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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/crash_dump.h>
12#include <linux/crc32.h>
13#include <linux/kernel.h>
14#include <linux/initrd.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/sizes.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/slab.h>
23#include <linux/libfdt.h>
24#include <linux/debugfs.h>
25#include <linux/serial_core.h>
26#include <linux/sysfs.h>
27#include <linux/random.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 * __dtb_empty_root_begin[] and __dtb_empty_root_end[] magically created by
36 * cmd_wrap_S_dtb in scripts/Makefile.dtbs
37 */
38extern uint8_t __dtb_empty_root_begin[];
39extern uint8_t __dtb_empty_root_end[];
40
41/*
42 * of_fdt_limit_memory - limit the number of regions in the /memory node
43 * @limit: maximum entries
44 *
45 * Adjust the flattened device tree to have at most 'limit' number of
46 * memory entries in the /memory node. This function may be called
47 * any time after initial_boot_param is set.
48 */
49void __init of_fdt_limit_memory(int limit)
50{
51 int memory;
52 int len;
53 const void *val;
54 int cell_size = sizeof(uint32_t)*(dt_root_addr_cells + dt_root_size_cells);
55
56 memory = fdt_path_offset(initial_boot_params, "/memory");
57 if (memory > 0) {
58 val = fdt_getprop(initial_boot_params, memory, "reg", &len);
59 if (len > limit*cell_size) {
60 len = limit*cell_size;
61 pr_debug("Limiting number of entries to %d\n", limit);
62 fdt_setprop(initial_boot_params, memory, "reg", val,
63 len);
64 }
65 }
66}
67
68bool of_fdt_device_is_available(const void *blob, unsigned long node)
69{
70 const char *status = fdt_getprop(blob, node, "status", NULL);
71
72 if (!status)
73 return true;
74
75 if (!strcmp(status, "ok") || !strcmp(status, "okay"))
76 return true;
77
78 return false;
79}
80
81static void *unflatten_dt_alloc(void **mem, unsigned long size,
82 unsigned long align)
83{
84 void *res;
85
86 *mem = PTR_ALIGN(*mem, align);
87 res = *mem;
88 *mem += size;
89
90 return res;
91}
92
93static void populate_properties(const void *blob,
94 int offset,
95 void **mem,
96 struct device_node *np,
97 const char *nodename,
98 bool dryrun)
99{
100 struct property *pp, **pprev = NULL;
101 int cur;
102 bool has_name = false;
103
104 pprev = &np->properties;
105 for (cur = fdt_first_property_offset(blob, offset);
106 cur >= 0;
107 cur = fdt_next_property_offset(blob, cur)) {
108 const __be32 *val;
109 const char *pname;
110 u32 sz;
111
112 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
113 if (!val) {
114 pr_warn("Cannot locate property at 0x%x\n", cur);
115 continue;
116 }
117
118 if (!pname) {
119 pr_warn("Cannot find property name at 0x%x\n", cur);
120 continue;
121 }
122
123 if (!strcmp(pname, "name"))
124 has_name = true;
125
126 pp = unflatten_dt_alloc(mem, sizeof(struct property),
127 __alignof__(struct property));
128 if (dryrun)
129 continue;
130
131 /* We accept flattened tree phandles either in
132 * ePAPR-style "phandle" properties, or the
133 * legacy "linux,phandle" properties. If both
134 * appear and have different values, things
135 * will get weird. Don't do that.
136 */
137 if (!strcmp(pname, "phandle") ||
138 !strcmp(pname, "linux,phandle")) {
139 if (!np->phandle)
140 np->phandle = be32_to_cpup(val);
141 }
142
143 /* And we process the "ibm,phandle" property
144 * used in pSeries dynamic device tree
145 * stuff
146 */
147 if (!strcmp(pname, "ibm,phandle"))
148 np->phandle = be32_to_cpup(val);
149
150 pp->name = (char *)pname;
151 pp->length = sz;
152 pp->value = (__be32 *)val;
153 *pprev = pp;
154 pprev = &pp->next;
155 }
156
157 /* With version 0x10 we may not have the name property,
158 * recreate it here from the unit name if absent
159 */
160 if (!has_name) {
161 const char *p = nodename, *ps = p, *pa = NULL;
162 int len;
163
164 while (*p) {
165 if ((*p) == '@')
166 pa = p;
167 else if ((*p) == '/')
168 ps = p + 1;
169 p++;
170 }
171
172 if (pa < ps)
173 pa = p;
174 len = (pa - ps) + 1;
175 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
176 __alignof__(struct property));
177 if (!dryrun) {
178 pp->name = "name";
179 pp->length = len;
180 pp->value = pp + 1;
181 *pprev = pp;
182 memcpy(pp->value, ps, len - 1);
183 ((char *)pp->value)[len - 1] = 0;
184 pr_debug("fixed up name for %s -> %s\n",
185 nodename, (char *)pp->value);
186 }
187 }
188}
189
190static int populate_node(const void *blob,
191 int offset,
192 void **mem,
193 struct device_node *dad,
194 struct device_node **pnp,
195 bool dryrun)
196{
197 struct device_node *np;
198 const char *pathp;
199 int len;
200
201 pathp = fdt_get_name(blob, offset, &len);
202 if (!pathp) {
203 *pnp = NULL;
204 return len;
205 }
206
207 len++;
208
209 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + len,
210 __alignof__(struct device_node));
211 if (!dryrun) {
212 char *fn;
213 of_node_init(np);
214 np->full_name = fn = ((char *)np) + sizeof(*np);
215
216 memcpy(fn, pathp, len);
217
218 if (dad != NULL) {
219 np->parent = dad;
220 np->sibling = dad->child;
221 dad->child = np;
222 }
223 }
224
225 populate_properties(blob, offset, mem, np, pathp, dryrun);
226 if (!dryrun) {
227 np->name = of_get_property(np, "name", NULL);
228 if (!np->name)
229 np->name = "<NULL>";
230 }
231
232 *pnp = np;
233 return 0;
234}
235
236static void reverse_nodes(struct device_node *parent)
237{
238 struct device_node *child, *next;
239
240 /* In-depth first */
241 child = parent->child;
242 while (child) {
243 reverse_nodes(child);
244
245 child = child->sibling;
246 }
247
248 /* Reverse the nodes in the child list */
249 child = parent->child;
250 parent->child = NULL;
251 while (child) {
252 next = child->sibling;
253
254 child->sibling = parent->child;
255 parent->child = child;
256 child = next;
257 }
258}
259
260/**
261 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
262 * @blob: The parent device tree blob
263 * @mem: Memory chunk to use for allocating device nodes and properties
264 * @dad: Parent struct device_node
265 * @nodepp: The device_node tree created by the call
266 *
267 * Return: The size of unflattened device tree or error code
268 */
269static int unflatten_dt_nodes(const void *blob,
270 void *mem,
271 struct device_node *dad,
272 struct device_node **nodepp)
273{
274 struct device_node *root;
275 int offset = 0, depth = 0, initial_depth = 0;
276#define FDT_MAX_DEPTH 64
277 struct device_node *nps[FDT_MAX_DEPTH];
278 void *base = mem;
279 bool dryrun = !base;
280 int ret;
281
282 if (nodepp)
283 *nodepp = NULL;
284
285 /*
286 * We're unflattening device sub-tree if @dad is valid. There are
287 * possibly multiple nodes in the first level of depth. We need
288 * set @depth to 1 to make fdt_next_node() happy as it bails
289 * immediately when negative @depth is found. Otherwise, the device
290 * nodes except the first one won't be unflattened successfully.
291 */
292 if (dad)
293 depth = initial_depth = 1;
294
295 root = dad;
296 nps[depth] = dad;
297
298 for (offset = 0;
299 offset >= 0 && depth >= initial_depth;
300 offset = fdt_next_node(blob, offset, &depth)) {
301 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH - 1))
302 continue;
303
304 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
305 !of_fdt_device_is_available(blob, offset))
306 continue;
307
308 ret = populate_node(blob, offset, &mem, nps[depth],
309 &nps[depth+1], dryrun);
310 if (ret < 0)
311 return ret;
312
313 if (!dryrun && nodepp && !*nodepp)
314 *nodepp = nps[depth+1];
315 if (!dryrun && !root)
316 root = nps[depth+1];
317 }
318
319 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
320 pr_err("Error %d processing FDT\n", offset);
321 return -EINVAL;
322 }
323
324 /*
325 * Reverse the child list. Some drivers assumes node order matches .dts
326 * node order
327 */
328 if (!dryrun)
329 reverse_nodes(root);
330
331 return mem - base;
332}
333
334/**
335 * __unflatten_device_tree - create tree of device_nodes from flat blob
336 * @blob: The blob to expand
337 * @dad: Parent device node
338 * @mynodes: The device_node tree created by the call
339 * @dt_alloc: An allocator that provides a virtual address to memory
340 * for the resulting tree
341 * @detached: if true set OF_DETACHED on @mynodes
342 *
343 * unflattens a device-tree, creating the tree of struct device_node. It also
344 * fills the "name" and "type" pointers of the nodes so the normal device-tree
345 * walking functions can be used.
