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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#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 */
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Functions for working with the Flattened Device Tree data format
4 *
5 * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
6 * benh@kernel.crashing.org
7 */
8
9#define pr_fmt(fmt) "OF: fdt: " fmt
10
11#include <linux/crc32.h>
12#include <linux/kernel.h>
13#include <linux/initrd.h>
14#include <linux/bootmem.h>
15#include <linux/memblock.h>
16#include <linux/mutex.h>
17#include <linux/of.h>
18#include <linux/of_fdt.h>
19#include <linux/of_reserved_mem.h>
20#include <linux/sizes.h>
21#include <linux/string.h>
22#include <linux/errno.h>
23#include <linux/slab.h>
24#include <linux/libfdt.h>
25#include <linux/debugfs.h>
26#include <linux/serial_core.h>
27#include <linux/sysfs.h>
28
29#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
30#include <asm/page.h>
31
32#include "of_private.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 __be32 *addr_prop;
50 const __be32 *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 */
92static int 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
133static bool of_fdt_device_is_available(const void *blob, unsigned long node)
134{
135 const char *status = fdt_getprop(blob, node, "status", NULL);
136
137 if (!status)
138 return true;
139
140 if (!strcmp(status, "ok") || !strcmp(status, "okay"))
141 return true;
142
143 return false;
144}
145
146/**
147 * of_fdt_match - Return true if node matches a list of compatible values
148 */
149int of_fdt_match(const void *blob, unsigned long node,
150 const char *const *compat)
151{
152 unsigned int tmp, score = 0;
153
154 if (!compat)
155 return 0;
156
157 while (*compat) {
158 tmp = of_fdt_is_compatible(blob, node, *compat);
159 if (tmp && (score == 0 || (tmp < score)))
160 score = tmp;
161 compat++;
162 }
163
164 return score;
165}
166
167static void *unflatten_dt_alloc(void **mem, unsigned long size,
168 unsigned long align)
169{
170 void *res;
171
172 *mem = PTR_ALIGN(*mem, align);
173 res = *mem;
174 *mem += size;
175
176 return res;
177}
178
179static void populate_properties(const void *blob,
180 int offset,
181 void **mem,
182 struct device_node *np,
183 const char *nodename,
184 bool dryrun)
185{
186 struct property *pp, **pprev = NULL;
187 int cur;
188 bool has_name = false;
189
190 pprev = &np->properties;
191 for (cur = fdt_first_property_offset(blob, offset);
192 cur >= 0;
193 cur = fdt_next_property_offset(blob, cur)) {
194 const __be32 *val;
195 const char *pname;
196 u32 sz;
197
198 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
199 if (!val) {
200 pr_warn("Cannot locate property at 0x%x\n", cur);
201 continue;
202 }
203
204 if (!pname) {
205 pr_warn("Cannot find property name at 0x%x\n", cur);
206 continue;
207 }
208
209 if (!strcmp(pname, "name"))
210 has_name = true;
211
212 pp = unflatten_dt_alloc(mem, sizeof(struct property),
213 __alignof__(struct property));
214 if (dryrun)
215 continue;
216
217 /* We accept flattened tree phandles either in
218 * ePAPR-style "phandle" properties, or the
219 * legacy "linux,phandle" properties. If both
220 * appear and have different values, things
221 * will get weird. Don't do that.
