 u32 sz;
184
185 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
186 if (!val) {
187 pr_warn("Cannot locate property at 0x%x\n", cur);
188 continue;
189 }
190
191 if (!pname) {
192 pr_warn("Cannot find property name at 0x%x\n", cur);
193 continue;
194 }
195
196 if (!strcmp(pname, "name"))
197 has_name = true;
198
199 pp = unflatten_dt_alloc(mem, sizeof(struct property),
200 __alignof__(struct property));
201 if (dryrun)
202 continue;
203
204 /* We accept flattened tree phandles either in
205 * ePAPR-style "phandle" properties, or the
206 * legacy "linux,phandle" properties. If both
207 * appear and have different values, things
208 * will get weird. Don't do that.
209 */
210 if (!strcmp(pname, "phandle") ||
211 !strcmp(pname, "linux,phandle")) {
212 if (!np->phandle)
213 np->phandle = be32_to_cpup(val);
214 }
215
216 /* And we process the "ibm,phandle" property
217 * used in pSeries dynamic device tree
218 * stuff
219 */
220 if (!strcmp(pname, "ibm,phandle"))
221 np->phandle = be32_to_cpup(val);
222
223 pp->name = (char *)pname;
224 pp->length = sz;
225 pp->value = (__be32 *)val;
226 *pprev = pp;
227 pprev = &pp->next;
228 }
229
230 /* With version 0x10 we may not have the name property,
231 * recreate it here from the unit name if absent
232 */
233 if (!has_name) {
234 const char *p = nodename, *ps = p, *pa = NULL;
235 int len;
236
237 while (*p) {
238 if ((*p) == '@')
239 pa = p;
240 else if ((*p) == '/')
241 ps = p + 1;
242 p++;
243 }
244
245 if (pa < ps)
246 pa = p;
247 len = (pa - ps) + 1;
248 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
249 __alignof__(struct property));
250 if (!dryrun) {
251 pp->name = "name";
252 pp->length = len;
253 pp->value = pp + 1;
254 *pprev = pp;
255 pprev = &pp->next;
256 memcpy(pp->value, ps, len - 1);
257 ((char *)pp->value)[len - 1] = 0;
258 pr_debug("fixed up name for %s -> %s\n",
259 nodename, (char *)pp->value);
260 }
261 }
262
263 if (!dryrun)
264 *pprev = NULL;
265}
266
267static unsigned int populate_node(const void *blob,
268 int offset,
269 void **mem,
270 struct device_node *dad,
271 unsigned int fpsize,
272 struct device_node **pnp,
273 bool dryrun)
274{
275 struct device_node *np;
276 const char *pathp;
277 unsigned int l, allocl;
278 int new_format = 0;
279
280 pathp = fdt_get_name(blob, offset, &l);
281 if (!pathp) {
282 *pnp = NULL;
283 return 0;
284 }
285
286 allocl = ++l;
287
288 /* version 0x10 has a more compact unit name here instead of the full
289 * path. we accumulate the full path size using "fpsize", we'll rebuild
290 * it later. We detect this because the first character of the name is
291 * not '/'.