346 *
347 * Return: NULL on failure or the memory chunk containing the unflattened
348 * device tree on success.
349 */
350void *__unflatten_device_tree(const void *blob,
351 struct device_node *dad,
352 struct device_node **mynodes,
353 void *(*dt_alloc)(u64 size, u64 align),
354 bool detached)
355{
356 int size;
357 void *mem;
358 int ret;
359
360 if (mynodes)
361 *mynodes = NULL;
362
363 pr_debug(" -> unflatten_device_tree()\n");
364
365 if (!blob) {
366 pr_debug("No device tree pointer\n");
367 return NULL;
368 }
369
370 pr_debug("Unflattening device tree:\n");
371 pr_debug("magic: %08x\n", fdt_magic(blob));
372 pr_debug("size: %08x\n", fdt_totalsize(blob));
373 pr_debug("version: %08x\n", fdt_version(blob));
374
375 if (fdt_check_header(blob)) {
376 pr_err("Invalid device tree blob header\n");
377 return NULL;
378 }
379
380 /* First pass, scan for size */
381 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
382 if (size <= 0)
383 return NULL;
384
385 size = ALIGN(size, 4);
386 pr_debug(" size is %d, allocating...\n", size);
387
388 /* Allocate memory for the expanded device tree */
389 mem = dt_alloc(size + 4, __alignof__(struct device_node));
390 if (!mem)
391 return NULL;
392
393 memset(mem, 0, size);
394
395 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
396
397 pr_debug(" unflattening %p...\n", mem);
398
399 /* Second pass, do actual unflattening */
400 ret = unflatten_dt_nodes(blob, mem, dad, mynodes);
401
402 if (be32_to_cpup(mem + size) != 0xdeadbeef)
403 pr_warn("End of tree marker overwritten: %08x\n",
404 be32_to_cpup(mem + size));
405
406 if (ret <= 0)
407 return NULL;
408
409 if (detached && mynodes && *mynodes) {
410 of_node_set_flag(*mynodes, OF_DETACHED);
411 pr_debug("unflattened tree is detached\n");
412 }
413
414 pr_debug(" <- unflatten_device_tree()\n");
415 return mem;
416}
417
418static void *kernel_tree_alloc(u64 size, u64 align)
419{
420 return kzalloc(size, GFP_KERNEL);
421}
422
423static DEFINE_MUTEX(of_fdt_unflatten_mutex);
424
425/**
426 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
427 * @blob: Flat device tree blob
428 * @dad: Parent device node
429 * @mynodes: The device tree created by the call
430 *
431 * unflattens the device-tree passed by the firmware, creating the
432 * tree of struct device_node. It also fills the "name" and "type"
433 * pointers of the nodes so the normal device-tree walking functions
434 * can be used.
435 *
436 * Return: NULL on failure or the memory chunk containing the unflattened
437 * device tree on success.
438 */
439void *of_fdt_unflatten_tree(const unsigned long *blob,
440 struct device_node *dad,
441 struct device_node **mynodes)
442{
443 void *mem;
444
445 mutex_lock(&of_fdt_unflatten_mutex);
446 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
447 true);
448 mutex_unlock(&of_fdt_unflatten_mutex);
449
450 return mem;
451}
452EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
453
454/* Everything below here references initial_boot_params directly. */
455int __initdata dt_root_addr_cells;
456int __initdata dt_root_size_cells;
457
458void *initial_boot_params __ro_after_init;
459phys_addr_t initial_boot_params_pa __ro_after_init;
460
461#ifdef CONFIG_OF_EARLY_FLATTREE
462
463static u32 of_fdt_crc32;
464
465/*
466 * fdt_reserve_elfcorehdr() - reserves memory for elf core header
467 *
468 * This function reserves the memory occupied by an elf core header
469 * described in the device tree. This region contains all the
470 * information about primary kernel's core image and is used by a dump
471 * capture kernel to access the system memory on primary kernel.
472 */
473static void __init fdt_reserve_elfcorehdr(void)
474{
475 if (!IS_ENABLED(CONFIG_CRASH_DUMP) || !elfcorehdr_size)
476 return;
477
478 if (memblock_is_region_reserved(elfcorehdr_addr, elfcorehdr_size)) {
479 pr_warn("elfcorehdr is overlapped\n");
480 return;
481 }
482
483 memblock_reserve(elfcorehdr_addr, elfcorehdr_size);
484
485 pr_info("Reserving %llu KiB of memory at 0x%llx for elfcorehdr\n",
486 elfcorehdr_size >> 10, elfcorehdr_addr);
487}
488
489/**
490 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
491 *
492 * This function grabs memory from early allocator for device exclusive use
493 * defined in device tree structures. It should be called by arch specific code
494 * once the early allocator (i.e. memblock) has been fully activated.
495 */
496void __init early_init_fdt_scan_reserved_mem(void)
497{
498 int n;
499 u64 base, size;
500
501 if (!initial_boot_params)
502 return;
503
504 fdt_scan_reserved_mem();
505 fdt_reserve_elfcorehdr();
506
507 /* Process header /memreserve/ fields */
508 for (n = 0; ; n++) {
509 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
510 if (!size)
511 break;
512 memblock_reserve(base, size);
513 }
514}
515
516/**
517 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
518 */
519void __init early_init_fdt_reserve_self(void)
520{
521 if (!initial_boot_params)
522 return;
523
524 /* Reserve the dtb region */
525 memblock_reserve(__pa(initial_boot_params),
526 fdt_totalsize(initial_boot_params));
527}
528
529/**
530 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
531 * @it: callback function
532 * @data: context data pointer
533 *
534 * This function is used to scan the flattened device-tree, it is
535 * used to extract the memory information at boot before we can
536 * unflatten the tree
537 */
538int __init of_scan_flat_dt(int (*it)(unsigned long node,
539 const char *uname, int depth,
540 void *data),
541 void *data)
542{
543 const void *blob = initial_boot_params;
544 const char *pathp;
545 int offset, rc = 0, depth = -1;
546
547 if (!blob)
548 return 0;
549
550 for (offset = fdt_next_node(blob, -1, &depth);
551 offset >= 0 && depth >= 0 && !rc;
552 offset = fdt_next_node(blob, offset, &depth)) {
553
554 pathp = fdt_get_name(blob, offset, NULL);
555 rc = it(offset, pathp, depth, data);
556 }
557 return rc;
558}
559
560/**
561 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
562 * @parent: parent node
563 * @it: callback function
564 * @data: context data pointer
565 *
566 * This function is used to scan sub-nodes of a node.
567 */
568int __init of_scan_flat_dt_subnodes(unsigned long parent,
569 int (*it)(unsigned long node,
570 const char *uname,
571 void *data),
572 void *data)
573{
574 const void *blob = initial_boot_params;
575 int node;
576
577 fdt_for_each_subnode(node, blob, parent) {
578 const char *pathp;
579 int rc;
580
581 pathp = fdt_get_name(blob, node, NULL);
582 rc = it(node, pathp, data);
583 if (rc)
584 return rc;
585 }
586 return 0;
587}
588
589/**
590 * of_get_flat_dt_subnode_by_name - get the subnode by given name
591 *
592 * @node: the parent node
593 * @uname: the name of subnode
594 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
595 */
596
597int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
598{
599 return fdt_subnode_offset(initial_boot_params, node, uname);
600}
601
602/*
603 * of_get_flat_dt_root - find the root node in the flat blob
604 */
605unsigned long __init of_get_flat_dt_root(void)
606{
607 return 0;
608}
609
610/*
611 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
612 *
613 * This function can be used within scan_flattened_dt callback to get
614 * access to properties
615 */
616const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
617 int *size)
618{
619 return fdt_getprop(initial_boot_params, node, name, size);
620}
621
622/**
623 * of_fdt_is_compatible - Return true if given node from the given blob has
624 * compat in its compatible list
625 * @blob: A device tree blob
626 * @node: node to test
627 * @compat: compatible string to compare with compatible list.