222 */
223 if (!strcmp(pname, "phandle") ||
224 !strcmp(pname, "linux,phandle")) {
225 if (!np->phandle)
226 np->phandle = be32_to_cpup(val);
227 }
228
229 /* And we process the "ibm,phandle" property
230 * used in pSeries dynamic device tree
231 * stuff
232 */
233 if (!strcmp(pname, "ibm,phandle"))
234 np->phandle = be32_to_cpup(val);
235
236 pp->name = (char *)pname;
237 pp->length = sz;
238 pp->value = (__be32 *)val;
239 *pprev = pp;
240 pprev = &pp->next;
241 }
242
243 /* With version 0x10 we may not have the name property,
244 * recreate it here from the unit name if absent
245 */
246 if (!has_name) {
247 const char *p = nodename, *ps = p, *pa = NULL;
248 int len;
249
250 while (*p) {
251 if ((*p) == '@')
252 pa = p;
253 else if ((*p) == '/')
254 ps = p + 1;
255 p++;
256 }
257
258 if (pa < ps)
259 pa = p;
260 len = (pa - ps) + 1;
261 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
262 __alignof__(struct property));
263 if (!dryrun) {
264 pp->name = "name";
265 pp->length = len;
266 pp->value = pp + 1;
267 *pprev = pp;
268 pprev = &pp->next;
269 memcpy(pp->value, ps, len - 1);
270 ((char *)pp->value)[len - 1] = 0;
271 pr_debug("fixed up name for %s -> %s\n",
272 nodename, (char *)pp->value);
273 }
274 }
275
276 if (!dryrun)
277 *pprev = NULL;
278}
279
280static bool populate_node(const void *blob,
281 int offset,
282 void **mem,
283 struct device_node *dad,
284 struct device_node **pnp,
285 bool dryrun)
286{
287 struct device_node *np;
288 const char *pathp;
289 unsigned int l, allocl;
290
291 pathp = fdt_get_name(blob, offset, &l);
292 if (!pathp) {
293 *pnp = NULL;
294 return false;
295 }
296
297 allocl = ++l;
298
299 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + allocl,
300 __alignof__(struct device_node));
301 if (!dryrun) {
302 char *fn;
303 of_node_init(np);
304 np->full_name = fn = ((char *)np) + sizeof(*np);
305
306 memcpy(fn, pathp, l);
307
308 if (dad != NULL) {
309 np->parent = dad;
310 np->sibling = dad->child;
311 dad->child = np;
312 }
313 }
314
315 populate_properties(blob, offset, mem, np, pathp, dryrun);
316 if (!dryrun) {
317 np->name = of_get_property(np, "name", NULL);
318 np->type = of_get_property(np, "device_type", NULL);
319
320 if (!np->name)
321 np->name = "<NULL>";
322 if (!np->type)
323 np->type = "<NULL>";
324 }
325
326 *pnp = np;
327 return true;
328}
329
330static void reverse_nodes(struct device_node *parent)
331{
332 struct device_node *child, *next;
333
334 /* In-depth first */
335 child = parent->child;
336 while (child) {
337 reverse_nodes(child);
338
339 child = child->sibling;
340 }
341
342 /* Reverse the nodes in the child list */
343 child = parent->child;
344 parent->child = NULL;
345 while (child) {
346 next = child->sibling;
347
348 child->sibling = parent->child;
349 parent->child = child;
350 child = next;
351 }
352}
353
354/**
355 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
356 * @blob: The parent device tree blob
357 * @mem: Memory chunk to use for allocating device nodes and properties
358 * @dad: Parent struct device_node
359 * @nodepp: The device_node tree created by the call
360 *
361 * It returns the size of unflattened device tree or error code
362 */
363static int unflatten_dt_nodes(const void *blob,
364 void *mem,
365 struct device_node *dad,
366 struct device_node **nodepp)
367{
368 struct device_node *root;
369 int offset = 0, depth = 0, initial_depth = 0;
370#define FDT_MAX_DEPTH 64
371 struct device_node *nps[FDT_MAX_DEPTH];
372 void *base = mem;
373 bool dryrun = !base;
374
375 if (nodepp)
376 *nodepp = NULL;
377
378 /*
379 * We're unflattening device sub-tree if @dad is valid. There are
380 * possibly multiple nodes in the first level of depth. We need
381 * set @depth to 1 to make fdt_next_node() happy as it bails
382 * immediately when negative @depth is found. Otherwise, the device
383 * nodes except the first one won't be unflattened successfully.