292 */
293 if ((*pathp) != '/') {
294 new_format = 1;
295 if (fpsize == 0) {
296 /* root node: special case. fpsize accounts for path
297 * plus terminating zero. root node only has '/', so
298 * fpsize should be 2, but we want to avoid the first
299 * level nodes to have two '/' so we use fpsize 1 here
300 */
301 fpsize = 1;
302 allocl = 2;
303 l = 1;
304 pathp = "";
305 } else {
306 /* account for '/' and path size minus terminal 0
307 * already in 'l'
308 */
309 fpsize += l;
310 allocl = fpsize;
311 }
312 }
313
314 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + allocl,
315 __alignof__(struct device_node));
316 if (!dryrun) {
317 char *fn;
318 of_node_init(np);
319 np->full_name = fn = ((char *)np) + sizeof(*np);
320 if (new_format) {
321 /* rebuild full path for new format */
322 if (dad && dad->parent) {
323 strcpy(fn, dad->full_name);
324#ifdef DEBUG
325 if ((strlen(fn) + l + 1) != allocl) {
326 pr_debug("%s: p: %d, l: %d, a: %d\n",
327 pathp, (int)strlen(fn),
328 l, allocl);
329 }
330#endif
331 fn += strlen(fn);
332 }
333 *(fn++) = '/';
334 }
335 memcpy(fn, pathp, l);
336
337 if (dad != NULL) {
338 np->parent = dad;
339 np->sibling = dad->child;
340 dad->child = np;
341 }
342 }
343
344 populate_properties(blob, offset, mem, np, pathp, dryrun);
345 if (!dryrun) {
346 np->name = of_get_property(np, "name", NULL);
347 np->type = of_get_property(np, "device_type", NULL);
348
349 if (!np->name)
350 np->name = "<NULL>";
351 if (!np->type)
352 np->type = "<NULL>";
353 }
354
355 *pnp = np;
356 return fpsize;
357}
358
359static void reverse_nodes(struct device_node *parent)
360{
361 struct device_node *child, *next;
362
363 /* In-depth first */
364 child = parent->child;
365 while (child) {
366 reverse_nodes(child);
367
368 child = child->sibling;
369 }
370
371 /* Reverse the nodes in the child list */
372 child = parent->child;
373 parent->child = NULL;
374 while (child) {
375 next = child->sibling;
376
377 child->sibling = parent->child;
378 parent->child = child;
379 child = next;
380 }
381}
382
383/**
384 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
385 * @blob: The parent device tree blob
386 * @mem: Memory chunk to use for allocating device nodes and properties
387 * @dad: Parent struct device_node
388 * @nodepp: The device_node tree created by the call
389 *
390 * It returns the size of unflattened device tree or error code
391 */
392static int unflatten_dt_nodes(const void *blob,
393 void *mem,
394 struct device_node *dad,
395 struct device_node **nodepp)
396{
397 struct device_node *root;
398 int offset = 0, depth = 0, initial_depth = 0;
399#define FDT_MAX_DEPTH 64
400 unsigned int fpsizes[FDT_MAX_DEPTH];
401 struct device_node *nps[FDT_MAX_DEPTH];
402 void *base = mem;
403 bool dryrun = !base;
404
405 if (nodepp)
406 *nodepp = NULL;
407
408 /*
409 * We're unflattening device sub-tree if @dad is valid. There are
410 * possibly multiple nodes in the first level of depth. We need
411 * set @depth to 1 to make fdt_next_node() happy as it bails
412 * immediately when negative @depth is found. Otherwise, the device
413 * nodes except the first one won't be unflattened successfully.
414 */
415 if (dad)
416 depth = initial_depth = 1;
417
418 root = dad;
419 fpsizes[depth] = dad ? strlen(of_node_full_name(dad)) : 0;
420 nps[depth] = dad;
421
422 for (offset = 0;
423 offset >= 0 && depth >= initial_depth;
424 offset = fdt_next_node(blob, offset, &depth)) {
425 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
426 continue;
427
428 fpsizes[depth+1] = populate_node(blob, offset, &mem,
429 nps[depth],
430 fpsizes[depth],
431 &nps[depth+1], dryrun);
432 if (!fpsizes[depth+1])
433 return mem - base;
434
435 if (!dryrun && nodepp && !*nodepp)
436 *nodepp = nps[depth+1];
437 if (!dryrun && !root)
438 root = nps[depth+1];
439 }
440
441 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
442 pr_err("Error %d processing FDT\n", offset);
443 return -EINVAL;
444 }
445
446 /*
447 * Reverse the child list. Some drivers assumes node order matches .dts
448 * node order
449 */
450 if (!dryrun)
451 reverse_nodes(root);
452
453 return mem - base;
454}
455
456/**
457 * __unflatten_device_tree - create tree of device_nodes from flat blob
458 *
459 * unflattens a device-tree, creating the
460 * tree of struct device_node. It also fills the "name" and "type"
461 * pointers of the nodes so the normal device-tree walking functions
462 * can be used.
463 * @blob: The blob to expand
464 * @dad: Parent device node
465 * @mynodes: The device_node tree created by the call
466 * @dt_alloc: An allocator that provides a virtual address to memory
467 * for the resulting tree
468 *
469 * Returns NULL on failure or the memory chunk containing the unflattened
470 * device tree on success.