628 *
629 * Return: a non-zero value on match with smaller values returned for more
630 * specific compatible values.
631 */
632static int of_fdt_is_compatible(const void *blob,
633 unsigned long node, const char *compat)
634{
635 const char *cp;
636 int cplen;
637 unsigned long l, score = 0;
638
639 cp = fdt_getprop(blob, node, "compatible", &cplen);
640 if (cp == NULL)
641 return 0;
642 while (cplen > 0) {
643 score++;
644 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
645 return score;
646 l = strlen(cp) + 1;
647 cp += l;
648 cplen -= l;
649 }
650
651 return 0;
652}
653
654/**
655 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
656 * @node: node to test
657 * @compat: compatible string to compare with compatible list.
658 */
659int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
660{
661 return of_fdt_is_compatible(initial_boot_params, node, compat);
662}
663
664/*
665 * of_flat_dt_match - Return true if node matches a list of compatible values
666 */
667static int __init of_flat_dt_match(unsigned long node, const char *const *compat)
668{
669 unsigned int tmp, score = 0;
670
671 if (!compat)
672 return 0;
673
674 while (*compat) {
675 tmp = of_fdt_is_compatible(initial_boot_params, node, *compat);
676 if (tmp && (score == 0 || (tmp < score)))
677 score = tmp;
678 compat++;
679 }
680
681 return score;
682}
683
684/*
685 * of_get_flat_dt_phandle - Given a node in the flat blob, return the phandle
686 */
687uint32_t __init of_get_flat_dt_phandle(unsigned long node)
688{
689 return fdt_get_phandle(initial_boot_params, node);
690}
691
692const char * __init of_flat_dt_get_machine_name(void)
693{
694 const char *name;
695 unsigned long dt_root = of_get_flat_dt_root();
696
697 name = of_get_flat_dt_prop(dt_root, "model", NULL);
698 if (!name)
699 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
700 return name;
701}
702
703/**
704 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
705 *
706 * @default_match: A machine specific ptr to return in case of no match.
707 * @get_next_compat: callback function to return next compatible match table.
708 *
709 * Iterate through machine match tables to find the best match for the machine
710 * compatible string in the FDT.
711 */
712const void * __init of_flat_dt_match_machine(const void *default_match,
713 const void * (*get_next_compat)(const char * const**))
714{
715 const void *data = NULL;
716 const void *best_data = default_match;
717 const char *const *compat;
718 unsigned long dt_root;
719 unsigned int best_score = ~1, score = 0;
720
721 dt_root = of_get_flat_dt_root();
722 while ((data = get_next_compat(&compat))) {
723 score = of_flat_dt_match(dt_root, compat);
724 if (score > 0 && score < best_score) {
725 best_data = data;
726 best_score = score;
727 }
728 }
729 if (!best_data) {
730 const char *prop;
731 int size;
732
733 pr_err("\n unrecognized device tree list:\n[ ");
734
735 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
736 if (prop) {
737 while (size > 0) {
738 printk("'%s' ", prop);
739 size -= strlen(prop) + 1;
740 prop += strlen(prop) + 1;
741 }
742 }
743 printk("]\n\n");
744 return NULL;
745 }
746
747 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
748
749 return best_data;
750}
751
752static void __early_init_dt_declare_initrd(unsigned long start,
753 unsigned long end)
754{
755 /*
756 * __va() is not yet available this early on some platforms. In that
757 * case, the platform uses phys_initrd_start/phys_initrd_size instead
758 * and does the VA conversion itself.
759 */
760 if (!IS_ENABLED(CONFIG_ARM64) &&
761 !(IS_ENABLED(CONFIG_RISCV) && IS_ENABLED(CONFIG_64BIT))) {
762 initrd_start = (unsigned long)__va(start);
763 initrd_end = (unsigned long)__va(end);
764 initrd_below_start_ok = 1;
765 }
766}
767
768/**
769 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
770 * @node: reference to node containing initrd location ('chosen')
771 */
772static void __init early_init_dt_check_for_initrd(unsigned long node)
773{
774 u64 start, end;
775 int len;
776 const __be32 *prop;
777
778 if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD))
779 return;
780
781 pr_debug("Looking for initrd properties... ");
782
783 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
784 if (!prop)
785 return;
786 start = of_read_number(prop, len/4);
787
788 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
789 if (!prop)
790 return;
791 end = of_read_number(prop, len/4);
792 if (start > end)
793 return;
794
795 __early_init_dt_declare_initrd(start, end);
796 phys_initrd_start = start;
797 phys_initrd_size = end - start;
798
799 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", start, end);
800}
801
802/**
803 * early_init_dt_check_for_elfcorehdr - Decode elfcorehdr location from flat
804 * tree
805 * @node: reference to node containing elfcorehdr location ('chosen')
806 */
807static void __init early_init_dt_check_for_elfcorehdr(unsigned long node)
808{
809 const __be32 *prop;
810 int len;
811
812 if (!IS_ENABLED(CONFIG_CRASH_DUMP))
813 return;
814
815 pr_debug("Looking for elfcorehdr property... ");
816
817 prop = of_get_flat_dt_prop(node, "linux,elfcorehdr", &len);
818 if (!prop || (len < (dt_root_addr_cells + dt_root_size_cells)))
819 return;
820
821 elfcorehdr_addr = dt_mem_next_cell(dt_root_addr_cells, &prop);
822 elfcorehdr_size = dt_mem_next_cell(dt_root_size_cells, &prop);
823
824 pr_debug("elfcorehdr_start=0x%llx elfcorehdr_size=0x%llx\n",
825 elfcorehdr_addr, elfcorehdr_size);
826}
827
828static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
829
830/*
831 * The main usage of linux,usable-memory-range is for crash dump kernel.
832 * Originally, the number of usable-memory regions is one. Now there may
833 * be two regions, low region and high region.
834 * To make compatibility with existing user-space and older kdump, the low
835 * region is always the last range of linux,usable-memory-range if exist.
836 */
837#define MAX_USABLE_RANGES 2
838
839/**
840 * early_init_dt_check_for_usable_mem_range - Decode usable memory range
841 * location from flat tree
842 */
843void __init early_init_dt_check_for_usable_mem_range(void)
844{
845 struct memblock_region rgn[MAX_USABLE_RANGES] = {0};
846 const __be32 *prop, *endp;
847 int len, i;
848 unsigned long node = chosen_node_offset;
849
850 if ((long)node < 0)
851 return;
852
853 pr_debug("Looking for usable-memory-range property... ");
854
855 prop = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len);
856 if (!prop || (len % (dt_root_addr_cells + dt_root_size_cells)))
857 return;
858
859 endp = prop + (len / sizeof(__be32));
860 for (i = 0; i < MAX_USABLE_RANGES && prop < endp; i++) {
861 rgn[i].base = dt_mem_next_cell(dt_root_addr_cells, &prop);
862 rgn[i].size = dt_mem_next_cell(dt_root_size_cells, &prop);
863
864 pr_debug("cap_mem_regions[%d]: base=%pa, size=%pa\n",
865 i, &rgn[i].base, &rgn[i].size);
866 }
867
868 memblock_cap_memory_range(rgn[0].base, rgn[0].size);
869 for (i = 1; i < MAX_USABLE_RANGES && rgn[i].size; i++)
870 memblock_add(rgn[i].base, rgn[i].size);
871}
872
873#ifdef CONFIG_SERIAL_EARLYCON
874
875int __init early_init_dt_scan_chosen_stdout(void)
876{
877 int offset;
878 const char *p, *q, *options = NULL;
879 int l;
880 const struct earlycon_id *match;
881 const void *fdt = initial_boot_params;
882 int ret;
883
884 offset = fdt_path_offset(fdt, "/chosen");
885 if (offset < 0)
886 offset = fdt_path_offset(fdt, "/chosen@0");
887 if (offset < 0)
888 return -ENOENT;
889
890 p = fdt_getprop(fdt, offset, "stdout-path", &l);
891 if (!p)
892 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
893 if (!p || !l)
894 return -ENOENT;
895
896 q = strchrnul(p, ':');
897 if (*q != '\0')
898 options = q + 1;
899 l = q - p;
900
901 /* Get the node specified by stdout-path */
902 offset = fdt_path_offset_namelen(fdt, p, l);
903 if (offset < 0) {
904 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
905 return 0;
906 }
907
908 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
909 if (!match->compatible[0])
910 continue;
911
912 if (fdt_node_check_compatible(fdt, offset, match->compatible))
913 continue;
914