384 */
385 if (dad)
386 depth = initial_depth = 1;
387
388 root = dad;
389 nps[depth] = dad;
390
391 for (offset = 0;
392 offset >= 0 && depth >= initial_depth;
393 offset = fdt_next_node(blob, offset, &depth)) {
394 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
395 continue;
396
397 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
398 !of_fdt_device_is_available(blob, offset))
399 continue;
400
401 if (!populate_node(blob, offset, &mem, nps[depth],
402 &nps[depth+1], dryrun))
403 return mem - base;
404
405 if (!dryrun && nodepp && !*nodepp)
406 *nodepp = nps[depth+1];
407 if (!dryrun && !root)
408 root = nps[depth+1];
409 }
410
411 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
412 pr_err("Error %d processing FDT\n", offset);
413 return -EINVAL;
414 }
415
416 /*
417 * Reverse the child list. Some drivers assumes node order matches .dts
418 * node order
419 */
420 if (!dryrun)
421 reverse_nodes(root);
422
423 return mem - base;
424}
425
426/**
427 * __unflatten_device_tree - create tree of device_nodes from flat blob
428 *
429 * unflattens a device-tree, creating the
430 * tree of struct device_node. It also fills the "name" and "type"
431 * pointers of the nodes so the normal device-tree walking functions
432 * can be used.
433 * @blob: The blob to expand
434 * @dad: Parent device node
435 * @mynodes: The device_node tree created by the call
436 * @dt_alloc: An allocator that provides a virtual address to memory
437 * for the resulting tree
438 * @detached: if true set OF_DETACHED on @mynodes
439 *
440 * Returns NULL on failure or the memory chunk containing the unflattened
441 * device tree on success.
442 */
443void *__unflatten_device_tree(const void *blob,
444 struct device_node *dad,
445 struct device_node **mynodes,
446 void *(*dt_alloc)(u64 size, u64 align),
447 bool detached)
448{
449 int size;
450 void *mem;
451
452 pr_debug(" -> unflatten_device_tree()\n");
453
454 if (!blob) {
455 pr_debug("No device tree pointer\n");
456 return NULL;
457 }
458
459 pr_debug("Unflattening device tree:\n");
460 pr_debug("magic: %08x\n", fdt_magic(blob));
461 pr_debug("size: %08x\n", fdt_totalsize(blob));
462 pr_debug("version: %08x\n", fdt_version(blob));
463
464 if (fdt_check_header(blob)) {
465 pr_err("Invalid device tree blob header\n");
466 return NULL;
467 }
468
469 /* First pass, scan for size */
470 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
471 if (size < 0)
472 return NULL;
473
474 size = ALIGN(size, 4);
475 pr_debug(" size is %d, allocating...\n", size);
476
477 /* Allocate memory for the expanded device tree */
478 mem = dt_alloc(size + 4, __alignof__(struct device_node));
479 if (!mem)
480 return NULL;
481
482 memset(mem, 0, size);
483
484 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
485
486 pr_debug(" unflattening %p...\n", mem);
487
488 /* Second pass, do actual unflattening */
489 unflatten_dt_nodes(blob, mem, dad, mynodes);
490 if (be32_to_cpup(mem + size) != 0xdeadbeef)
491 pr_warning("End of tree marker overwritten: %08x\n",
492 be32_to_cpup(mem + size));
493
494 if (detached && mynodes) {
495 of_node_set_flag(*mynodes, OF_DETACHED);
496 pr_debug("unflattened tree is detached\n");
497 }
498
499 pr_debug(" <- unflatten_device_tree()\n");
500 return mem;
501}
502
503static void *kernel_tree_alloc(u64 size, u64 align)
504{
505 return kzalloc(size, GFP_KERNEL);
506}
507
508static DEFINE_MUTEX(of_fdt_unflatten_mutex);
509
510/**
511 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
512 * @blob: Flat device tree blob
513 * @dad: Parent device node
514 * @mynodes: The device tree created by the call
515 *
516 * unflattens the device-tree passed by the firmware, creating the
517 * tree of struct device_node. It also fills the "name" and "type"
518 * pointers of the nodes so the normal device-tree walking functions
519 * can be used.
520 *
521 * Returns NULL on failure or the memory chunk containing the unflattened
522 * device tree on success.