471 */
472static void *__unflatten_device_tree(const void *blob,
473 struct device_node *dad,
474 struct device_node **mynodes,
475 void *(*dt_alloc)(u64 size, u64 align),
476 bool detached)
477{
478 int size;
479 void *mem;
480
481 pr_debug(" -> unflatten_device_tree()\n");
482
483 if (!blob) {
484 pr_debug("No device tree pointer\n");
485 return NULL;
486 }
487
488 pr_debug("Unflattening device tree:\n");
489 pr_debug("magic: %08x\n", fdt_magic(blob));
490 pr_debug("size: %08x\n", fdt_totalsize(blob));
491 pr_debug("version: %08x\n", fdt_version(blob));
492
493 if (fdt_check_header(blob)) {
494 pr_err("Invalid device tree blob header\n");
495 return NULL;
496 }
497
498 /* First pass, scan for size */
499 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
500 if (size < 0)
501 return NULL;
502
503 size = ALIGN(size, 4);
504 pr_debug(" size is %d, allocating...\n", size);
505
506 /* Allocate memory for the expanded device tree */
507 mem = dt_alloc(size + 4, __alignof__(struct device_node));
508 memset(mem, 0, size);
509
510 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
511
512 pr_debug(" unflattening %p...\n", mem);
513
514 /* Second pass, do actual unflattening */
515 unflatten_dt_nodes(blob, mem, dad, mynodes);
516 if (be32_to_cpup(mem + size) != 0xdeadbeef)
517 pr_warning("End of tree marker overwritten: %08x\n",
518 be32_to_cpup(mem + size));
519
520 if (detached && mynodes) {
521 of_node_set_flag(*mynodes, OF_DETACHED);
522 pr_debug("unflattened tree is detached\n");
523 }
524
525 pr_debug(" <- unflatten_device_tree()\n");
526 return mem;
527}
528
529static void *kernel_tree_alloc(u64 size, u64 align)
530{
531 return kzalloc(size, GFP_KERNEL);
532}
533
534static DEFINE_MUTEX(of_fdt_unflatten_mutex);
535
536/**
537 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
538 * @blob: Flat device tree blob
539 * @dad: Parent device node
540 * @mynodes: The device tree created by the call
541 *
542 * unflattens the device-tree passed by the firmware, creating the
543 * tree of struct device_node. It also fills the "name" and "type"
544 * pointers of the nodes so the normal device-tree walking functions
545 * can be used.
546 *
547 * Returns NULL on failure or the memory chunk containing the unflattened
548 * device tree on success.
549 */
550void *of_fdt_unflatten_tree(const unsigned long *blob,
551 struct device_node *dad,
552 struct device_node **mynodes)
553{
554 void *mem;
555
556 mutex_lock(&of_fdt_unflatten_mutex);
557 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
558 true);
559 mutex_unlock(&of_fdt_unflatten_mutex);
560
561 return mem;
562}
563EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
564
565/* Everything below here references initial_boot_params directly. */
566int __initdata dt_root_addr_cells;
567int __initdata dt_root_size_cells;
568
569void *initial_boot_params;
570
571#ifdef CONFIG_OF_EARLY_FLATTREE
572
573static u32 of_fdt_crc32;
574
575/**
576 * res_mem_reserve_reg() - reserve all memory described in 'reg' property
577 */
578static int __init __reserved_mem_reserve_reg(unsigned long node,
579 const char *uname)
580{
581 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
582 phys_addr_t base, size;
583 int len;
584 const __be32 *prop;
585 int nomap, first = 1;
586
587 prop = of_get_flat_dt_prop(node, "reg", &len);
588 if (!prop)
589 return -ENOENT;
590
591 if (len && len % t_len != 0) {
592 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
593 uname);
594 return -EINVAL;
595 }
596
597 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
598
599 while (len >= t_len) {
600 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
601 size = dt_mem_next_cell(dt_root_size_cells, &prop);
602
603 if (size &&
604 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
605 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
606 uname, &base, (unsigned long)size / SZ_1M);
607 else
608 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
609 uname, &base, (unsigned long)size / SZ_1M);
610
611 len -= t_len;
612 if (first) {
613 fdt_reserved_mem_save_node(node, uname, base, size);
614 first = 0;
615 }
616 }
617 return 0;
618}
619
620/**
621 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
622 * in /reserved-memory matches the values supported by the current implementation,
623 * also check if ranges property has been provided
624 */
625static int __init __reserved_mem_check_root(unsigned long node)
626{
627 const __be32 *prop;
628
629 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
630 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
631 return -EINVAL;
632
633 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
634 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
635 return -EINVAL;
636
637 prop = of_get_flat_dt_prop(node, "ranges", NULL);
638 if (!prop)
639 return -EINVAL;
640 return 0;
641}
642
643/**
644 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
645 */
646static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
647 int depth, void *data)
648{
649 static int found;
650 const char *status;
651 int err;
652
653 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
654 if (__reserved_mem_check_root(node) != 0) {
655 pr_err("Reserved memory: unsupported node format, ignoring\n");
656 /* break scan */
657 return 1;
658 }
659 found = 1;
660 /* scan next node */
661 return 0;
662 } else if (!found) {
663 /* scan next node */
664 return 0;
665 } else if (found && depth < 2) {
666 /* scanning of /reserved-memory has been finished */
667 return 1;
668 }
669
670 status = of_get_flat_dt_prop(node, "status", NULL);
671 if (status && strcmp(status, "okay") != 0 && strcmp(status, "ok") != 0)
672 return 0;
673
674 err = __reserved_mem_reserve_reg(node, uname);
675 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
676 fdt_reserved_mem_save_node(node, uname, 0, 0);
677
678 /* scan next node */
679 return 0;
680}
681
682/**
683 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
684 *
685 * This function grabs memory from early allocator for device exclusive use
686 * defined in device tree structures. It should be called by arch specific code
687 * once the early allocator (i.e. memblock) has been fully activated.