915 ret = of_setup_earlycon(match, offset, options);
916 if (!ret || ret == -EALREADY)
917 return 0;
918 }
919 return -ENODEV;
920}
921#endif
922
923/*
924 * early_init_dt_scan_root - fetch the top level address and size cells
925 */
926int __init early_init_dt_scan_root(void)
927{
928 const __be32 *prop;
929 const void *fdt = initial_boot_params;
930 int node = fdt_path_offset(fdt, "/");
931
932 if (node < 0)
933 return -ENODEV;
934
935 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
936 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
937
938 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
939 if (!WARN(!prop, "No '#size-cells' in root node\n"))
940 dt_root_size_cells = be32_to_cpup(prop);
941 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
942
943 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
944 if (!WARN(!prop, "No '#address-cells' in root node\n"))
945 dt_root_addr_cells = be32_to_cpup(prop);
946 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
947
948 return 0;
949}
950
951u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
952{
953 const __be32 *p = *cellp;
954
955 *cellp = p + s;
956 return of_read_number(p, s);
957}
958
959/*
960 * early_init_dt_scan_memory - Look for and parse memory nodes
961 */
962int __init early_init_dt_scan_memory(void)
963{
964 int node, found_memory = 0;
965 const void *fdt = initial_boot_params;
966
967 fdt_for_each_subnode(node, fdt, 0) {
968 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
969 const __be32 *reg, *endp;
970 int l;
971 bool hotpluggable;
972
973 /* We are scanning "memory" nodes only */
974 if (type == NULL || strcmp(type, "memory") != 0)
975 continue;
976
977 if (!of_fdt_device_is_available(fdt, node))
978 continue;
979
980 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
981 if (reg == NULL)
982 reg = of_get_flat_dt_prop(node, "reg", &l);
983 if (reg == NULL)
984 continue;
985
986 endp = reg + (l / sizeof(__be32));
987 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
988
989 pr_debug("memory scan node %s, reg size %d,\n",
990 fdt_get_name(fdt, node, NULL), l);
991
992 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
993 u64 base, size;
994
995 base = dt_mem_next_cell(dt_root_addr_cells, ®);
996 size = dt_mem_next_cell(dt_root_size_cells, ®);
997
998 if (size == 0)
999 continue;
1000 pr_debug(" - %llx, %llx\n", base, size);
1001
1002 early_init_dt_add_memory_arch(base, size);
1003
1004 found_memory = 1;
1005
1006 if (!hotpluggable)
1007 continue;
1008
1009 if (memblock_mark_hotplug(base, size))
1010 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1011 base, base + size);
1012 }
1013 }
1014 return found_memory;
1015}
1016
1017int __init early_init_dt_scan_chosen(char *cmdline)
1018{
1019 int l, node;
1020 const char *p;
1021 const void *rng_seed;
1022 const void *fdt = initial_boot_params;
1023
1024 node = fdt_path_offset(fdt, "/chosen");
1025 if (node < 0)
1026 node = fdt_path_offset(fdt, "/chosen@0");
1027 if (node < 0)
1028 /* Handle the cmdline config options even if no /chosen node */
1029 goto handle_cmdline;
1030
1031 chosen_node_offset = node;
1032
1033 early_init_dt_check_for_initrd(node);
1034 early_init_dt_check_for_elfcorehdr(node);
1035
1036 rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
1037 if (rng_seed && l > 0) {
1038 add_bootloader_randomness(rng_seed, l);
1039
1040 /* try to clear seed so it won't be found. */
1041 fdt_nop_property(initial_boot_params, node, "rng-seed");
1042
1043 /* update CRC check value */
1044 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1045 fdt_totalsize(initial_boot_params));
1046 }
1047
1048 /* Retrieve command line */
1049 p = of_get_flat_dt_prop(node, "bootargs", &l);
1050 if (p != NULL && l > 0)
1051 strscpy(cmdline, p, min(l, COMMAND_LINE_SIZE));
1052
1053handle_cmdline:
1054 /*
1055 * CONFIG_CMDLINE is meant to be a default in case nothing else
1056 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1057 * is set in which case we override whatever was found earlier.
1058 */
1059#ifdef CONFIG_CMDLINE
1060#if defined(CONFIG_CMDLINE_EXTEND)
1061 strlcat(cmdline, " ", COMMAND_LINE_SIZE);
1062 strlcat(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1063#elif defined(CONFIG_CMDLINE_FORCE)
1064 strscpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1065#else
1066 /* No arguments from boot loader, use kernel's cmdl*/
1067 if (!((char *)cmdline)[0])
1068 strscpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1069#endif
1070#endif /* CONFIG_CMDLINE */
1071
1072 pr_debug("Command line is: %s\n", (char *)cmdline);
1073
1074 return 0;
1075}
1076
1077#ifndef MIN_MEMBLOCK_ADDR
1078#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1079#endif
1080#ifndef MAX_MEMBLOCK_ADDR
1081#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1082#endif
1083
1084void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1085{
1086 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1087
1088 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1089 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1090 base, base + size);
1091 return;
1092 }
1093
1094 if (!PAGE_ALIGNED(base)) {
1095 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1096 base = PAGE_ALIGN(base);
1097 }
1098 size &= PAGE_MASK;
1099
1100 if (base > MAX_MEMBLOCK_ADDR) {
1101 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1102 base, base + size);
1103 return;
1104 }
1105
1106 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1107 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1108 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1109 size = MAX_MEMBLOCK_ADDR - base + 1;
1110 }
1111
1112 if (base + size < phys_offset) {
1113 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1114 base, base + size);
1115 return;
1116 }
1117 if (base < phys_offset) {
1118 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1119 base, phys_offset);
1120 size -= phys_offset - base;
1121 base = phys_offset;
1122 }
1123 memblock_add(base, size);
1124}
1125
1126static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1127{
1128 void *ptr = memblock_alloc(size, align);
1129
1130 if (!ptr)
1131 panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
1132 __func__, size, align);
1133
1134 return ptr;
1135}
1136
1137bool __init early_init_dt_verify(void *dt_virt, phys_addr_t dt_phys)
1138{
1139 if (!dt_virt)
1140 return false;
1141
1142 /* check device tree validity */
1143 if (fdt_check_header(dt_virt))
1144 return false;
1145
1146 /* Setup flat device-tree pointer */
1147 initial_boot_params = dt_virt;
1148 initial_boot_params_pa = dt_phys;
1149 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1150 fdt_totalsize(initial_boot_params));
1151
1152 /* Initialize {size,address}-cells info */
1153 early_init_dt_scan_root();
1154
1155 return true;
1156}
1157
1158
1159void __init early_init_dt_scan_nodes(void)
1160{
1161 int rc;
1162
1163 /* Retrieve various information from the /chosen node */
1164 rc = early_init_dt_scan_chosen(boot_command_line);
1165 if (rc)
1166 pr_warn("No chosen node found, continuing without\n");
1167
1168 /* Setup memory, calling early_init_dt_add_memory_arch */
1169 early_init_dt_scan_memory();
1170
1171 /* Handle linux,usable-memory-range property */
1172 early_init_dt_check_for_usable_mem_range();
1173}
1174
1175bool __init early_init_dt_scan(void *dt_virt, phys_addr_t dt_phys)
1176{
1177 bool status;
1178
1179 status = early_init_dt_verify(dt_virt, dt_phys);
1180 if (!status)
1181 return false;
1182
1183 early_init_dt_scan_nodes();
1184 return true;
1185}
1186
1187static void *__init copy_device_tree(void *fdt)
1188{
1189 int size;
1190 void *dt;
1191
1192 size = fdt_totalsize(fdt);
1193 dt = early_init_dt_alloc_memory_arch(size,
1194 roundup_pow_of_two(FDT_V17_SIZE));
1195
1196 if (dt)
1197 memcpy(dt, fdt, size);
1198
1199 return dt;
1200}
1201
1202/**
1203 * unflatten_device_tree - create tree of device_nodes from flat blob
1204 *
1205 * unflattens the device-tree passed by the firmware, creating the
1206 * tree of struct device_node. It also fills the "name" and "type"
1207 * pointers of the nodes so the normal device-tree walking functions
1208 * can be used.