523 */
524void *of_fdt_unflatten_tree(const unsigned long *blob,
525 struct device_node *dad,
526 struct device_node **mynodes)
527{
528 void *mem;
529
530 mutex_lock(&of_fdt_unflatten_mutex);
531 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
532 true);
533 mutex_unlock(&of_fdt_unflatten_mutex);
534
535 return mem;
536}
537EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
538
539/* Everything below here references initial_boot_params directly. */
540int __initdata dt_root_addr_cells;
541int __initdata dt_root_size_cells;
542
543void *initial_boot_params;
544
545#ifdef CONFIG_OF_EARLY_FLATTREE
546
547static u32 of_fdt_crc32;
548
549/**
550 * res_mem_reserve_reg() - reserve all memory described in 'reg' property
551 */
552static int __init __reserved_mem_reserve_reg(unsigned long node,
553 const char *uname)
554{
555 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
556 phys_addr_t base, size;
557 int len;
558 const __be32 *prop;
559 int nomap, first = 1;
560
561 prop = of_get_flat_dt_prop(node, "reg", &len);
562 if (!prop)
563 return -ENOENT;
564
565 if (len && len % t_len != 0) {
566 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
567 uname);
568 return -EINVAL;
569 }
570
571 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
572
573 while (len >= t_len) {
574 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
575 size = dt_mem_next_cell(dt_root_size_cells, &prop);
576
577 if (size &&
578 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
579 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
580 uname, &base, (unsigned long)size / SZ_1M);
581 else
582 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
583 uname, &base, (unsigned long)size / SZ_1M);
584
585 len -= t_len;
586 if (first) {
587 fdt_reserved_mem_save_node(node, uname, base, size);
588 first = 0;
589 }
590 }
591 return 0;
592}
593
594/**
595 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
596 * in /reserved-memory matches the values supported by the current implementation,
597 * also check if ranges property has been provided
598 */
599static int __init __reserved_mem_check_root(unsigned long node)
600{
601 const __be32 *prop;
602
603 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
604 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
605 return -EINVAL;
606
607 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
608 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
609 return -EINVAL;
610
611 prop = of_get_flat_dt_prop(node, "ranges", NULL);
612 if (!prop)
613 return -EINVAL;
614 return 0;
615}
616
617/**
618 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
619 */
620static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
621 int depth, void *data)
622{
623 static int found;
624 int err;
625
626 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
627 if (__reserved_mem_check_root(node) != 0) {
628 pr_err("Reserved memory: unsupported node format, ignoring\n");
629 /* break scan */
630 return 1;
631 }
632 found = 1;
633 /* scan next node */
634 return 0;
635 } else if (!found) {
636 /* scan next node */
637 return 0;
638 } else if (found && depth < 2) {
639 /* scanning of /reserved-memory has been finished */
640 return 1;
641 }
642
643 if (!of_fdt_device_is_available(initial_boot_params, node))
644 return 0;
645
646 err = __reserved_mem_reserve_reg(node, uname);
647 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
648 fdt_reserved_mem_save_node(node, uname, 0, 0);
649
650 /* scan next node */
651 return 0;
652}
653
654/**
655 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
656 *
657 * This function grabs memory from early allocator for device exclusive use
658 * defined in device tree structures. It should be called by arch specific code
659 * once the early allocator (i.e. memblock) has been fully activated.
660 */
661void __init early_init_fdt_scan_reserved_mem(void)
662{
663 int n;
664 u64 base, size;
665
666 if (!initial_boot_params)
667 return;
668
669 /* Process header /memreserve/ fields */
670 for (n = 0; ; n++) {
671 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
672 if (!size)
673 break;
674 early_init_dt_reserve_memory_arch(base, size, 0);
675 }
676
677 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
678 fdt_init_reserved_mem();
679}
680
681/**
682 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
683 */
684void __init early_init_fdt_reserve_self(void)
685{
686 if (!initial_boot_params)
687 return;
688
689 /* Reserve the dtb region */
690 early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
691 fdt_totalsize(initial_boot_params),
692 0);
693}
694
695/**
696 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
697 * @it: callback function
698 * @data: context data pointer
699 *
700 * This function is used to scan the flattened device-tree, it is
701 * used to extract the memory information at boot before we can
702 * unflatten the tree
703 */
704int __init of_scan_flat_dt(int (*it)(unsigned long node,
705 const char *uname, int depth,
706 void *data),
707 void *data)
708{
709 const void *blob = initial_boot_params;
710 const char *pathp;
711 int offset, rc = 0, depth = -1;
712
713 if (!blob)
714 return 0;
715
716 for (offset = fdt_next_node(blob, -1, &depth);
717 offset >= 0 && depth >= 0 && !rc;
718 offset = fdt_next_node(blob, offset, &depth)) {
719
720 pathp = fdt_get_name(blob, offset, NULL);
721 if (*pathp == '/')
722 pathp = kbasename(pathp);
723 rc = it(offset, pathp, depth, data);
724 }
725 return rc;
726}
727
728/**
729 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
730 * @it: callback function
731 * @data: context data pointer
732 *
733 * This function is used to scan sub-nodes of a node.