688 */
689void __init early_init_fdt_scan_reserved_mem(void)
690{
691 int n;
692 u64 base, size;
693
694 if (!initial_boot_params)
695 return;
696
697 /* Process header /memreserve/ fields */
698 for (n = 0; ; n++) {
699 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
700 if (!size)
701 break;
702 early_init_dt_reserve_memory_arch(base, size, 0);
703 }
704
705 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
706 fdt_init_reserved_mem();
707}
708
709/**
710 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
711 */
712void __init early_init_fdt_reserve_self(void)
713{
714 if (!initial_boot_params)
715 return;
716
717 /* Reserve the dtb region */
718 early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
719 fdt_totalsize(initial_boot_params),
720 0);
721}
722
723/**
724 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
725 * @it: callback function
726 * @data: context data pointer
727 *
728 * This function is used to scan the flattened device-tree, it is
729 * used to extract the memory information at boot before we can
730 * unflatten the tree
731 */
732int __init of_scan_flat_dt(int (*it)(unsigned long node,
733 const char *uname, int depth,
734 void *data),
735 void *data)
736{
737 const void *blob = initial_boot_params;
738 const char *pathp;
739 int offset, rc = 0, depth = -1;
740
741 for (offset = fdt_next_node(blob, -1, &depth);
742 offset >= 0 && depth >= 0 && !rc;
743 offset = fdt_next_node(blob, offset, &depth)) {
744
745 pathp = fdt_get_name(blob, offset, NULL);
746 if (*pathp == '/')
747 pathp = kbasename(pathp);
748 rc = it(offset, pathp, depth, data);
749 }
750 return rc;
751}
752
753/**
754 * of_get_flat_dt_subnode_by_name - get the subnode by given name
755 *
756 * @node: the parent node
757 * @uname: the name of subnode
758 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
759 */
760
761int of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
762{
763 return fdt_subnode_offset(initial_boot_params, node, uname);
764}
765
766/**
767 * of_get_flat_dt_root - find the root node in the flat blob
768 */
769unsigned long __init of_get_flat_dt_root(void)
770{
771 return 0;
772}
773
774/**
775 * of_get_flat_dt_size - Return the total size of the FDT
776 */
777int __init of_get_flat_dt_size(void)
778{
779 return fdt_totalsize(initial_boot_params);
780}
781
782/**
783 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
784 *
785 * This function can be used within scan_flattened_dt callback to get
786 * access to properties
787 */
788const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
789 int *size)
790{
791 return fdt_getprop(initial_boot_params, node, name, size);
792}
793
794/**
795 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
796 * @node: node to test
797 * @compat: compatible string to compare with compatible list.
798 */
799int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
800{
801 return of_fdt_is_compatible(initial_boot_params, node, compat);
802}
803
804/**
805 * of_flat_dt_match - Return true if node matches a list of compatible values
806 */
807int __init of_flat_dt_match(unsigned long node, const char *const *compat)
808{
809 return of_fdt_match(initial_boot_params, node, compat);
810}
811
812struct fdt_scan_status {
813 const char *name;
814 int namelen;
815 int depth;
816 int found;
817 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
818 void *data;
819};
820
821const char * __init of_flat_dt_get_machine_name(void)
822{
823 const char *name;
824 unsigned long dt_root = of_get_flat_dt_root();
825
826 name = of_get_flat_dt_prop(dt_root, "model", NULL);
827 if (!name)
828 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
829 return name;
830}
831
832/**
833 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
834 *
835 * @default_match: A machine specific ptr to return in case of no match.