1209 */
1210void __init unflatten_device_tree(void)
1211{
1212 void *fdt = initial_boot_params;
1213
1214 /* Save the statically-placed regions in the reserved_mem array */
1215 fdt_scan_reserved_mem_reg_nodes();
1216
1217 /* Populate an empty root node when bootloader doesn't provide one */
1218 if (!fdt) {
1219 fdt = (void *) __dtb_empty_root_begin;
1220 /* fdt_totalsize() will be used for copy size */
1221 if (fdt_totalsize(fdt) >
1222 __dtb_empty_root_end - __dtb_empty_root_begin) {
1223 pr_err("invalid size in dtb_empty_root\n");
1224 return;
1225 }
1226 of_fdt_crc32 = crc32_be(~0, fdt, fdt_totalsize(fdt));
1227 fdt = copy_device_tree(fdt);
1228 }
1229
1230 __unflatten_device_tree(fdt, NULL, &of_root,
1231 early_init_dt_alloc_memory_arch, false);
1232
1233 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1234 of_alias_scan(early_init_dt_alloc_memory_arch);
1235
1236 unittest_unflatten_overlay_base();
1237}
1238
1239/**
1240 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1241 *
1242 * Copies and unflattens the device-tree passed by the firmware, creating the
1243 * tree of struct device_node. It also fills the "name" and "type"
1244 * pointers of the nodes so the normal device-tree walking functions
1245 * can be used. This should only be used when the FDT memory has not been
1246 * reserved such is the case when the FDT is built-in to the kernel init
1247 * section. If the FDT memory is reserved already then unflatten_device_tree
1248 * should be used instead.
1249 */
1250void __init unflatten_and_copy_device_tree(void)
1251{
1252 if (initial_boot_params)
1253 initial_boot_params = copy_device_tree(initial_boot_params);
1254
1255 unflatten_device_tree();
1256}
1257
1258#ifdef CONFIG_SYSFS
1259static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1260 struct bin_attribute *bin_attr,
1261 char *buf, loff_t off, size_t count)
1262{
1263 memcpy(buf, initial_boot_params + off, count);
1264 return count;
1265}
1266
1267static int __init of_fdt_raw_init(void)
1268{
1269 static struct bin_attribute of_fdt_raw_attr =
1270 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1271
1272 if (!initial_boot_params)
1273 return 0;
1274
1275 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1276 fdt_totalsize(initial_boot_params))) {
1277 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1278 return 0;
1279 }
1280 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1281 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1282}
1283late_initcall(of_fdt_raw_init);
1284#endif
1285
1286#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/memblock.h>
15#include <linux/mutex.h>
16#include <linux/of.h>
17#include <linux/of_fdt.h>
18#include <linux/of_reserved_mem.h>
19#include <linux/sizes.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/slab.h>
23#include <linux/libfdt.h>
24#include <linux/debugfs.h>
25#include <linux/serial_core.h>
26#include <linux/sysfs.h>
27#include <linux/random.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 __init 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
82static bool of_fdt_device_is_available(const void *blob, unsigned long node)
83{
84 const char *status = fdt_getprop(blob, node, "status", NULL);
85
86 if (!status)
87 return true;
88
89 if (!strcmp(status, "ok") || !strcmp(status, "okay"))
90 return true;
91
92 return false;
93}
94
95static void *unflatten_dt_alloc(void **mem, unsigned long size,
96 unsigned long align)
97{
98 void *res;
99
100 *mem = PTR_ALIGN(*mem, align);
101 res = *mem;
102 *mem += size;
103
104 return res;
105}
106
107static void populate_properties(const void *blob,
108 int offset,
109 void **mem,
110 struct device_node *np,
111 const char *nodename,
112 bool dryrun)
113{
114 struct property *pp, **pprev = NULL;
115 int cur;
116 bool has_name = false;
117
118 pprev = &np->properties;
119 for (cur = fdt_first_property_offset(blob, offset);
120 cur >= 0;
121 cur = fdt_next_property_offset(blob, cur)) {
122 const __be32 *val;
123 const char *pname;
124 u32 sz;
125
126 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
127 if (!val) {
128 pr_warn("Cannot locate property at 0x%x\n", cur);
129 continue;
130 }
131
132 if (!pname) {
133 pr_warn("Cannot find property name at 0x%x\n", cur);
134 continue;
135 }
136
137 if (!strcmp(pname, "name"))
138 has_name = true;
139
140 pp = unflatten_dt_alloc(mem, sizeof(struct property),
141 __alignof__(struct property));
142 if (dryrun)
143 continue;
144
145 /* We accept flattened tree phandles either in
146 * ePAPR-style "phandle" properties, or the
147 * legacy "linux,phandle" properties. If both
148 * appear and have different values, things
149 * will get weird. Don't do that.
150 */
151 if (!strcmp(pname, "phandle") ||
152 !strcmp(pname, "linux,phandle")) {
153 if (!np->phandle)
154 np->phandle = be32_to_cpup(val);
155 }
156
157 /* And we process the "ibm,phandle" property
158 * used in pSeries dynamic device tree
159 * stuff
160 */
161 if (!strcmp(pname, "ibm,phandle"))
162 np->phandle = be32_to_cpup(val);
163
164 pp->name = (char *)pname;
165 pp->length = sz;
166 pp->value = (__be32 *)val;
167 *pprev = pp;
168 pprev = &pp->next;
169 }
170
171 /* With version 0x10 we may not have the name property,
172 * recreate it here from the unit name if absent
173 */
174 if (!has_name) {
175 const char *p = nodename, *ps = p, *pa = NULL;
176 int len;
177
178 while (*p) {
179 if ((*p) == '@')
180 pa = p;
181 else if ((*p) == '/')
182 ps = p + 1;
183 p++;
184 }
185
186 if (pa < ps)
187 pa = p;
188 len = (pa - ps) + 1;
189 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
190 __alignof__(struct property));
191 if (!dryrun) {
192 pp->name = "name";
193 pp->length = len;
194 pp->value = pp + 1;
195 *pprev = pp;
196 pprev = &pp->next;
197 memcpy(pp->value, ps, len - 1);
198 ((char *)pp->value)[len - 1] = 0;
199 pr_debug("fixed up name for %s -> %s\n",
200 nodename, (char *)pp->value);
201 }
202 }
203
204 if (!dryrun)
205 *pprev = NULL;
206}
207
208static bool populate_node(const void *blob,
209 int offset,
210 void **mem,
211 struct device_node *dad,
212 struct device_node **pnp,
213 bool dryrun)
214{
215 struct device_node *np;
216 const char *pathp;
217 unsigned int l, allocl;
218
219 pathp = fdt_get_name(blob, offset, &l);
220 if (!pathp) {
221 *pnp = NULL;
222 return false;
223 }
224
225 allocl = ++l;
226
227 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + allocl,
228 __alignof__(struct device_node));
229 if (!dryrun) {
230 char *fn;
231 of_node_init(np);
232 np->full_name = fn = ((char *)np) + sizeof(*np);
233
234 memcpy(fn, pathp, l);
235
236 if (dad != NULL) {
237 np->parent = dad;
238 np->sibling = dad->child;
239 dad->child = np;
240 }
241 }
242
243 populate_properties(blob, offset, mem, np, pathp, dryrun);
244 if (!dryrun) {
245 np->name = of_get_property(np, "name", NULL);
246 if (!np->name)
247 np->name = "<NULL>";
248 }
249
250 *pnp = np;
251 return true;
252}
253
254static void reverse_nodes(struct device_node *parent)
255{
256 struct device_node *child, *next;
257
258 /* In-depth first */
259 child = parent->child;
260 while (child) {
261 reverse_nodes(child);
262
263 child = child->sibling;
264 }
265
266 /* Reverse the nodes in the child list */
267 child = parent->child;
268 parent->child = NULL;
269 while (child) {
270 next = child->sibling;
271
272 child->sibling = parent->child;
273 parent->child = child;
274 child = next;
275 }
276}
277
278/**
279 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
280 * @blob: The parent device tree blob
281 * @mem: Memory chunk to use for allocating device nodes and properties
282 * @dad: Parent struct device_node
283 * @nodepp: The device_node tree created by the call
284 *
285 * It returns the size of unflattened device tree or error code
286 */
287static int unflatten_dt_nodes(const void *blob,
288 void *mem,
289 struct device_node *dad,
290 struct device_node **nodepp)
291{
292 struct device_node *root;
293 int offset = 0, depth = 0, initial_depth = 0;
294#define FDT_MAX_DEPTH 64
295 struct device_node *nps[FDT_MAX_DEPTH];
296 void *base = mem;
297 bool dryrun = !base;
298
299 if (nodepp)
300 *nodepp = NULL;
301
302 /*
303 * We're unflattening device sub-tree if @dad is valid. There are
304 * possibly multiple nodes in the first level of depth. We need
305 * set @depth to 1 to make fdt_next_node() happy as it bails
306 * immediately when negative @depth is found. Otherwise, the device
307 * nodes except the first one won't be unflattened successfully.