734 */
735int __init of_scan_flat_dt_subnodes(unsigned long parent,
736 int (*it)(unsigned long node,
737 const char *uname,
738 void *data),
739 void *data)
740{
741 const void *blob = initial_boot_params;
742 int node;
743
744 fdt_for_each_subnode(node, blob, parent) {
745 const char *pathp;
746 int rc;
747
748 pathp = fdt_get_name(blob, node, NULL);
749 if (*pathp == '/')
750 pathp = kbasename(pathp);
751 rc = it(node, pathp, data);
752 if (rc)
753 return rc;
754 }
755 return 0;
756}
757
758/**
759 * of_get_flat_dt_subnode_by_name - get the subnode by given name
760 *
761 * @node: the parent node
762 * @uname: the name of subnode
763 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
764 */
765
766int of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
767{
768 return fdt_subnode_offset(initial_boot_params, node, uname);
769}
770
771/**
772 * of_get_flat_dt_root - find the root node in the flat blob
773 */
774unsigned long __init of_get_flat_dt_root(void)
775{
776 return 0;
777}
778
779/**
780 * of_get_flat_dt_size - Return the total size of the FDT
781 */
782int __init of_get_flat_dt_size(void)
783{
784 return fdt_totalsize(initial_boot_params);
785}
786
787/**
788 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
789 *
790 * This function can be used within scan_flattened_dt callback to get
791 * access to properties
792 */
793const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
794 int *size)
795{
796 return fdt_getprop(initial_boot_params, node, name, size);
797}
798
799/**
800 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
801 * @node: node to test
802 * @compat: compatible string to compare with compatible list.
803 */
804int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
805{
806 return of_fdt_is_compatible(initial_boot_params, node, compat);
807}
808
809/**
810 * of_flat_dt_match - Return true if node matches a list of compatible values
811 */
812int __init of_flat_dt_match(unsigned long node, const char *const *compat)
813{
814 return of_fdt_match(initial_boot_params, node, compat);
815}
816
817/**
818 * of_get_flat_dt_prop - Given a node in the flat blob, return the phandle
819 */
820uint32_t __init of_get_flat_dt_phandle(unsigned long node)
821{
822 return fdt_get_phandle(initial_boot_params, node);
823}
824
825struct fdt_scan_status {
826 const char *name;
827 int namelen;
828 int depth;
829 int found;
830 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
831 void *data;
832};
833
834const char * __init of_flat_dt_get_machine_name(void)
835{
836 const char *name;
837 unsigned long dt_root = of_get_flat_dt_root();
838
839 name = of_get_flat_dt_prop(dt_root, "model", NULL);
840 if (!name)
841 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
842 return name;
843}
844
845/**
846 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
847 *
848 * @default_match: A machine specific ptr to return in case of no match.
849 * @get_next_compat: callback function to return next compatible match table.
850 *
851 * Iterate through machine match tables to find the best match for the machine
852 * compatible string in the FDT.