836 * @get_next_compat: callback function to return next compatible match table.
837 *
838 * Iterate through machine match tables to find the best match for the machine
839 * compatible string in the FDT.
840 */
841const void * __init of_flat_dt_match_machine(const void *default_match,
842 const void * (*get_next_compat)(const char * const**))
843{
844 const void *data = NULL;
845 const void *best_data = default_match;
846 const char *const *compat;
847 unsigned long dt_root;
848 unsigned int best_score = ~1, score = 0;
849
850 dt_root = of_get_flat_dt_root();
851 while ((data = get_next_compat(&compat))) {
852 score = of_flat_dt_match(dt_root, compat);
853 if (score > 0 && score < best_score) {
854 best_data = data;
855 best_score = score;
856 }
857 }
858 if (!best_data) {
859 const char *prop;
860 int size;
861
862 pr_err("\n unrecognized device tree list:\n[ ");
863
864 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
865 if (prop) {
866 while (size > 0) {
867 printk("'%s' ", prop);
868 size -= strlen(prop) + 1;
869 prop += strlen(prop) + 1;
870 }
871 }
872 printk("]\n\n");
873 return NULL;
874 }
875
876 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
877
878 return best_data;
879}
880
881#ifdef CONFIG_BLK_DEV_INITRD
882#ifndef __early_init_dt_declare_initrd
883static void __early_init_dt_declare_initrd(unsigned long start,
884 unsigned long end)
885{
886 initrd_start = (unsigned long)__va(start);
887 initrd_end = (unsigned long)__va(end);
888 initrd_below_start_ok = 1;
889}
890#endif
891
892/**
893 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
894 * @node: reference to node containing initrd location ('chosen')
895 */
896static void __init early_init_dt_check_for_initrd(unsigned long node)
897{
898 u64 start, end;
899 int len;
900 const __be32 *prop;
901
902 pr_debug("Looking for initrd properties... ");
903
904 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
905 if (!prop)
906 return;
907 start = of_read_number(prop, len/4);
908
909 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
910 if (!prop)
911 return;
912 end = of_read_number(prop, len/4);
913
914 __early_init_dt_declare_initrd(start, end);
915
916 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n",
917 (unsigned long long)start, (unsigned long long)end);
918}
919#else
920static inline void early_init_dt_check_for_initrd(unsigned long node)
921{
922}
923#endif /* CONFIG_BLK_DEV_INITRD */
924
925#ifdef CONFIG_SERIAL_EARLYCON
926
927int __init early_init_dt_scan_chosen_stdout(void)
928{
929 int offset;
930 const char *p, *q, *options = NULL;
931 int l;
932 const struct earlycon_id *match;
933 const void *fdt = initial_boot_params;
934
935 offset = fdt_path_offset(fdt, "/chosen");
936 if (offset < 0)
937 offset = fdt_path_offset(fdt, "/chosen@0");
938 if (offset < 0)
939 return -ENOENT;
940
941 p = fdt_getprop(fdt, offset, "stdout-path", &l);
942 if (!p)
943 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
944 if (!p || !l)
945 return -ENOENT;
946
947 q = strchrnul(p, ':');
948 if (*q != '\0')
949 options = q + 1;
950 l = q - p;
951
952 /* Get the node specified by stdout-path */
953 offset = fdt_path_offset_namelen(fdt, p, l);
954 if (offset < 0) {
955 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
956 return 0;
957 }
958
959 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
960 if (!match->compatible[0])
961 continue;
962
963 if (fdt_node_check_compatible(fdt, offset, match->compatible))
964 continue;
965
966 of_setup_earlycon(match, offset, options);
967 return 0;
968 }
969 return -ENODEV;
970}
971#endif
972
973/**
974 * early_init_dt_scan_root - fetch the top level address and size cells
975 */
976int __init early_init_dt_scan_root(unsigned long node, const char *uname,
977 int depth, void *data)
978{
979 const __be32 *prop;
980
981 if (depth != 0)
982 return 0;
983
984 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
985 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
986
987 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
988 if (prop)
989 dt_root_size_cells = be32_to_cpup(prop);
990 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
991
992 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
993 if (prop)
994 dt_root_addr_cells = be32_to_cpup(prop);
995 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
996
997 /* break now */
998 return 1;
999}
1000
1001u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
1002{
1003 const __be32 *p = *cellp;
1004
1005 *cellp = p + s;
1006 return of_read_number(p, s);
1007}
1008
1009/**
1010 * early_init_dt_scan_memory - Look for an parse memory nodes
1011 */
1012int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
1013 int depth, void *data)
1014{
1015 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1016 const __be32 *reg, *endp;
1017 int l;
1018 bool hotpluggable;
1019
1020 /* We are scanning "memory" nodes only */
1021 if (type == NULL) {
1022 /*
1023 * The longtrail doesn't have a device_type on the
1024 * /memory node, so look for the node called /memory@0.