308 */
309 if (dad)
310 depth = initial_depth = 1;
311
312 root = dad;
313 nps[depth] = dad;
314
315 for (offset = 0;
316 offset >= 0 && depth >= initial_depth;
317 offset = fdt_next_node(blob, offset, &depth)) {
318 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
319 continue;
320
321 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
322 !of_fdt_device_is_available(blob, offset))
323 continue;
324
325 if (!populate_node(blob, offset, &mem, nps[depth],
326 &nps[depth+1], dryrun))
327 return mem - base;
328
329 if (!dryrun && nodepp && !*nodepp)
330 *nodepp = nps[depth+1];
331 if (!dryrun && !root)
332 root = nps[depth+1];
333 }
334
335 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
336 pr_err("Error %d processing FDT\n", offset);
337 return -EINVAL;
338 }
339
340 /*
341 * Reverse the child list. Some drivers assumes node order matches .dts
342 * node order
343 */
344 if (!dryrun)
345 reverse_nodes(root);
346
347 return mem - base;
348}
349
350/**
351 * __unflatten_device_tree - create tree of device_nodes from flat blob
352 *
353 * unflattens a device-tree, creating the
354 * tree of struct device_node. It also fills the "name" and "type"
355 * pointers of the nodes so the normal device-tree walking functions
356 * can be used.
357 * @blob: The blob to expand
358 * @dad: Parent device node
359 * @mynodes: The device_node tree created by the call
360 * @dt_alloc: An allocator that provides a virtual address to memory
361 * for the resulting tree
362 * @detached: if true set OF_DETACHED on @mynodes
363 *
364 * Returns NULL on failure or the memory chunk containing the unflattened
365 * device tree on success.
366 */
367void *__unflatten_device_tree(const void *blob,
368 struct device_node *dad,
369 struct device_node **mynodes,
370 void *(*dt_alloc)(u64 size, u64 align),
371 bool detached)
372{
373 int size;
374 void *mem;
375
376 pr_debug(" -> unflatten_device_tree()\n");
377
378 if (!blob) {
379 pr_debug("No device tree pointer\n");
380 return NULL;
381 }
382
383 pr_debug("Unflattening device tree:\n");
384 pr_debug("magic: %08x\n", fdt_magic(blob));
385 pr_debug("size: %08x\n", fdt_totalsize(blob));
386 pr_debug("version: %08x\n", fdt_version(blob));
387
388 if (fdt_check_header(blob)) {
389 pr_err("Invalid device tree blob header\n");
390 return NULL;
391 }
392
393 /* First pass, scan for size */
394 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
395 if (size < 0)
396 return NULL;
397
398 size = ALIGN(size, 4);
399 pr_debug(" size is %d, allocating...\n", size);
400
401 /* Allocate memory for the expanded device tree */
402 mem = dt_alloc(size + 4, __alignof__(struct device_node));
403 if (!mem)
404 return NULL;
405
406 memset(mem, 0, size);
407
408 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
409
410 pr_debug(" unflattening %p...\n", mem);
411
412 /* Second pass, do actual unflattening */
413 unflatten_dt_nodes(blob, mem, dad, mynodes);
414 if (be32_to_cpup(mem + size) != 0xdeadbeef)
415 pr_warn("End of tree marker overwritten: %08x\n",
416 be32_to_cpup(mem + size));
417
418 if (detached && mynodes) {
419 of_node_set_flag(*mynodes, OF_DETACHED);
420 pr_debug("unflattened tree is detached\n");
421 }
422
423 pr_debug(" <- unflatten_device_tree()\n");
424 return mem;
425}
426
427static void *kernel_tree_alloc(u64 size, u64 align)
428{
429 return kzalloc(size, GFP_KERNEL);
430}
431
432static DEFINE_MUTEX(of_fdt_unflatten_mutex);
433
434/**
435 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
436 * @blob: Flat device tree blob
437 * @dad: Parent device node
438 * @mynodes: The device tree created by the call
439 *
440 * unflattens the device-tree passed by the firmware, creating the
441 * tree of struct device_node. It also fills the "name" and "type"
442 * pointers of the nodes so the normal device-tree walking functions
443 * can be used.
444 *
445 * Returns NULL on failure or the memory chunk containing the unflattened
446 * device tree on success.
447 */
448void *of_fdt_unflatten_tree(const unsigned long *blob,
449 struct device_node *dad,
450 struct device_node **mynodes)
451{
452 void *mem;
453
454 mutex_lock(&of_fdt_unflatten_mutex);
455 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
456 true);
457 mutex_unlock(&of_fdt_unflatten_mutex);
458
459 return mem;
460}
461EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
462
463/* Everything below here references initial_boot_params directly. */
464int __initdata dt_root_addr_cells;
465int __initdata dt_root_size_cells;
466
467void *initial_boot_params __ro_after_init;
468
469#ifdef CONFIG_OF_EARLY_FLATTREE
470
471static u32 of_fdt_crc32;
472
473/**
474 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
475 */
476static int __init __reserved_mem_reserve_reg(unsigned long node,
477 const char *uname)
478{
479 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
480 phys_addr_t base, size;
481 int len;
482 const __be32 *prop;
483 int first = 1;
484 bool nomap;
485
486 prop = of_get_flat_dt_prop(node, "reg", &len);
487 if (!prop)
488 return -ENOENT;
489
490 if (len && len % t_len != 0) {
491 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
492 uname);
493 return -EINVAL;
494 }
495
496 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
497
498 while (len >= t_len) {
499 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
500 size = dt_mem_next_cell(dt_root_size_cells, &prop);
501
502 if (size &&
503 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
504 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
505 uname, &base, (unsigned long)size / SZ_1M);
506 else
507 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
508 uname, &base, (unsigned long)size / SZ_1M);
509
510 len -= t_len;
511 if (first) {
512 fdt_reserved_mem_save_node(node, uname, base, size);
513 first = 0;
514 }
515 }
516 return 0;
517}
518
519/**
520 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
521 * in /reserved-memory matches the values supported by the current implementation,
522 * also check if ranges property has been provided
523 */
524static int __init __reserved_mem_check_root(unsigned long node)
525{
526 const __be32 *prop;
527
528 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
529 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
530 return -EINVAL;
531
532 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
533 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
534 return -EINVAL;
535
536 prop = of_get_flat_dt_prop(node, "ranges", NULL);
537 if (!prop)
538 return -EINVAL;
539 return 0;
540}
541
542/**
543 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
544 */
545static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
546 int depth, void *data)
547{
548 static int found;
549 int err;
550
551 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
552 if (__reserved_mem_check_root(node) != 0) {
553 pr_err("Reserved memory: unsupported node format, ignoring\n");
554 /* break scan */
555 return 1;
556 }
557 found = 1;
558 /* scan next node */
559 return 0;
560 } else if (!found) {
561 /* scan next node */
562 return 0;
563 } else if (found && depth < 2) {
564 /* scanning of /reserved-memory has been finished */
565 return 1;
566 }
567
568 if (!of_fdt_device_is_available(initial_boot_params, node))
569 return 0;
570
571 err = __reserved_mem_reserve_reg(node, uname);
572 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
573 fdt_reserved_mem_save_node(node, uname, 0, 0);
574
575 /* scan next node */
576 return 0;
577}
578
579/**
580 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
581 *
582 * This function grabs memory from early allocator for device exclusive use
583 * defined in device tree structures. It should be called by arch specific code
584 * once the early allocator (i.e. memblock) has been fully activated.
585 */
586void __init early_init_fdt_scan_reserved_mem(void)
587{
588 int n;
589 u64 base, size;
590
591 if (!initial_boot_params)
592 return;
593
594 /* Process header /memreserve/ fields */
595 for (n = 0; ; n++) {
596 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
597 if (!size)
598 break;
599 early_init_dt_reserve_memory_arch(base, size, false);
600 }
601
602 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
603 fdt_init_reserved_mem();
604}
605
606/**
607 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
608 */
609void __init early_init_fdt_reserve_self(void)
610{
611 if (!initial_boot_params)
612 return;
613
614 /* Reserve the dtb region */
615 early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
616 fdt_totalsize(initial_boot_params),
617 false);
618}
619
620/**
621 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
622 * @it: callback function
623 * @data: context data pointer
624 *
625 * This function is used to scan the flattened device-tree, it is
626 * used to extract the memory information at boot before we can
627 * unflatten the tree
628 */
629int __init of_scan_flat_dt(int (*it)(unsigned long node,
630 const char *uname, int depth,
631 void *data),
632 void *data)
633{
634 const void *blob = initial_boot_params;
635 const char *pathp;
636 int offset, rc = 0, depth = -1;
637
638 if (!blob)
639 return 0;
640
641 for (offset = fdt_next_node(blob, -1, &depth);
642 offset >= 0 && depth >= 0 && !rc;
643 offset = fdt_next_node(blob, offset, &depth)) {
644
645 pathp = fdt_get_name(blob, offset, NULL);
646 rc = it(offset, pathp, depth, data);
647 }
648 return rc;
649}
650
651/**
652 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
653 * @it: callback function
654 * @data: context data pointer
655 *
656 * This function is used to scan sub-nodes of a node.