853 */
854const void * __init of_flat_dt_match_machine(const void *default_match,
855 const void * (*get_next_compat)(const char * const**))
856{
857 const void *data = NULL;
858 const void *best_data = default_match;
859 const char *const *compat;
860 unsigned long dt_root;
861 unsigned int best_score = ~1, score = 0;
862
863 dt_root = of_get_flat_dt_root();
864 while ((data = get_next_compat(&compat))) {
865 score = of_flat_dt_match(dt_root, compat);
866 if (score > 0 && score < best_score) {
867 best_data = data;
868 best_score = score;
869 }
870 }
871 if (!best_data) {
872 const char *prop;
873 int size;
874
875 pr_err("\n unrecognized device tree list:\n[ ");
876
877 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
878 if (prop) {
879 while (size > 0) {
880 printk("'%s' ", prop);
881 size -= strlen(prop) + 1;
882 prop += strlen(prop) + 1;
883 }
884 }
885 printk("]\n\n");
886 return NULL;
887 }
888
889 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
890
891 return best_data;
892}
893
894#ifdef CONFIG_BLK_DEV_INITRD
895#ifndef __early_init_dt_declare_initrd
896static void __early_init_dt_declare_initrd(unsigned long start,
897 unsigned long end)
898{
899 initrd_start = (unsigned long)__va(start);
900 initrd_end = (unsigned long)__va(end);
901 initrd_below_start_ok = 1;
902}
903#endif
904
905/**
906 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
907 * @node: reference to node containing initrd location ('chosen')
908 */
909static void __init early_init_dt_check_for_initrd(unsigned long node)
910{
911 u64 start, end;
912 int len;
913 const __be32 *prop;
914
915 pr_debug("Looking for initrd properties... ");
916
917 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
918 if (!prop)
919 return;
920 start = of_read_number(prop, len/4);
921
922 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
923 if (!prop)
924 return;
925 end = of_read_number(prop, len/4);
926
927 __early_init_dt_declare_initrd(start, end);
928
929 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n",
930 (unsigned long long)start, (unsigned long long)end);
931}
932#else
933static inline void early_init_dt_check_for_initrd(unsigned long node)
934{
935}
936#endif /* CONFIG_BLK_DEV_INITRD */
937
938#ifdef CONFIG_SERIAL_EARLYCON
939
940int __init early_init_dt_scan_chosen_stdout(void)
941{
942 int offset;
943 const char *p, *q, *options = NULL;
944 int l;
945 const struct earlycon_id **p_match;
946 const void *fdt = initial_boot_params;
947
948 offset = fdt_path_offset(fdt, "/chosen");
949 if (offset < 0)
950 offset = fdt_path_offset(fdt, "/chosen@0");
951 if (offset < 0)
952 return -ENOENT;
953
954 p = fdt_getprop(fdt, offset, "stdout-path", &l);
955 if (!p)
956 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
957 if (!p || !l)
958 return -ENOENT;
959
960 q = strchrnul(p, ':');
961 if (*q != '\0')
962 options = q + 1;
963 l = q - p;
964
965 /* Get the node specified by stdout-path */
966 offset = fdt_path_offset_namelen(fdt, p, l);
967 if (offset < 0) {
968 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
969 return 0;
970 }
971
972 for (p_match = __earlycon_table; p_match < __earlycon_table_end;
973 p_match++) {
974 const struct earlycon_id *match = *p_match;
975
976 if (!match->compatible[0])
977 continue;
978
979 if (fdt_node_check_compatible(fdt, offset, match->compatible))
980 continue;
981
982 of_setup_earlycon(match, offset, options);
983 return 0;
984 }
985 return -ENODEV;
986}
987#endif
988
989/**
990 * early_init_dt_scan_root - fetch the top level address and size cells
991 */
992int __init early_init_dt_scan_root(unsigned long node, const char *uname,
993 int depth, void *data)
994{
995 const __be32 *prop;
996
997 if (depth != 0)
998 return 0;
999
1000 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
1001 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
1002
1003 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
1004 if (prop)
1005 dt_root_size_cells = be32_to_cpup(prop);
1006 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
1007
1008 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
1009 if (prop)
1010 dt_root_addr_cells = be32_to_cpup(prop);
1011 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
1012
1013 /* break now */
1014 return 1;
1015}
1016
1017u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
1018{
1019 const __be32 *p = *cellp;
1020
1021 *cellp = p + s;
1022 return of_read_number(p, s);
1023}
1024
1025/**
1026 * early_init_dt_scan_memory - Look for and parse memory nodes
1027 */
1028int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
1029 int depth, void *data)
1030{
1031 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1032 const __be32 *reg, *endp;
1033 int l;
1034 bool hotpluggable;
1035
1036 /* We are scanning "memory" nodes only */
1037 if (type == NULL) {
1038 /*
1039 * The longtrail doesn't have a device_type on the
1040 * /memory node, so look for the node called /memory@0.