1025 */
1026 if (!IS_ENABLED(CONFIG_PPC32) || depth != 1 || strcmp(uname, "memory@0") != 0)
1027 return 0;
1028 } else if (strcmp(type, "memory") != 0)
1029 return 0;
1030
1031 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1032 if (reg == NULL)
1033 reg = of_get_flat_dt_prop(node, "reg", &l);
1034 if (reg == NULL)
1035 return 0;
1036
1037 endp = reg + (l / sizeof(__be32));
1038 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1039
1040 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
1041
1042 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1043 u64 base, size;
1044
1045 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1046 size = dt_mem_next_cell(dt_root_size_cells, ®);
1047
1048 if (size == 0)
1049 continue;
1050 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
1051 (unsigned long long)size);
1052
1053 early_init_dt_add_memory_arch(base, size);
1054
1055 if (!hotpluggable)
1056 continue;
1057
1058 if (early_init_dt_mark_hotplug_memory_arch(base, size))
1059 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1060 base, base + size);
1061 }
1062
1063 return 0;
1064}
1065
1066int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
1067 int depth, void *data)
1068{
1069 int l;
1070 const char *p;
1071
1072 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
1073
1074 if (depth != 1 || !data ||
1075 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
1076 return 0;
1077
1078 early_init_dt_check_for_initrd(node);
1079
1080 /* Retrieve command line */
1081 p = of_get_flat_dt_prop(node, "bootargs", &l);
1082 if (p != NULL && l > 0)
1083 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
1084
1085 /*
1086 * CONFIG_CMDLINE is meant to be a default in case nothing else
1087 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1088 * is set in which case we override whatever was found earlier.
1089 */
1090#ifdef CONFIG_CMDLINE
1091#if defined(CONFIG_CMDLINE_EXTEND)
1092 strlcat(data, " ", COMMAND_LINE_SIZE);
1093 strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1094#elif defined(CONFIG_CMDLINE_FORCE)
1095 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1096#else
1097 /* No arguments from boot loader, use kernel's cmdl*/
1098 if (!((char *)data)[0])
1099 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1100#endif
1101#endif /* CONFIG_CMDLINE */
1102
1103 pr_debug("Command line is: %s\n", (char*)data);
1104
1105 /* break now */
1106 return 1;
1107}
1108
1109#ifdef CONFIG_HAVE_MEMBLOCK
1110#ifndef MIN_MEMBLOCK_ADDR
1111#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1112#endif
1113#ifndef MAX_MEMBLOCK_ADDR
1114#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1115#endif
1116
1117void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1118{
1119 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1120
1121 if (!PAGE_ALIGNED(base)) {
1122 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1123 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1124 base, base + size);
1125 return;
1126 }
1127 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1128 base = PAGE_ALIGN(base);
1129 }
1130 size &= PAGE_MASK;
1131
1132 if (base > MAX_MEMBLOCK_ADDR) {
1133 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1134 base, base + size);
1135 return;
1136 }
1137
1138 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1139 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1140 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1141 size = MAX_MEMBLOCK_ADDR - base + 1;
1142 }
1143
1144 if (base + size < phys_offset) {
1145 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1146 base, base + size);
1147 return;
1148 }
1149 if (base < phys_offset) {
1150 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1151 base, phys_offset);
1152 size -= phys_offset - base;
1153 base = phys_offset;
1154 }
1155 memblock_add(base, size);
1156}
1157
1158int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1159{
1160 return memblock_mark_hotplug(base, size);
1161}
1162
1163int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1164 phys_addr_t size, bool nomap)
1165{
1166 if (nomap)
1167 return memblock_remove(base, size);
1168 return memblock_reserve(base, size);
1169}
1170
1171/*
1172 * called from unflatten_device_tree() to bootstrap devicetree itself
1173 * Architectures can override this definition if memblock isn't used