657 */
658int __init of_scan_flat_dt_subnodes(unsigned long parent,
659 int (*it)(unsigned long node,
660 const char *uname,
661 void *data),
662 void *data)
663{
664 const void *blob = initial_boot_params;
665 int node;
666
667 fdt_for_each_subnode(node, blob, parent) {
668 const char *pathp;
669 int rc;
670
671 pathp = fdt_get_name(blob, node, NULL);
672 rc = it(node, pathp, data);
673 if (rc)
674 return rc;
675 }
676 return 0;
677}
678
679/**
680 * of_get_flat_dt_subnode_by_name - get the subnode by given name
681 *
682 * @node: the parent node
683 * @uname: the name of subnode
684 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
685 */
686
687int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
688{
689 return fdt_subnode_offset(initial_boot_params, node, uname);
690}
691
692/**
693 * of_get_flat_dt_root - find the root node in the flat blob
694 */
695unsigned long __init of_get_flat_dt_root(void)
696{
697 return 0;
698}
699
700/**
701 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
702 *
703 * This function can be used within scan_flattened_dt callback to get
704 * access to properties
705 */
706const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
707 int *size)
708{
709 return fdt_getprop(initial_boot_params, node, name, size);
710}
711
712/**
713 * of_fdt_is_compatible - Return true if given node from the given blob has
714 * compat in its compatible list
715 * @blob: A device tree blob
716 * @node: node to test
717 * @compat: compatible string to compare with compatible list.
718 *
719 * On match, returns a non-zero value with smaller values returned for more
720 * specific compatible values.
721 */
722static int of_fdt_is_compatible(const void *blob,
723 unsigned long node, const char *compat)
724{
725 const char *cp;
726 int cplen;
727 unsigned long l, score = 0;
728
729 cp = fdt_getprop(blob, node, "compatible", &cplen);
730 if (cp == NULL)
731 return 0;
732 while (cplen > 0) {
733 score++;
734 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
735 return score;
736 l = strlen(cp) + 1;
737 cp += l;
738 cplen -= l;
739 }
740
741 return 0;
742}
743
744/**
745 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
746 * @node: node to test
747 * @compat: compatible string to compare with compatible list.
748 */
749int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
750{
751 return of_fdt_is_compatible(initial_boot_params, node, compat);
752}
753
754/**
755 * of_flat_dt_match - Return true if node matches a list of compatible values
756 */
757static int __init of_flat_dt_match(unsigned long node, const char *const *compat)
758{
759 unsigned int tmp, score = 0;
760
761 if (!compat)
762 return 0;
763
764 while (*compat) {
765 tmp = of_fdt_is_compatible(initial_boot_params, node, *compat);
766 if (tmp && (score == 0 || (tmp < score)))
767 score = tmp;
768 compat++;
769 }
770
771 return score;
772}
773
774/**
775 * of_get_flat_dt_prop - Given a node in the flat blob, return the phandle
776 */
777uint32_t __init of_get_flat_dt_phandle(unsigned long node)
778{
779 return fdt_get_phandle(initial_boot_params, node);
780}
781
782struct fdt_scan_status {
783 const char *name;
784 int namelen;
785 int depth;
786 int found;
787 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
788 void *data;
789};
790
791const char * __init of_flat_dt_get_machine_name(void)
792{
793 const char *name;
794 unsigned long dt_root = of_get_flat_dt_root();
795
796 name = of_get_flat_dt_prop(dt_root, "model", NULL);
797 if (!name)
798 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
799 return name;
800}
801
802/**
803 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
804 *
805 * @default_match: A machine specific ptr to return in case of no match.
806 * @get_next_compat: callback function to return next compatible match table.
807 *
808 * Iterate through machine match tables to find the best match for the machine
809 * compatible string in the FDT.
810 */
811const void * __init of_flat_dt_match_machine(const void *default_match,
812 const void * (*get_next_compat)(const char * const**))
813{
814 const void *data = NULL;
815 const void *best_data = default_match;
816 const char *const *compat;
817 unsigned long dt_root;
818 unsigned int best_score = ~1, score = 0;
819
820 dt_root = of_get_flat_dt_root();
821 while ((data = get_next_compat(&compat))) {
822 score = of_flat_dt_match(dt_root, compat);
823 if (score > 0 && score < best_score) {
824 best_data = data;
825 best_score = score;
826 }
827 }
828 if (!best_data) {
829 const char *prop;
830 int size;
831
832 pr_err("\n unrecognized device tree list:\n[ ");
833
834 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
835 if (prop) {
836 while (size > 0) {
837 printk("'%s' ", prop);
838 size -= strlen(prop) + 1;
839 prop += strlen(prop) + 1;
840 }
841 }
842 printk("]\n\n");
843 return NULL;
844 }
845
846 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
847
848 return best_data;
849}
850
851#ifdef CONFIG_BLK_DEV_INITRD
852static void __early_init_dt_declare_initrd(unsigned long start,
853 unsigned long end)
854{
855 /* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is
856 * enabled since __va() is called too early. ARM64 does make use
857 * of phys_initrd_start/phys_initrd_size so we can skip this
858 * conversion.
859 */
860 if (!IS_ENABLED(CONFIG_ARM64)) {
861 initrd_start = (unsigned long)__va(start);
862 initrd_end = (unsigned long)__va(end);
863 initrd_below_start_ok = 1;
864 }
865}
866
867/**
868 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
869 * @node: reference to node containing initrd location ('chosen')
870 */
871static void __init early_init_dt_check_for_initrd(unsigned long node)
872{
873 u64 start, end;
874 int len;
875 const __be32 *prop;
876
877 pr_debug("Looking for initrd properties... ");
878
879 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
880 if (!prop)
881 return;
882 start = of_read_number(prop, len/4);
883
884 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
885 if (!prop)
886 return;
887 end = of_read_number(prop, len/4);
888
889 __early_init_dt_declare_initrd(start, end);
890 phys_initrd_start = start;
891 phys_initrd_size = end - start;
892
893 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n",
894 (unsigned long long)start, (unsigned long long)end);
895}
896#else
897static inline void early_init_dt_check_for_initrd(unsigned long node)
898{
899}
900#endif /* CONFIG_BLK_DEV_INITRD */
901
902#ifdef CONFIG_SERIAL_EARLYCON
903
904int __init early_init_dt_scan_chosen_stdout(void)
905{
906 int offset;
907 const char *p, *q, *options = NULL;
908 int l;
909 const struct earlycon_id **p_match;
910 const void *fdt = initial_boot_params;
911
912 offset = fdt_path_offset(fdt, "/chosen");
913 if (offset < 0)
914 offset = fdt_path_offset(fdt, "/chosen@0");
915 if (offset < 0)
916 return -ENOENT;
917
918 p = fdt_getprop(fdt, offset, "stdout-path", &l);
919 if (!p)
920 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
921 if (!p || !l)
922 return -ENOENT;
923
924 q = strchrnul(p, ':');
925 if (*q != '\0')
926 options = q + 1;
927 l = q - p;
928
929 /* Get the node specified by stdout-path */
930 offset = fdt_path_offset_namelen(fdt, p, l);
931 if (offset < 0) {
932 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
933 return 0;
934 }
935
936 for (p_match = __earlycon_table; p_match < __earlycon_table_end;
937 p_match++) {
938 const struct earlycon_id *match = *p_match;
939
940 if (!match->compatible[0])
941 continue;
942
943 if (fdt_node_check_compatible(fdt, offset, match->compatible))
944 continue;
945
946 if (of_setup_earlycon(match, offset, options) == 0)
947 return 0;
948 }
949 return -ENODEV;
950}
951#endif
952
953/**
954 * early_init_dt_scan_root - fetch the top level address and size cells
955 */
956int __init early_init_dt_scan_root(unsigned long node, const char *uname,
957 int depth, void *data)
958{
959 const __be32 *prop;
960
961 if (depth != 0)
962 return 0;
963
964 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
965 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
966
967 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
968 if (prop)
969 dt_root_size_cells = be32_to_cpup(prop);
970 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
971
972 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
973 if (prop)
974 dt_root_addr_cells = be32_to_cpup(prop);
975 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
976
977 /* break now */
978 return 1;
979}
980
981u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
982{
983 const __be32 *p = *cellp;
984
985 *cellp = p + s;
986 return of_read_number(p, s);
987}
988
989/**
990 * early_init_dt_scan_memory - Look for and parse memory nodes
991 */
992int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
993 int depth, void *data)
994{
995 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
996 const __be32 *reg, *endp;
997 int l;
998 bool hotpluggable;
999
1000 /* We are scanning "memory" nodes only */
1001 if (type == NULL || strcmp(type, "memory") != 0)
1002 return 0;
1003
1004 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1005 if (reg == NULL)
1006 reg = of_get_flat_dt_prop(node, "reg", &l);
1007 if (reg == NULL)
1008 return 0;
1009
1010 endp = reg + (l / sizeof(__be32));
1011 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1012
1013 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
1014
1015 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1016 u64 base, size;
1017
1018 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1019 size = dt_mem_next_cell(dt_root_size_cells, ®);
1020
1021 if (size == 0)
1022 continue;
1023 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
1024 (unsigned long long)size);
1025
1026 early_init_dt_add_memory_arch(base, size);
1027
1028 if (!hotpluggable)
1029 continue;
1030
1031 if (early_init_dt_mark_hotplug_memory_arch(base, size))
1032 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1033 base, base + size);
1034 }
1035
1036 return 0;
1037}
1038
1039int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
1040 int depth, void *data)
1041{
1042 int l;
1043 const char *p;
1044 const void *rng_seed;
1045
1046 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
1047
1048 if (depth != 1 || !data ||
1049 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
1050 return 0;
1051
1052 early_init_dt_check_for_initrd(node);
1053
1054 /* Retrieve command line */
1055 p = of_get_flat_dt_prop(node, "bootargs", &l);
1056 if (p != NULL && l > 0)
1057 strlcpy(data, p, min(l, COMMAND_LINE_SIZE));
1058
1059 /*
1060 * CONFIG_CMDLINE is meant to be a default in case nothing else
1061 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1062 * is set in which case we override whatever was found earlier.