1041 */
1042 if (!IS_ENABLED(CONFIG_PPC32) || depth != 1 || strcmp(uname, "memory@0") != 0)
1043 return 0;
1044 } else if (strcmp(type, "memory") != 0)
1045 return 0;
1046
1047 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1048 if (reg == NULL)
1049 reg = of_get_flat_dt_prop(node, "reg", &l);
1050 if (reg == NULL)
1051 return 0;
1052
1053 endp = reg + (l / sizeof(__be32));
1054 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1055
1056 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
1057
1058 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1059 u64 base, size;
1060
1061 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1062 size = dt_mem_next_cell(dt_root_size_cells, ®);
1063
1064 if (size == 0)
1065 continue;
1066 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
1067 (unsigned long long)size);
1068
1069 early_init_dt_add_memory_arch(base, size);
1070
1071 if (!hotpluggable)
1072 continue;
1073
1074 if (early_init_dt_mark_hotplug_memory_arch(base, size))
1075 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1076 base, base + size);
1077 }
1078
1079 return 0;
1080}
1081
1082int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
1083 int depth, void *data)
1084{
1085 int l;
1086 const char *p;
1087
1088 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
1089
1090 if (depth != 1 || !data ||
1091 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
1092 return 0;
1093
1094 early_init_dt_check_for_initrd(node);
1095
1096 /* Retrieve command line */
1097 p = of_get_flat_dt_prop(node, "bootargs", &l);
1098 if (p != NULL && l > 0)
1099 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
1100
1101 /*
1102 * CONFIG_CMDLINE is meant to be a default in case nothing else
1103 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1104 * is set in which case we override whatever was found earlier.
1105 */
1106#ifdef CONFIG_CMDLINE
1107#if defined(CONFIG_CMDLINE_EXTEND)
1108 strlcat(data, " ", COMMAND_LINE_SIZE);
1109 strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1110#elif defined(CONFIG_CMDLINE_FORCE)
1111 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1112#else
1113 /* No arguments from boot loader, use kernel's cmdl*/
1114 if (!((char *)data)[0])
1115 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1116#endif
1117#endif /* CONFIG_CMDLINE */
1118
1119 pr_debug("Command line is: %s\n", (char*)data);
1120
1121 /* break now */
1122 return 1;
1123}
1124
1125#ifdef CONFIG_HAVE_MEMBLOCK
1126#ifndef MIN_MEMBLOCK_ADDR
1127#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1128#endif
1129#ifndef MAX_MEMBLOCK_ADDR
1130#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1131#endif
1132
1133void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1134{
1135 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1136
1137 if (!PAGE_ALIGNED(base)) {
1138 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1139 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1140 base, base + size);
1141 return;
1142 }
1143 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1144 base = PAGE_ALIGN(base);
1145 }
1146 size &= PAGE_MASK;
1147
1148 if (base > MAX_MEMBLOCK_ADDR) {
1149 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1150 base, base + size);
1151 return;
1152 }
1153
1154 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1155 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1156 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1157 size = MAX_MEMBLOCK_ADDR - base + 1;
1158 }
1159
1160 if (base + size < phys_offset) {
1161 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1162 base, base + size);
1163 return;
1164 }
1165 if (base < phys_offset) {
1166 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1167 base, phys_offset);
1168 size -= phys_offset - base;
1169 base = phys_offset;
1170 }
1171 memblock_add(base, size);
1172}
1173
1174int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1175{
1176 return memblock_mark_hotplug(base, size);
1177}
1178
1179int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1180 phys_addr_t size, bool nomap)
1181{
1182 if (nomap)
1183 return memblock_remove(base, size);
1184 return memblock_reserve(base, size);
1185}
1186
1187#else