1174 */
1175void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
1176{
1177 return __va(memblock_alloc(size, align));
1178}
1179#else
1180void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1181{
1182 WARN_ON(1);
1183}
1184
1185int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1186{
1187 return -ENOSYS;
1188}
1189
1190int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1191 phys_addr_t size, bool nomap)
1192{
1193 pr_err("Reserved memory not supported, ignoring range %pa - %pa%s\n",
1194 &base, &size, nomap ? " (nomap)" : "");
1195 return -ENOSYS;
1196}
1197
1198void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
1199{
1200 WARN_ON(1);
1201 return NULL;
1202}
1203#endif
1204
1205bool __init early_init_dt_verify(void *params)
1206{
1207 if (!params)
1208 return false;
1209
1210 /* check device tree validity */
1211 if (fdt_check_header(params))
1212 return false;
1213
1214 /* Setup flat device-tree pointer */
1215 initial_boot_params = params;
1216 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1217 fdt_totalsize(initial_boot_params));
1218 return true;
1219}
1220
1221
1222void __init early_init_dt_scan_nodes(void)
1223{
1224 /* Retrieve various information from the /chosen node */
1225 of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1226
1227 /* Initialize {size,address}-cells info */
1228 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1229
1230 /* Setup memory, calling early_init_dt_add_memory_arch */
1231 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1232}
1233
1234bool __init early_init_dt_scan(void *params)
1235{
1236 bool status;
1237
1238 status = early_init_dt_verify(params);
1239 if (!status)
1240 return false;
1241
1242 early_init_dt_scan_nodes();
1243 return true;
1244}
1245
1246/**
1247 * unflatten_device_tree - create tree of device_nodes from flat blob
1248 *
1249 * unflattens the device-tree passed by the firmware, creating the
1250 * tree of struct device_node. It also fills the "name" and "type"
1251 * pointers of the nodes so the normal device-tree walking functions
1252 * can be used.
1253 */
1254void __init unflatten_device_tree(void)
1255{
1256 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1257 early_init_dt_alloc_memory_arch, false);
1258
1259 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1260 of_alias_scan(early_init_dt_alloc_memory_arch);
1261}
1262
1263/**
1264 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1265 *
1266 * Copies and unflattens the device-tree passed by the firmware, creating the
1267 * tree of struct device_node. It also fills the "name" and "type"
1268 * pointers of the nodes so the normal device-tree walking functions
1269 * can be used. This should only be used when the FDT memory has not been
1270 * reserved such is the case when the FDT is built-in to the kernel init
1271 * section. If the FDT memory is reserved already then unflatten_device_tree
1272 * should be used instead.
1273 */
1274void __init unflatten_and_copy_device_tree(void)
1275{
1276 int size;
1277 void *dt;
1278
1279 if (!initial_boot_params) {
1280 pr_warn("No valid device tree found, continuing without\n");
1281 return;
1282 }
1283
1284 size = fdt_totalsize(initial_boot_params);
1285 dt = early_init_dt_alloc_memory_arch(size,
1286 roundup_pow_of_two(FDT_V17_SIZE));
1287
1288 if (dt) {
1289 memcpy(dt, initial_boot_params, size);
1290 initial_boot_params = dt;
1291 }
1292 unflatten_device_tree();
1293}
1294
1295#ifdef CONFIG_SYSFS
1296static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1297 struct bin_attribute *bin_attr,
1298 char *buf, loff_t off, size_t count)
1299{
1300 memcpy(buf, initial_boot_params + off, count);
1301 return count;
1302}
1303
1304static int __init of_fdt_raw_init(void)
1305{
1306 static struct bin_attribute of_fdt_raw_attr =
1307 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1308
1309 if (!initial_boot_params)
1310 return 0;
1311
1312 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1313 fdt_totalsize(initial_boot_params))) {
1314 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1315 return 0;
1316 }
1317 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1318 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1319}
1320late_initcall(of_fdt_raw_init);
1321#endif
1322
1323#endif /* CONFIG_OF_EARLY_FLATTREE */