1063 */
1064#ifdef CONFIG_CMDLINE
1065#if defined(CONFIG_CMDLINE_EXTEND)
1066 strlcat(data, " ", COMMAND_LINE_SIZE);
1067 strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1068#elif defined(CONFIG_CMDLINE_FORCE)
1069 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1070#else
1071 /* No arguments from boot loader, use kernel's cmdl*/
1072 if (!((char *)data)[0])
1073 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1074#endif
1075#endif /* CONFIG_CMDLINE */
1076
1077 pr_debug("Command line is: %s\n", (char *)data);
1078
1079 rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
1080 if (rng_seed && l > 0) {
1081 add_bootloader_randomness(rng_seed, l);
1082
1083 /* try to clear seed so it won't be found. */
1084 fdt_nop_property(initial_boot_params, node, "rng-seed");
1085
1086 /* update CRC check value */
1087 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1088 fdt_totalsize(initial_boot_params));
1089 }
1090
1091 /* break now */
1092 return 1;
1093}
1094
1095#ifndef MIN_MEMBLOCK_ADDR
1096#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1097#endif
1098#ifndef MAX_MEMBLOCK_ADDR
1099#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1100#endif
1101
1102void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1103{
1104 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1105
1106 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1107 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1108 base, base + size);
1109 return;
1110 }
1111
1112 if (!PAGE_ALIGNED(base)) {
1113 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1114 base = PAGE_ALIGN(base);
1115 }
1116 size &= PAGE_MASK;
1117
1118 if (base > MAX_MEMBLOCK_ADDR) {
1119 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1120 base, base + size);
1121 return;
1122 }
1123
1124 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1125 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1126 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1127 size = MAX_MEMBLOCK_ADDR - base + 1;
1128 }
1129
1130 if (base + size < phys_offset) {
1131 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1132 base, base + size);
1133 return;
1134 }
1135 if (base < phys_offset) {
1136 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1137 base, phys_offset);
1138 size -= phys_offset - base;
1139 base = phys_offset;
1140 }
1141 memblock_add(base, size);
1142}
1143
1144int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1145{
1146 return memblock_mark_hotplug(base, size);
1147}
1148
1149int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1150 phys_addr_t size, bool nomap)
1151{
1152 if (nomap)
1153 return memblock_remove(base, size);
1154 return memblock_reserve(base, size);
1155}
1156
1157static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1158{
1159 void *ptr = memblock_alloc(size, align);
1160
1161 if (!ptr)
1162 panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
1163 __func__, size, align);
1164
1165 return ptr;
1166}
1167
1168bool __init early_init_dt_verify(void *params)
1169{
1170 if (!params)
1171 return false;
1172
1173 /* check device tree validity */
1174 if (fdt_check_header(params))
1175 return false;
1176
1177 /* Setup flat device-tree pointer */
1178 initial_boot_params = params;
1179 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1180 fdt_totalsize(initial_boot_params));
1181 return true;
1182}
1183
1184
1185void __init early_init_dt_scan_nodes(void)
1186{
1187 int rc = 0;
1188
1189 /* Retrieve various information from the /chosen node */
1190 rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1191 if (!rc)
1192 pr_warn("No chosen node found, continuing without\n");
1193
1194 /* Initialize {size,address}-cells info */
1195 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1196
1197 /* Setup memory, calling early_init_dt_add_memory_arch */
1198 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1199}
1200
1201bool __init early_init_dt_scan(void *params)
1202{
1203 bool status;
1204
1205 status = early_init_dt_verify(params);
1206 if (!status)
1207 return false;
1208
1209 early_init_dt_scan_nodes();
1210 return true;
1211}
1212
1213/**
1214 * unflatten_device_tree - create tree of device_nodes from flat blob
1215 *
1216 * unflattens the device-tree passed by the firmware, creating the
1217 * tree of struct device_node. It also fills the "name" and "type"
1218 * pointers of the nodes so the normal device-tree walking functions
1219 * can be used.
1220 */
1221void __init unflatten_device_tree(void)
1222{
1223 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1224 early_init_dt_alloc_memory_arch, false);
1225
1226 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1227 of_alias_scan(early_init_dt_alloc_memory_arch);
1228
1229 unittest_unflatten_overlay_base();
1230}
1231
1232/**
1233 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1234 *
1235 * Copies and unflattens the device-tree passed by the firmware, creating the
1236 * tree of struct device_node. It also fills the "name" and "type"
1237 * pointers of the nodes so the normal device-tree walking functions
1238 * can be used. This should only be used when the FDT memory has not been
1239 * reserved such is the case when the FDT is built-in to the kernel init
1240 * section. If the FDT memory is reserved already then unflatten_device_tree
1241 * should be used instead.
1242 */
1243void __init unflatten_and_copy_device_tree(void)
1244{
1245 int size;
1246 void *dt;
1247
1248 if (!initial_boot_params) {
1249 pr_warn("No valid device tree found, continuing without\n");
1250 return;
1251 }
1252
1253 size = fdt_totalsize(initial_boot_params);
1254 dt = early_init_dt_alloc_memory_arch(size,
1255 roundup_pow_of_two(FDT_V17_SIZE));
1256
1257 if (dt) {
1258 memcpy(dt, initial_boot_params, size);
1259 initial_boot_params = dt;
1260 }
1261 unflatten_device_tree();
1262}
1263
1264#ifdef CONFIG_SYSFS
1265static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1266 struct bin_attribute *bin_attr,
1267 char *buf, loff_t off, size_t count)
1268{
1269 memcpy(buf, initial_boot_params + off, count);
1270 return count;
1271}
1272
1273static int __init of_fdt_raw_init(void)
1274{
1275 static struct bin_attribute of_fdt_raw_attr =
1276 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1277
1278 if (!initial_boot_params)
1279 return 0;
1280
1281 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1282 fdt_totalsize(initial_boot_params))) {
1283 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1284 return 0;
1285 }
1286 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1287 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1288}
1289late_initcall(of_fdt_raw_init);
1290#endif
1291
1292#endif /* CONFIG_OF_EARLY_FLATTREE */