1188void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1189{
1190 WARN_ON(1);
1191}
1192
1193int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1194{
1195 return -ENOSYS;
1196}
1197
1198int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1199 phys_addr_t size, bool nomap)
1200{
1201 pr_err("Reserved memory not supported, ignoring range %pa - %pa%s\n",
1202 &base, &size, nomap ? " (nomap)" : "");
1203 return -ENOSYS;
1204}
1205#endif
1206
1207static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1208{
1209 return memblock_virt_alloc(size, align);
1210}
1211
1212bool __init early_init_dt_verify(void *params)
1213{
1214 if (!params)
1215 return false;
1216
1217 /* check device tree validity */
1218 if (fdt_check_header(params))
1219 return false;
1220
1221 /* Setup flat device-tree pointer */
1222 initial_boot_params = params;
1223 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1224 fdt_totalsize(initial_boot_params));
1225 return true;
1226}
1227
1228
1229void __init early_init_dt_scan_nodes(void)
1230{
1231 /* Retrieve various information from the /chosen node */
1232 of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1233
1234 /* Initialize {size,address}-cells info */
1235 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1236
1237 /* Setup memory, calling early_init_dt_add_memory_arch */
1238 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1239}
1240
1241bool __init early_init_dt_scan(void *params)
1242{
1243 bool status;
1244
1245 status = early_init_dt_verify(params);
1246 if (!status)
1247 return false;
1248
1249 early_init_dt_scan_nodes();
1250 return true;
1251}
1252
1253/**
1254 * unflatten_device_tree - create tree of device_nodes from flat blob
1255 *
1256 * unflattens the device-tree passed by the firmware, creating the
1257 * tree of struct device_node. It also fills the "name" and "type"
1258 * pointers of the nodes so the normal device-tree walking functions
1259 * can be used.
1260 */
1261void __init unflatten_device_tree(void)
1262{
1263 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1264 early_init_dt_alloc_memory_arch, false);
1265
1266 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1267 of_alias_scan(early_init_dt_alloc_memory_arch);
1268
1269 unittest_unflatten_overlay_base();
1270}
1271
1272/**
1273 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1274 *
1275 * Copies and unflattens the device-tree passed by the firmware, creating the
1276 * tree of struct device_node. It also fills the "name" and "type"
1277 * pointers of the nodes so the normal device-tree walking functions
1278 * can be used. This should only be used when the FDT memory has not been
1279 * reserved such is the case when the FDT is built-in to the kernel init
1280 * section. If the FDT memory is reserved already then unflatten_device_tree
1281 * should be used instead.
1282 */
1283void __init unflatten_and_copy_device_tree(void)
1284{
1285 int size;
1286 void *dt;
1287
1288 if (!initial_boot_params) {
1289 pr_warn("No valid device tree found, continuing without\n");
1290 return;
1291 }
1292
1293 size = fdt_totalsize(initial_boot_params);
1294 dt = early_init_dt_alloc_memory_arch(size,
1295 roundup_pow_of_two(FDT_V17_SIZE));
1296
1297 if (dt) {
1298 memcpy(dt, initial_boot_params, size);
1299 initial_boot_params = dt;
1300 }
1301 unflatten_device_tree();
1302}
1303
1304#ifdef CONFIG_SYSFS
1305static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1306 struct bin_attribute *bin_attr,
1307 char *buf, loff_t off, size_t count)
1308{
1309 memcpy(buf, initial_boot_params + off, count);
1310 return count;
1311}
1312
1313static int __init of_fdt_raw_init(void)
1314{
1315 static struct bin_attribute of_fdt_raw_attr =
1316 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1317
1318 if (!initial_boot_params)
1319 return 0;
1320
1321 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1322 fdt_totalsize(initial_boot_params))) {
1323 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1324 return 0;
1325 }
1326 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1327 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1328}
1329late_initcall(of_fdt_raw_init);
1330#endif
1331
1332#endif /* CONFIG_OF_EARLY_FLATTREE */